全文获取类型
收费全文 | 610篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 98篇 |
金属工艺 | 9篇 |
机械仪表 | 12篇 |
建筑科学 | 18篇 |
矿业工程 | 7篇 |
能源动力 | 9篇 |
轻工业 | 36篇 |
水利工程 | 1篇 |
无线电 | 64篇 |
一般工业技术 | 86篇 |
冶金工业 | 224篇 |
原子能技术 | 11篇 |
自动化技术 | 44篇 |
出版年
2016年 | 8篇 |
2015年 | 7篇 |
2014年 | 8篇 |
2013年 | 27篇 |
2012年 | 10篇 |
2011年 | 19篇 |
2010年 | 11篇 |
2009年 | 16篇 |
2008年 | 15篇 |
2007年 | 13篇 |
2006年 | 16篇 |
2005年 | 15篇 |
2004年 | 11篇 |
2003年 | 13篇 |
2002年 | 7篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 13篇 |
1998年 | 58篇 |
1997年 | 49篇 |
1996年 | 22篇 |
1995年 | 15篇 |
1994年 | 12篇 |
1993年 | 13篇 |
1992年 | 11篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 9篇 |
1986年 | 12篇 |
1985年 | 9篇 |
1984年 | 11篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 9篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 10篇 |
1974年 | 6篇 |
1973年 | 6篇 |
1971年 | 4篇 |
1970年 | 6篇 |
1960年 | 4篇 |
1957年 | 5篇 |
1955年 | 4篇 |
1954年 | 5篇 |
1948年 | 5篇 |
排序方式: 共有622条查询结果,搜索用时 500 毫秒
101.
JF Money-Kyrle F Bates J Ready BG Gazzard RH Phillips FC Boag 《Canadian Metallurgical Quarterly》1993,5(6):367-371
We report a non-randomized Phase II clinical trial to assess the efficacy and safety of liposomal daunorubicin (DaunoXome) in the treatment of AIDS related Kaposi's sarcoma. Eleven homosexual men with advanced Kaposi's sarcoma were entered in the trial. Changes in size, colour and associated oedema of selected 'target' lesions were measured. Clinical, biochemical and haematological toxicities were assessed. Ten subjects were evaluated. A partial response was achieved in four, of whom two subsequently relapsed. Stabilization of Kaposi's sarcoma occurred in the remaining six, maintained until the end of the trial period in four. The drug was generally well tolerated, with few mild symptoms of toxicity. The main problem encountered was haematological toxicity, with three subjects experiencing severe neutropenia (neutrophil count < 0.5 x 10(9)/l). There was no evidence of cardiotoxicity. In this small patient sample, liposomal daunorubicin was an effective and well tolerated agent in the treatment of Kaposi's sarcoma. 相似文献
102.
Clayton W. Bates Kim F. Nelson S. Atiq Raza John B. Mooney Jutta M. Recktenwald Loren Macintosh Robert Lamoreaux 《Thin solid films》1982,88(3):279-283
Thin films (about 1 μm) of CuInSe2 were prepared by spray pyrolysis. The component ratios in the spray solutions and the glass substrate temperature were varied in order to produce films of the desired stoichiometry and the importance of this starting ratio is demonstrated. The optimum spray conditions were suggested by thermodynamical calculations using a free energy minimization computer program applied to the Cu-In-Se system. Optical absorption studies of the films verified the existence of the proper compound.Heat treatments of the films were performed in order to produce conductivities and crystal structures for photovoltaic applications and are discussed in detail. In particular for CuInSe2 which gives the sphalerite structure under most spray conditions, a short heat treatment of a film with a starting Cu:In:Se ratio of 1.1:1:4 for 10 min at temperatures of 600, 500 and 400°C is described, which produces the chalcopyrite structure. 相似文献
103.
