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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 238-248页

作者： Ze-wei TAO Long-gui LI zhao-hua GENG Tao DANG Shan-jun ZHU Department of Cardiovascular Diseases Xinqiao Hospital Third Military Medical University Chongqing 40003 7 China

Therapeutically delivered mesenchymal stem cells (MSCs) improve ventricular remodeling. However,the mechanism underlying MSC cardiac remodeling has not been clearly determined. Congestive heart failure (CHF) was induced in rats by cauterization of the left ventricular free wall. MSCs were cultured from autologous bone marrow and injected into the border zone and the remote myocardium 5 d after injury. Ten weeks later,when compared with sham operation,CHF significantly increased nucleus mitotic index,capillary density,and expression of insulin-like growth factor 1,hepatocyte growth factor and vascular endothelial growth factor in the border zone (P<0.01) and decreased each of them in the remote myocardium (P<0.05 or P<0.01). MSC implantation in CHF dramatically elevated ex-pression of these growth factors in the remote myocardium and further elevated their expression in the border zone when compared with CHF without MSC addition (P<0.05 or P<0.01). This was paralleled by a higher nucleus mitotic index and a significantly increased capillary density both in the remote myocardium and in the border zone,and by a lower percentage of area of collagen and a higher percentage of area of myocardium in the border zone (P<0.05 or P<0.01),and cardiac remodeling markedly improved. Autologous MSC implantation promoted expression of growth factors in rat failing myocardium,which might enhance cardiomyogenesis and angiogenesis,and improved cardiac remodeling.

关键词： Mesenchymal stem cells Growth factor Myocardium Cardiac remodeling

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Rapidly counting atomic planes of ultra-thin MoSe2 nanosheets(1≤n≤4)on SiO2/Si substrate

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Rare Metals 2016年第8期35卷 632-636页

作者： Yi-Ping Wang Hui-Jun Zhou gui-hua zhao Tian-Long Xia Lei Wang Le Wang Li-Yuan Zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-electronic Functional Materialsand Micro-nano Devices Renmin University of China Department of Power and Electrical Engineering Northwest A&F UniversityYangling 712100ShaanxiChina

The optical, thermal and electrical properties of ultra-thin two-dimensional （2D） crystal materials are highly related to their thickness. Therefore, identifying the atomic planes of few-layer crystal materials rapidly is crucial to fundamental study. Here, a simple technique was demonstrated based on optical contrast for counting atomic planes （n） of few-layer MoSe2 on SiO2/Si substrates. It is found that the optical contrast of single-layer MoSe2 depends on light wavelength and thickness of SiO2 on Si substrate. The data calculated based on a Fresnel law-based model as well as atomic force microscopy （AFM） mea- surements fit well with the values measured by spectro- scopic ellipsometer. Furthermore, the calculated and measured contrasts were integral and plotted, which can be used to determine the MoSe2 atomic planes （1 ≤ n ≤ 4） accurately and rapidly.

关键词： Thickness identification Optical contrast MoSe2 Optical microscopy

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Finite-time stabilization of nonlocal Lipschitzian stochastic time-varying nonlinear systems with Markovian switching

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Science China(Information Sciences) 2022年第11期65卷 196-216页

作者： gui-hua zhao Shu-Jun LIU College of Science University of Shanghai for Science and Technology College of Mathematics Sichuan University

In this study, we investigate the stochastic finite-time stability theory and finite-time stabilization of stochastic time-varying nonlinear systems with Markovian switching in the sense of weak solutions. First,we present the stochastic finite-time stability theory under the framework of weak solutions: the existence of weak solutions and stochastic finite-time stability theorems for stochastic time-varying nonlinear systems with Markovian switching. Second, for a class of high-order stochastic nonlinear systems with Markovian switching, a finite-time stabilization controller is constructively designed, and the trivial weak solution of a closed-loop system is proven to be globally finite-time stable in probability. The effectiveness of the proposed finite-time control method is illustrated by a numerical example.

关键词： stochastic time-varying nonlinear systems Markovian switching weak solutions stochastic finite-time stability finite-time control

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Stochastic input-to-state stability of stochastic nonlinear systems with Markovain switching

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Stochastic input-to-state stability of stochastic nonlinear ...

Adaptive Finite-time Stabilization of Weak Solutions for a Class of Stochastic Nonlinear Systems with Parametric Uncertainty

第三十九届中国控制会议

作者： gui-hua zhao College of Science University of Shanghai for Science and Technology Department of Mathematics Jiangsu University of Science and Technology

The stochastic input-to-state stability（SISS） of stochastic nonlinear systems with Markovian switching（SNSwMS）is studied in this paper. Firstly, the notion of SISS for SNSwMS is introduced. And then SISS for SNSwMS is studied. Finally,by the method of changing the supply functions, the stability of cascaded stochastic input-to-state stable stochastic nonlinear subsystems with Markovian switching is investigated.

