Search results for: environmental exposure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8053

Search results for: environmental exposure

1873 Modified Silicates as Dissolved Oxygen Sensors in Water: Structural and Optical Properties

Authors: Andile Mkhohlakali, Tien-Chien Jen, James Tshilongo, Happy Mabowa

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Among different parameters, oxygen is one of the most important analytes of interest, dissolved oxygen (DO) concentration is very crucial and significant for various areas of physical, chemical, and environmental monitoring. Herein we report oxygen-sensitive luminophores -based lanthanum(III) trifluoromethanesulfonate), [La]³⁺ was encapsulated into SiO₂-based xerogel matrix. The nanosensor is composed of organically modified silica nanoparticles, doped with the luminescent oxygen–sensitive lanthanum(III) trifluoromethanesulfonate complex. The precursor materials used for sensing film were triethyl ethoxy silane (TEOS) and (3-Mercaptopropyltriethoxysilane) (MPTMS- TEOS) used for SiO2-baed matrices. Brunauer–Emmett–Teller (BET), and BJH indicate that the SiO₂ transformed from microporous to mesoporous upon the addition of La³⁺ luminophore with increased surface area (SBET). The typical amorphous SiO₂ based xerogels were revealed with X-Ray diffraction (XRD) and Selected Area Electron Diffraction (SAED) analysis. Scanning electron microscope- (SEM) and transmission electron microscope (TEM) showed the porous morphology and reduced particle for SiO₂ and La-SiO₂ xerogels respectively. The existence of elements, siloxane networks, and thermal stability of xerogel was confirmed by energy dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and Thermographic analysis (TGA). UV-Vis spectroscopy and photoluminescence (PL) have been used to characterize the optical properties of xerogels. La-SiO₂ demonstrates promising characteristic features of an active sensing film for dissolved oxygen in the water. Keywords: Sol-gel, ORMOSILs, encapsulation, Luminophores quenching, O₂-sensing

Keywords: sol-gel, ORMOSILs, luminophores quenching, O₂-sensing

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1872 Use of Non-woven Polyethylene Terephthalate Fabrics to Improve Certain Properties of Concrete

Authors: Sifatullah Bahij, Safiullah Omary, Francoise Feugeas, Amanullah Faqiri

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Plastic packages have been broadly used for a long time. Such widespread usage of plastic has resulted in an increased amount of plastic wastes and many environmental impacts. Plastic wastes are one of the most significant types of waste materials because of their non-degradation and low biodegradability. It is why many researchers tried to find a safe and environmentally friendly solution for plastic wastes. In this goal, in the civil engineering industry, many types of plastic wastes have been incorporated, as a partial substitution of aggregates or as additive materials (fibers) in concrete mixtures because of their lengthier lifetime and lower weight. This work aims to study the mechanical properties (compressive, split tensile and flexural strengths) of concrete with a water-cement ratio (w/c) of 0.45 and with the incorporation of non-woven PET plastic sheets. Five configurations -without PET (reference), 1-layer sheet, 2-side, 3-side, and full sample wrapping- were applied. The 7, 14 and 28-days samples’ compressive strengths, flexural strength and split tensile strength were measured. The outcomes of the study show that the compressive strength was improved for the wrapped samples, particularly for the cylindrical specimens. Also, split tensile and flexural behaviors of the wrapped samples improved significantly compared to the reference ones. Moreover, reference samples were damaged into many parts after mechanical testing, while wrapped specimens were taken by the applied configurations and were not divided into many small fragments. Therefore, non-woven fabrics appeared to improve some properties of the concrete.

Keywords: solid waste plastic, non-woven polyethylene terephthalate sheets, mechanical behaviors, crack pattern

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1871 Economic Assessment of CO2-Based Methane, Methanol and Polyoxymethylene Production

Authors: Wieland Hoppe, Nadine Wachter, Stefan Bringezu

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Carbon dioxide (CO2) utilization might be a promising way to substitute fossil raw materials like coal, oil or natural gas as carbon source of chemical production. While first life cycle assessments indicate a positive environmental performance of CO2-based process routes, a commercialization of CO2 is limited by several economic obstacles up to now. We, therefore, analyzed the economic performance of the three CO2-based chemicals methane and methanol as basic chemicals and polyoxymethylene as polymer on a cradle-to-gate basis. Our approach is oriented towards life cycle costing. The focus lies on the cost drivers of CO2-based technologies and options to stimulate a CO2-based economy by changing regulative factors. In this way, we analyze various modes of operation and give an outlook for the potentially cost-effective development in the next decades. Biogas, waste gases of a cement plant, and flue gases of a waste incineration plant are considered as CO2-sources. The energy needed to convert CO2 into hydrocarbons via electrolysis is assumed to be supplied by wind power, which is increasingly available in Germany. Economic data originates from both industrial processes and process simulations. The results indicate that CO2-based production technologies are not competitive with conventional production methods under present conditions. This is mainly due to high electricity generation costs and regulative factors like the German Renewable Energy Act (EEG). While the decrease in production costs of CO2-based chemicals might be limited in the next decades, a modification of relevant regulative factors could potentially promote an earlier commercialization.

Keywords: carbon capture and utilization (CCU), economic assessment, life cycle costing (LCC), power-to-X

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1870 Corrosion Analysis and Interfacial Characterization of Al – Steel Metal Inert Gas Weld - Braze Dissimilar Joints by Micro Area X-Ray Diffraction Technique

Authors: S. S. Sravanthi, Swati Ghosh Acharyya

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Automotive light weighting is of major prominence in the current times due to its contribution in improved fuel economy and reduced environmental pollution. Various arc welding technologies are being employed in the production of automobile components with reduced weight. The present study is of practical importance since it involves preferential substitution of Zinc coated mild steel with a light weight alloy such as 6061 Aluminium by means of Gas Metal Arc Welding (GMAW) – Brazing technique at different processing parameters. However, the fabricated joints have shown the generation of Al – Fe layer at the interfacial regions which was confirmed by the Scanning Electron Microscope and Energy Dispersion Spectroscopy. These Al-Fe compounds not only affect the mechanical strength, but also predominantly deteriorate the corrosion resistance of the joints. Hence, it is essential to understand the phases formed in this layer and their crystal structure. Micro area X - ray diffraction technique has been exclusively used for this study. Moreover, the crevice corrosion analysis at the joint interfaces was done by exposing the joints to 5 wt.% FeCl3 solution at regular time intervals as per ASTM G 48-03. The joints have shown a decreased crevice corrosion resistance with increased heat intensity. Inner surfaces of welds have shown severe oxide cracking and a remarkable weight loss when exposed to concentrated FeCl3. The weight loss was enhanced with decreased filler wire feed rate and increased heat intensity. 

