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1.56m望远镜CCD照相机系统的消光系数和转换系数测定 被引量:3
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作者 钱伯辰 陶隽 潘红鉴 《中国科学院上海天文台年刊》 1997年第18期190-195,共6页
测定了1.56m望远镜CCD照相机系统的消光系数和转换系数,消光系数k'和k"列在表1和表2,从观测星等到标准星等的转换系数列在表3。结果表明1.56m望远镜CCD测光系数做绝对测光是有困难的,最好是做相对测光。
关键词 天文望远镜 CCD照相机 CCD测系统 消光系统 转换系数
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系统消光规律的统一代数公式 被引量:4
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作者 钟敦南 申成 《长沙水电师院自然科学学报》 1993年第3期259-265,共7页
本文把晶胞正空间和倒易空间等效点的矩阵表示应用于讨论晶体X光衍射的系统消光规律,给出并证明了适用于所有空间群的系统消光规律的统一的代数表示公式。即:任意一晶胞正空间所对应的倒易空间,其所有的系统消光点中任意一点h必能满足... 本文把晶胞正空间和倒易空间等效点的矩阵表示应用于讨论晶体X光衍射的系统消光规律,给出并证明了适用于所有空间群的系统消光规律的统一的代数表示公式。即:任意一晶胞正空间所对应的倒易空间,其所有的系统消光点中任意一点h必能满足下列两组公式中的一组: h(R_1-Rj)=0 h(R_1-R_j)=0 {hT_j=m+1/2 和{ hT_j=m+1/3 n=2k n=3k其中n为晶胞正空间等效点数目,m与k均为任意整数,j=l,2,……,n中任意一个数。反之亦然。 展开更多
关键词 系统 空间群 晶体
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等效点矩阵与系统消光公式在[Yb(H_2O)(acac)_2(Ac)]_2晶体结构研究中的应用
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作者 申成 钟敦南 《长沙水电师院学报(自然科学版)》 1999年第3期267-270,共4页
在晶体[Yb(H2O)(acac)2(Ac)]2的结构研究中,应用了晶胞空间和倒易空间等效点的矩阵表示与系统消光规律的统一代数公式,确定了其空间群为Pbcn,并用空间群Pbcn验证了系统消光规律的统一代数公式.
关键词 等效点 系统 空间群 晶体结构
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智能化消光比测试系统中的光态分析
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作者 刘贵勤 徐梅芳 《济宁师范专科学校学报》 2000年第6期18-20,共3页
分析了激光束在智能化消光比测试中光态的变化 ,根据测量待测偏光镜透射光强极大值和极小值时测试系统的弥勒矩阵形式不变 ,从而得出光束的状态没有改变 。
关键词 线偏振 弥勒矩阵 智能化比测试系统 学对称性 透射 强度
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地面目标物可见光探测概率规律研究 被引量:8
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作者 冯皓 张军 《解放军理工大学学报(自然科学版)》 EI 2003年第1期93-98,共6页
利用基于气象条件的可见光探测概率方程 ,研究了处于不同地面背景上的目标物在各种气象环境条件下可见光探测概率的变化情况 ,发现在能见度、目标 -背景固有亮度对比度以及太阳高度角等因素的影响下 ,探测概率的变化遵循着一定的规律 。
关键词 可见探测概率 目标-背景固有亮度对比度 天空-地面背景亮度比 可见消光系统 目标探测 军事气象学
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对称群表的系统校验
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作者 金钟声 金松春 +1 位作者 刘永盛 郭东耀 《高等学校化学学报》 SCIE EI CAS 1982年第4期584-586,共3页
本文应用结构因子类型定理,对《X-光晶体学国际表,第一卷》进行了系统较验,其中包括系统消光条件,相角类型及其表达式(一般型、实型、虚型及±π/4型和±3/4π型)对于有错误或不完善的15个空间群,其正误对照列于下表,其它空间... 本文应用结构因子类型定理,对《X-光晶体学国际表,第一卷》进行了系统较验,其中包括系统消光条件,相角类型及其表达式(一般型、实型、虚型及±π/4型和±3/4π型)对于有错误或不完善的15个空间群,其正误对照列于下表,其它空间群都是正确的。 对230个空间群的逐一计算,证明这套定理是满足充分必要条件的。 展开更多
关键词 结构因子 对称群 充分必要条件 系统 空间群 正误对照 晶体学
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应用磁光调制器的高分辨率偏振消光测量系统 被引量:7
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作者 张建华 刘立国 +1 位作者 朱鹤年 林玉侠 《光电子.激光》 EI CAS CSCD 北大核心 2001年第10期1041-1042,共2页
对文献 [1]的自动椭偏仪的部件偏振消光测量系统作了改进 ,用 Verdet常数为 0 .31min/ Oe· cm的铽玻璃作磁光调制材料 ,设计了新型磁光调制器和驱动电路 ,对偏振光进行直流加交流调制 ,结合使用超低噪声选频放大器和锁定放大器 ,... 对文献 [1]的自动椭偏仪的部件偏振消光测量系统作了改进 ,用 Verdet常数为 0 .31min/ Oe· cm的铽玻璃作磁光调制材料 ,设计了新型磁光调制器和驱动电路 ,对偏振光进行直流加交流调制 ,结合使用超低噪声选频放大器和锁定放大器 ,消光角测量的重复性标准差 S3不大于 0 .0 0 0 展开更多
关键词 测量系统 偏振 调制器 高分辨率
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二维晶体的一些晶体学问题研究 被引量:1
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作者 申成 《长沙电力学院学报(自然科学版)》 2004年第3期87-90,共4页
对二维晶体的矩阵表示、对称性及其对X射线衍射的系统消光规律进行了研究,得到并证明了二维晶体的矩阵表示的二个定理和二维晶体对X射线衍射的系统消光定理.
