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Chinese Chemical Letters 2014年第4期25卷 517-522页

作者： Long Zhang Yang-Ping Wen Yuan-Yuan Yao Zi-Fei Wang xue-min Duan Jing-Kun xu School of Pharmacy Jiangxi Science & Technology Normal University Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University

A simple, sensitive, and reliable method for the voltammetric determination of bisphenol A （BPA） by using carboxylic group functionalized single-walled carbon nanotubes （f-SWCNT）/carboxylic-functionalized poly（3,4-ethylenedioxythiophene）（PC4） complex modified glassy carbon electrode （GCE） has been successfully developed. The electrochemical behavior of BPA at the surface of the modified electrode is investigated by electrochemical techniques. The cyclic voltammetry results show that the as-prepared electrode exhibits strong catalytic activity toward the oxidation of BPA with a well-defined anodic peak at 0.623 V in PBS （0.1 mol/L, pH 7.0）. The surface morphology of the 3D network of composite film is beneficial for the adsorption ofanalytes. Under the optimized conditions, the oxidation peak current is proportional to BPA concentration in the range between 0.099 and 5.794 μmol/L （R2 = 0.9989）, with a limit of detection of 0.032 μmol/L （SIN = 3）. The enhanced performance of the sensor can be attributed to the excellent electrocatalytic property off-SWCNT and the extraordinary conductivity of PC4. Furthermore, the proposed modified electrode displays high stability and good reproducibility. The good result on the voltammetric determination of BPA also indicates that the asfabricated modified electrode will be a good candidate for the electrochemical determination and analysis of BPA.

关键词： Bisphenol A Electrochemical sensor Voltammetric determination Poly(3 4-ethylenedioxythiophene) derivative

Ursolic Acid Prevents Retinoic Acid-Induced Bone Loss in Rats

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Chinese Journal of Integrative Medicine 2019年第3期25卷 210-215页

作者： CHENG min LIANG xu-hua WANG Qing-wei DENG Ya-ting ZHAO Zhi-xin LIU xue-ying College of Biology Pharmacy and Food Engineering Shangluo University Department of Pharmacy The Second Affiliated Hospital Fourth Military Medical University Department of Pharmacology Xi'an Medical College Department of Medicinal Chemistry Fourth Military Medical University

Objective: To examine the effects of ursolic acid(UA) on mitigating retinoic acid(RA)-induced osteoporosis in rats. Methods: Fifty female Sprague-Dawley rats were randomly divided into the control group(n=10) and the osteoporosis group(n=40). The 40 osteoporosis rats were induced by 75 mg/(kg·d) RA once daily for 2 weeks, and then were randomly assigned to vehicle control(model), low-, middle-, and high-dose UA [(UA-L, UA-M, UA-H; 30, 60, 120 mg/(kg·d), respectively] groups(10 rats each). UA were administered once daily to the rats from the 3 rd weeks for up to 4 weeks by gavage. Bone turnover markers [serum alkaline phosphatase(ALP), osteocalcin(OCN), urine deoxypyridinoline(DPD)] and other parameters, including serum calcium(S-Ca), serum phosphorus(S-P), urine calcium(U-Ca), urine phosphorus(U-P), and bone mineral density(BMD) of the femur, 4 th lumbar vertebra and tibia, bone biomechanical properties and trabecular microarchitecture, were measured. Results: The osteoporosis in rats was successfully induced by RA. Compared with the model group, UA-M and UA-H significantly reversed the RA-induced changes in S-P, U-Ca, U-P, ALP, OCN and urine DPD ratio and markedly enhanced the BMD of right femur, 4 th lumbar vertebra and tibia(P<0.05 or P<0.01). Further, biomechanical test and microcomputed tomography evaluation also showed that UA-H drastically improved biomechanical properties and trabecular microarchitecture(P<0.05 or P<0.01). Conclusion: UA could promote bone formation, increase osteoblastic activity and reduce osteoclastic activity in rats, indicating that UA might be a potential therapeutic of RA-induced acute osteoporosis.

关键词： osteoporosis bone turnover ursolic acid bone mineral density biomechanics microcomputed tomography

Synthesis and Biological Activities of α-Amino Acylamines Derivatives Containing Furan and Pyridine Ring

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Chemical Research in Chinese Universities 2009年第6期25卷 846-850页

作者： xu Yan~ xue Si-jia Department of Chemistry Shanghai Normal University Shanghai 200234 P R. China

In order to find better herbicidal activity and fungicidal activity of a-amino acid derivatives, we introduced furan rings and pyridyl groups to seven different a-amino acids to form a series of 14 novel a-amino acylamines derivatives via dicyclohexylcarbodiimide/4-dimethylaminopyridine（DCC/DMAP） coupling method. The structures of all the compounds prepared were confirmed by IR, LC/MS, IH NMR, and elemental analysis. The herbicidal and fungicidal results show that some compounds containing glycine and valine substrate have good activities.

关键词： Amino acid Furan ring Pyridyl group Herbicidal and fungicidal activity

A Backstepping Simple Adaptive Control Application to Flexible Space Structures

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Chinese Journal of Aeronautics 2012年第3期25卷 446-452页

作者： LIU min xu Shijie HAN Chao School of Astronautics Beihang UniversityBeijing 100191China

Although the simple adaptive control （SAC） is widely studied both in theory and application in flexible space structure control and other control problems, it is restricted by the almost strictly positive real （ASPR） conditions. In most practical control problems, the ASPR conditions are not satisfied. Therefore, based on the SAC theory, this paper proposes a backstepping simple adaptive control algorithm which suits the system with arbitrary relative degree with no need of parallel feed forward compensa- tor. The proposed control algorithm consists of decomposition of the arbitrary relative degree system into a known subsystem and an unknown ASPR subsystem which are connected in cascade, design of constant output feedback controller for the known subsystem, and implementation of backstepping method and SAC of the unknown ASPR subsystem. Inheriting the characteristics of the SAC, this method can be adaptive online for the parameter uncertainties. Then, the application of the proposed controller to large flexible space structure with collocated sensors and actuators is studied, and the simulation results validate the proposed controller. It is a new strategy to apply the classical SAC to high relative degree plants.

关键词： simple adaptive control almost strictly positive real backstepping flexible structure intermediate control law

Exergy analysis and performance enhancement of isopropanol-acetone-hydrogen chemical heat pump

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Frontiers in Energy 2017年第4期11卷 510-515页

作者： min xu Jun CAI Xiulan HUAI Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China

Exergy loss analysis was conducted to identify the irreversibility in each component of the isopropanol- acetone-hydrogen chemical heat pump （IAH-CHP）. The results indicate that the highest irreversibility on a system basis occurs in the distillation column. Moreover, the effect of operating parameters on thermodynamic performances of the IAH-CHP was studied and the optimal conditions were obtained. Finally, the potential methods to reduce the irreversibility of the IAH-CHP system were investigated. It is found that reactive distillation is apromising alternative. The enthalpy and exergy efficiency of the IAH-CHP with reactive distillation increases by 24.1% and 23.2%, respectively.

关键词： waste heat reuse chemical heat pump exergyanalysis isopropanol

Complete Proof Systems for Amortised Probabilistic Bisimulations

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Journal of Computer Science & Technology 2016年第2期31卷 300-316页

作者： Li-Li xu Hui-min Lin State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Ecole P olytechnique P alaiseau 91120 France

The notion of amortisation has been integrated in quantitative bisimulations to make long-term behavioral comparisons between nondeterministic systems. In this paper, we present sound and complete proof systems for amortised strong probabilistic bisimulation and its observational congruence on a process algebra with probability and nondeterminism, and prove their soundness and completeness. Our results make it possible to reason about long-term （observable） probabilistic behaviors by syntactic manipulations.

