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81.
Aimen Zafar Shaan Bibi Jaffri Manzar Sohail 《Phosphorus, sulfur, and silicon and the related elements》2021,196(1):36-46
Abstract This work reports the first investigation on the physical vapor deposition of thin films of tin sulfide doped lead sulfide (SnS:PbS). In-situ synthesis route using diethyldithiocarbamate (DTC) ligand was adopted for SnS-DTC, PbS-DTC and SnS:PbS-DTC complex formation. PbS-DTC and SnS:PbS-DTC expressed an average crystallite size of 30.98 and 29.74?nm, respectively shown by X-ray diffraction (XRD) analysis. A face centered cubic geometry was revealed from XRD. Ultraviolet visible spectrophotometry expressed a direct and indirect band gap of 3.4 and 3.2?eV, respectively for SnS:PbS-DTC. A smooth morphology with presence of larger agglomerated particles was disclosed by scanning electron microscopy for SnS:PbS-DTC thin films with 615?nm thickness. SnS:PbS-DTC thin films expressed remarkable electrochemical behavior explored via cyclic voltammetry, linear sweep voltammetry and chronoamperometry showing an improvement in the photo-current response upon potential bias increment. The results of the current research indicated the potential of SnS:PbS-DTC thin films for utilization in different types of photovoltaic devices. 相似文献
82.
I. E. Qureshi M. I. Shahzad S. Manzoor M. S. Zafar H. A. Khan 《Radiation measurements》1997,28(1-6):283-286
One of the main advantages of using dielectric track detectors in the study of heavy ion interactions is the possibility of observing each multi-prong event individually with complete kinematical details. It is thus possible to analyze even those reaction channels that have very low branching ratios. In the study of reactions induced by 16.7 MeV/u uranium ions incident on natural gold targets, we have observed 18 four-pronged events in a total detector area of 24 cm2. Using a polynomial range-energy relationship, empirically fitted to the observed data of binary and ternary events, it was possible to perform kinematical analysis of 10 out of 18 events. The masses and relative velocities of the reaction products, determined in this analysis were compared with theoretical prediction based on double sequential fission process. An agreement within one standard deviation with respect to theoretical values has been found for eight analysed events. 相似文献
83.
P. Čížek M. Finger J. John T. I. Kracíková V. N. Pavlov P. Pokorný P. Šimečková V. M. Tsupko-Sitnikov J. Zafar Z. Janout B. Sedlák 《Hyperfine Interactions》1988,43(1-4):163-166
The Spin-2 facility built at YASNAPP-2 experimental complex of the Joint Institute of Nuclear Research is described. The basic
parameters of SPIN-2 and YASNAPP-2 are discussed. 相似文献
84.
Zafar Ahmad Siddiqi Shahla Nusrat Qidwai Maimoona Jaria Mohd Shakir 《Transition Metal Chemistry》1988,13(4):244-246
Summary Reactions ofN-trimethylsilylimidazole andN-trimethyl-silyl-2-methylimidazole with CoCl2 yield chloro(imidazolato)cobalt(II), (1), or chloro(2-methylimidazolato)-cobalt(II), (2). However, the corresponding reactions of [Co(Ph3P)2Cl2] cause total removal of Ph3P along with the substitution of both the chlorine atoms yielding bis(imidazolato)cobalt(II), (3), or bis(2-methylimidazolato)cobalt(II), (4), in the form of light blue microcrystalline solids. The complexes have been characterized by elemental analysis, molecular weight, and magnetic susceptibility measurements, and i.r., reflectance and electronic spectra. The results are consistent with formulations as rare examples of two-coordinate cobalt(II) derivatives.Author to whom all correspondence should be directed 相似文献
85.
Through several waves of technological research and un-matched innovation strategies, bio-catalysis has been widely used at the industrial level. Because of the value of enzymes, methods for producing value-added compounds and industrially-relevant fine chemicals through biological methods have been developed. A broad spectrum of numerous biochemical pathways is catalyzed by enzymes, including enzymes that have not been identified. However, low catalytic efficacy, low stability, inhibition by non-cognate substrates, and intolerance to the harsh reaction conditions required for some chemical processes are considered as major limitations in applied bio-catalysis. Thus, the development of green catalysts with multi-catalytic features along with higher efficacy and induced stability are important for bio-catalysis. Implementation of computational science with metabolic engineering, synthetic biology, and machine learning routes offers novel alternatives for engineering novel catalysts. Here, we describe the role of synthetic biology and metabolic engineering in catalysis. Machine learning algorithms for catalysis and the choice of an algorithm for predicting protein-ligand interactions are discussed. The importance of molecular docking in predicting binding and catalytic functions is reviewed. Finally, we describe future challenges and perspectives. 相似文献
86.
Zafar Ali Shah Saba Farooq Syed Abid Ali Abdul Hameed M. Iqbal Choudhary 《合成通讯》2018,48(10):1172-1182
The peptide temporin-LK1 (1) was obtained from the skin secretion of frog Limnonectes kuhlii (Ranidae). It is a unique antimicrobial peptide with 17 residues, including four L-phenylalanines and single glycine. Mass spectrometry and Edmand degradation were used for the determination of sequence of amino acids in temporin-LK 1 (1), and confirmed by cDNA cloning. We report here the synthesis and structural studies of temporin-LK1 (1) and its analogs 2–4. Peptides 2–4 were prepared by substitution of achiral glycine residue of temporin-LK1 (1) with D-alanine, L-phenylglycine, and L-naphthylalanine, respectively. Peptides 1–4 were evaluated against multidrug-resistant (MDR) strains of Staphylococcus aureus and Pseudomonas aeruginosa. Analog 2 was found active against all MDR strains of S. aureus and P. aeruginosa at a much lower dose than the clinically used antibiotics. 相似文献
87.
88.
Summary Reaction of 4-cyano-5-aminopyrazole, Hcpz, with ammoniacal solutions of metal(I) chlorides yields colorless and insoluble polymeric complexes, [Mcpz]n [where M=Cu(1) or Ag(2)]. However, pyrazolidebridged dimeric species [M(PPh3)2cpz]2
(3) or(4), soluble in most non-polar solvents, were obtained from the precursor [M(PPh3)3X] (X=Cl or NO3) under similar reaction conditions. The compounds have been characterized using physico-chemical methods and are diamagnetic. 相似文献
89.
Muhammad Sher Zafar Ahmed Muhammad A. Rashid Anke Spannenberg Peter Langer 《Tetrahedron》2007,63(23):4929-4936
Functionalized and sterically encumbered diaryl ethers were prepared by [3+3] cyclization of 1,3-bis(silyl enol ethers) with 2-aryloxy-3-(silyloxy)alk-2-en-1-ones. 相似文献
90.
Mohammad Shakir Ajax K. Mohamed Saji P. Varkey Zafar A. Siddiqi 《Transition Metal Chemistry》1996,21(2):162-165
Summary The synthesis of a new series of 14- and 16-membered hexaazamacrocyclic complexes has been achieved by the template condensation of ethylenediamine or 1,3-propylenediamine with formaldehyde and acetamide in a 121 molar ratio in the presence of metal chlorides. Octahedral structural formulae for selective metal complexes are proposed on the basis of physico-chemical and spectroscopic data. The redox behaviour in DMSO solution of the CuII complexes has been studied by cyclic voltammetry. 相似文献