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61.
Dr.Chakraborty S 《橡胶工业》1997,(12):732-733
一种高效又经济的混炼方法———在配方中添加塑解剂AcimelDr.ChakrabortyS(ICIIndiaLimited)橡胶是一种弹性体,相对分子质量比较高,在加工温度下有较高的粘度。若不加入配合剂,橡胶本身是无法使用的。由于要加入的配合剂大多... 相似文献
62.
Broadband dielectric spectroscopy of Nafion‐117, sulfonated polysulfone (sPSF) and sulfonated polyether ketone (sPEK) membranes 下载免费PDF全文
Wasim F. G. Saleha Rahul Ramesh Naresh Nalajala Arup Chakraborty Bradley P. Ladewig Manoj Neergat 《应用聚合物科学杂志》2017,134(18)
Nafion®‐117, sulfonated polysulfone (sPSF) and sulfonated polyetherketone (sPEK) are characterized using broadband dielectric spectroscopy in the frequency range of 10 MHz–100 mHz. Overall, there are 4–5 relaxation processes in these sulfonated membranes and a comparison of their spectral features allows assigning the relaxation processes. At an optimum amplitude of ~100 mVrms, all the relaxations are clearly defined as the electrode polarization is minimized. At low temperatures (?130 °C), these membranes show a broad relaxation peak in the mid‐frequency region, which quickly shifts towards the high‐frequency region as the temperature is increased to ?90 °C. This peak is observed in proton exchange membranes for the first time due to the use of low ac amplitude, and it is assigned to the relaxation of the confined water in the micro‐pores. With all the membranes, the peak associated with ? SO3H group relaxation is observed in the same frequency range at a temperature of ~?80 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44790. 相似文献
63.
Manjima Bhattacharya Riya Chakraborty Arjun Dey Ashok Kumar Mandal Anoop Kumar Mukhopadhyay 《Ceramics International》2013,39(2):999-1009
The present experiments were focused on nanoindentation behaviour and the attendant “micro-pop-in” in a dense (~95% of theoretical) coarse-grain (~20 μm) alumina ceramic as a function of loading rate variations at three constant peak loads in the range of 105–106 μN. Based on the experimental results here we report for the first time, to the best of our knowledge, an increase in intrinsic nano scale contact resistance as well as the nanohardness with the loading rate. These observations were explained in terms of the correlation between the nanoscale plasticity and shear stress active just underneath the nanoindenter. 相似文献
64.
Semi1 and semi2 interpenetrating polymer networks (IPNs) of PVC and in situ formed PMMA have been synthesized using diallyl phthalate and ethylene glycol dimethacrylate as the crosslinkers of PVC and PMMA, respectively. These two types of IPNs have been compared w.r.t their physical, mechanical, and thermal properties and an endeavor has been made to find a correlation of these properties with the morphology generated in these systems. The semi1 IPNs displayed a decrease in their mechanical parameters and the physical properties as well, while in contrast, the semi2 IPNs exhibited a marginal increase in the corresponding values after an initial drop upto about 15% of crosslinked PMMA incorporation when compared to the crosslinked PVC in the case of semi1 IPN and linear PVC in the case of semi2 IPN. The various samples of semi1 and semi2 IPNs showed a two‐stage degradation typical of PVC, while confirming the increased stability with the samples having higher percentages of PMMA. The influence of crosslinking of the major matrix in semi1 IPN was almost counterbalanced by the influence of crosslinking in the dispersed PMMA phase in the case of semi2 IPN. The softening characteristics as detected by the extent of penetration of the probe, as has been detected by thermomechanical analysis, are in conformity with their mechanicals. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1725–1735, 2005 相似文献
65.
Santanu Basu Amitava Chakraborty Parukuttyamma Sujatha Devi Himadri Sekhar Maiti 《Journal of the American Ceramic Society》2005,88(8):2110-2113
Nanocrystalline La0.9 Sr0.1 Al0.85 Co0.05 Mg0.1 O3 oxide powder was synthesized by a citrate–nitrate auto-ignition process and characterized by thermal analysis, X-ray diffraction, and impedance spectroscopy measurements. Nanocrystalline (50–100 nm) powder with perovskite structure could be produced at 900°C by this process. The powder could be sintered to a density more than 96% of the theoretical density at 1550°C. Impedance measurements on the sintered samples unequivocally established the potential of this process in developing nanostructured lanthanum aluminate-based oxides. The sintered La0.9 Sr0.1 Al0.85 Co0.05 Mg0.1 O3 sample exhibited a conductivity of 2.40 × 10−2 S/cm in air at 1000°C compared with 4.9 × 10−3 S/cm exhibited by La0.9 Sr0.1 Al0.85 Mg0.15 O3 . 相似文献
66.
