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Acta Pharmacologica Sinica 2006年第6期27卷 754-759页

作者： Shao-hong LI~(1,4.Shao-xi CAI~(1,3)Bing LIU~1 Kai-wang MA~1 Zhen-ping WANG~1 xiao-kun LI~2 1 Key Laboratory for Biomechanical and Tissue engineering,State Ministry of Education,college of Bioengineerin,Chongqing university,Chongqing 4.0030,china 2 Gene Medicine engineering Research Center,Jinan university,Guangzhou 510632,china Key Laboratory for Biomechanical and Tissue engineering State Ministry of Education College of Bioengineerin Chongqing University Chongqing China Gene Medicine engineering Research Center Jinan University Guangzhou China

Aim:To construct a sustained drug release system for basic fibroblast growthfactor(bFGF).With this special system,bFGF can be used to repair an injuredperipheral nerve,injured spinal cord,or as a carrier for other drugs that need to bereleased over a long ***:Microsphere composite was prepared byencapsulating bFGF into gelatin particles with poly(lactic-co-glycolic acid)(PLGA)as its *** encapsulation was conducted by a phase ***:The average diameter of the gelatin particle-PLGA microspherecomposite was 5-18μm,and bFGF-loading efficiency was up to 80.5%.The bFGFreleasing experiment indicated that this new composite system could release bFGFcontinuously and protect bFGF from ***:A modifiedapproach was successfully employed to develop a biodegradable system for sus-tained release of the drug of bFGF in vitro.

关键词： poly(lactic-co-glycolic acid) gelatin basic fibroblast growth factor microsphere delayed-action preparations

Forming limits under multi-index constraints in NC bending of aluminum alloy thin-walled tubes with large diameters

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Science china(Technological Sciences) 2010年第2期53卷 326-342页

作者： YAN Jing, YANG He, ZHAN Mei & LI Heng college of Materials Science and engineering, State Key Laboratory of Solidification Processing, Northwestern Polytechnical university, xi’an 710072, china college of Materials Science and engineering State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi’an China

With increasing diameters of aluminum alloy thin-walled tubes (AATTs), the tube forming limits, i.e. the minimum bending factors, and their predictions under multi-index constraints including wrinkling, thinning and flattening have been being a key problem to be urgently solved for improving tube forming potential in numerical control (NC) bending processes of AATTs with large diameters. Thus in this paper, a search algorithm of the forming limits is put forward based on a 3D elastic-plastic finite element (FE) model and a wrinkling energy prediction model for the bending processes under axial compression loading (ACL) or not. This algorithm enables to be considered the effects of process parameter combinations including die, friction parameters on the multi-indices. Based on this algorithm, the forming limits of the different size tubes are obtained, and the roles of the process parameter combinations in enabling the limit bending processes are also revealed. The followings are found: the first, within the appropriate ranges of friction and clearances between the different dies and the tubes enabling the bending processes with smaller bending factors, the ACL enables the tube limit bending processes after a decrease of the mandrel ball thickness and diameters; then, without considering the effects of the tube geometry sizes on the tube constitutive equations, the forming limits will be decided by the limit thinning values for the tubes with diameters smaller than 80 mm, while the wrinkling for the tubes with diameters no less than 80 mm. The forming limits obtained from this algorithm are smaller than the analytical results, and reduced by 57.39%; the last, the roles of the process parameter combinations in enabling the limit bending processes are verified by experimental results.

关键词： forming limit NC tube bending aluminum alloy thin-walled tubes with large diameters multi-index constraints finite element method

Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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Science china Chemistry 2024年第3期67卷 928-935页

作者： xi Zou Boming Shen Gao-lin Li Qian Liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing Gao State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

Effect of near isothermal forging on the microstructure of Ti_3Al/TC11 welding interface

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Rare Metals 2009年第5期28卷 471-477页

作者： LIU Yingying YAOZekun GUO Hongzhen college of Materials Science and engineering Northwestern Polytechnical University Xi＇an 710072 China

The as-forged Ti3Al-based alloy and TC11 titanium alloy were welded by electron beams in vacuum, and then they were processed using near isothermal forging and gradient heat treatment. The experimental results show that the near isothermal forging processing parameters have little effect on the phase constitution of the weld. The weld consists of Ti2AlNb, MoNb, Nb3Al, and TiAl3 phases as well as the two main phases of α and α2. However, the near isothermal forging processing parameters have significant effect on the shape, size, and volume fraction of α and α2 phases of the welding interface. The sizes of the α and α2 phases increase as the strain rate decreases. Because the distortion energy of the lattice and the volume fraction of the grains occurring in dynamic recrystallization increase with an increase in deformation, the sizes of the α and α2 phases of the welding interface decrease.

