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1.
Hydrothermally prepared zinc oxide nanorods are sulphonated (S–ZnO NR) and incorporated into 15% Sulphonated Poly (1,4-Phenylene Ether Ether Sulfone) (SPEES) to improve the hydrophilicity, water uptake and ion transfer capacity. Water uptake and ion transfer capacity increased to 34.6 ± 0.6% and 2.0 ± 0.05 meq g?1 from 29.8 ± 0.3% and 1.4 ± 0.04 meq g?1 by adding 7.5 wt% S–ZnO NR to SPEES. Morphological studies show the prepared S–ZnO NR is well dispersed in the polymer matrix. SPEES +7.5 wt% S–ZnO NR membrane exhibits optimum performance after three-weeks of continual operation in a fabricated microbial fuel cell (MFC) to produce a maximum power density of 142 ± 1.2 mW m?2 with a reduced biofilm compared to plain SPEES (59 ± 0.8 mW m?2), unsulphonated filler incorporated SPEES (SPEES + 7.5 wt% ZnO, 68 ± 1.1 mW m?2) and Nafion (130 ± 1.5 mW m?2) thereby suggesting its suitability as a sustainable and improved cation exchange membrane (CEM) for MFCs.  相似文献   
2.
Experiments have been carried out to evaluate the onset of wrinkling behaviour in three grades of annealed commercial aluminium sheets namely ISS 19000, ISS 19600 and ISS 19660 having thickness 2.00 mm, while drawing them through a conical die. The deep drawing of circular blanks of different diameters of the aforesaid sheet metals was carried out using flat bottom punch. The analysis of the experimental data has revealed that the onset of wrinkling takes place when the ratio of the plastic strain increments (dεr/dεθ) reached a critical value. It was further found that the measured strains followed non-linear paths in the wrinkling limit diagrams. Further, it was observed that the aluminium grade having high strain hardening index value, low yield stress and high normalized hardening rate shows better resistance against wrinkling. Furnace cooled aluminium grades showed better resistance against wrinkling compared with air cooled blanks.  相似文献   
3.
Design of industrial annealing cycles requires recrystallization and grain growth studies, which are typically carried out under isothermal laboratory condition. The kinetics coefficients of these phase transformations are obtained from such studies, which are subsequently used in designing the industrial nonisothermal cycles using the additivity principles. However, the strong heating rate effects on the grain growth kinetics necessitate such kinetics studies using industrial thermal profiles. In the present work, the hot and cold spot cycles of an industrial batch annealing cycle for AIK grade steel have been simulated in a programmable laboratory furnace. Subsequently, the effect of annealing temperature, soaking time, and heating rate on the microstructural features, such as grain size distribution, grain shape anisotropy, and grain orientation, have been investigated through extensive quantitative microscopy. The implications of these results on the design of industrial batch annealing cycles have been discussed.  相似文献   
4.
This paper investigates the performance of a dual-hop mixed relay system with radio frequency (RF) and free-space optics (FSO) communication under the effect of pointing error (PE) and atmospheric turbulence (AT). This paper considers a system where RF and FSO links are cascaded. The RF link is modeled by Nakagami-m fading, and the FSO link is modeled as gamma–gamma (G-G) fading channel. Both the channel models use orthogonal frequency division multiplexing (OFDM) with M-ary quadrature amplitude modulation (QAM). The expressions for probability density function, cumulative distribution function, signal-to-noise ratio, and ergodic capacity are derived. The moment generating function (MGF) of fading and the bit error rate (BER) of the OFDM-based M-ary QAM scheme is derived in terms of Meijer's G-function. It has been observed that, in fixed gain relay systems, the modulation scheme's BER is dominated by the SNR of the RF link. While in a variable gain relay system, the turbulence conditions of the FSO system affect the SNR and the BER of the modulation method. The feasibility of heterodyne detection and intensity modulation direct detection (IM/DD) is analyzed in terms of outage probability and ergodic capacity. The results can be used to choose the optimal modulation order and relay system for QAM-OFDM-based optical wireless systems.  相似文献   
5.

Domestic fund transfers are all the time immediate, handier and obtainable however in overseas fund transfer, funds are transferred from payers account to payees account through the correspondent banks, central bank and messaging network which involves intermediaries and allied charges. Blockchain Technology has grabbed the interest of financial systems due to its inventive benefits such as decentralised structure, faster speed, cost-effectiveness and more security over conventional approaches. Adopting Blockchain Technology for overseas fund transfer can overcome the transaction delays, intermediaries’ failures and recurring costs involved in the current system. In this paper, a Consortium Blockchain based overseas fund transfer process is proposed to achieve faster operations, security and transparency. Hyperledger Fabric Blockchain framework has been used for overseas fund transfer process and web-user interface is developed for the same. Simulation results demonstrate the significance of Blockchain as a promising technology for overseas fund transfer process to facilitate speed, security, transparency and efficiency for overseas fund transfer.

