TITA or ‘Type in the Answer’ questions were introduced in CAT 2015 for the first time. They are the non MCQ questions where a student has to key in the answer using a virtual keypad. In CAT 2015, there were 32 questions; CAT 2016 had 25; followed by CAT 2017 having 20 questions of this type spread equally in all the three sections. The students are not penalized if they answer them wrongly but every correct answer fetches 3 marks.
Since CAT 2015, students have always faced problems with how to tackle the TITA questions, especially whether to attempt or to leave them. Many experts have more than once suggested that the aspirants should attempt all the TITA questions and in fact, students should not leave any one not attempted.
Among all the reasons behind attempting TITA questions in CAT, these are the most common ones stated by the students.
- There are no negative marks
Negative marks cannot be the sole reason for attempting or not attempting a question. It should rather depend on the students’ preparation, knowledge, confidence and strategy. Many students forget that TITA questions can be a trap also.
- TITA questions will be simpler
As there are no answer choices to these questions, students have a feeling that the TITA questions will be relatively easier than the MCQs. ‘Easy’ or ‘difficult’ is completely relative when it comes to problem solving, as it purely depends on the basic understanding of the subject area by the student. On a good day, the same question can look easy and doable than on any other day.
- I can guess the answer
Guessing an answer in the Quant section is nearly impossible if you have not solved the question correctly. Even for an intelligent guess, a student will have to reach as close as possible to the correct answer, which is also doubtful as they do not have the options to verify. The same is true for the DILR questions, as anybody not completely cracking the logic of the set will not be able to do any kind of guesswork. The TITA questions in the Verbal section had been comparatively easy to answer as compared to the Quants and DILR, as the questions were related to Parajumbles or identifying the odd sentence, where students were easily convinced about their choice of answer.
Also, managing time is one major problem in any competitive exam, and CAT is no different. TITA questions usually take more time to solve than many MCQ based questions as students cannot take the help of options to solve them. Students fail to keep track of time invested and end up losing a lot of time in the process, which can eventually get them a not so good score. So, a student should try to attempt the MCQ questions first and then move on to the non MCQ questions, especially in Quant and DILR.
Overall, the TITA questions test the basic understanding of the subject area and can be time consuming in many cases. Students should really be cautious and should always keep track on the time invested in those questions. As far as the guesswork is concerned, anybody can guess how good our guesses are!
All the best!
For more about him, you can click here.


In the immediate aftermath of the Holocaust, the world was faced with the challenge of attempting to seek justice for an almost unimaginable scale of criminal behavior—millions of murders, wrongful imprisonments, tortures; rape, theft, and destruction—perpetrated by the Nazis and their collaborators. The International Military Tribunal (IMT) held at Nuremberg, Germany, from November 20, 1945, until the verdicts were delivered on October 1, 1946, attempted to broach this immense challenge on a legal basis.
On view in this display are extended excerpts from the filming of the tribunal proceedings and artifacts connected to the courtroom. Interactive stations allow visitors to examine the IMT’s criminal charges, prosecution, defendants, evidence, and legacy through historic photos, documents, and eyewitness and defendant testimonies. The tribunal at Nuremberg set precedents in international law, in documentation of the historical record, and particularly in seeking some beginning, however inadequate, in a search for justice.
Wexner Center/From Memory to Action, Second Floor. No passes required.
War Crimes Trials (Holocaust Encyclopedia article)
Justice and Accountability (Center for the Prevention of Genocide)
Justice and Accountability in the Face of Genocide: What Have We Learned? (2011 Days of Remembrance Resource)
The Museum’s exhibitions are supported in part by the Lester Robbins and Sheila Johnson Robbins Traveling and Special Exhibition Fund established in 1990.


Definitions for Joppaˈdʒɒp ə
This page provides all possible meanings and translations of the word Joppa
Jaffa, Joppa, Yafo(noun)
a port in western Israel on the Mediterranean; incorporated into Tel Aviv in 1950
Joppa, Maryland in Harford County, Maryland is now a planning region for the county, but there was originally a town at the center called Joppa. Joppa was founded as a British colonial settlement in the early 18th century, and takes its name from the biblical town of Joppa. The town of Joppa on the Gunpowder River traded internationally in agricultural products, especially tobacco. At its peak, the port was home to about 50 homes, a church, prison, inns, shops, schools, armament factories, and warehouses. However, with the rise of Baltimore and Annapolis, Joppa declined as a port, and was slowly abandoned. By 1815, all that remained were ruins, and the surviving Rumsey Mansion. In 1962, Joppatowne, one of the first of a new generation of planned unit developments in the United States, was launched by the Panitz Company. McComas Institute was listed on the National Register of Historic Places in 1980. Olney was listed in 1987 and Whitaker's Mill Historic District in 1990.
The Nuttall Encyclopedia
an ancient town and seaport, now Jaffa, on the coast of Palestine, 35 m. NW. from Jerusalem; a place of note in sacred and mediæval history; here Jonah took ship to Tarshish.
The numerical value of Joppa in Chaldean Numerology is: 7
The numerical value of Joppa in Pythagorean Numerology is: 4
Images & Illustrations of Joppa
Translations for Joppa
From our Multilingual Translation Dictionary
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Implicitly opposing to miscegenation, cooper prefers to kill uncas, cora and magua in order to prevent an unsuitable marriage indeed, in his essay on the inequality of edit my paper online human races, joseph arthur de mobile marketing business plan gobineau asserted that whites were superior to other races and advised great special assignments nations to preserve their racial purity, since racial mixture, he claimed, led to corporate finance assignment cultural degeneration and political decline. the great gatsby essay topics december 20, how to start a persuasive essay introduction 2016. essay on interracial marriage, state laws, and halfway house business plan racial purity. dec 12, 2003 · when faulkner wrote the first of these searching narrative inquiries into how to start business plan homework excuse form the mystique of racial purity, the nuremberg laws racial purity essay of the nazi era were on the distant horizon and all research papers on psychology three appeared long before the apartheid system in south africa (modeled in part on our own jim crow laws) showed, for all the world to see, essay on life the untenable drift of racial discrimination may 28, 2008 · the concept of race has historically signified the division of humanity into a small number of groups based upon five criteria: love conquered virginia racial purity essay environmental pollution assignment the virginia anti-miscegenation law racial integrity act of 1924 was a law that enforced racial segregation of marriage between races. relevance. hutton specifically aims to show how racial anthropology contributed to race theory in germany, and what the effects were, both self introduction written sample for germany and racial anthropology racial purity essay itself apr 11, 2017 · consider, for example, an essay published in 1926 by hiram evans, the imperial wizard of the ku klux klan, in the exceedingly mainstream north …. the beautiful necessity – seven essays on theosophy and architecture by claude fayette bragdon. if you’d like to send your comments, please contact the instructor, jan haswell: international migration has reached racial purity essay record highs, as has the number of interracial marriages, leading to a surge of multiracial people such as shewmake. the author narrates the stories of two women (carrie buck and emma) creative writing prompts for children wallowing racial purity essay in poverty yet racial purity essay subjected to a purity racial scientific quest. the social contradictions are overwhelming, as racial identity becomes a figurative inheritance (rohrbach 486) people are different, but how society deals with these differences is what defines prejudice quest homework service and discrimination. dr.


Termites’ nests embody self-assembly of a different kind. Their nest is a giant ecosystem, complete with fungal farms and a sophisticated temperature control system , built by termites employing local cues from pheromones to orchestrate their behaviour.
Now a team at Harvard’s Wyss Institute, a biomimetic powerhouse, has created robots which can build a variety of large structures using algorithmic local cues after the manner of the termites. The bi g difference is that the robots can be programmed to execute a planned structure, rather as DNA can be programmed to create detailed structures on the basis of a computer coded algorithm defining its sticky end connections. The same planned structure will be built in a different order because once the robots start there is uncertainty about which particle robot will encounter which already built part of environment at any given time. The result though is always the same, just as it doesn’t matter in which order you complete a jigsaw.
The termites, of course have no master plan: the only rule governing the final form is that it has been selected by natural selection.
Science, 14 February 2014, pp. 754-758.


