全文获取类型
收费全文 | 616篇 |
免费 | 21篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 148篇 |
金属工艺 | 10篇 |
机械仪表 | 6篇 |
建筑科学 | 33篇 |
矿业工程 | 3篇 |
能源动力 | 25篇 |
轻工业 | 56篇 |
水利工程 | 7篇 |
石油天然气 | 1篇 |
无线电 | 31篇 |
一般工业技术 | 118篇 |
冶金工业 | 107篇 |
原子能技术 | 5篇 |
自动化技术 | 84篇 |
出版年
2023年 | 3篇 |
2022年 | 13篇 |
2021年 | 16篇 |
2020年 | 5篇 |
2019年 | 8篇 |
2018年 | 14篇 |
2017年 | 13篇 |
2016年 | 14篇 |
2015年 | 15篇 |
2014年 | 22篇 |
2013年 | 35篇 |
2012年 | 29篇 |
2011年 | 38篇 |
2010年 | 34篇 |
2009年 | 33篇 |
2008年 | 36篇 |
2007年 | 24篇 |
2006年 | 18篇 |
2005年 | 9篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 13篇 |
2001年 | 14篇 |
2000年 | 17篇 |
1999年 | 8篇 |
1998年 | 45篇 |
1997年 | 34篇 |
1996年 | 19篇 |
1995年 | 15篇 |
1994年 | 6篇 |
1993年 | 11篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 9篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 7篇 |
1982年 | 1篇 |
1980年 | 4篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有637条查询结果,搜索用时 78 毫秒
121.
J. Nieto G. de Arcas M. Ruiz J. Vega J.M. López E. Barrera R. Castro N. Utzel P. Makijarvi L. Zabeo 《Fusion Engineering and Design》2012,87(12):2152-2155
EURATOM/CIEMAT and the Technical University of Madrid UPM are involved in the development of a FPSC (fast plant system control) prototype for ITER based on PXIe form factor. The FPSC architecture includes a GPU-based real time high performance computing service which has been integrated under EPICS (experimental physics and industrial control system). In this work we present the design of this service and its performance evaluation with respect to other solutions based in multi-core processors. Plasma pre-processing algorithms, illustrative of the type of tasks that could be required for both control and diagnostics, are used during the performance evaluation. 相似文献
122.
Timpano G Tabarani G Anderluh M Invernizzi D Vasile F Potenza D Nieto PM Rojo J Fieschi F Bernardi A 《Chembiochem : a European journal of chemical biology》2008,9(12):1921-1930
The dendritic cell-specific intercellular adhesion molecule (ICAM) 3-grabbing nonintegrin (DC-SIGN) is a C-type lectin that appears to perform several different functions. Besides mediating adhesion between dendritic cells and T lymphocytes, DC-SIGN recognizes several pathogens some of which, including HIV, appear to exploit it to invade host organisms. The intriguing diversity of the roles attributed to DC-SIGN and their therapeutic implications have stimulated the search for new ligands that could be used as biological probes and possibly as lead compounds for drug development. The natural ligands of DC-SIGN consist of mannose oligosaccharides or fucose-containing Lewis-type determinants. Using the known 3D structure of the Lewis-x trisaccharide, we have identified some monovalent alpha-fucosylamides that bind to DC-SIGN with inhibitory constants 0.4-0.5 mM, as determined by SPR, and have characterized their interaction with the protein by STD NMR spectroscopy. This work establishes for the first time alpha-fucosylamides as functional mimics of chemically and enzymatically unstable alpha-fucosides and describes interesting candidates for the preparation of multivalent systems able to block the receptor DC-SIGN with high affinity and with potential biomedical applications. 相似文献
123.
Recently, great effort has been devoted to obtain porous materials with customized pore size distribution, high surface area and submicrometer sized microstructures or nanostructures. In this work, the viability of colloidal processing routes to obtain porous bulk ceramics using alumina nanopowders and d-fructose as a dispersant and a porosity former has been explored.The rheological behaviour of nanosuspensions was studied in order to assure their stability and to analyse the influence of different parameters (solids loading, fructose content, pH, sonication time). Mesoporous green bodies were obtained by slip casting with d-fructose in concentrations ranging from 5 to 50 wt%. The drying and burning-out conditions were determined by DTA-TG measurements and the sintering cycles were selected from the dynamic sintering curve. Sintered alumina materials with high porosity (>60%), open microstructures, submicrometer sized porosity (dp = 140–210 nm) and grain size lower than 500 nm, were obtained for pieces sintered at temperatures of 1300 and 1400 °C. The influence of different processing parameters on the porosity and the microstructure of the sintered materials is discussed. 相似文献
124.
