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Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes

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Journal of Animal Science and Biotechnology 2024年第2期15卷 614-631页

作者： Ting Ge Yifan Wen bo Li Xiaoyu Huang Shaohua jiang Enping Zhang Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China

Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of *** the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific *** sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy *** the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA *** A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each ***,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa ***,four granulosa cell subtypes were *** analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa ***,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly *** genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular *** This study provides insights into the molecular mechanisms underlying the high fecundity of Hu *** differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female *** findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development.

关键词： Granulosa cells Hu sheep Lambing number Ovarian somatic cells Single-cell RNA sequencing

Epoxidation of Styrene-Isoprene-Styrene Block Copolymer and Research on Its Reaction Mechanism

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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 403-407页

作者：李红强曾幸荣 college of Materials Science and Engineering South China University of Technology

Styrene-isoprene-styrene（SIS） block copolymer was modified into epoxidized styrene-isoprene-styrene（ESIS） block copolymer with performic acid generated in situ from hydrogen peroxide and formic *** structure and property of ESIS were characterized by Fourier transform infrared（FT-IR） spectroscopy,gel permeation chromatography（GPC）,thermogravimetric/differential thermogravimetric（TG/DTG）,melt flow rate（MFR） and dynamic mechanical analysis（DMA）,and the reaction mechanism in the process of epoxidation was *** results showed that C=C double bonds of 1,4-structure were more active than that of 3,4-structure in polyisoprene *** epoxidation reaction proceeding,the whole tendency of molecular weight increased and molecular weight distribution widened,and MFR firstly increased and latterly *** heat resistance of ESIS was superior to that of *** SIS was changed into ESIS with 15.3% of mass fraction of epoxide groups,Tg of polyisoprene chains increased from-45.3 ℃ to 10.9 ℃.In the earlier period of epoxidation,some molecular chains ruptured and new substances with low molecular weight ***,in the latter period,crosslinking reaction between molecular chains which was initiated by epoxide groups or C=C double bonds occurred and crosslinked insoluble substances came into being.

关键词： styrene-isoprene-styrene block copolymer epoxidation ring-open reaction mechanism

INFLUENCE OF TRACES OF WATER ON THE SYNTHESIS AND ELECTROLUMINESCENCE PROPERTIES OF POLY(2-METHOXY, 5- (2' -ETHYLHEXYL OXY)- 1, 4-PHENYLENE VINYLENE)

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Chinese Journal of Polymer Science 2002年第5期20卷 461-465页

作者： Yue-qi Mo Jian Huang Jia-xin jiang Xian-yu Deng Yu-hua Niu Yong Cao Institute of Optoelectronic Materials & Devices Colleg of Material Science and Engineering south china university of technology,guangzhou 510640,china Institute of Optoelectronic Materials & Devices College of Material Science and Engineering South China University of Technology Guangzhou 510640

It was found that traces of water in the reaction medium would result in a great increase of gel and a decrease of Molecular weight of the poly(2-methoxy,5-(2'-ethylhexyloxy)-1,4-phenylene vinylene) during the polymerization, which ultimately led to inferior film qualities and device properties. The device (ITO/PEDOT/MEH-PPV/Ba/Al) with MEH-PPV prepared under dry conditions has an external quantum efficiency of above 2.0%.

关键词： poly(phenylene vinylene) light-emitting diodes

A Kind of Taxation Forecasting Model Based on Genetic Algorithm Optimized BP Neural Network

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微计算机信息 2007年第3期 187-189页

作者： (college of Automation Science and Engineering,south china university of technology,510640,guangzhou)Zhang Shaoqiu Hu Yueming

The author adopts a new combined method of genetic algorithm and local optimization algorithm, instead of traditional BP algorithm, to find the fittest values of weights and biases of the neural network model and then sets up a taxationforecasting model. By simulating this model using the data of certain district,this method has better precision than using BP algorithm only or using genetic algorithm only,and the result is satisfied.

关键词： genetic algorithm neural network taxation model

Parameter identification theory of a complex model based on global optimization method

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3 1 college of Automotive Engineering, south china university of technology, guangzhou 510640, china 2 Beijing Research Institute of Mechanical and Electrical technology, Beijing 100083, china 3 Department of Engineering Mechanics, Tsinghua university, Beijing 100084, china college of Automotive Engineering South China University of Technology Guangzhou China Beijing Research Institute of Mechanical and Electrical technology Beijing China Department of Engineering Mechanics Tsinghua University Beijing China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

Research on a New Kind of ES Based on XML/Web

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厦门大学学报（自然科学版） 2002年第S1期41卷 266-267页

