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Chemical Research in Chinese Universities 2012年第5期28卷 926-930页

作者： pang yu-wei LUO Long-bo CHEN Yi ZHANG Peng WANG Xu PENG Chao-rong LIU Xiang-yang State key Laboratory of Polymer Material and Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065P.R.China Sichuan Institute of Atomic Energy Chengdu 610066P.R.China

A diamine monomer 4,4′-methylenedianiline（MDA） was introduced to modify the polyimide of pyromellitic dianhydride（PMDA） and 4,4′-oxydianiline（ODA） by polycondensation. A series of polyamic acids was synthesized from MDA and ODA of different molar ratios with PMDA of sum mole of moles of MDA and ODA, and polyimide films were obtained by thermal imidization. Polyimide（PI） films were characterized by tensile testing, dynamic mechanical analysis（DMA）, thermal gravimetry analysis（TGA）, Fourier transform infrared spectroscopy （FTIR）, wide X-ray diffraction（WAXD） and molecular simulation. With the increase of MDA content, the tensile strength and thermal decomposition temperature remained generally stable compared with those of PMDA/ODA polyimide. Unexpectedly, the glass transition temperature（Tg） and Young＇s modulus increased from 388.7 °C and 2.37 GPa to 408.3 °C and 5.74 GPa, respectively. The results of WAXD and molecular simulation indicate the steric hindrance among hydrogen atoms of the linkage groups and adjacent phenyls enhanced the properties of the polyimide modified with MDA.

关键词： Polyimide Modification Glass transition temperature Steric hindrance

Cloud-Model-Based Feature Engineering to Analyze the Energy-Water Nexus of a Full-Scale Wastewater Treatment Plant

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Engineering 2024年第5期36卷 63-75页

作者： Shan-Shan Yang Xin-Lei yu Chen-Hao Cui Jie Ding Lei He wei Dai Han-Jun Sun Shun-Wen Bai yu Tao Ji-wei pang Nan-Qi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150000China Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China China Energy Conservation and Environmental Protection Group Beijing 100089China

Wastewater treatment plants(WWTPs)are important and energy-intensive municipal *** energy consumption and relatively low operating performance are major challenges from the perspective of carbon ***,water-energy nexus analysis and models for WWTPs have rarely been reported to *** this study,a cloud-model-based energy consumption analysis(CMECA)of a WWTP was conducted to explore the relationship between influent and energy consumption by clustering its influent’s *** principal component analysis(PCA)and K-means clustering were applied to classify the influent condition using water quality and volume *** energy consumption of the WWTP is divided into five standard evaluation levels,and its cloud digital characteristics(CDCs)were extracted according to bilateral constraints and golden ratio *** results showed that the energy consumption distribution gradually dispersed and deviated from the Gaussian distribution with decreased water concentration and *** days with high energy efficiency were extracted via the clustering method from the influent category of excessive energy consumption,represented by a compact-type energy consumption distribution curve to identify the influent conditions that affect the steady distribution of energy *** local WWTP has high energy consumption with 0.3613 kW·h·m^(-3)despite low influent concentration and volumes,across four consumption levels from low(I)to relatively high(IV),showing an unsatisfactory operation and management *** average oxygenation capacity,internal reflux ratio,and external reflux ratio during high energy efficiency days recognized by further clustering were obtained(0.2924-0.3703 kg O_(2)·m^(-3),1.9576-2.4787,and 0.6603-0.8361,respectively),which could be used as a guide for the days with low energy ***,this study offers a water-energy nexus analysis method to identify influent conditions with operational manageme

关键词： Wastewater treatment plants Cloud-model theory Data mining Principal component analysis K-means clustering Cloud-model-based energy consumption analysis

Influence of cromolyn sodium and compound 48/80 administered prior to and after reperfusion on the third day＇s survival rate in a rat intestinal ischemia model

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Chinese Medical Journal 2008年第18期121卷 1843-1847页

作者： HEI Zi-qing HUANG Pin-jie GAN Xiao-liang pang Hong-yu wei Jing Department of Anesthesiology Third Affiliated Hospital Sun Yat-Sen University Guangzhou Guangdong 510630 China

Intestinal ischemia occurs in a wide variety of clinical manifestations. The gut barrier is broken down by bacterial translocation after small intestinal ischemia reperfusion injury （IIRI）, which can result in many clinical consequences, even death. The intestinal mucosal mast cells （IMMCs） serve as a unique cellular source of large amounts of vasoactive mediators, and they can influence local tissue reactions. We and others have previously shown that IIRI could activate IMMCs, make them degranulate and release a mass of inflammatory mediators, which in turn aggravate IIRI.

