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SUPERCRITICAL CARBON DIOXIDE ASSISTED SYNTHESIS OF AMPHIPHIliC GRAFT COPOLYMERS BASED ON POLY(STYRENE-CO-MALEIC ANHYDRIDE) WITH METHOXYL POLY(ETHYLENE GLYCOL) SIDE CHAINS

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Chinese Journal of Polymer Science 2012年第2期30卷 173-180页

作者： jian-hua Wang li-ping Zhu Zhuan yi jian-hua li You-yi Xu Bao-ku Zhu MOE Key Laboratory of Macromolecule Synthesis and Functionalization MOE Engineering Research Center of Membrane and Water Treatment TechnologyDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Supercritical carbon dioxide （scCO2） was used as a reaction medium in synthesizing amphiphilic graft copolymers composed of poly（styrene-co-maleic anhydride）（SMA） backbones and methoxyl poly（ethylene glycol）（MPEG） side chains via esterification. The synthesized copolymers were characterized by Fourier transform infrared spectroscopy （FTIR）, gel permeation chromatography （GPC）, IH-NMR, thermo-gravimetric analysis （TGA） and differential scanning calorimetric analysis （DSC）. The gelation phenomenon was suppressed effectively by tuning reaction conditions. The influences of scCO2 temperature and pressure on the conversion of anhydride were investigated. It was found that the highest conversion ratio occurred at 80~C under a constant pressure of 14 MPa or 26 MPa. With the increase of scCO2 pressure, the conversion ratio increased first, and then leveled off. The conversion ratio of anhydride could be controlled by regulating the reaction conditions. It was also revealed that using low molecular weight MPEG brought a high conversion ratio of anhydride.

关键词： Supercritical carbon dioxide Poly(styrene-co-maleic anhydride) Poly(ethylene glycol) Amphiphilic graftcopolymer.

Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun jian li Rucong Yu Nina li yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale *** we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble *** to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation *** the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport *** a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present *** the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the *** summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

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STT焊接在工业锅炉行业的应用浅析

工业锅炉 2016年第5期 39-41页

作者：张羽潘建峰李翊坤徐展杭州富尔顿热能设备有限公司浙江杭州310018

STT(Surface Tension Transfer,表面张力熔滴过渡)焊接技术已在管道及薄板焊接等领域得到良好应用。为了提高锅炉焊接过程中的焊接速度并降低对焊工的技术要求,采用STT焊机进行了工业锅炉产品的焊接试验。其焊接速度是原有氩弧焊的3倍以... 详细信息

STT(Surface Tension Transfer,表面张力熔滴过渡)焊接技术已在管道及薄板焊接等领域得到良好应用。为了提高锅炉焊接过程中的焊接速度并降低对焊工的技术要求,采用STT焊机进行了工业锅炉产品的焊接试验。其焊接速度是原有氩弧焊的3倍以上,非熟练焊工也可掌握技法并保证焊接质量。

关键词： STT焊接工业锅炉:应用

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呼吸机常用脱机方法及其临床应用

实用医技杂志 2003年第5期10卷 482-483页

作者：左建云尹立云穆信利济南市中心医院山东济南250013

呼吸机脱机是指逐渐降低机械通气支持水平,逐步恢复患者自主呼吸,最终脱离呼吸机的过程[1].过早脱机会加重呼吸负担,导致呼吸肌疲劳及再次出现呼吸衰竭,而延迟脱机可能导致呼吸机依赖和产生多种并发症.

关键词：呼吸机脱机方法临床应用并发症同步间歇指令通气 PSV CPAP

Implementation of a Conservative Two-step Shape-Preserving Advection Scheme on a Spherical Icosahedral Hexagonal Geodesic Grid

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Advances in Atmospheric Sciences 2017年第3期34卷 411-427页

作者： yi ZHANG Rucong YU jian li State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China

An Eulerian flux-form advection scheme, called the Two-step Shape-Preserving Advection Scheme （TSPAS）, was generalized and implemented on a spherical icosahedral hexagonal grid （also referred to as a geodesic grid） to solve the transport equation. The C grid discretization was used for the spatial discretization. To implement TSPAS on an unstructured grid, the original finite-difference scheme was further generalized. The two-step integration utilizes a combination of two separate schemes （a low-order monotone scheme and a high-order scheme that typically cannot ensure monotonicity） to calculate the fluxes at the cell walls （one scheme corresponds to one cell wall）. The choice between these two schemes for each edge depends on a pre-updated scalar value using slightly increased fluxes. After the determination of an appropriate scheme, the final integration at a target cell is achieved by summing the fluxes that are computed by the different schemes. The conservative and shape-preserving properties of the generalized scheme are demonstrated. Numerical experiments are conducted at several horizontal resolutions. TSPAS is compared with the Flux Corrected Transport （FCT） approach to demonstrate the differences between the two methods, and several transport tests are performed to examine the accuracy, efficiency and robustness of the two schemes.