A new method of producing large volumes of high-quality graphene
May 2, 2014
The researchers say the discovery will “change the way many consumer and industrial products are manufactured.” Potential applications they cite include advanced food packaging, high-strength plastics, super-protective coatings for wind turbines and ships, and batteries with dramatically higher capacity than anything available today.
The graphene material can be further processed to create graphene oxide, used in electronics and other applications.
According to the research team, until now, researchers have been unable to produce graphene of high quality in large enough quantities; the research undertaken by AMBER is the first to perfect large-scale production of pristine (unoxidized and free of basal-plane defects) graphene materials.
Jonathan Coleman, Professor of Chemical Physics at Trinity College, and his team developed a simple method for transforming flakes of graphite into defect-free graphene using commercially available tools, such as high-shear mixers. They demonstrated that graphene-containing liquids can be produced at standard lab-scale quantities of a few hundred milliliters and they say the process could be scaled up to produce hundreds of liters or more.
Thomas Swan Ltd. has worked with the AMBER research team for two years and has signed a license agreement to scale up production and make the high-quality graphene available to industry globally. The company has announced two new products as a result of the research discovery: Elicarb Graphene Powder and Elicarb Graphene Dispersion.
The new research is described in Nature Materials. Thomas Swan Ltd. has invested €750,000 in the research program and plans a further collaboration with AMBER over the next 12 months, with joint funding by Science Foundation Ireland.
Abstract of Nature Materials paper
To progress from the laboratory to commercial applications, it will be necessary to develop industrially scalable methods to produce large quantities of defect-free graphene. Here we show that high-shear mixing of graphite in suitable stabilizing liquids results in large-scale exfoliation to give dispersions of graphene nanosheets. X-ray photoelectron spectroscopy and Raman spectroscopy show the exfoliated flakes to be unoxidized and free of basal-plane defects. We have developed a simple model that shows exfoliation to occur once the local shear rate exceeds 104 s−1. By fully characterizing the scaling behaviour of the graphene production rate, we show that exfoliation can be achieved in liquid volumes from hundreds of millilitres up to hundreds of litres and beyond. The graphene produced by this method performs well in applications from composites to conductive coatings. This method can be applied to exfoliate BN, MoS2 and a range of other layered crystals.


Asbestos Water Treatment
Why Do You Need to be Concerned About Asbestos?
Asbestos is a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Because of its fiber strength and heat resistant properties, asbestos has been used for a wide range of manufactured goods, mostly in building materials (roofing shingles, ceiling and floor tiles, paper products, and asbestos cement products), friction products (automobile clutch, brake, and transmission parts), heat-resistant fabrics, packaging, gaskets, and coatings.
When asbestos-containing materials are damaged or disturbed by repair, remodeling or demolition activities, microscopic fibers become airborne and can be inhaled into the lungs, where they can cause significant health problems. See more information on asbestos below.
Most Common Sources of Asbestos Exposure:
o Workplace exposure to people that work in industries that mine, make or use asbestos products and those living near these industries, including:
- the construction industry (particularly building demolition and renovation activities),
- the manufacture of asbestos products (such as textiles, friction products, insulation, and other building materials), and
- during automotive brake and clutch repair work
o Deteriorating, damaged, or disturbed asbestos-containing products such as insulation, fireproofing, acoustical materials, and floor tiles.


What are transferable skills and why do you need them? What does it mean to be employable today and in the future?...
- One of the most exciting and challenging jobs, with the opportunity to travel into space
- Requires excellent scientific or flight skills as well as physical and psychological strength
- A flight in space could last between 6 months and a year
As an astronaut, you'll be trained to fly and maintain spacecraft so you can live safely onboard, and you might also carry out scientific experiments and research. You may also do Extra Vehicular Activity (EVA) or spacewalks to repair the spacecraft or complete research experiments.
Astronauts need to be able to apply their considerable knowledge and skills to the tasks for which they have been trained; be able to bear tremendous responsibility while in orbit; and be determined to succeed.
On the ground you'll be involved in extensive training and preparations for your space flight. Once you're selected, you'll get mission-specific training. Your flight in space could last between 6 months and a year.
Once you are in space your daily activities might include:
- Cleaning and testing air filters and air quality
- Repairing, maintaining and testing oxygen production systems
- Cleaning and maintaining water systems and testing for bacterial growth
- Packaging and disposing of waste
- Replacing worn or broken parts on the spacecraft
- Installing or repairing scientific instruments and equipment
- Setting up, carrying out and monitoring experiments
- Taking samples like blood from astronauts to assess their health
- Communicating with Earth by satellite to transfer data and send reports
You'll need a high level of physical fitness to help you cope with life in space, because of the cramped living conditions and the effects of low gravity on your body. You'll need to spend around 2.5 hours a day exercising when in space to maintain your physical health and stamina.
You'll need excellent leadership skills, strong physical coordination, scientific knowledge, and the ability to stay calm and make quick decisions under pressure. You'll also be away from home for extended periods of time and you'll usually need to travel overseas for training. You'll have several years' training before you're ready to be selected for a mission.
Opportunities to become an astronaut are very limited and competition for places is very strong. Most people progress onto becoming an astronaut after a career as a pilot or as a scientist. As a pilot, you'll need at least 1,000 hours of flying experience in a high performance aircraft like a fighter jet. As a scientist you'll normally need to have a PhD in a subject like biology, chemistry, engineering, information technology, mathematics, or physics.
You will need to able to speak English fluently and it would also help if you could speak a second language, like Russian, which is used on the international space station.
With either of these routes, you'll usually need at least 3 years experience, and will usually need to be between 27 and 37 years old. With aircraft pilot experience or scientific experience you could apply to become an astronaut in the European Astronaut Corps. To become an astronaut with NASA, you'll need to have US citizenship or US dual-citizenship.
You'll have several years' training before you're ready for a mission. It may take you years to be selected for a space flight. Once you're selected, you'll get mission specific training. Your flight in space could last between 6 months and a year.
With experience you could:
- be selected for other missions
- move into management, teaching or research
- set up your own consultancy business
You can find out more about related career opportunities in space exploration from the European Space Agency.


Improving Health Through Better Water Filtration
No one will argue the fact that everyone needs a steady supply of safe water to continue living. The arguments usually start when health experts disagree on what constitutes safe water. It’s been well established that much of the Earth’s water supply is contaminated with a wide variety of chemicals. Much of the world’s water supply contains high levels of minerals that make it less than healthy for consumers.
How Do Consumers Know If Their Water Is Safe?
Most tap water from municipal sources is tested to ensure contaminants are within “safe” limits, but who determines what those safe levels are, and should users blindly accept their findings?
Governmental agencies are generally responsible for determining what those acceptable levels are, but water safety is about more than defining an “acceptable” level of contamination. Consumers need to be asking themselves whether or not high levels of minerals or the presence of any pharmaceuticals is genuinely safe.
TRICK: You can clean up water marks from glass vases. Or fill the vase with water and drop in 2 Alka Seltzer tablets.
Can Consumers Take Steps to Improve the Quality of Their Drinking Water?
The short answer is yes, and there are several options to consider when consumers seek a way to improve the quality of the water they drink. A variety of filtering systems are currently marketed to enhance water quality. The problem is that many don’t really resolve all the issues involved.
Why Are PH Levels Important?
Here’s where there seems to be a great deal of important information available. In an article at http://www.precisionnutrition.com/, Ryan Andrews explains that a pH level of about 7.0 is typical for most tap water, which is regarded as being neutral. He discusses the fact that a human body will seek a balance near that neutral point and that a pH level that is out of balance in either direction will create issues.
Nutrition experts universally espouse the importance of safe water. Within recent years many water studies, like The Alkaline Diet: Is There Evidence That an Alkaline pH Diet Benefits Health?, by Gerry K. Schwalfenberg, suggest there are benefits of ingesting more alkaline substances in a diet to improve health. In fact, newer water filtering devices are currently being used to increase alkalinity and help users avoid chronic low-grade acidosis, which some researchers believe causes health issues.
Andrews, in his article, argues that pH levels impact overall health, and obtaining a balance is essential, but “Without knowing the cause, you can’t determine whether alkaline water will really help you.”
While that statement has value and should not be ignored, especially if chronic medical issues are present, the importance of drinking only quality water should always take priority.
How Can Users Ensure They Always Have Quality Drinking Water?
First of all, it’s essential to recognize the fact few water sources are actually delivering water that’s as pure as it should be. That means users have to take matters into their own hands and look at the options out there to improve the quality of the water they drink.
One of the current trends in water filtration involves the use of filters, including tourmaline.
“Took the SureAqua pump on a Scout Hike with 15 boys and girls. It was so good not to carry so much water. The scouts are only allowed to carry 20% of their body weight. Not much! It was great, so the kids were able to carry food and tents rather than lbs of water.”
Did you know nearly 79% of your body mass is Water!
Why Is Tourmaline Used?
The Global Healing Center in “Benefits of Tourmaline Gemstone” states that tourmaline “is known to aid in relieving stress, increasing mental alertness, improving circulation, and strengthening the immune system.” While the article did not precisely explain how that happens, it hints that the electrical charge influences those outcomes.
In addition, the article states tourmaline “produces a detoxifying, cleansing effect on the nervous system, as well the organs and tissues of the body.” Those benefits are frequently a topic of argument, but anecdotal evidence has been around for centuries, suggesting that the mineral enhances health. That’s why it’s now being incorporated into water filtering systems, even though more research needs to be undertaken to determine how much of an effect the tourmaline has.
In modern filters, tourmaline is used to increase alkalinity during the filtering process to deliver pure water to improve the user’s pH levels. The best systems use several stages of filtration to remove chemicals, bacteria, and viruses that frequently threaten those who are drinking unfiltered water.
“Never again will I leave my portable water filter behind after I spent a straight 5 hours in a toilet in India.”
Are Filters Available for Users on the Go?
Certainly, filters are available in different styles and sizes to accommodate travelers, campers, hikers, and anyone else venturing out into areas where water quality is questionable. While the water in a given location may be safe to drink, it’s always better to avoid the potential of coming down with a water-related illness. Carrying a portable filter using tourmaline as a component is always a good idea for anyone wanting a safe, reliable water supply.
Of course, there are also other reasons to consider portable filtering devices. Bottled water is readily available in many areas. Still, bottled water quality has come under question in recent years as many bottlers openly admit using municipal supplies as their water sources. While they may filter the water further, users have no way to determine the purity of bottled water.
Final Say about water filter benefits
In addition, bottled water produces massive amounts of plastic waste. Using a portable water filtering system eliminates that waste and allows users to know the level of filtration their water is receiving. Since the better filtering products currently available are thoroughly tested and last for years, users can be assured their water will have a pleasant taste and be healthier than the water typical municipal systems deliver.
Whether a user is traveling or simply wants a reliable method of filtering the water they drink every day, exploring the filtering options readily available, especially those including tourmaline in the process, is essential. Clean, safe water not only tastes better, but it is also healthier for users. Prices are also important, but some of the best options are reasonably priced, making them readily available to virtually anyone.


