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Present status of research on space optical remote sensors at CIOMP

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光学精密工程 2003年第3期11卷 213-222页

作者： WANG Jia-qi HAN chang-yuan changchunInstituteofOptics FineMechanicsandPhysicsChineseAcademyofSciencesChangchun130022China

This paper is to review our space optical remote sensor(SORS) technologies including optical materials, optics fabrication and coating, optical testing, system assembly and final testing, and space environment simulation experiment conducted in our institute. The primary parts of the fabrication and testing facilities and results are described in detail.

关键词：空间光学遥感传感器光学材料光学系统 SORS CIOMP 光学遥感

Bifurcation and chaos in high-frequency peak current mode Buck converter

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Chinese Physics B 2016年第7期25卷 171-178页

作者：常昌远赵欣杨帆吴承恩 School of Integrated Circuit Southeast University

Bifurcation and chaos in high-frequency peak current mode Buck converter working in continuous conduction mode（CCM） are studied in this paper. First of all, the two-dimensional discrete mapping model is established. Next, reference current at the period-doubling point and the border of inductor current are derived. Then, the bifurcation diagrams are drawn with the aid of MATLAB. Meanwhile, circuit simulations are executed with PSIM, and time domain waveforms as well as phase portraits in i_L–v_C plane are plotted with MATLAB on the basis of simulation data. After that, we construct the Jacobian matrix and analyze the stability of the system based on the roots of characteristic equations. Finally, the validity of theoretical analysis has been verified by circuit testing. The simulation and experimental results show that,with the increase of reference current I_（ref）, the corresponding switching frequency f is approaching to low-frequency stage continuously when the period-doubling bifurcation happens, leading to the converter tending to be unstable. With the increase of f, the corresponding Irefdecreases when the period-doubling bifurcation occurs, indicating the stable working range of the system becomes smaller.

关键词： peak current mode Buck converter high frequency bifurcation chaos

Quantifying groundwater recharge and discharge for the middle reach of Heihe River of China using isotope mass balance method

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Journal of Groundwater Science and Engineering 2021年第3期9卷 225-232页

作者： Han Zhang Zong-yu Chen chang-yuan Tang Key Laboratory of Groundwater Sciences and Engineering Ministry of Natural ResourcesZhengding 050803Hebei ProvinceChina. Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China. Chiba University Chiba 2718510Japan.

The study aims to identify a suitable site for open and bore well in a farmhouseusing ground magnetic survey in south *** also aims to define depth to granitoid and structural elements which traverse the selected *** data(n=84)measured,processed and interpreted as qualitative and *** results of total magnetic intensities indicate that the area is composed of linear magnetic lows trending NE-SW direction and circular to semi-circular causative *** magnetic values ranged from-137 nT to 2345 nT with a mean of 465 *** to equator shows significant shifting of causative bodies in the southern and northern *** signal map shows exact boundary of granitic *** directional filter has brought out structural element trending NE-SW *** of individual profile brought to light structurally weak zone between 90 m and 100 m in all the profile *** decrease of magnetic values from 2042 nT to 126 nT noticed in profile line 6 between 20 m and 30 m indicates fault *** breaks obtained from these maps were visualized,interpreted and identified two suitable sites for open and bore *** averaged power spectrum estimates depth of shallow and deep sources in 5 m and 50 m,*** method has also been applied to estimate depth of granitoid and structural elements using structural indexes 0,1,2,and 3 and found depth ranges from90 *** indicates magnetic method is one of the geophysical methods suitable for groundwater exploration and site selection for open and borewells.

关键词： Arid region Stable isotopes Water budget Surface water-ground water interaction

Parkinsonian oscillations and their suppression by closed-loop deep brain stimulation based on fuzzy concept

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Chinese Physics B 2022年第12期31卷 684-691页

作者： Xi-Le Wei Yu-Lin Bai Jiang Wang Si-yuan chang Chen Liu School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China

This paper provides an adaptive closed-loop strategy for suppressing the pathological oscillations of the basal ganglia based on a variable universe fuzzy *** pathological basal ganglia oscillations in the theta(4-9 Hz)and beta(12-35 Hz)frequency bands have been demonstrated to be associated with the tremor and rigidity/bradykinesia symptoms in Parkinson’s disease(PD).Although the clinical application of open-loop deep brain stimulation(DBS)is effective,the stimulation waveform with the fixed parameters cannot be self-adjusted as the disease progresses,and thus the stimulation effects go *** deal with this difficult problem,a variable universe fuzzy closed-loop strategy is proposed to modulate different PD *** establish a cortico-basal ganglia-thalamocortical network model to simulate pathological oscillations and test the control *** results suggest that the proposed closed-loop control strategy can accommodate the variation of brain states and symptoms,which may become an alternative method to administrate the symptoms in PD.

