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71.
Danish Muhammad Akhtar Arusa Ashfaq Muhammad Arshad Muhammad Nadeem Asiri Abdullah M. 《Journal of chemical crystallography》2021,51(4):543-552
Journal of Chemical Crystallography - In this paper, we report new sulfonamide derivatives, 4-((2,4-dichlorophenylsulfonamido)methyl)cyclohexanecarboxylic acid (1), ethyl... 相似文献
72.
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
73.
Ahmad Sohail Ashraf Muhammad Ali Kashif 《Journal of Thermal Analysis and Calorimetry》2021,144(3):941-953
Journal of Thermal Analysis and Calorimetry - Among numerous methods which have been employed to reinforce the thermal efficiency in many systems, one is the thermal radiation which is a mode of... 相似文献
74.
Ahmad Shafiq Nadeem Sohail Muhammad Noor Khan Muhammad Naveed 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1187-1199
Journal of Thermal Analysis and Calorimetry - Cattaneo–Christov with variable thermal relaxation time and entropy generation is the main concern of this study. The micropolar fluid with... 相似文献
75.
Dr. Muhammad Sohail Prof. Dr. Fujie Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(1):222-229
Control of chemical reactions is necessary to obtain designer chemical transformation products and for preventing decomposition and isomerization reactions of compounds of interest. For the control of chemical events in aqueous solutions, the use of aqueous buffers is a common practice. However, no molecules that buffer non-aqueous solutions were commonly used. Herein, we demonstrate that 1,3-cyclohexanedione derivatives have buffering functions in non-aqueous solutions. It was also shown that these molecules can be utilized to alter and control chemical reactions. 1,3-Cyclohexanedione derivatives inhibited both acid- and base-catalyzed isomerizations and decompositions in organic solvents. The reaction products obtained in the presence of the buffering molecule 2-methyl-1,3-cyclohexanedione differed from those obtained in the absence of the buffering molecule. The use of buffering molecules that work in organic solvents provides a strategy to control chemical reactions and expands the range of compounds that can be synthesized. 相似文献
76.
Rayleigh and Raman scattering have not been widely used for flow field and combustion imaging because of their very low scattering cross-sections and because of interference from strong background light. With the use of sharp cut-off, atomic and molecular filters this background can be rejected while high throughput is maintained. The sharp cut-off edge of the filters provides for the possibility of using them for high-resolution spectral discrimination. Consequently, Rayleigh and Raman imaging are now becoming feasible and have the promise of providing quantitative images of temperature, velocity, pressure, density, species, and nonequilibrium phenomena. Because Rayleigh and Raman scattering arise from all molecules and are not affected by quenching, quantitative images can be taken of all dominant molecular species as well as thermodynamic and transport properties of complex flows, weakly ionized plasmas, and combusting fields. 相似文献
77.
Sohail H. Zaidi 《Optics and Lasers in Engineering》1997,26(6):473-486
Laser based flow measuring techniques are well known in engineering for their ability to provide useful information in situations where conventional methods either fail or are simply unsuitable due to the harsh flow conditions. High speed turbomachines is one such area where complicated flow phenomena do occur at the inlet and outlet of the impeller. Commercial laser instruments can be used to map the flow in these regions but several other problems have to be solved before any successful results can be obtained. These include geometry of the machine, optical access, seeding, background noise, temperature and the flow conditions at which the laser results are required. This paper illuminates these problems associated with two radial inflow turbines when the flow in the nozzle guide vane region was studied. Several engineering problems were identified and solved prior to achieving successful results. 相似文献
78.
Faruk Güder James Zydiak Sohail Chaudhry 《The Journal of the Operational Research Society》1994,45(10):1197-1205
This paper presents a heuristic algorithm for determining order quantities for multiple items given incremental quantity discounts and a single resourse constraint. The heuristic is based on Lagrangian relaxation. The performance of the heuristic is compared, for small problems, with a procedure that generates optimal solutions. Results from computational experiments are given that demonstrate the quality and computational efficiency of the heuristic algorithm. 相似文献
79.
Guo-Zhang Huang Ze-Yu Ruan Jie-Yu Zheng Jie-Yi Wu Yan-Cong Chen Quan-Wen Li Muhammad Nadeem Akhtar Jun-Liang Liu Ming-Liang Tong 《中国科学:化学(英文版)》2018,61(11):1399-1404
Single-molecule magnets (SMMs) are regarded as promising candidates for ultrahigh-density storage, quantum information processing and molecular spintronics. It is a crucial challenge for chemists to modulate magnetic dynamics of SMMs. Here, we successfully synthesized two 3d-4f polynuclear compounds [Co2Dy(TTTTCl)2(MeOH)]NO3·3MeOH (1) and [Co2Dy(TTTTCl)2 (MeOH)][Co(HTTTTCl)](NO3)2·2.5MeOH·2H2O (2), where H3TTTTCl=2,2′,2′′-(((nitrilotris(ethane-2,1-diyl)) tris(azanediyl)) tris(methylene))tris-(4-chlorophenol). On applying the approach by co-crystallization of bulky diamagnetic moiety, the effective energy barrier enhances from 401 K (1) to 536 K (2), which are both among the highest d-f heterometallic SMMs. 相似文献
80.
Yueyue?Song Guanhong?Xu Fangdi?Wei Yao?Cen Muhammad?Sohail Menglan?Shi Xiaoman?Xu Yunsu?Ma Yujie?Ma Qin?HuEmail author 《Mikrochimica acta》2018,185(2):139
The authors describe an aptamer-based fluorescent assay for adenosine (Ade). It is based on the interaction between silver nanoparticles (AgNPs) and CdTe quantum dots (QDs). The beacon comprises a pair of aptamers, one conjugated to Fe3O4 magnetic nanoparticles, the other to AgNPs. In the presence of Ade, structural folding and sandwich association of the two attachments takes place. After magnetic separation, the associated sandwich structures are exposed to the QDs. The AgNPs in sandwich structures act as the signaling label of Ade by quenching the fluorescence of QDs (at excitation/emission wavelengths of 370/565 nm) via inner filter effect, electron transfer and trapping processes. As a result, the fluorescence of QDs drops with increasing Ade concentration. The assay has a linear response in the 0.1 nM to 30 nM Ade concentration range and a 60 pM limit of detection. The assay only takes 40 min which is the shortest among the aptamer-based methods ever reported. The method was successfully applied to the detection of Ade in spiked biological samples and satisfactory recoveries were obtained. 相似文献