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Structure of BaGd_2(MoO_4)_4 Crystal

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Chinese Journal of Structural Chemistry 2007年第3期26卷 328-332页

作者： ZHAO Dan LIN Zhou-Bin wang guo-fu State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The title compound belongs to monoclinic, space group C2/c with a = 5.2694（1）, b = 12.6659（4）, c = 19.4108（2） A,β= 91.504（2）°, V = 1295.06（5） A^3, Z = 4 and Dc= 5.599 g/cm^3. The structure of BaGd2（MoO4）4 contains a MoO4 tetrahedron, a distorted GdO8 polyhedron, and Ba^2＋ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices, thus-forming a new Gd-Mo layer. Finally, the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 A, this structural characteristic will result in a cleavage along the （001） plane.

关键词： Czochralski method BaGd2(MoO4)4 crystal

Structure of GdMg(BO_2)_5 Crystal

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Chinese Journal of Structural Chemistry 2006年第6期25卷 709-713页

作者： FAN Jun-Mei LIN Zhou-Bin ZHANG Li-Zhen wang guo-fu State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The title compound GdMg（BO2）s crystallizes in monoclinic, space group P21/n with a = 8.6230（17）, b = 7.5860（15）, c = 9.3777（19） A, β= 93.19（3）°, V = 612.5（2） A3, Z = 4, Mr = 395.61, De= 4.290 g/cm^3,μ = 10.987 mm^-1, F（000） = 724, the final R = 0.0135 and wR= 0.0355 for 1373 observed reflections with I 〉 2σ（I）. The structure consists of BO3 triangles, BO4 tetrahedra, MgO6 distortion octahedra and GdO10 polyhedra. furthermore, BO3 triangles and BO4 tetrahedra have been verified by infrared spectra. The Gd atoms form infinite zigzag chains along the b axis with the shortest distance of Gd--Gd being 3.958 A. The shorter Gd--Gd will result in a strong interaction between active ions and a large fluorescence concentration quenching effect.

关键词： crystal structure GdMg(BO2)5 crystal

Growth and Spectroscopic Properties of Nd^(3+):Sr_3Gd_2(BO_3)_4 Crystal

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1039-1042页

作者： ZHANG Yan wang guo-fu LIN Zhou-Bin ZHANG Li-Zhen School of Materials Science and Engineering Shanghai Institute of Technology Shanghai 200235 China fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fufian 350002 China

This paper reports the growth, X-ray diffraction and spectroscopy of Nd3＋：Sr3Gd2（BO3）4 crystal. A Nd3＋：Sr3Gd2（BO3）4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3＋：Sr3Gd2（BO3）4 crystal belongs to the orthorhombic system, space group Pnma （D2h） with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3＋：Sr3Gd2（BO3）4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.

关键词： Nd3+:Sr3Gd2(BO3)4 crystal growth spectroscopic properties

Analysis of China's Haze Days in the Winter Half-Year and the Climatic Background during 1961–2012

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Advances in Climate Change Research 2014年第1期5卷 1-6页

作者： SONG Lian-Chun GAO Rong LI Ying wang guo-fu National Climate Center China Meteorological Administration Laboratory for Climate Studies China Meteorological Administration

The characteristics of haze days and the climatic background are analyzed by using daily observations of haze,precipitation,mean and maximum wind speed of 664 meteorological stations for the period of 1961–*** results show that haze days occur significantly more often in eastern China than in western *** annual number of haze days is 5–30 d in most parts of central-eastern China,with some areas experiencing more than 30 d,while less than 5 d are averagely occurring in western *** days are mainly concentrated in the winter half-year,with most in winter,followed by autumn,spring,and then *** 20%of annual haze days are experienced in *** haze days in central-eastern China in the winter half-year have a significant increasing trend of 1.7 d per decade during 1961–*** were great increases in haze days in the 1960s,1970s and the beginning of the 21st *** was also significant abrupt changes of haze days in the early 1970s and *** 1961 to 2012,haze days in the winter half-year increased in South China,the middle-lower reaches of the Yangtze River,and North China,but decreased in Northeast China,eastern Northwest China and eastern Southwest *** number of persistent haze is *** Longer the haze,the greater the proportion to the number persistent *** climatic conditions exacerbated the occurrence of *** correlation coefficient between haze days and precipitation days in the winter half-year is mainly negative in central-eastern *** precipitation days show a decreasing trend in most parts of China,with a rate of around–4.0 d per decade in central-eastern China,which reduces the sedimentation capacity of atmospheric *** the period of 1961–2012,the correlation coefficients between haze days and mean wind speed and strong wind days are mainly negative in central-eastern China,while there exists positive correlation between haze days and breeze days in the winter ***

关键词： haze winter half-year precipitation days wind speed

Current Status of Forest Medicine Research in China

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Biomedical and Environmental Sciences 2018年第7期31卷 551-554页

作者： HUANG Qing Dong WU Qing MAO Gen Xiang wang San Ying JIA Bing Bing wang guo fu Department of Geriatrics Zhejiang Hospital Zhejiang Provincial Key Lab of Geriatrics

