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Chemical Research in Chinese Universities 2011年第5期27卷 764-768页

作者： XI Guo-chen hu Shuang BAI Xiao-hong Department of Pharmaceutical Analysis School of Pharmaceutical Science Shanxi Medical University Taiyuan 030001 P. R. China

A method was established using hollow fiber-liquid phase microextraction（HF-LPME） followed by high performance liquid chromatography（HPLC） to determine the concentration of the free（unbound） drug in the solution of the drug and protein. Measurements of drug-protein binding ratios and free drug concentrations were then analyzed with the Klotz equation to determine the equilibrium binding constant and number of binding sites for drug-protein interaction. The optimized method allows one to perform the efficient extraction and separation of free drug from protein-bound drug, protein, and other interfering substances. This approach was used to characterize the binding of the anticholinergic drugs atropine sulfate and scopolamine hydrobromide to proteins in human plasma and bovine serum albumin（BSA）. The results demonstrate the utility of HF-LPME method for measuring free drug concentrations in protein-drug mixtures and determining the protein binding parameters of a pharmacologically important class of drugs.

关键词： Liquid phase microextraction Drug-protein binding ratio Binding parameter Anticholinergic drug

FAULT DIAGNOSIS APPROACH BASED ON HIDDEN MARKOV MODEL AND SUPPORT VECTOR MACHINE

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Chinese Journal of Mechanical Engineering 2007年第5期20卷 92-95页

作者： LIU Guanjun LIU Xinmin QIU Jing hu Niaoqing College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China

Aiming at solving the problems of machine-learning in fault diagnosis, a diagnosis approach is proposed based on hidden Markov model （HMM） and support vector machine （SVM）. HMM usually describes intra-class measure well and is good at dealing with continuous dynamic signals. SVM expresses inter-class difference effectively and has perfect classify ability. This approach is built on the merit of HMM and SVM. Then, the experiment is made in the transmission system of a helicopter. With the features extracted from vibration signals in gearbox, this HMM-SVM based diagnostic approach is trained and used to monitor and diagnose the gearbox＇s faults. The result shows that this method is better than HMM-based and SVM-based diagnosing methods in higher diagnostic accuracy with small training samples.

关键词： Hidden Markov model Support vector machine Fault diagnosis

REE Characteristics of a New Uranium Mineral from the Xianshi Uranium Deposit, South China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1667-1669页

作者： LUO Jincheng hu Ruizhong BI Xianwu CHEN Youwei State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Department of Geological Sciences University of Manitoba

Objective Galuskin et al. （2011） firstly discovered that vorlanite （CaU^6＋/4＋）04 is a rare Ca-rich mineral with a fluorite-type structure, which is isostructural with uraninite （U^4＋O2）. Previous studies of the Xianshi granite-related uranium deposit reported that uraninite and pyrite are the major ore minerals whereas galena, clausthalite （PbSe）, and pyrite are minor phases in the ores. A more detailed petrographic and geochronological study of the uranium minerals from the Xianshi deposit showed that there are three distinct types of uraninite-bearing assemblages which formed at three mineralization episodes （Fig. la; Luo et al., 2015）.

关键词： REE Characteristics of a New Uranium Mineral from the Xianshi Uranium Deposit Ca South China

Multi-scaling Networks from Vertex Intrinsic Fitness

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Communications in Theoretical Physics 2008年第10期50卷 1009-1012页

作者： YANG Shi-Jie WEN Yu-Chua ZHAO hu Department of Physics Beijing Normal University Beijing 100875 China Department of Physics Capital Normal University Beijing 100037 China

Defining and detecting the community structure is an important topic on exploring the complex *** works were mostly based on the so-called modularity method,in which vertices that interconnect to each otherform modules in the *** many real-world networks,however,vertices are grouped not by their connectivity butby their *** demonstrate this idea,we propose a new kind of network,in which the vertices are cataloguedinto several types and are assigned intrinsic *** type of vertices may satisfy a different fitness *** isfound that the whole network exhibits a multi-scaling degree *** clustering coefficients of the subnetworksare modified by the interlinks between vertices in the subnetworks.

关键词： multi-scaling networks fitness

Primary Solidification Phase and Lamellar Orientation in Directionally Solidified Ti-45Al-7Nb Alloy

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Chinese Journal of Aeronautics 2012年第3期25卷 489-492页

作者： YAN Jie ZHENG Lijing XIAO Zhixia YANG Lili ZHANG hu Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Material Science and Engineering Beihang UniversityBeijing 100191China

Primary solidification phase and lamellar orientation are investigated in Ti-45Al-7Nb alloy at very high ratio of temperature gradient to growth rate （G/v） by a liquid-metal-cooled directionally solidified method. It shows that Ti-45Al-7Nb alloy solidifies with primary ct phase. Longitudinal （parallel to growth direction） microstructure shows that a dendrites in solid-liquid mushy zone are discontinuous and transverse mierostructure of a dendrites is worm-like feature. Growth direction of a phase is about 80° away from （0001）,a direction, and close to （1120） a direction. The corresponding lamellar orientation is aligned at the angle of about 10° to growth direction, which is consistent with a-dendrite growth direction according to Blackburn orientation relationship. Therefore, due to the altered growth direction of a phase, the lamellar orientation in Ti-45Al-7Nb alloy is controlled at the G/v ratio of 5 × 10^9 ***^-2.

