全文获取类型
收费全文 | 2081篇 |
免费 | 141篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 51篇 |
综合类 | 2篇 |
化学工业 | 377篇 |
金属工艺 | 75篇 |
机械仪表 | 28篇 |
建筑科学 | 79篇 |
矿业工程 | 4篇 |
能源动力 | 65篇 |
轻工业 | 161篇 |
水利工程 | 11篇 |
石油天然气 | 4篇 |
无线电 | 180篇 |
一般工业技术 | 465篇 |
冶金工业 | 435篇 |
原子能技术 | 11篇 |
自动化技术 | 278篇 |
出版年
2023年 | 37篇 |
2022年 | 47篇 |
2021年 | 78篇 |
2020年 | 54篇 |
2019年 | 59篇 |
2018年 | 60篇 |
2017年 | 47篇 |
2016年 | 79篇 |
2015年 | 70篇 |
2014年 | 75篇 |
2013年 | 122篇 |
2012年 | 139篇 |
2011年 | 184篇 |
2010年 | 126篇 |
2009年 | 98篇 |
2008年 | 112篇 |
2007年 | 107篇 |
2006年 | 86篇 |
2005年 | 61篇 |
2004年 | 50篇 |
2003年 | 41篇 |
2002年 | 31篇 |
2001年 | 23篇 |
2000年 | 21篇 |
1999年 | 18篇 |
1998年 | 55篇 |
1997年 | 34篇 |
1996年 | 35篇 |
1995年 | 29篇 |
1994年 | 15篇 |
1993年 | 14篇 |
1991年 | 9篇 |
1990年 | 11篇 |
1989年 | 16篇 |
1988年 | 8篇 |
1987年 | 19篇 |
1986年 | 15篇 |
1985年 | 18篇 |
1984年 | 11篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 8篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1975年 | 6篇 |
1973年 | 6篇 |
1972年 | 5篇 |
1969年 | 6篇 |
排序方式: 共有2226条查询结果,搜索用时 0 毫秒
101.
Integration of Emerging Biomedical Technologies in Meat Processing to Improve Meat Safety and Quality 下载免费PDF全文
Joshua T. Ravensdale Ranil Coorey Gary A. Dykes 《Comprehensive Reviews in Food Science and Food Safety》2018,17(3):615-632
Modern‐day processing of meat products involves a series of complex procedures designed to ensure the quality and safety of the meat for consumers. As the size of abattoirs increases, the logistical problems associated with large‐capacity animal processing can affect the sanitation of the facility and the meat products, potentially increasing transmission of infectious diseases. Additionally, spoilage of food from improper processing and storage increases the global economic and ecological burden of meat production. Advances in biomedical and materials science have allowed for the development of innovative new antibacterial technologies that have broad applications in the medical industry. Additionally, new approaches in tissue engineering and nondestructive cooling of biological specimens could significantly improve organ transplantation and tissue grafting. These same strategies may be even more effective in the preservation and protection of meat as animal carcasses are easier to manipulate and do not have the same stringent requirements of care as living patients. This review presents potential applications of emerging biomedical technologies in the food industry to improve meat safety and quality. Future research directions investigating these new technologies and their usefulness in the meat processing chain along with regulatory, logistical, and consumer perception issues will also be discussed. 相似文献
102.
Simon W. So Kendra M. Fleming Cayla M. Duffy Joshua P. Nixon David A. Bernlohr Tammy A. Butterick 《International journal of molecular sciences》2022,23(8)
The microglial fatty-acid-binding protein 4-uncoupling protein 2 (FABP4-UCP2) axis is a key regulator of neuroinflammation in high-fat-diet (HFD)-fed animals, indicating a role for FABP4 in brain immune response. We hypothesized that the FABP4-UCP2 axis is involved in regulating diet-induced cognitive decline. We tested cognitive function in mice lacking microglial FABP4 (AKO mice). Fifteen-week-old male AKO and wild-type (WT) mice were maintained on 60% HFD or normal chow (NC) for 12 weeks. Body composition was measured using EchoMRI. Locomotor activity, working memory, and spatial memory were assessed using behavioral tests (open field, T-maze, and Barnes maze, respectively). Hippocampal microgliosis was assessed via immunohistochemical staining. An inflammatory cytokine panel was assayed using hippocampal tissue. Real-time RT-PCR was performed to measure microglial UCP2 mRNA expression. Our data support that loss of FABP4 prevents cognitive decline in vivo. HFD-fed WT mice exhibited impaired long- and short-term memory, in contrast with HFD-fed AKO mice. HFD-fed WT mice had an increase in hippocampal inflammatory cytokine expression (IFNγ, IL-1β, IL-5, IL-6, KC/GRO(CXCL1), IL-10, and TNFα) and microgliosis, and decreased microglial UCP2 expression. HFD-fed AKO mice had decreased hippocampal inflammatory cytokine expression and microgliosis and increased microglial UCP2 expression compared to HFD-fed WT mice. Collectively, our work supports the idea that the FABP4-UCP2 axis represents a potential therapeutic target in preventing diet-induced cognitive decline. 相似文献
103.