In recent years,due to regional pollution and deteriorating environment,combined with intense social competition and heavier life pressure,an increasing number of people are affected by lifestyle-related diseases and ... 详细信息

关键词： Current Status of Forest Medicine Research in China

Medical Assessment on Forest Therapy Base in Zhejiang Province, China

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Biomedical and Environmental Sciences 2019年第12期32卷 934-937页

作者： WU Qing YE Bing CHEN Zhuo Mei LYU Xiao Ling REN Xiao Xu DONG Jian Hua wang guo fu Geriatrics Institute of Zhejiang Province Zhejiang HospitalHangzhou 310013ZhejiangChina Hangzhou Forestry Academy Hangzhou 310022ZhejiangChina Chinese Academy of Forestry Beijing 100091China Zhejiang Forestry Academy Hangzhou 310023ZhejiangChina

According to the‘13^th Five-Year plan for forestry development’of State Forestry and Grassland Administration,500 forest therapy(also known as forest bathing or Shinrin-yoku in Japan)bases and 5–10 international cooperation demonstration bases will be set up in China,by ***,it’s important to provide evidence about the benefits of specific forest environmental to human health,namely medical assessment on forest therapy base.

关键词： forest bases Forest

A necessary and sufficient condition for generalized admissibility of Bayes estimate

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中国有色金属学会会刊：英文版 2005年第S1期15卷 89-91页

作者： wang guo-fu, ZHU Jian-jun (Central South University, Changsha 410083, China)

A definition of generalized admissibility of Bayes estimates has been given. This generalized admissibility is a rule to identify whether Bayes estimates is acceptable or not under the condition of incorrect prior information. In this paper, a sufficient and necessary condition for the generalized admissibility is derived under quadratic loss. From this we can conclude that, when deviation of prior mean and deviation of prior variance do not go beyond the bound, the Bayes estimation is acceptable and it is discussed that how the deviation of the prior information influences on generalized admissibility. Because the precise distribution of prior information is unknown, the example gives a way to select the prior distribution. The example shows that this method is efficient and feasible.

关键词： Bayes estimate generalized admissibility inaccurate prior quadratic loss Bayes risk

基于BSS的跳频通信抗部分频带噪声阻塞干扰方法

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系统工程与电子技术 2013年第5期35卷 1079-1084页

作者：于淼王曰海汪国富中国人民解放军理工大学江苏南京210007 中国人民解放军总参谋部第六十三研究所江苏南京210007 浙江大学信息科学与电子工程学系浙江杭州310027

根据跳频信号与部分频带噪声阻塞干扰信号的近似统计独立性,提出一种基于盲源分离的跳频通信对抗部分频带噪声阻塞干扰方法。所提方法利用分离信号的二阶或高阶统计量构建目标函数引导分离矩阵迭代,实现跳频信号与部分频带噪声阻塞干扰... 详细信息

根据跳频信号与部分频带噪声阻塞干扰信号的近似统计独立性,提出一种基于盲源分离的跳频通信对抗部分频带噪声阻塞干扰方法。所提方法利用分离信号的二阶或高阶统计量构建目标函数引导分离矩阵迭代,实现跳频信号与部分频带噪声阻塞干扰信号的有效分离,从而提高跳频通信的抗干扰能力。仿真结果表明,所提方法可明显改善跳频通信在部分频带噪声阻塞干扰下的误码率性能,而且分离算法的处理时延很小,有望满足跳频通信的实际需求。

关键词：抗干扰跳频通信盲源分离独立分量分析部分频带噪声阻塞干扰

30m望远镜三镜镜面面形误差的斜率均方根评价

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光学精密工程 2014年第5期22卷 1171-1175页

作者：王富国安其昌中国科学院长春光学精密机械与物理研究所吉林长春130033

由于传统的均方根方法在评价大口径反射镜时难以精确表达光学表面的中空间频率误差,本文提出了基于斜率均方根(SlopeRms)的误差评价方法来评价光学表面面形。该方法先以Zernike多项式拟合光学表面面形,在此基础上求解不同空间间隔上的... 详细信息

由于传统的均方根方法在评价大口径反射镜时难以精确表达光学表面的中空间频率误差,本文提出了基于斜率均方根(SlopeRms)的误差评价方法来评价光学表面面形。该方法先以Zernike多项式拟合光学表面面形,在此基础上求解不同空间间隔上的斜率均方根。这种评价方法可以很好地区分小尺寸磨削工具造成的误差和大口径反射镜在多点支撑下造成的面形误差。文中建立了SlopeRms的数学模型,推导了SlopeRms的计算方法,并以此方法为基础对30m望远镜(TMT)三镜面形进行了评价。结果显示,采用斜率均方根的评价方法得到的光学表面面形值达到0.9μrad,优于传统的RMS评价方法(RMS=115nm),满足设计要求。结果显示,基于斜率均方根的误差评价方法能更加全面和客观地评价大口径反射镜面形,具有实际意义。

关键词：光学检测 30m望远镜表面面形面形误差斜率均方根均方根