全文获取类型
收费全文 | 798篇 |
免费 | 31篇 |
专业分类
电工技术 | 19篇 |
综合类 | 1篇 |
化学工业 | 166篇 |
金属工艺 | 6篇 |
机械仪表 | 13篇 |
建筑科学 | 46篇 |
矿业工程 | 1篇 |
能源动力 | 17篇 |
轻工业 | 62篇 |
水利工程 | 2篇 |
无线电 | 86篇 |
一般工业技术 | 131篇 |
冶金工业 | 129篇 |
原子能技术 | 7篇 |
自动化技术 | 143篇 |
出版年
2023年 | 9篇 |
2022年 | 4篇 |
2021年 | 13篇 |
2020年 | 8篇 |
2019年 | 10篇 |
2018年 | 13篇 |
2017年 | 12篇 |
2016年 | 20篇 |
2015年 | 19篇 |
2014年 | 24篇 |
2013年 | 39篇 |
2012年 | 28篇 |
2011年 | 38篇 |
2010年 | 39篇 |
2009年 | 40篇 |
2008年 | 25篇 |
2007年 | 34篇 |
2006年 | 27篇 |
2005年 | 31篇 |
2004年 | 30篇 |
2003年 | 26篇 |
2002年 | 30篇 |
2001年 | 17篇 |
2000年 | 16篇 |
1999年 | 14篇 |
1998年 | 34篇 |
1997年 | 30篇 |
1996年 | 20篇 |
1995年 | 16篇 |
1994年 | 13篇 |
1993年 | 25篇 |
1992年 | 18篇 |
1991年 | 10篇 |
1990年 | 7篇 |
1989年 | 12篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 10篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1981年 | 8篇 |
1980年 | 4篇 |
1978年 | 4篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1967年 | 2篇 |
1965年 | 2篇 |
排序方式: 共有829条查询结果,搜索用时 375 毫秒
41.
Bioavailability Studies and in vitro Profiling of the Selective Excitatory Amino Acid Transporter Subtype 1 (EAAT1) Inhibitor UCPH‐102 下载免费PDF全文
Dr. Isabell Haym Dr. Tri H. V. Huynh Dr. Stinne W. Hansen Dr. Martin H. F. Pedersen Dr. Josep A. Ruiz Dr. Mette N. Erichsen Dr. Mikko Gynther Walden E. Bjørn‐Yoshimoto Dr. Bjarke Abrahamsen Dr. Jesper F. Bastlund Dr. Christoffer Bundgaard Anette L. Eriksen Prof. Anders A. Jensen Prof. Lennart Bunch 《ChemMedChem》2016,11(4):403-419
Although the selective excitatory amino acid transporter subtype 1 (EAAT1) inhibitor UCPH‐101 has become a standard pharmacological tool compound for in vitro and ex vivo studies in the EAAT research field, its inability to penetrate the blood–brain barrier makes it unsuitable for in vivo studies. In the present study, per os (p.o.) administration (40 mg kg?1) of the closely related analogue UCPH‐102 in rats yielded respective plasma and brain concentrations of 10.5 and 6.67 μm after 1 h. Three analogue series were designed and synthesized to improve the bioavailability profile of UCPH‐102, but none displayed substantially improved properties in this respect. In vitro profiling of UCPH‐102 (10 μm ) at 51 central nervous system targets in radioligand binding assays strongly suggests that the compound is completely selective for EAAT1. Finally, in a rodent locomotor model, p.o. administration of UCPH‐102 (20 mg kg?1) did not induce acute effects or any visible changes in behavior. 相似文献
42.
Cosmin Popescu Björn Täljsten Thomas Blanksvärd Lennart Elfgren 《Structure and Infrastructure Engineering》2019,15(7):912-924
Routine bridge inspections usually consist of visual observations. These inspections are time-consuming and subjective. There is a need to identify new inspection techniques for infrastructure that reduce traffic disturbance, and improve the efficiency and reliability of the acquired data. This study compared the performance of three different imaging technologies for the three-dimensional (3D) geometric modeling of existing structures: terrestrial laser scanning, close-range photogrammetry, and infrared scanning. Each technology was used to assess six existing concrete railway bridges. The technologies were compared in terms of geometric deviations, visualization capabilities, the level of the inspector’s experience, and degree of automation. The results suggest that all methods investigated can be used to create 3D models, however, with different level of completeness. Measurements such as span length, deck widths, etc. can be extracted with good accuracy. Although promising, a full off-site inspection is currently not feasible as some areas of the bridges were difficult to capture mainly due to restricted access and narrow spaces. Measurements based on terrestrial laser scanning were closer to the reality compared to photogrammetry and infrared scanning. The study indicates the no special training is needed for photogrammetry and infrared scanning to generate a 3D geometric model. 相似文献
43.