关键词 二维晶体 对称性 矩阵表示 平面群 系统
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P2_1/n空间群的晶体学问题的研究 被引量:2
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作者 申成 《长沙电力学院学报(自然科学版)》 2002年第3期75-77,共3页
研究了P2 1/n空间群从P2 1/c空间群变换而来的方法与结果 .并研究了P2 1/n空间群的对称性、等效点的代数表示。
关键词 P21/n空间群 晶体学 对称性 等效点矩阵 系统规律 归一化结构因子 ε系数 晶体结构
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X射线粉末衍射的发展与应用——纪念X射线粉末衍射发现一百年(续前)
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作者 马礼敦 《理化检验(物理分册)》 CAS 2017年第1期33-41,共9页
3.3粉末衍射法测定晶体结构 3.3.1早期情况 晶体结构测定大致上可分为3大步:第一步,主要依据衍射谱上各衍射线的位置对各衍射线的指数进行标定(简称指标化),并据此推定晶胞参数和依据衍射指数呈现的系统消光来推定其所属的可能空间... 3.3粉末衍射法测定晶体结构 3.3.1早期情况 晶体结构测定大致上可分为3大步:第一步,主要依据衍射谱上各衍射线的位置对各衍射线的指数进行标定(简称指标化),并据此推定晶胞参数和依据衍射指数呈现的系统消光来推定其所属的可能空间群;在此基础上进入第二步,主要求出与各衍射线对应的相位,对衍射强度进行傅里叶变换,以求取各原子在晶胞中的位置参数;开始得到的是不完整、精度不高的结构模型,经过多次迭代计算, 展开更多
关键词 晶体结构 衍射线 衍射谱 晶胞参数 衍射指数 系统 衍射强度 X射线粉末衍射 结构模型 粉末衍射法
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乙酰基二茂铁的晶体和分子结构 被引量:1
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作者 刘启旺 胡玉才 +1 位作者 李逢泽 黄锦顺 《物理化学学报》 SCIE CAS 1986年第1期68-72,共5页
乙酰基二茂铁是按付氏酰基化反应制备的,在CHCl溶剂中培养得到血红色柱状晶体,经元素分析及结构分析共分子式为CHOFe。在CAD4-四园衍射仪上用Mo K射线以θ—2θ扫描在3°≤2θ≤56°范围收集衍射数据。
关键词 晶体 夹角 分子结构 乙酞基 键角 化学键 系统 键长 CP 几何构型 原子 分子
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In vivo and in situ detection of colorectal cancer using Fourier transform infrared spectroscopy 被引量:3
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作者 Qing-BoLi ZhiXu +9 位作者 Neng-WeiZhang LiZhang FanWang Li-MinYang Jian-ShengWang SuZhou Yuan-FuZhang Xiao-SiZhou Jing-SenShi Jin-GuangWu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第3期327-330,共4页
AIM: Real-time and rapid Identification of the malignant tissue can be performed during or before surgical operation. Here we aimed to detect in vivo and in situ colorectal cancer by using Fourier transform infrared (... AIM: Real-time and rapid Identification of the malignant tissue can be performed during or before surgical operation. Here we aimed to detect in vivo and in situ colorectal cancer by using Fourier transform infrared (FTIR) spectroscopy and fiber-optic technology. METHODS: A total of five patients with large intestine cancer were detected in vivo and in situ. Of them, three cases of colon cancer and one case of cecum cancer were detected intraoperatively and in vivo by using a FTIR spectrometer during surgical operation, and one case of rectum cancer was explored non-invasively and in vivo before the surgical operation. Normal and malignant colorectal tissues were detected in vivo and in situ using FTIR spectroscopy on the basis of fundamental studies. RESULTS: There were significant differences between FTIR spectra of normal and malignant colorectal tissues detected in vivo and in situ. Experimental results revealed that the spectral characteristics of normal and malignant tissues found in vivo and in situ were similar to those obtained from in vitro measurement in our previous fundamental research. CONCLUSION: FTIR fiber-optic attenuated total reflectance (ATR) spectroscopy can identify in situ and in vivo colorectal cancer. FTIR spectroscopie method with fiber optics is a non-invasive, rapid, accurate and in vivo cancer detection technique in clinical diagnosis. 展开更多
关键词 Colorectal cancer Fourier transform infrared spectroscopy
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Potential oxidative stress in children with chronic constipation 被引量:2
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作者 Jun-FuZhou Jian-GuoLou +1 位作者 Sheng-LiZhou Ji-YueWang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第3期368-371,共4页
AIM: To investigate the potential oxidative stress in children with -chronic constipation and to explore its mechanisms.METHODS: Seventy children with chronic constipation and 70 age- and sex-matched healthy children ... AIM: To investigate the potential oxidative stress in children with -chronic constipation and to explore its mechanisms.METHODS: Seventy children with chronic constipation and 70 age- and sex-matched healthy children were enrolled in a randomized controlled study. Plasma levels of vitamins C and E, activities of superoxide dismutase and catalase and lipoperoxide level in erythrocytes were determined by spectrophotometry.RESULTS: Compared with healthy children whose vitamin C,vitamin E, superoxide dismutase, catalase and lipoperoxide were 58.35±14.42 μmol/L, 27.15±6.55 μmol/L, 2 206±171U/(g· Hb), 327.3±82.2 K/(g·Hb) and 19.18±4.27 