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1.
Das Pritam Kumar Mallik Arnab Kumar Molla Altaf Hossain Santra Apurba Kumar Ganguly Ranjan Saha Abhijit Kumar Sugam Aswal V. K. 《Journal of Thermal Analysis and Calorimetry》2022,147(10):5617-5635
Journal of Thermal Analysis and Calorimetry - Nanofluids have gained recent attention because of their potential applications in diverse engineering fields like enhancing thermal transport,... 相似文献
2.
Savita Verma Deepak M. Maher Samadhan S. Nagane Bhausaheb V. Tawade Prakash P. Wadgaonkar 《Journal of polymer science. Part A, Polymer chemistry》2019,57(5):588-597
New aromatic (co)polyesters containing pendant propargyloxy groups were synthesized by phase transfer‐catalyzed interfacial polycondensation of 5‐(propargyloxy)isophthaloyl chloride (P‐IPC) and various compositions of P‐IPC and isophthaloyl chloride with bisphenol A. FTIR and NMR spectroscopic data, respectively, revealed successful incorporation of pendant propargyloxy groups into (co)polyesters and formation of (co)polyesters with desired compositions. (Co)polyesters exhibited good solubility in common organic solvents such as chloroform, dichloromethane, and tetrahydrofuran and could be cast into transparent, flexible, and tough films from chloroform solution. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.77–1.33 dL/g and 43,600–118,000 g/mol, respectively, indicating the achievement of reasonably high‐molecular weights. The 10% weight loss temperatures of (co)polyesters were in the range 390–420 °C, demonstrating their good thermal stability. (Co)polyesters exhibited Tg in the range 146–170 °C and Tg values decreased with increase in mol % incorporation of P‐IPC. The study of non‐isothermal curing by DSC indicated thermal crosslinking of (co)polyesters via propargyloxy groups. The utility of pendant propargyloxy group was demonstrated by post‐modification of the selected copolyester with 1‐(4‐azidobutyl)pyrene, 9‐(azidomethyl)anthracene, and azido‐terminated poly(ethyleneglycol) monomethyl ether via copper(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition reaction. FTIR and 1H NMR spectra confirmed that click reaction was quantitative. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 588–597 相似文献
3.
Partially supported by the general research fund at the University of Kansas 相似文献
4.
Prashant M. Bhatt Gautam R. Desiraju 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o362-o363
The title compound [systematic name: 8‐chloro‐11‐(piperidin‐4‐ylidene)‐6,11‐dihydro‐5H‐benzo[4,5]cyclohepta[2,1‐b]pyridine], C19H19ClN2, was crystallized from ethyl acetate. The interesting feature of the reported structure is that it does not contain any strong hydrogen bonds, although the molecule contains a secondary NH group, which is a good hydrogen‐bond donor. 相似文献
5.
We present a characterization of confluence for term rewriting systems, which is then refined for special classes of rewriting systems. The refined characterization is used to obtain a polynomial time algorithm for deciding the confluence of ground term rewrite systems. The same approach also shows the decidability of confluence for shallow and linear term rewriting systems. The decision procedure has a polynomial time complexity under the assumption that the maximum arity of a function symbol in the signature is a constant. 相似文献
6.
7.
Cyclic voltammetric studies of certain industrially potential iron chelate catalysts 总被引:1,自引:0,他引:1
For the analysis of infrared spectroscopic bands and complex patterns partial cross correlation functions of a sample spectrum
with reference spectra are calculated. The chosen ranges of the spectra are based on empirical knowledge of infrared spectrum
structure correlations. The normalised maxima of the partial cross correlation functions are interpreted as fuzzy truth values
and are combined by fuzzy logical operators. By application of that procedure larger common substructures will be derived
from the reference spectra than by a maximum common substructure search based on the complete spectra.
Received: 30 October 1996/Revised: 24 February 1997/Accepted: 26 February 1997 相似文献
8.
Xiao Huang Bishwa Ranjan Nayak Tao Lu Lowe 《Journal of polymer science. Part A, Polymer chemistry》2004,42(20):5054-5066
A series of novel multifunctional hydrogels that combined the merits of both thermoresponsive and biodegradable polymeric materials were designed, synthesized, and characterized. The hydrogels were copolymeric networks composed of N‐isopropylacrylamide (NIPAAM) as a thermoresponsive component, poly(L‐lactic acid) (PLLA) as a hydrolytically degradable and hydrophobic component, and dextran as an enzymatically degradable and hydrophilic component. The chemical structures of the hydrogels were characterized by an attenuated total reflection–Fourier transform infrared spectroscopy (ATR–FTIR) technique. The hydrogels were thermoresponsive, showing a lower critical solution temperature (LCST) at approximately 32 °C, and their swelling properties strongly depended on temperature changes, the balance of the hydrophilic/hydrophobic components, and the degradation of the PLLA component. The degradation of the hydrogels caused by hydrolytic cleavage of ester bonds in the PLLA component was faster at 25 °C below the LCST than at 37 °C above the LCST, determined by the ATR–FTIR technique. Due to their multifunctional properties, the designed hydrogels show great potential for biomedical applications, including drug delivery and tissue engineering. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5054–5066, 2004 相似文献
9.
10.
In view of persisting discrepancy between experimental and theoretical results, specially in the weak radiative decays of∑ + andΞ 0, we analyse these decays within the framework of the QCD inspired quark-diquark model. On introducing a slightSU(6) breaking we obtainα(∑ +→p+γ)≈?0.9 which is in excellent agreement with experimental value. Other decays are also improved in this scheme. 相似文献