bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual Nonlinear Feedback Control of Liquid Level in Mold Sprue Cup by Cascade System with Flow Rate Control for Tilting-Ladle-Type Automatic Pouring System
Authors: Ito Atsushi , Oetinger Philipp , Tasaki Ryosuke , Sawodny Oliver , Terashima Kazuhiko
Published: June 2018

This paper presents the novel approach of liquid level control of mold sprue cup using camera information for tilting-ladle-type automatic pouring system in casting industry. A liquid level in mold sprue cup should be kept at high position to avoid inclusion of oxides and dusts during pouring process. A cascade control system with double feedback loop to enhance control response was proposed for the present level control: inner loop was the flowrate control system for pouring ladle, and outer loop was the level control one with camera measurement to detect the liquid level. The control part of flow rate was constructed based on the past study. The mathematical model of liquid behavior in a sprue cup of an inverted cone shape was built in this paper. The level controller was newly designed based on nonlinear control theory by exact linearization. The effectiveness of the proposed cascade system was verified by control simulations.
Diffractografic Analysis of AISI 420 Steel
Authors: Achiţei Dragoş Cristian , Minciună Mirabela Georgiana
Published: June 2018

The paper presents a study on the structure of AISI 420 steel after heat treatments. The experiments start with a spectral analysis for determination of percents for alloying elements. Based on obtained results was establish of heat treatments parameters, which can be applied on AISI 420 steel. By thermal processing can be influenced positive on structural modifications and implied on mechanical properties. Structural modifications were highlight by X-ray diffraction analysis.
Synthesis, Characterization and Crystal Structure of Coordination Polymers Developed as Anion Receptor
Authors: Kadir M.A. , Sumby Christopher J.
Published: June 2018

Reaction of diamide ligand, namelyN,N’-2,6-bis (4-pyridylmethyl) pyridine dicarboxamide (L) with cadmium nitrate and cadmium perchlorate has given rise to the formation of two types coordination polymers. Compound (CP1-Cd) with formula molecule {[Cd (L)2(H2O)2](NO3)2·6H2O}nis a one-dimensional coordination polymer while compound (CP2-Cd), with formula molecule {[Cd (L)2(H2O)2](ClO4)2·31⁄2H2O.CH3OH}n, is a two dimensional coordination polymer. These coordination polymers were preparedviaslow evaporation methods and completely characterized by combination of solid state techniques such as Fourier Transform Infrared (FTIR) spectroscopy, elemental analysis and X-ray crystallography. This study revealed that coordination polymers derived fromN,N’-2,6-bis (4-pyridylmethyl) pyridine dicarboxamide can accommodate anions with different sizes, showing good potential as anion receptor.
Formation of Cu6Sn5/(Cu, Ni)6Sn5 Intermetallic Compounds between Cu3Sn-Rich Sn-Cu/Sn-Cu-Ni Powdered Alloys and Molten Sn by Transient Liquid Bonding
Authors: Somidin Flora , McDonald Stuart D. , Nogita Kazuhiro
Published: June 2018

This paper presents the use of the transient liquid phase concept to grow the high temperature Cu6Sn5intermetallic compound between Cu3Sn-rich powdered alloys and molten Sn. In this study, high temperature powdered alloys containing high fractions of Cu3Sn were fabricated from a chill-cast Sn-60 wt.%Cu alloy. A ternary alloy with composition of Sn-59 wt.%Cu-1 wt.%Ni was also prepared to investigate the effect of Ni. The reaction products were obtained at 250°C over a period of 30 minutes. The results provide new insight into the mechanism of the interfacial reaction between liquid Sn and solid Cu3Sn-rich alloy with and without Ni additions.
Manganese Substituted Iron Titanate Particles with Enhancement Adsorption Capacity for Removal of Remazol Brilliant Blue R Dye
Authors: Abdul Aziz Azia Wahida , Mat Amin Khairul Anuar , Razali Mohd Hasmizam
Published: June 2018

Manganese substituted iron titanate was successfully synthesized and characterized by x-ray diffraction and Fourier transformed infra-red to investigate the composition and to identify the chemical compound of this unique architecture. The materials were tested for adsorption of remazol brilliant blue R (RBBR) aqueous solution. The adsorptions were investigated at different pH which are pH 3, 4, dye concentration and manganese substituted iron titanate dosage. It was found that synthesized manganese substituted iron titanate particles can adsorbed 99% of 100 ppm RBBR dye at pH 2.
The Formation and Properties of Zeolite-A and Zeolite-X through Geopolymerisation of Metakaolin
Authors: Subaer  , Fansuri Hamzah
Published: June 2018

This study was aimed at experimentally investigate the formation of zeolite-A and zeolite-X through geopolymerization routes. The samples were prepared by alkali-activation of metakaolinite at 70 °C with Si:Al = 1.04 and 1.25 and Na:A l= 0.6, 0.8, 1.0 while keeping the molar ratio of H2O:Na2O = 10. The physical and mechanical properties of the resulting materials were characterized by means of bulk density and porosity measurement, compressive strength and Vickers microhardness tests. Crystallinity level and the phase of the samples was examined by X-Ray Diffraction (XRD) while morphology and elemental composition of the samples were examined by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). It was found that zeolite-A and zeolite-X were able to produce through geopolymerisation of metakaolin. XRD and SEM-EDX analysis results showed that these materials were composed of zeolite-A or zeolite-X together with amorphous geopolymer. The zeolite X was only formed when ratio of Si:Al is 1.25 while zeolite A was formed at all ratio except ata Si:Al=1.25 and Na:Al=1.0. These materials have relatively low hardness and compressive strength, low density and high apparent porosity.
Effect of Geopolymer Coating on Mild Steel
Authors: Zainal Farah Farhana , Fazill Muhammad Faiz , Hussin Kamarudin , Rahmat Azmi , Abdullah Mohd Mustafa Al Bakri , Wazien Warid
Published: June 2018

