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21.
胡举凡 《科技信息》2013,(21):454-454,456
本文介绍了舞钢公司动力厂四号总降TCR控制系统。它通过控制调节串联在电抗器回路中晶闸管的导通角的大小,来控制电路中感性负载大小,从而起到改善电路中功率因数的作用,保证了公司电网的质量。  相似文献   
22.
La0.8Sr0.2MnO3 films were prepared on SrTiO3 (STO) and LaAlO3 (LAO) substrates using excimer laser-assisted metal organic deposition (ELAMOD). For the LAO substrate, no epitaxial La0.8Sr0.2MnO3 film was obtained by laser irradiation in the fluence range from 60 to 110 mJ/cm2 with heating at 500 °C. On the other hand, an epitaxial La0.8Sr0.2MnO3 film on the STO substrate was formed by laser irradiation in the fluence range from 60 to 100 mJ/cm2 with heating at 500 °C. To optimize the electrical properties for an IR sensor, the effects of the laser fluence, the irradiation time and the film thickness on the temperature dependence of the resistance and temperature coefficient of resistance (TCR: defined as 1/R·(dR/dT)) of the LSMO films were investigated. An LSMO film on the STO substrate that showed the maximum TCR of 3.9% at 265 K was obtained by the ELAMOD process using the KrF laser.  相似文献   
23.
The thymus hosts the development of a specific type of adaptive immune cells called T cells. T cells orchestrate the adaptive immune response through recognition of antigen by the highly variable T-cell receptor (TCR). T-cell development is a tightly coordinated process comprising lineage commitment, somatic recombination of Tcr gene loci and selection for functional, but non-self-reactive TCRs, all interspersed with massive proliferation and cell death. Thus, the thymus produces a pool of T cells throughout life capable of responding to virtually any exogenous attack while preserving the body through self-tolerance. The thymus has been of considerable interest to both immunologists and theoretical biologists due to its multi-scale quantitative properties, bridging molecular binding, population dynamics and polyclonal repertoire specificity. Here, we review experimental strategies aimed at revealing quantitative and dynamic properties of T-cell development and how they have been implemented in mathematical modeling strategies that were reported to help understand the flexible dynamics of the highly dividing and dying thymic cell populations. Furthermore, we summarize the current challenges to estimating in vivo cellular dynamics and to reaching a next-generation multi-scale picture of T-cell development.  相似文献   
24.
Voltage responsivity of bolometer will benefit from high temperature coefficient of resistance (TCR) of the material. The Nb5N6 thin solid films we proposed in this paper have high TCR, compared with the commonly-used materials such as Nb and Bi. The films were sputtered on Si(100), SiO2/Si(100), SiO2 substrates by using radio frequency (rt) magnetron sputtering. The deposition conditions have been optimized to get high TCR. The highest TCR is over 0.91% K^-1 at 300 K and up to 4.5% K^-1 -7% K^-1 at 78 K, which is good enough to be used in terahertz detection and thermometer fabrication in the range from 78 K to 300 K.  相似文献   
25.
Thin amorphous tantalum films are prepared on Si(111) substrates in a metallic glassy state. The amorphous monoatomic state of the film is characterized by X‐ray diffraction studies. The glassy state leads to a negative t emperature c oefficient of the r esistivity (TCR) for low sample temperatures <200 K which is attributed to incipient localization. Above 200 K a positive TCR is observed as expected for a normal Boltzmann transport regime. Upon heating the Si substrate to 1200 K TaSi2 is formed out of the amorphous tantalum film and the silicon substrate. The TaSi2 layer is crystalline as evident from X‐ray diffraction data.

  相似文献   

26.
将T细胞受体(TCR)的活性与免疫酪氨酸受体激活基序(ITAM)活性联系起来,深入考虑了TCR与其配体的亲和力和离解率.结果表明抗原多肽上信号氨基酸部分的细小差别,将有效地引起截然不同的T细胞应答反应.发生在T细胞应答早期信号事件中的TCR与其配体的亲和力和离解率参与决定了最终的T细胞应答结果.  相似文献   
27.
