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81.
Based on the first ionization chamber (IC) prototype, the structure, working gas component and electrode material of the IC are improved. The test of the improved IC shows that the plateau length is about 2000 V, the plateau slope is less than 0.2%/100 V, the sensitivity is 19.6 pA/rad·h-1, the up-limitation of the linearity can be up to 3.6×105 rad/h, and the applied voltage can be operated to 3500 V. The test results show that the performance of the improved IC meets the requirements of the beam loss monitor. 相似文献
82.
《Analytical letters》2012,45(8):741-750
Abstract The new technique of organoparticulate thermal analysis (OPTA) has been used to investigate the thermal decomposition reactions of various types of organic compounds (i.e., malonic acids, metal acetylacetonates, arenesulfonic acids and their amine salts). With a few exceptions, most of the compounds in these classes exhibit strong organoparticulation characteristics at temperatures below 200°C as indicated by their influence on the output current of an ion chamber detector. In general, no direct correlation between the melting and decomposition temperatures and their organoparticulation temperature ranges (OPTR) was evident. In several instances, the OPTR values lay well above or well beneath the known melting point and decomposition temperatures of the compounds. To explain the organoparticulating properties of these compounds, vapor phase association of polar molecules (such as amines, carboxylic acids, etc.) would appear to be necessary to give organoparticulate sizes detectable with the present instrumentation. Alternatively, the formation of an “aerosol” suspension of organic molecules in gases, such as SO2, CO2, might be occurring with some of these compounds 相似文献
83.
Design and construction of the first prototype ionization chamber for CSNS and PA beam loss monitor (BLM) system 总被引:1,自引:0,他引:1
XU Mei-Hang TIAN Jian-Min CHEN Chang CHEN Yuan-Bo XU Tao-Guang LU Shuang-Tong 《中国物理C(英文版)》2009,33(2):123-126
Design and construction of the first prototype ionization chamber for CSNS and Proton Accelerator (PA) beam loss monitor (BLM) system is reported. The low leakage current (<0.1 pA), good plateau (≈800 V) and linearity range up to 200 Roentgen/h axe obtained in the first prototype. All of these give us good experience for further improving the ionization chamber construction. 相似文献
84.
85.
喷水推进器推力的CFD计算方法研究 总被引:5,自引:1,他引:4
简要介绍获取喷水推进器推力的理论、试验及数值计算(CFD)方法,重点研究采用动量流量法和壁面积分法计算喷水推进器推力的CFD方法。采用多块网格技术,用六面体结构化网格和四面体非结构化网格相结合的混合网格离散计算区域,采用稳态多参考系方法求解RANS方程,对喷水推进器进水流道、叶轮、导叶体和喷口所组成的整个流场进行数值计算。计算中采用了k-ε湍流模型和标准壁面函数,对用动量流量法计算推力方法中所需的假想流管分界面和进口面的求取做了分析,将两种方法计算的推力与厂商提供的推力特性曲线进行了对比。结果表明,采用CFD计算和分析方法来研究喷水推进系统推力性能是可行、可信的。 相似文献
86.
To evaluate the role of salidroside on proliferation,apoptosis and invasiveness of salivary gland adenoid cystic carcinoma cells(SACC),immunocytochemical staining was employed to detect proliferating cell nuclear antigen(PCNA),caspase 3 and caspase 8 expression in SACC-2 cells.Modified Boyden chamber assay combined with laser confocal microscopy(LSCM) was used to evaluate the invasion and migration abilities of SACC-2 cells at different time point.Immunohistochemistry staining revealed that the expression of PCNA was significantly decreased(P0.01) after salidroside treatment.In contrast,salidroside treatment led to increased caspase 3 and caspase 8 in SACC-2 cells.Cell migration depth and number of cells that penetrated Boyden chamber were also decreased by salidroside.Salidroside potently inhibits the proliferation and simultaneously induces the apoptosis of SACC-2 cells.Migration and invasion of SACC-2 cells are also inhibited.Our data throw light on potential clinical application of salidroside to the patients with SACC. 相似文献
87.
密封恒温分光光度法快速测定化学需氧量 总被引:5,自引:0,他引:5
建立了密封恒温消解样品,测定化学需氧量(CDDcr)的分光光度法。应用正交试验法确定了密封恒温法消解试样的最佳条件,此方法有机物的氧化率为98.33%-99.50%。CODcr值在0-800mg/mL范围内符合比耳定律。样品测定的相对标准偏差为0.39%(n=12),加标回收率为97.50%-99.56%。用该法测得的CODcr值与标准回流法所得结果一致。 相似文献
88.
Research on the boron contamination at the p/i interface of microcrystalline silicon solar cells deposited in a single PECVD chamber
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This paper studies boron contamination at the interface between the
p and i layers of μ c-Si:H solar cells deposited in a
single-chamber PECVD system. The boron depth profile in the i layer
was measured by Secondary Ion Mass Spectroscopy. It is found that
the mixed-phase μ c-Si:H materials with 40% crystalline
volume fraction is easy to be affected by the residual boron in the
reactor. The experimental results showed that a 500-nm thick μ
c-Si:H covering layer or a 30-seconds of hydrogen plasma treatment
can effectively reduce the boron contamination at the p/i interface.
However, from viewpoint of cost reduction, the hydrogen plasma
treatment is desirable for solar cell manufacture because the
substrate is not moved during the hydrogen plasma treatment. 相似文献
89.
研究了北京谱仪(BES)Ⅱ带电径迹测量误差矩阵的修正,使运动学拟合TELESIS方法在BESⅡ物理数据分析中得到应用.1)在BESⅡ数据重建程序中,加入了适当的MDC重建单丝分辨率(250μm)和Q修正.2)在TELESIS程序中,放入了BESⅡ有效物质量对BESⅡ误差矩阵进行多次库仑散射和dE/dX能损效应的修正.3)在此基础上,通过J/ψ→μ+μ-的数据样本分析,完成了BESⅡ24×106J/ψ事例RUN-by-RUN的误差矩阵刻度,同时对BESⅡMC数据也作了相应的刻度.经上述误差矩阵修正后,BESⅡ的TELESIS可以较好地满足BESⅡ数据分析工作的要求. 相似文献
90.
M. Czanta C. Strietzel H. J. Besch H. F. Beyer F. Bosch R. Deslattes F. Förster A. Gumberidze G. Hölzer P. Indelicato C. Kozhuharov O. Klepper A. Krämer D. Liesen T. Ludziejewski X. Ma B. Manil G. Menzel N. Pavel A. Simionovici M. Steck T. Stöhlker S. Toleikis J. Tschischgale A. H. Walenta O. Wehrhan 《Hyperfine Interactions》2001,132(1-4):487-490
Crystal spectrometry and absorption edge technique have the capability to overcome the gap in accuracy between experiment
and theory in the strong field domain of QED. New results are presented which indicate the capacity of these methods to measure
the energies of X-rays emitted by highly charged heavy ions at modern storage rings with a precision sensitive to second order
corrections to the Lambshift in H-like very heavy ions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献