bluuebunny/crossref_metadata_2025_split huggingface dataset:
Snow Density
Authors: Singh Pratap 
Published: April 2005

Abstract

Density is one of the fundamental and important characteristics of snow. It is defined as the mass of snow per unit volume. To determine the density of snow, a core sample of snow is extracted from the accumulated snow on the ground using a snow sampler of known volume. The extracted snow sample is weighed and its mass is determined. The density of the sampled snow is determined by dividing the mass by the volume. The most common unit used for representing the density is g/cc or kg/m
3
.
U
nited
S
tates
W
eather
B
ureau
Authors: Holst Arthur M. 
Published: April 2005

Abstract
From 1890–1970, the United States Weather Bureau provided various weather‐related services to the nation. Weather analysis had been considered for hundreds of years, but real progress was not made until the nineteenth century, when techniques and technology began to make accurate and useful weather forecasting possible, the main purpose of the United States Weather Bureau, its predecessors, and its successor, the National Weather Service. The first national American weather service was initiated on February 9, 1870, when President Ulysses S. Grant signed into existence what was then known as The Division of Telegrams and Reports for the Benefit of Commerce. This service began in November 1870. It lasted until 1890, when it was renamed the United States Weather Bureau, and Congress reassigned it from the Department of War to the Department of Agriculture at the behest of President Benjamin Harrison. Then, in 1940, President Franklin Delano Roosevelt reassigned the Weather Bureau again, this time to its current home, the Department of Commerce. The United States Weather Bureau existed until 1970, when its name was again changed, this time by President Richard Nixon, to the National Weather Service, the name it is known by today.
Degree Day Method
Authors: Messina Carlos D. 
Published: April 2005

Abstract
An adequate description and prediction of plant development is critical for understanding plant growth and its responses to the environment. Only then we can assess the impact of a changing environment on plant productivity and survival, understand plant adaptation, design adequate agricultural production systems, and optimize natural resources management. Of particular importance for water resource management are the effects of plant ontogeny on plant water use and productivity throughout the regulation of leaf area. This determines the patterns of plant water demand and the partitioning between transpiration and evaporation components. Therefore, plant development dictates the selection of cultivars that best fit the water availability patterns under dryland conditions, and the amount, frequency and timing for irrigation otherwise.
Fluoridation
Authors: Dodes John E. 
Published: April 2005

AbstractFluoridation of water supplies has been a controversial subject for more than 60 years. Much of the debate is concerned with questions of safety, but recently questions have been also raised about the efficacy of fluoridation. More than 35,000 papers on fluoridation have been published in the years since fluoride supplementation was first proposed as a safe and effective way of decreasing tooth decay. The overwhelming conclusion is that fluoride is safe and cost‐effective.
Granular Bed and Precoat Filtration
Authors: Au Kwok‐Keung 
Published: April 2005

AbstractVarious filtration processes are used in potable water treatment. Granular bed and precoat filtration processes are described in this article, and focus is on descriptions of these processes and their particle removal efficiencies. Filtration processes are some of the major tools that are used to minimize microbial pathogens in drinking water, so the descriptions of their removal efficiencies contained herein emphasize their removal of microbes. This type of efficiency is characterized by a term called log removal, which is defined as logCo/C, whereCoandCare the pathogen concentrations in a filter's inlet and outlet flows, respectively. Thus, a 1‐log removal is equivalent to 90% removal. Current drinking water regulations target log removals of pathogens. Filter performance is also based on the amount of turbidity in the filtered water. Turbidity is a measure of water clarity. Turbidity reduces the aesthetic acceptability of drinking water and also shields pathogens from disinfectants that are added downstream of filters.
Lime–Soda Ash Processes
Authors: Viadero Roger C. 
Published: April 2005

Abstract

As in other chemical water softening technologies, the objective of the lime–soda ash process is to precipitate polyvalent cations from solution by pH adjustment. In water treatment applications, Ca
2+
and Mg
2+
are the two major cations of concern, though Fe
2+
, Fe
3+
, Al
3+
, and Mn
2+
may also be present at problematic concentrations, depending on the properties of soil or geological material encountered by the surface or groundwater. Typically, a total hardness ranging from 75–120 mg/L as CaCO
3
, is sought in domestic water softening.

