scholarly journals Modelling the Leachability of Strontium and Barium from Stone Building Materials

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3403
Author(s):  
Agnieszka Pękala ◽  
Michał Musiał
Keyword(s):  
Trace Elements ◽  
Building Materials ◽  
Research Work ◽  
Porous Silica ◽  
Basic Research ◽  
Human Beings ◽  
Stone Material ◽  
Geochemical Analyses ◽  
Geochemical Studies ◽  
The Impact

In order that the impact on the environment and human beings can be assessed, it may prove necessary for geochemical research work to entail determinations of concentrations of trace elements in building materials, and it is also likely that this will be a time-consuming and financially-demanding business. Additionally, once basic research has been carried out to determine the mineral composition and structural and textural features, it will then be important to determine concentrations of elements that affect the surrounding natural environment and the health of human beings. This paper thus describes mineralogical and geochemical analyses performed on the stone material that opoka rocks represent. Mineralogical studies have shown that the studied opoka rocks most often have cryptocrystalline silica dispersed among carbonate components. The texture of the rock is slightly porous. Silica in the form of type opal A and CT (cristobalite–tridymite) is the main mineral component of the opoka rocks. Carbonate minerals represented by calcite were an important component in the opoka rocks. Earlier geochemical studies focused on the concentration of Sr and Ba. However, the determination of the leachability of these elements as a function of time is a novelty in this study. Trace elements leached from the material matrix were made subject to determinations. The MATLAB program was used to assess leachability in the cases of both strontium and barium, by reference to the Mamdani–Assilian fuzzy algorithm. The presented work has thus sought to experiment with the use of statistical methods to monitor the effectiveness of geochemical processes taking place over time.

scholarly journals Geochemistry of marine and lacustrine bands in the Upper Carboniferous of the Netherlands

2008 ◽  
Vol 87 (4) ◽  
pp. 309-322 ◽  
Author(s):  
H. Kombrink ◽  
B.J.H. van Os ◽  
C.J. van der Zwan ◽  
Th.E. Wong
Keyword(s):  
Trace Elements ◽  
Organic Carbon ◽  
The Netherlands ◽  
Gamma Ray ◽  
Dilution Effect ◽  
Major And Trace Elements ◽  
Upper Carboniferous ◽  
Geochemical Analyses ◽  
Geochemical Studies ◽  
Selection Of

AbstractGeochemical studies on Upper Carboniferous marine bands showed that marked enrichment in redox-sensitive trace elements (uranium (U), vanadium (V), molybdenum (Mo)) mostly occur if they containGoniatites. Goniatitesindicate deposition in relatively distal and deep marine environments. In contrast, Westphalian marine bands found in the Netherlands predominantly show aLingulafacies, indicating deposition in a nearshore environment. TheseLingulamarine bands are mostly lacking significant trace element enrichments. The aim of this paper is to explain the mechanisms causing the differences in geochemical characteristics between distal (Goniatitesfacies) and proximal (Lingulafacies) marine bands. Geochemical analyses (total organic carbon (TOC), sulfur (S), major and trace elements) were carried out on a selection of these marine bands. Furthermore, a comparison was made with some lacustrine bands which broadly show the same sedimentary development as theLingulamarine bands. The results show that theLingulamarine bands, in contrast to theGoniatitesand lacustrine bands, are characterised by low organic carbon contents (1 – 2 wt.%). A relatively high input of siliciclastics probably prevented the accumulation of organic-rich layers (dilution effect). In turn, low organic carbon contents most likely prevented the effective scavenging of trace elements. Although the lacustrine bands are characterised by high TOC contents, here the limited availability of trace elements in fresh water forms the best explanation for low trace metal enrichments. Since marine bands form stratigraphically important horizons in the Upper Carboniferous, many attempts have been made to recognise marine bands using well logs (gamma-ray). The results from this study show that using gamma-ray devices (detecting U-enrichments), only marine bands in aGoniatitesfacies are clearly recognised whileLingulamarine bands are not detected.