nmol/(g·Hb)respectively, the levels of vitamin C, vitamin E, the activity of superoxide dismutase, and catalase in the children with chronic constipation significantly decreased [46.59±11.51 μmol/L,20.65±4.80 μmol/L, 1943±147 U/(g·Hb) and 269.3±67.8 K/(g·Hb),respectively P<0.01], while the lipoperoxide significantly increased [25.22±5.01 nmol/(g·Hb), P<0.01]. With a prolonged course of disease, the levels of vitamin C, vitamin E, the activity of superoxide dismutase and catalase in the children with chronic constipation gradually decreased,while the level of lipoperoxide gradually increased.CONCLUSION: Chronic constipation can cause potential oxidative stress in children. 展开更多
关键词 Chronic constipation Potential oxidative stress SPECTROPHOTOMETRY
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利用粉晶衍射数据精测点阵参数计算程序
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作者 刘俊所 关雅先 《吉林大学学报(地球科学版)》 EI CAS 1986年第4期85-92,共8页
本文着重讨论了利用粉晶数据进行晶体点阵参数的计算问题(PDOLC)。计算程序采用外推最小二乘拟合技术,外推函数任选,作了详细的系统消光处理,分别估计了六个点阵参数的精度,适用于用各种粉晶方法获得的衍射数据处理。
关键词 衍射方法 晶体点阵 系统
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Spectral and Energy Efficiency of Downlink MU-MIMO Systems with MRT 被引量:4
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作者 Weiqiang Tan Shi Jin Jide Yuan 《China Communications》 SCIE CSCD 2017年第5期105-111,共7页
This paper studies the achievable spectral efficiency(SE)of downlink multiuser multiple-input-multiple-output(MIMO)system,where the base station(BS)is deployed an arbitrary finite antenna number and communicates simul... This paper studies the achievable spectral efficiency(SE)of downlink multiuser multiple-input-multiple-output(MIMO)system,where the base station(BS)is deployed an arbitrary finite antenna number and communicates simultaneously with many users. We assume that the BS has accurate channel state information(CSI)and adopt maximum ratio transmission(MRT)precoding. An accurate analytical result for the achievable SE is obtained. Based on the analytical result on the achievable SE,we further study the achievable energy efficiency(EE)of multiuser MIMO system by considering an energy consumption model. Results indicate that the increasing number of BS antennas can boost the achievable SE of system,whilst the achievable SE tends to a saturated rate in the high signal-tonoise ratios(SNR)regime. Furthermore,an important conclusion is that the increasing number of users is beneficial for the achievable EE and there is an optimal antenna number to maximize the EE of system. 展开更多
关键词 energy efficiency multiuser MIMO maximum ration transmission spectral efficiency
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Load Management Scheme Using Air Conditioning Electric Power Consumption and Photovoltaic Power System Generation
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作者 Zvonimir Klaic Damir Sljivac Kresimir Fekete Zorislav Kraus 《Journal of Energy and Power Engineering》 2014年第11期1926-1932,共7页
In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same ti... In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same time, power consumption is continuously increasing, and consumers are becoming more complex, which ultimately requires new investments in the distribution network. Concept of smart grids is generally accepted as a possible solution. Smart grid is a concept with many elements, where monitoring and control of every element in the chain of production, transmission, distribution and final consumption enable much more efficient delivery and use of electricity. One of the elements of smart grid efficiency is the ability of real-time demand-supply balancing. This balancing is carried out by monitoring of consumption and redistribution of electricity among individual end users, according to their needs. The aim of this paper is creating algorithm for real-time load management using power measurements. Algorithm for real-time load management at the ETFOS (Faculty of Electrical Engineering in Osijek), Croatia is created based on measurements of photovoltaic power plant production, the power consumption of air conditioning system and the faculty building total electricity consumption. Expected result of real-time re-dispatching of air conditioners consumption, depending on the level of electricity production in photovoltaic power plant is decreasing peak demand of the faculty. 展开更多
关键词 Photovoltaic power plant smart grid load management air conditioning system power measurements.