Keywords: automobiles, welding, corrosion, lap joints, Micro XRD

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1869 Standardization of Propagation Techniques in Selected Native Plants of Kuwait

Authors: Laila Almulla, Narayana Bhat, Majda Suleiman, Sheena Jacob

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Biodiversity conservation has become one of the challenging priorities to combat species extinction for many countries, including the state of Kuwait. Since native plants are better adapted to the local environment, can endure long spells of drought, withstand high soil salinity levels and provide a more natural effect to landscape projects, their use will both conserve natural resources and produce sustainable greenery. When native plants are properly blended with naturalized exotic ornamental plants in a landscape, they can improve social and cultural benefits. Screening of exotic and native plants in Kuwait during the past two decades has led to the selection of some very promising plants. Continuation of evaluation of additional native and exotic plants is essential to increase diversity of plant resources for greenery projects. Therefore, an effort was made to evaluate further native plants for their suitability for greenery applications. In the present study, various treatments were used to mass multiply selected plants using seeds to secure maximum germination. Seeds were subjected to nine treatments, and each treatment was replicated five times with ten seeds per treatment unit. After the treatment, the seeds of Zygophyllum qatarense were incubated at 30 °C, three lights for 12 h, at 40% humidity; where as the seeds of Haloxylon salicornicum were incubated at 22 °C with continuous light, at 40% humidity. Soaking in 250-ppm GA3 resulted in highest germination percentage of 20% in Zygophyllum qatarense and, Soaking in 500-ppm GA3 resulted in 6% germination in Haloxylon salicornicum. Germination of the viable seeds is influenced by various external and internal factors, seed must not be in a state of dormancy and the environmental requirements for germination of that seed must be met, before germination can occur.

Keywords: landscape, native plants, revegetation, seed germination

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1868 Ingenious Use of Hypo Sludge in M25 Concrete

Authors: Abhinandan Singh Gill

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Paper mill sludge is one of the major economic and environmental problems for paper and board industry, million tonnes quantity of sludge is produced in the world. It is essential to dispose these wastes safely without affecting health of human being, environment, fertile land; sources of water bodies, economy as it adversely affect the strength, durability and other properties of building materials based on them. Moreover, in developing countries like India where there is low availability of non-renewable resources and large need of building material like cement therefore it is essential to develop eco-efficient utilization of paper sludge. Primarily in functional terms paper sludge comprises of cellulose fibers, calcium carbonate, china clay, low silica, residual chemical bonds with water. The material is sticky and full of moisture content which is hard to dry. The manufacturing of paper usually produce loads of solid waste. These paper fibers are recycled in paper mills to limited number of times till they become weak to produce high quality paper. Thereafter, these left out small and weak pieces called as low quality paper fibers are detached out to become paper sludge. The material is by-product of de-inking and re-pulping of paper. This hypo sludge includes all kinds of inks, dyes, coating etc inscribed on the paper. This paper presents an overview of the published work on the use of hypo sludge in M25 concrete formulations as a supplementary cementitious material exploring its properties such as compressive strength, splitting and parameters like modulus of elasticity, density, applications and most importantly investigation of low cost concrete by using hypo sludge are presented.

Keywords: concrete, sludge waste, hypo sludge, supplementary cementitious material

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1867 Experimental Study for Examination of Nature of Diffusion Process during Wine Microoxygenation

Authors: Ilirjan Malollari, Redi Buzo, Lorina Lici

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This study was done for the characterization of polyphenols changes of anthocyanins, flavonoids, the color intensity and total polyphenols index, maturity and oxidation index during the process of micro-oxygenation of wine that comes from a specific geographic area in the southeastern region of the country. Also, through mathematical modeling of the oxygen distribution within solution of wort for wine fermentation, was shown the strong impact of carbon dioxide present in the liquor. Analytical results show periodic increases of color intensity and tonality, reduction level of free anthocyanins and flavonoids free because of polycondensation reactions between tannins and anthocyanins, increased total polyphenols index and decrease the ratio between the flavonoids and anthocyanins offering a red stabilize wine proved by sensory degustation tasting for color intensity, tonality, body, tannic perception, taste and remained back taste which comes by specific area associated with environmental indications. Micro-oxygenation of wine is a wine-making technique, which consists in the addition of small and controlled amounts of oxygen in the different stages of wine production but more efficiently after end of alcoholic fermentation. The objectives of the process include improved mouth feel (body and texture), color enhanced stability, increased oxidative stability, and decreased vegetative aroma during polyphenols changes process. A very important factor is polyphenolics organic grape composition strongly associated with the environment geographical specifics area in which it is grown the grape.

Keywords: micro oxygenation, polyphenols, environment, wine stability, diffusion modeling

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1866 Integrated Dynamic Analysis of Semi-Submersible Flap Type Concept

Authors: M. Rafiur Rahman, M. Mezbah Uddin, Mohammad Irfan Uddin, M. Moinul Islam

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With a rapid development of offshore renewable energy industry, the research activities in regards of harnessing power from offshore wind and wave energy are increasing day by day. Integration of wind turbines and wave energy converters into one combined semi-submersible platform might be a cost-economy and beneficial option. In this paper, the coupled integrated dynamic analysis in the time domain (TD) of a simplified semi-submersible flap type concept (SFC) is accomplished via state-of-the-art numerical code referred as Simo-Riflex-Aerodyn (SRA). This concept is a combined platform consisting of a semi-submersible floater supporting a 5 MW horizontal axis wind turbine (WT) and three elliptical shaped flap type wave energy converters (WECs) on three pontoons. The main focus is to validate the numerical model of SFC with experimental results and perform the frequency domain (FD) and TD response analysis. The numerical analysis is performed using potential flow theory for hydrodynamics and blade element momentum (BEM) theory for aerodynamics. A variety of environmental conditions encompassing the functional & survival conditions for short-term sea (1-hour simulation) are tested to evaluate the sustainability of the SFC. The numerical analysis is performed in full scale. Finally, the time domain analysis of heave, pitch & surge motions is performed numerically using SRA and compared with the experimental results. Due to the simplification of the model, there are some discrepancies which are discussed in brief.