关键词： Stochastic Input-to-state Stability Stochastic Nonlinear Systems with Markovian Switching Cascaded Stochastic Input-to-state Stable Subsystems

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Adaptive Finite-time Stabilization of Weak Solutions for a C...

Improving performance of perovskite solar cells enabled by defects passivation and carrier transport dynamics regulation via organic additive

第37届中国控制会议

作者： gui-hua zhao Shu-Jun Liu College of Mathematics Southeast University Department of Mathematics Jiangsu University of Science and Technology College of Mathematics Sichuan University

In this paper,the finite-time stabilization for a class of stochastic nonlinear systems with parametric uncertainty is studied under the framework of weak solutions.A Lyapunov function is constructed by the method of adding a power integrator and a finite-time controller is constructively *** is proved that the closed-loop system has a global weak solution,states and control input of the closed-loop system reach the origin in a finite time and the parameter estimate is bounded with probability ***,a numerical simulation is given to illustrate the efficiency of the proposed design procedure.

关键词： Weak Solution Adaptive Control Finite-time Stability in Probability Stochastic Nonlinear Systems

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Chinese Chemical Letters 2025年第2期36卷 551-556页

作者： Rongjun zhao Tai Wu Yong hua Yude Wang Department of Physics Center for Optoelectronics Engineering ResearchYunnan University Yunnan Key Laboratory for Micro/Nano Materials&Technology International Joint Research Center for Optoelectronic and Energy MaterialsSchool of Materials and EnergyYunnan University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Defects at the grain boundaries(GBs) of perovskite film highly restrict both the efficiency and stability of perovskite solar cells(PSCs). Herein, organic small molecules of butanedioic acid(BA) and acetylenedicarboxylic acid(AA), containing two carbonyl(C=O) groups and different core-units, were incorporated into perovskite as additives for PSCs application. Thanks to the strong coordination interaction between C=O group and under-coordinated Pb2+, the additives can effectively passivate film defects and regulate the perovskite crystallization, yielding high-quality perovskite films with lower defect densities. More importantly, the additives can efficiently regulate the charge transport behaviors in PSCs. Benefiting from the defects passivation and the regulation of charge carrier dynamics, the BA and AA-treaded PSCs show the power conversion efficiencies of 21.52% and 20.50%, which are higher than that of the control device(19.41%). Besides, the optimal devices exhibit a remarkable enhanced long-term stability and moisture tolerance compared to the pristine devices. Furthermore, the transient absorption spectrum reveals the mechanism of enhanced photovoltaic performances, attributing to the improvement of charge transport capability at the perovskite/Spiro-OMeTAD interfaces. This work affords a promising strategy to improve the efficiency and stability of PSCs through regulating the charge-carrier dynamic process in perovskite film.

关键词： Additives Carrier dynamics Defects passivation Perovskite solar cells Stability

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe zhao Peng Liu Daoben hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences(RAD-X)Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China

The efficient separation of fission products,such as TcO_(4)^(-)and I^(-),holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis(bromomethyl)benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups(Cl@QPN),exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/(mg min)for ReO_(4)^(-)(a nonradioactive surrogate of TcO_(4)^(-))and 0.677 g/(mg min)for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO_(4)^(-)and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for^(99)TcO_(4)^(-).Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO_(4)^(-),respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

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Leaching of WO_(3)from sulfuric acid converted product of scheelite in NH_(3)·H_(2)O−NH_(4)HCO_(3)solution

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Transactions of Nonferrous Metals Society of China 2025年第1期35卷 326-337页

作者： Lei-ting SHEN Yu LIU Juan-lang GUO Qiu-sheng ZHOU Tian-gui QI Zhi-hong PENG gui-hua LIU Xiao-bin LI School of Metallurgy and Environment Central South UniversityChangsha 410083China

