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A DUAL-SURFACE DAMAGE MODEL AND EVALUATION FOR NATURAL SOILS WITHIN THE THERMOMECHANICAL FRAMEWORK

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Acta Mechanica Solida Sinica 2008年第1期21卷 85-94页

作者： xuan Guo Chenggang Zhao Dajun yuan Mengshu Wang Tunnel and Underground of Engineering Experienmental Research Center Beijing Jiaotong University Beijing 100044 China School of Civil Engineering ＆ Architecture Beijing Jiaotong University Beijing 100044 China

Naturally deposited or residual soils exhibit more complicated behavior than remolded clays. A dual-surface damage model for structured soils is developed based on the thermodynamics framework established in our first paper. The shift stresses and the transformation between the generalized dissipative stress space and actual stress space are established following a systematic procedure. The corresponding constitutive behavior of the proposed model is determined, which reflects the internal structural configuration and damage behavior for geomaterials. Four evolution variables κj^i（i=D, R;j=V, S） and the basic parameters λ, s, v and e0 are introduced to account for the progressive loss of internal structure for natural clays. A series of fully triaxial tests and isotropic compression tests are performed for structured and reconstituted samples of Beijing and Zhengzhou natural clays. The validation of the proposed model is examined by comparing the numerical results with the experimental data.

关键词： dual-surface damage model triaxial tests structured soils thermomechanical approach compressibility

A THERMOMECHANICAL DAMAGE APPROACH TO CONSTITUTIVE MODELS FOR RATE-INDEPENDENT DISSIPATIVE GEOMATERIALS

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Acta Mechanica Solida Sinica 2008年第1期21卷 73-84页

This paper builds the formulations of hyperplastic damage theory for rate-independent geomaterials to describe the bulk and the likely damage behavior of granular materials. Using 2 kinematic internal variables and the conjugates, dissipative and yield function can be reasonably introduced. A systematic constitutive presentation of 32 possible ways within the thermodynamical damage framework is presented, which entirely formulates the constitutive behavior through two scalar thermodynamic potentials. Combining the four common thermodynamical energy functions, two independent kinematic internal variables and the accordingly generalized stress are introduced to describe the damage behavior and structural rearrangement of the granules for any bulk deformation. A few Legendre transformations are used to establish the links between energy functions so that the complex incremental response of geomaterials can be entirely established from these four energy functions. The constitutive relations are built with the thermodynamics laws, which account for the important structural aspects of geomaterials. Some examples axe provided in the appendix to validate the applicability and implementation of the framework. This theory is based on previous work by Houlsby et al., and extends to the multi-mechanisms description. This framework paves a way in developing models for specific geomaterials with an examinable basis.

关键词： thermomechanical damage approach hyperplastic energy dissipation

Difference and clinical value of metabolites in plasma and feces of patients with alcohol-related liver cirrhosis

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World Journal of Gastroenterology 2023年第22期29卷 3534-3547页

作者： yi-Fan Xu Yan-Xu Hao Lei Ma Meng-Han Zhang xuan-xuan Niu Yan Li yuan-yuan Zhang Ting-Ting Liu Ming Han Xiao-Xue yuan Gang Wan Hui-Chun Xing Center of Liver Diseases Division 3 Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing Institute of Infectious Diseases Beijing Institute of Infectious DiseasesBeijing 100015China National Center for Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Statistic Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Center of Liver Diseases Division 3 Beijing Ditan HospitalPeking University Ditan Teaching HospitalBeijing 100015China

