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Chemical Research in Chinese Universities 2010年第1期26卷 142-147页

作者： yang Hong-mei yang Yong-zhu HE Xiao ZHENG Qiang ZHOU Hou-qiang Department of Polymer Science and Engineering Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Zhejiang University Hangzhou 310027 P. R. China Ningbo Dongfang Cable Ltd. Ningbo 315040 R R. China

Two commercial crosslinkable polyethylene insulation cable granules, designed for 110 and 35 kV voltage insulation, with similar crosslinking temperature but different melting temperature, were chosen as experimental samples for examining their linear dynamic responses during cross-linking. It has been found that the gel contents of cable compounds for 110 and 35 kV insulation are almost the same after they have been cross-linked at the same temperature, pressure and time. And the sample melts show the similar dependence of the dynamic storage modulus, G; on strain. On the other hand, the dynamic temperature ramp test and the dynamic time sweep test indicate that the samples exhibit different dynamic viscoelastic responses during their crosslinking. An expression for describing their erosslinking process was proposed via probing rheokinetics of crosslinking for the two samples.

关键词： XLPE Insulation cable Crosslinking Rheological behavior

Spatial distribution of snow depth based on geographically weighted regression kriging in the Bayanbulak Basin of the Tianshan Mountains, China

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Journal of Mountain Science 2018年第1期15卷 33-45页

作者： LIU yang LI Lan-hai CHEN Xi yang Jin-Ming HAO Jian-Sheng State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia No.818 South Beijing Road Urumqi 830011 China Institute of Arid Ecology and Environment Xinjiang University Urumqi 830046 China

Snow depth is a general input variable in many models of agriculture,hydrology,climate and *** study makes use of observational data of snow depth and explanatory variables to compare the accuracy and effect of geographically weighted regression kriging(GWRK)and regression kriging(RK)in a spatial interpolation of regional snow *** auxiliary variables are analyzed using correlation coefficients and the variance inflation factor(VIF).Three variables,Height,topographic ruggedness index(TRI),and land surface temperature(LST),are used as explanatory variables to establish a regression model for snow *** estimated spatial distribution of snow depth in the Bayanbulak Basin of the Tianshan Mountains in China with a spatial resolution of 1 km is *** results indicate that 1)the result of GWRK's accuracy is slightly higher than that of RK(R^2=0.55 vs.R^2=0.50,RMSE(root mean square error)=0.102 m ***=0.077 m);2)for the subareas,GWRK and RK exhibit similar estimation results of snow *** in the Bayanbulak Basin with a snow depth greater than 0.15m are mainly distributed in an elevation range of 2632.00–3269.00 m and the snow in this area comprises 45.00–46.00% of the total amount of snow in this ***,the GWRK resulted in more detailed information on snow depth distribution than the *** final conclusion is that GWRK is better suited for estimating regional snow depth distribution.

关键词： Snow depth Spatial distribution Regression kriging Geographically weighted regression kriging

Operating conditions combination analysis method of optimal water management state for PEM fuel cell

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Green Energy and Intelligent Transportation 2023年第4期2卷 28-42页

作者： Wenxin Wan yang yang yang Li Changjun Xie Jie Song Zhanfeng Deng Jinting Tan Ruiming Zhang School of Automation Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan430070China Department of Electrical Engineering Chalmers University of TechnologyGothenburg41258Sweden Modern Industry College of Artificial Intelligence and New Energy Vehicles Wuhan University of TechnologyWuhan430070China Global Energy Interconnection Research Institute Beijing102211China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Guangdong Hydrogen Energy Institute of Wuhan University of Technology Foshan528000China

The water content of proton exchange membrane fuel cells(PEMFCs)affects the transport of reactants and the conductivity of the *** water management measures can improve the performance and extend the lifespan of the fuel *** water management state of the stack is influenced by various external operating conditions,and optimizing the combination of these conditions can improve the water management state within the *** that the stack's internal resistance can reflect its water management state,this study first establishes an internal resistance-operating condition model that considers the coupling effect of temperature and humidity to determine the variation trend of total resistance and stack humidity with single-factor operating ***,the water management state optimization method based on the ANN-HGPSO algorithm is proposed,which not only quantitatively evaluates the influence weights of different operating conditions on the stack's internal resistance but also efficiently and accurately obtains the optimal combination of five operating conditions:working temperature,anode gas pressure,cathode gas pressure,anode gas humidity,and cathode gas humidity to achieve the optimal water management state in the stack,within the entire range of current ***,the response surface experimental results of the stack also validate the effectiveness and accuracy of the ANN-HGPSO *** method mentioned in this article can provide effective strategies for efficient water management and output performance optimization control of PEMFC stacks.

