检索结果-南通市图书馆

Industrial Experience with Case Hardening of Stainless Steels by Solution Nitriding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料热处理学报 2004年第5期25卷 354-359页

作者： hans Berns Bernd Edenhofer Roland Zaugg Ruhr University Materials Technology D-44780 Bochum GermanyIPSEN Industries International GmbH D-47514 Kleve GermanyHdrterei GersterA.G. CH-4622 Egerkingen Switzerland

SolNit(R) is a novel heat treatment to case harden stainless steels with nitrogen instead of carbon. The calculated equilibrium pressure of N2 corresponds well with the nitrogen content in the steel surface. The process is carried out in vacuum furnaces with pressurized gas quenching. Numerous parts of different stainless steels have been successfully SolNit(R) treated in industry leading to superior properties in respect to hardness/strength and corrosion

关键词：不锈钢渗氮表面硬化热处理

Recycling of automotive aluminum

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2057-2063页

作者： Jirang CUI hans J.ROVEN Department of Materials Science and Engineering Norwegian University of Science and Technology(NTNU)

With the global warming of concern,the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive because of its economic and environmental *** this work,recycling of automotive aluminum is reviewed to highlight environmental benefits of aluminum recycling,use of aluminum alloys in automotive applications,automotive recycling process,and new technologies in aluminum scrap *** survey shows that newly developed techniques such as laser induced breakdown spectroscopy(LIBS) and solid state recycling provide promising alternatives in aluminum scrap *** with conventional remelting and subsequent refinement,solid state recycling utilizing compression and extrusion at room or moderate temperature can result in significant energy savings and higher metal yield.

关键词： recycling automotive aluminum sorting mechanical separation solid state recycling

Hepatitis C virus core antigen testing: Role in diagnosis, disease monitoring and treatment

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第22期20卷 6701-6706页

作者： hans L Tillmann GI/Hepatology Duke Clinical Research Institute and Duke UniversityDurhamNC 27708United States

While hepatitis B virus(HBV)screening relies on hepatitis B surface antigen to confirm HBV infection since the early days of hepatitis B disease management,hepatitis C virus(HCV)infection screening is based on anti-HCV testing which does not discriminate active from past *** to confirm infection HCV RNA testing has been required;recently a HCV core antigen assay became widely commercially available which could serve to confirm *** assay is less sensitive than current HCV RNA assays,but as more than 50%of anti-HCV positive persons will be HCV core antigen positive,HCV core antigen testing can be a cost effective and reflex test to confirm HCV infection in anti-HCV positive individuals and will be easier as it can be applied on the same *** treatment monitoring,more data need to be generated,but the early data available at present suggest that HCV core antigen may be an alternative to HCV RNA *** direct antivirals,HCV core antigen could even be superior to HCV RNA testing,as direct antivirals might already prevent virus formation when HCV core antigen is still produced and thereby correlates better with eventual viral clearance.

关键词： Hepatitis C virus Hepatitis C Diagnostic assay Diagnostic accuracy Hepatitis C virus core antigen Treatment monitoring

Estimation of Pool Boiling Heat Transfer Coefficients of Ethanol-Water Mixtures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 1999年第2期7卷 95-103页

作者：谷俊杰 hans-JrgBart Lehrstuhl fur Thermische Verfahrenstechnik Universitat Kaiserslautern67653 KaiserslauternGermany

Based on the analysis of the principles of heat and mass transfer from the liquid bulk to bubble surface during nucleation, a new estimation method to predict the heat transfer of the nucleate pool boiling in binary mixtures is proposed in this paper by using the heat and mass transfer analogy (Colburn analogy) at the bubble surface transfer layers. With the use of Thome's concept of boiling range, an approximate method is derived to realize the calculation. The predicted results by this method are in good agreement with the experimental data from different sources.

关键词： heat transfer boiling water-ethanol mixture estimation

Colorectal carcinogenesis-update and perspectives

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第48期20卷 18151-18164页

作者： hans Raskov hans-Christian Pommergaard Jakob Burcharth Jacob Rosenberg Speciall?gecentret ved Diakonissestiftelsen 2000 Frederiksberg Denmark Department of Surgery Herlev Hospital University of Copenhagen DK-2730 Herlev Denmark

Colorectal cancer(CRC)is a very common malignancy in the Western World and despite advances in surgery,chemotherapy and screening,it is still the second leading cause of cancer deaths in this part of the *** factors are found important in the development of CRC including colonocyte metbolism,high risk luminal environment,inflammation,as well as lifestyle factors such as diet,tobacco,and alchohol *** recent years focus has turned towards the genetics and molecular biology of CRC and several interesting and promising correlations and pathways have been *** major genetic pathways of CRC are the Chromosome Instability Pathway representing the pathway of sporadic CRC through the K-ras,APC,and P53 mutations,and the Microsatellite Instability Pathway representing the pathway of he re di t ar y non-polyposis c olon c anc e r t hrough mutations in mismatch repair *** identify early cancers,screening programs have been initiated,and the leading strategy has been the use of faecal occult blood testing followed by colonoscopy in positive *** the treatment of colorectal cancer,significant advances have been made in the recent *** molecular targets of CRC include at least two important cell surface receptors:the epidermal growth factorreceptor and the vascular endothelial growth factor *** genetic and molecular knowledge of CRC has widen the scientific and clinical perspectives of diagnosing and ***,despite significant advances in the understanding and treatment of CRC,results from targeted therapy are still not *** studies will determine the role for this new treatment modality.