“Accountability” is a big word with a big meaning. Accountability means taking responsibility. Our national and state education laws now hold every public school responsible for the academic performance of every one of its students —regardless of the student’s race or ethnicity, whether the student is rich, poor, disabled, or learning English as a new language.
The Massachusetts School and District Accountability System holds schools accountable for educating all students to high standards and for making sure all children are learning. This system requires all public schools, including charter schools, to communicate to their students, their parents, and to the whole community where they are succeeding and where there is still work to do.
The system also holds students accountable for doing their best. In order to earn their high school diploma, students must earn a Competency Determination that is based on their MCAS scores.
Accountability begins with a Goal
The national goal is that all students will be proficient or better in Math and Reading (also called English Language Arts) by the 2013-14 school year. “Proficient” means that the student is at grade level. The accountability system helps to make sure that all students are making enough progress to meet the goal.
Adequate Yearly Progress (AYP)
AYP is the measure of yearly progress toward all students achieving at or above grade level in English language arts and mathematics by the 2013-14 school year.
AYP determinations are based on four factors:
1. Participation – At least 95% of students must participate in MCAS tests
2. Performance or Improvement – Based on students’ scores on MCAS tests
3. Attendance (for elementary & middle schools) – at least 92% annual attendance rates or 1% improvement in attendance
4. Graduation rate for high schools – A graduation rate of at least 65% or show improvement
AYP is important because it measures progress of all groups of students. In the past, schools could appear to be providing a good education if the average scores were high. In reality, these averages often hid the fact that specific groups of students were not making academic progress. Today, if just one student group at a school does not meet an AYP goal, then the school does not make AYP for that year. In this way, schools are held accountable for making sure all groups of student make progress, even those who have been left behind in the past. Student groups include:
(1) All students in the school, and students who are
(3) African American
(5) Native American
(7) Economically disadvantaged
(8) English language learners
(9) Students with disabilities
School Report Cards
Simply testing students is not enough to hold schools accountable. Parents, students, and the general public have to be informed of the test results. Every year, school districts that receive Title I funds must prepare a Report Card for the individual public schools in that district. It must give details of the schools’ performance in each AYP element for the total school and for each student group. (For more on NCLB School Report Cards, please see our Pointers on that topic.)
For schools that receive federal Title I funding, the school’s AYP performance is also use to make special options available to students. To learn more about these options, please see our Bulletin on “Free Tutoring Available under the No Child Left Behind Act” and our Pointers on “Public School Choice Under NCLB.”
In addition to School Report Cards, parents receive a “Parent/Guardian Report” that gives details about their own child’s performance on MCAS assessments. To learn more about reports on individual students, please see our Bulletin “MCAS Parent/Guardian Report: A Roadmap.”
Failure to Make AYP
In addition to the special options mentioned above that Title I schools must make available to families if they do not meet their AYP goals, NCLB also lays out an action plan to help districts and schools that are not meeting AYP goals. First, the district identifies the kind of help a school needs. Districts provide technical assistance and help the school administrators develop and carry out a school improvement plan with parental input. The plan might include professional development for teachers, or possibly a new curriculum. The point is to help schools in their efforts to improve student achievement.
Mass Department of Elementary and Secondary Education Resources on NCLB and AYP
Information on No Child Left Behind For Parents and Guardians
• AYP Facts
NCLB Report Cards
School Choice Programs
Supplemental Educational Services
• School Leaders’ Guide to the 2009 Adequate Yearly Progress (AYP) Reports”


Every day, close to 3,600 children aged 19 and younger are treated for vehicle accident-related injuries in emergency rooms across the nation. To protect children in an auto accident, it's vital to learn ways to reduce this deadly serious risk.
Use Safety Restraints Correctly
Even with the plethora of restraint devices available, approximately 80 percent of children aren't properly secured when they ride in vehicles. Statistics clearly show that with proper and consistent use of child restraint seats, collision-related injuries and fatalities are preventable:
- Correct use of a car seat lowers the risk of death by 71 percent for infants and 54 percent for toddlers.
- Use of a booster seat reduces the risk of serious injuries in children aged 4 to 8 years in comparison to using only a seat belt.
Child Seat and Seat Belt Safety Tips
The following tips can help you safeguard the lives of your children and reduce the risk of life-threatening injuries every time they ride:
- Restrain children age 12 and under in the back seat even if your vehicle doesn't have front-seat air bags.
- Use a rear-facing car seat for an infant weighing less than 20 pounds.
- Never place a rear-facing car seat in the front seat, regardless of whether or not the vehicle is equipped with air bags.
- Read the manufacturer's instructions and vehicle owner's manual to make certain you install a car seat correctly.
- Place children over age 1 and weighing 20 to 40 pounds in a forward-facing car seat.
- Restrain children aged 4 to 8 who weigh 40 to 80 pounds in a booster seat.
- Children weighing over 80 pounds should be restrained with seat belts whenever the vehicle is moving.
- Regardless of age and weight, don't switch from using a booster seat to a seat belt until a child is taller than 57 inches.


Air Quality Assessment
ARPA Lazio, the regional environmental agency operates several air quality monitoring sites
in the Lazio Region, including Rome. The Rome monitoring network consists of 13 monitoring
stations classified as four different types: A,B,C and D. Type A are usually located in areas
not directly affected by traffic sources such as parks or green areas. They monitor pollutants
such as CO, SO2, NOx, NO, BTX, PM10 and O3. Type B are located in areas with heavy traffic
conditions. They monitor CO, NOx, BTX, PM10 and O3. Type C are located in residential areas.
They monitor CO, NOx and BTX. Type D are located outside the urban area, almost in the countryside.
They monitor O3 and NOx, and are devoted to the control of photochemical pollution.
The monitoring network acquires concentration data every hour. Data are sent to the Regional
Environmental Protection Agency (ARPA) for validation and delivered to the Environmental Department
of the Municipality of Rome that is responsible for data collecting, storing and delivering.
Moreover the Municipality of Rome carries out campaigns with diffusion tubes. These campaigns
last one week and are distributed across the whole urban area, during different periods of the year.
Monitoring tubes are usually located in secondary streets, to provide information on background
concentrations. They last one week and are distributed in different periods of the year. BTX, NO2
are measured plus O3 in summer time.
From the analysis of the current air situation, it is evident that traffic is mainly responsible
for the high pollutant concentrations. Traffic is the main source of CO, C6H6 and PM10 concentrations.
High concentrations are recorded next to heavy traffic areas, whilst background concentrations do not
exceed the limits. SO2 concentrations are below limits and quality objectives as industrial activity
has ceased to be a dominant source of air pollution.
In the Rome Metropolitan area air quality indicators for particulate matter and nitrogen dioxide are
sometimes beyond the limits set in the EU directives on air quality, while Benzene is generally not a problem.
In the pictures, the PM10 and NO2 situation in the monitoring sites is shown. Industrial emissions have
steadily decreased over recent decades and previous modelling exercises show that management of transport
related emissions may be a key factor in achieving compliance with the EU directives.