关键词： metallic material titanium aluminides directional solidification crystal growth lamellar orientation

Dynamic analysis of two-degree-of-freedom airfoil with freeplay and cubic nonlinearities in supersonic flow

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Applied Mathematics and Mechanics(English Edition) 2012年第1期33卷 1-14页

作者： hu-lun GUO Yu-shu CHEN School of Astronautics Harbin Institute of TechnologyHarbin 150001P.R.China

The nonlinear aeroelastic response of a two-degree-of-freedom airfoil with freeplay and cubic nonlinearities in supersonic flows is investigated. The second-order piston theory is used to analyze a double-wedge airfoil. Then, the fold bifurcation and the amplitude jump phenomenon are detected by the averaging method and the multi-variable Floquet theory. The analyticall results are further verified by numerical simulations. Finally, the influence of the freeplay parameters on the aeroelastic response is analyzed in detail.

关键词： freeplay cubic nonlinearity averaging method limit cycle oscillation amplitude jump phenomenon

EFFECT OF ELECTRIC CURRENT PULSE ON SUPERPLASTICITY OF ALUMINIUM ALLOY 7475

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Transactions of Nonferrous Metals Society of China 1996年第1期6卷 77-79,84页

作者： Li Yao Chen Hong Gu Yunqou hu Xinbin Department of Mechanical Engineering Hubei Institute of TechnologyWuhan 430068

The superplastic deformation of aluminium alloy 7475 applied electric current pulse has been *** results presented that applying a high density current pulse raises both the elongation rate and the m value,and makes supperior superplastic properties at high strain rate of 10^(-2)s^(-1),the optimum deformation temperature could move from 530℃to 480~510℃,TEM observation showed the superplastic deformation of the alloy is the results of grain boundary slips and dislocation slips in grains under function of the electron wind;the intergranular tear is a main behavior of fracture of the alloy.

关键词： aluminium alloy 7475 superplasticity electric current pulse

铀对α-Al_(2)O_(3)中氢与本征点缺陷相互作用的影响

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原子与分子物理学报 2025年第5期42卷 123-129页

作者：杨飞龙向鑫胡立张桂凯陈长安中国工程物理研究院材料研究所江油621908

在长期高温服役过程中,铀床的氚渗透泄露问题是聚变堆涉氚系统中需要关注的焦点之一,而一种行之有效的解决思路是在内壁制备阻氚涂层.然而,服役过程中通过热扩散渗入涂层内部的铀可能在阻氚涂层氢行为中起作用,进而影响其服役可靠性.基... 详细信息

在长期高温服役过程中,铀床的氚渗透泄露问题是聚变堆涉氚系统中需要关注的焦点之一,而一种行之有效的解决思路是在内壁制备阻氚涂层.然而,服役过程中通过热扩散渗入涂层内部的铀可能在阻氚涂层氢行为中起作用,进而影响其服役可靠性.基于此,采用第一性原理计算方法,研究了铀对α-Al_(2)O_(3)中氢与本征点缺陷相互作用的影响.结果发现,铀对α-Al_(2)O_(3)中空位型本征点缺陷及氢相关缺陷的存在形式、电荷态及相对稳定性有重要影响.从形成能观点来看,铀对α-Al_(2)O_(3)中空位型本征点缺陷及氢相关缺陷的形成有利,且α-Al_(2)O_(3)中空位型点缺陷对氢的捕陷能力因铀的引入显著增加.研究结果对α-Al_(2)O_(3)基内壁阻氚涂层在氚工艺系统铀床中应用的可靠性评估具有重要的指导意义.

关键词：铀本征点缺陷氢相关缺陷相互作用 α-Al_(2)O_(3)

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Asymptotic Properties of Wavelet Estimators in Partially Linear Errors-in-variables Models with Long-memory Errors

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 77-96页

作者： Hong-chang hu Heng-jian CUI Kai-can LI School of Mathematics and Statistics Hubei Normal University Huangshi 435002 China School of Mathematical science Capital Normal University Beijing 100048 China

While the random errors are a function of Gaussian random variables that are stationary and long dependent, we investigate a partially linear errors-in-variables（EV） model by the wavelet method. Under general conditions, we obtain asymptotic representation of the parametric estimator, and asymptotic distributions and weak convergence rates of the parametric and nonparametric estimators. At last, the validity of the wavelet method is illuminated by a simulation example and a real example.

关键词： partially linear errors-in-variables model nonlinear long dependent time series wavelet estimation asymptotic representation asymptotic distribution weak convergence rates

Model Detection and Variable Selection for Varying Coefficient Models with Longitudinal Data

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Acta Mathematica Sinica,English Series 2016年第3期32卷 331-350页

作者： San Ying FENG Yu Ping hu Liu Gen XUE School of Mathematics and Statistics Zhengzhou University College of Applied Sciences Beijing University of Technology

In this puper, we consider the problem of variabie selection and model detection in varying coefficient models with longitudinM data. We propose a combined penalization procedure to select the significant variables, detect the true structure of the model and estimate the unknown regression coefficients simultaneously. With appropriate selection of the tuning parameters, we show that the proposed procedure is consistent in both variable selection and the separation of varying and constant coefficients, and the penalized estimators have the oracle property. Finite sample performances of the proposed method are illustrated by some simulation studies and the real data analysis.

关键词： Combined penalization longitudinal data model detection variable selection oracle property varying coefficient model