N. R. Manoj P. Sivaraman S. Praveen R. D. Raut L. Chandrasekhar B. C. Chakraborty 《应用聚合物科学杂志》2005,97(5):1763-1770
Ternary blends of thermoplastic polyurethane and a poly(vinyl chloride)/nitrile rubber blend were investigated in this work. The blends, with weight ratios of 100/0, 80/20, 40/60, 60/40, 80/20, and 0/100, were prepared via melt blending. Dynamic mechanical analysis showed that the blends with ratios of 20/80 and 80/20 were miscible, whereas the 40/60 and 60/40 blends were partially miscible. IR spectroscopy studies showed shifts in the peaks due to specific interactions in the blends. The blends showed degradation behavior between the blend components. The fracture toughness was investigated with the J‐integral by the locus method; the components and the miscible blends had good fracture toughness, whereas the other blends had lower toughness. Similar behavior was observed for the tensile properties. Scanning electron microscopy studies showed the morphological variations in the blends. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1763–1770, 2005 相似文献
67.
Ajith Kumar K. K. Srinivasan A. Pillai U. T. S. Pai B. C. Chakraborty M. 《SILICON》2022,14(15):9499-9515
Silicon - The present work aims at understanding the microstructure and mechanical property correlation of hypo (Mg-0.5, 0.7, 1.15 wt% Si) and hyper (Mg-2, 4, 6, 8 and 10 wt% Si) eutectic binary... 相似文献
68.
Sarbani Ghoshal Sandip Mukherjee Molee Chakraborty Eliwaza Naomi Msengi Jake Haubner Anutosh Chakraborty 《International journal of molecular sciences》2022,23(4)
(1) Background: We previously demonstrated that disruption of IP6K1 improves metabolism, protecting mice from high-fat diet-induced obesity, insulin resistance, and non-alcoholic fatty liver disease and steatohepatitis. Age-induced metabolic dysfunction is a major risk factor for metabolic diseases. The involvement of IP6K1 in this process is unknown. (2) Methods: Here, we compared body and fat mass, insulin sensitivity, energy expenditure and serum-, adipose tissue- and liver-metabolic parameters of chow-fed, aged, wild type (aWT) and whole body Ip6k1 knockout (aKO) mice. (3) Results: IP6K1 was upregulated in the adipose tissue and liver of aWT mice compared to young WT mice. Moreover, Ip6k1 deletion blocked age-induced increase in body- and fat-weight and insulin resistance in mice. aKO mice oxidized carbohydrates more efficiently. The knockouts displayed reduced levels of serum insulin, triglycerides, and non-esterified fatty acids. Ip6k1 deletion partly protected age-induced decline of the thermogenic uncoupling protein UCP1 in inguinal white adipose tissue. Targets inhibited by IP6K1 activity such as the insulin sensitivity- and energy expenditure-inducing protein kinases, protein kinase B (PKB/Akt) and AMP-activated protein kinase (AMPK), were activated in the adipose tissue and liver of aKO mice. (4) Conclusions: Ip6k1 deletion maintains healthy metabolism in aging and thus, targeting this kinase may delay the development of age-induced metabolic dysfunction. 相似文献
69.
Polypropylene was melt blended in a single screw extruder with thermo tropic Vectra B‐950 liquid crystalline polymer (copolyester amide) in different proportions in presence of 2% of EAA, ethylene‐acrylic acid copolymer (based on PP) as a compatibilizer. The mechanical properties of such compatibilized blends were evaluated and compared in respect of their Young's Modulii, Ultimate tensile strength, percent elongation at break, and toughness to those of Pure PP. The Morphology was studied by using a polarizing light microscope (PLM) and Scanning electron microscope (SEM). The Thermal characterization of these blends were carried out by differential scanning calorimeter (DSC).The mechanical properties under dynamic conditions of such compatibilized blends and pure PP were studied by dynamic mechanical analyzer (DMA). Mechanical analysis (Tensile properties) of the compatibilized blends displayed improvements in Modulii and ultimate tensile strength (UTS) of PP matrix with the incorporation of 2–10% of LCP incorporation. The development of fine fibrillar morphology in the compatibilized PP/LCP blends had large influence on the mechanical properties. Differential scanning calorimeter (DSC) studies indicated no remarkable changes in the crystalline melting temperature of the blends with respect to that of pure PP. However, an increase in the softening range of the blends over that of PP was observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
70.
Bamboo strips [10 cm × 1.5 cm × (1?1.5) mm] were treated with caustic solutions for 1 h at different concentrations e.g., 0, 10, 15, 20, and 25%. Bamboo strips reinforced polyester resin composites were fabricated by hand‐lay‐up technique using both alkali‐treated and untreated bamboo strips, using a room temperature curing system for the polyester resin. This study aims at the evaluation of the influence of caustic concentration on the mechanical properties of bamboo strips reinforced polyester resin composites at a constant 50% loading of reinforcement. Maximum improvement in property was achieved possibly with 20% of caustic treated strip reinforcements. Beyond 20%, there was degradation in all the strength properties because of failure in mechanical properties of the reinforcements itself. The effect of fiber loading variation upon mechanical properties was also studied. It was observed that superior mechanical properties were obtained with 60% filler loading. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献