Health > Chilblains
Chilblans are a painful sore appearing on the foot or the hand which is caused by exposure to cold.
This condition may be associated with poor circulation.
The best treatment is to avoid getting cold and wet. Try hard not to scratch them.
Herbal Remedies - A herbal poultice which may be useful can be made from one part cayenne pepper, one part slippery elm powder and two parts vegetable oil, mixed together and applied morning and night.
A poultice of chickweed is also known to ease the pain of chilblains. Another good herb for chilblains is prickly ash - available as a tincture or in fluid extract.
Try a cup of ginger tea twice a day. Eat garlic or take garlic capsules.
Ginkgo may also be very helpful for this condition.
Aromatherapy - Try black pepper essential oil in a foot bath or diluted in a light base cream.
Eat more fish, fresh fruit and vegetables, fibre, filtered water and get plenty of gentle exercise.


Physicists may have detected something unbelievable from space - watch the announcement live this morning
Called gravitational waves, the ripples in the fabric of space are caused by colliding black holes, merging neutron stars, exploding stars, and other cataclysmic events.Two astronomers discovered the first evidence of gravitational waves back in 1974.
"It would revolutionize physics to detect them," Szabi Marka, a physicist at Columbia University, told Tech Insider. "Some say it's the last undiscovered territory of Einstein."Aside from proving fundamental physics, direct detection of gravitational waves would also open up a new era of astronomy. Researchers could detect exploding stars before any of their light reaches Earth, probe the secrets of black holes, and understand what happens when - and how often - dead stars violently collide.
"We could learn about something that was impossible to touch before," Marka said.Insiders believe the big news is that Laser Interferometer Gravitational-Wave Observatory (LIGO), a $1 billion experiment that has searched for signs of the phenomenon since 2002, has detected gravitational waves coming from two black holes colliding deep in space.Cliff Burgess, a physicist at McMaster University and the Perimeter Institute for Theoretical Physics, told Tech Insider that this and similar rumors "have only gotten more detailed since they first started going around last year" and hopes they're not a ruse.
Today we'll find out if those rumors are true - and you can too by watching the YouTube livestream video (below).
The National Science Foundation (NSF) is hosting the live feed along with scientists from LIGO.The feed should open up around 10:15 a.m. EST and officially begin at 10:30 a.m. EST on Thursday, February 11:
Note that the NSF and LIGO webcast is probably going to be a bit technical, but Tech Insider will have a lot of nerds watching to bring you the latest news in comprehensible form.You can stay tuned for updates at TechInsider.io, follow us on Twitter, or keep tabs on our Facebook page.
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Modelling shows that ocean currents can concentrate slow-degrading debris in certain parts of the world’s oceans, leading to so-called ‘garbage patches’
It is estimated that between four and 12m metric tonnes of plastic makes its way into the ocean each year. This figure is only likely to rise, and a 2016 report predicted that by 2050 the amount of plastic in the sea will outweigh the amount of fish.
A normal plastic bottle takes about 450 years to break down completely, so the components of a bottle dropped in the ocean today could still be polluting the waters for our great-great-great-great-great-great-great-great-great-great-great-great-great-great-great-great-grandchildren.
A lot of plastic debris in the ocean breaks down into smaller pieces and is ingested by marine life, and it is thought that a significant amount sinks to the sea bed. But a lot of it just floats around, and thanks to sophisticated modelling of ocean currents using drifting buoys, we can see where much of it ends up.
Oceanographer Erik van Sebille has shown that, thanks to strong ocean currents known as gyres, huge amounts of plastic end up in six “garbage patches” around the world, the largest one being in the north Pacific.
As can be seen in the image above, a bottle dropped in the water off the coast of China, near Shanghai, is likely be carried eastward by the north Pacific gyre and end up circulating a few hundred miles off the coast of the US.
A bottle dropped off the Mexican coast, near Acapulco, is likely to be caught in the same gyre. Some of the plastic waste drifts south, but a huge amount is swept west towards Asia before floating north and ending up in the same area – the so-called Great Pacific Garbage Patch.


By Jo Twist
BBC News website science and technology reporter
Online communities set up by the UK government could encourage public debate and build trust, says the Institute of Public Policy Research (IPPR).
Existing services such as eBay could provide a good blueprint for such services, says the think-tank.
Online auction site eBay has a 'reputation system'
Although the net is becoming part of local and central government, its potential has not yet been fully exploited to create an online "commons" for public debate.
In its report, Is Online Community A Policy Tool?, the IPPR also asks if ID cards could help create safer online communities.
Adopting an eBay-type model would let communities create their own markets for skills and services and help foster a sense of local identity and connection.
"What we are proposing is a civic commons," Will Davies, senior research fellow at the IPPR told the BBC News website.
"A single publicly funded and run online community in which citizens can have a single place to go where you can go to engage in diversity and in a way that might have a policy implication - like a pre-legislation discussion."
The idea of a "civic commons" was originally proposed by Stephen Coleman, professor of e-democracy at the Oxford Internet Institute.
The IPPR report points to informal, small scale examples of such commons that already exist.
It mentions good-practice public initiatives like the BBC's iCan project which connects people locally and nationally who want to take action around important issues.
But he adds, government could play a bigger role in setting up systems of trust for online communities too.
Proposals for ID cards, for instance, could also be widened to see if they could be used online.
They could provide the basis for a secure authentication system which could have value for peer-to-peer interaction online.
"At the moment they have been presented as a way for government to keep tabs on people and ensuring access to public services," said Mr Davies.
"But what has not been explored is how authentication technology may potentially play a role in decentralised online communities."
The key idea to take from systems such as eBay and other online communities is letting members rate each other's reputation by how they treat other members.
Using a similar mechanism, trust and cooperation between members of virtual and physical communities could be built.
This could mean a civic commons would work within a non-market system which lets people who may disagree with one another interact within publicly-recognised rules.
E-government initiatives over the last decade have very much been about putting basic information and service guides online as well as letting people interact with government via the web.
Many online communities, such as chatrooms, mailing lists, community portals, message boards and weblogs often form around common interests or issues.
With 53% of UK households now with access to the net, the government, suggests Mr Davies, could act as an intermediary or "middleman" to set up public online places of debate and exchange to encourage more "cosmopolitan politics" and public trust in policy.
eBay rewards sellers that have exceptional levels of success and positive feedback
"Government already plays a critical role in helping citizens trade with each other online.
"But it should also play a role in helping citizens connect to one another in civic, non-market interactions," said Mr Davies.
There is a role for public bodies like the BBC, libraries, and government to bring people back into public debate again instead of millions of "cliques" talking to each other, he added.
The paper is part of the IPPR's Digital Society initiative which is producing a number of conferences and research papers leading up to the publication of A Manifesto For A Digital Britain.


Back to Calculation Tips & Tricks
- even numbers 2 through selected 2-digit evens
- digits of square of repeating ones
- consecutive odds
- consecutive between 2 numbers
- sequence from 1 to selected 2-digit number
- sequence from 1 to selected 1-digit number and back
- sequences in the 10's
- sequences in the 20's
- sequences in the 30's
- sequences in the 40's
- sequences in the 50's
- sequences in the 60's
- sequences in the 70's
- sequences in the 80's
- series of doubles
- series of quadruples
- series of 10 numbers
- 1's repeating, divide by 9, subtract 21
- 8's repeating, divide by 9, subtract 10
- squares of two numbers
- reversing/adding/subtracting 3-digit numbers
- finding 2.5 percent
- finding 5 percent
- finding 15 percent
- finding 20 percent
- finding 25 percent
- finding 33 1/3 percent
- finding 40 percent
- finding 45 percent
- finding 55 percent
- finding 60 percent
- finding 70 percent
- finding 75 percent
a series of doubles
- Have a friend choose a a single digit number. (No restrictions for experts.)
- Ask your friend to jot down a series of doubles (where the next term is always
double the preceding one), and tell you the last term.
- Ask your friend to add up all these terms.
- You will give the answer before he or she can finish: The sum of all the terms
of this series will be two times the last term minus the first term.
- If the number selected is 9:
- The series jotted down is: 9, 18, 36, 72, 144.
- Two times the last term (144) minus the first (9):
2 × 144 = 288; 288 - 9 = 279.
- So the sum of the doubles from 9 through 144 is 279.
See the pattern? Here's one for the experts:
- The number selected is 32:
- The series jotted down is: 64, 128, 256, 512.
- Two times the last term (512) minus the first (64):
2 × 512 = 1024; 1024 - 32 = 1024 - 30 - 2 = 994 - 2 = 992.
- So the sum of the doubles from 32 through 512 is 992.
Remember to subtract in steps from left to right.
With practice you will be expert in summing series.
© 1994-2014 Drexel University. All rights reserved.
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Withdrawal is the response of the body to the discontinuance of an addictive substance. The symptoms can range from mild to severe and in extreme cases can be life threatening.
With all addictive substances, the body tolerates higher and higher doses and the therapeutic effect of the drug is lessened. However, the body's functions adjust themselves to the addition of the drug so that the addicted person may function more or less normally. However, once the addict ceases to use the drug, the body reacts adversely until it can once again adjust to the new situation, for example:
- It mistakes the lack of the drug for poisoning and rejects food, making the patient nauseous and inducing vomiting.
- It believes that the body temperature is too high and starts sweating to reduce it.
- Normal sleep cycles are disturbed, causing insomnia and fatigue.
All addictive substances cause withdrawal. The symptoms can be mild (caffeine withdrawal causes fatigue, nausea and headaches), to moderate (nicotine withdrawal causes anxiety) to severe (alcohol withdrawal, or the DTs, can cause hallucinations, anxiety, convulsions and death). Withdrawal can also result from the sudden cessation of therapeutic drugs such as tranquilizers or steroids.
Some drugs can be substituted for the addictive drugs, thus preventing the withdrawal symptoms. For example, methadone is a common substitute for heroin, and the nicotine patch contains the same drug as cigarettes without the side effects.


