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71.
72.
The vinyl acetate (VA) content in ethylene vinyl acetate (EVA) can significantly affect its performance as an encapsulant in photovoltaic modules under field conditions. EVA films of varying VA content (18, 24, 33, and 40%) have been prepared using twin screw extruder with the necessary additives and subsequently cured at 150 °C. All the EVA films have been subjected to UV radiation at a wavelength of 340 nm for 1000 and 2000 h to simulate accelerated field aging. The effects of accelerated aging on the gel content, mechanical properties, transmittance, Fourier transform infra-red (FTIR) spectra, thermal stability, degree of crystallinity, and yellowness have been studied. The observations made in this study of UV aging up to 2000 h suggests that the optimum range of VA content in EVA should be between 18 and 33% by weight. VA content beyond 40% degrades almost all properties needed for an encapsulate material after aging of only 2000 h. VA content of around 18% is the most stable under UV aging conditions but has a slightly lower value of transmittance for the unaged sample although the difference in transmittance between different specimens decreases with UV aging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48268. 相似文献
73.
In this research work, we have characterized and simulated a well-known hole transport material (HTM) for perovskite solar cell (PSC) and conductive polyme 相似文献
74.
Pancreatic ductal adenocarcinoma (PDAC), an extremely aggressive invasive cancer, is the fourth most common cause of cancer-related death in the United States. The higher mortality in PDAC is often attributed to the inability to detect it until it has reached advanced stages. The major challenge in tackling PDAC is due to its elusive pathology, minimal effectiveness, and resistance to existing therapeutics. The aggressiveness of PDAC is due to the capacity of tumor cells to alter their metabolism, utilize the diverse available fuel sources to adapt and grow in a hypoxic and harsh environment. Therapeutic resistance is due to the presence of thick stroma with poor angiogenesis, thus making drug delivery to tumor cells difficult. Investigating the metabolic mediators and enzymes involved in metabolic reprogramming may lead to the identification of novel therapeutic targets. The metabolic mediators of glucose, glutamine, lipids, nucleotides, amino acids and mitochondrial metabolism have emerged as novel therapeutic targets. Additionally, the role of autophagy, macropinocytosis, lysosomal transport, recycling, amino acid transport, lipid transport, and the role of reactive oxygen species has also been discussed. The role of various pro-inflammatory cytokines and immune cells in the pathogenesis of PDAC and the metabolites involved in the signaling pathways as therapeutic targets have been previously discussed. This review focuses on the therapeutic potential of metabolic mediators in PDAC along with stemness due to metabolic alterations and their therapeutic importance. 相似文献
75.
Seam strength prediction using loop strength has been found to be more accurate and has been consistently used by researchers over last few decades. But the testing gauge length for loop strength has not been standardized as in the case of thread tensile strength. In this paper, effect of gauge length on thread tensile strength and elongation in loop form and straight form has been studied. 40 tex and 60 tex mercerized cotton and spun polyester threads are used for the study. It is observed that there is no significant change in the loop strength of the threads as the gauge length increases, whereas the tensile strength of all threads decreases with the increase in gauge length. Elongation % is found to change significantly in both loop and straight form during tensile testing. Therefore, it is concluded that loop strength tests can be carried out at any gauge length unlike tensile testing of straight threads. 相似文献
76.
77.
Renu Agrawal 《Food Biotechnology》2013,27(3):227-246
Probiotics are among the important functional foods. They comprise approximately 65% of the world functional food market. Probiotic products are foods, which improve intestinal microflora and support good health of the consumer. The live bacteria present in the probiotic products are lactic acid bacteria, including Lactobacilli, Bifidobacteria and Enterococci. Apart from health claims and maintenance of intestinal microflora, they protect against infections, alleviate lactose intolerance, reduce blood cholesterol levels and also stimulate the immune system. The interactive research between physiology, microbiology, food technology and molecular biology followed by clinical trials may produce a multi-functional probiotic strain for human consumption. 相似文献
78.
Techniques to measure sorption and migration between small molecules and packaging. A critical review 下载免费PDF全文
Ashish A Kadam Thomas Karbowiak Andrée Voilley Frédéric Debeaufort 《Journal of the science of food and agriculture》2015,95(7):1395-1407
The mass transfer parameters diffusion and sorption in food and packaging or between them are the key parameters for assessing a food product's shelf‐life in reference to consumer safety. This has become of paramount importance owing to the legislations set by the regulated markets. The technical capabilities that can be exploited for analyzing product–package interactions have been growing rapidly. Different techniques categorized according to the state of the diffusant (gas or liquid) in contact with the packaging material are emphasized in this review. Depending on the diffusant and on the analytical question under review, the different ways to study sorption and/or migration are presented and compared. Some examples have been suggested to reach the best possible choice, consisting of a single technique or a combination of different approaches. © 2014 Society of Chemical Industry 相似文献
79.
80.
Effect of conventional and microwave sintering on the properties of yttria alumina garnet-dispersed austenitic stainless steel 总被引:3,自引:0,他引:3
S. S. Panda A. Upadhyaya D. Agrawal 《Metallurgical and Materials Transactions A》2006,37(7):2253-2264
The current study examines the effect of heating mode, temperature, and varying yttria alumina garnet (YAG) addition (5 and
10 wt pct) on the densification and properties of austenitic (316L) stainless steel. The straight 316L stainless steel and
316L-YAG composites were heated in a radiatively heated (conventional) and 2.45 GHz microwave sintering furnace. The compacts
were consolidated through solid state as well as supersolidus sintering at 1200 °C and 1400 °C, respectively. Both 316L and
316L-YAG compacts couple with microwaves and heat to the sintering temperature rapidly (∼45 °C/min). The overall processing
time was reduced by about 90 pct through microwave sintering. As compared to conventional sintering, compacts sintered in
microwaves exhibit higher densification and finer microstructure but no corresponding improvement in mechanical properties
and wear resistance. This has been correlated to elongated, irregular pore structure in microwave-sintered compacts. 相似文献