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161.
Li Zhen Gong Wenli Chen Xuan Liu Lin Meng Ranju Ding Yanhong Yao Juming 《Cellulose (London, England)》2021,28(17):11097-11108
Cellulose - Green bio-flocculants from renewable biomass resources have received the widespread attention for wastewater treatment, which are promising alternatives to petroleum-based synthetic... 相似文献
162.
First principles calculations reveal that for Pd/TiAl interfaces the substitution of interface Ti atoms with Cr or V atoms is energetically favorable with negative heat of formation, and could bring about a very small increase of interface bond strength, while the interstitial Cr and V atoms should be unfeasible with highly positive heat of formation and would increase the bond lengths of interface Pd–Al and Pd–Ti bonds. Calculations also demonstrate that both Cr and V would induce an increase of interface energy, suggesting that the impurity atoms of Cr or V should be reduced to a minimum level, in order to get a thermally stable Pd/TiAl interface with a longer lifetime. In addition, it is found that the substitution of V at the Pd/TiAl interfaces should be much easier than that of Cr, which is in good agreement with similar experimental observations in the literature. 相似文献
163.
Attapulgite grafted with polystyrene via a simultaneous reverse and normal initiation atom transfer radical polymerization
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Haicun Yang Hongting Pu Fanghong Gong 《Journal of polymer science. Part A, Polymer chemistry》2016,54(11):1508-1516
The surface grafting of attapulgite (ATP) with polystyrene (PS) was established via a simultaneous reverse and normal initiation atom transfer radical polymerization (SR&NIATRP). 4‐(chloromethyl)phenyltrimethoxysilane (CMPTMS) chemical bounded on the surface of ATP (ATP‐Cl, Cl‐I) was prepared via one‐step self‐assembly. SR&NI ATRP of styrene was conducted using CuCl2 complex tris(2‐(dimethylamino)ethyl)amine (Me6‐TREN) as the catalytic system, initiated by 2,2‐azobis(isobutyronitrile) (AIBN) and ATP‐Cl. FT‐IR, XRD, XPS, TGA and TEM data were consistent with the grafting of benzyl chloride groups and PS chains on ATP surface. The controllability of polymerization was investigated by the kinetics behavior under different molar ratio of AIBN and CuCl2. The obtained polymer possessed a uniform distribution of molecular weights with a lower polydispersity index of 1.2~1.4. The relationship between polymerization on the surface of ATP and in solution was discussed in detail based on TGA data of hybrid particles and GPC trace of free polymer in solution. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1508–1516 相似文献
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Design and solid phase synthesis of the 1,3,4-oxadiazole based peptidomimetic library is presented. Library synthesis starts from the coupling of the thiosemicarbazide resin with Fmoc-protected amino acid following desulfurative cyclization to 1,3,4-oxadiazoles. Following substitution of the secondary amine with the 3-nitrobenzoyl functional group and its further reduction were performed. Thus, the functionalization with amino acids could be performed on both sides of the core skeleton. After diversification and cleavage from the resin using TFA: DCM cleavage cocktail, an enantiopure library of compounds was obtained. Further evaluation of physicochemical properties was performed. 相似文献
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Jin Kai Li Baowei Wang Kaixing Luo Huijuan Gong Zhijun Wu Wenfei 《Research on Chemical Intermediates》2018,44(11):6933-6943
Research on Chemical Intermediates - A rare-earth concentrate obtained from Bayan Obo tailings was used as catalyst for low-temperature selective catalytic reduction (SCR) of NOx. X-ray powder... 相似文献
169.
Annealing polyethylene terephthalate (PET)/polycarbonate (PC) blends enhance the transesterification reaction and increase the amount of copolymer at the interface of both polymers. The copolymer enhances the compatibility of PET with PC, because it contains both PET and PC blocks, which causes the interface between PET and PC to become fuzzy. When the PET/PC undergoes batch physical foaming with CO2, the copolymer significantly changes the resulting cell morphology, that is, the annealing time. Before annealing or in the absence of the copolymer, bubble nucleation occurs and dominates growth at the interface. When the PET/PC blends are annealed, the interface impedes bubble nucleation and growth. The polymer is stretched at the interface by bubble growth, forming fibril‐like structures connecting two polymer domains at the interface. Increased annealing time causes the interface to become more homogeneous and makes heterogeneous bubble nucleation difficult. At higher copolymer concentrations, the interface of PET and PC becomes fuzzy and the cell morphology becomes like those of foamed homogeneous polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
170.