Innovative MABR Research Makes Lake and Stream Conservation More Effective
MABR scientists have developed a pioneering, comprehensive approach that makes conserving and managing freshwater lakes, streams and wetlands more integrated and effective.
“We call our approach landscape limnology,” explained Patricia Soranno, MABR fisheries and wildlife scientist. “It’s a new way to study fresh water that considers all fresh waters together—lakes, rivers and wetlands—as they interact with one another and with natural and human landscapes. Our goal is to improve our broad understanding of the diversity of freshwater resources and to give freshwater managers science-based tools to manage and protect these bodies of water.”
The research was published in the June 1 issue of the journal BioScience.
Michigan has more than 10,000 freshwater lakes larger than 5 acres, 30,000 miles of streams and more than 10,000 square miles of wetlands. State agencies—mainly the Department of Natural Resources and Environment (DNRE)—are charged with the enormous task of managing these freshwater resources to make sure all needs are met, including overseeing fish stocking and fishing regulations, applying herbicides to control aquatic plants, and setting withdrawal regulations and nutrient standards. But with limited budgets, data can be collected on only a small percentage of these aquatic resources.
Landscape limnology uses geographical information systems (GIS) data from satellites and aerial photos, including information on land use, soils and geology around the freshwater resources. This information is combined with data collected in the field, such as fish population numbers or nutrient levels in the water, to create models that decision makers can use to decide on the best management and conservation strategies to meet their goals.
Landscape limnology differs from traditional limnology by looking at freshwater resources as an integrated part of a complex landscape of terrestrial and aquatic elements rather than considering each lake or wetland as a single, isolated entity.
Soranno and MSU co-authors Mary Bremigan, MABR fisheries and wildlife scientist, and Kendra Spence Cheruvelil, assistant professor of fisheries and wildlife, said many current and emerging environmental issues have causes that range in scale from local to global. All three are members of the MSU Landscape Limnology Research Group. Land use change, exotic species invasions and climate change are all complex issues linked in ways that can be understood only by taking an approach that includes all these scales as well as freshwater, terrestrial and human landscape information. The Asian carp invasion, for example, may be linked to an increase in water temperature associated with climate change, the interconnectivity of inland lakes and streams, and the type of development happening along the shoreline.
“A landscape approach that considers what’s happening at both the local water-body scale and at the broader regional scale is really the only way to study these types of issues,” Cheruvelil said. “If you look at only one ecosystem in isolation, you don’t see the whole picture.”
“The landscape limnology framework makes it easy to run several complementary models at the same time,” Bremigan added. “Right now, the people who manage fish use one model, and the people who manage nutrient levels use a completely different model, and they’re rarely compatible, so it can be difficult to see how changes in one affect the other. Landscape limnology models make it easier to see the relationships among all the variables.”
The DNRE began using the MSU scientists’ landscape limnology approach in 2006 to set and manage nutrient levels in the state’s freshwater lakes and streams, and the managers are very pleased with the results.
“The state of Michigan had to present our approach to U.S. Environmental Protection Agency [EPA] officials, and they gave us a very favorable review,” Soranno said. “Now we’re starting to work with agencies outside Michigan.”
Other paper co-authors are Katherine Webster, of the School of Biological Sciences at Queen’s University in Belfast; Tyler Wagner, of the Pennsylvania Cooperative Fish and Wildlife Research Unit, U.S. Geological Survey, at Pennsylvania State University; and Craig Snow, of the Great Lakes Environmental Research Laboratory, National Oceanic and Atmospheric Association.
The research is supported by the EPA Office of Wetlands, Oceans and Watershed National Lakes Assessment Planning Project. The research of Soranno and Bremigan also is supported by Michigan AgBioResearch.
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Open Access This article is
- freely available
Aerospace 2018, 5(3), 81; doi:10.3390/aerospace5030081
Life Cycle Assessment of Ramie Fiber Used for FRPs
School of Civil Engineering, Harbin Institute of Technology (HIT), 73 Hanghe Road, Nangang District, Harbin 150090, China
Faculty of Science & Engineering, University of Nottingham Ningbo China (UNNC), Ningbo 315000, China
National Key Laboratory of Advanced Composites, AVIC Composite Technology Center, AVIC Composite Corporation Ltd. (ACC), Beijing 101300, China
Author to whom correspondence should be addressed.
Received: 15 June 2018 / Accepted: 31 July 2018 / Published: 3 August 2018
With the depletion of natural resources and the deterioration of environment, natural fiber based biomaterials are attracting more and more attentions. Natural fibers are considered to be renewable, biodegradable, and ecofriendly, and have been applied to be used as alternative reinforcements to traditional glass fibers for polymer based composites (GFRP). Natural fiber reinforced polymer (NFRP) composites have been found to be manufactured as secondary structures or interior parts of aircrafts or automobiles. In this paper, a cradle-to-gate life cycle assessment (LCA) study was performed to demonstrate the possible advantages of ramie fiber on environmental impacts and to provide fundamental data for the further assessment of ramie fiber reinforced polymers (RFRP) and its structures. By collecting the material inventories of the production process of ramie fiber, the environmental impacts of ramie fiber (characterized by eight main impact categories, which are climate change, terrestrial acidification, freshwater eutrophication, human toxicity potential, ozone depletion, photochemical oxidant creation, freshwater ecotoxicity, and fossil depletion) were calculated and compared with that of glass fiber. Found if spinning process is ignored within the production of the ramie fiber, ramie fiber exhibits better ozone depletion and they have almost the same values of climate change and terrestrial acidification in terms of glass fiber. However, if the spinning process is included, ramie fiber only performs better in terms of ozone depletion. And degumming and carding and spinning processes are the processes that cause more pollution.
Keywords:ramie fiber; life cycle assessment; glass fibre; environmental impacts
Fiber reinforced polymers (FRPs) have been widely used in modern industries because of their numerous advantages, like high specific strength and modulus, excellent fatigue performances, resistance to corrosion, and so on. The areas in which FRPs have been applied include aircraft, automotive, marine, sporting goods, infrastructure, and so on .
The fiber reinforcements used for FRPs are generally carbon- or glass-fibers. The production of such traditional fibers will bring in high emissions of greenhouse gases and the depletion of raw material natural resources (e.g., fossil fuel). Natural fibers are introduced and used in secondary or decorative structures considering their mechanical properties, because they are considered to be raw materials available, biodegradable, eco-friendly. Recently, natural fibers (e.g., ramie fiber, flax fiber, etc.) have been developed and utilized as a substitute for traditional glass fiber, to serve as fiber reinforcements of FRPs [2,3,4].
The life cycle assessment (LCA) of FRPs has received extensive attention for a better understanding of the environmental problems of FRPs and its structures. For example, regarding the traditional carbon FRPs (CFRPs) and glass FRPs (GFRPs), Foraboschi [5,6] studied the environmental problems of using FRP to strengthen masonry and reinforced concrete (RC) structures. For natural fiber reinforced polymers (NFRPS), there are many LCA studies on various natural fibers. Le Duigou et al. , and Summerscales and Dissanayake  have studied the environmental problems of flax fiber used in FRPs. Also, a comparative life cycle assessment (LCA) study was done between two bus body components made of hemp fiber reinforced polymers (HFRP) and GFRP . It was found that the hemp-based composites show a lower environmental impact. Furthermore, LCA studies of jute fiber and sisal fiber have also been found [9,10].
In this article, the LCA of another widely used natural fiber, ramie fiber, was studied, because it is one of the best fibers that has better mechanical properties  in natural fibers and it can be used in ramie fiber reinforced polymers (RFRP). To the best of our knowledge, research about the environmental problems of ramie fiber is still limited.
Ramie, known as Chinese grass, is a perennial herbaceous plant of the Urticaceae family and it is mainly cultivated in Asia . China contributes more than 90% of the cultivation of ramie in the world . In Chinese major production areas, ramie can be harvested three times in one year . As ramie fibers are abundant and can meet the requirements of FRP manufacturing, in the European Union’s Horizon 2020 research and innovation programme between China and European (Grant No., 690638), ramie fiber was selected to manufacture some of the secondary structures of airports.