This paper presents the results of a study on the effect of geopolymer coating on mild steel. Geopolymer is synthesis of a fly ash and alkaline activators which are sodium hydroxide solution (NaOH) and sodium silicate solution (Na2SiO3). Fly ash is one of residue produced during the combustion of coal in coal power plant. In this study, fly ash class F based geopolymer was used as a source material. The alkaline activators then were mixed with fly ash to produce the geopolymer paste which acts as a coating material. The mixture was placed in molds and reinforcement bar were embedded in geopolymer paste. After that, the corrosion behavior of reinforcement bars for all samples were observed by using Open Circuit Potential (OCP) testing. Referring the pourbaix diagram regarding OCP testing, samples are in passivity region. Besides that, mild steel also were coated with geopolymer paste for adhesion test. Elcometer 108 was used for adhesion strength test. Morphology analysis also been used to determine the microstructure of fly ash and geopolymer paste. Phase analysis was used for the analysis phase between fly ash, geopolymer paste and mild steel coated with geopolymer paste. From OCP test, pourbaix diagram shows that samples is placed in the passivity region, iron (III) oxide (Fe2O3) which is in stable phase and iron (II, III) oxide same results as in phase analysis. The minimum potential value for OCP is 0.015 V and the maximum potential value is 0.133 V. For adhesion strength, day 14 got the highest results compared day 7 and day 3 which the results are 2.0 Mpa, 1.9 Mpa and 1.5 Mpa respectively. It is because from day 3 until day 14, the structure of geopolymer paste becomes more compact, denser and better crystallization as shown in morphological analysis.
Brazing Sapphire/Sapphire and Sapphire/Copper Sandwich Joints Using Sn-Ag-Ti Active Solder Alloy
Authors: Feng Kui Yuan , Mu De Kui , Liao Xin Jiang , Huang Hui , Xu Xi Peng
Published: June 2018

In this paper, a preliminary study in the wetting behavior and interface reaction between active Sn-Ag-4Ti solder alloy and C-plane sapphire was given. An in-situ observation of Sn-Ag-4Ti alloy on C-plane sapphire revealed a decrease in contact angles at temperature close to 550°C. Moreover, sapphire/sapphire and sapphire/copper sandwich joints were brazed using Sn-3.5Ag-4Ti alloy at 500 oC, 550°C and 600 °C to investigate the microstructure evolution and interface reaction. Microstructure characterization and element analysis indicated that the temperature affected the diffusion of active Ti element by modifying the formation of Sn-Ti intermetallics compounds in Sn-Ag-Ti solder alloy. The absorption of Ti together with the release of Al from sapphire suggested the interface reaction between Sn-Ag-Ti alloy and sapphire was triggered at 550°C.
Influence of Bismuth in Sn-Based Lead-Free Solder – A Short Review
Authors: Razak Nurul Razliana Abdul , Mohd Salleh Mohd Arif Anuar , Saud Norainiza , Said Rita Mohd , Ramli Mohd Izrul Izwan
Published: June 2018

Since the implementation of RoHS in avoidance to useof lead in electronic packaging, the development of lead-free solder has become priority. However, some of the potential candidates for lead-free solder have weaknesses such as slightly higher of melting point, excessive of intermetallic growth (IMC) and uncertainty service reliability that need to overcome. One of the common methods used to improve the characteristic and properties of the lead-free solder is by the addition of another alloying element. One of the promising alloying elements is bismuth (Bi). A few researchers have found out that Bi has a capability to improve the microstructure, reduce the melting temperature and controlled the IMC growth, yet, its advantageous is believed have not been thoroughly explored. Influence of (Bi) in lead-free solder alloys give interest to be studied and understand from different perspective due to its capability to improve the wettability and solder spread, and also reduce the melting temperatures of the solder. In this paper, a review on influence of Bi inSn-based lead-free solder and its advantageous were discussed.
Microstructure and Phase Analyses on the Corrosion of SAC305 Solder in NaСl Solution
Authors: Mohd Zaini Nurwahida , Mohtar Mukridz Md , Mohamad Ahmad Azmin , Mohd Nazeri Muhammad Firdaus
Published: June 2018

Utilization of Sn-3.0Ag-0.5Cu to replace toxic lead-based solder was only feasible if the corrosion performance of this solder was assured. To obtain this information, potentiodynamic polarization was implement in 3.5 wt. % NaCl. The morphological and structural changes were investigated via crucial characterization methods (SEM and XRD). Collective evidences verified that the needle-like corrosion product confirmed to be made ofSnO, SnO2and SnCl-and responsible to passivation behavior of this solder.
Forming of the Structure and Functional Properties of the Precipitation-Strengthened CuNi2Si1 Alloy
Authors: Konieczny Jarosław , Rdzawski Zbigniew
Published: June 2018

