全文获取类型
收费全文 | 316篇 |
免费 | 10篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 42篇 |
金属工艺 | 5篇 |
机械仪表 | 1篇 |
建筑科学 | 10篇 |
矿业工程 | 1篇 |
能源动力 | 15篇 |
轻工业 | 27篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 27篇 |
一般工业技术 | 74篇 |
冶金工业 | 41篇 |
自动化技术 | 73篇 |
出版年
2023年 | 8篇 |
2022年 | 5篇 |
2021年 | 14篇 |
2020年 | 6篇 |
2019年 | 8篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 16篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 20篇 |
2012年 | 18篇 |
2011年 | 24篇 |
2010年 | 12篇 |
2009年 | 17篇 |
2008年 | 13篇 |
2007年 | 17篇 |
2006年 | 15篇 |
2005年 | 14篇 |
2004年 | 13篇 |
2003年 | 5篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有326条查询结果,搜索用时 17 毫秒
111.
Effect of Internal Current Flow During the Sintering of Zirconium Diboride by Field Assisted Sintering Technology 下载免费PDF全文
Jesus Gonzalez–Julian Kevin Jähnert Kerstin Speer Limeng Liu Jan Räthel Michael Knapp Helmut Ehrenberg Martin Bram Olivier Guillon 《Journal of the American Ceramic Society》2016,99(1):35-42
Effect of electric current on sintering behavior and microstructure evolution of zirconium diboride (ZrB2) was investigated using three different configurations of Field Assisted Sintering Technology/Spark Plasma Sintering. The current flow through the ZrB2 compact was controlled by modifying the interface between the graphite punches and the electrical conductive powder. Boron nitride discs, graphite foils or direct contact with the graphite punches were the three different interfaces used in order to deflect, conduct or promote, respectively, the current during the sintering process of the electrically conductive ZrB2 ceramics. The current flow during the sintering process triggered the elimination/reduction in B2O3, leading to faster diffusion rates at high temperatures and limiting the formation of B4C secondary phase. This allows to control the final density, grain size (from 19.6 to 43.2 μm) and secondary phase formation (from 5.95 to 11.61 vol%) as well as the electrical resistivity (from 7.7 to 9.4 μΩ·cm) of the specimens. 相似文献
112.
The impact of differences in dough transient gluten network on gluten cross-linking during baking is insufficiently understood. We varied dough mixing times and/or added sodium stearoyl lactylate (SSL; 1.0% on flour dry matter basis) to the recipe and studied the effect on subsequent gluten polymerization during heating. The level of proteins extractable in sodium dodecyl sulfate containing media was fitted using first order kinetics. The extent and rate of gluten polymerization were lower when mixing for 8 min than when mixing for 2 min. This effect was even more outspoken in the presence of SSL. The present observations were explained as resulting from less gliadin incorporation in the polymer gluten network and from interaction of SSL with the gluten proteins. Finally, a higher degree of gluten polymerization during baking increased the firmness of the baked products. 相似文献
113.
The different routes for power production from biomass often lead to an intermediary product such as a synthesis gas or syngas, which is typically rich in hydrogen and carbon monoxide. The simple design, fuel flexibility and size, which often matches the amount of waste energy available in industrial sites, makes microturbines an attractive solution for on-site, decentralized power generation using a limited range of alternative fuels such as synthetic gas. The properties of the synthetic fuel differ from properties of natural gas and a detailed experimental study with a separated microturbine-like pressurized combustor is therefore necessary. The present article reviews the experimental results obtained by gradually switching the fuel feed from natural gas to wet syngas in a pressurized, slightly modified lean premix microturbine combustor. Temperature profiles, pressure, emissions and flame imaging were closely monitored to detect possible problems in operability of the combustor caused by the strong difference in fuel characteristics. 相似文献
114.
H. Schiefer M. Bram H. P. Buchkremer D. Stöver 《Journal of materials science. Materials in medicine》2009,20(8):1763-1770
Due to its good biocompatibility, porous titanium is an interesting material for biomedical applications. Bone tissue can
grow inside the porous structure and maintain a long and stable connection between the implant and the human bone. To investigate
its long term stability, the mechanical behavior of porous titanium was tested under static and dynamic conditions and was
compared to human bone tissue. A promising application of this material is the coating of dental implants. A manufacturing
technique was developed and implants were produced. These implants were fatigue tested according to modified ISO 14801 and
the micro structural change was examined. The fatigue test was statically modeled using finite element analysis (FEA). The
results show that the implants resist a continuous load which is comparable to the loading conditions in the human jaw. The
experiments show that the porous titanium has bone-like mechanical properties. Additionally the porous titanium shows an anisotropic
behavior of its mechanical properties depending on the alignment of the pores. Finally, other potential applications of porous
titanium are outlined. 相似文献
115.
