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171.
Ufana Riaz S.M. Ashraf Jyoti Kashyap 《Polymer-Plastics Technology and Engineering》2015,54(17):1850-1870
Research in the field of TiO2-based photocatalysis has gained wide attention to address important energy and environmental problem. Lately, the use of conducting polymers as photosensitizers has proven to immensely enhance photodegradation by exhibiting excellent photocatalytic activity under both ultraviolet light and natural sunlight irradiation which is not possible using semiconductors alone. Considering the unique performance of conducting polymer-based nanocomposites in photocatalysis, the present review provides the recent advances in the development of ultraviolet and visible light-responsive conducting polymer-based TiO2 nanocomposites for their potential application in environmental remediation. This review ends with a summary focusing on the challenges and new dimensions in this still emerging area of research. 相似文献
172.
173.
During present investigations, an attempt was made to understand the effect of mean stress and oxidation on low cycle fatigue (LCF) behaviour of CM 247 DS LC alloy at T?=?850°C. A significant reduction in fatigue life was observed during LCF tests conducted at strain ratio (R) of 0 as compared to R?=??1. Reduction in fatigue life is attributed to the synergistic effect of mean stress, oxidation and the expanding precipitates within the grain boundaries which imparts high stresses at the grain boundary leading to the intergranular cracking. Additionally, to account the effect of mean stress on fatigue life of the alloy CM 247 DS LC empirical relations developed by Smith–Watson–Topper (SWT) and Morrow were used. 相似文献
174.
Development of templated carbon by carbonisation of sucrose–zeolite composite for hydrogen storage 下载免费PDF全文
The templated carbons were synthesised by carbonisation of a zeolite–sucrose composite. The effects of carbonisation temperature and dwelling time on the development of pore structure of templated carbon were investigated. Various characterisation techniques were employed to investigate the structural and topographical properties of template precursor as well as synthesised carbons. The highest total surface area of 1033 m2/g and micropore area of 647 m2/g were obtained for carbon synthesised at 750°C with 3 h dwelling time. It was observed that at lower carbonisation temperature or dwelling time, the surface area and pore volume were lower, which may be attributed to incomplete carbonisation of the sucrose. At higher carbonisation temperature or dwelling time, the decrease in surface area and pore volume could be the result of collapse of the pore structure. Maximum 80% micropore area was observed for the templated carbons depending on the synthesis conditions. The hydrogen uptake of the templated carbons was measured by temperature‐programmed desorption at 1 bar pressure and different subzero temperatures. The maximum uptake (0.30 wt%) was obtained at 1 bar and ?100°C for templated carbon, having a surface area of 1033 m2/g, prepared at 750°C with 3 h dwelling time. This templated carbon had the highest total surface area as well as micropore area. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
175.
An efficient drain current simulation model for the electron irradiation effect on the electrical parameters of amorphous In-Ga-Zn-O (IGZO) thin-film transistors is developed.The model is developed based on the specifications such as gate capacitance,channel length,channel width,flat band voltage etc.Electrical parameters of un-irradiated IGZO samples were simulated and compared with the experimental parameters and 1 kGy electron irradiated parameters.The effect of electron irradiation on the IGZO sample was analysed by developing a mathematical model. 相似文献
176.
A modified endoscopic technique for anterior cruciate ligament (ACL) reconstruction using an autologous patellar tendon graft is described using the early results for 120 patients. A special technique using an oscillating hollow saw allows for the rapid and standardized harvest of cylindrical bone plugs, ensuring safe and adequate femoral press-fit fixation. The complications encountered included one fracture of a bone back on plugging in as well as two cases with revision procedures for interference screw fixation due to insufficient femoral anchorage. Within the framework of a prospective study, all 120 patients underwent a control arthroscopy after the first postoperative year showing viable and mechanically stable grafts in 64 (53.3%) of the patients. In 44 patients (36.7%), viable though somewhat lax grafts were found, whereas the remaining 12 patients (10%) only showed insufficient tissue residues. All of these cases were the result of a ventral misplacement of the femoral insertion site representing the primary complication of transtibial technique. The results of the control arthroscopies showed a highly significant correlation with the clinical results for the IKDC score obtained in a follow-up after an average 29 (18 to 36) months. The results for stability according to the IKDC rating scale showed a normal or near-normal knee function in 76.7%. With regard to the subjective results in the IKDC rating scale, 83.3% of the patients (n = 100) assessed their knee function as normal or almost normal. The location and positioning of the femoral and tibial tunnel were evaluated in an exact radiographic evaluation showing an "ideal position" of the graft in only 94 cases (78.3%). Statistically, a significant correlation of stability with the femoral fixation site could be shown. 相似文献
177.
