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11.
Md Sabir Alam Md Noushad Javed Faheem Hyder Pottoo Aafrin Waziri Faisal A. Almalki Md Saquib Hasnain Arun Garg Md Khalid Saifullah 《应用有机金属化学》2019,33(9)
Microwave irradiation (MI) process characteristically enables extremely rapid “in‐core” heating of dipoles and ions, in comparison to conventional thermal (conductance) process of heat transfer. During the process of nanoparticles synthesis, MI both modulates functionality behaviors as well as dynamic of reaction in favorable direction. So, MI providing a facile, favorable and alternative approach during nanoparticles synthesis nanoparticles with enhanced catalytic performances. Although, conventionally used reducing and capping reagents of synthetic origin, are usually environmentally hazardous and toxic for living organism. But, in absence of suitable capping agent; stability, shelf life and catalytic activity of metallic nanoparticles adversely affected. However, polymeric templates which emerged as suitable choice of agent for both reducing and capping purposes; bearing additional advantages in terms of catalyst free one step green synthesis process with high degree of biosafety and efficiency. Another aspect of current works was to understand role of process variables in growth mechanism and catalytic performances of microwave processed metallic nanoparticles, as well as comparison of these parameters with conventional heating method. However, due to poor prediction ability with previously published architect OFAT (One factor at a time) design with these nanoparticles as well as random selection of process variables with their different levels, such comparison couldn't be possible. Hence, using gum Ghatti (Anogeissus latifolia) as a model bio‐template and under simulated reaction conditions; architect of QbD design systems were integrated in microwave processed nanoparticles to establish mechanistic role these variables. Furthermore, in comparison to conventional heating; we reported well validated mathematical modeling of process variables on characteristic of nanoparticles as well as synthesized gold nanoparticles of desired and identical dimensions, in both thermal and microwave‐based processes. Interestingly, despite of identical dimension, MI processed gold nanoparticles bearing higher efficiency (kinetic rate) against remediation of hazardous nitro dye (4‐nitrophenol), into safer amino (4‐aminophenol) analogues. 相似文献
12.
13.
Journal of Solid State Electrochemistry - Graphene nanosheets (G) and pure, as well as doped Mg-, Mn-, V-Li4Ti5O12, spinel structure have been synthesized. As-prepared materials were characterized... 相似文献
14.
M. Rafiq H. Siddiqui S.F. Adil K. Nour M.E. Assal A. Al-Warthan 《Arabian Journal of Chemistry》2013,6(4):435-438
Silver chloride was found to be stable even after calcination at 650 °C for 10 h. SEM studies revealed the morphology of silver chloride as hexagonal particles. TEM studies show the size of silver chloride particles to have an average size of 6–7 nm. Thermal studies suggest that silver chloride nanoparticles behave like ionic liquid or molten salt in the range of 455–650 °C. 相似文献
15.
M. Rafiq S. Ali S. Shahzadi M. Shahid S. K. Sharma K. Qanungo 《Journal of the Iranian Chemical Society》2014,11(1):169-178
Organotin complexes have been synthesized by refluxing 2-mercapto-5-methyl benzimidazole with R2SnCl2/R3SnCl (R = Me, n-Bu, Ph) in 1:1 molar ratio in the first step. In the second step, synthesized organotin(IV) complexes were treated with CS2 and R2SnCl2/R3SnCl/PdCl2 to yield homo- and heterobimetallic complexes. The composition of the synthesized complexes, the bonding behavior of the donor groups, and structural assignments were studied by elemental analysis and different spectral techniques, including IR and multinuclear NMR (1H, 13C). The IR data shows bidentate nature of the ligand which is also confirmed by semiempirical study, while NMR data confirms the four-coordinated geometry in solution. The free ligand and its respective homo- and heterobimetallic complexes were screened in vitro against a number of microorganisms to assess their biocidal properties. The biological activity data show that complexes exhibits significant antibacterial and antifungal activities as compared to ligand with few exceptions. 相似文献
16.