关键词： intestinal ischemia reperfusion cromolyn sodium compound 48/80 mast cells survival rate

***2 regulates plant height by affecting the main inflorescence length and first effective branch height in Brassica napus L.

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The Crop Journal 2024年第4期12卷 1102-1111页

作者： Chengke pang Jun yu Liang Zhang Min Tang Hongfang Liu Ying Cai Feng Chen Jiefu Zhang wei Hua Xiaodong Wang Ming Zheng Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences Key Laboratory of Biology and Genetic Improvement of Oil CropsMinistry of Agriculture and Rural AffairsWuhan 430062HubeiChina Key Laboratory of Cotton and Rapeseed Ministry of Agriculture and Rural AffairsKey Laboratory of Jiangsu Province for AgrobiologyInstitute of Industrial CropsJiangsu Academy of Agricultural SciencesNanjing 210014JiangsuChina National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070HubeiChina

Rapeseed(Brassica napus L.)is one of the main oil crops in the world,and increasing its yield is of great significance for ensuring the safety of edible ***,improving rapeseed plant architecture is an effective way to increase rapeseed yield with higher planting ***,the regulatory mechanism of rapeseed plant architecture is poorly *** this study,a dwarf rapeseed mutant dwarf08(df08)is obtained by ethyl methane sulfonate(EMS)-*** decrease in plant height of df08 is mainly caused by the reduction in main inflorescence length and first effective branch height and controlled by a single semi-dominant *** hybrid plants(F1)show a semi-dwarf *** map-based cloning and transgenic assay,we confirm that the nonsynonymous single nucleotide variant(SNV)(C to T)in ***2,which is homologous with Arabidopsis(Arabidopsis thaliana)BIN2,is responsible for the dwarfism of ***2 interacts with BnaBZR1/BES1 and involves in brassinosteroids(BRs)signal *** to Leucine substitution in 284(P284L)enhances the protein stability of ***2-D,disrupts BRs signal transduction and affects the expression of genes regulating cell division,leading to dwarfism of *** study provides a new insight for the mechanism of rapeseed plant height regulation and creates an elite germplasm that can be used for genetic improvement of rapeseed architecture.

关键词： Brassica napus Plant height Brassinosteroids BIN2

Relative Broken Family Sensitivity

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2297-2306页

作者： Zhuo wei LIU Tao yu Department of Mathematics Shantou UniversityShantou 515063P.R.China

Letπ:(X,T)→(Y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of *** introduce the notion of relative broken *** Fs(***,Finf)be the families consisting of all syndetic subsets(*** upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(Y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not *** a factor mapπ:(X,T)→(Y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor.

关键词： Relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor

An experimental study on effects of temperature gradient on microstructure of a 308L stainless steel manufactured by directed energy deposition

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Journal of Iron and Steel Research International 2024年第8期31卷 2031-2040页

作者： Ting Dai De-yu Gu yu-wen Qiu wei Guo Hui Ding Yi-wei Sun School of Materials Science and Engineering Jiangsu Key Laboratory of Advanced Metallic MaterialsSoutheast UniversityNanjing 211189JiangsuChina

The effect of spatial temperature gradient on the microstructural evolution of a 308L stainless steel during the directed energy deposition(DED)process was experimentally investigated.A novel cooling system was designed and incorporated to a DED system in order to control the temperature gradient along the deposition direction during *** deposition,the workpiece was placed on a lifting platform,and as the deposition process proceeded,the platform and workpiece were gradually lowered into cooling water so that the temperature gradient along the deposition direction could be controlled and maintained stable during the deposition *** microstructure characterization results indicated that a deposition strategy with higher G and G/R values(where G is temperature gradient and R is solidification rate)produced finer cellular grains that were better aligned with the deposition direction,while a deposition strategy with lower G and G/R values produced columnar grains with larger primary arm spacing and less aligned with the deposition direction.

关键词： Additive manufacturing Directed energy deposition Stainless steel Microstructure Temperature gradient

Thermodynamic nature of black holes in coexistence region

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 27-32页

作者： Shao-Wen wei yu-Xiao Liu Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory of Quantum Theory and Applications of Mo ELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China

Studying the system state of coexistence regions will peek into to reveal microscopic interactions between different phases of a thermodynamic ***,there is no effective method to study thermodynamic nature of the coexistence black hole regions for the failure of the equation of *** at these coexistence states,in this work,we develop a general approach by introducing two new ratio *** first one is the ratio of the horizon radii of the saturated coexistence small and large black holes,and the second one measures that of the small black hole molecule number to the total molecule *** demonstrate that the first parameter can serve as an order parameter to characterize the first-order phase *** study also shows that the black hole state in the coexistence region is uniquely determined by these two introduced parameters bounded between 0 and *** results are quite significant in the analytical study of phase transition and the microscopic nature of black hole in the coexistence regions.