Influence of Different In-Process and Building Materials with Varying Hardness on Impact Sensitivity of the Matchhead Composition

2019 ◽  
Vol 969 ◽  
pp. 41-47
Author(s):  
S.P. Sivapirakasam ◽  
K. Harisivasri Phanindra ◽  
Mahadevan Surianarayanan ◽  
K.R. Balasubramanian
Keyword(s):  
Impact Energy ◽  
Building Materials ◽  
Research Work ◽  
Impact Sensitivity ◽  
Contact Material ◽  
Contact Materials ◽  
Limited Impact ◽  
The Impact ◽  
Process Material

The objective of this research work is to study the influence of different in-process contact materials (steel, aluminium and brass) and building contact materials (concrete and wood), and its hardness on the impact sensitivity of matchhead composition. The BAM fall hammer was used for measurement of impact sensitivity. The result demonstrated that the in-process and building contact materials, and its hardness imparted variation to the sensitivity between 3.33J and 15.892J. The least LIE was found at 3.33J for the steel at 115 HRB and 117 HRB; 3.72J for aluminium at 53 HRB; 4.7J for brass at 82 HRB; 12.16J for concrete at 35 RHN, and 13.14J for wood at 16 HRB. The limited impact energy was lowest when there was contact between steel and steel as in-process material and contact between concrete and concrete as building contact material. The impact sensitivity was higher for material with higher hardness for all building and in-process contact materials. Brass and wood is suggested to be used as process and building materials in order to reduce the risk of explosions due to impact sensitivity.

Bibliometric Analysis on Dengue Virus (Preprint)

2020 ◽  
Author(s):  
Mehwish Arshad ◽  
Malik Muhammad Saad Missen ◽  
Ali Mustapha Qamar ◽  
Mujtaba Husnain ◽  
Gyu Sang Choi
Keyword(s):  
Dengue Virus ◽  
Southeast Asia ◽  
Bibliometric Analysis ◽  
Research Work ◽  
Disease Spread ◽  
Digital Object Identifier ◽  
Original Research ◽  
Human Beings ◽  
Virus Research ◽  
The Impact

BACKGROUND Dengue is an acute pyretic disease spread by the mosquito-borne dengue virus. It is a self-limiting illness, characterized by fever, myalgia, headache, and rash, and its severe forms are hemorrhagic fever and shock syndrome may lead to multisystem participation and death. The dengue was originated in animals specifically in the monkeys that further overturned into human beings about 500 years ago. Initially, this virus was observed in the subcontinents of Africa and Southeast Asia in mid of 20th century. The dengue viruses in viremic individuals and the Aedes aegypti mosquito (yellow fever mosquito) were the main factors involved in spreading this virus throughout tropical Southeast Asia via maritime shipments. A number of experiments were performed in the last two decades for the remedy of this disease that needs to be arranged in some manageable form for extracting research-oriented information. OBJECTIVE The bibliometric analysis is one of the popular approaches to analyzing the literature review that helps in the mapping of research and development (R&D) activities. We implement this analysis model in illustrating and quantifying the scientific scenario related to dengue research worldwide. While performing the bibliometric analysis we can produce scalable results from an individual to an international level by depicting the collaboration of each author, the role of the impact factor of highly active journals, etc. METHODS In order to perform the above-mentioned task, the Web of Science (WoS) and Scopus databases were selected as the repository of the noteworthy research work done in various tasks related to the dengue virus. In total, 18607 publications were considered within the period 1872-2019. Among these, a total of 9664 and 30604 documents were retrieved from WoS and Scopus databases respectively. After merging the data and eliminating the duplicates, the total number of publications was 32150. Furthermore, on the basis of the titles and abstracts, a total of 18607 studies were retrieved related to dengue virus research excluding the studies related to other diseases and viruses. The retrieved documents include articles, books, conference papers, data papers, editorials, erratum, letters, meeting abstracts, news items, notes, proceeding papers, reprint, review, and short survey papers. The metadata of the retrieved publications contains the information including the date of publication, authors, affiliation, digital object identifier (DOI), the title, abstract, name of the journal, and keywords, among other key aspects that were managed in Excel. For visualization and analysis purposes, state-of-art tools like Mendeley, Microsoft Excel, Biblioshiny, and VOS-viewer (version 1.6.15) were used. RESULTS After performing a careful analysis of the retrieved 18607 publications, it was observed that about 79.00% (14625) of the total articles were the original research papers, 5.99% (1115) were review and survey articles, 4.72% (878) were the editorial letters and remaining 3.41% (635) were the conference proceedings. Furthermore, it was also witnessed that 90.57% (16844) of the collected research articles were published in English and the remaining 9.47% (1763) are published in other languages. Among the journals that published these articles, the international journal “American Journal of Tropical Medicine and Hygiene” stood first having the highest number of papers (698) published in this journal. The research group of academic institutes of Mahidol University, University of Malaya, and the National University of Singapore contributed more than the other universities. The average citation of the top 15 articles was found to be 1,213. The paper having the title “The Global Distribution and Burden of Dengue” was the most cited (3833) as compared with other papers. The network visualization maps conclude that the most frequent terms that appeared in the papers were dengue, dengue virus, antibodies, female, aedes, mosquito, virus replication, epidemic, dengue vaccine. CONCLUSIONS The bibliometric analysis concluded that there is a strong bonding between the authors and institutions for instance Mr. HARRIS E from The University of California, USA is found to be the most productive author with 158 published articles. In general, this study not only demonstrates a full understanding of global dengue virus research but also can contribute to forthcoming further research in this field.