Queiroz Ana Luiza P. Kerins Brian M. Yadav Jayprakash Farag Fatma Faisal Waleed Crowley Mary Ellen Lawrence Simon E. Moynihan Humphrey A. Healy Anne-Marie Vucen Sonja Crean Abina M. 《Cellulose (London, England)》2021,28(14):8971-8985
Cellulose - Microcrystalline cellulose (MCC) is a semi-crystalline material with inherent variable crystallinity due to raw material source and variable manufacturing conditions. MCC crystallinity... 相似文献
17.
Electromagnetic interference (EMI) shielding has become a phenomenon of great concern and there is growing demand towards the synthesis of materials with better EMI shielding effectiveness (EMI SE). This work highlights the preparation of Polyaniline-Yttrium Oxide (PANI-Y2O3) composites for EMI shielding applications in the frequency range from 12.4 to 18 GHz (Ku-band). The structure and morphology of the composites were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). EMI SE, microwave absorption and reflection, dielectric properties of the composites are discussed in detail. All the computations were based on microwave scattering parameters measured by transmission line waveguide technique. The observed results show absorption dominant EMI shielding in these composites with EMI SE of ?19 to ?20 dB, which mainly depends on the dielectric loss of the composites. Through the results of our observations, we propose these composites to be potential materials for microwave absorption and EMI shielding applications. 相似文献
18.
Gamal A. Soliman Rehab F. Abdel-Rahman Hanan A. Ogaly Hassan N. Althurwi Reham M. Abd-Elsalam Faisal F. Albaqami Maged S. Abdel-Kader 《Molecules (Basel, Switzerland)》2020,25(22)
More than 90% of diabetic patients suffer from sexual dysfunction, including diminished sperm count, sperm motility, and sperm viability, and low testosterone levels. The effects of Momordica charantia (MC) were studied by estimating the blood levels of insulin, glucose, glycosylated hemoglobin (HbA1c), testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in diabetic rats treated with 250 and 500 mg/kg b.w. of the total extract. Testicular antioxidants, epididymal sperm characteristics, testicular histopathology, and lesion scoring were also investigated. Testicular mRNA expression of apoptosis-related markers such as antiapoptotic B-cell lymphoma-2 (Bcl-2) and proapoptotic Bcl-2-associated X protein (Bax) were evaluated by real-time PCR. Furthermore, caspase-3 protein expression was evaluated by immunohistochemistry. MC administration resulted in a significant reduction in blood glucose and HbA1c and marked elevation of serum levels of insulin, TST, and gonadotropins in diabetic rats. It induced a significant recovery of testicular antioxidant enzymes, improved histopathological changes of the testes, and decreased spermatogenic and Sertoli cell apoptosis. MC effectively inhibited testicular apoptosis, as evidenced by upregulation of Bcl-2 and downregulation of Bax and caspase-3. Moreover, reduction in apoptotic potential in MC-treated groups was confirmed by reduction in the Bax/Bcl-2 mRNA expression ratio. 相似文献
19.
Faisal Muhammad Saeed Aamer Shahzad Danish Dar Parsa Larik Fayaz Ali 《Molecular diversity》2020,24(2):571-592
Molecular Diversity - Aldehydes and ketones are parts of millions of compounds and are important classes of chemicals which serve as important precursors for the synthesis of library of compounds.... 相似文献
20.
The possibility of simultaneous induction and detection, with an intense single mode ir laser, of the Autler Townes splittings of certain rovibrational lines in diatomics is discussed. A model based on the accurately known molecular parameters and dipole matrix elements of CO is used to exhibit the power splitting effect for the case of two quantum excitation. The power splitting effect, which exhibits a threshold as a function of laser intensity is clearly discernable in both the two and one quantum absorption profiles as well as in the total absorption spectrum. Using a simple qualitative rule we predict that such rovibrational line splittings should also be observable in an analogous set of transitions in other diatomics. 相似文献