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51.
A. Gopalakrishna G. N. Kim H. Naik K. Kim B. K. Nayak Muhammad Zaman 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):561-569
The production cross-section of the medical isotope, 99Mo from the enriched 100Mo(n,2n) reaction with the average neutron energies of 21.9 and 26.5 MeV has been determined for the first time by using an off-line γ-ray spectrometric technique. The average neutron energies were generated by using the 9Be(p,n) reaction with the proton energies of 35 and 45 MeV from the MC50 cyclotron of the Korea Institute of Radiological and Medical Sciences (KIRAMS) at Seoul, South Korea. The 100Mo(n,2n) reaction cross-section as a function of neutron energy was also calculated theoretically by using the computer code TALYS-1.8 and EMPIRE-3.2 Malta. The experimental results are in close agreement with the theoretical values from TALYS-1.8. However, the present data at the neutron energy of 21.9 MeV is slightly lower and at 26.5 MeV is higher than the values from EMPIRE-3.2 Malta. 相似文献
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Muhammad Imran ul‐haq Rajesh A. Shenoi Donald E. Brooks Jayachandran N. Kizhakkedathu 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2614-2621
Hyperbranched polyglycerols (HPGs) are globular structures with a large number of functionalizable hydroxyl groups and have excellent in vitro and in vivo biocompatibility profiles comparable to polyethylene glycol. This work introduces a facile method for the synthesis of medium molecular weights (Mws) (50–300 kDa) HPGs, which has been difficult to synthesize with low polydispersity, with the assistance of solvents by ring opening polymerization. The influence of different solvents (1,4‐dioxane, tetrahydropyran (THP), ethylene glycol diethyl ether (EGDE) and decane), solvent to glycidol ratio, concentration of glycidol and the time of polymerization on Mw and polydispersity of HPGs has been studied. The Mw and polydispersity of HPGs are significantly affected by the nature of the polymerization phase (homogeneous or heterogeneous) and chemical structure of the solvent. The differences in the solvation of the potassium cations and change in the nucleophilicity of the alkoxide anion in various solvents may be responsible for the changes in Mw and PDI of the HPG. The Mw of the HPG decreases in the order 1,4‐dioxane > THP > EGDE >decane. The microstructure, solution and thermal properties of the HPG do not depend on the nature of solvent. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2614–2621 相似文献
53.
Muhammad Sajid 《Ionics》2018,24(1):19-32
Bentonites are promising materials for electrochemical sensing because of their unique physicochemical properties. They have relatively high surface area, good adsorption and ion-exchange ability, highly tunable surface and interlayer composition, non-toxic nature, and excellent biocompatibility. Moreover, they are outstanding substrates for stable immobilization of different functional moieties. The primary focus of this review article is to highlight the applications of bentonite-modified electrodes for the analysis of organic and inorganic analytes in different matrices. A brief summary on the necessity of analysis of different compounds is provided. For the first time, features and applications of bentonite-modified electrodes are critically appraised. The key features of bentonite-modified electrodes that enhance their electrocatalytic activity toward detection of certain target analytes are highlighted. At the end, an account of current status of bentonite-modified electrodes along with future research directions is provided. 相似文献
54.
Composites of polyaniline with yttrium oxide (Y2O3) nanoparticles have been prepared by chemical polymerizations method by increasing the weight percentage of yttrium oxide. X-Ray diffraction (XRD) and Fourier Transform Infrared Spectra (FTIR) were used to characterize the composites. XRD and FTIR pattern indicate that Polyaniline (PANI) is intercalated into the layers of Y2O3 nanoparticles successfully by in situ polymerization and therefore the degree of crystallinity increases due to crystalline of yttrium oxide nanoparticles. The scanning electron micrographs (SEM) also confirm the formation of dual phase of platelet as well as of flaky structure in PANI-Y2O3. Temperature dependant DC conductivity showed three dimensional variable ranges hopping (3D VRH) model. Activation energy, density of states and hopping length are calculated and found to be influenced by intercalating PANI into the layers of Y2O3 clay. 相似文献
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Shahan Zeb Khan Muhammad Kashif Amir Imdad Ullah Asma Aamir John M. Pezzuto Tamara Kondratyuk Francine Bélanger‐Gariepy Akbar Ali Sajid Khan Zia‐ur‐Rehman 《应用有机金属化学》2016,30(6):392-398
Two new heteroleptic palladium(II) complexes have been synthesized by reacting equimolar quantities of palladium(II) chloride, sodium 4‐(2‐methoxyphenyl)piperazine‐1‐carbodithioate and diphenyl‐p‐tolylphosphine ( 1 ) or tri‐p‐tolylphosphine ( 2 ). Complexes 1 and 2 have been characterized using elemental analysis, Fourier transform infrared spectroscopy, multinuclear NMR (1H, 13C and 31P) spectroscopy and single‐crystal X‐ray analysis. The latter technique confirms a pseudo square‐planar geometry in which two adjacent positions are occupied by bidentate dithiocarbamate while chloro and substituted triphenylphosphine are present at the remaining two positions. The anticancer activity of both complexes against five different cancer cell lines (LU – human lung carcinoma, established at UIC, Department of Surgical Oncology; MCF7 – human breast adenocarcinoma, ATCC number HTB‐22?; MDA‐MB‐231 – human breast adenocarcinoma, ATCC number HTB‐26?; Hepa‐1c1c7 – mouse liver hepatoma, ATCC number CRL‐2026?; PC‐3 – human prostate adenocarcinoma, ATCC number CRL‐1435?) was determined by MTT assay, revealing 2 has higher activity than 1 . A drug–calf thymus DNA binding study with UV–visible spectroscopy reveals a higher DNA binding affinity of 2 (3.511 × 104 M?1) than 1 (4.213 × 103 M?1). Density functional theory studies confirm the relatively more stable nature of 2 than 1 . Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
58.
Dr. Ji-Rong Huang Dr. Muhammad Sohail Dr. Tohru Taniguchi Prof. Dr. Kenji Monde Prof. Dr. Fujie Tanaka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5947-5951
Spiro[4,5]decanes and polycyclic compounds bearing spiro[4,5]decane systems are important biofunctional molecules. Described are diastereoselective formal (4+1) cycloaddition reactions to afford oxindole-functionalized spiro[4,5]decanes and organocatalytic enantioselective Michael–Henry cascade reactions of the (4+1) cycloaddition products to generate spirooxindole polycyclic derivatives bearing the spiro[4,5]decane system. Spiro[4,5]decanes bearing oxindoles containing three stereogenic centers and spirooxindole polycycles having seven stereogenic centers, including two all-carbon chiral quaternary centers and one tetrasubstituted chiral carbon center, were obtained with high diastereo- and enantioselectivities. 相似文献
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