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541.
Rakesh Kumar Mahajan Pallavi Sood Mohinder Pal Mahajan Parvesh Singh 《Analytical sciences》2004,20(10):1423-1426
A silver ion-selective electrode was prepared with a polymeric membrane incorporating 2,6-bis-methylsulfanyl-[1,3,5]thiadiazine-4-thione as an ionophore, tri-n-butylphosphate (TBP) as a plasticizer and sodium tetraphenylborate (NaTPB) as an additive. The electrode exhibited a near-Nernstian response of 52 mV/decade over a wide linear concentration range of 1.0 x 10(-5) - 1.0 x 10(-1) M with a lower detection limit of 9.77 x 10(-6) M. The electrode exhibited excellent selectivity for silver ion over many of the alkali, alkaline-earth and transition metal ions. The electrode worked well over a wide pH range of 1.77 - 7.13. The response time of the electrode was less than 20 s. The sensor can be applied as indicator electrode for the potentiometric titration of Ag+ ions with Cl- ions. 相似文献
542.
Ohne Zusammenfassung 相似文献
543.
The basic role of the representation of the gauge group in characterizing the topological excitations of the vacuum is pointed out. For SU(N) gauge fields on a lattice, the topological excitations are monopoles in the adjoint representation of the dual group 1SU(N). This leads to a dual representation of the Yang-Mills-Higgs system in 2 + 1 dimensions. For SU(3) the deal theory in a scalar theory with discrete Weyl symmetry S3. In the presence of adjoint Higgs fields the Weyl symmetry is broken in the Higgs phase but restored by pseudo-particles in the confinement phase. 相似文献
544.
I. K. Mehta D. S. Sood B. N. Misra 《Journal of polymer science. Part A, Polymer chemistry》1989,27(1):53-62
Acrylonitrile (AN) has been graft copolymerized onto isotactic polypropylene (IPP) by the preirradiation method using Co60 as the source of gamma rays in the presence of ethanol, n-propanol, isopropanol, n-butanol, tert. butyl alcohol, and n-pentanol. Alcohols vary in their ability to influence grafting of AN onto IPP and the following reactivity order was found: n-pentanol > n-butanol > tert.-butanol > n-propanol > ethanol > isopropanol. An attempt has been made to explain the observed reactivity pattern shown by different alcohols. Thermal behavior of the graft copolymer has been compared with that of IPP and irradiated IPP and it was observed that grafted IPP is thermally more stable than IPP and irradiated IPP. 相似文献
545.
546.
Supriya Dey Sumit O. Bajaj Tsung-I. Tsai Hong-Jay Lo Kevin Wu Chi-Huey Wong 《Tetrahedron》2018,74(41):6003-6011
Glycosyl phosphates are known as versatile donors for the synthesis of complex oligosaccharides both chemically and enzymatically. Herein, we report the stereoselective construction of modular building blocks for the synthesis of N-glycan using glycosyl phosphates as donors. We have synthesized four trisaccharide building blocks with orthogonal protecting groups, namely, Manβ2GlcNAc(OAc)3β6GlcNAc (9), Manβ2GlcNAc-β6GlcNAc(OAc)3 (15), Manβ2GlcNAc(OAc)3β4GlcNAc (18) and Manβ2GlcNAcβ4GlcNAc(OAc) (22) for further selective elongation using glycosyltransferases. The glycosylation reaction using glycosyl phosphate was found to be high yielding with shorter reaction time. Initially, The phthalimide protected glucosamine donor was exploited to ensure the formation of β-glycosidic linkage and later converted to the N-acetyl group before the enzymatic synthesis. The selective deprotection of O-benzyl group was performed prior to enzymatic synthesis to avoid its negative interference. 相似文献
547.
Kumar Ajay Vij Raman Sharma Sumit Sarin Amit 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):495-506
In this investigation, the passive estimation of radon (Rn222), thoron (Rn220) and their progenies have been measured in the dwellings of Reasi district of Jammu & Kashmir for a period of 1 year. These estimations have been done with the help of latest developed single entry Pin-hole based dosimeters and progeny sensors based on deposition. The annual Equilibrium factors for 222Rn, 220Rn, and their progenies have been calculated separately for each dwellings The average annual effective dose was found to be 0.9 ± 0.2 mSv/y for 222Rn, which is less than prescribed limit of ICRP. The results obtained indicate no vital health hazards because of exposure of Rn222, Rn220 and their progenies.
相似文献548.
Kateryna Vus Valeriya Trusova Galyna Gorbenko Rohit Sood Elena Kirilova Georgiy Kirilov Inta Kalnina Paavo Kinnunen 《Journal of fluorescence》2014,24(2):493-504
A series of novel fluorescent benzanthrone dyes have been tested for their ability to identify and characterize fibrillar aggregates of lysozyme prepared by protein denaturation in concentrated ethanol solution (Feth) or acidic buffer (Fac). Quantitative parameters of the dye association with native and fibrillar protein have been derived from the results of fluorimetric titration. The binding characteristics proved to be different for Feth- and Fac-bound benzanthrones, highlighting the dye sensitivity to the distinctions in fibril morphology. By comparing the dye preference to fibrillar protein aggregates, AM2, A8 and A6 were selected as the most prospective amyloid tracers. Based on the analysis of red edge excitation shifts and fluorescence lifetimes of the amyloid-bound dyes it was assumed that surface grooves or dry “steric zipper” interface are potential fibril binding sites for the novel fluorophores. 相似文献
549.
Mike JF Nalwa K Makowski AJ Putnam D Tomlinson AL Chaudhary S Jeffries-El M 《Physical chemistry chemical physics : PCCP》2011,13(4):1338-1344
Herein we report the synthesis of two solution processible, conjugated polymers containing the benzobisoxazole moiety. The polymers were characterized using (1)H NMR, UV-Vis and fluorescence spectroscopy. Thermal gravimetric analysis shows that the polymers do not exhibit significant weight loss until approximately 300 °C under nitrogen. Cyclic voltammetry shows that the polymers have reversible reduction waves with estimated LUMO levels at -3.02 and -3.10 eV relative to vacuum and optical bandgaps of 2.04-2.17 eV. Devices based on blends of the copolymers and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) exhibited modest power conversion efficiencies. Theoretical models reveal that there is poor electron delocalization along the polymer backbone, leading to poor performance. However, the energy levels of these polymers indicate that the incorporation of benzobisoxazoles into the polymer backbone is a promising strategy for the synthesis of new materials. 相似文献
550.
A novel and efficient method for the synthesis of a new variety of methylsulfanylpyrimidines by the reaction of dimethyl N‐cyanodithioiminocarbonate with substituted hydrazides. The synthetic potential of the method is demonstrated. 相似文献