  相似文献   
6.
Technological advancement has brought a whole new way of delivering financial services around the world. E-finance industry in Malaysia has grown rapidly with the help of internet and conducting financial services are far easier now if compared to last time. Internet provided a new medium or channel in delivering financial services. However, there are also risks and challenges when using electronic finance. A total of 100 respondents had been targeted in completing this study. Survey method was utilized in collecting respondent’s opinion and perception to test the variables. The target was companies which used electronic finance in delivering their services. Interviews were also conducted and relevant tests conducted which provided evidence to support the hypotheses for this study. It was found that e-finance was affected by security, revenue and cost dimensions, and technology architecture with the adoption of global technology.  相似文献   
7.
Educational institutions showing interest to find the opinion of the students about their course and the instructors to enhance the teaching-learning process. For this, most research uses sentiment analysis to track students’ behavior. Traditional sentence-level sentiment analysis focuses on the whole sentence sentiment. Previous studies show that the sentiments alone are not enough to observe the feeling of the students because different words express different sentiments in a sentence. There is a need to extract the targets in a given sentence which helps to find the sentiment towards those targets. Target extraction is the subtask of targeted sentiment analysis. In this paper, we proposed the innovative model to find the targets of the given sentence using Bi-Integrated Conditional Random Fields (CRF). A Parallel fusion neural network model is designed to perform this task. We evaluate the model using the Michigan dataset and we build a dataset for target extraction from student reviews. The experimental results show that our proposed fusion model achieves better results compared to baseline models.  相似文献   
8.
Ta‐doped cubic phase Li7La3Zr2O12 (LLZ) lithium garnet received considerable attention in recent times as prospective electrolyte for all‐solid‐state lithium battery. Although the conductivity has been improved by stabilizing the cubic phase with the Ta5+ doping for Zr4+ in LLZ, the density of the pellet was found to be relatively poor with large amount of pores. In addition to the high Li+ conductivity, density is also an essential parameter for the successful application of LLZ as solid electrolyte membrane in all‐solid‐state lithium battery. Systematic investigations carried out through this work indicated that the optimal Li concentration of 6.4 (i.e., Li6.4La3Zr1.4Ta0.6O12) is required to obtain phase pure, relatively dense and high Li+ conductive cubic phase in Li7?xLa3Zr2?xTaxO12 solid solutions. Effort has been also made in this work to enhance the density and Li+ conductivity of Li6.4La3Zr1.4Ta0.6O12 further through the Li4SiO4 addition. A maximized room‐temperature (33°C) total (bulk + grain boundary) Li+ conductivity of 3.7 × 10?4 S/cm and maximized relative density of 94% was observed for Li6.4La3Zr1.4Ta0.6O12 added with 1 wt% of Li4SiO4.  相似文献   
9.
10.
Abstract

We report, here, the corrosion inhibition of mild steel specimen in 1?M HCl by tamarind fruit pulp aqueous (TFPA) extract. The inhibition property in the presence of TFPA extract is studied using weight loss, polarization measurement and electrochemical impedance spectroscopy (EIS). The inhibitor efficiency is found to vary from 74% to 88% (weight loss method) with TFPA concentration of 100–600?ppm. The reduction in Tafel slopes shows that TFPA acts as a mixed-type inhibitor. The adsorption of the inhibitor on the metal surface follows Langmuir isotherm. The standard Gibbs free energy of adsorption value of –40?kJ/mol suggests the chemisorption of inhibitor molecules via coordinate bond. AFM results exhibit a decrease in the surface roughness of mild steel, exposed to 1?M HCl from 299?±?12 to 154?±?6.6?nm, with increasing concentration of inhibitor from 0 to 600?ppm due to the uniform coverage of inhibitor molecules on the metal surface. X-ray photoelectron spectroscopy de-convoluted high resolution profiles of C 1?s (carbon) for mild steel exposed to 1?M HCl with 600?ppm inhibitor show major peaks corresponding to sp3 C–C/C–H (284.9?eV) and oxygen bondings in C–OH, C=O, COOH with a binding energy of 285.9, 286.9, 288.5?eV, respectively, thereby confirming the adsorption of organic moieties on mild steel surface. Fourier transform infrared spectroscopy further confirms the adsorption of inhibitor molecules on the metal surface. Therefore, tamarind fruit pulp extract is a potential corrosion inhibitor for mild steel, which is cost-effective, green and non-toxic.  相似文献   
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