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排序方式: 共有375条查询结果,搜索用时 31 毫秒
71.
72.
Readouts that work autonomously on colorimetric principles were fabricated inside a microchannel by immobilizing dyes in a hydrogel matrix. Two pH-sensitive dyes (congo red and phenolphthalein) were studied. The response time of the readout varied between 20 s for phenolphthalein and 45 s for congo red dyes. The robustness of the dyed gels was tested at different flow rates (0.1, 0.25 and 0.5 mL min(-1)). Combinatorial readouts consisting of gels with the different dyes were fabricated and tested. Based on the limits of human perception, the fabrication methodology and the principles of functioning; general design rules for fabricating a readout device are discussed. The simple and low cost fabrication technique combined with autonomous functioning make the readout appropriate for portable microfluidic systems. 相似文献
73.
G. R. Dey D. B. Naik K. Kishore P. N. Moorthy 《Journal of Radioanalytical and Nuclear Chemistry》1992,163(2):391-400
Rate constants for the reaction of the primary species of water radiolysis, viz. e
aq'
–
, H and OH, with picolinic acid have been determined at various pHs. The semi-reduced species exhibits max at 305 and 350 nm. It is a strong reductant and has two pKa values of 1 and 5.7. The OH adduct of this compound also exhibits two pKa s at 2.1 and 5.2. H-atom reaction with picolinic acid gives rise to a mixture of species. 相似文献
74.
Lactols, which are insoluble or only sparingly soluble in most of the organic solvents that are generally employed for oxidation, are converted to lactones using o-iodoxybenzoic acid (IBX) in a facile manner under modified experimental conditions [EtOAc-DMSO (9:1) mixture at reflux] in good to excellent isolated yields (66-91%). 相似文献
75.
C.K. Vinayakumar G.R. Dey K. Kishore P.N. Moorthy 《Radiation Physics and Chemistry》1996,48(6):737-742
Reactions of eaq−, H-atoms, OH, (CH3)2COH, and CO2− radicals with V(III)picolinate and Cr(III)picolinate have been studied by the pulse radiolysis technique. The spectra of V(II)picolinate, V(IV)picolinate, Cr(II)picolinate, OH adduct of Cr(III)picolinate and Cr(IV)picolinate have been obtained and the rate constants of the reactions of various radicals with V(III) and Cr(III)picolinate have been determined. The implications of these results to the chemical decontamination of nuclear reactor systems are discussed. 相似文献
76.
Y Anjaneyulu R Prabhakar Rao R Y Swamy A Eknath K Narasimha Rao 《Journal of Chemical Sciences》1982,91(2):157-163
A series of mixed ligand complexes of Hg(II) with the general formula Hg (OX) (SA) (where OX: 8-hydroxyquinoline, SA: salicylic,
5-chloro-, 3,5-dibromo, 3,5-diiodo, 3,5-dinitro, acetyl thiosalicylic acids) are isolated in pure state and characterised
by elemental analysis and infrared data. The low molar conductance of the complexes in dimethylformamide indicates non-electrolyte
nature. The antimicrobial activity of these complexes against various bacteria and fungi is studied which indicates that in
several cases, the mixed ligand complexes possess fairly highly antimicrobial activity than the binary mercury-oxinate. The
lipophilic tendency of these complexes and its influence on the antimicrobial activity is critically examined. A probable
mechanism for the toxic action of these complexes against various organisms is discussed. 相似文献
77.
Helicenes as All‐in‐One Organic Materials for Application in OLEDs: Synthesis and Diverse Applications of Carbo‐ and Aza[5]helical Diamines 下载免费PDF全文
Samik Jhulki Abhaya Kumar Mishra Prof. Dr. Tahsin J. Chow Prof. Dr. Jarugu Narasimha Moorthy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9375-9386
A set of eight helical diamines were designed and synthesized to demonstrate their relevance as all‐in‐one materials for multifarious applications in organic light‐emitting diodes (OLEDs), that is, as hole‐transporting materials (HTMs), EMs, bifunctional hole transporting + emissive materials, and host materials. Azahelical diamines function very well as HTMs. Indeed, with high Tg values (127–214 °C), they are superior alternatives to popular N,N′‐di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPB). All the helical diamines exhibit emissive properties when employed in nondoped as well as doped devices, the performance characteristics being superior in the latter. One of the carbohelical diamines (CHTPA) serves the dual function of hole transport as well as emission in simple double‐layer devices; the efficiencies observed were better by quite some margin than those of other emissive helicenes reported. The twisting endows helical diamines with significantly high triplet energies such that they also function as host materials for red and green phosphors, that is, [Ir(btp)2acac] (btp=2‐(2′‐benzothienyl)pyridine; acac=acetylacetonate) and [Ir(ppy)3] (ppy=2‐phenylpyridine), respectively. The results of device fabrications demonstrate how helicity/ helical scaffold may be diligently exploited to create molecular systems for maneuvering diverse applications in OLEDs. 相似文献
78.
Rollinicin1 (I), uvaricin2 (II) and cherimoline3 (III), the new antitumour, antibiotic agents, isolated from renewable resources having bistetrahydrofuran ring system in the molecules, have been recently reported. Bates2 has postulated that uvaricin has been probably biosynthesised from 1,5,9-trienoic acid derivative. The central portion of I - III, a bistetrahydrofuran ring system, is apparently novel. This prompted us to develop a methodology for the construction of the central bistetrahydro-furan ring system (L) using acetylenic derivatives as the starting materials for the first time. In this communication, we report 4 its result. 相似文献
79.
80.
T. Janaki Rami Reddy V.B.S. Achari A.K. Sharma V.V.R. Narasimha Rao Ch.V. Subba Reddy 《Journal of Physics and Chemistry of Solids》2008,69(4):1033-1036
This paper presents results of the studies on ionic conductivity and transference number measurements on potassium chlorate (KClO3) complexed polyvinyl chloride (PVC) films prepared by solution-cast technique. Temperature dependence of ionic conductivity and transference number data indicated the dominance of ion-type charge transport in these specimens. The magnitude of conductivity increased with increase in the concentration of the salt and temperature. Using this (PVC+KClO3) electrolyte, solid-state electrochemical cells were fabricated and their discharge profiles were studied under a constant load of 100 kΩ. Several cell profiles associated with these cells were evaluated and are reported. 相似文献