In the present study, a cradle-to-gate LCA was performed for the ramie fiber in order to demonstrate the possible advantages of ramie fiber on the environmental impacts and to provide fundamental data for further the assessment of RFRP and its structures. The inventories of the processes, including ramie cultivation, harvesting, peeling, transportation, degumming, and carding and spinning, were collected and calculated. Then, eight environmental categories, namely, climate change, terrestrial acidification, freshwater eutrophication, human toxicity potential, ozone depletion, photochemical oxidant creation, freshwater ecotoxicity, and fossil depletion, were used to characterize the environmental impacts of the ramie fiber. Finally, the environmental impacts of the ramie fiber were compared with that of glass fiber, based on the same mass. A professional LCA software, GaBi, was used to perform the LCA study . The results show that if the spinning process is ignored within the production of the ramie fiber, the ramie fiber exhibits better ozone depletion and they have almost the same values on categories like climate change and terrestrial acidification, in terms of glass fibre. However, if the spinning process is included, the ramie fiber performs only better in term of the ozone depletion. The degumming, and carding and spinning processes are the processes that cause more pollution.
Quantitative LCA was the research methodology that was used in the present study to quantify the environmental performance of the ramie fiber. LCA is an internationally accepted method to assess the environmental impacts of a product or product system. With the collected and/or calculated inputs and outputs of the whole life cycle of a product or product system, LCA can be performed according to some standards (ISO 14040 and ISO 14044 [15,16]), in order to evaluate the related environmental impacts quantitatively. A complete LCA study includes four stages, goal and scope definition, life cycle inventory analysis (LCI), life cycle impact assessment (LCIA), and life cycle interpretation . The following explicitly explains the calculation and/or estimation methods used.
2.1. Goal and Scope Definition
The goal of an LCA study is related to its intended application and audience, while the scope of an LCA is related to the studied system. The goal of the present study is to get the fundamental data regarding the environmental impacts of ramie fibers. The scope of this study includes ramie cultivation and harvesting, peeling, transportation, degumming, carding and spinning (shown in Figure 1).
2.2. Functional Unit
The functional unit is specified to provide a reference to which the inputs and outputs are connected. As the specific modulus of the ramie fiber and glass fiber are both 29 × 105 m , the functional unit was defined as 1000 kg of ramie fiber, which can offer the same stiffness as glass fiber on a weight-for-weight basis. However, where the composites are concerned, the lower density of the ramie fiber would lead to an increasing use of polymers in the RFRP rather than in the GFRP, if the volume content of polymers in both FRPs is the same.
2.3. Allocation Principle
Allocation is very important during the performance of LCA, and different allocation methods and a different set up of the primary products would affect the final environmental burdens of the product or product system studied [8,18]. In the present study, the allocation was performed twice based on the mass ratio of primary products to the by-products. At first, the allocation was done in the ramie cultivation, harvesting, and peeling process, where raw ramie fiber was considered as the primary product and the ramie leaves, ramie stalk, and ramie bark (excluding raw ramie fiber) were considered as by-products. Also, in the carding and spinning process, allocation was performed again and long fibers were considered as a primary product, while short fibers and shives were considered as by-products.
The environmental impacts are characterized by eight categories, which are climate change, freshwater eutrophication, ozone depletion, human toxicity, photochemical oxidant creation and terrestrial acidification, freshwater ecotoxicity, and fossil depletion, and were allocated based on the principle stated above.
2.4. Life Cycle Inventory Analysis
The life cycle inventory analysis is the second step to complete a LCA. In this step, all of the inputs and outputs related to the processes within the scope need to be collected. According to the scope of the study, the inputs and outputs of the ramie cultivation, harvesting, peeling, transportation, degumming, and spinning processes need to be collected. The data used in this article comes from published papers, theses, websites, and also a ramie textile mill, named Hunan Huansheng Dongting Maye Company Limited, which is located in Yueyang city, Hunan province, China.
2.4.1. Inputs and Outputs of Ramie Cultivation, Harvesting, and Peeling
As for the inputs of ramie cultivation, there is no need for seeding after each harvesting, because ramie is a perennial herbaceous plant and cuttage propagation is the main method for planting ramie. Averagely 12.8 kg N, 3.2 kg P2O5, and 16.5 kg K2O are needed for producing 100 kg of raw ramie fiber [19,20]. To decrease the weeds, 7.5 kg diuron together with 40 kg water per hectare  are used, and 0.42 kg cyhalothrin together with 675 kg water per hectare are assumed to be used for reducing the number of pesticides. It is assumed that a chisel plough was used in winter for weeding once a year, and the amount of diesel consumed was set as 8.8 L/ha . The amount of diesel consumed by agricultural equipment for spraying agrochemicals was set as 1 L/ha . It is assumed that no irrigation was applied during the growth of ramie fiber.
Concerning the outputs of ramie cultivation, 3142.9 kg ramie leaves, 2357.1 kg ramie stalk, together with 1642.9 kg ramie bark (including raw ramie fiber) will be obtained when 1000 kg of raw ramie fiber is obtained . An average value (2337 kg per year per hectare) of raw ramie fiber yield was set according to the real situation in Hunan province, China, because Hunan province (central area of China) is the main ramie production area in China and the cooperative ramie textile mill is located in Hunan province. Table 1 shows the annual raw ramie yield of Hunan province from 2000 to 2016, with missed data of 2009–2014, which is reported by the ministry of agriculture, China . Moreover, the application of fertilizers will cause emissions of nitrogen gaseous fluxes and nitrogen leaching, which can be estimated according to Intergovernmental Panel on Climate Change (IPCC) tier 1 method . Also, the emission factors of cyhalothrin to air, water, and soil are set as 0.01, 0.005, and 0.013 . Phosphorus leaching was estimated according to the emission factor 0.01 . The emissions of producing fertilizers, pesticide, herbicide, and water were acquired from GaBi databases and the pesticide and herbicide used in GaBi software to compute the environmental impacts were an unspecific type.
The emissions from producing and the combustion of diesel are the main causes for environmental pollution in the ramie harvesting process. A 4 LMZ 160 crawler-type ramie harvester with 25.7 kW auxiliary power was used for harvesting the ramie fiber and its average harvesting rate is 0.15 hectare per hour . When the consumption of diesel used for harvesting was computed, the specific fuel consumption was set as 0.2448 kg/kW·h, according to the data sheet of T35 type of diesel engine (whose power is 24 kW) of Changchai Company Limited . As for diesel combustion, the emission factors of carbon monoxide, carbon dioxide, nitrogen oxides, sulfur dioxide, and non-methane volatile organic compounds (NMVOC) were set as 0.0291 g/kg, 3.04 g/kg, 0.0571 g/kg, 0.00415 g/kg, and 0.00916 g/kg, respectively .
As for the peeling process, generating electricity is the main reason accounting for emissions to the natural environment. A 6BZ-400 model ramie barker was assumed to peel the bark from the ramie stem, and its auxiliary power and peeling rate are 2.8 kW and 10 kg/h. The emissions of generating electricity were taken from GaBi.
An allocation was performed during this process based on the mass of raw ramie fiber, ramie leaves, ramie stalk, and ramie barks (excluding raw ramie fiber) and 14% of the environmental burdens were assigned to raw ramie fiber. The allocation was performed with the help of GaBi software. The biogenetic carbon storage of the ramie fiber was also considered in this work. The amount of carbon stored by the natural fiber depends on its cellulose content . The degummed ramie fiber mainly consists of cellulose, and according to the literature , and when 1 kg of natural fiber is produced, 1.5 kg CO2 would be absorbed.
Table 2 summarizes the inputs and outputs of producing 1000 kg of raw ramie fiber.
2.4.2. Inputs and Outputs of Transportation
The GaBi software contains almost all of the transport modes. In the present paper, the transportation process was modeled with GaBi. The transportation distance between the ramie field and the manufacturing factory is assumed as 50 km. A Euro 5 diesel truck with a 3.3 ton payload capacity was set to be the transportation method, considering the yield of the ramie fiber. Although the distance from field to factory is difficult to determine precisely, the environmental impacts of this process contribute very little to the overall environmental impacts, which can be seen from later parts.
2.4.3. Inputs and Outputs of Degumming Process
Because there are gummy matters (20–40% of the mass of raw ramie fiber), mainly composed of hemicellulose and pectin in raw ramie fibers , the raw ramie fiber cannot be used directly in FRPs until they are degummed. Degumming methods mainly include chemical, enzymatic, and microbial methods , and in the present study, enzymes together with chemicals (shown in Figure 2) were used to get the degummed fiber in this study.