scholarly journals Thermal behavior of light earth used for building insulation: Insight on PCM introduction impact

2021 ◽  
Vol 2069 (1) ◽  
pp. 012120
Author(s):  
Farjallah Alassaad ◽  
Karim Touati ◽  
Daniel Levacher ◽  
Nassim Sebaibi
Keyword(s):  
Thermal Properties ◽  
Building Materials ◽  
Phase Change Materials ◽  
Natural Fiber ◽  
Research Work ◽  
Thermal Inertia ◽  
Thermal Response ◽  
Thermal Insulating ◽  
High Thermal Inertia ◽  
The Impact

Abstract To reduce building significant contribution to greenhouse gas emissions, architects and engineers are seeking eco-friendly construction solutions. Among investigated options, building’s thermal insulation and heat storage can be cited. In this regard, earth-based materials are attracting particular interest. These last years, there is a renewed interest in these eco-friendly building materials and techniques. This is due to many advantages that they present: excellent humidity regulation ability and high thermal inertia. Present study aims to improve light earth thermal properties. Specifically, this research work focuses on the development of an insulating and heat storing material. To achieve this, phase change materials (PCM) are incorporated in soil-natural fiber mixtures. In fact, different light earth samples are first prepared. Then, thermally characterized to highlight the impact of PCM on the light earth thermal insulating, heat storing properties and thermal response to changing boundary conditions. The incorporation of PCM showed an interesting improvement of the light earth thermal properties namely on thermal conductivity, specific heat capacity, and thermal comfort time.

scholarly journals The Development of Freshwater Deltas and their Environmental and Economic Significance / Rozwój I Znaczenie Środowiskowo-Użytkowe Delt W Zbiornikach Śródlądowych

2015 ◽  
Vol 22 (1) ◽  
pp. 107-123
Author(s):  
Martyna A. Rzętała ◽  
Andrzej Jaguś ◽  
Robert Machowski ◽  
Mariusz Rzętała
Keyword(s):  
Trace Elements ◽  
Chemical Composition ◽  
Research Work ◽  
Basic Research ◽  
Common Reed ◽  
Water Bodies ◽  
Geochemical Background ◽  
Fine Coal ◽  
Economic Significance ◽  
Delta Sediments

Abstract The article presents the results of studies concerning the delta forms that arise as a result of the sedimentation of the debris fed to water bodies by watercourses. The study covered several dozen anthropogenic water bodies in the Upper Silesia region, which is well known for its high degree of urbanisation and industrialisation. Basic research work included morphometric measurements of deltas, analyses of the mechanical and chemical composition of delta sediments and analyses of the chemical composition of the common reed growing on the deltas. The research has demonstrated that the deltas exhibit certain characteristics typical of anthropogenic forms that result from the pollutants found in watercourses. In delta sediments, grains of sand usually dominate, but in many cases the share of the < 0.02 mm fraction is as high as ca. 30%. Sediments often contain fine coal and other organic pollutants, which is reflected by high weight loss on ignition. The content of trace elements in delta sediments is usually many times higher than the geochemical background for all types of sedimentary rocks. Deltas are an environment where pollutants accumulate and some of them are assimilated by plants. The content of macro elements in common reed tissues from different deltas does not vary widely while the content of trace elements often results from their content in the sediments. The material that forms deltas can be extracted and in some cases even used as fuel

Piezoelectric β-polymorph formation of new textiles by surface modification with coating process based on interfacial interaction on the conformational variation of poly (vinylidene fluoride) (PVDF) chains

2020 ◽  
Vol 91 (3) ◽  
pp. 31301
Author(s):  
Nabil Chakhchaoui ◽  
Rida Farhan ◽  
Meriem Boutaldat ◽  
Marwane Rouway ◽  
Adil Eddiai ◽  
...  
Keyword(s):  
High Efficiency ◽  
Vinylidene Fluoride ◽  
Research Work ◽  
Research Area ◽  
Interfacial Interaction ◽  
Tetraethyl Orthosilicate ◽  
Poly Vinylidene Fluoride ◽  
Carbon Nanofillers ◽  
The Impact ◽  
Advanced Applications

Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β-phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2CH3)4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β-phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β-phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β-phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β-phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.