The work presents the results on the structure of CuNi2Si1 copper alloy. The alloy was treated in two variants: supersaturation - aging (variant I) and supersaturation - cold rolling - aging (Variant II).The structure of the CuNi2Si1 alloyed copper were analyzed by high resolution transmission electron microscopy (HRTEM). The TEM investigation showed in the Cu matrix after applying cold rolling after solution heat treatment, during aging at 600°C, causes the Ni2Si phase occurrence immediately after the begin of aging. Cold rolling (50% reduction) of the CuNi2Si1 alloy after supersaturation changes the mechanism and kinetics of precipitation and provides possibilities for production of broader sets of functional properties.
Instability of Plastic Deformation in Low-Alloy Copper Alloys
Authors: Grzegorczyk Barbara
Published: June 2018

The purpose of this paper is to determine the influence of temperature of plastic deformation on the structure and mechanical properties of copper alloys of the types CuCo1NiBe (CCNB), CuCo2Be (CB4), CuNi2SiCr (CNCS), CuNi1P (CNP) and CuCr1Zr (CW106C) applied on electrodesduring a tensile test. Tensile tests were carried out on polycrystalline samples of above mentioned alloys, which confirmed the presence of inhomogeneous plastic deformation in specified temperature ranges for each alloy. The tensile test of the investigated copper alloys were realized in the temperature range of 20÷800 °C with strain rate of 1.2•10-3s–1 on the universal testing machine. Metallographic observations of the structure were carried out on a light microscope and the fractographic investigation of fracture on an electron scanning microscope. Performed experimental studies have proven that analyzed structural factors, in a range of investigated strain conditions at elevated temperature, significantly influence the phenomenon of the Portevin Le Chatelier (PLC) type instability of plastic strain, revealed in low-alloy copper alloys. Moreover, it was found that the impact of examined factors on the PLC effect should be considered comprehensively, taking into account their synergic interactions.
Solidification Characteristics of Mg-Li-Al Alloys
Authors: Król Mariusz
Published: June 2018

The six Mg-Li and Mg-Li-Al alloys in as-cast state namely Mg-4.5%Li, Mg-9%Li, Mg-12%Li, Mg-4.5%Li-1.5%Al, Mg-9%Li-1.5%Al and Mg-12%Li-1.5%Al were prepared and analysed. These alloys have been subjected to the thermal analysis (thermal derivative-analysis and dilatometry study), and the subsequent thermal assessment, mechanical properties and microstructures were studied. The heating and cooling dilatometric curves characterise by a linear reduction (alloys with 12wt.% of Li) and linear increase (alloys with 4.5wt.% of Li) in coefficient of linear thermal expansion as a function of temperature. No transitions in the solid state occur. Based on results of thermal derivative analysis a crystallisation process of Mg-Li and Mg-Li-Al alloys was proposed. Addition of aluminium in ultra-light Mg-Li alloys shows considerably improved strengthening without a reduction in grain size. Increasing the lithium content causes in an increase of hardness.
Characterization of Microstructure and Mechanical Properties of 6060 Aluminum Alloy Processed by ECAP
Authors: Karoń Monika , Adamiak Marcin
Published: June 2018

The purpose of this paper is to present the microstructure and mechanical behavior of 6060 aluminum alloy after intense plastic deformation. Equal Channel Angular Pressing (ECAP) was used as a method of severe plastic deformation. Before ECAP part of the samples were heat treated to remove internal stresses in the commercially available aluminium alloy. The evolution of microstructure and tensile strength were tested after 1, 3, 6 and 9 ECAP passes in annealed and non annealed states. It was found that intensely plastically deformed refined grains were present in the tested samples and exhibited increased mechanical properties. Differences were noted between samples without and after heat treatment
Spread of the ragweed leaf beetle, Ophraella communa LeSage, 1986 (Coleoptera Chrysomelidae), in Piedmont Region (northwestern Italy)
Authors: Bosio Giovanni , Massobrio Viola , Chersi Catarina , Scavarda Giovanni , Clark Shawn
Published: June 2018

Common ragweed, Ambrosia artemisiifolia L., one of the most dangerous invasive species for its high allergenic pollen production, has been spreading in Europe since the 19th century but has not until now recruited any effective natural enemy. In its native range, North america, many insects and fungi are recorded feeding or developing on this weed, reducing common ragweed impact on human health and habitats. Some of these organisms, specific or oligophagous on A. artemisiifolia, are considered promising agents for the biological control of this weed, and in some cases they have already been introduced in other continents. Among these species, the leaf beetle Ophraella communa LeSage (Coleoptera: Chrysomelidae) was found at the beginning of august 2013 attacking common ragweed near a nursery in Galliate (Novara province - piedmont Region). Field surveys were carried out from august to November in various piedmont counties to document the spread of this recently introduced galerucine species. Data are reported regarding the leaf beetle’s morphology, biological cycle, spread, hosts and natural enemies in the new range. Prospects for the biological control of common ragweed in Europe are also discussed.
Anew species of Hemerodromia Meigen 1822 from Sierra Leone
Authors: Raffone Gianni
Published: June 2018

AbstractA new species of Hemerodromia Meigen, 1822 from Sierra Leone is described: Hemerodromia curvinervis n. sp. is related to Hemerodromia portia Jones, 1940, from which it differs in having the veins R4+52 and M1 ondulateand converging apically,  M2 sinuous and reaching to coste of wing, hind tibia apically lacking setae and for the shape of male terminalia
Assessment and Management of Sport-Related Concussion Teaching Trends in Athletic Training Programs
Authors: Wallace Jessica , Beidler Erica , Covassin Tracey
Published: June 2018

Context:

Previous research suggests that health care providers, in general, are not adequately trained in sport-related concussion (SRC) recognition and management. However, it is unclear if athletic training educators are instructing athletic training students on evidence-based SRC assessment and management protocols.