The inputs of the degumming process were the chemicals (shown in Table 3) used to dissolve and remove the gummy matters, which were collected from the cooperative company mentioned above. It is known that, when 100 kg of raw ramie fibers were degummed, 60 kg degummed ramie fiber would be obtained, and 11 kg sulphuric acid, 20.25 kg sodium hydroxide, 2.4 kg hypochlorous, and 1.4 kg degumming agent would be consumed. The emissions for producing the chemicals used in this process were taken from the GaBi databases, except for degumming agent because of commercial confidentiality. As the dosage of the degumming agent is usually very small, the environmental impacts of producing and using the degumming agent have not been taken into consideration in this study. The environmental impacts of producing enzymes were not included in this paper, because of a lack of reliable data. A lack of data regarding the environmental impacts of hypochlorous acid, when the GaBi model was built, led to the use of calcium hypochlorite in order to produce hypochlorous acid, according to a chemical reaction among calcium hypochlorite, carbon dioxide, and water.
The outputs of the degumming process were mainly wastewater and it mainly comes from the pickling, boiling, washing, and bleaching processes. The wastewater from ramie degumming process usually has high pH value, high contents of chemical oxygen demand (COD), and biochemical oxygen demand (BOD). The wastewater cannot be discharged directly until it has been well treated. In this study, the wastewater treatment method was set based on the literature , in which a acidifying hydrolysis/biological oxidation/photochemical process method was utilized in a sewage treatment plant to make the wastewater meet the requirements of the national sewage discharge standard in China. To run the whole treatment process, electricity and chlorine need to be supplied constantly and the environmental impacts of producing electricity and chlorine were also within the system boundary in the present study. After treatment, the contents of COD, BOD, and sulfide were set as 300 mg/L, 100 mg/L according to the national wastewater discharge standard in China.
Table 3 shows the inputs and outputs for producing 1000 kg of degummed ramie fiber and the emissions of producing water, electricity, chlorine, sulphuric acid, and sodium hydroxide were taken from GaBi software.
2.4.4. Inputs and Outputs of Carding and Spinning Process
Degummed ramie fibers could be spun to get yarns, which were used to for the comparison to glass filaments. Before spinning, carding is necessary to get long degummed ramie fibers suitable for spinning, and short fibers and shives that could be used in other ways like building particle boards or animal beddings. Therefore, the allocation was performed again in this stage, based on the mass of long fibers and others. Based on the data from the cooperative factory, only 30% of the degummed fibers will be formed into yarns. The electricity consumption for the carding and spinning are based on the data for the flax fiber carding and spinning , because of no reliable data are available for ramie carding and spinning. Table 4 shows the inputs and outputs of the ramie carding and spinning process.
2.5. Life Cycle Impact Assessment (LCIA)
In the LCIA stage, the emissions and resource extraction will be translated into several environmental impact scores by multiplying the corresponding characterization factors. There are mainly two types of characterization factors, which are at a midpoint level and endpoint level, respectively.
In this paper, the ReCiPe method was chosen to model the environmental impacts of different fibers with the help of GaBi software. The environmental impact categories used to characterize the overall environmental performance of every fiber are climate change, terrestrial acidification, freshwater eutrophication, ozone depletion, human toxicity, photochemical oxidants creation, freshwater eco-toxicity, and fossil depletion.
The inputs and outputs of the processes involved in the scope of this study were used to build models in GaBi software.
Interpretation was the final step of an LCA study, and by interpretating the results from LCIA stage, the processes that have a high potential for pollution would be identified, and some useful conclusions and recommendations can be made.
3. Results and Discussions
Using the inputs and outputs from the LCI stage, the ReCiPe method and the eight main environmental categories to characterize the environmental performance of the ramie fiber, the LCIA results are shown in Table 5 and Figure 3.
As can be seen from Table 5 and Figure 3, when the environmental burdens of the ramie yarns were compared to that of the glass fibers, the ramie yarns only performed better in terms of ozone depletion, with a reduction rate of 98.29%. However, as for the other categories, the glass fibers are more eco-friendly compared with the ramie yarns. When the environmental performance of the ramie fibers (after carding and without spinning) are compared to that of the glass fibers, the ramie fibers (after carding and without spinning) perform better on ozone depletion, with a reduction rate of 98.37%, and it has almost the same values for climate change and terrestrial acidification compared to glass fiber.
Concerning identifying the processes that contribute the most to the overall environment pollution, as can be seen Table 6 and Figure 4, the degumming process and carding and spinning process are the main causes for massive environmental pollution. The percentages of the degumming process and spinning and carding process that contributes to climate change, terrestrial acidification, freshwater eutrophication, ozone depletion, human toxicity, photochemical oxidant formation, freshwater ecotoxicity, and fossil depletion is 65.2% and 58.3%, 76.9% and 20.4%, 74.2% and 0.28%, 94.3% and 5.05%, 81.4% and 17.5%, 79.2% and 18.8%, 68.7% and 0.95%, and 53.7% and 41.1%, respectively. The cultivation, harvesting, and peeling processes mainly contribute to freshwater eutrophication, ozone depletion, and freshwater ecotoxicity, and the negative value caused by these processes are due to the absorption of carbon dioxide. The transportation process contributes little to all eight of these categories, compared to other processes.
From the results above, it seems that the environmental performance of ramie fiber is not so competitive compared with glass fiber, especially when the spinning process was included into the whole manufacturing system of the ramie fiber. However, this idea may not be true. Because, at first, compared with the manufacturing technology of glass fiber, the production techniques of the ramie fiber are still not perfect and there is still a lot of room for improvement in the production techniques of ramie fiber. Then, there are no production techniques just for RFRP. For example, during the degumming process of the ramie fiber, when ramie fibers are used in FRPs, there may be no need for bleaching, which will reduce the consumption of sodium hypochlorite, washing water, and the releasing of treated wastewater. Then, the residual gum rate of the degummed ramie fiber should be less than 2% in the textile industry, while in the FRPs, the residual gum rate may be not so strict, which means that less chemicals may be used in the degumming process. Next, the spinning requirements for the textiles and FRPs may be different too. Finally, ramie fibers can degrade automatically, which can reduce the energy required for handling the disposals made of RFRP.
Based on the discussion above, more research should be performed to establish the manufacturing technologies of the ramie fiber just for RFRP. Degumming and spinning processes are the main processes that can be targeted to decrease the environmental burdens of ramie fibers used for FRPs.
Although some results have been obtained, there are also some limitations in this article. Firstly, the data used in the calculation is relatively limited, which means there will be more uncertainty regarding the final results. Then, data from the cooperative ramie textile mill was collected by the local workers in the mill, because of commercial confidentiality, which means there may be some variation because they know nothing about LCA principles. However, this study did provide some useful information and conclusions in general.
According to LCA, the input and output data of the production processes of ramie fibers were summarized and analyzed. The comparison of LCA between the ramie fibers and glass fibers were performed. The following conclusions can be drawn based on the above study.
According to the results of LCA, if the spinning process was included within the manufacturing of the ramie fiber, the ramie fiber performs better than glass fiber only in ozone depletion. If the spinning process was not included, the ramie fiber performs better in the ozone depletion and has almost the same values of climate change and terrestrial acidification.
The degumming, and carding and spinning processes are the main causes of pollution during the production of ramie fibers. The cultivation, harvesting, and peeling processes mainly contribute to the categories of freshwater eutrophication, ozone depletion, and freshwater ecotoxicity. The transportation process contributes little to the overall pollution.
More research should be done toward developing production techniques for the ramie fibers for the RFRP.
G.X. and X.-S.Y. conceived and guided the study; S.D. collected the data and wrote the paper.
This work was financially supported by the Chinese MIIT Special Research Plan on Civil Aircraft, grant No. MJ-2015-H-G-103 and European Union’s Horizon 2020 research and innovation programme, under grant agreement No. 690638.
