全文获取类型
收费全文 | 362篇 |
免费 | 7篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 46篇 |
金属工艺 | 2篇 |
机械仪表 | 12篇 |
建筑科学 | 8篇 |
矿业工程 | 1篇 |
能源动力 | 5篇 |
轻工业 | 26篇 |
水利工程 | 3篇 |
无线电 | 59篇 |
一般工业技术 | 54篇 |
冶金工业 | 103篇 |
原子能技术 | 4篇 |
自动化技术 | 41篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 4篇 |
2018年 | 4篇 |
2017年 | 2篇 |
2016年 | 6篇 |
2015年 | 7篇 |
2014年 | 4篇 |
2013年 | 17篇 |
2012年 | 5篇 |
2011年 | 17篇 |
2010年 | 7篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 15篇 |
2006年 | 12篇 |
2005年 | 9篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 9篇 |
2000年 | 12篇 |
1999年 | 9篇 |
1998年 | 42篇 |
1997年 | 26篇 |
1996年 | 13篇 |
1995年 | 16篇 |
1994年 | 3篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1974年 | 5篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1965年 | 3篇 |
1957年 | 2篇 |
1956年 | 1篇 |
1955年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有369条查询结果,搜索用时 109 毫秒
1.
Kotiadis S. Zimmer A. Elsayed A. Vandersluis E. Ravindran C. 《Metallurgical and Materials Transactions A》2020,51(8):4195-4214
Metallurgical and Materials Transactions A - Aluminum alloys with transition metals Fe and Ni show potential to form the basis for castable alloys with high electrical and thermal conductivity for... 相似文献
2.
Beim Abbau von Braunkohle kann die Oxidation von im Sediment vorhandenen Pyriten zu einer Versauerung des Sickerwassers führen und damit zu einer Mobilisierung von Schwermetallen. Um den Oxidationsgrad der Pyrite in der unbehandelten Abraumkippe eines Braunkohletagebaus abzuschätzen, wurden am Lehrstuhl für Angewandte Geologie der Ruhr-Universität Bochum neben umfangreichen Felduntersuchungen und Laborversuchen auch numerische Simulationsrechnungen durchgeführt. Um die in einem Tagebau oxidierten Pyritmengen zu berechnen, wurde mithilfe des numerischen Modells gw-chem.f sowohl die Oxidation auf der Abbauseite als auch die Oxidation auf der Kippenseite berechnet. Die genaue Kenntnis der umgesetzten Pyritmenge ist notwendig, um die Kalkmenge zu ermitteln, die benötigt wird, um die bei der Pyritoxidation entstehende Schwefelsäure zu neutralisieren. Dadurch soll das Grundwasser geschützt werden, wenn der Tagebau wieder geflutet wird. 相似文献
3.
Experimental investigation and numerical simulation of liquid supported stretch blow molding 下载免费PDF全文
An innovative production process for PET bottles ad containers is analyzed in this article. Liquid Bi‐Orientation (LBO) is a liquid supported stretch blow molding (SBM), which combines the separate blowing and filling phases of conventional SBM. The process modification is mainly characterized by forming the bottle using the desired liquid product instead of pressurized air. Consequently, possible improvements evolve regarding production cycle time, energy consumption and machine footprint. To make use of these capabilities, comprehensive process understanding is required, which can be increased using numerical simulation methods. Therefore, in this article, an LBO process model is set‐up and experimentally evaluated. The model explicitly considers the fluid‐structure interaction between liquid and PET, which significantly influences the PET forming behavior. The key simulation parameters namely the strong rate and temperature dependency of PET and a realistic process parameter determination are also included. The model is evaluated using two different methods to show the reliability of the process prediction. POLYM. ENG. SCI., 55:933–944, 2015. © 2014 Society of Plastics Engineers 相似文献
4.
Beata Olejnik Anna Jarz?b Ewa M. Kratz Mariusz Zimmer Andrzej Gamian Miros?awa Ferens-Sieczkowska 《International journal of molecular sciences》2015,16(7):14933-14950
The impact of seminal plasma components on the fertilization outcomes in humans is still under question. The increasing number of couples facing problems with conception raises the need for predictive biomarkers. Detailed understanding of the molecular mechanisms accompanying fertilization remains another challenge. Carbohydrate–protein recognition may be of key importance in this complex field. In this study, we analyzed the unique glycosylation pattern of seminal plasma proteins, the display of high-mannose and hybrid-type oligosaccharides, by means of their reactivity with mannose-specific Galanthus nivalis lectin. Normozoospermic infertile subjects presented decreased amounts of lectin-reactive glycoepitopes compared to fertile donors and infertile patients with abnormal semen parameters. Glycoproteins containing unveiled mannose were isolated in affinity chromatography, and 17 glycoproteins were identified in liquid chromatography-tandem mass spectrometry with electrospray ionization. The N-glycome of the isolated glycoproteins was examined in matrix-assisted laser desorption ionization mass spectrometry. Eleven out of 27 identified oligosaccharides expressed terminal mannose residues, responsible for lectin binding. We suggest that lowered content of high-mannose and hybrid type glycans in normozoospermic infertile patients may be associated with impaired sperm protection from preterm capacitation and should be considered in the search for new infertility markers. 相似文献
5.
It is well known in socio-economics that the success of an innovation process depends to a great extent on public acceptance. The German HyTrust project analyzes the current state of public acceptance in hydrogen technology in the mobility sector. This paper focuses on cutting-edge results of interviews, focus groups and a representative survey. Based on these results, almost 80% of the Germans are in favor of introducing hydrogen vehicles. But from the perspective of the general public, it is important that hydrogen is produced in an environmentally friendly way. HyTrust is the socio-scientific research project that accompanies the German Federal Government's National Innovation Programme. 相似文献
6.
Nano design for macroscopic coatings – new application potentials by PVD coatings up to 100 μm thickness Non-homogeneous coatings still limit the application of thicker layers due to defect growth and irregular layer thickness distribution along the surface of complex shaped components. Therefore, the layer thickness is usually limited to about 10 μm. In order to limit the surface roughness by the growing layer, multilayer coating systems are deposited by highly ionized plasmas. This allows significantly smoother layers to be produced, which until now could only be produced by mechanical finishing. Furthermore, by combining selected material systems and targeted parameter selection, structures can be deposited during coating, especially on edges, which result in a reduction of the cutting edge radius. In future, edge geometries should therefore be able to be specifically adjusted through the coating process. 相似文献
7.
S. Ghosh B. Grandchamp G.A. Koné F. Marc C. Maneux T. Zimmer V. Nodjiadjim M. Riet J.-Y. Dupuy J. Godin 《Microelectronics Reliability》2011,51(9-11):1736-1741
The reliability of InP/InGaAs DHBT under high collector current densities and low junction temperatures is analyzed and modeled. From the Gummel characteristics, we observe several types of device degradation, resulting from the long term changes of base and collector current in both lower and higher base–emitter voltage ranges which impacts the reduction of DC current gain. In this paper, we investigate the underlying physical mechanism of base and collector current degradation with the help of TCAD device simulation. We chose the HICUM model level2 for the modeling purpose to evaluate the drift of model parameters according to stress time. The evolution of the model parameters is described with suitable equations to achieve a physics based compact electrical aging model. The aging laws and the parameter evolution equations with stress time are implemented in compact electrical aging model which allows us to simulate the impact of device failure mechanisms on the circuit in operating conditions. 相似文献
8.
Roland Oltra Alexandre Zimmer Claire Sorriano Fabien Rechou Céline Borkowski Olivier Néel 《Electrochimica acta》2011,(20):7038
Some constituent intermetallic (IMPs) particles at the surface of aluminium alloys are considered as preferential sites for the initiation of structural corrosion resulting in localized trenching around the particles and the surrounding Al matrix. In this work, a modified scanning electrochemical microscope (SECM) experiment was used to induce such phenomena via a local alcalinisation on 200 nm thick aluminium coatings promoting their local dissolution in an aerated 0.1 M NaCl electrolyte. The local alcalinisation was induced by the oxygen reduction reaction on the tip of a SECM which mimics the surface of an isolated IMP. From a phenomenological point of view, reproducible cylindrical damage develops in front of the platinum ultramicroelectrode (UME). Using a 2D finite element modelling to simulate the SECM experiments, the role of the local alcalinisation was validated and the calculated Al dissolution rate was found in agreement with the experimental evaluation. 相似文献
9.
In this paper, we address the problem of localizing extrema points and iso-contours of ambient environmental fields (specifically,
ocean bottom landscape and underwater plumes) using a networked formation of autonomous underwater vehicles. We propose the
use of the Nelder-Mead extension to the basic simplex nonlinear optimization algorithm. In these robust gradient-free strategies,
decisions are solely made based on field values measured by the individual vehicles, while measurements are fused and actions
decided according to the algorithm. A main goal of this paper is to trigger interest in direct search methods as pertains
to this type of robotic problem. 相似文献
10.
Michael Breuß Henning Zimmer Joachim Weickert 《Journal of Mathematical Imaging and Vision》2011,39(3):230-244
Optic flow and stereo reconstruction are important examples of correspondence problems in computer vision. Correspondence
problems have been studied for almost 30 years, and energy-based methods such as variational approaches have become popular
for solving this task. However, despite the long history of research in this field, only little attention has been paid to
the numerical approximation of derivatives that naturally occur in variational approaches. 相似文献