The biogeography of pungency in three species of wild chili in the chaco and surrounding highland habitats of southeastern Bolivia is described. We report that Capsicum chacoense, C. baccatum, and C. eximium are polymorphic for production of capsaicin and its analogs, such that completely pungent and completely nonpungent individuals co-occur in some populations. In C. chacoense, the density of plants and the proportion of pungent plants increased with elevation. Above 900 m, all individuals in all populations except two were pungent; nonpungent individuals in at least one of the two polymorphic populations were likely a result of spreading by humans. The occurrence of pungent and nonpungent individuals in three species of ancestral Capsicum and the geographic variation of pungency within species suggest that production of capsaicin and its analogs entails both costs and benefits, which shift from one locality to another. Determining the selection pressures behind such shifts is necessary to understand the evolution of pungency in chilies. 相似文献
104.
提出了一种应用反应精馏隔壁塔把乙酸甲酯废液处理成乙酸正丁酯的新工艺流程,即采用反应精馏隔壁塔替代常规流程中的反应精馏塔及甲醇回收塔。利用Aspen Plus模拟软件对反应精馏隔壁塔及常规流程进行了模拟,考察了进料位置、反应段位置及高度、耦合位置等结构参数对反应精馏隔壁塔的影响,并在保证产品纯度的前提下对反应精馏隔壁塔进行了最优化分析。分析结果显示反应精馏隔壁塔可以节能17.34%,并能有效降低设备投资费用和操作费用。 相似文献
105.
Enthalpies of formation of compounds in Al-Ni-Y system 总被引:1,自引:0,他引:1
The enthalpies of formation of the ternary compounds Al4NiY, Al2NiY, Al2Ni6Y3, Al16 Ni3Y, AlNiY, Al3Ni2Y, AlNi8Y3, Al7Ni3Y2, and of the binary comp ounds Al2Y containing nickel and Ni5Y containing aluminum have been determined by high temperature reaction calorimetry. The enthalpy values measured are compared to previously published results where available as well as extended Miedema model predictions. The melting points of the compounds were determined by DTA and X-ray diffraction was used to confirm the crystal structures of the compounds. The enthalpi es of formation of the ternary compounds show a maximum along the 50%Al (mole fr action) section. The ternary compounds appear along lines of constant yttrium content consistent with binary compound solubility extensions. 相似文献
106.
Simon Rendel Ian Thompson Paul Gough Andrew Cherrill Joshua Pollard Ed Bennis 《Landscape Research》1997,22(2):225-235
Landscape Transformed
London, Academy Editions, 1996, 112 pp., no price given, ISBN 1-85490-452-3
Sculpting with the Environment: a natural dialogue
Baile Oakes (Ed.)
New York, Van Nostrand Reinhold, 1995, ISBN 0-442-01642-5, 252 pp., £45.00, hb.
After the Ruins: restoring the countryside of Northern France after the Great War
Hugh Clout
Exeter, University of Exeter Press, 1996, ISBN 0-85989-491-6,332 pp., £35.
Environmental Aesthetics: ideas, politics and planning
J. Douglas Porteous
London and New York, Routledge, 1996, ISBN 0-415-13769-1, 20 pp., £15.99.
Countryside Survey 1990 Main Report
C.J. Barr, R.G.H. Bunce, R.T. Clarke, R.M. Fuller, M.T. Furse, M.K. Gillespie, G.B. Groom, C.J. Hallam, M. Hornung, D.C. Howard & M.J. Ness
London, Department of the Environment, 1993, 174 pp., £12.00 (available from DoE Publications Sales Unit, Block 3, Spur 2, Government Buildings, Lime Grove, Eastcote, HA4 8SE)
World of Environmental Design, Volume 1: Urban Spaces I (Streets and Squares)
Francisco Asenio Cerver
Barcelona, Arco Editorial, 1995, 255 pp., US$75 (per volume) ISBN 84-8185-004-7 (complete work), ISBN 84-8185-005-5 (Volume 1)
'The Remains of Distant Times': archaeology and the National Trust
David Morgan Evans, Peter Salway & David Thackray (Eds)
Woodbridge, Suffolk, The Boydell Press, 1996, ISBN 0-85115-671-1, hb, 235 pp., £29.50
Apostle of Taste: Andrew Jackson Downing 1815-1852
D. Schuyler
Baltimore, fohns Hopkins University Press, 1996, ISBN 0-8018-5229-3, $35.95 相似文献
London, Academy Editions, 1996, 112 pp., no price given, ISBN 1-85490-452-3
Sculpting with the Environment: a natural dialogue
Baile Oakes (Ed.)
New York, Van Nostrand Reinhold, 1995, ISBN 0-442-01642-5, 252 pp., £45.00, hb.
After the Ruins: restoring the countryside of Northern France after the Great War
Hugh Clout
Exeter, University of Exeter Press, 1996, ISBN 0-85989-491-6,332 pp., £35.