Keywords: coupled integrated dynamic analysis, SFC, time domain analysis, wave energy converters

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1865 Study of Compatibility and Oxidation Stability of Vegetable Insulating Oils

Authors: Helena M. Wilhelm, Paulo O. Fernandes, Laís P. Dill, Kethlyn G. Moscon

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The use of vegetable oil (or natural ester) as an insulating fluid in electrical transformers is a trend that aims to contribute to environmental preservation since it is biodegradable and non-toxic. Besides, vegetable oil has high flash and combustion points, being considered a fire safety fluid. However, vegetable oil is usually less stable towards oxidation than mineral oil. Both insulating fluids, mineral and vegetable oils, need to be tested periodically according to specific standards. Oxidation stability can be determined by the induction period measured by conductivity method (Rancimat) by monitoring the effectivity of oil’s antioxidant additives, a methodology already developed for food application and biodiesel but still not standardized for insulating fluids. Besides adequate oxidation stability, fluids must be compatible with transformer's construction materials under normal operating conditions to ensure that damage to the oil and parts of the transformer does not occur. ASTM standard and Brazilian normative differ in parameters evaluated, which reveals the need to regulate tests for each oil type. The aim of this study was to assess oxidation stability and compatibility of vegetable oils to suggest the best way to assure a viable performance of vegetable oil as transformer insulating fluid. The determination of the induction period for several vegetable insulating oils from the local market by using Rancimat was carried out according to BS EN 14112 standard, at different temperatures (110, 120, and 130 °C). Also, the compatibility of vegetable oil was assessed according to ASTM and ABNT NBR standards. The main results showed that the best temperature for use in the Rancimat test is 130 °C, which allows a better observation of conductivity change. The compatibility test results presented differences between vegetable and mineral oil standards that should be taken into account in oil testing since materials compatibility and oxidation stability are essential for equipment reliability.

Keywords: compatibility, Rancimat, natural ester, vegetable oil

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1864 Structure-Activity Relationship of Gold Catalysts on Alumina Supported Cu-Ce Oxides for CO and Volatile Organic Compound Oxidation

Authors: Tatyana T. Tabakova, Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Krasimir I. Ivanov, Yordanka G. Karakirova, Petya Cv. Petrova, Georgi V. Avdeev

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The catalytic oxidation of CO and volatile organic compounds (VOCs) is considered as one of the most efficient ways to reduce harmful emissions from various chemical industries. The effectiveness of gold-based catalysts for many reactions of environmental significance was proven during the past three decades. The aim of this work was to combine the favorable features of Au and Cu-Ce mixed oxides in the design of new catalytic materials of improved efficiency and economic viability for removal of air pollutants in waste gases from formaldehyde production. Supported oxides of copper and cerium with Cu: Ce molar ratio 2:1 and 1:5 were prepared by wet impregnation of g-alumina. Gold (2 wt.%) catalysts were synthesized by a deposition-precipitation method. Catalysts characterization was carried out by texture measurements, powder X-ray diffraction, temperature programmed reduction and electron paramagnetic resonance spectroscopy. The catalytic activity in the oxidation of CO, CH3OH and (CH3)2O was measured using continuous flow equipment with fixed bed reactor. Both Cu-Ce/alumina samples demonstrated similar catalytic behavior. The addition of gold caused significant enhancement of CO and methanol oxidation activity (100 % degree of CO and CH3OH conversion at about 60 and 140 oC, respectively). The composition of Cu-Ce mixed oxides affected the performance of gold-based samples considerably. Gold catalyst on Cu-Ce/γ-Al2O3 1:5 exhibited higher activity for CO and CH3OH oxidation in comparison with Au on Cu-Ce/γ-Al2O3 2:1. The better performance of Au/Cu-Ce 1:5 was related to the availability of highly dispersed gold particles and copper oxide clusters in close contact with ceria.

Keywords: CO and VOCs oxidation, copper oxide, Ceria, gold catalysts

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1863 Design Intervention to Achieve Space Efficiency for Commercial Interiors

Authors: Hari Krishna Ayyappa, Reenu Singh

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Rising population and restricted land for development has led towards the growth of vertical buildings and small complexes. It provides many possibilities to change the shape and size of internal space in addition to the social impacts on the commercial spaces. With the increased volatility of necessities of people, the need for mental and physical comfort has continuously increased. . Living in a small space musts minimalist and space- saving cabinetwork results to sustain mortal good. This paper attempts to explore the Influence of Using Minimalist Furniture on the Efficiency of the commercial Space interiors by means of the variable resulting from preceding studies based on literature. A literature review was conducted on research articles to understand the contributing variables in a well designed small commercial spaces. A questionnaire survey was conducted to understand the layout of small commercial spaces with respect to Environmental impact, material, Design elements, Modern approach, Layered lightings, and colours. The problem of small spaces can be resolved by some ways; it's still needed for cabinetwork to develop to be more innovative to accommodate small living spaces. Since cabinetwork is a necessity and not luxury, everybody is in need of it. The spatial factors affecting overall satisfaction at a detailed position were bandied. The variable helped in proposing design ideation and mock ups to explore improved interiors. This paper concludes that most of the principles of the minimalist approach have been overlooked at, which had an impact on the space efficiency in commercial spaces like storage rooms, office area, retail stores, restaurants, and other spaces where business is conducted.

