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51.
Nintu Mandal S. C. Datta K. M. Manjaiah B. S. Dwivedi R. Kumar P. Aggarwal 《Polymer-Plastics Technology and Engineering》2018,57(17):1760-1770
Novel zincated nanoclay polymer composites (ZNCPCs) with variable percentage of commercial bentonite and nanobentonite (8%, 10% and 12% of monomer for each case) were synthesized. Polyacrylic acid-Polyacrylamide copolymer was synthesized using N, N-Methylene bisacrylamide as crosslinker and ammonium persulfate as initiator. Clays as well as ZNCPCs were characterized by XRD, SEM, TEM and FTIR. 12% nanoclay containing formulation showed slowest release rate. ZNCPCs containing 8% clay recorded highest Zn content as well as highest equilibrium water absorbency. Biodegradation study revealed that Aspergillus spp was more effective as compared with Trichoderma spp in degradation of ZNCPCs. 相似文献
52.
Whole grains and resistant starch rich,reduced‐calorie biscuit diet as a hypoglycaemic,hypolipidaemic and insulin stimulator in streptozotocin‐induced diabetic rats 下载免费PDF全文
Dipesh Aggarwal Latha Sabikhi Heena Lamba Neha Chaudhary Rajeev Kapila 《International Journal of Food Science & Technology》2017,52(1):118-126
A fibre‐enriched, reduced‐calorie biscuit [formulated biscuit (FB)] was evaluated for its antidiabetic and antilipidaemic potential in streptozotocin‐induced diabetes in Wistar rats against control biscuit (CB) having high calorie and low fibre content. Animals were allocated into five groups: a control group fed with synthetic diet, two diabetes‐induced groups (CBD and FBD) and two nondiabetic groups (CBND and FBND). CBD and CBND were fed with synthetic diet + CB while FBD and FBND were fed with synthetic diet + FB. After 6 weeks of feeding, the change in weight of nondiabetic group fed with FB (+16.20%) was nonsignificantly lower compared to control (+33.01%) and CB‐fed (+34.55%) group. Nonsignificant loss in body weight was observed among diabetic group fed with FB (?11.76%) or CB (?36.88%). Feeding of FB led to a significant decrease in fasting and postprandial blood glucose levels, total cholesterol, triglycerides, LDL‐C, VLDL‐C and atherosclerotic index and increase the HDL‐C. Histological examination showed that feeding of FB was able to partially recover the destroyed β‐cell in STZ‐induced diabetic rats. 相似文献
53.
54.
The change in the absorption loss of IR-transmitting chalcogenide glass fibers in the temperature range of -90 degrees C = T = 70 degrees C was investigated. For sulfur-based glass fibers the change in loss relative to room temperature was slightly affected by the temperature in the wavelength region of 1-5 mum. For lambda >/= 6 mum the change in loss was mainly due to multiphonon absorption. The change in loss for tellurium-based glass fibers increased significantly at T = 60 degrees C. The increase in the loss at short wavelengths (lambda = 4.1 mum) was due to electronic excitations in the tail states. Between 5 and 9 mum there was noticeable free-carrier absorption. Beyond lambda >/= 9 mum, multiphonon absorption dominated the loss spectrum. 相似文献
55.
Guillermo R. Villalobos Shyam S. Bayya Jasbinder S. Sanghera Robert E. Miklos Frederic Kung Ishwar D. Aggarwal 《Journal of the American Ceramic Society》2002,85(8):2128-2130
A spray drying approach was used to apply 15-nm-thick SiO2 continuous coatings onto ZnS:Ag phosphor particles. A prehydrolyzed TEOS dip coating formula was used as the SiO2 precursor. The phosphor was mixed together with the precursor then atomized without allowing gelation to occur until the droplets containing the particles were in flight. The coating gelled and dried while falling through a graded heat zone. The dried coated particles were captured in a cyclone separator and heat-treated to further densify the SiO2 coating. The coatings protected the phosphors while in service in field emission display (FED) devices. 相似文献
56.
Grain growth during sintering of the polycrystalline high onset temperature superconductor YBa2Cu3O7−x has been examined by measuring grain sizes at various temperatures for different times above 900°C. The grain size distribution
is found to be predominately lognormal after some sintering time. The mean grain size increases with both temperature and
time. The standard deviation of the grain size distribution increases with temperature, but appears to be independent of time.
The grain growth law may have an exponent of five. The grain growth rate may be affected by the grain size of the calcined
powder. 相似文献
57.
S. K. Aggarwal 《International Journal of Pressure Vessels and Piping》1980,8(6):419-449
Finite element stress analyses are presented which allow for elastic and elasto-plastic material behaviour for axisymmetric problems of pressure vessels using isoparametric quadrilateral elements with linear, parabolic and cubic displacements. The traditional method of analysis and design of cylindrical pressure vessels with reversed dished ends is based on the well known British Standard BS 5500 Code.1 The stresses and displacements, especially at and near the junctions, are of great interest to designers. In view of the immense usefulness of such containers, a detailed post yield study has been made based on the stress-strain idealisation for isotropic strain hardening materials—H′= 0·0047E and Von Mises and Tresca yield criteria. The basis for the prediction of load increment sizes for the elasto-plastic analysis and the upper bound for collapse pressure are presented, as well as the excessive deformation and shakedown criteria suitable for the design of reversed dished end containers. 相似文献
58.
The problem of early failure modelling has been discussed comprehensively. Present models have been discussed and new models are suggested. A drawback of failure rate not being finite at t = 0 for some of the present models is eliminated in the suggested models. 相似文献
59.
The method evaluates the reliability of large computer communication systems by systematic decomposition of the probabilistic graph of the system into two parts using an appropriate cutset. A technique is evolved for determining the conditional success events using both the node removal and connection multiplication methods for path enumeration. An example is solved to show the versatility of the method. The results of the example are verified by using an existing algorithm. The suggested method is general and computationally economical. 相似文献
60.
A general and simple technique for the evaluation of symbolic reliability expression in the case of practical systems such as a communication system having fixed channel capacities of its various communicating links, a computer communication network allowing a fixed amount of data exchange amongst different terminals of various computer centres and a power distribution system having limited power ratings of its various power lines, is presented. A system is considered reliable only if it successfully transmits at least the required system capacity from the transmitter to the receiver station. In this method, the various branch sets are obtained which completely disrupt the communication path, i.e. ensure system failure. It is observed that these branch sets are not necessarily the cutsets in the usual graph theoretic sense. The unreliability expression is then determined by adopting an existing method for making various terms disjoint. Two typical examples are solved by this method. It is observed that the method is computationally fast and efficient. 相似文献