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991.
M. L. Chauhan B. K. Patel S. N. Pandya A. V. Doshi 《Molecular Crystals and Liquid Crystals》2016,625(1):47-54
A novel ester homologous series of thermotropic liquid crystal (LC) has been studied with a view to understanding and establishing the relation between LC property and the molecular structure. The series consists of 11 members, the C1–C5 and C16 members of the series are nonliquid crystals. LC properties commence from the C6 homolog and continue up to the C14 homolog as enantiotropic nematic and smectic in addition to nematic. Transition temperatures of the homologs were determined by an optical polarizing microscope equipped with a heating stage. Textures of nematic phase are threaded or Schlieren and that of smectic is focal conic of the type-A. Analytical and spectral data confirm the structures of homologs. Thermal stability for nematic is 93 °C and 136 °C, respectively. The N–I and Sm–N transition curves of phase diagram do not exhibit odd-even effect. The N–I transition curve partly behaves in an abnormal manner. The Cr–I and Sm–N transition curves behave in normal manner. The LC behavior of the present series is compared with structurally similar known homologous series. 相似文献
992.
Liquid-crystalline elastomers (LCEs) possess large and equilibrium reversible anisotropic dimensional change in response to applied stimuli. The deformation behavior demonstrated by current LCE materials under the stimuli are generally determined by their own geometries and the alignment distributions of liquid crystal (LC) units in the LCE matrices. Here we report a LCE whose synthesis was through a two-stage crosslinking coupled with a mechanical reshaping process, where the shape was mechanically reset before the final crosslinking. It demonstrated reversible memory and change between the initial geometries formed during the first crosslinking stage and any reshaped geometries under the stimuli. Its deformation is not influenced by the geometries and the alignment distributions of LC units in the LCE matrix. This characteristic in LCEs holds promise in a wide range of application researches requiring sophisticated functions and smart structures. 相似文献
993.
James C. Kaczmarek Asha K. Patel Kevin J. Kauffman Owen S. Fenton Matthew J. Webber Michael W. Heartlein Frank DeRosa Daniel G. Anderson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(44):14012-14016
Therapeutic nucleic acids hold great promise for the treatment of disease but require vectors for safe and effective delivery. Synthetic nanoparticle vectors composed of poly(β‐amino esters) (PBAEs) and nucleic acids have previously demonstrated potential utility for local delivery applications. To expand this potential utility to include systemic delivery of mRNA, hybrid polymer–lipid nanoformulations for systemic delivery to the lungs were developed. Through coformulation of PBAEs with lipid–polyethylene glycol (PEG), mRNA formulations were developed with increased serum stability and increased in vitro potency. The formulations were capable of functional delivery of mRNA to the lungs after intravenous administration in mice. To our knowledge, this is the first report of the systemic administration of mRNA for delivery to the lungs using degradable polymer–lipid nanoparticles. 相似文献
994.
995.
Quantitation of acotiamide in rat plasma by UHPLC‐Q‐TOF‐MS: method development,validation and application to pharmacokinetics 下载免费PDF全文
Prinesh N. Patel Pradipbhai D. Kalariya Challa Veerabhadra Swamy S. Gananadhamu R. Srinivas 《Biomedical chromatography : BMC》2016,30(3):363-368
A novel, sensitive and selective ultra‐high‐performance liquid chromatography–electrospray ionization mass spectrometry method was developed and validated for the quantification of acotiamide (ACT), a first‐in‐class drug used in functional dyspepsia, in rat plasma. A simple protein precipitation method with acetonitrile as precipitating solvent was used to extract ACT from rat plasma. ACT and an internal standard (mirabegron, IS) were separated on an Agilent poroshell EC C18 column (50 × 3.0 mm, 2.7 µm) using methanol–10 mM ammonium acetate binary gradient mobile phase at a flow rate of 0.4 mL/min over 4 min run time. Detection was performed using target ions of [M + H]+ at m/z 451.2010 for ACT and m/z 397.1693 for IS in selective ion mode. The method was validated in the calibration range of 1.31–1000 ng/mL. All the validation parameters were well within the limits. The method demonstrated good performances in terms of intra‐ and inter‐day precision (3.27–12.60% CV) and accuracy (87.96–104.94%). Thus the present ultra‐high‐pressure liquid chromatograhy–high‐resolution mass spectrometry method for determination of ACT in rat plasma, is highly sensitive and rapid with a short run‐time of 4 min, can be suitable for high sample throughput and for large batches of biological samples in pharmacokinetic studies. This method can be extended to measure plasma concentrations of ACT in humans to understand drug metabolism, drug interaction and adverse effects. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
996.
