Search results for: chemical practices
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1787

Search results for: chemical practices

587 GIS-based Non-point Sources of Pollution Simulation in Cameron Highlands, Malaysia

Authors: M. Eisakhani, A. Pauzi, O. Karim, A. Malakahmad, S.R. Mohamed Kutty, M. H. Isa

Abstract:

Cameron Highlands is a mountainous area subjected to torrential tropical showers. It extracts 5.8 million liters of water per day for drinking supply from its rivers at several intake points. The water quality of rivers in Cameron Highlands, however, has deteriorated significantly due to land clearing for agriculture, excessive usage of pesticides and fertilizers as well as construction activities in rapidly developing urban areas. On the other hand, these pollution sources known as non-point pollution sources are diverse and hard to identify and therefore they are difficult to estimate. Hence, Geographical Information Systems (GIS) was used to provide an extensive approach to evaluate landuse and other mapping characteristics to explain the spatial distribution of non-point sources of contamination in Cameron Highlands. The method to assess pollution sources has been developed by using Cameron Highlands Master Plan (2006-2010) for integrating GIS, databases, as well as pollution loads in the area of study. The results show highest annual runoff is created by forest, 3.56 × 108 m3/yr followed by urban development, 1.46 × 108 m3/yr. Furthermore, urban development causes highest BOD load (1.31 × 106 kgBOD/yr) while agricultural activities and forest contribute the highest annual loads for phosphorus (6.91 × 104 kgP/yr) and nitrogen (2.50 × 105 kgN/yr), respectively. Therefore, best management practices (BMPs) are suggested to be applied to reduce pollution level in the area.

Keywords: Cameron Highlands, Land use, Non-point Sources of Pollution

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586 Mechanical and Chemical Properties of Zn-Ni-Al2O3 Nanocomposite Coatings

Authors: Soroor Ghaziof, Wei Gao

Abstract:

Zn alloy and composite coatings are widely used in buildings and structures, automobile and fasteners industries to protect steel component from corrosion. In this paper, Zn-Ni-Al2O3 nanocomposite coatings were electrodeposited on mild steel using a novel sol enhanced electroplating method. In this method, transparent Al2O3 sol was added into the acidic Zn-Ni bath to produced Zn-Ni- Al2O3 nanocomposite coatings. The effect of alumina sol on the electrodeposition process, and coating properties was investigated using cyclic voltammetry, XRD, ESEM and Tafel test. Results from XRD tests showed that the structure of all coatings was single γ- Ni5Zn21 phase. Cyclic voltammetry results showed that the electrodeposition overpotential was lower in the presence of alumina sol in the bath, and caused the reduction potential of Zn-Ni to shift to more positive values. Zn-Ni-Al2O3 nanocomposite coatings produced more uniform and compact deposits, with fine grained microstructure when compared to Zn-Ni coatings. The corrosion resistance of Zn-Ni coatings was improved significantly by incorporation of alumina nanoparticles into the coatings.

Keywords: Zn-Ni-Al2O3 composite coatings, steel, sol-enhanced electroplating, corrosion resistance.

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585 Utilization of Bioactive Components Produced from Fermented Soybean (Natto) in Beef Burger

Authors: F. M. Abu-Salem, M. H. Mahmoud, A. Y. Gibriel, M. H. El-Kalyoubi, A. A. Abou-Arab Arab

Abstract:

Soybean Natto powder was added to the burger in order to enhance the oxidative stability as well as decreases the microbial spoilage. The soybean bioactives compound (soybean Natto) as antioxidant and antimicrobial were added at level of 1, 2 and 3%. Chemical analysis and physical properties were affected by soybean Natto addition. All the tested soybean Natto additives showed strong antioxidant properties. The microbiological indicators were significantly (P < 0.05) affected by the addition of the soybean Natto. Decreasing trends of different extent were also observed in samples of the treatments for total viable counts, Coliform, Staphylococcus aureus, yeast and molds. Storage period was significantly (P < 0.05) affected on microbial counts in all samples Staphylococcus aureus were the most sensitive microbe followed by Coliform group of the sample containing soybean Natto. Sensory attributes were also performed, added soybean Natto exhibits beany flavor which was clear about samples of 3% soybean Natto.

Keywords: Antioxidant, antimicrobial, bioactive peptide, antioxidant peptides.