The leaching of sulfuric acid converted product of scheelite in NH_(3)·H_(2)O−NH_(4)HCO_(3)solution was systemically studied to improve sulfuric acid conversion−ammonium salts leaching technology route for ammonium paratungstate *** results showed that the WO_(3)leaching efficiency was about 99%under optimal conditions of 350 r/min,liquid-to-solid ratio of 3 mL/g,1 mol/L NH_(4)HCO_(3),4 mol/L NH_(3)·H_(2)O,25℃,and 15 *** the leaching,CaSO_(4)almost had no change and was still in a banding or rod-like shape in short leaching time,while conglobate CaCO_(3)was gradually formed on the CaSO_(4)surface.A secondary reaction might occur between CaSO_(4)and WO_(4)^(2−),which could be restrained by a certain amount of CO_(3)^(2−)in the *** was no CaCO_(3)phase determined by XRD in leaching residue of converted product for scheelite concentrate under optimal conditions,which was different from that for synthetic *** leaching process could be explained by neutralization reaction of H_(2)WO_(4)and solid transformation of CaSO_(4)in NH_(3)·H_(2)O−NH_(4)HCO_(3)solution.

关键词： tungstic acid calcium sulfate leaching mechanism calcium carbonate ammonium tungstate

Visible-light-induced ring-opening cross-coupling of cycloalcohols with vinylazaarenes and enones via β-C-C scission enabled by proton-coupled electron transfer

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Chinese Chemical Letters 2025年第2期36卷 400-405页

作者： Qinghong Zhang Qiao zhao Xiaodi Wu Li Wang Kairui Shen Yuchen hua Cheng Gao Yu Zhang Mei Peng Kai zhao Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech University College of Chemical Engineering Nanjing Forestry University College of Pharmacy Hengyang Medical SchoolUniversity of South China School of Chemistry and Chemical Engineering Henan Normal University

Pyridyl-based ketones and 1,6-diketones are both attractive and invaluable scaffolds which play pivotal roles in the construction and structural modification of a plethora of synthetically paramount natural products, pharmaceuticals, organic materials and fine chemicals. In this context, we herein demonstrate an unprecedented, robust and generally applicable synthetically strategy to deliver these two crucial ketone frameworks via visible-light-induced ring-opening coupling reactions of cycloalcohols with vinylazaarenes and enones, respectively. A plausible mechanism involves the selective β-C-C bond cleavage of cycloalcohols enabled by proton-coupled electron transfer and ensuing Giese-type addition followed by single electron reduction and protonation. The synthetic methodology exhibits broad substrate scope,excellent functional group compatibility as well as operational simplicity and environmental friendliness.

关键词： 1,6-Diketone C-C Bond cleavage Proton-coupled electron transfer Pyridyl-based ketone Ring-opening coupling

Detection and interpretation of the time-varying seasonal signals in China with multi-geodetic measurements

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Geodesy and Geodynamics 2025年第1期16卷 42-54页

作者： Liansheng Deng Yugang Xiao Qusen Chen Wei Peng zhao Li hua Chen Zhiwen Wu School of Electrical and Electronic Information Engineering Hubei Polytechnic University Hubei Luojia Laboratory GNSS Research Center Wuhan University Changjiang Spatial Information Technology Engineering Co. Ltd. Key Laboratory of Spatial Data Mining & Information Sharing of the Ministry of Education Fuzhou University School of Geodesy and Geomatics Wuhan University The First Surveying and Mapping Institute of Hunan Province

The time-varying periodic variations in Global Navigation Satellite System(GNSS) stations affect the reliable time series analysis and appropriate geophysical interpretation. In this study, we apply the singular spectrum analysis(SSA) method to characterize and interpret the periodic patterns of GNSS deformations in China using multiple geodetic datasets. These include 23-year observations from the Crustal Movement Observation Network of China(CMONOC), displacements inferred from the Gravity Recovery and Climate Experiment(GRACE), and loadings derived from Geophysical models(GM). The results reveal that all CMONOC time series exhibit seasonal signals characterized by amplitude and phase modulations, and the SSA method outperforms the traditional least squares fitting(LSF) method in extracting and interpreting the time-varying seasonal signals from the original time series. The decrease in the root mean square(RMS) correlates well with the annual cycle variance estimated by the SSA method, and the average reduction in noise amplitudes is nearly twice as much for SSA filtered results compared with those from the LSF method. With SSA analysis,the time-varying seasonal signals for all the selected stations can be identified in the reconstructed components corresponding to the first ten eigenvalues. Moreover, both RMS reduction and correlation analysis imply the advantages of GRACE solutions in explaining the GNSS periodic variations,and the geophysical effects can account for 71% of the GNSS annual amplitudes, and the average RMS reduction is 15%. The SSA method has proved to be useful for investigating the GNSS timevarying seasonal signals. It could be applicable as an auxiliary tool in the improvement of nonlinear variations investigations.

关键词： GNSS coordinate time series Singular spectrum analysis Time-varying seasonal signals Loading effects GRACE