关键词： transition. state. thermodynamic

Dynamic Simulation of Distribution Networks Using Multi-stage Discontinuous Galerkin Method

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 185-196页

作者： Ruizhi yu wei Gu weiqi Liu Peixin Li wei Liu School of Electrical Engineering Southeast UniversityNanjing 210096China. the School of Electrical Engineering Southeast UniversityNanjing 210096China School of Automation Nanjing University of Science and TechnologyNanjing 210094China

Dynamic simulation plays a fundamental role in security evaluation of distribution networks(DNs).However,the strong stiffness and non-linearity of distributed generation(DG)models in DNs bring about burdensome computation and noteworthy instability on traditional methods which hampers the rapid response of simulation ***,a novel L-stable approximate analytical method with high accuracy is proposed to handle these *** method referred to as multistage discontinuous Galerkin method(MDGM),first derives approximate analytical solutions(AASs)of state variables which are explicit symbolic expressions concerning system ***,in each time window,it substitutes values for symbolic variables and trajectories of state variables are obtained *** paper applies MDGM to DG models to derive ***-truncation-error-based variable step size strategy is also developed to further improve simulation *** addition,this paper establishes detailed MDGM-based dynamic simulation *** case studies on a numerical problem,a modified 33-bus system and a practical large-scale DN,it can be seen that proposed method demonstrates fast and dependable performance compared with the traditional trapezoidal method.

关键词： Approximate analytical method distribution network distributed generation dynamic simulation multi-stage discontinuous Galerkin method variable step size

Optical scattering imaging with sub-nanometer precision based on position-ultra-sensitive giant Lamb shift

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 96-105页

作者： Zeyang Liao yu-wei Lu wei Li Xue-Hua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen 518045China

The Lamb shift of a quantum emitter in close proximity to a plasmonic nanostructure can be three or more orders of magnitude larger than that in the free space and is ultra-sensitive to the emitter position and *** demonstrate that this large Lamb shift can be sensitively observed from the scattering or absorption spectrum dip shift of the coupled system when the plasmonic nanoparticle or tip scans the *** these observations,we propose a scanning optical scattering imaging method based on the plasmonic-enhanced Lamb shift with achieves sub-nanometer *** method is based on the scattering or absorption spectrum of the plasmon-emitter coupling system,which is free of the fluorescence quenching problem and easier to implement in a plasmon-emitter coupling *** addition,our scheme works even if the quantum emitter is slightly below the dielectric surface,which can bring about broader applications,such as detecting atoms and molecules or quantum dots above or under a surface.

关键词： Lamb shift plasmon optical scattering imaging

pH-controlled reversible sol-gel inversion by cerous phosphate nanofibers for hemostasis

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Rare Metals 2024年第10期43卷 5141-5151页

作者： Tuo Su Jun-Chen Xu wei yu Dan Su Di-Er Shi Yi-Chao pang Yao Ying Wang-Chang Li Juan Li Jing-Wu Zheng Liang Qiao Sheng-Lei Che Jing yu Research Center of Magnetic and Electronic Materials College of Materials Science and EngineeringZhejiang University of Technology State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang University Key Laboratory of Drug Safety Evaluation and Research of Zhejiang Province Department of Clinical MedicineHangzhou Medical College Department of Chemistry Zhejiang University Clinical Medical College Yangzhou University

Developing biomimetic soft materials that display stimuli responsiveness using solely inorganic materials has been regarded as a challenge owing to that such materials?properties typically vary from those of living ***,biomimetic soft materials have been developed using organic materials or inorganic materials modified with organic small *** this study,we prepared cerium phosphate nanofibers （CePO4NFs） by using inorganic agents only without further *** CePO4NFs demonstrate sol-ge switching properties in response to pH value,allowing them to form a gel under high hydroxide ion （OH-） concentrations and turn back into sol under low *** formation of gel could be ascribed to the physical cross-linking of the nanofibers induced by the attractive electrostatic force of OH-and surface Ce3+.As a result,CePO4NFs are able to form a gel when in contac with blood of high pH value for *** specific clotting mechanism makes them better candidates for hemostasis of heavy bleeding.

关键词： Cerium phosphate nanofibers Hemostasis pH-responsive Reversible Sol-gel switching