Calabrese V Bates TE Mancuso C Cornelius C Ventimiglia B Cambria MT Di Renzo L De Lorenzo A Dinkova-Kostova AT 《Molecular nutrition & food research》2008,52(9):1062-1073
Free radicals play a main pathogenic role in several human diseases such as neurodegenerative disorders, diabetes, and cancer. Although there has been progress in treatment of these diseases, the development of important side effects may complicate the therapeutic course. Curcumin, a well known spice commonly used in India to make foods colored and flavored, is also used in traditional medicine to treat mild or moderate human diseases. In the recent years, a growing body of literature has unraveled the antioxidant, anticarcinogenic, and antinfectious activity of curcumin based on the ability of this compound to regulate a number of cellular signal transduction pathways. These promising data obtained in vitro are now being translated to the clinic and more than ten clinical trials are currently ongoing worldwide. This review outlines the biological activities of curcumin and discusses its potential use in the prevention and treatment of human diseases. 相似文献
104.
A.J. Bates M.A. Sutherland F. Chapple S.K. Dowling A.P. Johnson B. Saldias J. Singh 《Journal of dairy science》2019,102(3):2492-2506
Anesthesia of the horn bud for calf disbudding commonly is attained by injection of local anesthetic over branches of the cornual nerve, with anesthesia achieved in 3 to 20 min. With experienced and trained staff, this method is effective in 88 to 100% of calves. Variability in response and time of onset can compromise calf welfare if calves are disbudded before anesthesia is attained. Proposed legislative reliance on effective local anesthetic as the minimal method of pain relief for calves at disbudding means that administration of local anesthetic must achieve a repeatable level and rapid onset of analgesia. We describe an alternative method of local anesthesia administration that uses local site infiltration of anesthetic over the horn bud. However, this method has not yet been scientifically validated. This study assessed differences between disbudding using the cornual nerve block and disbudding with local anesthesia administered by local site infiltration. Efficacy of local anesthesia was assessed at 30-s intervals after administration by absence of reaction to 3 consecutive needle pricks over the horn buds. Behavior indicating pain was assessed during disbudding and scored from 0 to 3. Calf behavior was also recorded for 3 h after disbudding. Accelerometer data loggers were fitted to each calf for 24 h before and after disbudding to assess lying and standing times. Median time to cutaneous desensitization for local infiltration was 60 s compared with 225 s for cornual nerve block, and the variance in time to desensitization was less with local infiltration. Calves disbudded under cornual block had a larger behavioral response (indicated by a graded aversive body reaction) than calves disbudded under local infiltration. A multivariable model predicted that the mean body reaction score would be 0.6 for calves disbudded under local infiltration and 1.2 for calves disbudded under cornual block. There was no difference in any behaviors between the treatment groups in the 3 h after disbudding. Method of analgesia had no effect on lying time over the 24 h after disbudding. In this study, local infiltration was at least as effective in providing analgesia for disbudding as the cornual nerve block. Our results suggest that a more consistent, effective level of analgesia during disbudding was achieved using local infiltration and that there was no difference in postoperative expressions of pain. 相似文献
105.
106.
Alex Bates Santanu Mukherjee Nicholas Schuppert Byungrak Son Joo Gon Kim Sam Park 《国际能源研究杂志》2015,39(11):1505-1518
The goal of the work presented here was to develop a simulation approach for studying the effects of materials and geometry on the performance of Li‐ion Solid State Batteries (SSB). Simulation provides the opportunity to explore, with ease, different material properties and cell geometries to optimize a Li‐ion SSB's performance. Simulations shown in this paper are time‐dependent and consider electrochemical reaction, heat transfer, the diffusion of Li‐ions and electrons in the electrolyte, and solid Li diffusion in the positive electrode. A 2D model was simulated and the results shown. The simulations were able to show discharge curves, heat flux, the concentration of Li‐ions, electrons, and solid Li at any time in the discharge cycle. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
107.
