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Communications on Applied Mathematics and Computation 2021年第1期3卷 123-135页

作者： xiao-xia Guo hong-xiao Wu School of Mathematical Science Ocean University of ChinaQingdao 266100Shandong ProvinceChina

In this paper,we study the nonlinear matrix equation X-A^(H)X^(-1)A=Q,where A,Q∈C^(n×n),Q is a Hermitian positive definite matrix and X∈C^(n×n)is an unknown *** prove that the equation always has a unique Hermitian positive definite *** present two structure-preserving-doubling like algorithms to find the Hermitian positive definite solution of the equation,and the convergence theories are ***,we show the effectiveness of the algorithms by numerical experiments.

关键词： Positive definite solution Structure-preserving-doubling like algorithm Convergence Numerical experiment

Advance in the understanding of vasovagal syncope in children and adolescents

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World Journal of Pediatrics 2021年第1期17卷 58-62页

作者： hong-xia Li Lu Gao Yue Yuan Department of Cardiology National Center for Children's HealthBeijing Children's HospitalCapital Medical UniversityBeijingChina

Background Vasovagal syncope(VVS)accounts for 60-80% of cases of neurally mediated *** results from acute orthostatic intolerance and recurrent syncopal attacks,which can seriously affect an individual's quality of *** addition,some children even experience trauma during ***,it is particularly important to clarify the pathogenesis of *** aim of our study is to reveal the latest research progress of *** sources Literature that involved the pathogenesis of VVS were selected from Cochrane Library(1990-2019),EMBASE(1991-2019)and PubMed(1968-2019)*** Hypovolemia,autonomic dysfunction,vasomotor dysfunction,baroreceptor reflex abnormalities,endothelial dys-function,serotonin surges,and gut microbiota were involved in the underlying mechanism of *** VVS is not always a benign *** aspects were involved in its ***-Jarish reflex,dysfunction of the autonomic nervous system,genetic factors and so on played important roles in VVS;however,the mecha-nism remains unclear.

关键词： Autonomic nervous system Bezold-Jarish reflex Children Genetic pathogenesis Vasovagal syncope

STUDY OF THE FLOWTHROUGH NON-SUBMERGED VEGETATION

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Journal of Hydrodynamics 2005年第4期17卷 498-502页

作者： NEHAL Laounia YAN Zhong-min xia Ji-hong College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

Vegetation is an important feature of many rivers. Vegetation along rivers produces high resistance to flow and, as a result, has a large impact on water levels in rivers and lakes. The effects of instream-unsubmerged vegetation （such as the reed-similar Kalmus） on flow resistance and velocity distributions is studied in the paper. Artificial vegetation is used in the experimental study to simulate the Acorus Calmus L. As shown in experimental tests the resistance depends strongly on vegetation density and the Manning resistance coefficient varies with the depth of flow. A simplified model based on concepts of drag is developed to evaluate the roughness coefficient （Manning＇s n） for non submerged vegetation. In vegetated channels the overall flow resistance is influenced significantly by the distribution pattern of the vegetated beds. Within vegetation, vertical variation in velocity is different from that in the non vegetated bed, which reflects the variation in vegetation density. Vertical turbulent transport of momentum is negligible as demonstrated by experiments.

关键词： open channel flow non-submerged vegeta-tion vegetation density flow resistance velocity distribution

Specific Heat of the Spin-1/2 Antiferromagnetic Heisenberg Chain

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Chinese Physics Letters 2001年第9期18卷 1261-1263页

作者： YUN Guo-hong LIANG Xi-xia Department of Physics Inner Mongolia UniversityHohhot 010021

A simple analytic theory of thermodynamics at finite temperature for the spin-1/2 antiferromagnetic Heisenberg chain is proposed based on the picture of the particle-hole pair excitations. The dispersion relation of the particle-hole pairs is derived in the formulation of thermodynamic Bethe ansatz provided that the particles and holes have the same energy and they are excited as normalmodes. It is shown that the behaviour of the specific heat is in excellent agreement with the numerical and experimental results.

关键词： Heisenberg ferromagnetic thermodynamics

Quasi-Z Source Inverter Control of PV Grid-Connected Based on Fuzzy PCI

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Journal of Electronic Science and Technology 2021年第3期19卷 274-286页

作者： Tao Hou Chen-Yang Zhang hong-xia Niu School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070 Automatic Control Research Institute Lanzhou Jiaotong UniversityLanzhou 730070

The photovoltaic grid-connected inverter is an important interface between the photovoltaic power generation system and power *** high-quality operation is directly related to the output power quality of the power *** order to further optimize the control effect of the quasi-Z source grid-connected photovoltaic inverter,a fuzzy proportional complex integral control(PCI)method is proposed for the current internal loop *** method can eliminate the steady-state error,and has the characteristic of zero steady-state error adjustment for the AC disturbance signal of a specific *** inductance-capacitance-inductance(LCL)filter is adopted in the grid-connected circuit,and the feedback capacitive current is taken as the control variable of the inner loop to form the active damping control method,which can not only effectively suppress the resonance of the LCL circuit,but also significantly inhibit the high-order harmonics in the grid-connected ***,a system simulation model is built in MATLAB/Simulink to verify the superiority and effectiveness of the proposed method.