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584 Active Packaging Influence on Shelf Life Extension of Sliced Wheat Bread

Authors: Sandra Muizniece-Brasava, Lija Dukalska, Irisa Murniece, Ilona Dabina-Bicka, Emils Kozlinskis, Svetlana Sarvi, Ralfs Santars, Anna Silvjane

Abstract:

The research object was wheat bread. Experiments were carried out at the Faculty of Food Technology of the Latvia University of Agriculture. An active packaging in combination with modified atmosphere (MAP, CO2 60% and N2 40%) was examined and compared with traditional packaging in air ambiance. Polymer Multibarrier 60, PP and OPP bags were used. Influence of iron based oxygen absorber in sachets of 100 cc obtained from Mitsubishi Gas Chemical Europe Ageless® was tested on the quality during the shelf of wheat bread. Samples of 40±4 g were packaged in polymer pouches (110 mm x 120 mm), hermetically sealed by MULTIVAC C300 vacuum chamber machine, and stored in room temperature +21.0±0.5 °C. The physiochemical properties – weight losses, moisture content, hardness, pH, colour, changes of atmosphere content (CO2 and O2) in headspace of packs, and microbial conditions were analysed before packaging and in the 7th, 14th, 21st and 28th days of storage.

Keywords: Active packaging, wheat bread, shelf life.

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583 Technology, Organizational and Environmental Determinants of Business Intelligence Systems Adoption in Croatian SME: A Case Study of Medium-Sized Enterprise

Authors: Ana-Marija Stjepić, Luka Sušac, Dalia Suša Vugec

Abstract:

In the last few years, examples from scientific literature and business practices show that the adoption of technological innovations increases enterprises' performance. Recently, when it comes to the field of information technology innovation, business intelligence systems (BISs) have drawn a significant amount of attention of the scientific circles. BISs can be understood as a form of technological innovation which can bring certain benefits to the organizations that are adopting it. Therefore, the aim of this paper is twofold: (1) to define determinants of successful BISs adoption in small and medium enterprises and thus contribute to this neglected research area and (2) to present the current state of BISs adoption in small and medium-sized companies. In order to do so, determinants are defined and classified into three dimensions, according to the Technology – Organization – Environment (TOE) theoretical framework that describes the impact of each dimension on technological innovations adoption. Moreover, paper brings a case study presenting the adoption of BISs in practice within an organization from tertiary (service) industry sector. Based on the results of the study, guidelines for more efficient, faster and easier BISs adoption are presented.

Keywords: Adoption, business intelligence, business intelligence systems, case study, TOE framework.

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582 Influence of Raw Material Composition on Microstructure and Mechanical Properties of Nodular Cast Iron

Authors: Alan Vaško, Juraj Belan, Lenka Hurtalová, Eva Tillová

Abstract:

The aim of this study is to evaluate the influence of raw material composition on the microstructure, mechanical and fatigue properties and micromechanisms of failure of nodular cast iron. In order to evaluate the influence of charge composition, the structural analysis, mechanical and fatigue tests and microfractographic analysis were carried out on specimens of ten melts with different charge compositions. The basic charge of individual melts was formed by different ratio of pig iron and steel scrap and by different additive for regulation of chemical composition (silicon carbide or ferrosilicon). The results show differences in mechanical and fatigue properties, which are connected with the microstructure. SiC additive positively influences microstructure. Consequently, mechanical and fatigue properties of nodular cast iron are improved, especially in the melts with higher ratio of steel scrap in the charge.

Keywords: Nodular cast iron, silicon carbide, microstructure, mechanical properties.

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581 Visualization of Latent Sweat Fingerprints Deposit on Paper by Infrared Radiation and Blue Light

Authors: Xiaochun Huang, Xuejun Zhao, Yun Zou, Feiyu Yang, Wenbin Liu, Nan Deng, Ming Zhang, Nengbin Cai

Abstract:

A simple device termed infrared radiation (IR) was developed for rapid visualization of sweat fingerprints deposit on paper with blue light (450 nm, 11 W). In this approach, IR serves as the pretreatment device before the sweat fingerprints was illuminated by blue light. An annular blue light source was adopted for visualizing latent sweat fingerprints. Sample fingerprints were examined under various conditions after deposition, and experimental results indicate that the recovery rate of the latent sweat fingerprints is in the range of 50%-100% without chemical treatments. A mechanism for the observed visibility is proposed based on transportation and re-impregnation of fluorescer in paper at the region of water. And further exploratory experimental results gave the full support to the visible mechanism. Therefore, such a method as IR-pretreated in detecting latent fingerprints may be better for examination in the case where biological information of samples is needed for consequent testing.

Keywords: Forensic science, visualization, infrared radiation, blue light, latent sweat fingerprints, detection.