In this process, lime and soda ash are added to solution, Ca
2+
precipitates as CaCO
3
(↓), and Mg precipitates as Mg(OH)
2
(↓). To precipitate CaCO
3
, the pH of the water must be raised to approximately 10.3. Similarly, Mg(OH)
2
(↓) forms when the pH is raised above 11. When there is not enough naturally occurring bicarbonate alkalinity (HCO
3
−
) in water to form the CaCO
3
precipitate, alkalinity must be added (typically as Na
2
CO
3
).
Microbiological Concerns of Drinking Water Distribution Systems
Authors: Karim Mohammad R. , Lechevallier Mark W. 
Published: April 2005

AbstractDrinking water in a distribution system may contain microbes that enter the distribution system through treatment breakthrough, regrowth, or contamination of water in the system. The majority of these organisms are harmless. However, pathogenic organisms may also be present. A number of waterborne disease outbreaks related to distribution systems have been reported. Many factors contribute to the regrowth and contamination of drinking water in distribution systems. This article discusses the factors that contribute to microbial regrowth and contamination of distribution systems. To ensure protection of public health, these factors should be adequately addressed to safeguard drinking water from contamination in distribution systems.
Removal of Pathogenic Bacteria, Viruses, and Protozoa
Authors: Au Kwok‐Keung 
Published: April 2005

AbstractPathogenic bacteria, viruses, and protozoa can be removed from potable water by various processes. These removal processes can be categorized into three groups: (1)initial, (2)principal, and (3)alternative/supplemental. Initial removal processesare used to remove microbial pathogens before they enter or as they enter a treatment plant. The main objective of these processes is to reduce the particulate loadings, including microbial loadings, to the subsequent treatment processes of a treatment plant. Examples of initial removal processes are roughing filters, microstrainers, off‐stream storage, bank filtration, and presedimentation with coagulation.Principal removal processesare those most frequently used to remove the majority of the microbes in the water being treated. These processes are sedimentation, flotation, and high‐rate granular media filtration. They are often used in conjunction with coagulation and flocculation.Alternative/supplemental removal processesare used either as (1) alternatives to principal removal processes or (2) supplemental processes to enhance drinking water quality. These processes include slow sand filtration, precoat filtration, membrane filtration, bag filtration, and cartridge filtration.
Pharmaceuticals in Water Systems
Authors: Pollack Kelly , Ogunseitan Oladele 
Published: April 2005

AbstractAs the demographic pattern in most regions of the world changes in response to epidemiological transition, life expectancy is lengthened, and human reliance on medications to maintain the quality of life intensifies. It is now indisputable that widespread use of pharmaceutical products results in their release into the environment. This occurs primarily through the excretion of partially metabolized doses and the disposal of expired or unused medication. It is inevitable that that these fugitive releases lead to exposures of aquatic organisms and other natural ecosystem components. However, the driving force behind recent concerns is the potential for large‐scale human exposures through natural drinking water recycling processes. Historically, most investigations of anthropogenic chemicals in the environment have focused on acutely toxic industrial chemicals from mining, energy, and agricultural industries. The environmental impacts of products emanating from the pharmaceutical industry have largely been excluded from scrutiny. The U.S. Geological Survey conducted the first national survey of pharmaceutical products in natural water systems in 2000. The results of that study confirmed prior suspicions about the widespread contamination of aquatic systems by these products.
Physical Water Conditioning
Authors: Sanderson Charles H. 
Published: April 2005