Microstructural and Mechanical Behaviour Evaluation of Mg-Al-Zn Alloy Friction Stir Welded Joint

2020 ◽  
Vol 17 (3) ◽  
pp. 8150-8159
Author(s):  
Kulwant Singh ◽  
Gurbhinder Singh ◽  
Harmeet Singh
Keyword(s):  
Heat Treatment ◽  
Friction Stir Welding ◽  
Magnesium Alloys ◽  
Mechanical Performance ◽  
Fuel Efficiency ◽  
Research Work ◽  
Grain Structure ◽  
Tensile Fracture ◽  
Friction Stir ◽  
The Impact

The weight reduction concept is most effective to reduce the emissions of greenhouse gases from vehicles, which also improves fuel efficiency. Amongst lightweight materials, magnesium alloys are attractive to the automotive sector as a structural material. Welding feasibility of magnesium alloys acts as an influential role in its usage for lightweight prospects. Friction stir welding (FSW) is an appropriate technique as compared to other welding techniques to join magnesium alloys. Field of friction stir welding is emerging in the current scenario. The friction stir welding technique has been selected to weld AZ91 magnesium alloys in the current research work. The microstructure and mechanical characteristics of the produced FSW butt joints have been investigated. Further, the influence of post welding heat treatment (at 260 °C for 1 h) on these properties has also been examined. Post welding heat treatment (PWHT) resulted in the improvement of the grain structure of weld zones which affected the mechanical performance of the joints. After heat treatment, the tensile strength and elongation of the joint increased by 12.6 % and 31.9 % respectively. It is proven that after PWHT, the microhardness of the stir zone reduced and a comparatively smoothened microhardness profile of the FSW joint obtained. No considerable variation in the location of the tensile fracture was witnessed after PWHT. The results show that the impact toughness of the weld joints further decreases after post welding heat treatment.

Impacto de la comunicación de la responsabilidad social universitaria en la selección de universidad y efecto mediador de la reputación

2020 ◽  
Author(s):  
Lucy Erazo-Coronado ◽  
Sergio Llano-Arristizábal ◽  
Miguel Garcés-Prettel ◽  
Ana-María Erazo-Coronado
Keyword(s):  
Social Responsibility ◽  
Professional Training ◽  
Research Work ◽  
Community Support ◽  
Human Beings ◽  
Cross Sectional ◽  
Public And Private ◽  
University Selection ◽  
Cross Sectional Design ◽  
Institutional Websites

The emerging concept of university social responsibility (USR) consists in the fulfillment of the mission of the university in terms of ethical standards, community support, respect for human beings, and respect for the environment. Thus, universities must not only provide professional training but also instill ethical principles in students to allow them to behave as good citizens and help solve community problems. On the other hand, competition for students requires efficient management of university reputation and communication with their stakeholders, to demonstrate the accomplishment of the university’s mission and attract potential students. The objective of this paper is thus to explain the causal relationship between communication about university social responsibility (USR) activities through institutional websites and university selection, as well as the role of reputation. Research work was carried out based on an explanatory cross-sectional design, with a sample of 356 subjects from a population of 11th-grade students from public and private schools in the City of Barranquilla (Colombia). The results revealed that USR communication through institutional websites has a significant influence on university selection, not only directly but also indirectly, through reputation as a mediating variable. These findings contribute at a theoretical level by providing empirical evidence to understand and explain the analyzed topic. Furthermore, the results provide useful information to evaluate USR disclosure and implement strategies to make progress on USR issues. Resumen El naciente concepto de responsabilidad social universitaria (RSU) consiste en el cumplimiento de la misión de la universidad dentro de unos estándares éticos, de apoyo a la comunidad, respeto al ser humano y al medio ambiente. Así, pues, la universidad no sólo debe impartir formación profesional, sino inculcar a sus estudiantes principios éticos que les permitan comportarse como buenos ciudadanos y contribuir a la solución de los problemas de la comunidad. Por otra parte, la competencia entre universidades exige una gestión eficiente de su reputación y de la comunicación con sus distintos stakeholders, para demostrar a la sociedad el cumplimiento de su misión social, y para atraer estudiantes potenciales hacia la institución. Por lo tanto, este artículo tiene como objetivo explicar la relación de causalidad entre la comunicación de las prácticas de RSU en los sitios web institucionales y la selección de universidad, y el papel mediador de la reputación en esta relación. Para lograrlo, se llevó a cabo una investigación cuantitativa de nivel explicativo experimental y diseño transversal, con una muestra conformada por 356 sujetos, de una población de estudiantes de grado 11º de colegios públicos y privados de la ciudad de Barranquilla (Colombia). Los resultados revelan que la comunicación de las prácticas de RSU en los sitios web institucionales ejerce una influencia significativa directa en la intención de selección de universidad, e indirecta, a través de la reputación como variable mediadora. La evidencia empírica aportada representa un avance teórico en la comprensión y explicación del fenómeno estudiado, e igualmente servirá para que las universidades evalúen si están comunicando adecuadamente su responsabilidad social y adopten estrategias para avanzar en este aspecto.

