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1.
The Journal of Supercomputing - Spin-transfer torque random access memory (STT-RAM) is a suitable alternative to DRAM in the large last-level caches (L3Cs) on account of low leakage, the absence of... 相似文献
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The spray-freeze drying (SFD) technique was applied to sonicated aqueous suspensions of spray-dried montmorillonite clay (MMT) to produce highly porous agglomerates (SFD-MMT). Both MMT (used as a reference) and SFD-MMT were subsequently incorporated in polypropylene (PP) via melt compounding to produce 2 wt % nanocomposites with and without maleic anhydride grafted polypropylene (PP-g-MA). Polypropylene nanocomposites containing SFD-MMT exhibited thinner silicate flake layers compared to large agglomerates in PP/MMT nanocomposites. SFD-MMT particles became even more finer in the presence of PP-g-MA (i.e., in PP/PP-g-MA /SFD-MMT) where it hindered PP crystallization instead of serving as nucleation sites for the PP crystallization during rapid cooling. SFD-MMT improved the thermal stability of PP/PP-g-MA by 30°C compared to only 5–8°C for MMT/nanocomposites. MMT acts as a heterogeneous nucleating agent in the nucleation-controlled PP nanocomposites, but the hindrance effect was observed for the PP/PP-g-MA with SFD-MMT. PP/PP-g-MA/SFD-MMT exhibited twice the edge surface energy as compared to PP/PP-g-MA/MMT. The incorporation of both types of MMT raised the tensile moduli of PP and PP/PP-g-MA, with no improvement in their tensile strength and a decrease in the elongation at break. The PP/PP-g-MA/SFD-MMT showed brittle failure. POLYM. ENG. SCI., 60:168–179, 2020. © 2019 Society of Plastics Engineers 相似文献
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Ankit Sachan Shyam Kamal Sorin Olaru Devender Singh Xiaogang Xiong 《国际强度与非线性控制杂志
》2020,30(6):2443-2460
》2020,30(6):2443-2460
This article presents a hands‐off control design for discrete‐time nonlinear system with a special type of nonlinear sector termed as “discrete‐time sector.” The design method to define the boundary of a discrete‐time sector is done with control‐Lyapunov function. The generalization of nonlinear system is viewed in the perspective of a comparison function. By means of a proposed sector, a switching control is designed such that no control action is experienced inside the sector thus, saving unnecessary control efforts. However, to study the robustness for discrete‐time system, a hands‐off control is modified to ensure the monotonic decrease in the energy of the system. Finally, the proposed approach is verified with the simulation results. 相似文献
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Brandon Tonnis Ming Li Wang Xianran Li Jianping Wang Naveen Puppala Shyam Tallury Jianming Yu 《Journal of the American Oil Chemists' Society》2020,97(9):1001-1010
The level of oleic acid is an important parameter in determining seed nutritional quality and oil stability. The level of oleic acid in peanut is genetically controlled by a pair of fatty acid desaturase genes (FAD2A and FAD2B), but the environmental conditions of the production sites can also have a significant effect. To investigate the effect of gene and environment interaction, 45 accessions were grown at three locations for 2 years. Environmental data were collected; individual plants were genotyped with functional SNP markers from FAD2A and FAD2B; and seed level of oleic acid was determined by gas chromatography. Three FAD2A/FAD2B genotypes (448G/no insertion 442A, 448A/no insertion 442A, and 448A/insertion 442A) were identified and designated as G/W, A/W, and A/A, respectively. A/A genotype averaged the highest level of oleic acid (80.0%), followed by A/W (56.0%), and then G/W (40.7%). Analysis of gene and environment interaction revealed that oleic acid phenotype plasticity could be explained by the interaction of FAD2 genotype and photothermal time, which quantified environmental conditions. The A/W genotype was the most sensitive to photothermal time changes. The oleic acid plasticity revealed in this study would be useful for breeders, farmers, and product processors. 相似文献
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Astrid Ahlinder Tiziana Fuoco Álvaro Morales-López Mohammed A. Yassin Kamal Mustafa Anna Finne-Wistrand 《应用聚合物科学杂志》2020,137(15):48550
Although additive manufacturing through melt extrusion has become increasingly popular as a route to design scaffolds with complex geometries the technique if often limited by the reduction in molecular weight and the viscoelastic response when degradable aliphatic polyesters of high molecular weight are used. Here we use a melt extruder and fused filament fabrication printer to produce a reliable nondegradative route for scaffold fabrication of medical grade copolymers of L-lactide, poly(ε-caprolactone-co-L-lactide), and poly(L-lactide-co-trimethylene carbonate). We show that degradation is avoided using filament extrusion and fused filament fabrication if the process parameters are deliberately chosen based upon the rheological behavior, mechanical properties, and polymer composition. Structural, mechanical, and thermal properties were assessed throughout the process to obtain comprehension of the relationship between the rheological properties and the behavior of the medical grade copolymers in the extruder and printer. Scaffolds with a controlled architecture were achieved using high-molecular-weight polyesters exhibiting a large range in the elastic response causing negligible degradation of the polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48550. 相似文献
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M. Kamal Warshi Vikash Mishra Vinayak Mishra Rajesh Kumar P.R. Sagdeo 《Ceramics International》2018,44(12):13507-13512
Rare-earth orthoferrites (RFeO3) are well-known for the antiferromagnetic ground state. However, some of the recent experimental results suggest that the few members of RFeO3 family possess ferromagnetism. In the present investigation we report the possible origin of ferromagnetism in antiferromagnetic YFeO3 using density functional theory. For this purpose, we have considered pure as well as self-doping in YFeO3 i.e. by considering the point defect at Y, Fe and O sites. Our finding suggests that the point defects in YFeO3 results in the mixed-valence state of Fe, which may result in ferromagnetism through Zener double exchange mechanism. 相似文献
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In this paper, we consider the classical finite mixture model, which is an effective tool for modeling lifetime distributions for random samples from heterogeneous populations. We discuss new results on stochastic comparison for two finite mixtures when each of them is drawn from one of the following semiparametric families, i.e., proportional hazards, accelerated lifetime and proportional reversed hazards. 相似文献