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排序方式: 共有331条查询结果,搜索用时 31 毫秒
1.
Catalysis Letters - A new zirconium based carbonaceous solid acid catalyst Zr@CC-PA with both Lewis and Bronsted acidic sites was prepared by simultaneous carbonization and phosphonation of glucose... 相似文献
2.
F.T. Munna Vidhya Selvanathan K. Sobayel Ghulam Muhammad Nilofar Asim Nowshad Amin Kamaruzzaman Sopian Md. Akhtaruzzaman 《Ceramics International》2021,47(8):11003-11009
In this study, dilute chemical bath deposition technique has been used to deposit CdZnS thin films on soda-lime glass substrates. The structural, morphological, optoelectronic properties of as-grown films have been investigated as a function of different Zn2+ precursor concentrations. The X-ray diffractogram of CdS thin-film reveals a peak corresponding to (002) plane with wurtzite structure, and the peak shift has been observed with the increase of the Zn2+ concentration upon formation of CdZnS thin film. From morphological studies, it has been revealed that the diluted chemical bath deposition technique provides homogeneous distribution of film on the substrate even at a lower concentration of Zn2+. Optical characterization has shown that the transparency of the film is influenced by Zn2+ concentration and when the Zn2+ concentration is varied from 0 M to 0.0256 M, bandgap values of resulting films range from 2.42 eV to 3.90 eV while. Furthermore, electrical properties have shown that with increasing zinc concentration the resistivity of the film increases. Finally, numerical simulation validates and suggests that CdZnS buffer layer with composition of 0.0032 M Zn2+ concentration would be a promising candidate in CIGS solar cell. 相似文献
3.
4.
Dr. Sivaraman Balasubramaniam Dr. Sneh Badle Dr. Swati Badgujar Dr. Vinod P. Veetil Dr. Vidhya Rangaswamy 《Chembiochem : a European journal of chemical biology》2021,22(4):705-711
A method for producing buta-1,3-diene (1,3-BD) by an amalgamation of chemical and biological approaches with syngas as the carbon source is proposed. Syngas is converted to the central intermediate, acetyl-CoA, by microorganisms through a tetrahydrofolate metabolism pathway. Acetyl-CoA is subsequently converted to malonyl-CoA using a carbonyl donor in the presence of a carboxylase enzyme. A decarboxylative Claisen condensation of malonyl-CoA and acetaldehyde ensues in the presence of acyltransferases to form 3-hydroxybutyryl-CoA, which is subsequently reduced by aldehyde reductase to give butane-1,3-diol (1,3-BDO). An ensuing dehydration step converts 1,3-BDO to 1,3-BD in the presence of a chemical dehydrating reagent. 相似文献
5.
Wireless Personal Communications - With emerge of increasing research in domain of future wireless communications, massive multiple input multiple output (MIMO) attracted most of researchers... 相似文献
6.
Khan Mohd Moiz Singh Manvendra Jadhav G. N. Mahajani S. M. Mandre Shashank 《SILICON》2020,12(3):677-691
Silicon - The aim of this study is to discuss the importance of characterization of green, waste green and reclaimed sand. The transformations and changes which take place in the green sand, are... 相似文献
7.
Iranian Polymer Journal - Composites derived from petroleum sources like epoxy, unsaturated polyester and phenolics have limitations due to non-biodegradability toxicity which have harmful effects... 相似文献
8.
V. Maheskumar P. Gnanaprakasam T. Selvaraju B. Vidhya 《International Journal of Hydrogen Energy》2018,43(8):3967-3975
The development of non-precious metal based electrocatalysts is essential for Hydrogen Evolution Reaction (HER) from the splitting of water. Recently copper tin sulphide (CTS) has gained attention due to its favourable properties in photovoltaic devices and photocatalysis. In this work, CTS has been explored as an electrocatalyst in HER. Cu2SnS3 (CTS (A)) and Cu4SnS4 (CTS (B)) are prepared by a simple solvothermal method. From the XRD analysis, tetragonal and orthorhombic phase is confirmed for CTS (A) and CTS (B), respectively. Morphology and composition of the prepared samples has been confirmed by SEM and EDAX analysis. Optical study reveals that the band gap energy is around 1.55 and 1.20 eV for CTS (A) and CTS (B), respectively. From photoluminescence studies, CTS (B) has been observed to have a greater recombination of charge carriers than CTS (A). The prepared materials were tested and compared for its performance as electrocatalysts for HER, where the current density of CTS (A) is higher than that of CTS (B). Furthermore, the calculated Tafel slope was 98 mV/dec and 110 mV/dec for CTS (A) and CTS (B), respectively. On the other hand, CTS (A) and CTS (B) have showed good stability even after 500 cycles in acidic medium. 相似文献
9.
Wireless Personal Communications - Nonnegative Matrix Factorization (NMF) has been becoming an important method for feature dimension reduction in recent years since it can represent data with... 相似文献
10.
Buoyancy forces result from the cooling or heating of a continuous stretching sheet, which causes a change in the resulting flow and thermal fields, and hence the heat transfer behavior in the manufacturing process. The study of the thermal buoyancy induced in boundary layer flow is important due to its recent advances in the areas of nuclear energy, electronics, and space technology. In this perspective, the aim of the present study is to investigate the effect of the buoyancy parameter on the magnetohydrodynamics boundary layer flow over an exponentially stretched sheet in the presence of nonlinear thermal radiation and porous media. Using similarity transformation, the flow model of partial differential equations is transformed into a set of coupled nonlinear ordinary differential equations. The efficient fourth‐order Runge‐Kutta scheme with the shooting method is used to solve the reduced equations. The impact of various associated parameters on velocity and temperature profiles were analyzed and computed through graphs. The major outcome of the present study shows the enhancement in the velocity distribution with the increase in the buoyancy parameter. Also, the increase in thermal buoyancy and thermal radiation leads to an increase in fluid temperature. Moreover, it is worth to note that the fluid velocity declines with the augmentation of the magnetic parameter. 相似文献