Studies on a novel composition of magnesium ion conducting gel polymer electrolyte (GPE), comprising a solution of Mg-salt, magnesium trifluoromethanesulfonate (Mg-triflate or \(\hbox {Mg(Tf)}_{2})\) in a plastic crystal succinonitrile (SN), entrapped in a host polymer poly(vinylidenefluoride–hexafluoropropylene) (PVdF–HFP) was reported. Small amount of an ionic liquid, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMITf) was added to stabilize the GPE composition. The electrolyte possesses excellent dimensional integrity in the form of free-standing thick film, which offers the ionic conductivity of \(4 \times 10^{-3} \hbox { S } \hbox {cm}^{-1}\) at room temperature \({\sim }26{^{\circ }}\hbox {C}\). The electrochemical potential window of the electrolyte, observed from the linear sweep voltammetry, is determined to be \({\sim }4.1 \hbox { V}\). The magnesium ion conduction in the GPE film is confirmed from cyclic voltammetry, electrochemical impedance spectroscopy and dc polarization techniques. Different structural, thermal and electrochemical studies demonstrate the promising characteristics of the polymer film, suitable as electrolyte in rechargeable magnesium batteries. The potential of the GPE as electrolyte/separator was ascertained by fabricating a prototype magnesium battery of the configuration Mg:graphite composite \(\hbox {anode}/\hbox {GPE}/\hbox {MnO}_{2}\)-cathode. The specific discharge capacity of \(40 \hbox { mAh g}^{-1}\) (with respect to the \(\hbox {MnO}_{2}\) cathode material) was obtained at the first discharge. The cell shows charge–discharge performance for eight cycles with a substantial fading in capacity. 相似文献
178.
Indrajeet Kumar Sultan S. Alshamrani Abhishek Kumar Jyoti Rawat Kamred Udham Singh Mamoon Rashid Ahmed Saeed AlGhamdi 《计算机、材料和连续体(英文)》2022,70(1):451-468
Early diagnosis of a pandemic disease like COVID-19 can help deal with a dire situation and help radiologists and other experts manage human resources more effectively. In a recent pandemic, laboratories perform diagnostics manually, which requires a lot of time and expertise of the laboratorial technicians to yield accurate results. Moreover, the cost of kits is high, and well-equipped labs are needed to perform this test. Therefore, other means of diagnosis is highly desirable. Radiography is one of the existing methods that finds its use in the diagnosis of COVID-19. The radiography observes change in Computed Tomography (CT) chest images of patients, developing a deep learning-based method to extract graphical features which are used for automated diagnosis of the disease ahead of laboratory-based testing. The proposed work suggests an Artificial Intelligence (AI) based technique for rapid diagnosis of COVID-19 from given volumetric chest CT images of patients by extracting its visual features and then using these features in the deep learning module. The proposed convolutional neural network aims to classify the infectious and non-infectious SARS-COV2 subjects. The proposed network utilizes 746 chests scanned CT images of 349 images belonging to COVID-19 positive cases, while 397 belong to negative cases of COVID-19. Our experiment resulted in an accuracy of 98.4%, sensitivity of 98.5%, specificity of 98.3%, precision of 97.1%, and F1-score of 97.8%. The additional parameters of classification error, mean absolute error (MAE), root-mean-square error (RMSE), and Matthew’s correlation coefficient (MCC) are used to evaluate our proposed work. The obtained result shows the outstanding performance for the classification of infectious and non-infectious for COVID-19 cases. 相似文献
179.
Dangi Sambhavna Singh Shrivastava Kavya Bano Mustri Rai Mansi Nema Ankita Khan Farid 《Journal of Materials Science: Materials in Electronics》2022,33(27):21444-21458
Journal of Materials Science: Materials in Electronics - Silver monoliths were prepared using Brij 52 as surfactant with and without dextran and reinforcing agents TiO2NPs by modified sol–gel... 相似文献
180.
Gupta Monish Mittal Vikas Saxena Jyoti Gupta Sushma 《Wireless Personal Communications》2019,109(4):2251-2262
Wireless Personal Communications - These days patch antenna arrays are widely used in various communication systems. In this research design of miniaturized microstrip patch antenna array is... 相似文献