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61.
Discharge of Green House Gases (GHGs) and the management of municipal solid waste (MSW) continue to be a major challenge particularly in growing economies. However, these are resources which can be converted to green energy. Landfill gas which is essentially methane (50–55%) and carbon dioxide (40–45%) (both GHGs) is released from MSW by biodegradation processes. The estimation of this methane and its economic and environmental benefits for environmental sustainability are the objectives of this study. Methane emission from MSW disposed of in landfills was estimated using Intergovernmental Panel on Climate Change (IPCC) methodology. From the study, based on 8,196,000 tonnes MSW generated in Peninsular Malaysia in 2010, anthropogenic methane emission of about 310,220 tonnes per year was estimated. This was estimated to generate 1.9 billion kWh of electricity year?1 worth over RM 570 million (US$190 million). In addition, this leads to carbon dioxide reduction of 6,514,620 tonnes year?1 equivalent to carbon credit of over RM 257 million (US$85 million). These results were also projected for 2015 and 2020 and the outcomes are promising. Therefore, the exploration of this resource, besides the economic benefits helps in reducing the dependence on the depleting fossil fuel and hence broadening the fuel base of the country.  相似文献   
62.
The evolution of new SARS-CoV-2 variants around the globe has made the COVID-19 pandemic more worrisome, further pressuring the health care system and immunity. Novel variations that are unique to the receptor-binding motif (RBM) of the receptor-binding domain (RBD) spike glycoprotein, i. e. L452R-E484Q, may play a different role in the B.1.617 (also known as G/452R.V3) variant's pathogenicity and better survival compared to the wild type. Therefore, a thorough analysis is needed to understand the impact of these mutations on binding with host receptor (RBD) and to guide new therapeutics development. In this study, we used structural and biomolecular simulation techniques to explore the impact of specific mutations (L452R-E484Q) in the B.1.617 variant on the binding of RBD to the host receptor ACE2. Our analysis revealed that the B.1.617 variant possesses different dynamic behaviours by altering dynamic-stability, residual flexibility and structural compactness. Moreover, the new variant had altered the bonding network and structural-dynamics properties significantly. MM/GBSA technique was used, which further established the binding differences between the wild type and B.1.617 variant. In conclusion, this study provides a strong impetus to develop novel drugs against the new SARS-CoV-2 variants.  相似文献   
63.
Protection of Metals and Physical Chemistry of Surfaces - In situ direct formation of titanium carbide (TiC) was realized via tungsten inert gas (TIG) arc surface cladding using titanium dioxide...  相似文献   
64.
The catalyst has a significant role in gas processing applications such as reforming technologies for H2 and syngas production. The stable catalyst is requisite for any industrial catalysis application to make it commercially viable. Several methods are employed to synthesize the catalysts. However, there is still a challenge to achieve a controlled morphology and pure catalyst which majorly influences the catalytic activity in reforming applications. The conventional methods are expansive, and the removal of the impurities are major challenges. Nevertheless, it is not straightforward to achieve the desired structure and stability. Therefore, significant interest has been developed on the advanced techniques to take control of the physicochemical properties of the catalyst through non-thermal plasma (NTP) techniques. In this review, the systematic evolution of the catalyst synthesis using NTP technique is elucidated. The emerging DBD plasma to synthesized and effective surface treatment is reviewed. DBD plasma synthesized catalyst performance in reforming application for H2 and syngas production is summarised. Furthermore, the status of DBD plasma for catalyst synthesis and proposed future avenues to design environmentally suitable and cost-effective synthesis techniques are discussed.  相似文献   
65.
The extraction of heavy metals from industrial effluents using efficient adsorbents is crucial for wastewater treatment and beneficial for metal recycling. In this study, the removal of Cu(II) from an acidic solution by commercial resins Dowex G-26 and Puromet™ MTS9570 was investigated. The influences of contact time, solution concentration, pH, temperature, and a resin dosage on the adsorption process were studied with batch technique. The optimum adsorption conditions were obtained at a concentration of 1100 mg/L Cu, contact time of 30 min, pH 3.5, and resin dosage of 0.025 g/ml for the removal of 99.9% and 90% of copper ions by G-26 and MTS9570, respectively. The experimental data of copper adsorption were analyzed using the Langmuir, Freundlich, and Temkin isotherm models. The highest metal uptakes of 41.67 and 37.70 mg/g were observed for Dowex G-26 and MTS9570, respectively. It was found that both resins had higher adsorption capacities than the substances reported in the literature. The adsorption kinetic studies showed that the copper adsorption process could be better described by the pseudo-second order model. Adsorption occurs spontaneously under endothermic conditions, which indicates the endothermic nature of the process.  相似文献   
66.
