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941.
多线程同步技术在电感自动测试系统中的应用   总被引:1,自引:0,他引:1  
多线程同步技术能够更好地开发并行性任务和提高系统性能.为实现高速的仪器测量与低速的机械动作之间的有机协调,提高工作的效率,在研究了Windows线程同步机制和CVI多线程技术中数据保护的基础上,给出了利用事件内核对象和线程安全变量来实现电感自动测试系统的方法,同时给出了工作线程的流程图.实际使用结果表明:该系统对单台测...  相似文献   
942.
The work studies a micro humidity sensor integrated with a seven-stage ring oscillator circuit-on-a-chip fabricated by the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process and a post-process. The structure of the humidity sensor consists of interdigitated electrodes and a sensing film. The sensing film is cobalt oxide nanosheet that is prepared by a precipitation-oxidation method. The sensor, which is a capacitive type, changes in capacitance when the sensing film adsorbs or desorbs water vapor. The ring oscillator circuit is employed to convert the capacitance of the sensor into the oscillation frequency output. The post-process of the sensor includes etching the sacrificial oxide layer and coating the sensing film on the interdigitated electrodes.  相似文献   
943.
Pd-catalysed decarboxylative Suzuki reactions and orthogonal Cu-based O-arylation reactions of aromatic carboxylic acids are reported. The new reactions may provide alternative routes for the synthesis of some biaryls and aromatic carboxylic esters.  相似文献   
944.
A tandem NHC-catalyzed aza-benzoin/Michael reaction has been developed as a method to efficiently produce dihydroindenones and pyrrolidinone-containing tricycles. The novel reaction pattern involves tert-butyl aryl(tosyl)methylcarbamates reacting as both electrophile and nucleophile on the same carbon.  相似文献   
945.
An innovative photoresponsive cerasome is fabricated by sol-gel process in combination of self-assembly technique from a molecularly designed organoalkoxysilylated lipid containing an azobenzene unit, which is able to operate as a "valve" with an "on-off" function under specific stimuli to control the release of loaded guest molecules from the liposomal membrane.  相似文献   
946.
In our previous research (Liu et al., J Anal Appl Pyrol 63:303–325, 2002), the pseudo bi-component separated-stage model (PBSM) was suggested for the kinetic analysis on the decomposition of lignocellulosic materials in air at relatively lower heating rates. As a continuing work, this paper is intended to investigate the applicability of PBSM at different heating rates by experimental analyses. Decomposition of oil tea wood has been studied by means of non-isothermal thermogravimetric analysis in air atmosphere at 10–25 K min−1 heating rates. A two-step parallel reaction kinetic model is used to optimize the kinetic parameters of these materials in air. Meanwhile, an improved PBSM is developed to describe the thermal degradation process of oil tea wood. Furthermore, a comparison between the kinetic results of parallel model and PBSM reveals realistic applicability of PBSM. It is concluded that the PBSM has relatively high accuracy for the first decomposition step in the lower temperature range, while fails to predict the thermal decomposition behavior in the char oxidative process which occurs in the higher temperature range.  相似文献   
947.
Phytohemical investigation on the heartwood of Dalbergia odorifera resulted in the isolation of nine flavonoids. Their structures were elucidated as sativanone (1), (3R)-vestitone (2), (3R)-2',3',7-trihydroxy-4'-methoxyisoflavanone (3), (3R)-4'-methoxy-2',3,7-trihydroxyisoflavanone (4), carthamidin (5), liquiritigenin (6), isoliquiritigenin (7), (3R)-vestitol (8), and sulfuretin (9) based on their spectral data. All compounds were evaluated for their inhibitory activity against Ralstonia solanacearum. This is the first report about anti-R. solanacearum activity of the compounds from D. odorifera.  相似文献   
948.
Twelve novel acenaphthene derivatives have been synthesized. The structures of all compounds were confirmed by 1H-NMR, MS and elemental analysis. Their antitumor activities were evaluated in six human solid tumor cell lines, namely non-small cell lung cancer (H460), human colon adenocarcinoma (SW480), human breast cancer cell (MDA-MB-468 and SKRB-3), human melanoma cell (A375) and human pancreatic cancer (BxPC-3). Among them, compound 3c shows the best antitumor activity against SKRB-3 cell line, as high as the positive control adriamycin.  相似文献   
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