Objective:

To examine and identify which SRC resources and management tools are being used to teach and prepare athletic training students to clinically evaluate and manage SRCs.

Design:

Cross-sectional study.

Setting:

Single Web-based survey.

Patients or Other Participants:

One hundred two athletic training educators.

Main Outcome Measure(s):

Survey questions collected education level, years of experience as an athletic trainer, sex, role within the athletic training program, and the type of athletic training program at their institution. Participants were asked which position statement or consensus statement was used to teach SRC and, finally, which SRC management tools were taught to students in regard to SRC evaluation, management, and return to play.

Results:

Respondents have been certified athletic trainers for an average of 17.9 ± 6.5 years and accumulated a mean of 9.9 ± 6.8 years of clinical experience before transitioning into educational roles. Among the respondents to the survey, 99% of educators are using the National Athletic Trainers' Association position statement to teach SRC. The clinical examination (100%) was the most widely taught evaluation tool among respondents. Out of all the respondents, over 80% of educators are teaching clinical use and application of the Sport Concussion Assessment Tool 3, Balance Error Scoring System, and computerized neurocognitive testing; however, only 71% are teaching the stepwise progression, and less than 30% are teaching newer tools documented in SRC literature.

Conclusions:

Educators are following recommended practices of teaching a multifaceted approach to SRC evaluation and management. However, instruction is lacking on the use of a stepwise return-to-play progression and newer SRC management tools that assess vestibular and ocular-motor impairment.
Motivators, Anticipated Challenges, and Supportive Factors for Athletic Trainers Pursuing the Doctor of Athletic Training Degree
Authors: Mulder Evan R. , Bacon Cailee E. Welch , Edler Jessica R. , Hankemeier Dorice A. , Games Kenneth E. , Van Lunen Bonnie L. , Eberman Lindsey E.
Published: June 2018

Context:

The doctor of athletic training degree (DAT) is a new concept in athletic training. Athletic trainers (ATs) currently pursue the degree, but little is known about why they choose the DAT.

Objective:

To explore ATs' motivations to pursue the DAT degree.

Design:

Qualitative study.

Setting:

Individual telephone interviews.

Patients or Other Participants:

Twelve first-semester DAT students (6 males, 6 females; age = 32.2 ± 5.2 years; athletic training experience = 9.1 ± 5.7 years) participated.

Main Outcome Measure(s):

Each individual telephone interview was transcribed verbatim and all identifying information was redacted. Two members of the research team used a phenomenological approach to complete data analysis. Constant comparison was used throughout data analysis to ensure consistency among individuals. A third investigator served as an external consultant to verify themes and accuracy of coding. Her review also confirmed discontinuation of interviews upon reaching data saturation. Trustworthiness of the data was established using multiple-analyst triangulation and peer review.

Results:

Four themes emerged affecting DAT student motivations for pursuing the degree: (1) personal motivators, (2) program-specific motivators, (3) initial perceived challenges, and (4) supportive factors. Participants indicated that intrinsic pursuit of lifelong learning, professional advancement, future employment opportunities, improved value within their workplace, and mentors' influence impacted them to pursue a DAT. Participants were motivated to develop professionally and advance knowledge and skills while also selecting programs based on program and faculty reputation and engagement in professional advocacy. While time commitment, work-life balance, cost, and online learning expectations were anticipated challenges, participants perceived that family, employers, peers, organization, and time management were supportive factors that would help them be successful.

Conclusions:

Students are pursing the DAT degree because of both intrinsic and extrinsic motivators. Individual program characteristics also influence the pursuit of the DAT. Students do anticipate challenges but surround themselves with supportive factors to help them be successful.
Curation of a Simulation Experience by the Clinical Scholar: An Educational Technique in Postprofessional Athletic Training
Authors: Winkelmann Zachary K. , Eberman Lindsey E. , Edler Jessica R. , Livingston Laura B. , Games Kenneth E.
Published: June 2018

Context:

Postprofessional athletic training programs continue to prepare advanced-practice leaders in the profession. As part of being leaders and clinical scholars within the field, it is important that students pursing postprofessional graduate education be exposed to curriculum and instructional theory, practice, and strategies.

Objective:

To describe an education technique focused on the curation of a simulation assignment as part of a postprofessional athletic training course as a means to develop an appreciation of instructional strategies as a clinical scholar.

Background:

The postprofessional athletic training student (PP-ATS) may be working as a full-time clinician, graduate assistant, or novice educator, or as an intern within an athletic training clinic. Regardless of employment status, PP-ATSs engage with several key stakeholders, ranging from parents and legal guardians to coaching staff and professional athletic training students. The PP-ATS may be tasked to provide education to these stakeholders in the form of patient participation status to a coach, describing the pathogenesis of a condition to a patient, and rationale for care to professional athletic training students.

Description:

The PP-ATSs were placed in learning communities of 3 to 5 students. The learning communities were tasked with the development of high- and low-fidelity simulations for learners (the other PP-ATSs in the course) to engage in during an intensive and focused learning session, facilitation of the experience, and a debrief encounter.

