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排序方式: 共有212条查询结果,搜索用时 15 毫秒
191.
Gulzar A. Bhat Sattwick Haldar Sonam Verma Debanjan Chakraborty Ramanathan Vaidhyanathan Ramaswamy Murugavel 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):17000-17005
Manipulation of low‐dimensional solids through soft chemical routes is an elegant way to realize newer materials. A new family of single‐crystalline transition‐metal layered organophosphates, with about 185 000 metal phosphate layers in a single crystal, can be exfoliated to a single‐layer nanosheet by a facile and rapid solvent assisted method. This exfoliation aids the formation of high‐surface‐area pyrophosphates with enhanced supercapacitance. 相似文献
192.
Banerjee AL Tobwala S Haldar MK Swanson M Roy BC Mallik S Srivastava DK 《Chemical communications (Cambridge, England)》2005,(20):2549-2551
A novel strategy of blocking the active site accessibility of MMP-9 by "multi-prong" surface binding groups is described. 相似文献
193.
Haldar J Aswal VK Goyal PS Bhattacharya S 《Journal of colloid and interface science》2005,282(1):156-161
The aggregation properties of single-chain surfactants bearing one (H1), two (H2), and three (H3) trimethylammonium head groups have been studied by small-angle neutron scattering (SANS). Growth of aggregates was observed to decrease dramatically with an increase in the number of head groups in the surfactants. The micelles grow progressively smaller with every increase in the number of head groups of the surfactants. Aggregation number (N) continuously decreases and the fractional charge (alpha) gradually increases with the increase in the number of head groups. The semiminor axis (a) and semimajor axis (b=c) of the micelle decrease strongly with the increase in the number of head groups. In the case of H1, dramatic micellar growth is observed on addition of salts such as KBr and sodium salicylate, but this type of micellar growth is not observed in the cases of H2 and H3 when the above salts are added to their micellar solutions. Aggregation number and size of the micelles remain almost the same, even after addition of KBr at a concentration as high as 100 mM. This observation with multiheaded cationic surfactants is unusual. Clearly, the charge density at the head group level of surfactants markedly influences their micellar aggregation properties. 相似文献
194.
C. Mamaloukas K. Haldar H. P. Mazumdar 《Journal of Applied Mathematics and Computing》2002,10(1-2):193-207
The present investigation deals with the pulsatile flow of incompressible viscous fluid through a circular rigid tube provided with constriction. The method applied here is the Decomposition Method, which has been developed by George Adomian [3]. The advantages of this method are the avoidance of simplifications and restrictions, which change the non-linear problem to mathematically tractable one, whose solution is not consistent with physical solution. Theoretically results, such as, wall shear stress and axial velocity component, have been obtained and the graphical solutions of these theoretical results have been shown in the figures. 相似文献
195.
Di-8-hydroxyquinolinium oxopentachloromolybdate(V) (OxineH)2[MoOCl5] (where Oxine = 8-hydroxyquinoline) has been isolated in pure state and has been characterised by chemical analysis, oxidation state determination, magnetic measurement, spectroscopic investigation and conductivity measurements. 相似文献
196.
Arijit BanerjeeSamir Kumar Maji Michael G.B. DrewDebasish Haldar Arindam Banerjee 《Tetrahedron letters》2003,44(35):6741-6744
Single crystal X-ray diffraction studies of a terminally blocked tripeptide Boc-Leu(1)-Aib(2)-Leu(3)-OMe 1 demonstrates that it adopts a bend structure without any intramolecular hydrogen bond. Peptide 1 self-assembles to form a supramolecular antiparallel β-sheet structure by various non-covalent interactions including intermolecular hydrogen bonds in the crystal and it exhibits amyloid-like fibrillar morphology in the solid state. 相似文献
197.
Ethylene diammonium oxopentachloro molybdate(V) enH2 [MoOCl5] (where en = ethylene diammine) has been isolated in pure state and has been characterised by chemical analysis, oxidation state determination, magnetic measurement, spectroscopic investigations and conductivity measurements. Its reactions have been studied in solution and solid state. 相似文献
198.
Mallick A Haldar B Chattopadhyay N 《Journal of photochemistry and photobiology. B, Biology》2005,78(3):215-221
Steady state absorption and fluorometric techniques have been used to investigate the photophysics of norharmane (NHM), a bioactive fluorophore, in aqueous as well as aqueous cyclodextrin (CD) environments. The absorption and steady state fluorescence spectral studies reveal the formation of two types of inclusion complexes between the fluorophore and beta-cyclodextrin (beta-CD) depending on the relative population of the two. The stoichiometries and association constants of these complexes have been determined monitoring the fluorescence data. alpha-and gamma-cyclodextrin (alpha-CD, gamma-CD) do not have appreciable effect on the spectral pattern of the fluorophore. The differential fluorimetric behavior of NHM in different CD environments has been rationalized from the variation of the relative dimensions of the probe and the CD cavities. 相似文献
199.
Dr. Stefan M. Marschner Dr. Ritesh Haldar Dr. Olaf Fuhr Prof. Dr. Christof Wöll Prof. Dr. Stefan Bräse 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1390-1401
Differently functionalized porphyrin linkers represent the key compounds for the syntheses of new porphyrin-based metal–organic frameworks (MOFs), which have gathered great interest within the last two decades. Herein we report the synthesis of a large range of 5,15-bis(4-ethoxycarbonylphenyl)porphyrin derivatives, through Suzuki and Sonogashira cross-coupling reactions of an easily accessible corresponding meso-dibrominated trans-A2B2-porphyrin with commercially available boronic acids or terminal alkynes. The resulting porphyrins were fully characterized through NMR, MS, and IR spectroscopy and systematically investigated through UV/Vis absorption. Finally, selected structures were saponified to the corresponding carboxylic acids and subsequently proven to be suitable for the synthesis of surface-anchored MOF thin films. 相似文献
200.
A simple glycosylation strategy employing only allyl glycosides is described. In a one-pot fashion, an allyl glycoside is first isomerized to the reactive 1-prop-en-yl glycoside intermediate, which subsequently undergoes glycosylation with a glycosyl acceptor, promoted by NIS at room temperature. 相似文献