Dr. Lennart Brewitz Dr. Jos J. A. G. Kamps Dr. Petra Lukacik Claire Strain-Damerell Yilin Zhao Dr. Anthony Tumber Tika R. Malla Dr. Allen M. Orville Dr. Martin A. Walsh Prof. Dr. Christopher J. Schofield 《ChemMedChem》2022,17(9):e202200016
The two SARS-CoV-2 proteases, i. e. the main protease (Mpro) and the papain-like protease (PLpro), which hydrolyze the viral polypeptide chain giving functional non-structural proteins, are essential for viral replication and are medicinal chemistry targets. We report a high-throughput mass spectrometry (MS)-based assay which directly monitors PLpro catalysis in vitro. The assay was applied to investigate the effect of reported small-molecule PLpro inhibitors and selected Mpro inhibitors on PLpro catalysis. The results reveal that some, but not all, PLpro inhibitor potencies differ substantially from those obtained using fluorescence-based assays. Some substrate-competing Mpro inhibitors, notably PF-07321332 (nirmatrelvir) which is in clinical development, do not inhibit PLpro. Less selective Mpro inhibitors, e. g. auranofin, inhibit PLpro, highlighting the potential for dual PLpro/Mpro inhibition. MS-based PLpro assays, which are orthogonal to widely employed fluorescence-based assays, are of utility in validating inhibitor potencies, especially for inhibitors operating by non-covalent mechanisms. 相似文献
44.
Barry Haseltine Tor‐Ulf Weck Lars Meyer Rob van der Pluijm Oliver Dupont Christoph Alfes Wolfram Jaeger John Roberts Jonathan Silver Dirk Martens O. Pfeffermann Bastian Drewes Erhard Gunkler Jan Kubica Nebojsa Mojsilovic Erhard Gunkler Johann Marx Armin Ohler Hipolito Sousa Rui Sousa Romeu S. Vicente J. R. Mendes Silva Roberto Capozucca 《Mauerwerk》2011,15(6):348-361
45.
Stef KerkhofsHeiko Lipkens Firmin VelghePieter Verlooy Johan A. Martens 《Journal of food engineering》2011,106(1):35-39
Mayonnaise currently is produced using high shear stirrers. Here we present a new production method using a magnetic emulsification device. According to the new method a stable oil-in-water emulsion is formed by pumping the two immiscible liquids through a magnetohydrodynamic dispersion device consisting of a Venturi provided with an orthogonal permanent magnetic field. As a proof of concept, magnetically emulsified highly viscous mayonnaise was produced in a batch process and in a continuous process. The viscosity of the mayonnaise was significantly enhanced by applying the magnetic field. The oil droplet size distribution of mayonnaise produced using the magnetic emulsification method was similar to mayonnaise produced with conventional high shear mixers. In contrast to conventional processes no fast moving mixers were needed in this new mayonnaise production scheme. 相似文献
46.
Sotirios K. Goudos Margot Deruyck David Plets Luc Martens Wout Joseph 《Telecommunication Systems》2017,66(1):109-120
The power consumption of wireless access networks is an important issue. In this paper, the power consumption of Long Term Evolution (LTE) base stations is optimized. We consider the city of Ghent, Belgium with 75 possible LTE base station locations. We optimize the network towards two objectives: the coverage maximization and the power consumption minimization. We propose a new Barebones Self-adaptive Differential Evolution. The results of the proposed method indicate the advantages and applicability of our approach. 相似文献
47.
Un jet à très haute pression d'eau et d'air en même temps qu'une injection de pâte de ciment est en train de ?révolutionner? la pratique des injections dans le sol et consolidation des fondations. Cette technique développée en Suède est brièvement exposée ici. L'article s'appuie sur une note résumée publiée par le Conseil suédois pour la recherche sur la construction. 相似文献
48.
Michel Honselaar Guzay Pasaoglu Adwin Martens 《International Journal of Hydrogen Energy》2018,43(27):12278-12294
As of 2003, 15 hydrogen refuelling stations (HRSs) have been deployed in the Netherlands. To become established, the HRS has to go through a permitting procedure. An important document of the permitting dossier is the quantitative risk assessment (QRA) as it assesses the risks of the HRS associated to people and buildings in the vicinity of the HRS. In the Netherlands, a generic prescribed approach exists on how to perform a QRA, however specific guidelines for HRSs do not exist. An intercomparison among the QRAs of permitted HRSs has revealed significant inconsistencies on various aspects of the QRA: namely the inclusion of HRS sub-systems and components, the HRS sub-system and component considerations as predefined components, the application of failure scenarios, the determination of failure frequencies, the application of input parameters, the consideration of preventive and mitigation measures as well as information provided regarding the HRS surroundings and the societal risk. It is therefore recommended to develop specific QRA guidelines for HRSs. 相似文献
49.
Gordon B. Scarth G. O. Martens 《International Journal of Circuit Theory and Applications》1994,22(2):121-143
A new synthesis algorithm is presented for the realization of a doubly terminated complex lossless two-port from a given canonic set of scattering polynomials. the synthesis algorithm is based entirely on polynomial evaluations and thus polynomial arithmetic and routines for zero finding are not needed. the accuracy problem due to coefficient sensitivity is avoided. In particular, explicit knowledge of the intermediate polynomials is not required. the simplicity and functionality of the algorithm are based on a new representation of elementary sections given by a set of canonic parameters, namely the transmission zero of the section, the reflectance evaluated at the transmission zero and, for reciprocal sections, the return group delay evaluated at the transmission zero. A great deal of freedom is available, since transmission zeros with any multiplicity and located anywhere in the complex plane are realized independently. Also, complex networks composed exclusively of either inductors or capacitors as the dynamic elements are possible. an example is given to illustrate the robustness of the algorithm. 相似文献
50.