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580 Development of an Omaha System-Based Remote Intervention Program for Work-Related Musculoskeletal Disorders among Front-Line Nurses

Authors: Tianqiao Zhang, Ye Tian, Yanliang Yin, Yichao Tian, Suzhai Tian, Weige Sun, Ruoliang Tang

Abstract:

Heavy biomechanical loads at workplaces may lead to high risks of work-related musculoskeletal disorders (WMSDs). However, there is a lack of investigations on the efficacy of the ergonomic interventions with theoretical frameworks. This study aimed to formulate an Omaha System based remote intervention program on the WMSDs among nurses by systematic literature review, interviews, expert consultation. After screening title and abstract, 11 articles out of the initial search results (i.e., n=1,418) were included, 12 nurses were interviewed, and 10 experts were consulted to review the initial intervention program. Modification to the draft included (1) supplementing traditional Chinese medicine practices, (2) adding the use of assistive patient handling equipment, (3) revising the on-line training method, (4) editing and proofreading the main text of the initial program, (5) adding quizzes and exercise scales, (6) it was determined that the associated coursework should be announced promptly with multiple follow-up reminders, and (7) removing bodyweight superman exercise, and peaceful/calm meditation. In the end, the final intervention program was developed.

Keywords: Omaha System, nurses, remote intervention, musculoskeletal disease.

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579 Application of Seismic Isolators in Kutahya City Hospital Project Utilizing Double Friction Pendulum Type Devices

Authors: Kaan Yamanturk, Cihan Dogruoz

Abstract:

Seismic isolators have been utilized around the world to protect the structures, nonstructural components and contents from the damaging effects of earthquakes. In Structural Engineering, seismic isolation is used for protecting buildings and its vibration-sensitive contents from earthquakes. Seismic isolation is a passive control system that lowers effective earthquake forces by utilizing flexible bearings. One of the most significant isolation systems is seismic isolators. In this paper, double pendulum type Teflon coated seismic isolators utilized in a city hospital project by Guris Construction and Engineering Co. Inc, located in Kutahya, Turkey, have been investigated. Totally, 498 seismic isolators were applied in the project. These isolators are double friction pendulum type seismic isolation devices. The review of current practices is also examined in this study. The focus of this study is related to the application of passive seismic isolation systems for buildings as practiced in Kutahya City Hospital Project. Based on the study, the acceleration at the top floor will be 0.18 g and it will decrease 0.01 g in every floor. Therefore, seismic isolators are very important for buildings located in earthquake zones.

Keywords: Maximum considered earthquake, moment resisting frame, seismic isolator, seismic design.

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578 Failure Analysis of a Medium Duty Vehicle Leaf Spring

Authors: Gül Çevik

Abstract:

This paper summarizes the work conducted to assess the root cause of the failure of a medium commercial vehicle leaf spring failed in service. Macro- and micro-fractographic analyses by scanning electron microscope as well as material verification tests were conducted in order to understand the failure mechanisms and root cause of the failure. Findings from the fractographic analyses indicated that failure mechanism is fatigue. Crack initiation was identified to have occurred from a point on the top surface near to the front face and to the left side. Two other crack initiation points were also observed, however, these cracks did not propagate. The propagation mode of the fatigue crack revealed that the cyclic loads resulting in crack initiation and propagation were unidirectional bending. Fractographic analyses have also showed that the root cause of the fatigue crack initiation and propagation was loading the part above design stress. Material properties of the part were also verified by chemical composition analysis, microstructural analysis by optical microscopy and hardness tests.

Keywords: Leaf spring, failure analysis, fatigue, fractography.

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577 The Wider Benefits of Negotiations: Austrian Perspective on Educational Leadership as a ‘Power Game’ for Trade Unions

Authors: Rudolf Egger

Abstract:

This paper explores the relationships between the basic learning processes of leading trade union workers and their methods for coping with the changes in the life-courses of societies today. It will discuss the fragile discourse on lifelong learning in trade unions and the “production of self-techniques” to get in touch with the new economic forms. On the basis of an empirical project, different processes of the socialization of leading trade union workers will be analysed to discover the consequences of the lifelong learning discourse. The results show what competences they need to develop for the “wider benefits of negotiations”. The main challenge remains to make visible how deeply intertwined trade union learning and education are with development in an ongoing dynamic economic process, rather than a quick-fix injection of skills and information. There is a complex relationship existing between the three ‘partners’, work, learning and society forming. The author suggests that contemporary trade unions could be trendsetters who make their own learning agendas by drawing less on formal education and more on informal and non-formal learning contexts. This is in parallel with growing political and scientific consciousness of the need to arrive at new educational/vocational policies and practices.

Keywords: Lifelong learning, Trade unions, Non-formal learning, Educational/vocational policies.