Serving the People in Long Beach, California: Advancing Justice for Southeast Asian Youth through Community University Research Partnerships

2019 ◽  
Vol 16 (1-2) ◽  
pp. 1-34
Author(s):  
R. Varisa Patraporn
Keyword(s):  
Asian American ◽  
Research Work ◽  
Community Based Participatory Research ◽  
Youth Empowerment ◽  
Long Beach ◽  
Structured Interviews ◽  
Research Partnerships ◽  
Community Needs ◽  
The People ◽  
The Impact

Khmer Girl’s in Action is a nonprofit that successfully utilizes community-based participatory research (CBPR) with university partners to create social change for youth in Long Beach, CA. Based on semi-structured interviews and content analysis of news articles, I explore the impact and sustainability of this research work and the research partnerships. Findings highlight impacts such as youth empowerment, heightened awareness around community needs, policy change, and CBPR curriculum improvements in the field as impacts. Sustainability requires integrating research into program funding, utilizing a tailored training curriculum, building on community members prior relationships, and selecting partners that share common goals, levels of commitment, and flexibility. As funders demand more data to justify community needs, understanding more examples of such work in the Asian American community will be useful for informing future partnerships.

Impacto de las tecnologías de la información y las comunicaciones: Una mirada en la Educación Superior

2017 ◽  
Vol 1 (6) ◽  
Author(s):  
Karina Virginia Mero Suárez ◽  
Edwin Joao Merchán Carreño ◽  
Ana Del Rocío Fernández Torres ◽  
Narcisa María Crespo Torres
Keyword(s):  
Higher Education ◽  
Information Technology ◽  
Research Work ◽  
Field Research ◽  
Research Problem ◽  
Research Report ◽  
Educación Superior ◽  
Educational Design ◽  
Educacion Superior ◽  
The Impact

El artículo aborda la necesidad de la creatividad que se impone en la era actual del conocimiento y la importancia que  constituyen las tecnologías como herramientas indispensables en todas las esferas de la vida. En Trabajo toma como campo investigativo los cambios que se llevan a cabo en esta esfera en la Universidad Estatal del Sur de Manabí y la Universidad Técnica de Babahoyo, Ecuador, donde se toman como objeto el proceso de enseñanza aprendizaje en la Educación Superior. El objetivo de la investigación fue comunicar el impacto de las Tecnologías de la Información y las Comunicaciones en las Universidades, donde se hace énfasis en el nuevo rol de los docentes y su nuevo desempeño de facilitadores del aprendizaje en los educandos a través en los nuevos escenarios mediados por las tecnologías. Para el desarrollo exitoso de esta memoria investigativa se   usó como metodología instrumentos que se basaron fundamentalmente en documentos referativos que ayudaron a justificar el problema de investigación, el cual consistía fundamentalmente en el impacto de las nuevos  dispositivos tecnológicos y su utilidad en los centros de altos estudios del país. Se concluyó que las Tecnologías de la Información y Comunicación son herramientas indispensables en la docencia y al mismo tiempo la forma de intervenir en el diseño educativo que nos llevan a explorar nuevos métodos docentes en los escenarios educativos mediados por estas. Se constató además que estas herramientas favorecen satisfactoriamente al proceso si se tiene una buena preparación por parte del docente.   Palabras clave: Herramientas tecnológicas, universidades, formación, docencia universitaria, proceso de enseñanza – aprendizaje Impact of information technology and communications: a look at higher education  Abstract The article states the need of the creativity that prevails in the current era of knowledge and the importance that technologies constitute in all spheres of life. In field research work it takes as changes take place in this area in Southern State University of Manabí and the Technical University of Babahoyo, Ecuador, where they are taken as an object the process of learning in higher education. The aim of the research was to communicate the impact of Information Technology and Communications in the universities, where the emphasis is on the new role of teachers and their new performance of facilitators of learning in students through the new scenarios mediated by technologies. For the successful development of this research report it was used as a methodology instruments based mainly on referative documents that helped to justify the research problem, which consisted mainly of the impact of new technological devices and their use in the centers of higher learning in the country. It was concluded that information technology and communication are indispensable tools in teaching and at the same time how to intervene in the educational design that lead us to explore new teaching methods in educational settings mediated by these. It was further found that these tools successfully promote the process if there is a good preparation by the teacher.

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