关键词： axiomatization probabilistic calculus for communication systems (CCS) probabilistic automata amortisedbisimulation

THE CONDITIONAL DIAGNOSABILITY OF SHUFFLE-CUBES

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Journal of Systems Science & Complexity 2010年第1期23卷 81-90页

作者： min xu Xiaodong HU Songpu SHANG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China Institute of Applied Mathematics MADIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China College of Mathematics and Information Science North China University of Water Conservancy and Electric Power Zhengzhou Henan 450008 China

In the application of multiple-processor systems some processors or links in a system maynot function properly,thus the fault diagnosis is one of the most important issues in the analysisand maintenance of those *** the practical fault diagnosis systems,the probability that allneighboring processors of a processor are faulty simultaneously is very ***,the conditionaldiagnosability,which is a new metric for evaluating such systems,assumes that every fault set doesnot contain all neighbors of any processor in the *** this paper,the authors show that then-dimensional shuffle-cube has the conditional diagnosability of 4n-15 for n = 2 (mod 4) and n ≥ 10.

关键词： Conditional diagnosability fault diagnosis shuffle-cubes.

A novel and facile synthesis of 2-oxo-1,2-dihydropyridine-fused 1,3-diazaheterocycles via heterocyclic ketene aminals and Konevenagel adducts formed by phthalic anhydride and ethyl cyanacetate

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Chinese Chemical Letters 2014年第12期25卷 1515-1519页

作者： min-ming Zou Feng-Juan Zhu xue Tian Li-Ping Ren xu-Sheng Shao Zhong Li Shanghai Key Laboratory of Chemical Biology School of PharmacyEast China University of Science and Technology

An efficient synthetic pathway to 2-oxo-1,2-dihydropyridine-fused 1,3-diaza heterocycles from heterocyclic ketene aminals,phathalic anhydride and ethyl cyanacetate was *** protocol involved aza-ene reaction/imine-enam... 详细信息

关键词： Heterocyclic ketene aminals 2-Oxo-1 2-dihydropyridine 1 3-Diazaheterocycle Synthesis

High Temperature Catalytic Hydrogenation of Acetone over Raney Ni for Chemical Heat Pump

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Journal of Thermal Science 2014年第1期23卷 85-90页

作者： DUAN Yanjun xu min HUAI Xiulan Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Exothermic hydrogenation reaction of acetone is an important part of an IAH-CHP, and the performance of IAH-CHP is affected directly by this reaction. This paper studies the influence of space velocity, temperature, hydrogen flow rate and pressure on conversion and selectivity experimentally. The byproducts are analyzed and classified into three types: hydrogenation product, cracking products and condensation products. Both the conversion and selectivity of this reaction have the same trend with the change of space velocity, temperature and hydrogen flow rate, and has the opposite trend with the change of pressure. As the space velocity increases, the conversion curve is a gradual decline parabola but the selectivity curve is close to a straight line. Hydrogen flow rate has a more obvious influence on conversion than temperature, whereas on selectivity the situation is opposite. High pressure increases the conversion of acetone to all products, but the increment of byproducts is more than that of isopropanol, so the selectivity decreases as pressure increases.

关键词： Chemical heat pump Raney Ni Hydrogenation Acetone Conversion Selectivity

Micro-mechanism of metal magnetic memory signal variation during fatigue

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International Journal of minerals,Metallurgy and Materials 2014年第3期21卷 259-265页

作者： ming-xiu xu Zhang-hua Chen min-qiang xu School of Mathematics and Physics University of Science and Technology Beijing Division of Vehicle Dynamics & Control Harbin Institute of Technology

Tensile fatigue tests were designed to study the relation between the tangential magnetic memory signal and dislocations. According to experimental results, in the early stage of fatigue, the magnetic signal and the dislocation density rapidly increase; while in the middle stage, the magnetic signal gradually increases, the dislocation density remains steady, and only the dislocation structure develops. On the other hand, in the later stage, the magnetic signal once again increases rapidly, the dislocation structure continues to develop, and microscopic cracks are formed. Analysis reveals that the dislocations block the movement of the domain wall, and the area of dislocation accumulation thus becomes an internal magnetic source and scatters a field outward. In addition, the magnetic memory field strengthens with increasing dislocation density and complexity of the dislocation structure. Accordingly, the dislocation pinning factor related with the dislocation density and the dislocation structure has been proposed to characterize the effect of dislocations on the magnetic memory signal. The magnetic signal strengthens with an increase in the dislocation pinning factor.

关键词： fatigue of materials metal magnetic memory dislocations magnetic fields