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576 Structural and Computational Studies of N-[(2,6-Diethylphenyl) carbamothioyl]-2,2-diphenylacetamide, N-[(3 Ethylphenyl) carbamothioyl]-2,2-diphenylacetamide and 2,2-Diphenyl-N-{[2-(trifluoromethyl) phenyl]carbamothioyl}acetamide

Authors: Ibrahim Abdul Razak, Suhana Arshad, Nur Rafikah Razali, Azhar Abdul Rahman, Mohd Sukeri Mohd Yusof

Abstract:

Theoretical investigations are performed by DFT method of B3LYP/6-31G+(2d,p) and B3LYP/6-311G+(2d,p) basis sets for three carbonyl thiourea compounds, namely N-[(2,6-Diethylphenyl)carbamothioyl]-2,2-diphenylacetamide (Compound I), N-[(3-Ethylphenyl)carbamothioyl]-2,2-diphenylacetamide (Compound II) and 2,2-Diphenyl-N-{[2-(trifluoromethyl)phenyl]carbamothioyl}acetamide (Compound III). Theoretical calculations for bond parameters, harmonic vibration frequencies and isotropic chemical shifts are in good agreement with the experimental results. The calculated molecular vibrations show good correlation values, which are 0.998 and 0.999 with the experimental data. The energy gap for compounds I, II and III calculated at B3LYP/6-31G+(2d,p) basis set are 4.455866117, 4.297495791 and 4.313550514 eV respectively, while for B3LYP/6-311G+(2d,p) basis set the energy gap obtained are 4.453689205 (Compound I), 4.311373603 (Compound II) and 4.315727426 (Compound III) eV.

Keywords: Crystallization, DFT studies, Spectroscopic Analysis, Thiourea.

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575 Physical-Chemical Parameters of Latvian Apple Juices and Their Suitability for Cider Production

Authors: Rita Riekstina-Dolge, Zanda Kruma, Daina Karklina, Fredijs Dimins

Abstract:

Apple juice is the main raw material for cider production. In this study apple juices obtained from 14 dessert and crab variety apples grown in Latvia were investigated. For all samples soluble solids, titratable acidity, pH and sugar content were determined. Crab apples produce more dry matter, total sugar and acid content compared to the dessert apples but it depends on the apple variety. Total sugar content of crab apple juices was 1.3 to 1.8 times larger than in dessert apple juices. Titratable acidity of dessert apple juices is in the range of 4.1g L-1 to 10.83g L-1 and in crab apple juices titratable acidity is from 7.87g L-1 to 19.6g L-1. Fructose was detected as the main sugar whereas glucose level varied depending on the variety. The highest titratable acidity and content of sugars was detected in ‘Cornelia’ apples juice.

Keywords: Apple juice, hierarchical cluster analysis, sugars, titratable acidity.

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574 Choosing Local Organic Food: Consumer Motivations and Ethical Spaces

Authors: Artur Saraiva, Moritz von Schwedler, Emília Fernandes

Abstract:

In recent years, the organic sector has increased significantly. However, with the ‘conventionalization’ of these products, it has been questioned whether these products have been losing their original vision. Accordingly, this research based on 31 phenomenological interviews with committed organic consumers in urban and rural areas of Portugal, aims to analyse how ethical motivations and ecological awareness are related to organic food consumption. The content thematic analysis highlights aspects related to society and environmental concerns. On an individual level, the importance of internal coherence, peace of mind and balance that these consumers find in the consumption of local organic products was stressed. For these consumers, local organic products consumption made for significant changes in their lives, aiding in the establishment of a green identity, and involves a certain philosophy of life. This vision of an organic lifestyle is grounded in a political and ecological perspective, beyond the usual organic definition, as a ‘post-organic era’. The paper contributes to better understand how an ideological environmental discourse allows highlighting the relationship between consumers’ environmental concerns and the politics of food, resulting in a possible transition to new sustainable consumption practices.

Keywords: Organic consumption, localism, content thematic analysis, pro-environmental discourse, political consumption, Portugal.

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573 Studying the Behavior of Asphalt Mix and Their Properties in the Presence of Nano Materials

Authors: Aman Patidar, Dipankar Sarkar, Manish Pal

Abstract:

Due to rapid development, increase in the traffic load, higher traffic volume and seasonal variation in temperature, asphalt pavement shows distresses like rutting, fatigue and thermal cracking etc. because of this pavement fails during service life so that bitumen needs to be modified with some additive. In this study VG30 grade bitumen modify with addition of nanosilica with 1% to 5% (increment of 1%) by weight of bitumen. Hot mix asphalt (HMA) have higher mixing, laying and rolling temperatures which leads to higher consumption of fuel. To address this issue, a nano material named ZycoTherm which is chemical warm mix asphalt (WMA) additive is added to bitumen. Nanosilica modification (NSMB) results in the increase in stability compared to unmodified bitumen (UMB). WMA modified mix shows slightly higher stability than UMB and NSMB in a lower bitumen content. The Retained stability and tensile strength ratio (TSR) is more than 75% and 80% respectively for both mixes. Nanosilica with WMA has more resistant to temperature susceptibility, moisture susceptibility and short term aging than NSMB.

