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Science China(Information Sciences) 2025年第2期68卷 200-215页

作者： Yunxiang MA tong.zhou Department of Automation Tsinghua University Department of Automation and BNRist Tsinghua University

This paper investigates the identifiability of structured systems with a matrix fraction description and attacks practical difficulties in estimating parameters under finite frequency responses. The numerator and denominator polynomial matrices depend affinely on system parameters, which can represent a broad range of systems, especially circuits and mechanical systems. Except for assuming that the denominator matrix is invertible, no further assumptions are adopted. A criterion is provided for validating this assumption utilizing graph theories and matroids. A sufficient and necessary criterion for global identifiability based on the rank of a numerical matrix is given and can be recursively verified with each frequency point,which is computationally attractive for large-scale systems. For an identifiable system, an ellipsoid approximation is obtained for the set of parameters whose corresponding system frequency responses deviate within a specific range from those of the system at a specific parameter value. Using this approximation, explicit expressions for absolute and relative sloppiness have been derived, which can be used to quantify the difficulty of identifying system parameters. Comparisons with the well-known Fisher information matrix have also been performed through a mechanical system, revealing significant differences in quantifying parameter estimation hardness.

关键词： identifiability sloppiness structured system matrix fraction graph theory matroid

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Classifying extended,localized and critical states in quasiperiodic lattices via unsupervised learning

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Chinese Physics B 2025年第1期34卷 422-427页

作者： Bohan Zheng Siyu Zhu Xingping zhou tong Liu School of Computer Science and Technology School of SoftwareNanjing University of Posts and TelecommunicationsNanjing 210023China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Department of Applied Physics School of ScienceNanjing University of Posts and TelecommunicationsNanjing 210003China

Classification of quantum phases is one of the most important areas of research in condensed matter *** this work,we obtain the phase diagram of one-dimensional quasiperiodic models via unsupervised ***,we choose two advanced unsupervised learning algorithms,namely,density-based spatial clustering of applications with noise(DBSCAN)and ordering points to identify the clustering structure(OPTICS),to explore the distinct phases of the Aubry–André–Harper model and the quasiperiodic p-wave *** unsupervised learning results match well with those obtained through traditional numerical ***,we assess similarity across different algorithms and find that the highest degree of similarity between the results of unsupervised learning algorithms and those of traditional algorithms exceeds 98%.Our work sheds light on applications of unsupervised learning for phase classification.

关键词： quantum phase quasiperiodic machine learning

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Nickel-copper alloying arrays realizing efficient co-electrosynthesis of adipic acid and hydrogen

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Journal of Energy Chemistry 2025年第02期101卷 7-15页

作者： Xuhui Ren Qianyu Zhang Yun tong Guorong zhou Cong Lin Yanying Zhao Pengzuo Chen School of Chemistry and Chemical Engineering Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province Zhejiang Sci-Tech University

Constructing electrocatalytic overall reaction technology to couple the electrosynthesis of adipic acid with energy-saving hydrogen production is of significant for sustainable energy ***,the development of highly-active bifunctional electrocatalysts remains a ***,3D hierarchical nickel-copper alloying arrays with dendritic morphology are manufactured by a simple electrodeposition process,standing for the excellent bifunctional electrocatalyst towards the co-production of adipic acid and H2from cyclohexanone and *** membrane-free flow electrolyzer of Cu0.81Ni0.19/NF shows the superior electrooxidation performance of ketone-alcohol（KA） oil with high faradaic efficiencies of over 90% for adipic acid and H2,robust stability over 200 h as well as a high yield of 0.6 mmol h-1for adipic acid at 100 mA ***-situ spectroscopy indicates the Cu0.81Ni0.19alloy contributes to forming more active NiOOH species to involve in the conversion of cyclohexanone to adipic acid,while the proposed reaction pathway undergoes the 2-hydroxycyclohexanone and 2,7-oxepanedione ***,the theoretical calculations confirm that the optimal electronic interaction,boosted reaction kinetics as well as improved adsorption free energy of reaction intermediates,synergistically endows Cu0.81Ni0.19alloy with superior bifunctional performance.

关键词： Adipic acid Cu0.81Ni0.19 alloy Cyclohexanone oxidation reaction Hydrogen evolution reaction Hydrogen fuel

Interfacial Zn^(2+)-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao zhou Xiongbin Luo Hang Li Shan Guo Zhuang tong Xiaotao zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional MaterialsHunan Institute of Science and TechnologyYueyang 414006HunanChina School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South UniversityChangsha 410083HunanChina College of Materials and Metallurgy Guizhou UniversityGuiyang 550000GuizhouChina National Energy Metal Resources and New Materials Key Laboratory Central South UniversityChangsha 410083HunanChina

Aqueous zinc-ion batteries (AZIBs) are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc (Zn) deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn^(2+)-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups (such as hydroxyl,carboxyl,etc.) have the potential to significantly optimize the solvation structure of Zn^(2+)and regulate the interfacial electric double layer (EDL).By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn (H-Zn) anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH_(4)V_(4)O^(10)(NVO) full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A g^(-1).This study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Zn^(2+)-solvation structure Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： tongyue Li Ziliang Xie Wenjiao zhou Huan tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

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tongmai Hypoglycemic Capsule Attenuates Myocardial Oxidative Stress and Fibrosis in the Development of Diabetic Cardiomyopathy in Rats

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CHINESE JOURNAL OF INTEGRATIVE MEDICINE 2025年第3期31卷 251-260页

