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Chinese Journal of Chemical Engineering 2024年第4期68卷 156-164页

作者： Kexin Zhang wenmin Zhang {1. An Zhe Huang Yanzhen wen Xiangyu Jiao Yongqiang wen College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Key Laboratory for Bioengineering and Sensing Technology Daxing Research InstituteSchool of Chemistry&Biological EngineeringUniversity of Science&Technology BeijingBeijing 100083China

Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on *** stem cells(MSCs)promote diabetic wound *** when MSCs aggregate into multicellular spheroids,their therapeutic effect is ***,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid *** this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous *** thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable *** the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound *** importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound *** NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.

关键词： Electrospinning Homogenization Biomedical engineering Nanomaterials Stem cell spheroids Diabetic wound healing

Corrugated Graphene Paper Reinforced Silicone Resin Composite for Efficient Interface Thermal Management

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Chinese Journal of Polymer Science 2024年第7期42卷 1002-1014,I0010页

作者： Bo-wen Wang {1. Zhang Qing-Xia He Hui-Tao Yu Meng-Meng Qin Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China International Engineering Institute Tianjin UniversityTianjin300350China

With the rapid development of high-power-density electronic devices,interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic ***,there is an urgent demand for advanced thermal interface materials(TIMs)with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating *** achieve this aim,a promising strategy involves vertically arranging highly thermoconductive graphene on ***,with the currently available methods,achieving a balance between low interfacial thermal resistance,bidirectional high thermal conductivity,and large-scale production is ***,we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene *** interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal *** resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 1..4 W·m^(-1.·K^(-1.and in-plane thermal conductivity of 1.0W·m^(-1.·K^(-1.when the thermal filler loading is 1..1.wt%,with a thermal conductivity enhancement per 1.wt%filler loading of 831.,outperforming various graphene structures as *** its high thermal conductivity,low contact thermal resistance,and low compressive modulus,the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700,an advanced commercial TIM,effectively solving the interfacial heat transfer issues in electronic *** novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing.

关键词： Graphene paper Vertically aligned structure Cross-plane thermal conductivity Low compressive modulus Thermal interface material

Epidemiology of Leprosy in China,2021.An Update

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International Journal of Dermatology and Venereology 2024年第1期7卷 35-39页

作者： Ying Shi Pei-wen Sun Le Wang Hong-S{1. Wang Mei-wen Yu {1. Gu National Center for Leprosy Control Chinese Center for Disease Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China

Objective:Leprosy is an infectious diseases that remains a concerning public health *** infection of Mycobacterium leprae still exists at the county level in hard-to-access areas in southwest *** accurate analysis of the prevalence of leprosy in various regions is necessary for the formulation of prevention and control strategies,so we conducted this study to describe the epidemiological characteristics of leprosy in China in 2021.and provide essential information for future national leprosy control and prevention ***:We collected epidemiological data of leprosy from 31.provinces,autonomous regions,and municipalities of China(except for Hong Kong,Macao,and Taiwan)provided by the Leprosy Management Information *** performed a comparative analysis of the epidemiological features of patients with leprosy including age,sex,geographical distribution,and grade of ***:In total,374 newly detected leprosy cases were reported nationwide in China in 2021.giving an incidence rate of 0.27 per million population,which represented a decrease of 7.9%compared with *** the population with leprosy in 2021.that comprised 238 males(63.6%)and 1.6 females(36.4%),1.9%(7/374)were children younger than 1. years,92.8%(347/374)had multibacillary leprosy,and 1..2%(68/374)had grade 2 *** than half of the new leprosy cases(54.8%,205/374)were distributed in southwest *** were 33 relapsed leprosy cases reported in *** the end of 2021.there were 1.897 registered leprosy cases reported nationwide,giving a prevalence rate of 1.35 per million ***:The leprosy epidemic in China shows a downward trend in terms of the prevalence and incidence ***,the high prevalence of leprosy in southwest China is still a matter of concern.