Keywords: materials, modern approach, space efficiency, tall commercial buildings

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1862 A Theoretical Framework: The Influence of Luxury Companies' Corporate Social Activities on Consumer Purchase Intention

Authors: Kveta Olsanova, Gina Cook, Marija Zlatic

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This paper discusses the theoretical framework suggesting the dependencies between luxury brands’ CSR (Corporate Social Responsibility) variables and the purchase intention of luxury shoppers. The framework is based on a literature review and in-depth individual interviews with a sample of luxury users and buyers. The measures of the model are based on existing research and the authors' qualitative research results. The model suggests that purchase intention in the luxury segment is dependent on the luxury values (symbolic, experiential, functional and social), individual sustainable dimension (composed of societal, environmental and economic variables) and awareness of the brand’s CSR, the last two relationships being potentially moderated by certain conditions such as demographics and general attitudes towards CSR and sustainability. The model’s output is in the formulation of several hypotheses, to be tested in an upcoming quantitative study. The qualitative phase indicated that the perceived symbolic, functional and experiential value dimensions of luxury brands were stronger drivers of purchase intention compared to the sustainable dimension. The contribution of the research consists of highlighting CSR’s impact on customer purchase intent as a potential implication for luxury brand management due to two aspects: (i) consumer awareness of the existing CSR activities of luxury brands is low, and this might be challenged by the demands of Gen Z entrants into the lux industry as they are known for their positive approach to CSR; (ii) the UN’s SDGs will bring CSR to the attention of all industries, including currently 'CSR silent' segments represented by luxury. Our research should contribute to incorporation of strategic CSR into the policies and strategies of the luxury segment by providing evidence that luxury customers do care.

Keywords: CSR, luxury shoppers, purchase intention, sustainability

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1861 Fuzzy Control of Thermally Isolated Greenhouse Building by Utilizing Underground Heat Exchanger and Outside Weather Conditions

Authors: Raghad Alhusari, Farag Omar, Moustafa Fadel

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A traditional greenhouse is a metal frame agricultural building used for cultivation plants in a controlled environment isolated from external climatic changes. Using greenhouses in agriculture is an efficient way to reduce the water consumption, where agriculture field is considered the biggest water consumer world widely. Controlling greenhouse environment yields better productivity of plants but demands an increase of electric power. Although various control approaches have been used towards greenhouse automation, most of them are applied to traditional greenhouses with ventilation fans and/or evaporation cooling system. Such approaches are still demanding high energy and water consumption. The aim of this research is to develop a fuzzy control system that minimizes water and energy consumption by utilizing outside weather conditions and underground heat exchanger to maintain the optimum climate of the greenhouse. The proposed control system is implemented on an experimental model of thermally isolated greenhouse structure with dimensions of 6x5x2.8 meters. It uses fans for extracting heat from the ground heat exchanger system, motors for automatic open/close of the greenhouse windows and LED as lighting system. The controller is integrated also with environmental condition sensors. It was found that using the air-to-air horizontal ground heat exchanger with 90 mm diameter and 2 mm thickness placed 2.5 m below the ground surface results in decreasing the greenhouse temperature of 3.28 ˚C which saves around 3 kW of consumed energy. It also eliminated the water consumption needed in evaporation cooling systems which are traditionally used for cooling the greenhouse environment.

Keywords: automation, earth-to-air heat exchangers, fuzzy control, greenhouse, sustainable buildings

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1860 Sustainable Renovation of Cultural Buildings Case Study: Red Bay National Historic Site, Canada

Authors: Richard Briginshaw, Hana Alaojeli, Javaria Ahmad, Hamza Gaffar, Nourtan Murad

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Sustainable renovations to cultural buildings and sites require a high level of competency in the sometimes conflicting areas of social/historical demands, environmental concerns, and the programmatic and technical requirements of the project. A detailed analysis of the existing site, building and client program are critical to reveal both challenges and opportunities. This forms the starting point for the design process – empirical explorations that search for a balanced and inspired architectural solution to the project. The Red Bay National Historic Site on the Labrador Coast of eastern Canada is a challenging project to explore and resolve these ideas. Originally the site of a 16ᵗʰ century whaling station occupied by Basque sailors from France and Spain, visitors now experience this history at the interpretive center, along with the unique geography, climate, local culture and vernacular architecture of the area. Working with our client, Parks Canada, the project called for significant alterations and expansion to the existing facility due to an increase in the number of annual visitors. Sustainable aspects of the design are focused on sensitive site development, passive energy strategies such as building orientation and building envelope efficiency, active renewable energy systems, carefully considered material selections, water efficiency, and interiors that respond to human comfort and a unique visitor experience.

Keywords: sustainability, renovations and expansion, cultural project, architectural design, green building

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1859 Nurse´s Interventions in Patients with Dementia During Clinical Practice: A Literature Review

Authors: Helga Martins, Idália Matias

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Background: Dementia is an important research topic since that life expectancy worldwide is increasing, so people are getting older. The aging of populations has a major impact on the increase in dementia, and nurses play a major role in taking care of these patients. Therefore, the implementation of nursing interventions based on evidence is vital so that we are aware of what we can do in clinical practice in order to provide patient cantered care to patients with dementia. Aim: To identify the nurse´s interventions in patients with dementia during clinical practice. Method: Literature review grounded on an electronic search in the EBSCOhost platform (CINAHL Plus with Full Text, MEDLINE with Full Text, and Nursing & Allied Health Collection), using the search terms of "dementia" AND "nurs*" AND “interventions” in the abstracts. The inclusion criteria were: original papers published up to June 2021. A total of 153 results after de duplicate removal we kept 104. After the application of the inclusion criteria, we included 15 studies This literature review was performed by two independent researchers. Results: A total of 15 results about nurses’ interventions in patients with dementia were included in the study. The major interventions are therapeutic communication strategies, environmental management of stressors involving family/caregivers; strategies to promote patient safety, and assistance in activities of daily living in patients who are clinically deteriorated. Conclusion: Taking care of people with dementia is a complex and demanding task. Nurses are required to have a set of skills and competences in order to provide nursing interventions. We highlight that is necessary an awareness in nursing education regarding providing nursing care to patients with dementia.

Keywords: dementia, interventions, nursing, review

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1858 Statistical Modelling of Maximum Temperature in Rwanda Using Extreme Value Analysis

Authors: Emmanuel Iyamuremye, Edouard Singirankabo, Alexis Habineza, Yunvirusaba Nelson

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Temperature is one of the most important climatic factors for crop production. However, severe temperatures cause drought, feverish and cold spells that have various consequences for human life, agriculture, and the environment in general. It is necessary to provide reliable information related to the incidents and the probability of such extreme events occurring. In the 21st century, the world faces a huge number of threats, especially from climate change, due to global warming and environmental degradation. The rise in temperature has a direct effect on the decrease in rainfall. This has an impact on crop growth and development, which in turn decreases crop yield and quality. Countries that are heavily dependent on agriculture use to suffer a lot and need to take preventive steps to overcome these challenges. The main objective of this study is to model the statistical behaviour of extreme maximum temperature values in Rwanda. To achieve such an objective, the daily temperature data spanned the period from January 2000 to December 2017 recorded at nine weather stations collected from the Rwanda Meteorological Agency were used. The two methods, namely the block maxima (BM) method and the Peaks Over Threshold (POT), were applied to model and analyse extreme temperature. Model parameters were estimated, while the extreme temperature return periods and confidence intervals were predicted. The model fit suggests Gumbel and Beta distributions to be the most appropriate models for the annual maximum of daily temperature. The results show that the temperature will continue to increase, as shown by estimated return levels.

Keywords: climate change, global warming, extreme value theory, rwanda, temperature, generalised extreme value distribution, generalised pareto distribution

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1857 Geographical Parthenogenesis in Plants

Authors: Elvira Hörandl

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The term “Geographical parthenogenesis” describes the phenomenon that asexual organisms usually occupy larger and more northern distribution areas than their sexual relatives and tend to colonize previously glaciated areas. Several case studies in flowering plants confirm the geographical pattern, but the causal factors behind the phenomenon are still unclear. Previous authors regarded predominant polyploidy in asexual (apomictic) plants as the main factor. However, the geographical pattern is not the rule for sexual polyploids. Recent research confirmed a previous hypothesis of the author that a combination of factors is acting: Although uniparental reproduction provides better colonization abilities, it is most efficient in combination with polyploidy. I will present results on case studies in the genus Ranunculus of both autopolyploid and allopolyploid species and species complexes reproducing via facultative apomixis. Polyploidy seems to contribute mainly to a better tolerance of colder climates and temperate extremes, whereby epigenetic flexibility, changes in gene expression, and phenotypic plasticity play an important role in occupying ecological niches under harsh conditions. Phylogenomic studies entangle complex hybrid origins of asexual taxa, which increases intragenomic heterozygosity of asexual plants. Interestingly, our results suggest an association of sexuality with abiotic stresses, specifically with light stress, which might explain that still, most plants in high altitudes and in southern areas retain sexual reproduction despite other climatic conditions that would favor apomictic plants. We conclude that geographical parthenogenesis results from the complex interplay of the genomic constitution, mode of reproduction and environmental factors.

Keywords: apomixis, polyploidy, hybridization, abiotic stress, epigenetics, phylogenomics

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1856 Cultural Psychology in Sports: How Understanding Culture May Help Sports Psychologists Augment Athletic Performance

Authors: Upasana Ranjib

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Sports psychology, as a niche area, has, since the last two decades, found for itself a space within the outer peripheries of the discipline of traditional psychology. It has aimed to understand the many variables that push athletes to enhance their performances. While sociological aspects have been duly represented in academia, little has been written about the role of culture in shaping the psyche of athletes. The impact that cultures of different communities and societies have towards specifics like gender, castes, religion and race and how that helps evolve an individual has not been fully addressed. In the case of Sport, culture has made itself felt in the form of stereotypes, traditional outlooks towards sects and its implication on the engagement with sports. Culture is an environment that an individual imbibes. It is what shapes him, physically as well as mentally. Their nurture and nature both stem from it and depend on it. To realize the linkages between their nurture, nature and sports efficiency, cultural studies must collaborate in scholarship with psychology and practical sports. Cultural sports psychology would allow sports psychologists, coaches and even athletes themselves to understand the behavioural variations that affect their performance. The variations in the performance of athletes from different cultures and countries could be attributed to their socio-political, economic and environmental differences. These cultural influences shape and impact the athlete's behaviour and might lead as a gateway to understanding their skill sets and internal motivational factors. With that knowledge in mind, this paper aims to understand and reflect on how, in the present times of heavy sporting competition, shifting cultural equations and changing world dynamics, it is mandatory to infuse Cultural Studies with Sports Psychology to understand how Sports Psychologists can help and augment the performances of athletes.

Keywords: sporting performance, Asian sports, sports psychology, cultural psychology, society

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1855 The Interplay of Community-based Social Capital and Neighbourhood Dynamics in Enhancing SMEs’ Resilience During Crises: A Fuzzy-Set Qualitative Comparative Analysis Approach

Authors: Arash Sadeghi, Taimaz Larimian

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This study explores the intricate interplay between community-based social capital (CBSC) and neighbourhood dynamics in enhancing resilience of Iranian SMEs, particularly under the strain of international sanctions. Utilising fuzzy-set Qualitative Comparative Analysis (fsQCA), we examine how different dimensions of CBSC—structural, relational, and cognitive—interact with neighbourhood socio-economic and built-environment characteristics to influence SME resilience. Findings reveal four configurations that contribute to the presence of resistance and five configurations associated with the adaptation outcome. Each configuration demonstrates a distinct combination of social capital elements, which vary according to the specific socio-economic and built-environmental characteristics of the neighbourhoods. The first configuration highlights the importance of structural social capital in deprived areas for building resistance, while the second emphasises the role of relational social capital in low-density, minimally deprived areas. Overall, cognitive social capital seems to be less effective in driving economic resilience compared to structural and relational types. This research contributes to the literature by providing a nuanced understanding of the synergistic effects of CBSC dimensions and neighbourhood characteristics on SME resilience. By adopting a configurational approach, we move beyond traditional methodologies, offering a comprehensive view of the complex dynamics of CBSC and neighbourhood characteristics and their impact on SME resilience in varying neighbourhoods.

Keywords: community-based social capital, fuzzy-set qualitative comparative analysis (fsQCA), place-based resilience, resistance

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1854 Investigation and Analysis of Residential Building Energy End-Use Profile in Hot and Humid Area with Reference to Zhuhai City in China

Authors: Qingqing Feng, S. Thomas Ng, Frank Xu

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Energy consumption in domestic sector has been increasing rapidly in China all along these years. Confronted with environmental challenges, the international society has made a concerted effort by setting the Paris Agreement, the Sustainable Development Goals, and the New Urban Agenda. Thus it’s very important for China to put forward reasonable countermeasures to boost building energy conservation which necessitates looking into the actuality of residential energy end-use profile and its influence factors. In this study, questionnaire surveys have been conducted in Zhuhai city in China, a typical city in hot summer warm winter climate zone. The data solicited mainly include the occupancy schedule, building’s information, residents’ information, household energy uses, the type, quantity and use patterns of appliances and occupants’ satisfaction. Over 200 valid samples have been collected through face-to-face interviews. Descriptive analysis, clustering analysis, correlation analysis and sensitivity analysis were then conducted on the dataset to understand the energy end-use profile. The findings identify: 1) several typical clusters of occupancy patterns and appliances utilization patterns; 2) the top three sensitive factors influencing energy consumption; 3) the correlations between satisfaction and energy consumption. For China with many different climates zones, it’s difficult to find a silver bullet on energy conservation. The aim of this paper is to provide a theoretical basis for multi-stakeholders including policy makers, residents, and academic communities to formulate reasonable energy saving blueprints for hot and humid urban residential buildings in China.

Keywords: residential building, energy end-use profile, questionnaire survey, sustainability

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1853 Towards Resilient and Sustainable Integrated Agro-ecosystems Through Appropriate Climate-smart Farming Practices in Morocco Rainfed Agriculture

Authors: Abdelali Laamari, Morad Faiz, Ali Amamou And Mohamed Elkoudrim

Abstract:

This research seeks to develop multi-disciplinary, multi-criteria, and multi-institutional approaches that consider the three main pillars of sustainability (environmental, economic, and social aspects) at the level of decision making regarding the adoption of improved technologies in the targeted case study region in Morocco. The study is aimed at combining sound R&I with extensive skills in applied research and policy evaluation. The intention is to provide new simple, and transferable tools and agricultural practices that will enable the uptake of sustainability and the resiliency of agro-ecosystems. The study will understand the state-of-the-art of the impact of climate change and identify the core bottlenecks and climate change’s impact on crop and livestock productivity of the targeted value chains in Morocco. Studies conducted during 2021-2022 showed that most of the farmers are using since 2010 the direct seeding and the system can be improved by adopting new fertilizer and varieties of wheat. The alley-cropping technology is based on Atriplex plant or olive trees. The introduction of new varieties of oat and quinoa has improved biomass and grain production in a dry season. The research is targeting other issues, such as social enterprises, to diversify women’s income resources and create new job opportunities through diversification of end uses of durum wheat and barley grains. Women’s local knowledge is rich on the different end uses of durum and barley grains that can improve their added value if they are transformed as couscous, pasta, or any other products.

Keywords: agriculture, climate, production system, integration

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1852 Passive Attenuation of Nitrogen Species at Northern Mine Sites

Authors: Patrick Mueller, Alan Martin, Justin Stockwell, Robert Goldblatt

Abstract:

Elevated concentrations of inorganic nitrogen (N) compounds (nitrate, nitrite, and ammonia) are a ubiquitous feature to mine-influenced drainages due to the leaching of blasting residues and use of cyanide in the milling of gold ores. For many mines, the management of N is a focus for environmental protection, therefore understanding the factors controlling the speciation and behavior of N is central to effective decision making. In this paper, the passive attenuation of ammonia and nitrite is described for three northern water bodies (two lakes and a tailings pond) influenced by mining activities. In two of the water bodies, inorganic N compounds originate from explosives residues in mine water and waste rock. The third water body is a decommissioned tailings impoundment, with N compounds largely originating from the breakdown of cyanide compounds used in the processing of gold ores. Empirical observations from water quality monitoring indicate nitrification (the oxidation of ammonia to nitrate) occurs in all three waterbodies, where enrichment of nitrate occurs commensurately with ammonia depletion. The N species conversions in these systems occurred more rapidly than chemical oxidation kinetics permit, indicating that microbial mediated conversion was occurring, despite the cool water temperatures. While nitrification of ammonia and nitrite to nitrate was the primary process, in all three waterbodies nitrite was consistently present at approximately 0.5 to 2.0 % of total N, even following ammonia depletion. The persistence of trace amounts of nitrite under these conditions suggests the co-occurrence denitrification processes in the water column and/or underlying substrates. The implications for N management in mine waters are discussed.

Keywords: explosives, mining, nitrification, water

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1851 Biofuel Production via Thermal Cracking of Castor Methyl Ester

Authors: Roghaieh Parvizsedghy, Seyed Mojtaba Sadrameli

Abstract:

Diminishing oil reserves, deteriorating health standards because of greenhouse gas emissions and associated environmental impacts have emerged biofuel production. Vegetable oils are proved to be valuable feedstock in these growing industries as they are renewable and potentially inexhaustible sources. Thermal Cracking of vegetable oils (triglycerides) leads to production of biofuels which are similar to fossil fuels in terms of composition but their combustion and physical properties have limits. Acrolein (very poisonous gas) and water production during cracking of triglycerides occurs because of presence of glycerin in their molecular structure. Transesterification of vegetable oil is a method to extract glycerol from triglycerides structure and produce methyl ester. In this study, castor methyl ester was used for thermal cracking in order to survey the efficiency of this method to produce bio-gasoline and bio-diesel. Thus, several experiments were designed by means of central composite method. Statistical studies showed that two reaction parameters, namely cracking temperature and feed flowrate, affect products yield significantly. At the optimized conditions (480 °C and 29 g/h) for maximum bio-gasoline production, 88.6% bio-oil was achieved which was distilled and separated as bio-gasoline (28%) and bio-diesel (48.2%). Bio-gasoline exposed a high octane number and combustion heat. Distillation curve and Reid vapor pressure of bio-gasoline fell in the criteria of standard gasoline (class AA) by ASTM D4814. Bio-diesel was compatible with standard diesel by ASTM D975. Water production was negligible and no evidence of acrolein production was distinguished. Therefore, thermal cracking of castor methyl ester could be used as a method to produce valuable biofuels.