Briggs K Cases M Heard DJ Pastor M Pognan F Sanz F Schwab CH Steger-Hartmann T Sutter A Watson DK Wichard JD 《International journal of molecular sciences》2012,13(3):3820-3846
There is a widespread awareness that the wealth of preclinical toxicity data that the pharmaceutical industry has generated in recent decades is not exploited as efficiently as it could be. Enhanced data availability for compound comparison ("read-across"), or for data mining to build predictive tools, should lead to a more efficient drug development process and contribute to the reduction of animal use (3Rs principle). In order to achieve these goals, a consortium approach, grouping numbers of relevant partners, is required. The eTOX ("electronic toxicity") consortium represents such a project and is a public-private partnership within the framework of the European Innovative Medicines Initiative (IMI). The project aims at the development of in silico prediction systems for organ and in vivo toxicity. The backbone of the project will be a database consisting of preclinical toxicity data for drug compounds or candidates extracted from previously unpublished, legacy reports from thirteen European and European operation-based pharmaceutical companies. The database will be enhanced by incorporation of publically available, high quality toxicology data. Seven academic institutes and five small-to-medium size enterprises (SMEs) contribute with their expertise in data gathering, database curation, data mining, chemoinformatics and predictive systems development. The outcome of the project will be a predictive system contributing to early potential hazard identification and risk assessment during the drug development process. The concept and strategy of the eTOX project is described here, together with current achievements and future deliverables. 相似文献
125.
Bescós R Rodríguez FA Iglesias X Knechtle B Benítez A Marina M Padullés JM Torrado P Vazquez J Rosemann T 《Journal of the International Society of Sports Nutrition》2012,9(1):3
Background
Information about behavior of energy intake in ultra-endurance cyclists during a 24-hour team relay race is scarce. The nutritional strategy during such an event is an important factor which athletes should plan carefully before the race. The purpose of this study was to examine and compare the nutritional intake of ultra-endurance cyclists during a 24-hour team relay race with the current nutritional guidelines for endurance events. Additionally, we analyzed the relationship among the nutritional and performance variables. 相似文献126.
The effects of gender and castration of females (IF, intact females; CF, castrated females; CM, castrated males) on performance and carcass and meat quality were studied in crossbred pigs (Landrace × Large White dams × Duroc sires) slaughtered at 119.2 (experiment 1) or 131.6 (experiment 2) kg body weight. Intact females had better feed conversion and less carcass fat than CF and CM. Trimmed shoulder yield was higher for CM than for CF with IF being intermediate. Primal cut yield and meat quality were similar for all treatments. Proportion of linoleic acid in backfat was lower in CF than in IF or CM and the differences were significant when pigs were slaughtered at 131.6 kg. The higher fat content and the fatty acid profile favor the use of castrated females and males over intact females for the production of heavy pigs destined to the dry-cured industry. 相似文献
127.
N. Habtu J. Font A. Fortuny C. Bengoa A. Fabregat P. Haure A. Ayude F. Stüber 《Chemical engineering science》2011,(14):3358
Heat transfer was investigated in an insulated packed bed column with co-current downflow of gas and liquid under constant and periodically modulated gas–liquid feed temperature. Bed temperatures at three axial positions were assessed at steady state for different insulating systems, different gas and liquid flow rates and system pressure. The experimental profiles recorded were modeled with a dynamic pseudo-homogeneous one parameter model to analyze the effect of operating conditions and to deduce coefficients of overall (U) and bed to wall (hW) heat transfer. It appears that the heat transfer is strongly affected by the system pressure, whereas the liquid flow rate has a smaller influence. The experimental data of hW were correlated with the operating conditions leading to a small average error of 7% in the correlation. Condensation of water vapor occurring in the column seems to contribute to the heat transfer inside the packed bed. Several dynamic experiments modulating the feed temperature were also conducted and described with the help of the dynamic model. Predictions with the fitted values of U were in good agreement with experiments and give confidence to apply this model in the investigation of the catalytic wet air oxidation of phenol over carbon conducted in a trickle bed reactor under temperature feed modulation. 相似文献
128.
129.
Ferran Roig‐Roig Conxita Solans Jordi Esquena María José García‐Celma 《应用聚合物科学杂志》2013,130(2):1377-1382
Hyaluronic acid (HA) is a natural polysaccharide that is widely distributed in the human body. Its physicochemical properties and high biocompatibility make it a good candidate for biomedical and pharmaceutical uses. In the present work, we report HA‐based hydrogels that could be applied as drug delivery systems or as implants for the treatment of joint diseases. We use butanediol diglycidyl ether as a chemical crosslinker to obtain HA hydrogels. Using a new dissolution tester and ketoprofen (KP) as a model drug, we study the release properties of the hydrogels. We obtain homogeneous and transparent hydrogels with high strength and elasticity. The swelling ratio (SR) depends on the crosslinker concentration and pH of the medium. We also reveal differences between the release profile of KP from swollen and unswollen hydrogels. The characteristics and differences in KP release profiles depending on the SR suggest the possibility of obtaining controlled release from HA‐based hydrogels. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1377‐1382, 2013 相似文献
130.
James Padfield Matthew D. Ferran Audrey Lao Linmei 《Journal of Energetic Materials》2013,31(2):106-116
The effects of the addition of ethyl centralite, a commonly used stabilizer in double-base propellants, on a cyclotrimethylenetrinitramine (RDX)-based polymer-bonded explosive (PBX) were investigated. A reduction in sensitivity to impact was observed with increasing ethyl centralite content along with a reduction in explosiveness. Small-scale gap tests also show a reduction in sensitivity to shock initiation. High-performance liquid chromatography (HPLC) analysis of impact-stressed samples showed traces of 4-nitro- and 2-nitro-ethyl centralite and N-ethyl-N-nitrosoaniline; these results indicate the possibility that the mechanism of desensitization may, at least partially, be chemical in nature. 相似文献