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1.
Mit Rita Goswami Prayas Singh Pankaj Chamoli Sumit Bhardwaj Kuldeep Kumar Raina Ravi Kumar Shukla 《应用聚合物科学杂志》2021,138(43):51260
ZnO rice like nonarchitects are grafted on the graphene carbon core via a rapid microwave synthesis route. The prepared grafted systems are characterized via XRD, SEM, RAMAN, and XPS to examined the structural and morphological parameters. Zinc oxide grafted graphene sheets (ZnO-G) are further doped in β-phase of polyvinylidene fluoride (PVDF) to prepare the polymer nanocomposites (PNCs) via mixed solvent approach (THF/DMF). β-phase confirmation of PVDF PNCs is done by FTIR studies. It is observed that ZnO-G filler enhances the β-phase content in the PNCs. Non-doped PVDF and PNCs are further studied for rheological behavior under the shear rate of 1–100 s−1. Doping of ZnO-G dopant to the PVDF matrix changes its discontinuous shear thickening (DST) behavior to continues shear thickening behavior (CST). Hydrocluster formation and their interaction with the dopant could be the reason for this striking DST to CST behavioral change. Strain amplitude sweep (10−3% -10%) oscillatory test reveals that the PNCs shows extended linear viscoelastic region with high elastic modulus and lower viscous modulus. Effective shear thickening behavior and strong elastic strength of these PNCs present their candidature for various fields including mechanical and soft body armor applications. 相似文献
2.
Multimedia Tools and Applications - In the way of communication, facial expression act as non-verbal communication and play an important role in social interaction by providing some contextual... 相似文献
3.
Tensile testing of a modified 9Cr–1Mo steel in two microstructural conditions (710T– normalized at 1100°C, tempered at 710°C, and 550T – normalized at 1100°C tempered at 550°C) in the temperature range 25–450°C, under strain rates of 2.3×10-5–2.3×10-3s-1, exhibited serrated flow curves, with serrations appearing almost at the onset of deformation and disappearing before ultimate strengths were attained. The serrated flow curves (characteristics of dynamic strain ageing) were accompanied by increased ultimate strengths, loss of ductility and negative strain-rate sensitivity, relative to the ambient temperature properties. However, the increase in ultimate strength and the reduction in ductility were much larger for 710T specimens, as compared to 550T ones. In the dynamic strain ageing regime, the work-hardenability of 710T specimens increased rapidly while that of 550T specimens remained practically unaffected. Based on the microstructural consideration and the observed activation energy of 45 kJ mol-1, it is proposed that serrations are initiated by a nitrogen atmosphere formation on the waiting dislocations by a pipe diffusion mechanism, and they disappear by diffusion to the precipitate sinks during deformation. Because the fine alloy carbide precipitates in 550T specimens are more effective sinks than those of 710T ones, they can cause much faster depletion of the atmosphere, resulting in a much smaller effect of dynamic strain ageing on the tensile properties of 550T specimens. 相似文献
4.
SHELF-LIFE MODELING OF SWEETENED CONDENSED MILK BASED ON KINETICS OF MAILLARD BROWNING 总被引:1,自引:0,他引:1
A. A. PATEL H. GANDHI SUDHIR SINGH G. R. PATIL 《Journal of Food Processing and Preservation》1996,20(6):431-451
Nonenzymatic browning and related changes were monitored in commercial sweetened condensed milk stored at 7, 15, 30, 45 and 55C. Darkening of the color measured in terms of absorbance (100 - reflectance percent) followed zero-order kinetics, the apparent activation energy (Ea ) being 45.2 kJ/mol at 7–30C and 139.9 kJ/mol at > 30–55C. Hydroxy-methyl-furfural (HMF) showed a first-order increase, the associated Ea values being smaller than those for absorbance. The pH exhibited a linear decline after a small initial rise at 30C and below. As browning progressed, the coffee whitening ability of the product decreased along zero-order kinetics. The Q10 values for these variables ranged from 1.21 to 1.84 for temperatures up to 30C and were nearly 2–3 times higher above 30C. The sensory color score was negatively correlated with absorbance. The linear regression of color score on absorbance and the temperature dependence of the latter as expressed by Arrhenius relationship were combined into a mathematical model which could be useful in predicting the product's shelf-life. 相似文献
5.