Keywords: HMA, nanosilica, NSMB, temperature, TSR, UMB, WMA.

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572 An Energy Efficient Digital Baseband for Batteryless Remote Control

Authors: Wei-Da Toh, Yuan Gao, Minkyu Je

Abstract:

In this paper, an energy efficient digital baseband circuit for piezoelectric (PE) harvester powered batteryless remote control system is presented. Pulse mode PE harvester, which provides short duration of energy, is adopted to replace conventional chemical battery in wireless remote controller. The transmitter digital baseband repeats the control command transmission once the digital circuit is initiated by the power-on-reset. A power efficient data frame format is proposed to maximize the transmission repetition time. By using the proposed frame format and receiver clock and data recovery method, the receiver baseband is able to decode the command even when the received data has 20% error. The proposed transmitter and receiver baseband are implemented using FPGA and simulation results are presented.

Keywords: Clock and Data Recovery (CDR), Correlator, Digital Baseband, Gold Code, Power-On-Reset.

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571 Manufacturing Process of a Novel Biomass Composite Inspired from Cellular Structure of Wood

Authors: Li Yongfeng, Liu Yixing, Li Jian, Li Jun

Abstract:

A novel biomass composite inspired from wood porous structure was manufactured by impregnating vinyl monomer into wood cellular structure under vacuum conditions, and initiating the monomer for in situ polymerization through a thermal treatment. The vacuum condition was studied, and the mechanical properties of the composite were also tested. SEM observation shows that polymer generated in the wood porous structure, and strongly interacted with wood matrix; and the polymer content increased with vacuum value increasing. FTIR indicates that polymer grafted onto wood matrix, resulting chemical complex between them. The rate of monomer loading increased with increasing vacuum value and time, accordance with rate of polymer loading. The compression strength and modulus of elasticity linearly increased with the increasing rate of polymer loading. Results indicate that the novel biomass composite possesses good mechanical properties capable of applying in the fields of construction, traffic and so forth.

Keywords: Biomass composite, manufacture, vinyl monomer, wood cellular structure.

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570 Distribution and Characterization of Thermal Springs in Northern Oman

Authors: Fahad Al Shidi, Reginald Victor

Abstract:

This study was conducted in Northern Oman to assess the physical and chemical characteristics of 40 thermal springs distributed in Al Hajar Mountains in northern Oman. Physical measurements of water samples were carried out in two main seasons in Oman (winter and summer 2019). Studied springs were classified into three groups based on water temperature, four groups based on water pH values and two groups based on conductivity. Ten thermal alkaline springs that originated in Ophiolite (Samail Napp) were dominated by high pH (> 11), elevated concentration of Cl- and Na+ ions, relatively low temperature and discharge ratio. Other springs in the Hajar Super Group massif recorded high concentrations of Ca2+ and SO2-4 ions controlled by rock dominance, geochemistry processes, and mineralization. There was only one spring which has brackish water with very high conductivity (5500 µs/cm) and Total Dissolved Solids and it is not suitable for irrigation purposes because of the high abundance of Na+, Cl−, and Ca2+ ions.

Keywords: Alkaline springs, geothermal, Hajar Super Group, Northern Oman, ophiolite.

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569 Study on Environmental Statement for Home Appliances at Online Stores in Japan

Authors: Syuichi Kubota, Kayoko Yamamoto

Abstract:

This study aims to identify the current situation and problems of environmental statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold at online stores in Japan, and then to suggest how to improve the situation, through a questionnaire survey conducted among businesses that operate online stores and online malls with multiple online stores. Results of the study boil down to: (1) It is found out that environmental statement for the home appliances at online stores have four problems; (i) less information on “three Rs" and “chemical substances" than the one on “energy conservation", (ii) cost for providing environmental statement, (iii) issues associated with a label and mark placement, and (iv) issues associated with energy conservation statement. (2) Improvements are suggested for each of the four problems listed above, and shown are (i) the effectiveness of, and need to promote, a label and mark placement, (ii) cost burden on buyers, and (iii) need of active efforts made by businesses and of dissemination of legal regulations to businesses.

Keywords: Home Appliances, Environmentally-FriendlyProduct, Environmental Statement, Online Store, Japan.

