检索结果-南通市图书馆

Research and application of the angular rolling technology for plate mill

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2023年第3期11卷 462-476页

作者： zhi-Jie Jiao Jun-Yi Luo Zhi-Qiang Wang zhi-Peng Xu Chun-Yu He Zhong Zhao State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819People's Republic of China

Angular rolling technology can overcome the size limitation of plate mill equipment and product heavy steel plate with large unit weight or improve the production efficiency of small width spreading ratio product.With the DEFORM software,the numerical simulation study of the angular rolling process was carried out,and the relation laws of the width,rolling force and strain of the rolled piece under different angular rolling process conditions were obtained.The simulation results show that with the rotation angle increasing,the width of the rolled piece increases.Comparing with the conventional rolling process,the rolling force changes gradually during the biting and throwing stage of the angular rolling pass.With the rotation angle increasing,both the equivalent strains in the thickness direction and in the width direction gradually increase.According to the pattern and dimension's changing formula in the double-pass angular rolling process,the prediction model of angle,reduction and width spreading is built.The opening value of side guide is set for the rotation angle controlling.For one 5000 mm heavy plate mill,the automation control system was modified,and the angular rolling technology was applied online.The absolute deviation of target width does not exceed±20 mm and the relative deviation does not exceed 1%.The large unit weight plate that cannot be rolled with traditional process,can be produced now,and the annual output increases by 10000 t.

关键词： Plate mill Angular rolling Numerical simulation Width spreading Prediction model Online application

Flowback and early-time production modeling of unconventional gas wells using an improved semi-analytical method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2023年第6期20卷 3441-3449页

作者： Miao Zhang Kien Nguyen Zhi-Qiang Wang Luis F.Ayala College of Petroleum Engineering China University of PetroleumBeijing102249China University of Tulsa USA The Pennsylvania State University USA

Multiple fractured horizontal wells (MFHWs) currently are the only possible means of commercial production from the low and ultra-low permeability unconventional gas reservoirs. In early production time, flowback fluid, which constitutes of hydraulic water and gas flow within fractures, is collected and analyzed. Flowback analysis has been shown to be a useful tool to estimate key properties of the hydraulic fracture such as conductivity and pore volume. Until date, most tools of flowback analysis rely on empirical and approximate methods. This study presents an improved Green-function-based semi-analytical solution for performance analysis of horizontal gas wells during flowback and early production periods. The proposed solution is derived based on coupling the solutions of two domains: a rigorously derived Green’s function-based integral solution for single-phase gas flow in matrix, and a finite-difference, multiphase solution for gas–water two-phase flow in the fracture. The validity of proposed semi-analytical solution is verified by finely gridded numerical models built in a commercial simulator for a series of synthetic cases considering a variety of fluid and reservoir property combinations, as well as various different production constraints. Comparisons against available empirical and approximate methods are also provided for these cases.

关键词： Hydraulic fractures Flowback Unconventional gas wells

Palladium-catalyzed alkynylative[5+1]carboannulation of 1,3-diarylprop-2-yn-1-yl acetates with terminal alkynes enabled by C-H functionalization

在线全文

学校读者我要写书评

暂无评论

Organic Chemistry Frontiers 2022年第5期9卷 1389-1394页

作者： Jiang-Xi Yu Li-Jun Wu Zhi-Qiang Wang zhi-Feng Xu Jin-Heng Li Key Laboratory of Functional Meta-Organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials(University of Hunan Province)Hengyang Normal UniversityHengyang 421008China College of Sciences Central South University of Forestry and TechnologyChangsha410004China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 475004China

A new method for the synthesis of 3-ethynyl-1-methylene-1,2-dihydronaphthalenes via copper-pro-moted palladium-catalyzed intermolecular alkynylative[5+1]carboannulation of 1-arylphenyl-prop-2-yn-1-yl acetates involving C–H functionalization is described.Two terminal alkyne molecules serve as an alkynylation reagent and a one-carbon unit to enable alkynylative[5+1]carboannulation with excellent selectivity control,broad substrate scope and good tolerance of functional groups.