Samuel L. Manzello Richard G. Gann Scott R. Kukuck Kuldeep Prasad Walter W. Jones 《火与材料》2007,31(5):297-310
A gypsum wall assembly was exposed to an intense real‐scale compartment fire. For the wall assembly, temperatures were measured at the exposed face, within the stud cavity, and at the unexposed face during the fire exposure. Total heat flux gauges were used to measure the temporal variation of the energy incident on the walls, and cameras, both visual and infrared, were used to image the unexposed face of the wall assembly during the fire exposure. The behaviour of the wall assembly under the fire load is discussed as are current model results for a simulation of the fire test. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
6.
SIMULATION OF THAWING OF FOODS USING FINITE ELEMENT METHOD 总被引:2,自引:0,他引:2
7.
YOUSSEF S. HAFEZ ALI I. MOHAMED GURBAX SINGH FAWZY M. HEWEDY 《Journal of food science》1985,50(5):1271-1274
Two hundred grams of soybean seeds (moisture contents of 7.4, 15.3, 22.5, and 30.5%) were irradiated at dose levels of 0, 1, 5, 10, 20, 40, 60, 80 and 100 KGy using Cobalt-60 source. Radiation dose of 100 KGy caused a decrease in the percentage of nitrogen solubility from 80.3 to 67.2, 80.3 to 57.8, and 68.1 to 48.8 when deionized H2O, 0.6M NaCl, and 0.2M Cacl2 were used as solvents, respectively. Inhibition of 71% of lipoxygenase activities, 25.4% trypsin inhibitor activities, and 16.7% chymotrypsin inhibitor activities were found when the soybean seeds were irradiated at 100 KGy. 相似文献
8.
Experimental residence-time distribution (RTD) characteristics of an extrusion process may be used to estimate the extent of mixing experienced in the extruder. Using earlier theories of laminar mixing and striation thickness reduction, a new approach to estimate efficacy of mixing of two phases in the mixing zone of the extruder is proposed. Predicting the time required to achieve complete mixing and comparing it with the minimum time (plug flow time) that the extrudate spends in the mixing zone gives a ratio that can be used to evaluate the adequacy of extruder operating conditions for good mixing of gas/fluid injection and extrudate. Twin-screw extrusion of cornmeal with carbon dioxide injection were used to investigate the effect of CO2 injection pressure and extruder screw speeds on mixing. Lower CO2 injection pressures (25 bars) and lower screw speeds (150 rpm) were theoretically shown to enhance mixing. Scanning electron micrographs (SEMs) of experimental samples taken showed smaller and more uniform cell structures for those conditions which were predicted to favor better mixing. 相似文献
9.
Pushpinder SINGH 《Frontiers of Computer Science in China》2014,(5):741-752
In this paper, we propose some distance measures between type-2 fuzzy sets, and also a new family of utmost distance measures are presented. Several properties of differ- ent proposed distance measures have been introduced. Also, we have introduced a new ranking method for the ordering of type-2 fuzzy sets based on the proposed distance measure. The proposed ranking method satisfies the reasonable prop- erties for the ordering of fuzzy quantities. Some properties such as robustness, order relation have been presented. Lim- itations of existing ranking methods have been studied. Fur- ther for practical use, a new method for selecting the best alternative, for group decision making problems is proposed. This method is illustrated with a numerical example. 相似文献
10.
Kuldeep Chouhan Mukesh Yadav Ranjeet Kumar Rout Kshira Sagar Sahoo NZ Jhanjhi Mehedi Masud Sultan Aljahdali 《计算机系统科学与工程》2023,45(2):1113-1128
Twitter is a radiant platform with a quick and effective technique to analyze users’ perceptions of activities on social media. Many researchers and industry experts show their attention to Twitter sentiment analysis to recognize the stakeholder group. The sentiment analysis needs an advanced level of approaches including adoption to encompass data sentiment analysis and various machine learning tools. An assessment of sentiment analysis in multiple fields that affect their elevations among the people in real-time by using Naive Bayes and Support Vector Machine (SVM). This paper focused on analysing the distinguished sentiment techniques in tweets behaviour datasets for various spheres such as healthcare, behaviour estimation, etc. In addition, the results in this work explore and validate the statistical machine learning classifiers that provide the accuracy percentages attained in terms of positive, negative and neutral tweets. In this work, we obligated Twitter Application Programming Interface (API) account and programmed in python for sentiment analysis approach for the computational measure of user’s perceptions that extract a massive number of tweets and provide market value to the Twitter account proprietor. To distinguish the results in terms of the performance evaluation, an error analysis investigates the features of various stakeholders comprising social media analytics researchers, Natural Language Processing (NLP) developers, engineering managers and experts involved to have a decision-making approach. 相似文献