Clinical Advantage(s):

A 2-fold benefit exists. First, PP-ATSs are engaged in the design and development of a simulation experience as an instructional intervention. Second, simulation learners are gainfully engaged in low-stakes patient encounters that promote professional growth.

Conclusion(s):

Developing and implementing learner-curated simulation experiences exposes PP-ATSs to an innovative instructional strategy in athletic training.
Экстремальные задачи с ограничениями в $H^2$ и формулы Карлемана
Authors: Baratchart Laurent , Leblond Juliette , Seyfert Fabien
Published: June 2018

Рассматривается экстремальная задача наилучшего приближения некоторой функции $f$ из $L^2(I)$, где $I$ является подмножеством окружности, следом функции Харди, модуль которой поточечно ограничен некоторой калибровочной функцией на дополнительном подмножестве.
Библиография: 36 названий.
El procedimiento de modificación de la capacidad en España diez años después de la entrada en vigor de la Convención de la ONU sobre los derechos de las personas con discapacidad
Authors: Botello Pedro
Published: June 2018

Diez años después de la entrada en vigor de la Convención de la ONU sobre los Derechos de las Personas con Discapacidad en España, podemos afirmar dos ideas fundamentales respecto a la adaptación de su artículo 12 a nuestro Ordenamiento: 1º.- El procedimiento de incapacitación sigue estando formado por las mismas figuras antes y después de la Convención. 2º.- El orden de preferencia de las figuras de protección cambió radicalmente, ya que tras la entrada en vigor de la Convención la curatela, casi inexistente hasta entonces, ha pasado a ser la figura preferente y la tutela, que antes de la Convención era la figura principal del procedimiento de incapacitación, se ha convertido en una institución totalmente residual.
Estrogenicity and cytotoxicity of sediments and water from the drinkwater source-basin of Montevideo city, Uruguay
Authors: Griffero Luciana , Gomes Giselle , Berazategui Mauro , Fosalba Claudia , Mello Franco Teixeira de , Rezende Carlos , Bila Daniele , Gacía-Alonso Javier
Published: June 2018

Frequently new pollutants are released into the environment, demanding the employment of generic methods to detect toxic responses. In vitro bioassays such as the yeast estrogenicity screening (YES) allow detecting estrogenic and citotoxic compounds avoiding the employment of invasive methods. We determined the cytotoxicity and estrogenic activity in sediments of the Santa Lucia River Basin (Uruguay) using YES assay and the association with land uses and parameters of water quality and sediment. Water quality parameters confirm the eutrophication process of the Santa Lucía River, which was mainly reflected by high levels of TP and ammonium. High values of estrogenic activity in sediments (E2-EQ 8.49 ng g-1 of sediment) were found mainly in urbanized and cultivated areas. However, estrogenicity and cytotoxicity also was found in sites associated with other land uses such as rangelands. These data provide evidence that Santa Lucía River basin contains a variety of chemicals (including estrogenic and toxic chemicals of unknown and potentially diverse sources) that should be investigated further.YES assay proved to be a useful tool for characterizing estrogenic responses, and due to the human and ecological health importance, we suggest the employment of these kinds of bioassays as tools for environmental monitoring of EDCs substances.
Silver effect on the biodegradation process of styrene-ethylene/butylene-styrene based thermoplastic elastomers compounds upon weathering exposure
Authors: Tomacheski Daiane , Pittol M , Vier S , SimÃµes D.N. , Ribeiro V.F. , Santana R.M.C.
Published: June 2018

The incorporation of antibacterial additives in polymeric materials has become common to reduce the colonization of microorganisms in daily household items. This kind of product can be helpful to prevent diseases, but following the end of its useful lifetime, it might become an environmental problem, causing hazards also to the beneficial soil-borne microbes. This study aims to evaluate the effect of thermoplastic elastomers (TPEs) compounds loaded with silver ions (Ag+_bentonite, Ag+_phosphate) and nanoparticles (AgNp_silica) in the soil microbiota. Samples were exposed to weathering for 3, 6, 9 and 12 months, and monitored by carbon dioxide (CO2) production in the soil for 4 months. Standard sample exposed to weather by 6, 9 and 12 months showed higher CO2 production than samples unexposed or exposed for 3 months. By contrast, silver-loaded samples had higher CO2 production in samples pre-aged for 3 months, but the values decreased in samples pre-aged for 6, 9 and 12 months. Moreover, soil microbial counts were lower in samples that had lower CO2 production. Though the amount of silver in the soil has been lower than the limit of detection, after intense exposure to weather, the degradation of the polymer may have facilitated the release of silver from the TPE matrix, and on these terms, silver may have caused a harmful effect on soil fungi and bacterial population.
Sediment quality assessment of the tributaries of the Santos-São Vicente Estuarine System – Brazil
Authors: Perina Fernando Cesar , Torres Ronaldo José , Mozeto Antonio Aparecido , Nascimento Marcos Roberto Lopes , Abessa Denis Moledo de Souza
Published: June 2018

