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排序方式: 共有116条查询结果,搜索用时 31 毫秒
81.
82.
Maheshwaran C. Kanchan D.K. Gohel Khushbu Mishra Kuldeep Kumar Deepak 《Journal of Solid State Electrochemistry》2020,24(3):655-665
Journal of Solid State Electrochemistry - In the present study, a magnesium ion conducting polymer electrolyte membrane system based on polyethylene oxide (PEO) containing magnesium triflate... 相似文献
83.
An efficient Rh(II) acetate catalyzed highly diastereoselective cyclopropanation of styrenes with enaldiazo esters has been developed (up to >95:5 dr and 62–82% yield). The reaction is proposed to involve diacceptor electrophilic rhodium enalcarbenoids and constitutes the first direct synthesis of enal-cyclopropanes with an all carbon γ-quaternary stereocenter. 相似文献
84.
Nidhi Kalgotra Bhawana Gupta Kuldeep Kumar Sushil K. Pandey 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):364-375
Abstract Reactions of O-tolyldithiocarbonate ligands, (o-, m-, and p-CH3C6H4O)CS2Na, with anhydrous FeCl2 (1:2 molar ratio) and with FeCl3 (1:1 and 1:3 molar ratio) yielded the complexes [{(CreO)CS2}2Fe] and [{(CreO)CS2}nFeCl3–n] (Cre = o-, m-, and p-CH3C6H4; n = 1 and 3), respectively. These complexes were reacted with nitrogen and phosphorus donor ligands in dichloromethane, which afforded the adducts corresponded to [{(CreO)CS2}2Fe.xL] and [(CreO)CS2FeCl2.xL] {x = 1, L = N2C12H8; x = 2, L = NC5H5, P(C6H5)3}. Elemental analyses and IR, UV-visible, and mass spectroscopic and magnetic studies indicated bidentate mode of bonding by dithiocarbonate ligands leading to sixcoordination around the iron atom as a consequence of Fe…Fe interaction in the complexes [{(CreO)CS2}2Fe] and [(CreO)CS2FeCl2]. The complexes exhibited antifungal activity. The fungicidal activity of the complexes has been tested by poisoned food technique using fungi Fusarium sp. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Antifungal Activity. 相似文献
85.
This article describes the structure of the graph minimizing the algebraic connectivity among all connected graphs made with some given blocks with fixed number of pendant blocks, the blocks that have exactly one point of articulation. As an application, we conclude that over all graphs made with given blocks, the algebraic connectivity is minimum for a graph whose block structure is a path. 相似文献
86.
A layered nanohybrid comprising of multi walled carbon nanotubes(MWCNT)‐gold nanoparticles (AuNPs) has been designed as a matrix for the development of Au dendritic nanostructures (AuDN) with enhanced catalytic activity. The developed sensor matrix was thoroughly characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X‐ray spectroscopy (EDX). The developed sensor probe MWCNT‐AuNPs/AuDN over glassy carbon electrode (GCE) was used for the label free detection of acetaminophen (AP), a commonly used drug associated with hepatotoxicity when overdosed, as a model molecule. The final sensor probe was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV). The sensor shows excellent analytical performances with a linear dynamic range (LDR) of 100 to 7500 nM, and a low limit of detection (LOD) of 2.12 (±0.03) nM, which is better than recently reported AP sensors. The practical application / clinical possibilities of the final sensor were evaluated by real sample analysis in human urine by spike and recovery method, where the AP recoveries were found in between 92 % to 96 %. The sensor probe shows negligible response towards co‐existing interfering molecules like glucose, urea, uric acid and various amino acids, which are commonly found in real samples (p<0.001, n=3). The shelf life of the sensor probe was evaluated and found to be stable for 8 weeks. The fabricated sensor probe using MWCNT‐AuNPs/AuDN is easy to fabricate, simple, robust, and able to detect AP in urine with high recoveries shows its possibilities to be used in clinical settings. 相似文献
87.
88.
Kuldeep Wadhwa Chengxi Yang Kris C. Deming Sanjay R. Chemburkar Rajarathnam E. Reddy 《合成通讯》2013,43(24):4434-4444
Abstract A variety of substituted arylglyoxylic acids (2a?g) were synthesized via oxidation of the corresponding aryl-methylketones (1a–e) using selenium dioxide or Friedel–Crafts acylation of phenol (3) with ethyl chlorooxoacetate and further transformations. It was found that the arylglyoxylic acids (2) undergo facile unimolecular dissociation with loss of carbon monoxide to give the corresponding arylcarboxylic acids (7) under collisionally induced mass spectrometric conditions. 相似文献
89.
The present study demonstrates the interfacial interplay between transition metal salt (TMS) additive and range of non-aqueous lyotropic mesophases. Structural aspect reveals the substantial influence of the additive addition on the self-assembly and packing of micelles as intense growth of hexagonal planes was seen in the vicinity of the pre-existed lamellar mesophase (as the surfactant concentration loomed to the higher value in the parent binary mixture). Such structural modulations certainly resulted from reduction in optimal surface area of head group and packing parameter under the influence of interfacial interactions amid charged counter ions and metal salt additive. The origin and thermal stability of hexagonal ordering have been addressed and discussed. 相似文献
90.
This study highlights the effects of amphiphile chain length and counter ions on the self-assembly and dielectric behaviour of non-aqueous lyotropic liquid crystals. Two-dimensional hexagonal mesophase is seen for short-chain length sodium dodecyl sulphate, while lamellar and multiwall lamellar mesophases are noticed for long-chain length cetyltrimethylammonium bromide and polyoxyethylene (20) sorbitan monolaurate amphiphiles in the non-aqueous domains of ethylene glycol. A strong influence of amphiphile counter ions is seen on static dielectric constant, loss factor, relaxation frequency and relaxation time of these lyotropic mixtures. Refractive indices of these lyotropic phases are also highlighted. 相似文献