Education quality has undoubtedly become an important local and international benchmark for education, and an institute’s ranking is assessed based on the quality of education, research projects, theses, and dissertations, which has always been controversial. Hence, this research paper is influenced by the institutes ranking all over the world. The data of institutes are obtained through Google Scholar (GS), as input to investigate the United Kingdom’s Research Excellence Framework (UK-REF) process. For this purpose, the current research used a Bespoke Program to evaluate the institutes’ ranking based on their source. The bespoke program requires changes to improve the results by addressing these methodological issues: Firstly, Redundant profiles, which increased their citation and rank to produce false results. Secondly, the exclusion of theses and dissertation documents to retrieve the actual publications to count for citations. Thirdly, the elimination of falsely owned articles from scholars’ profiles. To accomplish this task, the experimental design referred to collecting data from 120 UK-REF institutes and GS for the present year to enhance its correlation analysis in this new evaluation. The data extracted from GS is processed into structured data, and afterward, it is utilized to generate statistical computations of citations’ analysis that contribute to the ranking based on their citations. The research promoted the predictive approach of correlational research. Furthermore, experimental evaluation reported encouraging results in comparison to the previous modification made by the proposed taxonomy. This paper discussed the limitations of the current evaluation and suggested the potential paths to improve the research impact algorithm.  相似文献   
67.
The melting and crystallization behaviours of a polyethylene‐block‐poly(methyl methacrylate) (PE‐b‐PMMA) diblock copolymer and a PE homopolymer were investigated using multiple heating and cooling rate differential scanning calorimetry (DSC) experiments, and modelling of the crystallization kinetics and lamellar thickness distribution. This new model was first validated applying literature and experimental data. The model‐predicted morphology (n = 3.2) closely matched the spherulitic morphology (n = 3), which was determined using polarized optical microscopy. For each experimental cooling rate, the model predicted diblock copolymer crystallinity that well matched the entire DSC crystallinity curve, notably for an Avrami–Erofeev index of n = 2; and apparent crystallization activation energy that hardly varied with the cooling rates used, relative crystallinity (α), and crystallization temperature or time. This disfavours the concept of variable activation energy. The use of the right crystallization model and parameter estimation algorithm is important for addressing the mathematical artefact. Under non‐isothermal cooling, the PE‐b‐PMMA diblock copolymer, as per the model prediction, crystallized without confinement (n ≠ 1), preserving the cylindrical structure. From the characteristic shapes of the crystallization function f(α(T)) versus 1/T and crystallization rate versus α plots, the resulting Tcmax and narrow αmax range can guide the search for an appropriate crystallization model. The overall treatment illustrated in this study is not restricted to a PE homopolymer and a PE‐b‐isotactic PMMA block copolymer. It can be generally applied to crystalline homopolymers and copolymers (alternating, random and block), as well as their blends. The block copolymers and blends can be crystalline–amorphous as well as crystalline–crystalline. © 2014 Society of Chemical Industry  相似文献   
68.
Model Based System Engineering (MBSE) is a renowned approach in the context of embedded systems development. It is frequently used to deal with the structural and behavioral aspects of system design. However, the verification of system design is generally performed in isolation. It is particularly true in the context of assertion based verification. Consequently, there is a huge gap between system design and its verification that seriously effects the productivity and time-to market objectives. Therefore, in this research, we target to reduce this gap by exploiting the features of MBSE and SystemVerilog assertions (SVA’s). This article introduces a novel MBSE approach to model the design verification aspects of embedded systems, along with the system design (structural and behavioral aspects). We propose SystemVerilog in Object Constraint Language (SVOCL), an OCL temporal extension for SystemVerilog, to represent the design verification requirements by means of SVA’s. As a part of research, SVOCL transformation engine has been developed to generate SVA’s code in order to automate the design verification of embedded systems. The application of SVOCL has been validated through four case studies.  相似文献   
69.
In this paper, the performance of uncoded uplink transmissions in a broadband code division multiple access (CDMA) system using tapped delay line (TDL) antenna array under multipath conditions is investigated. An expression for broadband CDMA system is derived to calculate the optimal weights of TDL antenna array. Using the derived broadband expression, the performance of TDL antenna array is investigated and compared with that of the already existing narrowband systems. Simulation results show that TDL antenna array can reduce multipath fading and multiple access interference (MAI). It is shown that if the signal‐to‐noise ratio (SNR) level is maintained at 20 dB and two‐ray channel model is used, two antennas with four taps each can support 30 users with a BER of 10?3. If three‐ray channel model is used, the same antenna arrangement is not enough to support 30 users. To support these 30 users with BER of 10?3, the number of taps needs to be increased to eight. Finally, the number of taps needs to be further increased to 16 if four‐ray channel model is used. Not only that, the SNR should also be increased to 25 dB to achieve the same BER. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
70.
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