关键词： epidemiology leprosy China newly detected leprosy cases multibacillary leprosy paucibacillary leprosy incidence rate prevalence rate

Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research International 2024年第3期31卷 688-699页

作者： wen-quan Sun S{1.-yi Yong Tie-{1. Yuan Ting-song Yang An-rui He Chao Liu Rui-chun Guo National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation *** the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was *** quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was *** on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental *** thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under ***,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 *** results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite ***,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method

Mechanism and control of nonuniform phase transformation of microalloyed dual-phase steel during cooling process after hot rolling

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Journal of Iron and Steel Research International 2024年第2期31卷 428-441页

作者： wen-quan Sun S{1.-yi Yong Tie-{1. Yuan Chao Liu San-bao Zhou Rui-chun Guo Meng-xia Tang National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China Strip Production Plant Xichang Steel and Vanadium Corporation of Pangang GroupXichang615000SichuanChina

After cooling in the hot rolling process,the metallographic structure of microalloyed dual-phase steel is nonuniform along the rolling direction,while the thickness fluctuation of microalloyed dual-phase steel with a nonuniform metallographic structure will occur during cold *** mechanism of nonuniform phase transformation of microalloyed dual-phase steels was studied during the cooling process after hot rolling,and the nonuniform phase transformation of microalloyed dual-phase steel was regulated during the cooling process after hot rolling through process ***,the empirical equation of phase transformation temperature was measured by a dilatometer considering thermal ***,the phase field and temperature field of laminar cooling process were calculated to provide initial boundary conditions for the finite element *** that,the coupling finite element model of the temperature phase transformation of the strip steel in coiling transportation process was *** simulation results show that the different thermal contact conditions of the microalloyed dual-phase steel during coil transportation lead to uneven cooling of the coil,which leads to nonuniform transformation of the coil along the rolling *** addition,by prolonging the time interval from coiling to unloading,the phenomenon of nonuniform phase transformation of microalloyed dual-phase steel can be effectively *** simulation results are applied to industrial *** application results show that prolonging the time interval from coiling to unloading can effectively improve the nonuniform phase transformation of microalloyed dual-phase steel in the cooling process after hot rolling.

关键词： Microalloyed dual-phase steel Thickness fluctuation Cooling Heat conduction Nonuniform phase transition Finite element method

Value iteration algorithm for continuous-time linear quadratic stochastic optimal control problems

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Science China(Information Sciences) 2024年第2期67卷 170-180页

作者： Guangchen WANG heng ZHANG School of Control Science and Engineering Shandong University

In this study, we investigate a continuous-time infinite-horizon linear quadratic stochastic optimal control problem with multiplicative noise in control and state variables. Using the techniques of stochastic stability, exact observability, and stochastic approximation, a value iteration algorithm is developed to solve the corresponding generalized algebraic Riccati equation. Unlike the existing policy iteration algorithm, this algorithm does not rely on an initial stabilizing control. Further, this algorithm can also be used to compute policy evaluation steps that arise in the policy iteration algorithm. Herein, a simulation example is provided to validate the obtained results.

关键词： stochastic systems optimal control linear quadratic stochastic problem generalized algebraic Riccati equation value iteration algorithm

Cucurbit[7]uril confined phenothiazine bridged bis(bromophenyl pyridine)activated NIR luminescence for lysosome imaging

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Chinese Chemical Letters 2024年第6期35卷 288-292页

作者： Hui-Juan Wang wen-wen Xing Zhen-Hai Yu Yong-Xue Li heng-Yi Zhang Qilin Yu Hongjie Zhu Yao-Yao Wang Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic ChemistryNankai UniversityTianjin 300071China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252000China Key Laboratory of Molecular Microbiology and Technology College of Life SciencesNankai UniversityTianjin 300071China

Macrocycle confinement induced guest near-infrared(NIR)luminescence was research hotspot *** in,we reported a cucurbit[7]uril(CB[7])confined 3,7-bis((E)-2-(pyridin-4-yl)vinyl)-1.-Hphenothiazine bridged bis(4-(4-bromophenyl)pyridine)(G),which not only boosted its NIR luminescence but also realized detection of HClO/ClO^(-)in living cells and lysosome *** spectroscopy experiments were performed to calculate the detection ability of probe G to HClO/ClO^(-)up to 1.7 nmol/*** compared with G,supramolecular probe G■CB[7]formed after encapsulated by CB[7],the detection ability towards HClO/ClO^(-)was improved to 24 nmol/L which was ascribe to the macrocycle CB[7]confinement increasing the fluorescence intensity to 1.3 *** the excitation wavelength changing,the fluorescence red-shifted to 820 nm when excited by 570 nm light,which was used to NIR lysosome ***,the supramolecular assembly G■CB[7]was also successfully used to highly sense to exogenous HClO/ClO^(-)in RAW 264.7 cells and live animal.