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568 The Motivating and Limiting Factors of Learners’ Engagement in an Online Discussion Forum

Authors: K. Durairaj, I. N. Umar

Abstract:

Lately, asynchronous discussion forum is integrated in higher educational institutions as it may increase learning process, learners’ understanding, achievement and knowledge construction. The asynchronous discussion forum is used to complement the traditional, face-to-face learning session in hybrid learning courses. However, studies have proven that students’ engagement in online forums is still unconvincing. Thus, the aim of this study is to investigate the motivating factors and obstacles that affect the learners’ engagement in asynchronous discussion forum. This study is carried out in one of the public higher educational institutions in Malaysia with 18 postgraduate students as samples. The authors have developed a 40-items questionnaire based on literature review. The results indicate several factors that have encouraged or limited students’ engagement in asynchronous discussion forum: (a) the practices or behaviors of peers, or instructors, (b) the needs for the discussions, (c) the learners’ personalities, (d) constraints in continuing the discussion forum, (e) lack of ideas, (f) the level of thoughts, (g) the level of knowledge construction, (h) technical problems, (i) time constraints and (j) misunderstanding. This study suggests some recommendations to increase the students’ engagement in online forums. Finally, based upon the findings, some implications are proposed for further research.

Keywords: Asynchronous Discussion Forum, Engagement, Factors, Motivating, Limiting.

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567 Synthesis and Characterization of Silver/Polylactide Nanocomposites

Authors: Kamyar Shameli, Mansor Bin Ahmad, Wan Md Zin Wan Yunus, Nor Azowa Ibrahim, Maryam Jokar, Majid Darroudi

Abstract:

Silver/polylactide nanocomposites (Ag/PLA-NCs) were synthesized via chemical reduction method in diphase solvent. Silver nitrate and sodium borohydride were used as a silver precursor and reducing agent in the polylactide (PLA). The properties of Ag/PLA-NCs were studied as a function of the weight percentages of silver nanoparticles (8, 16 and 32 wt% of Ag-NPs) relative to the weight of PLA. The Ag/PLA-NCs were characterized by Xray diffraction (XRD), transmission electron microscopy (TEM), electro-optical microscopy (EOM), UV-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FT-IR). XRD patterns confirmed that Ag-NPs crystallographic planes were face centered cubic (fcc) type. TEM images showed that mean diameters of Ag-NPs were 3.30, 3.80 and 4.80 nm. Electro-optical microscopy revealed excellent dispersion and interaction between Ag-NPs and PLA films. The generation of silver nanoparticles was confirmed from the UVvisible spectra. FT-IR spectra showed that there were no significant differences between PLA and Ag/PLA-NCs films. The synthesized Ag/PLA-NCs were stable in organic solution over a long period of time without sign of precipitation.

Keywords: Nanocomposites, Polylactide, Silver Nanoparticles, Sodium Borohydride, Transmission Electron Microscopy.

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566 Simulating Laboratory Short Term Aging to Suit Malaysian Field Conditions

Authors: Meor O. Hamzah, Seyed R. Omranian, Ali Jamshidi, Mohd R M. Hasan

Abstract:

This paper characterizes the effects of artificial short term aging in the laboratory on the rheological properties of virgin 80/100 penetration grade asphalt binder. After several years in service, asphalt mixture started to deteriorate due to aging. Aging is a complex physico-chemical phenomenon that influences asphalt binder rheological properties causing a deterioration in asphalt mixture performance. To ascertain asphalt binder aging effects, the virgin, artificially aged and extracted asphalt binder were tested via the Rolling Thin film Oven (RTFO), Dynamic Shear Rheometer (DSR) and Rotational Viscometer (RV). A comparative study between laboratory and field aging conditions were also carried out. The results showed that the specimens conditioned for 85 minutes inside the RTFO was insufficient to simulate the actual short term aging caused that took place in the field under Malaysian field conditions

Keywords: Asphalt binder, Short term aging, Rheological properties, Viscosity, Temperature susceptibility.

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565 Effects of Thermal Radiation on Mixed Convection in a MHD Nanofluid Flow over a Stretching Sheet Using a Spectral Relaxation Method

Authors: Nageeb A. H. Haroun, Sabyasachi Mondal, Precious Sibanda

Abstract:

The effects of thermal radiation, Soret and Dufour parameters on mixed convection and nanofluid flow over a stretching sheet in the presence of a magnetic field are investigated. The flow is subject to temperature dependent viscosity and a chemical reaction parameter. It is assumed that the nanoparticle volume fraction at the wall may be actively controlled. The physical problem is modelled using systems of nonlinear differential equations which have been solved numerically using a spectral relaxation method. In addition to the discussion on heat and mass transfer processes, the velocity, nanoparticles volume fraction profiles as well as the skin friction coefficient are determined for different important physical parameters. A comparison of current findings with previously published results for some special cases of the problem shows an excellent agreement.

Keywords: Non-isothermal wedge, thermal radiation, nanofluid, magnetic field, Soret and Dufour effects.