Keywords: bio-diesel, bio-gasoline, castor methyl ester, thermal cracking, transesterification

Procedia PDF Downloads 211
1850 The Architectural Conservation and Restoration Problems of Istanbul’s “Yalı” Waterfront Mansions

Authors: Zeynep Tanrıverdi

Abstract:

The Bosphorus is an international waterway in Istanbul city of Turkey connecting the Sea of Marmara and the Black Sea. The Bosphorus, which has formed an important part of the silhouette of Istanbul throughout history, has also influenced the design of the coastal structures built around it. The waterfront mansions, which are located on both sides of the Bosphorus by the sea, and can be generally of two or three storeys, are called “yalı”. The yalı buildings with their architectural characteristics of the traditional Turkish House are the most grandiose examples of Ottoman residential architecture. However, the classical Ottoman yalı architecture of the 18th century can only be seen in engravings, and today only the modest and smaller yalı examples from the 19th century can be seen because of their disappearance over time. The study aims to reveal the architectural conservation and restoration problems of waterfront mansions and propose solutions for them. Firstly, the development of the waterfront mansion architecture in Bosphorus was evaluated in its historical process. Secondly, the waterfront mansions and their architectural features were explained. Thirdly, the architectural conservation and restoration problems that caused the disappearance of waterfront mansions were discussed. These problems include disruptions in legal regulations and practices about the Bosphorus, dramatic changes in Turkey’s socio-cultural life from the Ottoman Empire to the present, inadequacies in economic resources, negative environmental effects, and errors in restoration works. Finally, solution suggestions were proposed for the problems that threaten the protection of waterfront mansions. In the study, literature on waterfront mansions was reviewed using historical reports, photographs, maps, and drawings in archival documents. It is hoped that this study will contribute the conservation of the “Yalı” waterfront mansions, which occupy a particular role in the cultural heritage of Turkey, and to their transmission with their authentic values to the next generation.

Keywords: bosphorus architecture, conservation, heritage, Istanbul, waterfront mansions (yalı)

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1849 Genetic and Phenotypic Variability Among the Vibrio Cholerae O1 Isolates of India

Authors: Sreeja Shaw, Prosenjit Samanta, Asish Kumar Mukhopadhyay

Abstract:

Cholera is still a global public health burden and is caused by Vibrio cholerae O1 and O139 serogroups. Evidence from recent outbreaks in Haiti and Yemen suggested that circulating V. cholerae O1 El Tor variant strains are continuously changing to cause more ruinous outbreaks worldwide, and most of them have emerged from the Indian subcontinents. Therefore, we studied the changing virulence characteristics along with the antibiotic resistance profile of V. cholerae O1strains isolated from seasonal outbreaks in three cholera endemic regions during 2018, Gujarat and Maharashtra in Western India (87 strains), and to compare those features with the isolates of West Bengal in Eastern India (48 strains) collected during the same period. All the strains from Western India were of Ogawa serotype, polymyxin B-sensitive, hemolytic, and contained a large fragment deletion in VSP-II genomic region similar with Yemen outbreak strains and carried more virulent Haitian genetic alleles of major virulence associated genes ctxB, tcpA, and rtxA. Conversely, 14.6% (7/48) of the strains from Eastern India were belong to the Inaba serotype, polymyxin B-resistant, non-hemolytic, harbored intact VSP-II region, classical ctxB, Haitian tcpA, and El Tor rtxA alleles. Interestingly, resistance to tetracycline and chloramphenicol was seen in isolates from both regions, which are not very common among V. cholerae O1 isolates in India. Therefore, this study indicated West Bengal as a diverse region where two different types of El Tor variant hypervirulent strains are co-existed, probably competing for their better environmental survival, which may result in severe irrepressible disease outcome in the future.

Keywords: cholera, vibrio cholerae, polymyxin B, Non-hemolytic, ctxB, tcpA, rtxA, VSP-II

Procedia PDF Downloads 135
1848 Salt-Induced Modulation in Biomass Production, Pigment Concentration, Ion Accumulation, Antioxidant System and Yield in Pea Plant

Authors: S. Noreen, S. Ahmad

Abstract:

Salinity is one of the most important environmental factors that limit the production of crop plants to the greatest proportion than any other ones. Salt-induced changes in growth, pigment concentration, water status, malondialdehydes (MDA) and H₂O₂ content, enzymatic and non-enzymatic antioxidants, Na⁺, K⁺ content and yield attributes were examined in the glasshouse on ten pea (Pisum Sativum L.) accessions, namely ‘13240’, ‘18302’, ‘19666’, ‘19700’, ‘19776’, ‘19785’, ‘19788’, ‘20153’, ‘20155’, ‘26719’ were subjected to non-stress (0 mM NaCl) and salt stress (100 mM and150 mM NaCl) in pots containing sand medium. The results showed that salt stress at level150 mM substantially reduced biomass production, leaf water status, pigment concentration (chlorophyll ‘a’, ‘b’, ‘carotenoid content’ total chlorophyll), K⁺ content, quantum yield and yield attributes as compared to plants treated with 100 mM NaCl. Antioxidant enzymes, Catalase (CAT), Peroxidase (POD), Superoxide dismutase (SOD) and Ascorbate peroxidase (APX), proline content, total soluble protein, total amino acids, Malondialdehyde content (MDA), Hydrogen peroxide (H₂O₂) content and Na⁺ uptake markedly enhanced due to the influence of salt stress. On the basis of analyses (expressed as percent of control), of 10 accessions of pea plant, two were ranked as salt tolerant namely (‘19666’, ‘20153’), four were moderately tolerant namely (‘19700’, ‘19776’, ‘19785’, ‘20155’), and three were salt sensitive namely (‘13240’, ‘18302’, ‘26719’) at 150 mM NaCl level.

Keywords: antioxidant enzymes, ion uptake, pigment concentration, salt stress, yield attributes

Procedia PDF Downloads 79
1847 Improvement of the Mechanical Behavior of an Environmental Concrete Based on Demolished

Authors: Larbi Belagraa

Abstract:

The universal need to conserve resources, protect the environment and use energy efficiently must necessarily be felt in the field of concrete technology. The recycling of construction and demolition waste as a source of aggregates for the production of concrete has attracted growing interest from the construction industry. In Algeria, the depletion of natural deposits of aggregates and the difficulties in setting up new quarries; makes it necessary to seek new sources of supply, to meet the need for aggregates for the major projects launched by the Algerian government in the last decades. In this context, this work is a part of the approach to provide answers to concerns about the lack of aggregates for concrete. It also aims to develop the inert fraction of demolition materials and mainly concrete construction demolition waste(C&D) as a source of aggregates for the manufacture of new hydraulic concretes based on recycled aggregates. This experimental study presents the results of physical and mechanical characterizations of natural and recycled aggregates, as well as their influence on the properties of fresh and hardened concrete. The characterization of the materials used has shown that the recycled aggregates have heterogeneity, a high water absorption capacity, and a medium quality hardness. However, the limits prescribed by the standards in force do not disqualify these materials of use for application as recycled aggregate concrete type (RAC). The results obtained from the present study show that acceptable mechanical, compressive, and flexural strengths of RACs are obtained using Superplasticizer SP 45 and 5% replacement of cement with silica fume based on recycled aggregates, compared to those of natural concretes. These mechanical performances demonstrate a characteristic resistance at 28 days in compression within the limits of 30 to 40 MPa without any particular suitable technology .to be adapted in the case.

Keywords: recycled aggregates, concrete(RAC), superplasticizer, silica fume, compressive strength

Procedia PDF Downloads 146
1846 An Explanatory Study Approach Using Artificial Intelligence to Forecast Solar Energy Outcome

Authors: Agada N. Ihuoma, Nagata Yasunori

Abstract:

Artificial intelligence (AI) techniques play a crucial role in predicting the expected energy outcome and its performance, analysis, modeling, and control of renewable energy. Renewable energy is becoming more popular for economic and environmental reasons. In the face of global energy consumption and increased depletion of most fossil fuels, the world is faced with the challenges of meeting the ever-increasing energy demands. Therefore, incorporating artificial intelligence to predict solar radiation outcomes from the intermittent sunlight is crucial to enable a balance between supply and demand of energy on loads, predict the performance and outcome of solar energy, enhance production planning and energy management, and ensure proper sizing of parameters when generating clean energy. However, one of the major problems of forecasting is the algorithms used to control, model, and predict performances of the energy systems, which are complicated and involves large computer power, differential equations, and time series. Also, having unreliable data (poor quality) for solar radiation over a geographical location as well as insufficient long series can be a bottleneck to actualization. To overcome these problems, this study employs the anaconda Navigator (Jupyter Notebook) for machine learning which can combine larger amounts of data with fast, iterative processing and intelligent algorithms allowing the software to learn automatically from patterns or features to predict the performance and outcome of Solar Energy which in turns enables the balance of supply and demand on loads as well as enhance production planning and energy management.

Keywords: artificial Intelligence, backward elimination, linear regression, solar energy

Procedia PDF Downloads 136
1845 Silver Nanoparticle Application in Food Packaging and Impacts on Food Safety and Consumer’s Health

Authors: Worku Dejene Bekele, András Marczika Csilla Sörös

Abstract:

Silver nanoparticles are silver metal with a size of 1-100nm. The most common source of silver nanoparticles is inorganic salts. Nanoparticles can be ingested through our foods and constitute nanoparticles and silver ions, whether as an additive or by migrants and, in some cases, as a pollutant. Silver nanoparticles are the most widely applicable engineered nanomaterials, especially for antimicrobial function. Ag nanoparticles give different advantages in the case of food safety, quality, and overall acceptability; however, they affect the health of humans and animals, putting them at risk of health problems and environmental pollution. Silver nanoparticles have been used widely in food packaging technologies, especially in water treatments, meat and meat products, fruit, and many other food products. This is for bio-preservation from food products. The primary goal of this review is to determine the safety and health impact of Ag nanoparticles application in food packaging and analysis of the human organs more affected by this preservative technology, to assess the implications of a nanoparticle on food safety, to determine the effects of nanoparticles on consumers health and to determine the impact of nanotechnology on product acceptability. But currently, much research has demonstrated that there is cause to believe that silver nanoparticles may have toxicological effects on biological organs and systems. The silver nanoparticles affect DNA expression, gastrointestinal barriers, lungs, and other breathing organs illness. Silver particles and molecules are very toxic. During its application in food packaging, food industries used the thinnest particle. This particle can potentially affect the gastrointestinal tracts-it suffers from mucus production, DNA, lungs, and other breezing organs. This review is targeted to demonstrate the knowledge gap that industrials use in the application of silver nanoparticles in food packaging and preservation and its health effects on the consumer.

Keywords: food preservatives, health impact, nanoparticle, silver nanoparticle

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1844 Efficiency of a Molecularly Imprinted Polymer for Selective Removal of Chlorpyrifos from Water Samples

Authors: Oya A. Urucu, Aslı B. Çiğil, Hatice Birtane, Ece K. Yetimoğlu, Memet Vezir Kahraman

Abstract:

Chlorpyrifos is an organophosphorus pesticide which can be found in environmental water samples. The efficiency and reuse of a molecularly imprinted polymer (chlorpyrifos - MIP) were investigated for the selective removal of chlorpyrifos residues. MIP was prepared with UV curing thiol-ene polymerization technology by using multifunctional thiol and ene monomers. The thiol-ene curing reaction is a radical induced process, however unlike other photoinitiated polymerization processes, this polymerization process is a free-radical reaction that proceeds by a step-growth mechanism, involving two main steps; a free-radical addition followed by a chain transfer reaction. It assures a very rapidly formation of a uniform crosslinked network with low shrinkage, reduced oxygen inhibition during curing and excellent adhesion. In this study, thiol-ene based UV-curable polymeric materials were prepared by mixing pentaerythritol tetrakis(3-mercaptopropionate), glyoxal bis diallyl acetal, polyethylene glycol diacrylate (PEGDA) and photoinitiator. Chlorpyrifos was added at a definite ratio to the prepared formulation. Chemical structure and thermal properties were characterized by FTIR and thermogravimetric analysis (TGA), respectively. The pesticide analysis was performed by gas chromatography-mass spectrometry (GC-MS). The influences of some analytical parameters such as pH, sample volume, amounts of analyte concentration were studied for the quantitative recoveries of the analyte. The proposed MIP method was applied to the determination of chlorpyrifos in river and tap water samples. The use of the MIP provided a selective and easy solution for removing chlorpyrifos from the water.

Keywords: molecularly imprinted polymers, selective removal, thilol-ene, uv-curable polymer

Procedia PDF Downloads 277