BACKGROUND Alterations in plasma and intestinal metabolites contribute to the pathogenesis and progression of alcohol-related liver cirrhosis(ALC).AIM To explore the common and different metabolites in the plasma and feces of patients with ALC and evaluate their clinical *** According to the inclusion and exclusion criteria,27 patients with ALC and 24 healthy controls(HCs)were selected,and plasma and feces samples were *** function,blood routine,and other indicators were detected with automatic biochemical and blood routine *** chromatography-mass spectrometry was used to detect the plasma and feces metabolites of the two groups and the metabolomics of plasma and ***,the correlation between metabolites and clinical features was *** More than 300 common metabolites were identified in the plasma and feces of patients with *** analysis showed that these metabolites are enriched in bile acid and amino acid metabolic *** to HCs,patients with ALC had a higher level of glycocholic acid(GCA)and taurocholic acid(TCA)in plasma and a lower level of deoxycholic acid(DCA)in the feces,while L-threonine,L-phenylalanine,and L-tyrosine increased simultaneously in plasma and ***,TCA,L-methionine,L-phenylalanine,and L-tyrosine in plasma were positively correlated with total bilirubin(TBil),prothrombin time(PT),and maddrey discriminant function score(MDF)and negatively correlated with cholinesterase(CHE)and albumin(ALB).The DCA in feces was negatively correlated with TBil,MDF,and PT and positively correlated with CHE and ***,we established a P/S BA ratio of plasma primary bile acid(GCA and TCA)to fecal secondary bile acid(DCA),which was relevant to TBil,PT,and MDF *** The enrichment of GCA,TCA,L-phenylalanine,L-tyrosine,and L-methionine in the plasma of patients with ALC and the reduction of DCA in feces were related to the severity of *** metabolites may be used as ind

关键词： Alcohol-related liver cirrhosis Plasma Feces Metabolites Deoxycholic acid Amino acids

CARs:a new approach for the treatment of autoimmune diseases

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Science China(Life Sciences) 2023年第4期66卷 711-728页

作者： Yeting Sun Yeshuang yuan Bo Zhang xuan Zhang Graduate School of Peking Union Medical College Department of RheumatologyBeijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineState Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Department of Rheumatology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineClinical Immunology CenterChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

The development of chimeric antigen receptor(CAR)-based therapeutic interventions represented a breakthrough in cancer *** the success of the CAR-T-cell strategy,this novel therapeutic approach has been applied to other diseases,including autoimmune *** CAR-T cells to deplete pathological immune cells(i.e.,B cells,autoreactive B or T cells,and accessory antigen-presenting cells(APCs))has resulted in favorable outcomes in diseases characterized by excessive autoantibody levels or hyperactive lymphocyte cell *** importance of immunosuppressive regulatory Tcells(Tregs)in restoring immune tolerance has been well established,and CAR-Tregs have shown promising therapeutic potential in treating autoimmune ***,prior experience from the cancer field has provided sufficient paradigms for understanding how to optimize the structure and function of CARs to improve their function,persistence,stability and *** this review,we describe the potential application of CAR-T cells and CAR-Tregs in the treatment of autoimmune diseases,and we summarize the currently available strategies of gene editing and synthetic biological tools that have improved the practical application of CAR-based therapies.

关键词： autoimmune diseases chimeric antigen receptor regulatory T cells cellular therapy

Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期 112-138页

作者： CHEN Junxu WANG yuan ZHAO Zhifang FAN Yunjiang LUO Xiaochuan yi Lu FENG Siqi YANG Liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Calcium-Mediated Mitochondrial Permeability Transition Involved in Hydrogen Peroxide-Induced Apoptosis in Tobacco Protoplasts

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Journal of Integrative Plant Biology 2006年第4期48卷 433-439页

作者： yuan Wang Jiu-Sheng Lin Gen-xuan Wang Key Laboratory of Arid Agroecology at Lanzhou University Ministry of Education Lanzhou 730000 China Department of Biochemisty and Plant Science Initiative George W. Beadle Center University of Nebraska-Lincoln Lincoln NE 68588 USA College of Life Sciences Zhejiang University Hangzhou 310027 China