关键词： Ti3Al-based alloy TCll titanium alloy electron beam welding isothermal forging interface microstructure

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the xiangxi Bay

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Science china(Technological Sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & xiAO ShangBin1,3 1 college of Civil & Hydroelectric engineering,china Three Gorges university,Yi{4. 4.3002,china 2 School of Water Resources & Hydropower engineering,Wuhan university,Wuhan 4.0072,china 3 Institute of Earth Environment,Chinese Academy of Sciences,xi’an 710075,china college of Civil & Hydroelectric engineering China Three Gorges University Yichang China School of Water Resources & Hydropower engineering Wuhan University Wuhan China Institute of Earth Environment Chinese Academy of Sciences Xi’an China

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the xiangxi Bay the Three Gorges Reservoir

Silica-modified Pt/TiO_(2) catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation

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Chinese Journal of Chemical engineering 2024年第6期70卷 189-198页

作者： Zhengjian Hou Yuanyuan Zhu Hua Chi Li Zhao Huijie Wei Yanyan xi Lishuang Ma xiang Feng Xufeng Lin college of Chemistry and Chemical engineering China University of Petroleum(East China)Qingdao 266580China Advanced Chemical engineering and Energy Materials Research Center China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China

Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO_(x) encapsulation of noble metal components to minimize the exposure of noble *** study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles(NPs)with the supported TiO_(2),achieving the moderate suppression of SMSI *** introduction of silica inhibits this encapsulation,as reflected in the characterization results such as XPS and HRTEM,while the Ti^(4.) to Ti^(3+) conversion due to SMSI can still be found on the support ***,the hydrogenation of cinnamaldehyde(CAL)as a probe reaction revealed that once this encapsulation behavior was suppressed,the adsorption capacity of the catalyst for small molecules like H_(2) and CO was enhanced,which thereby improved the catalytic activity and facilitated the hydrogenation of ***,the introduction of SiO_(2) also changed the surface structure of the catalyst,which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C *** manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed.

关键词： Pt catalyst Silica modification Hydrogenation Cinnamaldehyde Strong metal-support interaction

Energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole

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Journal of Hydrodynamics 2024年第3期36卷 435-443页

作者： Dong-qiao He Hai-gang Wen Si-yuan Geng Chen-xi Yang Qiang Zhong Zhi-feng Yao college of Water Resources and Civil engineering China Agricultural UniversityBeijing100083China Powerchina Beijing engineering Corporation Limited Beijing100024China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing100083China Beijing engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

To investigate the energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole,we utilized a nanosecond resolution photography system based on a Q-switched Nd:YAG laser and conventional industrial camera to carefully observe the transient process of bubble collapse near the rigid wall with a gas-containing *** analyzed the generation of collapse microjets and the emission of collapse shock *** found that the cavitation bubble near the rigid wall with a gas-containing hole collapsed at different times and space,and produced various types of shock *** on the far field pressure information of the shock waves measured by hydrophone,the energy of the shock waves generated by the bubble collapse near the rigid wall with a gas-containing hole is calculated for the first *** results show that the ratio of collapse shock wave energy to bubble energy is approximately between 0.7 and 0.8.

关键词： Energy partition bubble collapse laser-induced shock wave gas-containing hole

Oxidation behavior of FeV_(2)O_(4.and FeCr_(2)O_(4.particles in the air:Nonisothermal kinetic and reaction mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1839-1848页

作者： Junyi xiang xi Lu Luwei Bai Hongru Rao Sheng Liu Qingyun Huang Shengqin Zhang Guishang Pei Xuewei Lü School of Metallurgy and Materials engineering Chongqing University of Science and TechnologyChongqing 401331China Department of Materials Science and engineering Seoul National UniversitySeoul 08826Rep.of Korea college of Materials Science and engineering Chongqing UniversityChongqing 400044China

High-temperature oxidation behavior of ferrovanadium(FeV_(2)O_(4.)and ferrochrome(FeCr_(2)O_(4.)spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium ***,the nonisothermal oxidation behavior of FeV_(2)O_(4.and FeCr_(2)O_(4.prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XRD)at heating rates of 5,10,and 15 K/*** apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek ***,in-situ XRD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2)O_(4.and FeCr_(2)O_(4..The results reveal a gradual increase in the overall apparent activation energies for FeV_(2)O_(4.and FeCr_(2)O_(4.during *** stages of the oxidation process are observed based on the oxidation conversion rate of each *** oxidation mechanisms of FeV_(2)O_(4.and FeCr_(2)O_(4.are complex and have distinct *** particular,the chemical reaction controls the entire oxidation process for FeV_(2)O_(4.,whereas that for FeCr_(2)O_(4.transitions from a three-dimensional diffusion model to a chemical reaction *** to the in-situ XRD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4.and V2O_(5)for FeV_(2)O_(4.and Fe_(2)O_(3)and Cr_(2)O_(3)for FeCr_(2)O_(4.,respectively.