The Santos-São Vicente Estuarine System has a long history of environmental impacts, and several studies have been performed in this region. However, the quality of its tributaries was not previously studied. This study aimed to investigate the quality of sediments from five rivers (Santana, Mariana, Piaçabuçu, Quilombo, and Diana Rivers) and three sampling sites at Piaçaguera Canal (riverbed, right and left banks), by using an integrated approach involving chemical analyses and whole sediment toxicity tests. Chronic and acute toxicity tests were performed using, respectively, copepods Nitocra sp. and amphipods Tiburonella viscana. The studied sediments presented moderate to high levels of PAHs, PCBs, metals (Cu, Hg, Ni, Pb, Zn), and As. The majority of sediments produced chronic toxic effects, and samples from Piaçaguera Canal were consistently toxic in all acute and chronic tests. The integration of data through multivariate analyses indicated that the toxicity was closely related to the sediments contamination. Chemical data were compared with sediment quality guidelines, which evidenced that the site-specific values are adequate to predict impacts. The levels of organic chemicals and metals suggest constant inputs from diffuse and point sources, demanding actions to ensure effective control and management of the contamination sources to the estuary.
A simple method for evaluation of the total concentration of Cd, Cr, Cu, Pb and Zn in sediments from the São Gonçalo channel in Pelotas, RS, Brazil
Authors: Timm Janaina Garcia , Parodes Pinto Ane Martiele Taborda , Alves Marcelo Moller , Clasen Caroline Dutra , Sanches Filho Pedro José , Ribeiro Anderson Schwingel , Vieira Mariana Antunes
Published: June 2018

This study evaluated the total concentrations of Cd, Cr, Cu, Pb and Zn in sediments samples from the São Gonçalo channel, Patos-Mirim lagoon complex, RS state, Southern Brazil during 2013 autumn, winter and spring, and 2014 summer. Ultrasound-assisted extraction method was employed to extract metals from the sediment samples. The sample powder was mixed with HNO3 and HF in an ultrasonic bath during 60 minutes at 25 oC. The limits of detection were 0.002; 0.026; 0.83; 0.386 and 0.44 mg kg-1 for Cd, Cr, Cu, Pb and Zn, respectively. The accuracy of the method was confirmed by analysis of two sediment certified reference materials and its precision was determined by the values of relative standard deviation lower than 9.1%. The concentrations obtained ranged from 0.11 to 0.58 mg kg-1 for Cd; 14.7 to 38.4 mg kg-1 for Cr; 3.9 to 102.0 mg kg-1 for Cu; 1.6 to 3.11 mg kg-1 for Pb; and 29.3 to 126 mg kg-1 for Zn. These values did not exceed the probable effect levels (PEL). Simplicity, low cost and high efficiency are some of the qualities of the method, making it adequate for routine analysis.
Metals, trace elements and ecotoxicity in sediments of the Cubatão River, Brazil
Authors: Borrely Sueli Ivone , Garcia Vanessa Silva Granadeiro , Borrely Thales , Fávaro Deborah Inês Teixeira
Published: June 2018

The Cubatão River is one of the most important waterways of the coast of São Paulo. The continuous discharge of domestic and industrial effluents into the river and its tributaries resulted in loss of water quality across the system. Industrial and domestic landfills are also located around the studied area. The purpose of this study was to assess two aspects of sediments from the river and two of its tributaries (Perequê and Pilões Rivers): presence of trace elements and toxic metals, and ecotoxicity. Four sampling surveys were conducted from 2010 to 2011 on six different sites (here named P0, P2, P4, P5, P7 and P8). Ecotoxicity was assessed by exposing Hyalella azteca to the collected sediments. Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectrometry (GF AAS and CV AAS) techniques were applied for measuring concentration of metals and trace elements. The latter enabled quantification of Cd, Pb and Hg, while the former enabled quantification of a wide range of metals and trace elements. As, Cr and Zn concentrations obtained by INAA as well as AAS results were compared to threshold effect levels (TEL) and probable effect levels (PEL), the sediment quality guidelines proposed by the Canadian Council of Ministers of the Environment (CCME) for evaluating the potential effects on aquatic organisms. Cd and Hg values did not exceed TEL at the most of samples. Pb exceeded TEL at only one site campaign. As, Cr and Zn values exceeded TEL in most of sampling sites, with P2 and P4 showing the highest concentrations.
Influence of solution treatment on microstructure and stress rupture properties of K439 nickel-base superalloy
Authors: Xu Jin , Zhang Mingjun , Tang Xin , Yang Guangyu , Chen Jingyang , Li Qing , Xiao Chengbo
Published: June 2018

The isochronal solution treatment (4h) in the 1080-1190°C range with air cooling are performed to investigate the effects of solution temperature on the microstructure and stress rupture properties of K439 alloy. The detailed as-cast and solution treated microstructures were analyzed through optical microscopy (OM), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC). The experimental results show that the as-cast alloy exhibited a typical dendritic structure with five phases of γ, γ´, γ/γ´, η and MC. After solution heat treated at 1080°C, although all of the γ´ particles in the dendritic cores were dissolved, there were still some of these precipitates in the interdendritic regions beside η phase. With the solution temperature increasing to 1150°C, all of the γ´ and η solutioned and a uniform microstructure was observed. Furthermore, increasing the temperature to 1210°C, a small amount of incipient melting occurred in the alloy. The stress rupture life of K439 alloy at 760°C/530MPa increased with the rising of solution temperature and reached to the top value under the solution temperature of 1150°C. The optimum solution treatment considered to be 1150 C/4 h followed by air cooling.
The Importance of Blowing Snow to Antarctic Aerosols: Number Distribution and more than Source-Dependent Composition – results from the 2ODIAC campaign
Authors: Giordano Michael R. , Kalnajs Lars E. , Goetz J. Douglas , Avery Anita M. , Katz Erin , May Nathaniel W. , Leemon Anna , Mattson Claire , Pratt Kerri A. , DeCarlo Peter F.
Published: June 2018

Abstract. A fundamental understanding of the processes that control Antarctic aerosols is necessary in determining the aerosol impacts on climate-relevant processes from Antarctic ice cores to clouds. The first in situ observational online composition measurements by an aerosol mass spectrometer (AMS) of Antarctic aerosols were only recently performed during the 2-Season Ozone Depletion and Interaction with Aerosols Campaign (2ODIAC) field campaign. 2ODIAC was deployed to sea ice on the Ross Sea near McMurdo Station over two field seasons: Austral spring-summer 2014 and winter-spring 2015. The results presented here focus on the overall trends in aerosol composition primarily as functions of air masses and local meteorological conditions. The results suggest that air mass back trajectories have little impact on either the absolute or relative concentrations of the aerosol constituents measured by (and inferred from) an AMS at a coastal location. However, when the data is parsed by wind speed, two observations become clear. First, a critical wind speed is required to loft snow from the surface, which, in turn, increases particle counts in all measured size bins. Second, this lofted (blowing) snow significantly increases both aerosol chloride and sodium. Further inspection of the AMS data shows that the increased chloride concentrations have distinctive signatures that differ from chloride measured at low wind speed. Also presented are the Cl:Na ratios of snow samples, aerosol filter samples, and non-chloride aerosol constituents measured by the AMS. Additionally, submicron aerosol iodine and bromine concentrations as functions of wind speed are also presented. The results presented here suggest that aerosol composition in coastal Antarctica is a strong function of wind speed and that the mechanisms determining aerosol composition are likely linked to blowing snow.
Temporal variations of the hygroscopicity and mixing state of black carbon aerosols in a polluted megacity area
Authors: Li Kangning , Ye Xingnan , Pang Hongwei , Lu Xiaohui , Chen Hong , Wang Xiaofei , Yang Xin , Chen Jianmin , Chen Yingjun
Published: June 2018

Abstract. Black carbon (BC) aerosols in the atmosphere strongly affect radiative forcing. They are mainly removed from the air by wet deposition, and their lifetime is controlled by their water uptake ability or hygroscopicity, which is a function of the aerosol mixing states. It is well known that atmospheric aging processes coat various materials on BC aerosols and affect their mixing states and hygroscopicity. However, detailed relations between the aging processes, the hygroscopicity and mixing state of BC aerosol particles in polluted city areas are not well understood. Here, we studied the temporal variation of the hygroscopicity and its correlation with the mixing state of ambient BC particles during 2017 summer in Shanghai, China using a hygroscopicity tandem differential mobility analyzer in-line with a single particle soot photometer (HTDMA-SP2 system) as well as a single particle aerosol mass spectrometer (SPAMS). BC particles with 120 nm, 240 nm and 360 nm dry diameter were humidified at RH = 85 %. After humidification, particles with growth factors (GFs) of 1.0, 1.2 and 1.4, representing the BC particles with different hygroscopicities (hydrophobic, transition and hydrophilic modes, respectively), were analyzed by a SP2 to obtain their BC mixing states. The diurnal trends of coating thickness and chemical mixing state show that coating materials of BC particles were distinct between daytime and nighttime. The differences were associated with the hygroscopicity of BC particles. Single particle mass spectrometry and other chemical characterization techniques revealed that during nighttime with lower temperature and higher relative humidity (RH), formation or condensation of nitrates resulted in an enhanced hygroscopicity of BC particles. During daytime, secondary organic carbon formation was mainly responsible for the change of hygroscopicity of BC particles. Due to the high hygroscopicity of inorganic nitrate, a thinner nitrate coating on BC particles could convert fresh BC particles to aged hygroscopic ones during nighttime while a thicker coating layer of secondary materials was required to reach the same overall hygroscopicity during daytime since the participation of secondary organic carbon. Different atmospheric aging processes between daytime and nighttime led to the change of BC particles' mixing states, which play a fundamental role in determining their hygroscopicity. To our knowledge, this is the first report of links between temporal variations of the hygroscopic growth of BC particles and atmospheric aging processes in polluted environment. These findings have significant ramification of understanding the aging process, wet removal as well as climate effects of BC particles.
Bias correction of multi-ensemble simulations from the HAPPI model intercomparison project
Authors: Saeed Fahad , Bethke Ingo , Lange Stefan , Lierhammer Ludwig , Shiogama Hideo , Stone Dáithí A. , Trautmann Tim , Schleussner Carl-Friedrich
Published: June 2018