AbstractMagnetic water treatment technology that was used two centuries ago to control hard water scale is now being used in hundreds of different kinds of beneficial applications throughout the world. Permanent magnetic water conditioning (PMWC) does not change the chemistry of the water; only aphysicalchange takes place. It is therefore referred to as physical water conditioning.Physical water conditioning (PWC) has been highly controversial for many years; however, due to numerous successful installations on boilers, cooling towers, and other HVAC equipment, the technology has gained credibility throughout the industry in recent years. The ASHRAE Handbook (considered the “bible” of the industry) states, “Equipment based on magnetic, electromagnetic, or electrostatic technology has been used for scale control in boiler water, cooling water, and other process applications.” Several laboratory tests have been conducted to evaluate the results of magnetically treated water for scale and corrosion control in heat transfer equipment.When water flows through a magnetic field of relatively low intensity, the formation of scale in the treated water is prevented in many instances.
Public Water Supply World
Authors: Buenfil‐Rodriguez Mario O. 
Published: April 2005

AbstractIn cities of high housing densities,public water supplystarted as a measure to improve hygiene and health, as well as a need for fairness among citizens, to give them an equal chance to have water and to pay similar amounts via taxes or equivalent. It is also much cheaper and less chaotic to have collective solutions than individual ones.A public water service can concentrate and pay specialized personnel, devoted full time to these highly technical matters of searching, treating, transporting, raising, distributing, maintaining, and charging for water service.Water service in most cities of the world is provided by governmental institutions (either national. regional. municipal), but in many other locations is operated by private utilities. There also exist mixtures of private and governmental (public) responsibilities. Nowadays, there is a tendency, often promoted by lending institutions, to give up (“privatize”) governmental services that have too many conflicts and poor quality.In this article, the term “public water supply” refers to the water service provided by some official concessionaire (independently if is private or government) that attends to the needs of various clients in a city.
A Real‐Time Hydrological Information System for Cities
Authors: Hung M. Eng Nguyen Quang , Weesakul Sutat , Weesakul Uruya , Chaliraktrakul Chavalit , Mark Ole , Larsen Lars Chr 
Published: April 2005

AbstractNowadays, many organizations collect hydrologic information for various purposes. But still, little information from the huge sources of data is made public in real time, and only a small fraction of the data is applied for real‐time decision making. Once the hydrologic data have become “historical” (the data are no longer applicable for real‐time decision making), the data are still very valuable for design and for evaluating and understanding the hydrologic environment. But if hydrological data are used only after they have become “history,” the value of the data collection is not fully used.Before starting to disseminate hydrologic information it is important to address the following questions:What kind of real‐time information should be shown to the public?How and where should the real‐time information be presented to the public?When do hydrologic data change from valuable real‐time information to less interesting (from a public point of view) historical hydrologic data?What does it take in knowledge, technology, and hardware to provide real‐time hydrologic information?This article discusses experience gathered from a research project in Bangkok concerning provision of real‐time rainfall data to the public through the Internet, hand‐held computers, and mobile phones. It also provides an outline of the future use of hydrologic information in real time. The potential benefits from the described framework for using the information area public rainfall and flood information service, like the daily weather forecast, and flood warning systemtraffic information about streets that have a potential risk for flooding,a decision support system for reducing flooding in the Bangkok area.
Reverse Osmosis, Membrane Cleaning
Authors: Ning Robert Y. 
Published: April 2005

AbstractReverse osmosis membrane cleaning has been extensively addressed over the years. Severe concentration of dissolved and suspended matter occurs when water is purified by using reverse osmosis (RO) membranes. Permeate recoveries of 50–90% correspond to 2–10‐fold concentrations in the reject brine. Precipitation or crystallization of foulants can occur in the narrow brine flow channels within the membrane elements, leading to reduced membrane flux or increased differential pressure across the system, or both. Crystallization of salts or precipitation of colloidal matter occur more toward the back end of the system, and preexisting silt and flocculated organic matter can clog the leading elements of the system.
Water Disinfection Using
UV
Radiation—A
S
ri
L
ankan Experience
Authors: Ratnayake Niranjanie 
Published: April 2005

Abstract

UV radiation has been established as an effective bactericide and viricide. UV radiation penetrates the cell wall and is absorbed by cellular nucleic acids. Radiation absorption prevents replication, thus killing the cell. However, the effectiveness of UV radiation in killing spore forming bacteria such as
Giardia lamblia
has not yet been established. UV radiation is not a chemical agent, so it produces no toxic residuals.

A special lamp is used to transfer electromagnetic energy to the target organism's cells. Mercury arc lamps are the most commonly used type of lamp because about 85% of the energy output is of the 253.7 nm wavelength, which is within the optimum germicidal range of 250–270 nm.
The effectiveness of radiation is a direct function of the energy dose absorbed by the organism, which is measured as the product of the lamp's intensity and the time of exposure. Intensity is the rate at which photons are delivered to the target organism. It is governed by the lamp's power, the depth of water, and the presence of substances that absorb the energy, such as suspended solids, color, turbidity, and soluble organic matter. The radiation dose absorbed by the water is the water's UV demand (which is similar to the chlorine demand) and is quantified as the absorption of UV energy (wavelength 253.7 nm) in a given depth of water. The energy dose also depends on the exposure time of the water to the UV radiation, although the required time is only seconds, rather than minutes, for effective disinfection. However, water that has high concentrations of substances like suspended solids, color, turbidity, and soluble organic matter may not receive an adequate radiation dose for effective disinfection.
Water Meter
Authors: Buenfil Rodriguez Mario O. 
Published: April 2005

Abstract
Most modern water‐meters act on the principle of counting the number of turns made by a small reaction turbine moved by the water as it flows through it. This is the basis of Sir William Siemens' invention, who patented his water meter (‘fluid meter’) in April 1852 (1). Until that time, water metering was not possible; several attempts had been made to devise a suitable device, but all had failed. W. Siemens also invented meters for other applications (bathometer for the depth of the sea, electric pyrometer, etc.).
Ironically, England, where meters were invented, remains until now one of the few countries where almost no houses have water meters installed. This gives an idea of the complexity and expense of installing and reading them, particularly when they are not really indispensable (the United Kingdom: has a relatively good quantity of rain and water to waste, but it is not the same in other countries).
Nowadays, water meters, instead of mechanical transmission of movements and signals (as in old clock gearing), send magnetic, electric, or digital pulses which can be stored (remote dial counter or display, data‐logger, etc.)
Quantification of Anoxia and Hypoxia in Water Bodies
Authors: Nürnberg Gertrud K. 
Published: April 2005

AbstractHypoxic conditions (dissolved oxygen, DO, concentration below saturation) are widely spread in freshwater and saline environments. Especially in recent years, anthropogenic impacts have led to severe increases in estuarine and coastal anoxia [e.g., Gulf of Mexico and European coast‐lines]. Diaz describes 44 marine areas of moderate to severe hypoxia worldwide. Hypoxia and anoxia (lack of oxygen or zero concentration of DO) may even be more established in the freshwater environment, where it can occur naturally in lakes or not and where recent increases in organic and nutrient loading and changes in water flow have increased oxygen depletion in lakes, reservoirs, and large rivers.
Tidally Mediated Changes in Nutrient Concentrations
Authors: Magni Paolo , Montani Shigeru 
Published: April 2005

Abstract
Freshwater runoff during ebb flow and salt water intrusion during the flood may have a major effect on short‐term changes in nutrient (ammonium, nitrate+nitrite, phosphate, and silicate) concentrations along an estuary. Time series hourly measurements conducted in a mixed‐semidiurnal type estuary (i.e., characterized by two major lower and higher tidal levels) show that these changes are a strong function of both tidal state (e.g., low vs. high tide) and amplitude (e.g., neap vs. spring tide). In particular, the changes in nutrient concentrations are higher during ebb than during flood tide and largest between the lower low tide and the higher high tide of a spring tide. Finally, the importance of investigating simultaneously different stations along the estuarine spine is highlighted, in addition to studying the nutrient distribution based on selected salinity intervals which may reflect only the conditions at a particular tidal state.
Temporal Scaling of Benthic Nutrient Regeneration in Bivalve‐Dominated Tidal Flat
Authors: Magni Paolo , Montani Shigeru 
Published: April 2005

Abstract

Beside light and temperature, nutrients such as ammonium (NH
4
+
‐N), phosphate (PO
4
3−
‐P), and silicate [Si(OH)
4
‐Si] are a key factor in controlling the growth, abundance, and structure of primary producers in the ocean. Hence, it is important to investigate the availability, sources, and distribution of these nutrient species, as well as their spatial and temporal scaling. Biological processes strongly influence nutrient regeneration in different marine systems. In the open ocean, an important portion of reduced N‐forms (e.g., NH
4
+
‐N), for instance, is made available
in situ
from waste products of plankton metabolism and supports the so‐called “regenerated” primary production. In coastal marine ecosystems, benthic nutrient regeneration is a major driving force in cycling biophilic elements (e.g., N, P, and Si) and abundant macrofauna, for example, dense assemblages of bivalves, it has been shown, play a major role in these processes.
Physical and Chemical Variability of Tidal Streams
Authors: Magni Paolo , Montani Shigeru 
Published: April 2005

AbstractThis article focuses on the variability of major hydrologic parameters of tidal streams that occur on different temporal and spatial scales within an individual estuary. Rapid changes in water temperature and salinity take place on a timescale of <1 hour, as a strong function of the tidal state (e.g., low vs. high tide) and amplitude (e.g., spring vs. neap tide). Large day–night fluctuations of dissolved oxygen (DO) concentration are also demonstrated and discussed in relation to the extent ofin situbiological processes. In addition, the variability of these parameters is evaluated seasonally at controlled low tide. Finally, the year‐round distribution of nutrient concentrations (i.e., ammonium, phosphate, silicate, and nitrate+nitrite) in low tide ebbing water is presented and compared with the variability in nutrient concentrations in the sediment porewater of an adjacent exposed sandflat.
Laboratory Experiments on Bivalve Excretion Rates of Nutrients
Authors: Magni Paolo , Montani Shigeru 
Published: April 2005

AbstractBenthic nutrient regeneration may be referred to as a new availability to the water column of significant amounts of nitrogen, phosphorus, and other nutrients, as a consequence of the metabolism of organic matter by the benthos. The processes of benthic nutrient regeneration in coastal marine systems are strongly influenced by the presence of abundant macrofauna. Correct evaluation of the biogenic flux of nutrients due to the excretory activity of infaunal species is therefore an important background of information to investigate the cycling of biophilic elements (nitrogen, phosphorus, and silicon).
Deuterium
Authors: Kazemi Gholam A. 
Published: April 2005

Abstract

The hydrogen atom is believed to have been created during the “Big Bang” by proton–electron combinations (2). Together with an oxygen atom, it forms the water molecule and has three isotopes:
1
H (common hydrogen),
2
H (deuterium, D), and
3
H (tritium, T). Deuterium, discovered by Urey et al. (3) in 1932, is much heavier than
1
H. Common hydrogen has one proton, deuterium has one proton and one neutron, and tritium has one proton and two neutrons. Deuterium (also referred to as the heavy stable isotope of hydrogen) and common hydrogen are stable, but tritium is radioactive. In seawater, the relative abundances of hydrogen isotopes are H (99.984%), D (0.016%), and T (5 × 10
−5
%) (1). In the hydrosphere, there is only one deuterium atom per 6700 H atoms (4). Note that the arena of this article is limited to deuterium as it is a part of the water molecule. Hence, deuterium that may exist in other materials such as methane will not be dealt with here.