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排序方式: 共有1344条查询结果,搜索用时 15 毫秒
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An investigation of the through-thickness properties of carbon fibre prepreg laminates, Non-Crimp Fabric laminates and non-crimp 3D orthogonal woven composites by pull-through testing was performed. Influence of matrix system and curing temperature on the performance of the 3D woven composites was investigated. 相似文献
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Junying Liu Rui Zhang Itaru Osaka Sarada Mishra Anna E. Javier Detlef‐M. Smilgies Tomasz Kowalewski Richard D. McCullough 《Advanced functional materials》2009,19(21):3427-3434
New solution processable 4‐(2‐hexyldecan)‐4H‐bisthieno[2,3‐d:3′,2′‐b]pyrrole and 4,4′‐dialkyl‐2,2′‐bithiazole‐based copolymers (PBTzDTPs) are synthesized with excellent FET performance. These novel copolymers have considerable potential in printable electronics as they have high charge carrier mobilities, excellent air stability, good solution processibility, and no requirement for post‐deposition thermal annealing, all requirements for this field of application. The thin film transistors fabricated from PBTzDTPs achieve field effect mobilities as high as 0.14 cm2 V?1 s?1 with current on/off ratios up to 106 without thermal annealing. In addition, the devices exhibit stable performance in air, showing no significant degradation over 60 days. Moreover, the polymers described here provide an excellent example of the systems in which higher mobility performance does not require higher crystalline, long‐range ordered structures. Such a system appears to be particularly promising for rapid fabrication techniques, where kinetic conditions usually prevent the development of long‐range order. 相似文献
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Jan Bilski Monika Pinkas Dagmara Wojcik-Grzybek Marcin Magierowski Edyta Korbut Agnieszka Mazur-Bialy Gracjana Krzysiek-Maczka Slawomir Kwiecien Katarzyna Magierowska Tomasz Brzozowski 《International journal of molecular sciences》2022,23(7)
Both obesity and esophageal adenocarcinoma (EAC) rates have increased sharply in the United States and Western Europe in recent years. EAC is a classic example of obesity-related cancer where the risk of EAC increases with increasing body mass index. Pathologically altered visceral fat in obesity appears to play a key role in this process. Visceral obesity may promote EAC by directly affecting gastroesophageal reflux disease and Barrett’s esophagus (BE), as well as a less reflux-dependent effect, including the release of pro-inflammatory adipokines and insulin resistance. Deregulation of adipokine production, such as the shift to an increased amount of leptin relative to “protective” adiponectin, has been implicated in the pathogenesis of BE and EAC. This review discusses not only the epidemiology and pathophysiology of obesity in BE and EAC, but also molecular alterations at the level of mRNA and proteins associated with these esophageal pathologies and the potential role of adipokines and myokines in these disorders. Particular attention is given to discussing the possible crosstalk of adipokines and myokines during exercise. It is concluded that lifestyle interventions to increase regular physical activity could be helpful as a promising strategy for preventing the development of BE and EAC. 相似文献
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Branislaw Jariczuk Wieslaw Wojcik Tomasz Bialopiotrowicz 《Petroleum Science and Technology》1989,7(7):969-987
Contact angle measurements were carried out in coal / n-alkanes film - air bubble - water systems. Then theoretical an analysis of the equilibrium state of that system was carried out on the basis of the components of the surface free energy of coal of various ranks. The contact angles were measured for four ranks of Polish coal which surfaces were covered with n-alkanes film in the homological series from n-hexane to n-hexadecane. On the basis of the studies and calculations carried out we have concluded that the values of the contact angle depend on the rank of coal, a thickness of n-alkane film and its structure and the presence of water film under the air bubble. It was also found that the changes of the- values of the contact angles measured in the mentioned sytems as a function of the number of contacted air bubbles were similar to those calculated on the basis of the solution of Young equation in function of the surface free energy of coals precovered with n-alkane film. 相似文献
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Rheumatoid arthritis (RA) is the most commonly occurring chronic inflammatory arthritis, the exact mechanism of which is not fully understood. Tumor Necrosis Factor (TNF)-targeting drugs has been shown to exert high effectiveness for RA, which indicates the key importance of this cytokine in this disease. Nevertheless, the response to TNF inhibitors varies, and approximately one third of RA patients are non-responders, which is explained by the influence of genetic factors. Knowledge in the field of pharmacogenomics of anti-TNF drugs is growing, but has not been applied in the clinical practice so far. Different genome-wide association studies identified a few single nucleotide polymorphisms associated with anti-TNF treatment response, which largely map genes involved in T cell function. Studies of the gene expression profile of RA patients have also indicated specific gene signatures that may be useful to develop novel prognostic tools. In this article, we discuss the significance of TNF in RA and present the current knowledge in pharmacogenomics related to anti-TNF treatment response. 相似文献
38.
Tomasz Gancarz Katarzyna Berent Wojciech Skuza Katarzyna Janik 《Metallurgical and Materials Transactions A》2018,49(7):2684-2691
Magnesium has applications in the automotive and aerospace industries that can significantly contribute to greater fuel economy and environmental conservation. The Mg alloys used in the automotive industry could reduce mass by up to 70 pct, providing energy savings. However, alongside the advantages there are limitations and technological barriers to use Mg alloys. One of the advantages concerns phenomena occurring at the interface when joining materials investigated in this study, in regard to the effect of temperature and soldering time for pure Mg joints. Eutectic Zn-Al and Zn-Al alloys with 0.05 (wt pct) Li and 0.2 (wt pct) Na were used in the soldering process. The process was performed for 3, 5, and 8 minutes of contact, at temperatures of 425 °C, 450 °C, 475 °C, and 500 °C. Selected, solidified solder-substrate couples were cross-sectioned, and their interfacial microstructures were investigated by scanning electron microscopy. The experiment was designed to demonstrate the effect of time, temperature, and the addition of Li and Na on the kinetics of the dissolving Mg substrate. The addition of Li and Na to eutectic Zn-Al caused to improve mechanical properties. Higher temperatures led to reduced joint strength, which is caused by increased interfacial reaction. 相似文献
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DovidKotz TomaszLukasiak RickGentile 《世界电子元器件》2005,(6):44-46
在嵌入式应用中。随着“开源”C/C 代码越来越成为流行的用于替代基于版权算法的另一选择,挑战也随之而来。其中,最重要的问题是如何优化代码.使其在选定的处理器中更好地运行。本文将探讨开源算法在Blockfin处理器上的移植以及代码优化。 相似文献