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Correlation between the molecular structure and transcis isomerization characteristics of azobenzenes
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作者 HAN Mina HONDA Takumu 《Science China Chemistry》 SCIE EI CAS 2011年第12期1955-1961,共7页
Photochemical and thermal isomerization of various azobenzenes was systematically investigated to understand the correlation between the molecular structure and trans → cis isomerization characteristics of azobenzene... Photochemical and thermal isomerization of various azobenzenes was systematically investigated to understand the correlation between the molecular structure and trans → cis isomerization characteristics of azobenzenes. A blue shift in π-π absorption band of ortho-alkylated azobenzenes (1o and 2o) was observed together with a reduction in molar extinction coefficient (e) in comparison with both meta-alkylated azobenzenes (4m and 5m) and 7p lacking the meta and ortho substituents. For orthoalkylated azobenzene, photochemical trans-to-cis isomerization and thermal back cis-to-trans isomerization in solution oc- curred slowly when compared with 4m, 5m and 7p. The half-life time of the cis form of 20 was found to be 380 h, which is about 8-50 times longer than those of comparable 4m, 5m (43-13 h) and 7p (7 h). Furthermore, comparison of the molecular structure and isomerization characteristics of azobenzene thiol (20 and 5m) self-assembled monolayers on flat gold surfaces indicates that the trans-to-cis photoconversion in monolayer systems is influenced by steric hindrance and strong intermoleculax interaction between azobenzene units. 展开更多
关键词 AZOBENZENE ISOMERIZATION lifetime of cis form molecular structure
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Extinction Effects of Multiplicative Non-Gaussian L′evy Noise in a Tumor Growth System with Immunization
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作者 郝孟丽 徐伟 +1 位作者 李东喜 刘迪 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第5期571-577,共7页
The extinction phenomenon induced by multiplicative non-Gaussian L′evy noise in a tumor growth model with immune response is discussed. Under the influence of the stochastic immune rate, the model is analyzed in term... The extinction phenomenon induced by multiplicative non-Gaussian L′evy noise in a tumor growth model with immune response is discussed. Under the influence of the stochastic immune rate, the model is analyzed in terms of a stochastic differential equation with multiplicative noise. By means of the theory of the infinitesimal generator of Hunt processes, the escape probability, which is used to measure the noise-induced extinction probability of tumor cells, is explicitly expressed as a function of initial tumor cell density, stability index and noise intensity. Based on the numerical calculations, it is found that for different initial densities of tumor cells, noise parameters play opposite roles on the escape probability. The optimally selected values of the multiplicative noise intensity and the stability index are found to maximize the escape probability. 展开更多
关键词 model of tumor growth stochastic immune rate non-Gaussian L6vy motion noise-induced ex-tinction probability
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A kind of denoising method for airborne waveform sampling LiDAR
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作者 董志伟 张瑞环 +3 位作者 孙立羽 陈兆东 樊荣伟 陈德应 《Optoelectronics Letters》 EI 2017年第5期397-400,共4页
This paper describes a full waveform sampling LiDAR system applying stripe principle. A kind of denoising method based on edge detection of original stripe signal is proposed. This method is compared with other denois... This paper describes a full waveform sampling LiDAR system applying stripe principle. A kind of denoising method based on edge detection of original stripe signal is proposed. This method is compared with other denoising methods, such as Wiener filtering, mean filtering and median filtering. It is found that the proposed denoising method is much more effective for dealing with the waveform signals. 展开更多
关键词 Edge detection Optical radar
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