关键词： catalyzed Palladium palladium

Peripheral blood transcriptome analysis of patients with ovarian hyperstimulation syndrome through high-throughput sequencing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Reproductive and Developmental Medicine 2023年第2期7卷 115-121页

作者： Bo Yan Bin Wu Zhi-Qiang Wang Yan Wei Ya-Li Ni Reproductive Medicine Center Gansu Provincial Maternity and Child-Care HospitalLanzhou 730050China Reproductive Medicine Department Central Hospital Affiliated to Shandong First Medical UniversityJinan 250000China

Objective:Ovarian hyperstimulation syndrome(OHSS)is a frequent iatrogenic complication that arises during assisted reproduction and accounts for approximately 30%of all in vitro fertilization cycles.Using high-throughput sequencing,we investigated the peripheral blood transcriptome of patients with OHSS.Methods:Peripheral blood samples were obtained from 15 patients in each of the OHSS high-risk and low-risk groups on the ovum pick-up day.Subsequently,high-throughput sequencing was used to obtain the peripheral blood transcriptomes of five patients each from the high-and low-risk groups.Bioinformatic tools were used for mRNA expression profile mapping and screening of differentially expressed genes(DEGs).Bioinformatics techniques were also implemented in the Kyoto Encyclopedia of Genes Genomes(KEGG)signal pathway,Gene Ontology(GO)function,and protein-protein interaction(PPI)network analyses of DEGs.Results:A total of 20,031 genes were identified and 148 were found to be differentially expressed(P0.58),with 52 upregulated and 96 downregulated genes.GO and KEGG analyses indicated that these genes were involved in extracellular corpuscles(GO:0070062),plasma membrane(GO:0005886),extracellular regions(GO:0005576),immune system response(GO:0006955),PI3K-Akt signaling pathways(hsa04151),cell adhesion molecules(CAMs,hsa04514),focal adhesion(hsa04510),and complement and coagulation cascades(hsa04610).The PPI network and realtime fluorescence quantitative polymerase chain reaction(qPCR)verification predicted that complement C3,von Willebrand factor,and vascular cell adhesion protein 1 proteins are highly implicated in OHSS and may serve as potential biomarkers for future OHSS studies.Conclusion:Transcriptome analysis revealed several DEGs related to OHSS risk factors in the peripheral blood,indicating that these DEGs may be novel players in OHSS development.

关键词： Ovarian hyperstimulation syndrome Transcriptome High-throughput sequencing

On a Class of Quasilinear Elliptic Equations

在线全文

学校读者我要写书评

暂无评论

Communications in Mathematical Research 2023年第2期39卷 209-230页

作者： Sayed Hamid Hashimi Zhi-Qiang Wang Lin Zhang College of Mathematics and Statistics Fujan Normal UniversityFuzhou 350117P.R.China Department of Mathematics and Statistics Utah State UniversityLoganUT 84322USA

We consider a class of quasilinear elliptic boundary problems,including the following Modified Nonlinear Schrödinger Equation as a special case:{Δu+1/2 uΔ(u^(2))−V(x)u+|u|^(q−2)u=0 in Ω,u=0 on∂Ω,whereΩis the entire space R^(N) orΩ⊂R^(N) is a bounded domain with smooth boundary,q∈(2,22^(∗)]with 2^(∗)=2 N/(N−2)being the critical Sobolev exponent and 22^(∗)=4 N/(N−2).We review the general methods developed in the last twenty years or so for the studies of existence,multiplicity,nodal property of the solutions within this range of nonlinearity up to the new critical exponent 4 N/(N−2),which is a unique feature for this class of problems.We also discuss some related and more general problems.

关键词： ariational perturbations p-Laplacian regularization quasilinear elliptic equations modified nonlinear Schrodinger equations sign-changing solutions critical exponents

CO_(2)storage with enhanced gas recovery(CSEGR):A review of experimental and numerical studies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2022年第2期19卷 594-607页

作者： Shu-Yang Liu Bo Ren Hang-Yu Li Yong-zhi Yang Zhi-Qiang Wang Bin wang Jian-Chun Xu Ramesh Agarwal Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Bureau of Economic Geology The Jackson School of GeosciencesThe University of Texas at AustinAustinTXUSA Research Institute of Petroleum Exploration and Development Beijing100083China Tsinghua-Berkeley Shenzhen Institute Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055GuangdongChina Washington University in St.Louis St.LouisMO63130USA

CO_(2)emission mitigation is one of the most critical research frontiers.As a promising option of carbon capture,utilization and storage(CCUS),CO_(2)storage with enhanced gas recovery(CSEGR)can reduce CO_(2)emission by sequestrating it into gas reservoirs and simultaneously enhance natural gas production.Over the past decades,the displacement behaviour of CO_(2)—natural gas has been extensively studied and demonstrated to play a key role on both CO_(2)geologic storage and gas recovery performance.This work thoroughly and critically reviews the experimental and numerical simulation studies of CO_(2)displacing natural gas,along with both CSEGR research and demonstration projects at various scales.The physical property difference between CO_(2)and natural gas,especially density and viscosity,lays the foundation of CSEGR.Previous experiments on displacement behaviour and dispersion characteristics of CO_(2)/natural gas revealed the fundamental mixing characteristics in porous media,which is one key factor of gas recovery efficiency and warrants further study.Preliminary numerical simulations demonstrated that it is technically and economically feasible to apply CSEGR in depleted gas reservoirs.However,CO_(2)preferential flow pathways are easy to form(due to reservoir heterogeneity)and thus adversely compromise CSEGR performance.This preferential flow can be slowed down by connate or injected water.Additionally,the optimization of CO_(2)injection strategies is essential for improving gas recovery and CO_(2)storage,which needs further study.The successful K12—B pilot project provides insightful field-scale knowledge and experience,which paves a good foundation for commercial application.More experiments,simulations,research and demonstration projects are needed to facilitate the maturation of the CSEGR technology.

关键词： Carbon capture Utilization and storage(CCUS) Enhanced gas recovery CO_(2)geologic storage Miscible displacement Dispersion

Co single atoms and nanoparticles dispersed on N-doped carbon nanotube as high-performance catalysts for Zn-air batteries

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第6期41卷 2055-2062页

作者： Jing-Jing Chen Shuai Gu Rui Hao Zhen-Yu wang Mu-Qing Li zhi-qiang Li Kun Liu Ke-Meng Liao Zhi-Qiang Wang He Huang Ying-zhi Li Kai-Li Zhang Zhou-Guang Lu Department of Materials Science and Engineering Guangdong Provincial Key Laboratory of Energy Materials for Electric PowerShenzhen Key Laboratory of Interfacial Science and Engineering of MaterialsSouthern University of Science and TechnologyShenzhen 518055China Department of Mechanical Engineering City University of Hong KongHong Kong 999077China

Diminishing the size of active sites in catalysts is promis-ing to improve the kinetics of oxygen reduction reaction(ORR)and reduce the cost of metal-air batteries.However,the facile preparation of high-performance catalysts with nanoscale active sites still suffers from great challenge.Herein,we report a facile template-free strategy to fabri-cate Co single atoms and nanoparticles dispersed on porous N-doped carbon nanotube(Co-NCNT)by the pyrolysis of the composites of metal-organic complexes and porous carbon nanotube.Different from the conventional strategy,the precursor metal-organic complexes in this work were prepared under mild conditions and used without complex purification procedures.Compared with the pristine carbon nanotube,N-doped carbon nanotube with abundant meso-pores contribute to the formation of nanoscale Co sites.

关键词： nanoparticles composites carbon

Multiple Sign-Changing Solutions for Quasilinear Equations of Bounded Quasilinearity

在线全文

学校读者我要写书评

暂无评论

Analysis in Theory and Applications 2021年第2期37卷 209-229页

作者： Jiaquan Liu Xiangqing Liu Zhi-Qiang Wang LMAM School of Mathematical SciencePeking UniversityBeijing 100871China Department of Mathematics Yunnan Normal UniversityKunmingYunnan 650500China College of Mathematics and Informatics and Center for Applied Mathematics of Fujian Province(FJNU) Fujian Normal UniversityFuzhouFujian 350117China Department of Mathematics and Statistics Utah State UniversityLoganUT 84322USA

The existence of an infinite sequence of sign-changing solutions are proved for a class of quasilinear elliptic equations under suitable conditions on the quasilinear coefficients and the nonlinearity ■on aΩ ,where Ω∈ C RN is a bounded domain with smooth boundary,and we use du 2u d D;u=x,Dju=;dxjdxj and D2bj;(z)=;bj(2).The main interest of this paper is for the case of bounded quasilinearity bj.The result is proved by an elliptic regularization method involving truncations of both u and the gradient of u.

关键词： Quasilinear elliptic equations sign-changing solution an elliptic regularization method

White Matter“Matters”in Alzheimer’s Disease

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2022年第3期38卷 323-326页

作者： Man-Yu Xu zhi-qiang Xu Yan-Jiang wang Department of Neurology and Center for Clinical Neuroscience Daping HospitalThird Military Medical UniversityChongqing400042China Chongqing Key Laboratory of Ageing and Brain Diseases Chongqing400042China The Institute of Brain and Intelligence Third Military Medical UniversityChongqing400042China

Alzheimer's disease(AD)is a neurodegenerative disease that increasingly burdens many families worldwide.Although AD is generally thought to be closely associated with gray matter,many studies have identified significant changes in white matter as well,including demyelination and function alterations in oligodendrocytes in the AD brain.In addition,Ap plaques,the most important pathological characteristic in AD,are deposited in late-myelinating regions such as the prefrontal and temporal lobes,where myelin is prone to damage[1].All the evidence hints that the changes in myelin are closely associated with the onset and progression of AD,prompting scientists to outline the process of changing myelin in AD and develop novel strategies for the treatment of AD.

关键词： Alzheimer alterations damage