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重点介绍了工厂现有设备条件和技术力量比较薄弱的情况下。通过消化吸收从瑞士ABB公司引进的技术、进行认真的技术准备和开展技术攻关,完成首台60MW空内冷汽轮发电机考核样机试制的主要经验。  相似文献   
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In this paper, we have developed a new full-adder cell using multiplexing control input techniques (MCIT) for the sum operation and the Shannon-based technique to implement the carry. The proposed adder cell is applied to the design of several 8-bit array multipliers, namely a Braun array multiplier, a CSA multiplier, and Baugh–Wooley multipliers. The multiplier circuits are designed using DSCH2 VLSI CAD tools and their layouts are generated by Microwind 3 VLSI CAD tools. The output parameters such as propagation delay, total chip area, and power dissipation are calculated from the simulated results. We have also calculated energy per instruction (EPI), throughput, latency, signal-to-noise ratio (SNR), and the effect of temperature on the drain current by using the generated layout output parameter of a BSIM 4 advanced analyzer. The simulated results of the proposed adder-based multiplier circuit are compared with a cell multiplier that utilizes a MCIT-based adder, a cell multiplier composed of complementary pass transistor logic-based (CPL) adders and those of other published multipliers circuits. From the analysis of these simulated results, it was found that the proposed multiplier circuit gives better performance in terms of power, propagation delay, latency and throughput than other published results.  相似文献   
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Objective: The present study tested the hypothesis that social problem solving (SPS) served to mediate the relationship between preceived stress and noncardiac chest pain (NCCP). Design: Adults undergoing stress myocardial perfusion imaging (MPI) to determine the presence of underlying cardiovascular disease related to the experience of chest pain were recruited prior to stress testing to complete a series of self-report inventories. Main Outcome Measures: MPI results were used to identify individuals with NCCP (N = 166; 91 men, 75 women; mean age = 53.92 years, SD = 11.98). Measures included perceived stress, SPS, and chest pain frequency and intensity. Results: In direct tests of the mediational effects of SPS, it was found that two problem-solving dimensions, negative problem orientation and rational problem solving, each served as significant mediators of the effects of stress on both NCCP intensity and frequency. Conclusion: These results support a mediational analysis of NCCP that includes stress and SPS. As such, it identifies SPS as a potentially important clinical target to consider when developing future psychosocial-based therapy protocols for treating individuals with NCCP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Garden cress (Lepidium sativum L.) is an edible, underutilised herb, grown mainly for its seeds in India. Physicochemical properties, minor components (unsaponifiable matter, tocopherols, carotenoids), fatty acid composition and storage stability of garden cress seed oil (GCO) were studied. Cold press, solvent and supercritical CO2 extraction methods were employed to extract the oil. The total oil content of garden cress (GC) seeds was 21.54, 18.15 and 12.60% respectively by solvent, supercritical CO2 and cold press methods. The physical properties of GCO extracted by the above methods were similar in terms of refractive index, specific gravity and viscosity. However, cold pressed oil showed low PV and FFA compared to the oil extracted by other methods. α-Linolenic acid (34%) was the major fatty acid in GCO followed by oleic (22%), linoleic (11.8%), eicosanoic (12%), palmitic (10.1%) erucic (4.4%), arachidic (3.4%) and stearic acids (2.9%). Oleic acid (39.9%) and α-linolenic acid (42.1%) were the predominant fatty acids at the sn-2 position. The total tocopherol and carotenoid content of GCO was 327.42 and 1.0 μmol/100 g oil, respectively. The oil was stable up to 4 months at 4 °C. Tocopherol and BHT offered the least protection, while ascorbyl palmitate (200 ppm) offered the maximum protection to the oil, when subjected to the accelerated oxidative stability test. Thus GCO can be considered as a fairly stable oil with a high content of α-linolenic acid.  相似文献   
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Two novel bioisosteres of cabozantinib, 3 and 4, were designed and synthesized. The benzene ring in the center of the cabozantinib structure was replaced by trimethylpyridine (3) and pyridine (4), respectively. Surprisingly, the two compounds showed extremely contrasting mesenchymal–epithelial transition factor (c-Met) inhibitory activities at 1 μM concentration (4% inhibition of 3 vs. 94% inhibition of 4). The IC50 value of compound 4 was 4.9 nM, similar to that of cabozantinib (5.4 nM). A ligand-based docking study suggested that 4 includes the preferred conformation for the binding to c-Met in the conformational ensemble, but 3 does not. The anti-proliferative activity of compound 4 against hepatocellular carcinoma (Hep3B and Huh7) and non-small-cell lung cancer (A549 and H1299) cell lines was better than that of cabozantinib, whereas 3 did not show a significant anti-proliferative activity. Moreover, the tumor selectivity of compound 4 toward hepatocellular carcinoma cell lines was higher than that of cabozantinib. In the xenograft chick tumor model, compound 4 inhibited Hep3B tumor growth to a much greater extent than cabozantinib. The present study suggests that compound 4 may be a good therapeutic candidate against hepatocellular carcinoma.  相似文献   
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Media access protocols in wireless networks require each contending node to wait for a backoff time, chosen randomly from a fixed range, before attempting to transmit on a shared channel. However, nodes acting in their own selfish interest may not follow the protocol. In this paper, a static version of the problem is modeled as a strategic game played by non-cooperating, rational players (the nodes). The objective is to design a game which exhibits a unique, a priori mixed-strategy Nash equilibrium. In the context of the media access problem, the equilibrium of the game would correspond to nodes choosing backoff times randomly from a given range of values, according to the given distribution. We consider natural variations of the problems concerning the number of actions available to the players and show that it is possible to design such a game when there are at least two players that each have the largest number of possible actions among all players. In contrast, we show that if there are exactly two players with different number of actions available to them, then it becomes impossible to design a strategic game with a unique such Nash equilibrium.  相似文献   
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水-甲醇混合工质振荡热管温度振荡及传热特性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
通过实验研究了水-甲醇混合工质振荡热管充液率分别为55%、62%、70%、90%下,体积比分别为13∶1、4∶1、1∶1、1∶4、1∶13时的温度振荡以及热阻特性,并与水、甲醇纯工质振荡热管进行了对比。研究表明,混合工质振荡热管的振幅较纯工质大且较为均匀;较大充液率时(62%及以上),大多数混合工质振荡热管热阻大于两种纯工质;中等充液率时,部分振荡热管出现烧干现象,受黏度影响,大多数混合工质振荡热管出现烧干现象时的功率较小,热阻较纯工质大。但是,在水中加入少量甲醇(13:1)做工质的振荡热管在充液率为55%下不易发生烧干,且热阻较其他工质低。振荡热管的热阻特性受工质黏度、气液相平衡等因素的共同作用,在不同工况下,各因素作用效果不同。  相似文献   
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