Abstract. Prior to using climate data as input for sectoral impact models, statistical bias correction is commonly applied to correct climate model data for systematic deviations. Different approaches have been adopted for this purpose, however the most common are those based on the transfer functions, generated to map the distribution of the simulated historical data to that of the observations. Here, we present results of a novel bias correction method, developed for Inter-Sectoral Impact Model Intercomparison Project Phase 2b (ISIMIP2b) and applied to outputs of different GCMs generated within the HAPPI (Half A degree Additional warming, Projections, Prognosis and Impacts) project. We have employed various analysis measures including mean seasonal differences, ensemble variability, annual cycles, extreme indices as well as a global hydrological model to assess the performance of ISIMIP2b bias correction technique. The results indicate substantial improvements after the application of bias correction when compared against observational data. Moreover, the extreme indices as well as output of global hydrological model also reveal a marked improvement. At the same time, the ensemble spread of the original data is preserved after the application of bias correction. We find that the bias corrected HAPPI data can provide a reliable basis for sectoral climate impact projections.
A protocol for an intercomparison of biodiversity and ecosystem
services models using harmonized land-use and climate scenarios
Authors: Kim HyeJin , Rosa Isabel M. D. , Alkemade Rob , Leadley Paul , Hurtt George , Popp Alexander , van Vuuren Detlef P , Anthoni Peter , Arneth Almut , Baisero Daniele , Caton Emma , Chaplin-Kramer Rebecca , Chini Louise , De Palma Adriana , Di Fulvio Fulvio , Di Marco Moreno , Espinoza Felipe , Ferrier Simon , Fujimori Shinichiro , Gonzalez Ricardo E. , Gueguen Maya , Guerra Carlos , Harfoot Mike , Harwood Thomas D. , Hasegawa Tomoko , Haverd Vanessa , Havlík Petr , Hellweg Stefanie , Hill Samantha L. L. , Hirata Akiko , Hoskins Andrew J. , Janse Jan H. , Jetz Walter , Johnson Justin A. , Krause Andreas , Leclère David , Martins Ines S. , Matsui Tetsuya , Merow Cory , Obersteiner Michael , Ohashi Haruka , Poulter Benjamin , Purvis Andy , Quesada Benjamin , Rondinini Carlo , Schipper Aafke , Sharp Richard , Takahashi Kiyoshi , Thuiller Wilfried , Titeux Nicolas , Visconti Piero , Ware Christopher , Wolf Florian , Pereira Henrique M.
Published: June 2018

Abstract. To support the assessments of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the IPBES Expert Group on Scenarios and Models is carrying out an intercomparison of biodiversity and ecosystem services models using harmonized scenarios (BES-SIM). The goals of BES-SIM are (1) to project the global impacts of land use and climate change on biodiversity and ecosystem services (i.e. nature’s contributions to people) over the coming decades, compared to the 20th century, using a set of common metrics at multiple scales, and (2) to identify model uncertainties and research gaps through the comparisons of projected biodiversity and ecosystem services across models. BES-SIM uses three scenarios combining specific Shared Socio-economic Pathways (SSPs) and Representative Concentration Pathways (RCPs) to explore a wide range of land-use change and climate change futures. This paper describes the rationale for scenarios selection, the process of harmonizing input data for land use, based on the second phase of the Land Use Harmonization Project (LUH2), and climate, the biodiversity and ecosystem service models used, the core simulations carried out, the harmonization of the model output metrics, and the treatment of uncertainty. The results of this collaborative modelling project will support the ongoing global assessment of IPBES, strengthen ties between IPBES and the Intergovernmental Panel on Climate Change (IPCC) scenarios and modelling processes, advise the Convention on Biological Diversity (CBD) on its development of a post-2020 strategic plans and conservation goals, and inform the development of a new generation of nature-centred scenarios.
The TropD software package: Standardized methods for calculating
Tropical Width Diagnostics
Authors: Adam Ori , Grise Kevin M. , Staten Paul , Simpson Isla R. , Davis Sean M. , Davis Nicholas A. , Waugh Darryn W. , Birner Thomas
Published: June 2018

Abstract. Observational and modeling studies suggest that Earth's tropical belt has widened over the late 20th century and will continue to widen throughout the 21st century. Yet estimates of tropical width variations differ significantly across studies. This uncertainty, to an unknown degree, is partly due to the large variety of methods used in studies of the tropical width. Here, methods for eight commonly-used metrics of the tropical width are implemented in a Tropical-width Diagnostics code package (TropD) in the MATLAB programming language. To consolidate the various methods, the operations used in each of the implemented methods are reduced to two basic calculations: finding the latitude of a zero crossing, and finding the latitude of a maximum. A detailed description of the methods implemented in the code and of the code syntax is provided, followed by a method sensitivity analysis for each of the metrics. The analysis provides information on how to reduce the methodological component of the uncertainty associated with fundamental aspects of the calculations, such as monthly vs. seasonal averaging biases, grid dependence, sensitivity to noise, and sensitivity to threshold criteria.
Conservative finite-volume forms of the Saint-Venant equations for
hydrology and urban drainage
Authors: Hodges Ben R.
Published: June 2018

Abstract. New finite-volume forms of the Saint-Venant equations for one-dimensional (1D) open-channel flow are derived. The new equations are in the flux-gradient conservation form and serve to transfer portions of both the hydrostatic pressure force and the gravitational force from the source term to the conservative flux term. The derivation introduces an analytical approximation of the free surface across a finite volume element (e.g. linear, parabolic) as well as an analytical approximation of the bottom topography. Integration of the product of these provides an approximation of a piezometric pressure gradient term that can be split between the source and the conservative flux terms without introducing new variables within the discretization. The resulting finite-volume equations are written entirely in terms of flow rates, cross-sectional areas, water surface elevations, and the channel bottom elevation (but without using any volume-averaged bottom slope). The new conservative form should be more tractable for large-scale simulations of river networks and urban drainage systems than the traditional conservative form of the Saint-Venant equations where it is difficult to maintain a well-balanced discretization for highly-variable topography.