In the present study, we focused on whether Intracellular free Ca^2＋（[Ca^2＋],） regulates the formation of mltochondrlal permeability transition pore （MPTP） In H2O2-induced apoptosis In tobacco protoplasts. It was shown that the decrease In mltochondrlal membrane potential （△ψm） preceded the appearance of H2O2-Induced apoptosls; pretreatment with the specific MPTP Inhibitor cyclosporine A, which also Inhibits Ca^2＋ cycling by the mitochondria, effectively retarded apoptosls and the decrease In △ψm. Apoptosls and decreased △ψm were exacerbated by CaCl2, whereas the plasma membrane voltage-dependent Ca^2＋ channel blocker lanthanum chloride （LaCl3） attentuated these responses. Chelation of extracellular Ca^2＋ with EGTA almost totally Inhibited apoptosls and the decrease In △ψmInduced by H2O2. The time-course of changes In [Ca^2＋]l In apoptosls was detected using the Ca^2＋ probe Fiuo-3 AM. These studies showed that [Ca^2＋]1 was Increased at the very early stage of H2O2-Induced apoptosls. The EGTA evidently Inhibited the Increase In [Ca^2＋]1 Induced by H=O=, whereas It was only partially Inhibited by LaCl3. The results suggest that H2O2 may elevate cytoplasmic free Ca^2＋ concentrations In tobacco protoplasts, which mainly results from the entry of extracellular Ca^2＋, to regulate mltochondrlal permeability transition. The signaling pathway of [Ca^2＋]1-medlated mltochondrlal permeability transition was associated with H2O2-Induced apoptosis In tobacco protoplaete.

关键词： apoptosis calcium hydrogen peroxide mitochondrial permeability transition pore programmed cell death tobacco protoplast.

Synthesis of Macroscopic Zr(C6H5PO3)2 Tubes

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Journal of Materials Science & Technology 2007年第5期23卷 717-720页

作者： yuan yuan Jianjun yi Chenglin MA Qinghong XU State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Petrochemical Research Institute PetroChina Company Ltd Beijing 100083 China

A new method of infiltration-diffusion is used to synthesize macroscopic α-Zr（C6H5PO3）2 （α-ZrBP） tube. Compared to the routine method, no HF was used and a fiberlike product with several millimeters in length was obtained. SEM （scanning electronic microscopy） result indicates that these fibers are tubes. The wall of the tubes is composed of the flake of α-ZrBP overlapped with each other. As we know, it is the first report on the synthesis of millimeter-scale supramolecular assembly of α-ZrBP.

关键词： α-ZrBP Infiltratlon-diffusion Tube Supramolecular self-assembly

A thermoelectric generator and water-cooling assisted high conversion efficiency polycrystalline silicon photovoltaic system

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Frontiers in Energy 2021年第2期15卷 358-366页

作者： Zekun LIU Shuang yuan yi yuan Guojian LI Qiang WANG Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory of Electromagnetic Processing of Materials of the Ministry of Education Northeastern UniversityShenyang 110819China

Solar energy has been increasing its share in the global energy structure. However, the thermal radiation brought by sunlight will attenuate the efficiency of solar cells. To reduce the temperature of the photovoltaic (PV) cell and improve the utilization efficiency of solar energy, a hybrid system composed of the PV cell, a thermoelectric generator (TEG), and a water-cooled plate (WCP) was manufactured. The WCP cannot only cool the PV cell, but also effectively generate additional electric energy with the TEG using the waste heat of the PV cell. The changes in the efficiency and power density of the hybrid system were obtained by real time monitoring. The thermal and electrical tests were performed at different irradiations and the same experiment temperature of 22°C. At a light intensity of 1000 W/m2, the steady-state temperature of the PV cell decreases from 86.8°C to 54.1°C, and the overall efficiency increases from 15.6% to 21.1%. At a light intensity of 800 W/m2, the steady-state temperature of the PV cell decreases from 70°C to 45.8°C, and the overall efficiency increases from 9.28% to 12.59%. At a light intensity of 400 W/m2, the steady-state temperature of the PV cell decreases from 38.5°C to 31.5°C, and the overall efficiency is approximately 3.8%, basically remain unchanged.

关键词： photovoltaic(PV) thermoelectric generator conversion efficiency hybrid energy systems water-cooled plate(WCP)

Preparation of a cationic azobenzene dye-montmorillonite intercalation compound and its photochemical behavior

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Journal of University of Science and Technology Beijing 2006年第3期13卷 281-286页

作者： Tao Wan yi yuan Wenqiong He College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 China

Montmorillonite/cationic azobenzene dye （GTL） intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure （J cluster） confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.

关键词： Na-montmorillonite azobenzene intercalation photoisomerization