关键词： transport equation advection scheme spherical icosahedral hexagonal geodesic grid shape preservation numerical test

Evolving understanding of autoimmune mechanisms and new therapeutic strategies of autoimmune disorders

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SIGNAL TRANSDUCTION AND TARGETED THERAPY 2024年第1期9卷 263页

作者： Song, yi li, jian Wu, Yuzhang Third Mil Med Univ Army Med Univ Inst Immunol PLA Chongqing Peoples R China Chongqing Int Inst Immunol Chongqing Peoples R China

Autoimmune disorders are characterized by aberrant T cell and B cell reactivity to the body's own components, resulting in tissue destruction and organ dysfunction. Autoimmune diseases affect a wide range of people in many parts of the world and have become one of the major concerns in public health. In recent years, there have been substantial progress in our understanding of the epidemiology, risk factors, pathogenesis and mechanisms of autoimmune diseases. Current approved therapeutic interventions for autoimmune diseases are mainly non-specific immunomodulators and may cause broad immunosuppression that leads to serious adverse effects. To overcome the limitations of immunosuppressive drugs in treating autoimmune diseases, precise and target-specific strategies are urgently needed. To date, significant advances have been made in our understanding of the mechanisms of immune tolerance, offering a new avenue for developing antigen-specific immunotherapies for autoimmune diseases. These antigen-specific approaches have shown great potential in various preclinical animal models and recently been evaluated in clinical trials. This review describes the common epidemiology, clinical manifestation and mechanisms of autoimmune diseases, with a focus on typical autoimmune diseases including multiple sclerosis, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, and sj & ouml;gren's syndrome. We discuss the current therapeutics developed in this field, highlight the recent advances in the use of nanomaterials and mRNA vaccine techniques to induce antigen-specific immune tolerance.

关键词： autoimmune epidemiology therapeutic

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致密砂岩油气储层岩石变形理论与应力敏感性

天然气地球科学 2004年第5期15卷 482-486页

作者：张浩康毅力陈一健李前贵游利军何健西南石油学院油气藏地质及开发工程国家重点实验室四川成都610500

在致密砂岩油气藏开发过程中,由于孔隙压力下降,导致有效应力增加,储层岩石孔隙、裂缝发生形变和渗透率受到影响。从岩石力学角度分析了与致密砂岩形变相关的理论及形变影响因素,并通过应力敏感性实验研究了有效应力改变条件下的致密砂... 详细信息

在致密砂岩油气藏开发过程中,由于孔隙压力下降,导致有效应力增加,储层岩石孔隙、裂缝发生形变和渗透率受到影响。从岩石力学角度分析了与致密砂岩形变相关的理论及形变影响因素,并通过应力敏感性实验研究了有效应力改变条件下的致密砂岩岩样孔隙度、渗透率变化规律。结果表明:致密砂岩形变主要为应力变化时孔隙体积及裂缝宽度的变化,认为致密砂岩油气藏开发过程中储层岩石的形变一般属于弹性形变或者弹-塑性形变。形变取决于岩石碎屑颗粒硬度、颗粒之间接触关系、胶结情况、岩石中裂缝发育特征等。有效应力增加在压缩致密砂岩孔隙、喉道体积以及裂缝宽度的同时,也使得其渗透率大幅度降低,造成严重的储层损害。

关键词：致密砂岩油气储层岩石力学形变应力敏感性储层损害

Modeling and control of a small solar fuel cell hybrid energy system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 734-740页

作者： li Wei ZHU Xin-jian CAO Guang-yi Fuel Cell Research Institute Shanghai Jiao Tong University Shanghai 200240 China

This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a storage gas tank and power conditioning unit (PCU). The load is supplied from the PV generator with a fuel cell working in parallel. Excess PV energy when available is converted to hydrogen using an electrolyser for later use in the fuel cell. The individual mathematical model for each component is presented. Control strategy for the system is described. MATLAB/Simulink is used for the simulation of this highly nonlinear hybrid energy system. The simulation results are shown in the paper.

关键词： Photovoltaic (PV) Fuel cell Electrolyser Maximum power point tracking

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang li-Shuo Zheng Yu-Tao Zheng yi-Wei Dong liping Huang Xiaoping Wang Wei jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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