关键词： PEMFC Water management statue Internal resistance-operating condition model Operating condition optimization Response surface method

Ultrasound-responsive Homopolymer Nanoparticles

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Chinese Journal of Polymer Science 2020年第4期38卷 349-356,I0006页

作者： Bo yang Jian-Zhong Du Department of Orthopedics Shanghai Tenth People's HospitalTongji University School of MedicineShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringKey Laboratory of Advanced Civil Engineering Materials of Ministry of EducationTongji UniversityShanghai201804China

Nonin vasive ultraso und is a more effective strategy for on-demand drug delivery of polymeric nano particles than many other ***,the preparation of ultrasound-responsive homopolymer nanoparticles is still very *** this study,we disclose the regulating factors of ultrasound responsiveness of homopolymer nanoparticles and the disaggregation behavior of homopolymer nanoparticle *** nanoparticles such as vesicles and large compound micelles(LCMs)are self-assembled from poly(methoxyethyl methacrylate)(PMEMA)and poly(amic acid)(PAA),*** ultrasound responsiveness of PAA vesicles at metastable state could be regulated by tuning the self-assembly temperature(7^),and was optimized when Ts is around the glass transition temperature(7g)of ***,the PMEMA LCMs did not respond to ultrasound as they are at stable *** the other hand,poly(2-(2-ethoxyethoxy)ethyl acrylate)(PEEA)could self-assemble into vesicle aggregates or complex micelle aggregates,which were dissociated upon ***,the above findings provide us with a fresh in sight for designing ultrasound-responsive polymeric nanoparticles.

关键词： Ultrasound responsiveness Homopolymers Vesicles Micelles Self-assembly

Study on the damage-softening constitutive model of rock and experimental verification

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Acta Mechanica Sinica 2019年第4期35卷 786-798页

作者： Sheng-Qi yang Bo Hu Peng Xu State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil Engineering China University of Mining and Technology Xuzhou 221116 China China Construction Third Engineering Design Bureau Co. Ltd Wuhan 430064 China

A damage-softening model is presented to describe the stress-strain curve of rock. By comparing the Hoek-Brown (H-B) and Mohr-Coulomb (M-C) yield criterion, the equivalent M-C yield criterion is selected as the strength criterion in this model. To better characterize the rock damage and failure processes with considering the relationship between damage and deformation, the concept of yield stress ratio is introduced to describe the yield strengthening deformation before rock peak stress. Damage events are described by two cumulative damage evolution laws. The evolution equations of tensile and shear damage are presented based on the equivalent plastic strains and the maximum value between tensile and shear damage represents the total damage for rock. Considering that rock cannot bear tensile load after tensile failure but still has a certain shear strength, its tensile and shear strengths are small after shear failure. The elastic modulus is affected by tensile damage, whereas the angle of internal friction, the cohesion, and dilation angles are influenced by shear damage. The proposed damage-softening model describes the strain-softening, brittle stress-drop, and residual strength of rock after peak stress, and finally the model is implemented in FLAC3D. Comparing the test and the numerical calculation results, the damage-softening model better describes the total stress-strain curve of rock.

关键词： Rock deformation Damage evolution Softening Numerical calculation

Visible-Light-Catalyzed Phosphonation-Annulation： An Efficient Strategyto Synthesize β-Phosphonopyrrolidines and β-Phosphonolactones

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Chinese Journal of Chemistry 2018年第11期36卷 1052-1058页

作者： Chong Li Zhi-Chao Qi Qiang yang Xiao-Yue Qiang Shang-Dong yang State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences LanzhouGansu 730000 China

A new type of phosphine radical precursor for C—P bond formation has been developed and successfully used in visible‐light‐catalyzed phosphonation‐annulation of unsaturated sulfonamides and carboxylic acids. The catalytic process is simple and green accessible, and no additional oxidant or base is needed. Mechanistic studies suggest that the reaction proceeds via a single electron transfer pathway.

关键词： phosphanes heterocycles annulation photocatalysis radicals

Active disturbance rejection control for hydraulic width control system for rough mill

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1429-1434页

作者： ZOU Jun FU Xin yang Hua-yong Institute State Key Laboratoty of Fhtid Power Transmission and Control. Zhejiang University Hangzhou 310027 China

The highly nonlinear behavior of the system limits the performance of classical linear proportional and integral （PI） controllers used for hot rolling. An active disturbance rejection controller is proposed in this paper to deal with the nonlinear problem of hydraulic servo system in order to preserve last response and small overshoot of control system. The active disturbance rejection （ADR） controller is composed of nonlinear tracking differentiator （TD）, extended state observer （ESO） and nonlinear feedback （NF） law. An example of the hydraulic edger system case study is investigated to show the effectiveness and robustness of the proposed nonlinear controller, especially, in the circumstance of foreign disturbance and working condition variation, compared with classic PI controller.