关键词： Colorectal carcinogenesis Risk factors Microbiology Genetics Diet Microbiome Inflammation

Low Energy Certificate——An exploration on optimization and evaluation of energy-efficient building envelope

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第6期54卷 1639-1644页

作者： ZHANG Hui hans-Peter LEIMER School of Architecture Southeast University Nanjing 210096 China Hochschule fuer angewandte Wissenschaft und Kunst Hildesheim 31134 Hildesheim Germany

Energy saving is the crucial task of green architecture,energy-saving design and evaluation should be *** Energy Certificate(LEC),an interactive computer program for energy efficiency and certification of building envelope,is briefly introduced in this paper in aspects of certification standards,procedure,methods *** the evaluation report of Innovation-pavilion PoI features,reference values of LEC are presented.

关键词： optimization and evaluation of energy efficiency Low Energy Certificate(LEC) energy performance of building enve-lope interactive

Activated Natural Killer Cells Hit Neurogenesis in the Aging Brain

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2021年第7期37卷 1072-1074页

作者： Angelica Cuapio hans-Gustaf Ljunggren Center of Infectious Medicine Department of Medicine HuddingeKarolinska Institutet14152 StockholmSweden

Why neurogenesis is attenuated in elderly individuals is an intriguing question that has raised renewed *** associated with declined neurogenesis in the aged brain have been attributed to inflammatory cytokines[1].More recently,a specific role for interferon-y(IFN-y)produced by CD8-expressing cytotoxic T cells has been implicated[2].These observations suggest a scenario in which neurogenesis,at least in part,is regulated by immune cells within the aging *** raises several interesting questions with regards to the characteristics of specific immune cells within the brain,the signals for their expansion and maintenance,and their role in affecting neurogenesis and cognition during normal brain aging.

关键词： interferon Killer attributed

Numerical analysis of hydroabrasion in a hydrocyclone

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 2016年第2期13卷 304-319页

作者： Mehdi Azimian hans-Jorg Bart Department of Mechanical and Process Engineering University of Kaiserslautern 67663 Kaiserslautern Germany

The velocity profiles and separation efficiency curves of a hydrocyclone were predicted by an Euler-Euler approach using a computational fluid dynamics tool ANSYS-CFX 14.5. The Euler-Euler approach is capable of considering the particle-particle interactions and is appropriate for highly laden liquid-solid mixtures. Pre- dicted results were compared and validated with experi- mental results and showed a considerably good agreement. An increase in the particle cut size with increasing solid concentration of the inlet mixture flow was observed and discussed. In addition to this, the erosion on hydrocyclone walls constructed from stainless steel 410, eroded by sand particles （mainly SiOz）, was predicted with the Euler-La- grange approach. In this approach, the abrasive solid particles were traced in a Lagrangian reference frame as discrete particles. The increases in the input flow velocity, solid concentration, and the particle size have increased the erosion at the upper part of the cylindrical body of the hydrocyclone, where the tangential inlet flow enters the hydrocyclone. The erosion density in the area between the cylindrical to conical body area, in comparison to other parts of the hydrocyclone, also increased considerably. Moreover, it was observed that an increase in the particle shape factor from 0.1 to 1.0 leads to a decrease of almost 70 % in the average erosion density of the hydrocyclone wall surfaces.

关键词： Hydrocyclone Computational fluiddynamicS (CFD) Separation efficiency - Erosion rateErosion impact parameters

Tree species richness enhances stand productivity while stand structure can have opposite effects, based on forest inventory data from Germany and the United States of America

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2018年第1期5卷 36-52页

作者： Laura Zeller Jingjing Liang hans Pretzsch Center of Life and Food Sciences Weihenstephan Technical University of MunichHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Division of Forestry and Natural Resources Davis College of AgricultureNatural Resources&DesignWest Virginia University340 Percival HallMorgantownWV 26506-6108USA

Background： in recent studies, mixed forests were found to be more productive than monocultures with everything else remaining the same. Methods： To find out if this productivity is caused by tree species richness, by a more heterogeneous stand structure or both, we analyzed the effects of forest structure and tree species richness on stand productivity, based on inventory data of temperate forests in the United States of America and Germany. Results： Having accounted for effects such as tree size and stand density, we found that：（I） tree species richness increased stand productivity in both countries while the effect of tree size heterogeneity on productivity was negative in Germany but positive in the USA; （11） productivity was highest at sites with an intermediate amount of precipitation; and （111） growth limitations due water scarcity or low temperature may enhance structural heterogeneity. Conclusions： In the context of forest ecosystem goods and services, as well as future sustainable forest resource management, the associated implications would be：

关键词： Big data Overyielding Tree size heterogeneity Tree species mixing Climate Biodiversity-productivityrelationship