作者： LAI Chao-an, SUN Yan-ming, HUANG Ping, ZHENG Shi-xiong (college of Machine Engineering, south china university of technology, guangzhou 510640, china)

A new knowledge acquisition methodology for mechani ca l knowledge Web was put forward in this paper after discussed the backwards of k nowledge acquisition method for technical document: natural language understandi ng and ES. A kind of united knowledge representation model, which can include ma ny sorts of knowledge carriers and knowledge representation methods, was advance d firstly, and then mechanical knowledge XML tag was designed based on it. Thus, knowledge still stay in primary electronic document, and knowledge document bec ome document knowledge base based on Web with hierarchy. A corresponding method was advanced and a knowledge acquisition system was developed. It can understand user’s questions in natural language and then find the relevant knowledge and execute reasoning and answer the user’s questions according the result of reaso ning and realized the automatic knowledge acquisition from Web knowledge documen t.

关键词： knowledge acquisition knowledge representation XML WWW

Healing the structural defects of spinel MnFe2O4 to enhance the electrocatalytic activity for oxygen reduction reaction

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Journal of Energy chemistry 2024年第10期97卷 12-19页

作者： Manting Tang Yue zou Zhiyong jiang Peiyu Ma Zhiyou Zhou Xiaodi Zhu Jun Bao Shi-Gang Sun National Synchrotron Radiation Laboratory University of Science and Technology of China State Key Laboratory of Physical chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University iChEM (Collaborative Innovation Center of chemistry for Energy Materials) University of Science and Technology of China

Spinel metal oxides containing Mn,Co,or Fe（AB2O4,A/B=Mn/Fe/Co） are one of the most promising nonPt electrocatalysts for oxygen reduction reaction（ORR） in alkaline ***,the low conductivity of metal oxides and the poor intrinsic activities of transition metal sites lead to unsatisfactory ORR *** this study,eutectic molten salt（EMS） treatment is employed to reconstruct the atomic arrangement of MnFe2O4electrocatalyst as a prototype for enhancing ORR *** analyses by using XAFS,soft XAS,XPS,and electrochemical methods reveal that the EMS treatment reduces the oxygen vacancies and spinel inverse in MnFe2O4effectively,which improves the electric conductivity and increases the population of more catalytically active Mn2+sites with tetrahedral ***,the enhanced Mn-O interaction after EMS treatment is conducive to the adsorption and activation of O2,which promotes the first electron transfer step（generally considered as the ratedetermining step） of the ORR *** a result,the EMS treated MnFe2O4catalyst delivers a positive shift of 40 mV in the ORR half-wave potential and a two-fold enhanced mass/specific *** work provides a convenient approach to manipulate the atomic architecture and local electronic structure of spinel oxides as ORR electrocatalysts and a comprehensive understanding of the structureperformance relationship from the molecular/atomic scale.

关键词： Eutectic molten salt Oxygen reduction reaction Oxygen vacancies Spinel inverse Spinel MnFe2O4

Analysis of Dynamic Response of Explosive Disposal Robot to Rough Road Excitation

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武汉理工大学学报 2006年第S2期28卷 513-516页

作者： MO Haijun HUANG Ping HU Qingchun DUAN Fuhai (college of Mechanical Engineering,south china university of technology,guangzhou 510640,china college of Mechanical Engineering South China University of TechnologyGuangzhou 510640China

When the explosive disposal robot traveling over a rough road,it will shake up and down,and generates dynamic ***,the jolt of the explosive disposal robot will result in oscillation and large inertia forces of the explosive,and will effect the stability of the grasped explosive,even cause the explosive slipping from the claw and falling to the ground,which seriously threats the saJety of the robot and around environment.A tracked explosive dispasal robot has been developed at south Chi- na university of *** paper takes the explosive disposal robot and the grasped explosive as study *** fo- cuses on the response analysis of the grasped explosive when the robot traveling over a rough *** the vibration character- istic of the explosive and the effects of the robot moving speeds on the stability of the *** dynamic response of the explosive is obtained by simulation,the results show that the velocity of the robot is a sensitivity influence factor on the oscillation of grasped explosive.

关键词： explosive disposal robot explosive rough road dynamic response

Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2

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Journal of Wuhan university of technology(Materials Science) 2009年第1期24卷 95-99页

作者：张高文 college of chemistry and Environment Hubei University of Technology

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2 for direct methanol fuel cell （DMFC） application were prepared with sulfonated polyether ether ketone（SPEEK） and tetracethoxy silane（TEOS） by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2 is improved obviously and SiO2 disperses uniformly in the polymer matrix and the particle diameter of SiO2 does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2 .

关键词： direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability