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排序方式: 共有641条查询结果,搜索用时 15 毫秒
1.
Dinesh R. Hussain S. Imran Roseline A. Ameelia Kalaiselvam S. 《Journal of Thermal Analysis and Calorimetry》2021,145(6):2935-2949
Journal of Thermal Analysis and Calorimetry - In this paper, the variation of thermophysical properties such as the thermal conductivity, thermal energy storage capacity, viscosity, and phase... 相似文献
2.
J.H. Sung J.Y. Park T. Imran Y.S. Lee C.H. Nam 《Applied physics. B, Lasers and optics》2006,82(1):5-8
Optical pulses with 1.1-mJ energy and 5.5-fs duration have been generated at 1-kHz repetition rate from a chirped pulse amplification
Ti:Sapphire laser incorporating a differentially pumped hollow-fiber chirped-mirror compressor. The effects of self-focusing
and multi-photon ionization during the beam propagation were minimized by differentially pumping the hollow fiber filled with
neon. The spectral broadening at the hollow-fiber compressor was optimized by adjusting gas pressure, laser intensity, and
laser chirp, covering from 540 nm to 950 nm.
PACS 42.65.Jx; 42.65.Re 相似文献
3.
Sajid Husain Ponnapalli Nageswara Sarma Sankarayya Swamy 《Journal of separation science》1995,18(7):422-424
A capillary GC method employing an internal standard has been developed and successfully used for quantitative determination both of the raw materials used for the manufacture of m-phenoxybenzaldehyde and for the components of the reaction mixtures obtained at various stages of the development of the process. A complete analysis can be performed in a single temperature programmed run. 相似文献
4.
In view of the attributed medicinal properties of beta-carboline alkaloids, some new O-acyl derivatives of beta-carboline alkaloid--harmol, were prepared and tested for possible antimycobacterial activity against Mycobacterium tuberculosis H37Rv. 相似文献
5.
7-Ethyl-10-hydroxycamptothecin (SN-38) is an active metabolite of Irinotecan (CPT-11), an anticancer pro-drug. To support clinical pharmacokinetic studies for liposome based formulation of SN-38 (LE-SN38) in cancer patients, a rapid, simple and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the quantification of total SN-38 in human plasma. Sample preparation was carried out by one-step protein precipitation using cold acetonitrile with 0.5% acetic acid (v/v). Camptothecin was used as an internal standard (IS). Chromatographic separation of SN-38 and IS was achieved using a Synergi Hydro-RP column (C(18), 50 x 2 mm, 4 micro m), with a gradient elution of acetonitrile and 0.1% acetic acid. After ionization in electrospray source (positive ions), the acquisition was performed in the multiple reactions monitoring mode. Quantitation was accomplished using the precursor-->product ion combinations of m/z 393.1-->349.2 for SN-38 and 349.1-->305.1 for IS. The quantification limit of 0.05 ng/mL was achieved by using much lower volume (0.2 mL) of plasma and in the presence of LE-SN38. The method was validated over the concentration range of 0.05-400 ng/mL. Accuracy was within +/-12% of nominal at all concentration levels. Inter-day and intra-day precisions expressed as percentage coefficient of variation (%CVs) for quality control (QC) samples were less than 14 and 5%, respectively. 相似文献
6.
This paper investigates the rotating flow and heat transfer of a viscous fluid induced by a stretching surface. The nonlinear problem subject to a given skin friction at the boundary is solved. Analytic solution is obtained using homotopy analysis method. The velocity, temperature, and stretching velocity is calculated for different values of the rotation parameter (λ). The obtained results are compared with the well known results of rotating flow induced by a stretching surface by using four sets of boundary conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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8.
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
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10.
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