关键词： FeV_(2)O_(4. FeCr_(2)O_(4. oxidation nonisothermal kinetics mechanism

Visualization of cristae and mtDNA interactions via STED nanoscopy using a low saturation power probe

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Light(Science & Applications) 2024年第9期13卷 1741-1756页

作者： Wei Ren xichuan Ge Meiqi Li Jing Sun Shiyi Li Shu Gao Chunyan Shan Baoxiang Gao Peng xi Department of Biomedical engineering National Biomedical Imaging CenterCollege of Future TechnologyPeking UniversityBeijing 100871China Key Laboratory of Analytical Science and Technology of Hebei Province College of Chemistry and Material ScienceHebei UniversityBaoding 071002China School of Life Sciences Peking UniversityBeijing 100871China National Center for Protein Sciences Peking UniversityBeijing 100871China

Mitochondria are crucial organelles closely associated with cellular metabolism and *** DNA(mtDNA)encodes a variety of transcripts and proteins essential for cellular ***,the interaction between the inner membrane(IM)and mtDNA remains elusive due to the limitations in spatiotemporal resolution offered by conventional microscopy and the absence of suitable in vivo probes specifically targeting the ***,we have developed a novel fluorescence probe called HBmito Crimson,characterized by exceptional photostability,fluorogenicity within lipid membranes,and low saturation *** successfully achieved over 500 frames of lowpower stimulated emission depletion microscopy(STED)imaging to visualize the IM dynamics,with a spatial resolution of 4. *** utilizing dual-color imaging of the IM and mtDNA,it has been uncovered that mtDNA tends to habitat at mitochondrial tips or branch points,exhibiting an overall spatially uniform ***,the dynamics of mitochondria are intricately associated with the positioning of mtDNA,and fusion consistently occurs in close proximity to mtDNA to minimize pressure during cristae *** healthy cells,>66%of the mitochondria are Class III(i.e.,mitochondria>5μm or with>12 cristae),while it dropped to<18%in *** dynamics,orchestrated by cristae remodeling,foster the even distribution of ***,in conditions of apoptosis and ferroptosis where the cristae structure is compromised,mtDNA distribution becomes *** findings,achieved with unprecedented spatiotemporal resolution,reveal the intricate interplay between cristae and mtDNA and provide insights into the driving forces behind mtDNA distribution.

关键词： metabolism saturation utilizing

The Response of Carbonate System to Watershed Urbanization Process in a Semi-Arid River

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Journal of Ocean university of china 2024年第4期23卷 991-1002页

作者： LI Yunxiao DANG Jiajia HUANG xiao YANG Hong WANG xiao LI Lina BAI Jie CHEN xi Department of Environmental Science College of Resource and EnvironmentShanxi Agricultural UniversityTaigu 030801China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China Department of Geography and Environmental Science University of ReadingWhiteknightsReading RG66ABUK Marine Agriculture Research Center Tobacco Research InstituteChinese Academy of Agricultural SciencesQingdao 266101China 5 Key Laboratory of Marine Environmental Science and Ecology Ministry of EducationCollege of Environmental Science and EngineeringOcean University of ChinaQingdao 266100China

Different from rivers in humid areas,the variability of riverine CO_(2) system in arid areas is heavily impacted by anthropogenic disturbance with the increasing urbanization and water *** this study,the water chemistry and the controls of carbonate system in an urbanized river(the Fenhe River)on the semi-arid Loess Plateau were *** water chemistry of the river water showed that the high dissolved inorganic carbon(DIC)concentration(about 37 mg L^(-1))in the upstream with a karst land type was mainly sourced from carbonate weathering involved by H_(2)CO_(3) and H_(2)SO_(4.,resulting in an oversaturated partial pressure of CO_(2)(pCO_(2))(about 800μatm).In comparison,damming resulted in the widespread appearance of non-free flowing river segments,and aquatic photosynthesis dominated the DIC and pCO_(2) spatiality demonstrated by the enriched stable isotope of DIC(δ^(13)CDIC).Especially in the mid-downstream flowing through major cities in warm and low-runoff August,some river segments even acted as an atmospheric CO_(2) *** noteworthy is wastewater input leading to a sudden increase in DIC(>55 mg L^(-1))and pCO_(2)(>4.00μatm)in the downstream of Taiyuan City,and in cold November the increased DIC even extended to the outlet of the *** results highlight the effects of aquatic production induced by damming and urban sewage input on riverine CO_(2) system in semi-arid areas,and reducing sewage discharge may mitigate CO_(2) emission from the rivers.

关键词： dissolved inorganic carbon stable carbon isotope carbonate weathering aquatic photosynthesis sewage input the Fenhe River