关键词： Frequency of harmonic distortion fuzzy proportional complex integral inductance-capacitance-inductance(LCL)filtering circuit photovoltaic grid-connection quasi-Z source inverter

Hankel Operators on Bergman Spaces of Annulus Induced by Regular Weights

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Acta Mathematica Sinica,English Series 2021年第5期37卷 775-804页

作者： Li hong YANG xiao Feng WANG Jin xia School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006P.R.China

This paper is devoted to studying Bergman spaces A_(ω_(1,2))^(p)(M)(1 详细信息

This paper is devoted to studying Bergman spaces A_(ω_(1,2))^(p)(M)(1

关键词： Hankel operators regular-weight annulus Bergman spaces

Pitch control strategy before the rated power for variable speed wind turbines at high altitudes

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Journal of Hydrodynamics 2019年第2期31卷 379-388页

作者： Ming-wei Ge Wei-ming Ke hong-xia Chen School of Renewable Energy North China Electric Power UniversityBeijingl 02206China School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The wind turbines in the world's highest wind farm with an altitude of over 4 000 m in Naqu county of China were put into operation in *** with the wind turbines at lower altitudes,the rated wind speed of these wind turbines are much larger,and the corresponding tip-speed ratio at the rated power reduces significantly due to the lower air ***,the power coefficient at the point of the rated power is decreased to a rather low *** improve the performance of the wind turbines at very high altitudes,this paper proposes a new pitch control strategy for variable speed wind turbines at the constant-speed phase,especially at the rated-speed phase before the rated power is *** is shown that the new pitch control strategy works very well for the wind farms at very high altitude and with low air density,with the catch of the wind energy enhaneed and the aerodynamic loads significantly reduced.

关键词： Wind turbine pitch control strategy high altitudes

Surface reaction of Bacillus cereus biomass and its biosorption for lead and copper ions

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Journal of Environmental Sciences 2007年第4期19卷 403-408页

作者： PAN Jian-hua LIU Rui-xia TANG hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

In this study, the surface chemical functional groups of Bacillus cereus biomass were identified by Fourier transform infrared （FTIR） analytical technique. It had been shown that the B. cereus cells mainly contained carboxyl, hydroxyl, phosphate, amino and amide functional groups. The potentiometric titration was conducted to explain the surface acid-base properties of aqueous B. cereus biomass. The computer program FITEQL 4.0 was used to perform the model calculations. The optimization results indicated that three sitesthree pKas model, which assumed the cell surface to have three distinct types of surface organic functional groups based on the IR analysis results, simulated the experimental results very well. Moreover, batch adsorption experiments were performed to investigate biosorption behavior of Cu（Ⅱ） and Pb（Ⅱ） ions onto the biomass. Obviously, the adsorption equilibrium data for the two ions were reasonably described by typical Langmuir isotherm.

关键词： Bacillus cereus biosorption Fourier transform infrared (FTIR) acid-base characteristic heavy metals

Derivation of a second-order model for Reynolds stress using renormalization group analysis and the two-scale expansion technique

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Acta Mechanica Sinica 2011年第5期27卷 649-659页

作者： xiao-hong Wang Zheng-Feng Liu xiao-xia Lu Department of Thermal Science and Energy Engineering University of Science and Technology of China230026 Hefei China

With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic *** a low-order two-scale expansion,applying the mode coupling approximation in the Yakhot-Orszag renormalization group method to analyze the fluctuating field,the Reynolds-average terms in the Reynolds stress transport equation,such as the convective term,the pressure-gradient-velocity correlation term and the dissipation term,are *** numerical examples：turbulent flow past a backward-facing step and the fully developed flow in a rotating channel,are presented for testing the efficiency of the proposed second-order *** these two numerical examples,the proposed model performs as well as the Gibson-Launder （GL） model,giving better prediction than the standard k-ε model,especially in the abilities to calculate the secondary flow in the backward-facing step flow and to capture the asymmetric turbulent structure caused by frame rotation.

关键词： Turbulent modeling Renormalization group Two-scale expansion Reynolds stress transport equation Second-order model

Visualization of the protective role of estrogen against female liver fibrosis via an ER viscosity NIR fluorescent probe

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Science China Chemistry 2025年第1期 360-368页

作者： Zheng Liu Changyu Zhang Zipeng Li Wanying Ma Jia Liu xiang xia Ning Xu Wen Sun Jianjun Du Jiangli Fan xiaojun Peng State Key Laboratory of Fine Chemicals Dalian University of Technology Ningbo Institute of Dalian University of Technology

Endoplasmic reticulum(ER) viscosity has emerged as a new potential biomarker for hepatic fibrosis(HF). Herein, we report the first ER-targeting viscosity-responsive near-infrared(NIR) fluorescent probe HBT-PP for investigations of HF *** twisted intramolecular charge transfer(TICT) and the excited state intramolecular proton transfer(ESIPT) are combined to endow HBT-PP with the selective response towards viscosity(～62-fold) and a super large stokes shift(～320 nm). HBT-PP mainly targets organelle ER and is able to image the drug-or alcohol-induced viscosity elevation in living cells. Significantly,HBT-PP was successfully applied to visualize the gender difference in HF and the protective role of estrogen in restraining HF progression. Of note, after 10 min of stain with HBT-PP, HF lesions showed a stage-based response, indicating the potential of this probe in fast and early diagnosis of HF. These results clearly demonstrated the promising application of HBT-PP as a new tool for exploring ER viscosity-involved physiological and pathological processes.

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