关键词： Phenothiazine Supramolecular assembly Macrocycle confined Probe HClO/ClO^(-)

Establishing Modular Cell-Free Expression System for the Biosynthesis of Bicyclomycin from a Chemically Synthesized Cyclodipeptide

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Chinese Journal of Chemistry 2024年第4期42卷 384-390页

作者： Yi-Pei Liu Yu-heng Zhao {1.-Qi Zhang Lian Wu Linjuan Huang Gong-Li Tang Jun-Bin He Shaanxi Natural Carbohydrate Resource Engineering Research Center College of Food Science and TechnologyNorthwest UniversityXi'anShaanxi710069 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences(CAS)CASShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of CAS1 Sub-lane XiangshanHangzhouZhejiang310024 China

Cell-free expression systems have emerged as a versatile and powerful platform for metabolic engineering,biosynthesis and synthetic biology ***,successful examples of the synthesis of complex natural products using this system are still ***,a structurally unique and complex diketopiperazine alkaloid,is a clinically promising antibiotic that selectively inhibits the transcription termination factor ***,we established a modular cell-free expression system with cascade catalysis for the biosynthesis of bicyclomycin from a chemically synthesized *** six cell-free expressed biosynthetic enzymes,including five iron-andα-ketoglutarate-dependent dioxygenases and one cytochrome P450 monooxygenase,were active in converting their substrates to the corresponding *** co-expressed enzymes in the cell-free module were able to complete the related partial *** vitro biosynthesis of bicyclomycin was also achieved by reconstituting the entire biosynthetic pathways(i.e.,six enzymes)using the modular cell-free expression *** study demonstrates that the modular cell-free expression system can be used as a robust and promising platformforthe biosynthesis of complex antibiotics.

关键词： Natural products Bicyclomycin Biosynthesis Iron-andα-ketoglutarate-dependent dioxygenases Cytochrome P450 monooxygenase Cell-freeprotein synthesis Enzyme catalysis

Chiral Phenol-2NO Ligand Cooperation with Achiral Organic Base in the Zn(II)-Catalyzed Asymmetric Alkylation Reaction of Indoles

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Chinese Journal of Chemistry 2024年第13期42卷 1474-1480页

作者： Ke-Lan Xu Yu-heng Wang Xi-Rui Wang Pan Hu Bo-{1. Pan {1.-Jing Zhang Zi-Yue Chen Ying Zhou Xiong-Li Liu National&Local Joint Engineering Research Center for the Exploitation of Homology Resources of Southwest Medicine and Food Guizhou UniversityGuiyangGuizhou 550025China College of Pharmaceutical Sciences Guizhou University of Traditional Chinese MedicineGuiyangGuizhou 550025China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan 450001China

The privileged C_(2)-symmetric rigid phenol-type ligand is more attractive but challenging in asymmetric ***,we designed and synthesized a class of rigid-featured chiral tridentate Phenol-2NO ligands,that incorporate the advantages of both the phenol skeleton and pyrroloimidazolone-based N-oxide moiety,from readily available L-prolinamides in operationally simple two steps and up to 44%overall *** importantly,using an achiral quinoline derivative as an additive,the newly developed Phenol-2NO ligand could serve as the anioic ligand upon deprotonative activation to coordinate to Zn(II)to form a highly enantioselective catalyst for the asymmetric Michael-type Friedel-Crafts alkylation reaction of indoles with 2,*** yields(up to 90%)and high enantioselectivities(up to 99%ee)are obtained for a wide range of substrates under mild *** and DFT calculations revealed the reaction mechanism and the origins of the *** also represented the first activation of phenol-type ligand/metal complex by an achiral organic base as the additive in asymmetric catalysis.

关键词： Phenol-2NO C_(2)-Symmetric Rigid-featured Tridentate ligand Asymmetric catalysis Alkylation Synthesis design Heterocycles

Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example

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China Geology 2024年第1期7卷 26-35页

作者： Yong Li Ming-zheng {1. heng Yu Peng Yang Fei-cui Wang Fu Wang Tianjin Center China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Key Laboratory of Coast Geo-environment China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Tianjin Key Laboratory of Coast Geological Processes and Environmental Safety Tianjin 300170China Hebei University of Environmental Engineering Qinhuangdao 066102China Hebei Engineering Research Center for Ecological Restoration of seaward Rivers and Coastal Waters Qinhuangdao 066102China Department of Earth and Environment Boston UniversityBoston 02215USA

The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global *** on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai *** shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human *** implication of change rule for ecological protection and recovery is also *** should be taken to protect the coastal ecological *** models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal *** research results of present study can provide scientific supports for future coastal protection and management.

关键词： Shoreline Tidal flat Erosion deposition patterns Changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay