检索结果-南通市图书馆

Fluid Flow Modeling of Arc Plasma and Bath Circulation in DC Electric Arc Furnace

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2006年第5期13卷 7-13页

作者： WANG Feng-hua JIN Zhi-jian ZHU zi-shu School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200030 China

A mathematical model describing the flow field, heat transfer and the electromagnetic phenomenon in a DC electric arc furnace has been developed. First the governing equations in the arc plasma region are solved and the calculated results of heat transfer, current density and shear stresses on the anode surface are used as boundary conditions in a model of molten bath. Then a two-dimensional time-dependent model is used to describe the flow field and electromagnetic phenomenon in the molten bath. Moreover, the effect of bottom electrode diameter on the circulation of molten bath is studied.

关键词： DC electric arc furnace fluid flow heat transfer molten bath

Diabetes mellitus: a “true” independent risk factor for hepatocellular carcinoma?

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2009年第5期8卷 465-473页

作者： Gao, Chun yao, shu-Kun Minist Hlth China Japan Friendship Hosp Dept Gastroenterol Beijing 100029 Peoples R China Chinese Acad Med Sci Beijing 100730 Peoples R China Peking Union Med Coll Grad Sch Beijing 100730 Peoples R China

BACKGROUND:Diabetes mellitus(DM)is thought to be associated with an increased risk of hepatocellular carcinoma(HCC)in some published ***,can we draw the conclusion that DM is a'true'independent risk factor for HCC based on these references? DATA SOURCES:MEDLINE and PubMed searches were conducted for published studies(between January 1966 and June 2009)to identify relevant articles using the keywords 'diabetes','insulin resistance'and'hepatocellular carcinoma',including'primary liver cancer'.Because of the very limited number of relevant articles most were reviewed. RESULTS:This systematic review was conducted from 4 aspects:(1)the significant synergy between DM,hepatitis virus infection,and heavy alcohol consumption in HCC; (2)the role of DM independently in HCC cases while other identified risk factors were controlled or excluded; (3)obesity,DM,and nonalcoholic fatty liver disease in HCC patients;and(4)the impact of DM for the prognosis or surgical treatment in HCC patients with *** consensus has been reached among these studies and it is too early to draw the conclusion that DM is a'true' independent risk factor for HCC. CONCLUSIONS:DM can be regarded as a risk factor for ***,whether DM itself directly predisposes to HCC or whether it is a'true'independent risk factor remains *** issues should be clarified by more research.

关键词： diabetes mellitus hepatocellular carcinoma risk factor

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling Guo shun-Xi Li Yu-Cheng Liu Yu-Long Li Wei shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

关键词：

A Grid Cell Based Distribution Network Planning Method Adapting to the Increasing Permeability of Distributed Resources

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Dianwang Jishu/Power System Technology 2025年第1期49卷 306-315页

作者： Zhou, Yang Wang, Zhuding Zhang, Man Yang, Jie shu, Dongsheng State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Shapingba District Chongqing 400044 China Chongqing Electric Energy Star Inc Jiulongpo District Chongqing 400039 China Economic Research Institute of State Grid Hubei Electric Power Company Hubei Province Wuhan 430000 China

Based upon the existing research findings of distribution network planning，and based on the optimization division of power areas (or grid cells), a heuristic method of distribution network planning, i.e., the grid cell based distribution network planning method, is proposed to adapt to the gradual increase in the penetration rate of distributed resources, wherein the power balancing method involves differential approaches of different space-time-resources and two typical operating modes. The optimization division of grid cells is carried out by the principles of nearby use for distributed power resources and "nearby backup supply", resulting in the regional grid cell, substation grid cell, medium-voltage and low-voltage grid cell in terms of space, and also the energy output type, energy input type and balance type in terms of resources. The real planning example shows that the proposed method has relatively strong operability. © 2025 Power System Technology Press. All rights reserved.

关键词： Power distribution planning

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年第1期68卷 300-302页

作者： Ze-Min Lin Mai Xiang Wen-Hui Wei shu-Hui Fan Li Chen Jie Wang Xiao-Qian Yang Chun-Hao Yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

关键词：

Existence of Positive Solutions for a Singular p-Laplacian Differential Equation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2008年第8期24卷 1331-1344页

作者： Xia LI Zheng An yao Wen shu ZHOU Department of Mathematics Shenzhen University Shenzhen 518060 P. R. China Department of Mathematics Zhongshan University Guangzhou 510275 P. R. China Department of Mathematics Jilin University Changchun 130012 P. R. China

In this paper, we are concerned with the existence of positive solutions for a singular p-Laplacian differential equation（φp（u＇））＇＋β/r φp（u＇）-γ ｜u＇｜^p/u ＋ g（r）=0,0〈r〈1,subject to the Dirichlet boundary conditions： u（0） = u（1） =0, where φp（s） = ｜sl^P-2s,p 〉 2,β 〉0, γ〉（p-1）/p （β ＋ 1）, and g（r） ∈ C^1 [0, 1] with g（r）〉 0 for all τ ∈ [0, 1]. We use the method of elliptic regularization, by carrying out two limit processes, to get a positive solution.

关键词： p-Laplacian differential equation positive solution existence

Human impact recorded in the sediment of Honghu Lake, Hubei, China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2006年第2期18卷 402-406页

作者： yao shu-chun XUE Bin XIA Wei-lan Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Graduate School of CAS Beijing 100039 China

Vertical profiles of the total organic carbon （TOC）, total nitrogen （TN）, phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, China. The average sedimentation rate was 1.55 mm/a. The results indicated that trophic status of Honghu Lake in the historical period had experienced three stages. Before 1840 the lake was characterized with lower productivity, TOC was less than 9.92 g/kg; TN was 0.902 to 1.24 g/kg. During about 1840-1950, population increased quickly, there was an obvious change in TOC with an average of 13.0 g/kg. Since 1950, human impacts have accelerated the lake eutrophication and nutrients enriched in the sediment with TOC of 21.7 to 93.1 g/kg, TN of 1.77 to 8.78 g/kg. The heavy metal concentration profiles presented similar distribution trends except Pb .and Mn. The results from elements analyses indicated that Honghu Lake had not been polluted by heavy metals except lead.

关键词： Honghu Lake lake deposit human impact

Pseudo-Magnetotelluric 2D Inversion Technology of Magnetic-Source Transient Electromagnetics

在线全文

学校读者我要写书评

暂无评论

Applied Geophysics 2020年第5期17卷 784-795,903页

作者： Han zi-qiang Jiang shu-ping Fengbing School of Civil Engineering Chongqing Jiaotong UniversityChongqing 400074China Gansu Transportation Planning Survey and Design Institute Co.Ltd. Lanzhou 730030China School of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

Based on the fact that it is diffi cult to implement optimum inversion using 2D and 3D forward modeling with magnetic-source transient electromagnetics(TEM),this paper explores a novel approach to the implementation of 2D magnetic-source TEM *** particular,we converted magnetic-source TEM data into magnetotelluric(MT)data and then used a 2D MT inversion method to implement a 2D magnetic-source TEM inversion ***,we studied the similarity between magnetic-source TEM waves and MT waves and between magnetic-source TEM all-time apparent resistivity and MT Cagniard apparent ***,we selected an optimal time-frequency transformation coeffi cient to implement rapid time-frequency transformation of all-time TEM apparent resistivity to MT Cagniard apparent ***,we conducted 1D pseudo-MT inversions of magnetic-source 1D TEM theoretical *** 1D inversion results demonstrated that the diff erence between the inversion parameters and model parameters was small,while the MT 1D inversion method could be used to conduct magnetic 1D TEM inversion within a certain margin of *** further conducted 2D pseudo-MT inversions of 3D magnetic-source TEM theoretical models,and the 2D inversion results indicated that selecting a joint 2D pseudo-MT transverse-electric(TE)and transverse-magnetic(TM)inversion method based on measuring the line above a 3D anomalous body can help to accurately implement a 2D inversion interpretation of the 3D TEM response.

关键词： TEM MT All-time apparent resistivity Time–frequency transformation 2D pseudo-MT inversion

Inguinal endometriosis: Ten case reports and review of literature

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2021年第36期9卷 11406-11418页

作者： shu-Hong Li Heng-zi Sun Wei-Hua Li shu-Zhen Wang Department of Obstetrics and Gynecology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

BACKGROUND To describe the characteristics,diagnosis and surgical treatment of inguinal endometriosis(IEM).CASE SUMMARY We retrospectively analyzed 10 patients diagnosed with IEM at Beijing Chao-Yang Hospital from 2011 to *** features,symptoms,images,surgical treatment,hormonal therapy and follow-up were collected and discussed.A total of 10 cases of IEM diagnosed by surgery and pathology were characterized by a lesion on the right side(9/11);five patients had symptoms related to the menstrual cycle,and only 3 patients were clearly diagnosed before *** was of little assistance in confirming the diagnosis,but magnetic resonance imaging showed specific,high-intensity ***,most of the IEM lesions were located in the extraperitoneal ligament(10/11);nine patients had inguinal hernias(IH),five had concurrent or prior pelvic endometriosis,and four had *** clinical results from extensive resection were *** IEM is an extremely rare condition that can easily be misdiagnosed prior to surgery.A right IH may contribute to the formation of right-sided IEM,and extensive resection involving the round ligament and hernia sac is essential to prevent recurrence.

关键词： Inguinal endometriosis Clinical characteristics Imaging examination Pelvic endometriosis Treatment Case report