Bram L.H.M. Sperber Henk A. Schols Martien A. Cohen Stuart Willem Norde Alphons G.J. Voragen 《Food Hydrocolloids》2009
The complex formation between β-lactoglobulin (β-lg) and pectin is studied using pectins with different physicochemical characteristics. Pectin allows for the control of both the overall charge by degree of methyl-esterification as well as local charge density by the degree of blockiness. Varying local charge density, at equal overall charge is a parameter that is not available for synthetic polymers and is of key importance in the complex formation between oppositely charged (bio)polymers. LMP is a pectin with a high overall charge and high local charge density; HMPB and HMPR are pectins with a low overall charge, but a high and low local charge density, respectively. Dynamic light scattering (DLS) titrations identified pHc, the pH where soluble complexes of β-lg and pectin are formed and pH?, the pH of phase separation, both as a function of ionic strength. pHc decreased with increasing ionic strength for all pectins and was used in a theoretical model that showed local charge density of the pectin to control the onset of complex formation. pH? passed through a maximum with increasing ionic strength for LMP because of shielding of repulsive interactions between β-lg molecules bound to LMP, while attractive interactions were repressed at higher ionic strength. Potentiometric titrations of homo-molecular solutions and mixtures of β-lg and pectin showed charge regulation in β-lg–pectin complexes. Around pH 5.5–5.0 the pKas of β-lg ionic groups are increased to induce positive charge on the β-lg molecule; around pH 4.5–3.5 the pKa values of the pectin ionic groups are lowered to retain negative charge on the pectin. Since pectins with high local charge density form complexes with β-lg at higher ionic strength than pectins with low local charge density, pectin with a high local charge density is preferred in food systems where complex formation between protein and pectin is desired. 相似文献
116.
Griskevicius Vladas; Tybur Joshua M.; Van den Bergh Bram 《Canadian Metallurgical Quarterly》2010,98(3):392
Why do people purchase proenvironmental “green” products? We argue that buying such products can be construed as altruistic, since green products often cost more and are of lower quality than their conventional counterparts, but green goods benefit the environment for everyone. Because biologists have observed that altruism might function as a “costly signal” associated with status, we examined in 3 experiments how status motives influenced desire for green products. Activating status motives led people to choose green products over more luxurious nongreen products. Supporting the notion that altruism signals one’s willingness and ability to incur costs for others’ benefit, status motives increased desire for green products when shopping in public (but not private) and when green products cost more (but not less) than nongreen products. Findings suggest that status competition can be used to promote proenvironmental behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
118.
Bram van der Vlist Gerrit Niezen Stefan Rapp Jun Hu Loe Feijs 《Personal and Ubiquitous Computing》2013,17(4):783-799
In the transition from a device-oriented paradigm toward a more task-oriented paradigm with increased interoperability, people are struggling with inappropriate user interfaces, competing standards, technical incompatibilities, and other difficulties. The current handles for users to explore, make, and break connections between devices seem to disappear in overly complex menu structures displayed on small screens. This paper tackles the problem of establishing connections between devices in a smart home environment, by introducing an interaction model that we call semantic connections. Two prototypes are demonstrated that introduce both a tangible and an augmented reality approach toward exploring, making, and breaking connections. In the augmented reality approach, connections between real-world objects are visualized by displaying visible lines and icons from a mobile device containing a pico projector. In the tangible approach, objects in the environment are tagged and can be scanned and interacted with, to explore connection possibilities, and manipulate the connections. We discuss the technical implementation of a pilot study setup used to evaluate both our interaction approaches. We conclude the paper with the results of a user study that shows how the interaction approaches influence the mental models users construct after interacting with our setup. 相似文献
119.
V. J. de Waal T. M. Klapwijk P. van den Hamer 《Journal of Low Temperature Physics》1983,53(3-4):287-312
We report on the fabrication and performance of low-noise, all-niobium, thin-film planar dc SQUIDs with submicrometer Josephson junctions. The junctions are evaporated obliquely through a metal shadow evaporation mask, which is made using optical lithography with 0.5 µm tolerance. The Josephson junction barrier is formed by evaporating a thin silicon film and with a subsequent oxidation in a glow discharge. The junction parameters can be reproduced within a factor of two. Typical critical currents of the SQUIDs are about 3 µA and the resistances are about 100 Ω. With SQUIDs having an inductance of 1 nH the voltage modulation is at least 60 µV. An intrinsic energy resolution of 4×10?32 J/Hz has been reached. The SQUIDs are coupled to wire-wound input coils or with thin-film input coils. The thin-film input coil consists of a niobium spiral of 20 turns on a separate substrate. In both cases the coil is glued onto a 2-nH SQUID with a coupling efficiency of at least 0.5. Referred to the thin-film input coil, the best coupled energy resolution achieved is 1.2×10?30 J/Hz measured in a flux-locked loop at frequencies above 10 Hz. As far as we know, this is the best figure achieved with an all-refractory-metal thin-film SQUID. The fabrication technique used is suited for making circuits with SQUID and pickup coil on the same substrate. We describe a compact, planar, first-order gradiometer integrated with a SQUID on a single substrate. The gradient noise of this device is 3×10?12 T m?1. The gradiometer has a size of 12 mm×17 mm, is simple to fabricate, and is suitable for biomedical applications. 相似文献
120.