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564 Socio-Technical Systems: Transforming Theory into Practice

Authors: L. Ngowi, N. H. Mvungi

Abstract:

This paper critically examines the evolution of socio-technical systems theory, its practices, and challenges in system design and development. It examines concepts put forward by researchers focusing on the application of the theory in software engineering. There are various methods developed that use socio-technical concepts based on systems engineering without remarkable success. The main constraint is the large amount of data and inefficient techniques used in the application of the concepts in system engineering for developing time-bound systems and within a limited/controlled budget. This paper critically examines each of the methods, highlight bottlenecks and suggest the way forward. Since socio-technical systems theory only explains what to do, but not how doing it, hence engineers are not using the concept to save time, costs and reduce risks associated with new frameworks. Hence, a new framework, which can be considered as a practical approach is proposed that borrows concepts from soft systems method, agile systems development and object-oriented analysis and design to bridge the gap between theory and practice. The approach will enable the development of systems using socio-technical systems theory to attract/enable the system engineers/software developers to use socio-technical systems theory in building worthwhile information systems to avoid fragilities and hostilities in the work environment.

Keywords: Socio-technical systems, human centered design, software engineering, cognitive engineering, soft systems, systems engineering.

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563 Quality Function Deployment Application in Sewer Pipeline Assessment

Authors: Khalid Kaddoura, Tarek Zayed

Abstract:

Infrastructure assets are essential in urban cities; their purpose is to facilitate the public needs. As a result, their conditions and states shall always be monitored to avoid any sudden malfunction. Sewer systems, one of the assets, are an essential part of the underground infrastructure as they transfer sewer medium to designated areas. However, their conditions are subject to deterioration due to ageing. Therefore, it is of great significance to assess the conditions of pipelines to avoid sudden collapses. Current practices of sewer pipeline assessment rely on industrial protocols that consider distinct defects and grades to conclude the limited average or peak score of the assessed assets. This research aims to enhance the evaluation by integrating the Quality Function Deployment (QFD) and the Decision-Making Trial and Evaluation Laboratory (DEMATEL) methods in assessing the condition of sewer pipelines. The methodology shall study the cause and effect relationship of the systems’ defects to deduce the relative influence weights of each defect. Subsequently, the overall grade is calculated by aggregating the WHAT’s and HOW’s of the House of Quality (HOQ) using the computed relative weights. Thus, this study shall enhance the evaluation of the assets to conclude informative rehabilitation and maintenance plans for decision makers.

Keywords: Condition assessment, DEMATEL, QFD, sewer pipelines.

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562 Impact of Gold and Silver Nanoparticles on Terrestrial Flora and Microorganisms

Authors: L. Steponavičiūtė, L. Steponavičienė

Abstract:

Despite the rapid nanotechnology progress and recognition, its potential impact in ecosystems and health of humans is still not fully known. In this paper, the study of ecotoxicological dangers of nanomaterials is presented. By chemical reduction method, silver (AgNPs) and gold (AuNPs) nanoparticles were synthesized, characterized and used in experiments to examine their impact on microorganisms (Escherichia coli, Staphylococcus aureus and Candida albicans) and terrestrial flora (Phaseolus vulgaris and Lepidium sativum). The results collected during experiments with terrestrial flora show tendentious growth stimulations caused by gold nanoparticles. In contrast to these results, silver nanoparticle solutions inhibited growth of beans and garden cress, compared to control samples. The results obtained from experiments with microorganisms show similarities with ones collected from experiments with terrestrial plants. Samples treated with AuNPs of size 13 nm showed stimulation in the growth of the colonies compared with 3,5 nm size nanoparticles.

Keywords: Ecosystems, ecotoxicology, nanomaterials, nanoparticles.

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561 The Folksongs of Jharkhand: An Intangible Cultural Heritage of Tribal India

Authors: Walter Beck

Abstract:

Jharkhand is newly constituted 28th State in the eastern part of India which is known for the oldest settlement of the indigenous people. In the State of Jharkhand in which broadly three language family are found namely, Austric, Dravidian, and Indo-European. Ex-Mundari, kharia, Ho Santali come from the Austric Language family. Kurukh, Malto under Dravidian language family and Nagpuri Khorta etc. under Indo-European language family. There are 32 Indigenous Communities identified as Scheduled Tribe in the State of Jharkhand. Santhal, Munda, Kahria, Ho and Oraons are some of the major Tribe of the Jharkhand state. Jharkhand has a Rich Cultural heritage which includes Folk art, folklore, Folk Dance, Folk Music, Folk Songs for which diversity can been seen from place to place, season to season and all traditional Culture and practices. The languages as well as the songs are vulnerable to dominant culture and hence needed to be protected. The collection and documentation of these songs in their natural setting adds significant contribution to the conservation and propagation of the cultural elements. This paper reflects to bring out the Originality of the Collected Songs from remote areas of the plateau of Sothern Jharkhand as a rich intangible Cultural heritage of the Country. The research was done through participatory observation. In this research project more than 100 songs which were never documented before.

Keywords: Cultural heritage, India, Indigenous people, songs.

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560 Carbon Disulfide Production via Hydrogen Sulfide Methane Reformation

Authors: H. Hosseini, M. Javadi, M. Moghiman, M. H. Ghodsi Rad

Abstract:

Carbon disulfide is widely used for the production of viscose rayon, rubber, and other organic materials and it is a feedstock for the synthesis of sulfuric acid. The objective of this paper is to analyze possibilities for efficient production of CS2 from sour natural gas reformation (H2SMR) (2H2S+CH4 =CS2 +4H2) . Also, the effect of H2S to CH4 feed ratio and reaction temperature on carbon disulfide production is investigated numerically in a reforming reactor. The chemical reaction model is based on an assumed Probability Density Function (PDF) parameterized by the mean and variance of mixture fraction and β-PDF shape. The results show that the major factors influencing CS2 production are reactor temperature. The yield of carbon disulfide increases with increasing H2S to CH4 feed gas ratio (H2S/CH4≤4). Also the yield of C(s) increases with increasing temperature until the temperature reaches to 1000°K, and then due to increase of CS2 production and consumption of C(s), yield of C(s) drops with further increase in the temperature. The predicted CH4 and H2S conversion and yield of carbon disulfide are in good agreement with result of Huang and TRaissi.

Keywords: Carbon disulfide, sour natural gas, H2SMR, probability density function.

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559 Different Formula of Mixed Bacteria as a Bio-Treatment for Sewage Wastewater

Authors: E. Marei, A. Hammad, S. Ismail, A. El-Gindy

Abstract:

This study aims to investigate the ability of different formula of mixed bacteria as a biological treatments of wastewater after primary treatment as a bio-treatment and bio-removal and bio-adsorbent of different heavy metals in natural circumstances. The wastewater was collected from Sarpium forest site-Ismailia Governorate, Egypt. These treatments were mixture of free cells and mixture of immobilized cells of different bacteria. These different formulas of mixed bacteria were prepared under Lab. condition. The obtained data indicated that, as a result of wastewater bio-treatment, the removal rate was found to be 76.92 and 76.70% for biological oxygen demand, 79.78 and 71.07% for chemical oxygen demand, 32.45 and 36.84 % for ammonia nitrogen as well as 91.67 and 50.0% for phosphate after 24 and 28 hrs with mixed free cells and mixed immobilized cells, respectively. Moreover, the bio-removals of different heavy metals were found to reach 90.0 and 50. 0% for Cu ion, 98.0 and 98.5% for Fe ion, 97.0 and 99.3% for Mn ion, 90.0 and 90.0% Pb, 80.0% and 75.0% for Zn ion after 24 and 28 hrs with mixed free cells and mixed immobilized cells, respectively. The results indicated that 13.86 and 17.43% of removal efficiency and reduction of total dissolved solids were achieved after 24 and 28 hrs with mixed free cells and mixed immobilized cells, respectively.

Keywords: Biological desalination, bio-sorption heavy metals, free cell bacteria, immobilized bacteria, wastewater bio-treatment.

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558 Religion and Sustainable Development: A Comparative Study of Buddhist and Christian Farmers’ Contribution to the Environmental Protection in Taiwan

Authors: Jijimon Alakkalam Joseph

Abstract:

The UN 2030 Agenda for Sustainable Development claims to be a comprehensive and integrated plan of action for prosperity for people and the planet, including almost all dimensions of human existence. Nevertheless, the religious dimension of human existence has been kept away from development discussions. Care for the earth is one of the vital aspects of sustainable development. Farmers all over the world contribute much to environmental protection. Most farmers are religious believers and religious ideologies influence their agricultural practices. This nexus between faith and agriculture has forced policymakers to include religion in development discussions. This paper delves deeper into this religion and sustainable development connection. Buddhism and Christianity have contributed much to environmental protection in Taiwan. However, interviews conducted among 40 Taiwanese farmers (10 male and female farmers from Buddhism and Christianity) show that their faith experiences make them relate to the natural environment differently. Most of the Buddhist farmers interviewed admitted that they chose their religious adherence, while most of the Christian farmers inherited their faith. The in-depth analysis of the interview data collected underlines the close relationship between religion and sustainable development. More importantly, concerning their intention to care for the earth, farmers whose religious adherence is ‘chosen’ are self-motivated and more robust compared to those whose religious adherence is ‘inherited’.

Keywords: Buddhism, Christianity, environmental protection, sustainable development.

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