Aninda Jiban Bhattacharyya Monalisa Patel Shyamal Kumar Das 《Monatshefte für Chemie / Chemical Monthly》2009,9(4):1001-1010
Abstract
Soft matter provides diverse opportunities for the development of electrolytes for all solid state lithium batteries. Here we review soft matter solid electrolytes for lithium batteriesthat are primarily obtained starting from liquid electrolytic systems. This concept of solid electrolyte synthesis from liquid is significantly different from prevalent approaches. The novelty of our approach is discussed in the light of various fundamental issues and in relation to its application to rechargeable lithium batteries. 相似文献997.
In continuation of the work in connection with the synthesis and characterization of polyketoetheresters [1], the present paper describes the synthesis of structurally related polyketoetheresters in which the ether linkage is in the acid moiety of the repeat unit. The polyesters listed in Table 1 were prepared by polycondensation of equimolar amounts of 4,4′-dicarboxyacetyldiphenyl ether (DCADPE) and the required diacetate of dihydroxyarenes and/or of the dimethyl ester of DCADPE and the required aliphatic diol or arene diol in the presence of zinc acetate. 相似文献
998.
Ketan D. Patel Forum C. Bhanshali Avani V. Chaudhary Sanjay S. Ingle 《Applied biochemistry and biotechnology》2013,170(1):58-66
New or more efficient methodologies having different principles are needed, as one method could not be suitable for isolation of organisms from samples of diverse types and from various environments. In present investigation, growth kinetics study revealed a higher germination rate, a higher growth rate, and maximum sporulation of Bacillus thuringiensis (Bt) compared to other Bacillus species. Considering these facts, a simple and efficient enrichment method was devised which allowed propagation of spores and vegetative cells of Bt and thereby increased Bt cell population proportionately. The new enrichment method yielded Bt from 44 out of 58 samples. Contrarily, Bt was isolated only from 16 and 18 samples by sodium acetate selection and dry heat pretreatment methods, respectively. Moreover, the percentages of Bt colonies isolated by the enrichment method were higher comparatively. Vegetative whole cell protein profile analysis indicated isolation of diverse population of Bt from various samples. Bt strains isolated by the enrichment method represented novel serovars and possibly new cry2 gene. 相似文献
999.
Poly-Schiff-base ligand (SBSAL-DDM) is synthesized by condensing bis-salicylaldehyde 5,5′-sulfone with 4,4′-diaminodiphenyl methane. The polychelates of Cu(II), Ni(II), Co(II), and Mn(II) with poly-Schiff base have been isolated and analyzed. The analytical data agree with 1:1 metal-ligand stoichiometry. The polychelates are studied in terms of electrical, thermal, spectral, and magnetic properties. A probable structure has been proposed for the above polymers. 相似文献
1000.
Himatkumar V. Patel Kavita A. Vyas Sudhanshu P. Pandey Francis Tavares P. S. Fernandes 《合成通讯》2013,43(18-19):1935-1940
A one-pot synthesis of 5,6-disubstituted-2-phenyl-3(2H)-pyridazinones 4 is achieved on treatment of carbanion of ethyl trimethlsiylacetate with phenylhydrazones of 1,2-dicarbonyl compounds 1. 相似文献