TCR型SVC与电力系统配套,可以实现无功补偿,稳定系统电压、治理闪变,谐波等来改善电网质量。本文叙述了SVC技术的意义、作用、分类,详细地分析了的系统组成和补偿原理。  相似文献   
28.
This paper reports a novel technique for fabrication of a flexible skin with a temperature sensor array (40&#215;1 sensors). A simplified MEMS technology using platinum resistors as sensing materials, which are sandwiched between two polyimide layers as flexible substrates is developed. The two polyimide layers are deposited on top of a thin aluminum layer, which serves as a sacrificial layer such that the flexible skin can be released by metal etching and peeled off easily. The flexible skin with a temperature sensor array has a high mechanical flexibility and can be handily attached on a highly curved surface to detect tiny temperature distribution inside a small area. The sensor array shows a linear output and has a sensitivity of 7.5mV/℃ (prior to amplifiers) at a drive current of 1 mA. To demonstrate its applications, two examples have been demonstrated, including measurement of temperature distribution around a micro heater of a micro PCR (polymerase chain reaction) chip for DNA amplification and detection of separation point for flow over a circular cylinder. The development of the flexible skin with a temperature sensor array may be crucial for measuring temperature distribution on any curved surface in the fields of aerodynamics, space exploration, auto making and biomedical applications etc.  相似文献   
29.
为了研究蛋白质二硫键异构酶A3前体(protein disulfide isomerase A3 precursor, PDIA3)在T细胞受体(T cell receptor, TCR)信号通路中的具体功能,利用电穿孔法将T 细胞内的PDIA3蛋白水平敲低,通过Western blotting检测ζ-链相关蛋白70(zeta-chain associated protein 70, ZAP70)的磷酸化修饰水平, 酶联免疫吸附测定(enzyme linked immunosorbent assay, ELISA)实验检测细胞因子IL-2的分泌情况,流式细胞术分析分化抗原簇69(cluster of differentiation 69, CD69)表达水平及荧光素酶报告基因检测NF-κB信号通路.结果显示:T细胞中PDIA3蛋白下调后导致ZAP70蛋白的磷酸化水平、CD69表达和IL-2的分泌都明显降低,并且影响了NF-κB信号通路,表明PDIA3蛋白对T细胞的活化有促进作用,参与T细胞TCR信号通路的调控,为进一步深入研究PDIA3与TCR下游一些功能蛋白的相互作用打下了基础.  相似文献   
30.
《Arabian Journal of Chemistry》2020,13(12):8965-8978
Present study was intendant to assess heavy metals (HMs) concentration and associated health risk in processed fruits’ products sold in the local markets of North Pakistan. In total seven metals viz. cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb) and zinc (Zn) were quantified in 345 samples of different brands categorized into eight groups (Sauces, Ketchup, Juices, Jams, canned fruits, tomato paste, marmalades and pickles). On the comparative basis, Fe was dominating with highest concentration in pickles, canned fruits and sauces at 143.3 ± 43.2, 83.64 ± 23.19 and 50.17 ± 15.1 mg/kg, respectively), followed by Cd in sauces (22.94 ± 6.91 mg/kg), Cr in juices (12.97 ± 3.91 mg/kg) and Pb in pickles (12.53 ± 3.77 mg/kg). Measured levels of these metals varied significantly and were relatively higher than their permissible limits. Univariate and multivariate analysis depicted strong association among Cr, Co, Pb and Fe and confirmed HMs contamination through natural and anthropogenic sources in processed foods. Health risk index (HRI) for Cd, Cr and Pb was greater than unity (<1.0), particularly in sauces, jams and canned fruits. Target hazard quotient (THQ) and hazard index (HI) of Cd, Cr and Pb were relatively high. But target cancer risk (TCR) assessment indicates that these metals were within the acceptable limit, except for Cd concentration in sauces, jams and canned fruits that may cause cancer to consumers.  相似文献   
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