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91.
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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93.
Miguel García Luis Marroyo Eduardo Lorenzo Javier Marcos Miguel Prez 《Progress in Photovoltaics: Research and Applications》2015,23(10):1381-1389
When evaluating the performance of a photovoltaic (PV) system, it is extremely important to correctly measure the plant operating conditions: incident irradiation and cell temperature. At large‐size PV plants, the possible dispersion of the plant operating conditions may affect the representativeness of the values measured at one single point. The available literature contains many observations on irradiance dispersion (typically associated to high temporal resolution experiments) and its effects on the PV power output (unexpected power transients, power fluctuations, etc.). However no studies have been made on the long‐term energy‐related effects of geographic dispersion of solar irradiation, which could affect, for example, to the uncertainty in determining energy performance indexes like PR. This paper analyses the geographical dispersion in the PV operating conditions observed at low temporal resolutions (day, month and year) at two PV plants located, respectively, in the south of Portugal and the north of Spain. It shows that daily irradiation deviations are significantly higher than is commonly supposed. Furthermore, once the measurement points are a certain distance apart (a few hundred metres), the deviations in irradiation appear to be independent of distance. This could help to determine how many irradiance sensors to install in order to reduce uncertainty. Daily mean temperature differences between different points at a large‐scale PV plant range from 1 to 7 K and are not related to the distance between measurement points. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
94.
Javier Gonzalez 《国际射频与微波计算机辅助工程杂志》1996,6(2):107-114
The design and performance of a wide band active GaAs IC 180° differential phase shifter are presented. A two-stage GaAs IC was developed containing a microwave differential amplifier and a matched common-gate input. The active phase shifter achieved a 10° phase unbalance and an isolation at the output ports of better than 10 dB in the 1-10-GHz band. A large percentage of the GaAs chip contains active devices thereby providing a very large operating bandwidth and a reduced surface area. This active phase shifter presents an interesting alternative to the passive rat-race or an equivalent coupler for radio mobile communications. © 1996 John Wiley & Sons, Inc. 相似文献
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97.
Maria A. Ortiz F. Javier Piedrafita Adel Nefzi 《International journal of molecular sciences》2022,23(8)
A growing body of evidence suggests a pathogenic role for pro-inflammatory T helper 17 cells (Th17) in several autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease, type I diabetes, and psoriasis—diseases for which no curative treatment is currently available. The nuclear retinoic acid receptor–related orphan receptors alpha and gamma (RORα/γ), in particular the truncated isoform RORγt that is specifically expressed in the thymus, play a critical role in the activation of a pro-inflammatory Th17 response, and RORγ inverse agonists have shown promise as negative regulators of Th17 for the treatment of autoimmune diseases. Our study underscores the screening of a large combinatorial library of 1,5-disubstituted acylated 2-amino-4,5-dihydroimidazoles using a demonstrated synthetic and screening approach and the utility of the positional scanning libraries strategy for the rapid identification of a novel class of ROR inhibitors. We identified compound 1295-273 with the highest activity against RORγ (3.3 µM IC50) in this series, and almost a two-fold selectivity towards this receptor isoform, with 5.3 and 5.8 µM IC50 against RORα and RORβ cells, respectively. 相似文献
98.
Helena M. Moreno José Carballo A. Javier Borderías 《Innovative Food Science and Emerging Technologies》2010,11(2):394-400
Changes in physicochemical properties of raw-appearing restructured models made from hake (Merluccius capensis) muscle, using cold gelation technology by addition of sodium alginate and microbial transglutaminase (MTGase), were studied during frozen storage at ? 15 °C.Among the more interesting results, addition of MTGase produced more protein aggregation in models processed by muscle homogenization and thus the protein network that formed in the gel was better than in samples with added sodium alginate. All samples presented enhanced changes in mechanical properties such as gel strength in the course of frozen storage. The protein network that formed was better organized as shown by the ultrastructure analysis and by protein aggregation data from the beginning of storage, and as a result Water Binding Capacity was greater in restructured models processed by muscle homogenization. Some of the models studied presented lipid oxidation during frozen storage, slightly more in the ones with MTGase added.Industrial RelevanceThe industrial relevance of the present work is to establish bases for using fish fillet trimmings and minced muscle to prepare restructured products that can be commercialized in a raw state and that could also support frozen storage in order to prolong the self-life in the market. The models studied here are not final products but the base with which to prepare them. One possibility of them is to process this kind of products with technologies normally used in whole fish muscle such as smoked fish fillets, carpaccios or marinated products. In addition, these raw restructured products can be commercialized to be cooked as a normal fresh fish fillet or pieces of fillet in a variety of preparations, and also products that contain a high amount of salt. Samples elaborated by binding larger muscle fragments imitate well the original fibrousness of the muscle so that it could be used to elaborate products similar to hamburgers or others that will be fried in batter. 相似文献
99.
Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a serious, costly, and persistent health problem with an estimated prevalence in Western countries around 0.5% of the general population; its socioeconomic impact is comparable with that for chronic diseases such as diabetes. Conventional treatment involves escalating drug regimens with concomitant side effects followed, in some cases, by surgical interventions, which are often multiple, mainly in Crohn's disease. The goal of finding a targeted gut‐specific immunotherapy for IBD patients is therefore an important unmet need. However, to achieve this goal we first must understand how dendritic cells (DC), the most potent antigen present cells of the immune system, control the immune tolerance in the gastrointestinal tract and how their properties are altered in those patients suffering from IBD. In this review, we summarize the current available information regarding human intestinal DC subsets composition, phenotype, and function in the human gastrointestinal tract describing how, in the IBD mucosa, DC display pro‐inflammatory properties, which drive disease progression. A better understanding of the mechanisms inducing DC abnormal profile in IBD may provide us with novel tools to perform tissue specific immunomodulation. 相似文献
100.
Estimation of freezing storage time and quality changes in hake (Merluccius merluccius, L.) by low field NMR 总被引:4,自引:0,他引:4
The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (Merluccius merluccius) frozen stored at -10°C for up to 6months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T(2b)), trapped water (T(21)) and free water (T(22)). As storage time increased, and concomitant with an increase in the T(22) and a decrease in the T(21) water populations, the water holding capacity (WHC) and apparent viscosity values decreased and the shear strength increased, reflecting the characteristic loss of juiciness and tougher texture developed by hake during frozen storage. Two mathematical models were constructed: a simple regression using the biexponential analysis of the relaxation times (T(21), T(22)) and amplitudes (A(21), A(22)) and a partial least square regression (PLS) of CONTIN analysis. Both models seemed suitable to estimate the quality of the product. 相似文献