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51.
The present study investigates the effect of hybrid fillers such as graphene nanoplatelets (GnPs) and Titanium di-oxide (TiO2) in polypropylene (PP) composites on the mechanical properties. The compatibilizing agent of Maleic anhydride grafted polypropylene (MAPP) are used in the polypropylene based composites to increase the interfacial adhesion between matrix and fillers. The experiments are designed according to L16 orthogonal array (OA) based design of experiments (DOE). The parameters selected for this study are GnPs, TiO2 and MAPP with four different levels are used.By using Orthogonal array and Taguchi based experimental design, the performance characteristics of tensile modulus, tensile strength, elongation at break and toughness can be analyzed with more objective through a small set of experiments.Taguchi based analysis are used to find out the optimal parameters to maximize the tensile properties for the GnPs and TiO2 reinforced PP hybrid composites. Further, analysis of variance (ANOVA) is investigated to identify the most significant parameters which influence the mechanical properties.From the analysis it was found that the optimal parameters of 3 ?wt% GnPs, 2 ?wt% TiO2 and 6 ?wt% MAPP for maximum tensile modulus and tensile strength. The most significant parameter for tensile modulus and tensile strength is GnPs followed by TiO2 and MAPP according to ANOVA analysis. 相似文献
52.
Patra Kankan Sengupta Arijit Mishra R. K. Mittal V. K. Valsala T. P. Kaushik C. P. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1473-1481
Journal of Radioanalytical and Nuclear Chemistry - Efficient and selective extraction of 137Cs and 90Sr from high level liquid waste (HLLW) is of utmost importance in the back end nuclear fuel... 相似文献
53.
Simon Sengupta Philipp Schüler Dr. Helmar Görls Dr. Phil Liebing Dr. Sven Krieck Prof. Matthias Westerhausen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(50):e202201359
The in situ Grignard Metalation Method (iGMM) is a straightforward one-pot procedure to quickly produce multigram amounts of Hauser bases R2N-MgBr which are valuable and vastly used metalation reagents and novel electrolytes for magnesium batteries. During addition of bromoethane to a suspension of Mg metal and secondary amine at room temperature in an ethereal solvent, a smooth reaction yields R2N-MgBr under evolution of ethane within a few hours. A Schlenk equilibrium is operative, interconverting the Hauser bases into their solvated homoleptic congeners Mg(NR2)2 and MgBr2 depending on the solvent. Scope and preconditions are studied, and side reactions limiting the yield have been investigated. DOSY NMR experiments and X-ray crystal structures of characteristic examples clarify aggregation in solution and the solid state. 相似文献
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55.
Souvik Sarkar Aritra Sarkar Prof. Dr. Subi J. George 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20013-20017
Stereoselective and temporally controlled supramolecular polymerizations are ubiquitous in nature and are desirable attributes for the design of chiral, well-defined functional materials. Kinetically controlled, living supramolecular polymerization (LSP) has emerged recently for the synthesis of supramolecular polymers with controlled length and narrow dispersity. On the other hand, stringent design requirements for chiral-discriminating monomers precludes the stereoselective control of the supramolecular polymer structure. Herein, a synergetic stereo- and structural control of supramolecular polymerization by the realization of an unprecedented stereoselective seed-induced LSP is reported. Homochiral and seeded growth is demonstrated with bischromophoric naphthalene diimide (NDI) enantiomers with a chiral binaphthyl amine core, exhibiting strong self-recognition abilities and pathway complexity. 相似文献
56.
Rajeswari B. Sengupta Arijit Kadam R. M. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):135-142
Journal of Radioanalytical and Nuclear Chemistry - The speciation of iodine in environment must be known in order to properly assess its geological fate and to study potential remediation materials... 相似文献
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A Kerr metric describing a rotating black hole is obtained on the three brane in a five-dimensional Randall-Sundrum brane
world by considering a rotating five-dimensional black string in the bulk. We examine the causal structure of this space-time
through the geodesic equations. 相似文献
60.
Raj K. Sehgal Sisir K. Sengupta R. Karl Dieter 《Journal of heterocyclic chemistry》1985,22(3):665-667
A single step synthesis of 2-deaminoactinomycin D ( 3a ) and 2-deamino-2-nitroactinomycin D ( 2a ) arising from actinomycin D ( 1a, AMD ) is reported. Structural confirmation was made by nmr, ir and chemical conversion to known materials. 相似文献