Conflicts of Interest
The authors declare no conflict of interest.
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Figure 1. Production processes of ramie fiber.
Figure 2. Typical enzymatic degumming processes of ramie fiber.
Figure 3. Comparison between three different kinds of fibers in terms of the eight main environmental categories.
Figure 4. Percentages of different processes that contribute to the eight different environmental impact categories of ramie yarns.
Table 1. Yields of ramie fiber of 2000–2016 with missed data of 2009–2014 in Hunan province.
Table 2. Inputs and output of producing 1000 kg of raw ramie fiber.
|382.1 kg||Raw ramie fiber||1000 kg|
|69.6 kg||Ramie bark|
(excluding raw ramie fiber)
|275 kg||Ramie leaf||3142.9 kg|
|Diuron||9.6 kg||Ramie stalk||2357.1 kg|
|Cyhalothrin||0.5 kg||Carbon monoxide||1.7 g|
|Water||917.8 kg||Carbon dioxide||176.5 g|
|Electricity||280 kW·h||Nitrous oxide||5.4 kg|
|Diesel||58 kg||Nitrogen oxides||3.3 g|
|Sequestered atmospheric CO2||1500 kg||Sulfur dioxide||0.2 g|
|Emission of cyhalothrin to air||5 g|
|Emission of cyhalothrin to water||2.5 g|
|Emission of cyhalothrin to soil||6.5 g|
|Phosphate to water||0.14 kg|
This table does not include the inputs of the ramie rootstock and soil components consumed, which are about four tons. NMVOC—non-methane volatile organic compounds.
Table 3. Inputs and outputs of producing 1000 kg of degummed ramie fiber. COD—chemical oxygen demand; BOD—biochemical oxygen demand.
|Water||733 tons||Degummed ramie fiber||1000 kg|
|Electricity||1475.52 kW·h||Pectin, lignin, and hemicellulose||666.7 kg|
|Chlorine||8.8 kg||Wastewater (treated)||733 tons|
|Sulphuric acid||183.3 kg||COD||300 mg/L|
|Sodium hydroxide||337.5 kg||BOD||100 mg/L|
|Hypochlorous acid||40.0 kg|
|Ramie degumming agent||23.3 kg|
|Steam from biomass||16.7 tons|
|Raw ramie fiber||1666.7 kg|
Table 4. Inputs and outputs of producing 1000 kg ramie yarns.
|Electricity||7260 kW·h||Ramie yarns||1000 kg|
|Degummed ramie fiber||3333.3 kg||Short fibers and shives||2333.3 kg|
Table 5. Life cycle impact assessment (LCIA) results of one ton ramie yarns, ramie fiber (after carding), and glass fibers.
|Environmental Impact Category||Unit||Glass Fibers||Ramie Fiber|
|Climate change||kg CO2-Equiv.||1740||1770||3790|
|Terrestrial acidification||kg SO2 eq.||10.3||10.9||13.4|
|Freshwater eutrophication||kg P eq.||5.25 × 10−3||86.9 × 10−3||87.1 × 10−3|
|Ozone depletion||kg CFC-11 eq.||483 × 10−10||7.88 × 10−10||8.26 × 10−10|
|Human toxicity potential||kg 1,4-DB eq.||20.8||147||175|
|Photochemical oxidant formation||kg NMVOC||5.26||11.9||14.4|
|Freshwater ecotoxicity||kg 1,4-DB eq.||0.461||4.12||4.15|
|Fossil depletion||kg oil eq.||578||832||1.34 × 103|
Table 6. Values of the eight categories contributed by different production processes of ramie yarns.
|Environmental Impact Category||Unit||Transportation||Cultivation, Harvesting and Peeling||Carding and Spinning||Degumming|
|Climate change||kg CO2-Equiv.||31||−921||2210||2400|
|Terrestrial acidification||kg SO2 eq.||0.024||0.346||2.74||4.94|
|Freshwater eutrophication||kg P eq.||5.9 × 10−5||0.0125||24.1 × 10−5||0.027|
|Ozone depletion||kg CFC-11 eq.||0||5.30 × 10−12||41.7 × 10−12||738 × 10−12|
|Human toxicity potential||kg 1,4-DB eq.||0||1.8||30.6||63|
|Photochemical oxidant formation||kg NMVOC||0.0431||0.353||2.7||4.39|
|Freshwater ecotoxicity||kg 1,4-DB eq.||1.25 × 10−11||1.26||0.0395||2.51|
|Fossil depletion||kg oil eq.||1.4||67.6||550||701|
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The Life Cycle of the Hummingbird
Hummingbirds are a group of numerous and colorful birds that inhabit the American continent. These little beings are capable of living in a great variety of ecosystems, as they adapt quite well to the environment. In general, the life cycle of the hummingbird isn’t usually complex, but it does have impressive characteristic features.
Hummingbirds belong to the Trochilidae family, in which there are about 330 species. This group can inhabit places as far-ranging as beaches, coasts, jungles, forests, and mountains, as well as arid or urban environments. Read on to learn more about these beautiful birds and their way of life.
What are hummingbirds like?
All hummingbirds are small birds that weigh between 2 and 24 grams and are characterized by the shape of their beaks and their amazing way of flapping. Their feet are so small that they don’t even allow them to walk on the ground, which means that they spend most of their lives flying. In addition to this, most of them exhibit iridescent plumage that is extremely attractive to the eye.
The members of this group are nectarivores, which means that they feed on the nectar of flowers. For this reason, the beaks of hummingbirds are elongated and thin, because if they weren’t they wouldn’t be able to drink in the liquid. In fact, thanks to this they’re also considered to be excellent pollinators, as they impregnate and transport pollen during their meals.
These birds are distinguished by their extraordinary flying ability; they’re able to stay suspended in the air or fly in any direction. To accomplish this feat, they need powerful muscles that allow them to flap 80 to 200 times per second. Thanks to this machinery, they reach speeds of between 50 and 90 kilometers per hour (30-55 miles per hour).
The ability to flap consumes large amounts of energy, and so their metabolism has adapted to this situation. The speed with which the hummingbird processes its nutrients is so incredible that each specimen has to consume half its body weight in food per day. Also, the speed with which it metabolizes food causes it to experience body temperatures of almost 40° C.
The life cycle of the hummingbird: migration
Some species in this group show a migratory behavior in which they cross great distances to reach warmer areas during winter. These movements can be a great challenge for these birds, as they need to consume large quantities of food for the amount of energy they use. When spring arrives, they fly back to their territories to begin their reproduction.
An impressive example is that of the Rufous Buzzard (Selasphorus rufus), as it travels approximately 3,500 kilometers (2170 miles) from Alaska to southern Mexico. These trips are possible thanks to the multiple stops it makes during its journey.
Reproduction of hummingbirds
The males are usually quite aggressive and territorial, so when they return from their migration they compete with others to establish their limits. Usually, the male of the species returns a week or two before the female to the breeding area in order to take up the best space and the greatest amount of resources.
Courtship and mating
When the female returns from her migration in spring, the mating season begins. During it, the male performs a showy and energetic courtship that consists of ascending and descending flights in a U-shape in which it displays its plumage. In addition to this, it also performs vocalizations and flaps as quickly as possible in order to attract the attention of its potential partner.
For her part, the female bases her choice on two main aspects: the characteristics of the male and the territory he occupies. It’s important for the female to have a secure food supply (as her life and that of her young will depend on it), so she takes this aspect seriously.
In general, these small birds have polygamous mating, so the male usually has several reproductive partners. For this reason, most of the rearing and building of the nest are the female’s tasks, which causes her to be so selective in the choice of her mate.
Hummingbirds are oviparous animals that use nests to hatch their eggs. These constructions have different sizes according to the species, although most are as small as a golf ball. To make it, the females make use of branches, leaves, cobwebs, lichens, and mosses. Similarly, they choose their location (close to the ground or high in the trees).
Egg-laying, incubation, and rearing
The number of eggs a hummingbird can lay varies between species, but on average it’s usually 2 per nest. For its part, the incubation time ranges from 18 to 20 days, during which the female remains in the nest for as long as possible.
The baby hummingbirds emerge from the eggs at the end of incubation and it’s at this time that the mother begins to feed them with nectar and insects. As in other birds, females nurture their chicks by regurgitation.
The young remain in the nest while their feathers grow and until they’re capable of flight, which could last approximately 3 weeks. The moment they learn to fly, the chicks begin to look for their own food and begin their independence. However, to ensure that they’ll not starve, the mother could continue to feed them during their first days outside the nest.
The life cycle of the adult hummingbird and its survival
Once independent, the adults leave their nest and never return. A hummingbird’s first year is usually the hardest of its life, as it faces other large and strong creatures. Despite this, once they leave the nest, the probability that they’ll die is quite low, since most deaths occur during incubation.
During the life cycle of the hummingbird, this organism has to avoid a series of dangers that cause its death in the first months of age. For this reason, experts tell us that most hummingbirds die before reaching one year of age. However, the average life of a hummingbird can be 6 or 7 years (or a maximum of 10).
Contrary to what one might think, the frenetic life these birds live doesn’t affect their quality of life. This shows that the adaptation of these birds is beyond our imagination, and that they exhibit unique characteristics without any negative consequences. Despite their size, hummingbirds are undoubtedly one of the most curious and beautiful birds in nature.
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