关键词： deep brain stimulation Parkinson’s disease basal ganglia closed-loop control variable universe fuzzy

Tracing runoff components in the headwater area of Heihe River by isotopes and hydrochemistry

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Journal of Groundwater Science and Engineering 2022年第4期10卷 405-412页

作者： Han Zhang Zong-yu Chen chang-yuan Tang Key Laboratory of Groundwater Sciences and Engineering Ministry of Natural Resources.Zhengding 050803HebeiChina Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Comprehensive Survey and Management Center for Natural Resources China Geological SurveyBeijing 100055China Chiba University Matsudo 6482718510ChibaJapan

Since water resources of the Heihe River Basin are primarily in the form of surface runoff in the Qilian Mountains,identifying its sources and components is essential for researchers to understand water cycling and transformation in the *** will help to properly exploit water resources,and contribute to ecological environment *** paper uses the isotope data of hydrogen and oxygen in water and hydrochemistry data collected at a high altitude to trace the sources of surface runoff in Heihe River in rainy season and uses the three-component mixing model to estimate the contribution of each component to *** indicate that surface water consists of precipitation,melt water and groundwater,with precipitation being the primary component and contributing to 59%-64%of *** water and groundwater account for 15%-25%and 12%-22%,*** accounts for 60%,groundwater for 22%and glacial melt water for 18%of the outflow in the main stream of the Heihe *** composition is of great significance for water cycling and conversion research as well as water resource evaluation and management.

关键词： Qilian Mountains Components of surface runoff Isotope Mixing model

A new ent-labdane diterpenoid lactone from Andrographis paniculata

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Chinese Chemical Letters 2010年第5期21卷 587-589页

作者： Xiao Chi Ma Zhan Ping Gou chang yuan Wang Ji Hong Yao Xiu Lan Xin yuan Lin Ke Xin Liu School of Pharmacy Dalian Medical UniversityDalian 116044China School of Pharmacology Guangdong Medical CollegeDongguan 523808China Biotechnology Application Center Beijing Vocational College of Electronic Science and TechnologyBeijing 100029China

A new ent-labdane diterpenoid lactone was isolated from Andrographis *** structure was identified on the basis of spectral data including 2D NMR.

关键词： Andrographis paniculata Ent-labdane diterpenoid Lactone

On Integrals Involving Universal Associated Legendre Polynomials and Powers of the Factor (1-x^2) and Their Byproducts

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Communications in Theoretical Physics 2016年第10期65卷 369-373页

作者： Dong-Sheng Sun yuan You Fa-Lin Lu chang-yuan Chen Shi-Hai Dong School of New Energy and Electronics Yancheng Teachers University Yaneheng 224002 China CIDETEC Instituto Politecnico Nacional Adolfo Lpez Mateos CDMX C.P. 07700 Mexico

The associated Legendre polynomials play an important role in the central fields,but in the case of′the non-central field we have to introduce the universal associated Legendre polynomials P^m'l_′(x) when studying the modified Pschl-Teller potential and the single ring-shaped *** present the evaluations of the integrals involving the universal associated Legendre polynomials and the factor(1-x^2)^(-p-1) as well as some important byproducts of this integral which are useful in deriving the matrix elements in spin-orbit *** calculations are obtained systematically using some properties of the generalized hypergeometric series.

关键词： universal associated-Legendre polynomials generalized hypergeometric series parity

Alkaline pretreatment for chlorine removal from high-chlorine rhodochrosite

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1252-1257页

作者： Xing-ran Zhang Zuo-hua Liu Wen-sheng Li Ya-ya Cheng Jun Du chang-yuan Tao Chongqing Key Laboratory of Chemical Process for Clean-Energy and Resource Utilization College of Chemistry and Chemical EngineeringChongqing University

Chloride in manganese ore adversely affects mineral extraction. The mechanisms and the factors that influence an alkali pretreatment to removal chlorine from manganese ore were explored to eliminate hazards posed by chlorine during the electrolysis of manganese. The results showed that sodium carbonate, when used as an alkaline additive, promoted the dissolution of insoluble chloride, enhanced the migration of chloride ions, and effectively stabilized Mn^（2＋）. The optimal conditions were a sodium carbonate concentration of 0.45 mol·L^（-1）, a liquid-solid ratio of 5：1 mL ·g^（-1）, a reaction time of 1 h, and a temperature of 25°C. The chlorine removal efficiency was greater than 95%, and the ore grade（Mn） was increased by 2.7%.

关键词： manganese ore treatment rhodochrosite sodium carbonation pretreatment dechlorination

Membrane-bound O-acyltransferases(MBOATs)

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Frontiers in Biology 2011年第3期6卷 177-182页

作者： Catherine C.Y.chang Jie SUN Ta-yuan chang Department of Biochemistry Dartmouth Medical SchoolHanoverNH 03755 USA

The MBOATenzyme family,identified in 2000,comprises 11 genes in the human genome that participate in a variety of biological *** enzymes contain multiple transmembrane domains and share two active site residues,histidine and *** MBOAT members are drug targets for major human diseases,including atherosclerosis,obesity,Alzheimer disease,and viral *** we review the historical aspects of MBOAT enzymes,classify them biochemically into 3 subgroups,and describe the essential features of each member.

关键词： cholesterol metabolism neutral lipid biosynthesis protein acylation membrane phospholipid remodeling atherosclerosis diabetes obesity cancer nutrient sensing