D J Bates 《BT Technology Journal》1997,15(3):158-168
This paper describes the top-level integration strategy for delivering the Card Services Platform (CSP), formerly known as Cashless Services Replacement System (CSRS), probably the largest successful integration by a single BT team to date. This paper explains the need for such a strategy to evolve, leading to significant efficiency improvements. It identifies the need for the careful management of integration testing of the complex interfaces involved in a system comprised of over 40 large computer systems, spread across the country. It shows how potential operational difficulties can be identified in the system testing phase and eradicated before impacting the product in a live situation. It outlines testing techniques, test coverage, granularity of test results and measure of goodness of the tested product. 相似文献
108.
Steam‐air blown bubbling fluidized bed biomass gasification (BFBBG): Multi‐scale models and experimental validation 下载免费PDF全文
Richard B. Bates Ahmed F. Ghoniem Whitney S. Jablonski Daniel L. Carpenter Christos Altantzis Aaron Garg John L. Barton Ran Chen Randall P. Field 《American Institute of Chemical Engineers》2017,63(5):1543-1565
During fluidized bed biomass gasification, complex gas‐solid mixing patterns and numerous chemical and physical phenomena make identification of optimal operating conditions challenging. In this work, a parametric experimental campaign was carried out alongside the development of a coupled reactor network model which successfully integrates the individually validated sub‐models to predict steady‐state reactor performance metrics and outputs. The experiments utilized an integrated gasification system consisting of an externally‐heated, bench‐scale, 4‐in., 5 kWth, fluidized bed steam/air blown gasifier fed with woody biomass equipped with a molecular beam mass spectrometer to directly measure tar species. The operating temperature (750–850°C) and air/fuel equivalence ratio (ER = 0–0.157) were independently varied to isolate their effects. Elevating temperature is shown to improve the char gasification rate and reduce tar concentrations. Air strongly impacts the composition of tar, accelerating the conversion of lighter polycyclic‐aromatic hydrocarbons into soot precursors, while also improving the overall carbon conversion. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1543–1565, 2017 相似文献
109.
L Canevari A Console EA Tendi JB Clark TE Bates 《Canadian Metallurgical Quarterly》1999,817(1-2):241-245
In order to test the effect of hypothermia on mitochondrial function damage following cerebral ischaemia/reperfusion, Mongolian gerbils were submitted to 30 min bilateral carotid occlusion and 2 h of reperfusion at 37 degreesC or 30 degreesC. After normothermic (37 degreesC) ischaemia/reperfusion, significant decreases in mitochondrial state 3 (+ADP) oxygen consumption (-42.2%), complex II-III activity in synaptosomes (-31.7%) and complex IV were measured, in both free mitochondria and synaptosomes (-30.3% and -27. 8% respectively). However, following hypothermic (30 degreesC) reperfusion, both respiration rates and all enzyme activities remained at levels not significantly different from those in the sham operated controls. 相似文献
110.
Applying global cost-benefit analysis methods to indoor air pollution mitigation interventions in Nepal,Kenya and Sudan: Insights and challenges 总被引:1,自引:0,他引:1
Indoor air pollution from burning solid fuels for cooking is a major environmental health problem in developing countries, predominantly affecting children and women. Traditional household energy practices also contribute to substantial time loss and drudgery among households. While effective interventions exist, levels of investment to date have been very low, in part due to lack of evidence on economic viability. Between 2004 and 2007, different combinations of interventions – improved stoves, smoke hoods and a switch to liquefied petroleum gas – were implemented in poor communities in Nepal, Sudan and Kenya. The impacts were extensively evaluated and provided the basis for a household-level cost-benefit analysis, which essentially followed the methodology proposed by the World Health Organization. The results suggest that interventions are justified on economic grounds with estimated internal rates of return of 19%, 429% and 62% in Nepal, Kenya and Sudan, respectively. Time savings constituted by far the most important benefit followed by fuel cost savings; direct health improvements were a small component of the overall benefit. This paper describes the methodology applied, discusses the findings and highlights the methodological challenges that arise when a global approach is applied to a local programme. 相似文献