Environmental Aesthetics: ideas, politics and planning
J. Douglas Porteous
London and New York, Routledge, 1996, ISBN 0-415-13769-1, 20 pp., £15.99.
Countryside Survey 1990 Main Report
C.J. Barr, R.G.H. Bunce, R.T. Clarke, R.M. Fuller, M.T. Furse, M.K. Gillespie, G.B. Groom, C.J. Hallam, M. Hornung, D.C. Howard & M.J. Ness
London, Department of the Environment, 1993, 174 pp., £12.00 (available from DoE Publications Sales Unit, Block 3, Spur 2, Government Buildings, Lime Grove, Eastcote, HA4 8SE)
World of Environmental Design, Volume 1: Urban Spaces I (Streets and Squares)
Francisco Asenio Cerver
Barcelona, Arco Editorial, 1995, 255 pp., US$75 (per volume) ISBN 84-8185-004-7 (complete work), ISBN 84-8185-005-5 (Volume 1)
'The Remains of Distant Times': archaeology and the National Trust
David Morgan Evans, Peter Salway & David Thackray (Eds)
Woodbridge, Suffolk, The Boydell Press, 1996, ISBN 0-85115-671-1, hb, 235 pp., £29.50
Apostle of Taste: Andrew Jackson Downing 1815-1852
D. Schuyler
Baltimore, fohns Hopkins University Press, 1996, ISBN 0-8018-5229-3, $35.95 相似文献
107.
Garrett Jones Tae Jin Lee Joshua Glass Grace Rountree Lane Ulrich Amy Estes Mary Sezer Wenbo Zhi Shruti Sharma Ashok Sharma 《International journal of molecular sciences》2022,23(4)
The tear film is a multi-layer fluid that covers the corneal and conjunctival epithelia of the eye and provides lubrication, nutrients, and protection from the outside environment. Tear fluid contains a high concentration of proteins and has thus been recognized as a potential source of biomarkers for ocular disorders due to its proximity to disease sites on the ocular surface and the non-invasive nature of its collection. This is particularly true in the case of dry eye disease, which directly impacts the tear film and its components. Proteomic analysis of tear fluid is challenging mainly due to the wide dynamic range of proteins and the small sample volumes. However, recent advancements in mass spectrometry have revolutionized the field of proteomics enabling unprecedented depth, speed, and accuracy, even with small sample volumes. In this study using the Orbitrap Fusion Tribrid mass spectrometer, we compared four different mass spectrometry workflows for the proteomic analysis of tear fluid collected via Schirmer strips. We were able to establish a method of in-strip protein digestion that identified >3000 proteins in human tear samples from 11 healthy subjects. Our method offers a significant improvement in the number of proteins identified compared to previously reported methods without pooling samples. 相似文献
108.
Wei Meng Joshua D. Palmer Michael Siedow Saikh Jaharul Haque Arnab Chakravarti 《International journal of molecular sciences》2022,23(4)
Gliomas represent a wide spectrum of brain tumors characterized by their high invasiveness, resistance to chemoradiotherapy, and both intratumoral and intertumoral heterogeneity. Recent advances in transomics studies revealed that enormous abnormalities exist in different biological layers of glioma cells, which include genetic/epigenetic alterations, RNA expressions, protein expression/modifications, and metabolic pathways, which provide opportunities for development of novel targeted therapeutic agents for gliomas. Metabolic reprogramming is one of the hallmarks of cancer cells, as well as one of the oldest fields in cancer biology research. Altered cancer cell metabolism not only provides energy and metabolites to support tumor growth, but also mediates the resistance of tumor cells to antitumor therapies. The interactions between cancer metabolism and DNA repair pathways, and the enhancement of radiotherapy sensitivity and assessment of radiation response by modulation of glioma metabolism are discussed herein. 相似文献
109.
110.
Swift Joshua K.; Callahan Jennifer L.; Heath Christopher J.; Herbert Gregory L.; Levine Jason C. 《Canadian Metallurgical Quarterly》2010,47(2):235
While previous research on deterioration has focused on identifying individuals at risk for negative outcomes, little is known about the nature or pattern by which deterioration occurs. The problem of deterioration is especially salient in training clinics; a setting in which higher deterioration rates have been reported. Two studies were designed to test the applicability of the phase model to deterioration in a training clinic and to replicate the model with a training clinic referral-base sample. In Study 1, the course of therapy was monitored for 135 clients. For the 38 clients who deteriorated during therapy, a model where increased symptoms (demediation) reliably preceded both decreased functioning (dehabilitation) and decreased well-being (demoralization) was found. In Study 2, the same three phases were prospectively monitored for 914 undergraduate students on a weekly basis throughout a single semester. For the 158 individuals who deteriorated during this time, a model where demediation reliably preceded dehabilitation, which preceded demoralization was found. These results have clinical implications for the use of tailored intervention strategies focusing on the deterioration phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献