作者： Zeng, Jie-qiong zhou, Hui-fen Du, Hai-xia Wu, Yu-jia Mao, Qian-ping Yin, Jun-jun Wan, Hai-tong Yang, Jie-hong Zhejiang Chinese Med Univ Coll Basic Med Sci Hangzhou 310051 Peoples R China Zhejiang Chinese Med Univ Coll Life Sci Hangzhou 310051 Peoples R China

Objective: To investigate the effect of tongmai Hypoglycemic Capsule (THC) on myocardium injury in diabetic cardiomyopathy (DCM) rats. Methods: A total of 24 Sprague Dawley rats were fed for 4 weeks with high-fat and high-sugar food and then injected with streptozotocin intraperitoneally for the establishment of the DCM model. In addition, 6 rats with normal diets were used as the control group. After modeling, 24 DCM rats were randomly divided into the model, L-THC, M-THC, and H-THC groups by computer generated random numbers, and 0, 0.16, 0.32, 0.64 g/kg of THC were adopted respectively by gavage, with 6 rats in each group. After 12 weeks of THC administration, echocardiography, histopathological staining, biochemical analysis, and Western blot were used to detect the changes in myocardial structure, oxidative stress (OS), biochemical indexes, protein expressions of myocardial fibrosis, and nuclear factor erythroid 2-related faactor 2 (Nrf2) element, respectively. Results: Treatment with THC significantly decreased cardiac markers such as creatine kinase, lactate dehydrogenase, and creatine kinase-MB, etc., (P<0.01);enhanced cardiac function indicators including heart rate, ejection fraction, cardiac output, interventricular septal thickness at diastole, and others (P<0.05 or P<0.01);decreased levels of biochemical indicators such as fasting blood glucose, total cholesterol, triglycerides, low-density lipoprotein cholesterol, aspartate transaminase, (P<0.05 or P<0.01);and decreased the levels of myocardial fibrosis markers alpha-smooth muscle actin (alpha-SMA), and collagen I (Col-1) protein (P<0.01), improved myocardial morphology and the status of myocardial interstitial fibrosis. THC significantly reduced malondialdehyde levels in model rats (P<0.01), increased levels of catalase, superoxide dismutase, and glutathione (P<0.01), and significantly increased the expression of Nrf2, NAD(P)H:quinone oxidoreductase 1, heme oxygenase-1, and superoxide dismutase 2 prot

关键词： tongmai Hypoglycemic Capsule oxidative stress Nrf2 element myocardial fibrosis diabetic cardiomyopathy

Prox1a promotes liver growth and differentiation by repressing cdx1b expression and intestinal fate transition in zebrafish

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Journal of Genetics and Genomics 2025年第1期52卷 66-77页

作者： Yingying Hu zhou Luo Meiwen Wang Zekai Wu Yunxing Liu Zhenchao Cheng Yuhan Sun Jing-Wei Xiong Xiangjun tong Zuoyan Zhu Bo Zhang Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education College of Life SciencesPeking UniversityBeijing 100871China Laboratory of Chemical Genomics School of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen University TownShenzhenGuangdong 518055China College of Biological Sciences China Agricultural UniversityBeijing 100193China Institute of Molecular Medicine College of Future TechnologyPeking UniversityBeijing 100871China

The liver is a key endoderm-derived multifunctional organ within the digestive *** homeobox 1(Prox1)is an essential transcription factor for liver development,but its specific function is not well ***,we show that hepatic development,including the formation of intrahepatic biliary and vascular networks,is severely disrupted in prox1a mutant *** find that Prox1a is essential for liver growth and proper differentiation but not required for early hepatic cell fate ***,prox1a depletion leads to ectopic initiation of a Cdx1b-mediated intestinal program and the formation of intestinal lumen-like structures within the *** knockdown of cdx1b alleviates liver defects in the prox1a mutant ***,chromatin immunoprecipitation analysis reveals that Prox1a binds directly to the promoter region of cdx1b,thereby repressing its ***,our findings indicate that Prox1a is required to promote and protect hepatic development by repression of Cdx1b-mediated intestinal cell fate in zebrafish.

关键词： Zebrafish Liver development prox1a cdx1b Cell fate transition

Balancing charge carrier density and exciton recombination in defective g-C3N4 for efficient photocatalytic hydrogen evolution

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Progress in Natural Science:Materials International 2025年第01期 238-244页

作者： Peng Wu Tao zhou Zhongqiu tong Fengshuo Xi Jijun Lu Xiufeng Li Wenhui Ma Shaoyuan Li Xingwei Yang Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology School of Engineering Yunnan University

Graphitic carbon nitride（g-C3N4） is a promising material for photocatalytic hydrogen production owing to its tunable band structure and high charge carrier density, however, it displays a high carrier recombination *** engineering can solve this problem by providing active sites within g-C3N4to accelerate the separation of photogenerated electrons and holes and enhance its solar light absorption. Previous studies have implied that there exists a defect concentration threshold for obtaining the maximum photocatalytic hydrogen production performance, but the underlying mechanism remains unclear. In this study, the relationship between charge carrier density and exciton recombination was investigated to address this issue. A series of g-C3N4photocatalysts with different tri-coordinate nitrogen（N3C） vacancy concentrations were synthesized using in-situ coprecipitation polymerization. The catalytic performance is related to the vacancy concentration, higher vacancy concentration will lead to higher carrier separation efficiency and carrier density of g-C3N4, as well as better photocatalytic hydrogen production performance. However, when excessive vacancies act as recombination centers, the charge carrier recombination rate is increased, which will also adversely affect the photocatalytic hydrogen production performance.

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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang Ying Zhu Pu Chen tong.zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long zhou Wei-Jin Jiang Ji Yu Mao-Jun Yao Yun-tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components