关键词： Active disturbance rejection (ADR) Hydraulic servo system Width control Rough mill

An epi-allele of SMS causes Sanming dominant genic male sterility in rice

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Science China(Life Sciences) 2023年第12期66卷 2701-2710页

作者： Yachun yang Cheng Zhang Hao Li Zeyuan yang Zuntao Xu Dewei Tai Dahu Ni Pengcheng Wei Chengxin Yi Jianbo yang Yong Ding Rice Research Institute Anhui Academy of Agricultural SciencesHefei 230036China Institute of Health and Medicine Hefei Comprehesive National Science CenterHefei 230031China Ministry of Education Key Laboratory for Membraneless Organelles and Cellular Dynamics School of Life SciencesDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China

Male sterility is an important trait in rice for hybrid rice(Oryza sativa)***,the factors involved in dominant male sterility are largely ***,we identified a gene from Sanming dominant genic male sterile rice,named Sanming dominant male sterility(SMS),and reported that an epi-allele of this locus contributes to male *** analysis attributed dominant male sterility to a single locus,SMS,which we characterized using a male-sterile near isogenic line(NIL)of rice cultivar *** SMS locus was heterozygous in the male-sterile 93-11 NIL,containing an epi-allele identical to that in 93-11,and an epi-allele identical to that in rice cultivar Nipponbare,which we refer to as SMS9 and SMSN,***9is silent and hyper-methylated,whereas SMSNis expressed and hypo-methylated in the 93-11 *** SMSNled to male *** in SMS rescued the male sterility of the 93-11 ***,we observed the duplication of SMSN in Nipponbare,but did not observe the duplication of SMS9in ***,these findings suggest that the reduced methylation and enhanced expression of the SMSNepi-allele in the 93-11 NIL is responsible for its role in conferring dominant male sterility.

关键词： male sterility rice epi-allele Sanming DNA methylation

Design and Performance Study of an Ultrasonic Bone Scalpel with Composite Horn Structure

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Nanomanufacturing and Metrology 2023年第1期6卷 24-35页

作者： Jieping Wu Yong yang Zhao yang Cong Chen Shuai Huang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China National Engineering Research Center For High Efficiency Grinding Hunan UniversityChangsha 410082China

The ultrasonic bone scalpel was often used in all kinds of clinical orthopedic surgery as a new type of medical *** on the working theory of the ultrasonic bone scalpel and combined with the design method of a quarter wavelength transducer and horn,this study proposed an optimization design method for the ultrasonic bone scalpel with a composite horn *** structure of the ultrasonic bone scalpel was simplified,and its length was *** element analysis,modal analysis,and harmonic response analysis were used to optimize the design of the ultrasonic bone *** performance of the ultrasonic bone scalpel was explored through impedance analysis,amplitude measurement,temperature measurement,and cutting tests,and the feasibility of the design was verified through torque *** results showed that when the torque force was 4.0 N,the resonance frequency of the ultrasonic bone scalpel was 30,540 Hz,and the maximum amplitude of the ultrasonic bone scalpel could reach 62μ*** spray cooling,the maximum surface temperature of the rear end cover was reduced from 51.8 to 36.3℃,the maximum surface temperature of the composite horn was reduced from 71 to 45.3℃,and the maximum surface temperature of the cutter head was reduced from 101 to 46.1℃,demonstrating a good cooling *** 89 Voltage,the optimal cutting force for cutting chicken leg bones was 0.1 N,the optimal cutting force for cutting pork ribs was 0.3 N,and the cutting process showed tissue selectivity.

关键词： Ultrasonic bone scalpel Transducer Horn Modal analysis Harmonic response analysis

DEM analysis of the effect of electrostatic interaction on particle mixing for carrier-based dry powder inhaler formulations

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Particuology 2015年第6期13卷 25-30页

作者： Jiecheng yang Chuan-Yu Wu Michael Adams School of Chemical Engineering University of Birmingham Birmingham BI5 2Tr UK Department of Chemical and Process Engineering University ofSu-rrey Guildford GU2 ZXH UK

Particle interactions play a significant role in controlling the performance of dry powder inhalers （DPIs）, which mainly arise through van der Waals potentials, electrostatic interactions, and capillary forces. Our aim is to investigate the influence of electrostatic charge on the performance of DPIs as a basis for improv- ing the formulation of the particle ingredients. The mixing process of carrier and active pharmaceutical ingredient （API） particles in a vibrating container is investigated using a discrete element method （DEM）. The number of APl particles attaching to the carrier particle （i.e., contact number） increases with increas- ing charge and decreases with increasing container size. The contact number decreases with increasing vibrational velocity amplitude and frequency. Moreover, a mechanism governed by the electrostatic force is proposed for the mixing process. This mechanism is different from that previously proposed for the mixing process governed by van der Waals forces, indicating that long-range and short-range adhesive forces can result in different mixing behaviours.

关键词： Electrostatic Particle mixing Dry powder inhaler Discrete element method