全文获取类型
收费全文 | 330篇 |
免费 | 22篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 128篇 |
金属工艺 | 2篇 |
机械仪表 | 3篇 |
建筑科学 | 11篇 |
矿业工程 | 1篇 |
能源动力 | 6篇 |
轻工业 | 97篇 |
水利工程 | 1篇 |
无线电 | 16篇 |
一般工业技术 | 38篇 |
冶金工业 | 8篇 |
自动化技术 | 37篇 |
出版年
2023年 | 6篇 |
2022年 | 26篇 |
2021年 | 42篇 |
2020年 | 19篇 |
2019年 | 18篇 |
2018年 | 14篇 |
2017年 | 7篇 |
2016年 | 9篇 |
2015年 | 17篇 |
2014年 | 14篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 27篇 |
2010年 | 19篇 |
2009年 | 12篇 |
2008年 | 18篇 |
2007年 | 15篇 |
2006年 | 12篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2002年 | 3篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有354条查询结果,搜索用时 224 毫秒
41.
Maintenance of proper intracellular concentrations of monovalent cations, mainly sodium and potassium, is a requirement for survival of any cell. In the budding yeast Saccharomyces cerevisiae, monovalent cation homeostasis is determined by the active extrusion of protons through the Pma1 H+-ATPase (reviewed in another chapter of this issue), the influx and efflux of these cations through the plasma membrane transporters (reviewed in this chapter), and the sequestration of toxic cations into the vacuoles. Here, we will describe the structure, function, and regulation of the plasma membrane transporters Trk1, Trk2, Tok1, Nha1, and Ena1, which play a key role in maintaining physiological intracellular concentrations of Na+, K+, and H+, both under normal growth conditions and in response to stress. 相似文献
42.
Baesmat Hana Jannaty Bodson Marc 《International Journal of Control, Automation and Systems》2022,20(2):483-495
International Journal of Control, Automation and Systems - The paper proposes a complex domain control and robustness analysis approach to damping of Sub-Synchronous Control Interactions (SSCI) in... 相似文献
43.
44.
45.
Dziuba Szymon Cierniak-Emerych Anna Michalski Grzegorz Poulová Petra Mohelská Hana Klímová Blanka 《Universal Access in the Information Society》2021,20(1):171-178
Universal Access in the Information Society - It is generally accepted that it is young people who are particularly interested in information and communication technologies (ICT). Older adults... 相似文献
46.
Gossypol has been identified as a component of bract (FDB) from frost-killed, field-grown cotton by its chromatographic behavior
on films of silica and cellulose (four eluents and five methods of detection). In addition, a derivative of gossypol was detected,
and it was shown chromatographically that gossypol was removed from extracts of FDB by a divalent metal and by aniline. The
total gossypol content, by spectrophotometric determination of gossypol-aniline complex, of FDB was 0.93%, but for a sample
of bract from a cotton plant that had been grown in a hothouse it was only 0.048%. However the free gossypol contents in both
were similar (0.065% and 0.044%, respectively). Both bract samples were from glanded cotton varieties. It is worthwhile to
investigate the effect of gossypol on lung tissue to see if it can contribute to the acute response of byssinosis. In addition,
it is noted that the waste from ginned cotton which is sometimes used as livestock feed may contain gossypol. 相似文献
47.
Studenovská H Slouf M Rypácek F 《Journal of materials science. Materials in medicine》2008,19(2):615-621
The technique for fabrication of soft porous hydrogels, in which both the size and the orientation of inner pores can be controlled,
was developed. Three-dimensional hydrophilic gels based on poly[2-hydroxyethyl methacrylate] are designed as scaffolds for
regeneration of soft tissues, e.g., nerve tissue. Anisotropic macropores of the size ranging from 10 to 50 μm were formed
(1) by using a porogen-leaching method with a solid organic porogen, (2) by phase-separation during gelation in solvent-nonsolvent
mixture, or (3) by combination of solid porogen elimination and phase-separation. As a porogen, poly(l-lactide) fibers were applied and consequently washed away under mild conditions to obtain desired spatial orientation of
pores. Highly water-swollen polymer gels were characterized with high pressure (low vacuum) scanning electron microscopy (AquaSEM).
The morphology of voids remaining after removing the solid PLLA porogen (the macropores) was clearly shown. 相似文献
48.
Hana Sebestova Hana Chmelickova Libor Nozka Jiri Moudry 《Journal of Materials Engineering and Performance》2012,21(5):764-769
Laser welding is a high power density technology of materials joining that has many advantages in comparison with conventional
fusion welding methods, for example, high accuracy, flexibility, repeatability and especially very narrow heat-affected zone
which results in minimal workpiece distortions. Since it is still quite expensive technology, minimal spoilage is required.
Effective system of quality control and processing parameters optimization must be established to reduce total costs, which
is particularly required in industrial production. In this article some results of pulsed Nd:YAG laser welding process monitoring
based on the measurement of plasma electron temperature are presented. The ability of designed sensor to detect weld penetration
depth has been demonstrated. Plasma spectral lines intensities measurement can discover gap instabilities as well as local
sheet thickness reduction. 相似文献
49.
One of the most important issues in a liquid propellant rocket is to measure the amount of remaining liquid propellant under low gravity environment during space mission. This paper presents the results of experiment and analysis of a pressure–volume–temperature (PVT) method which is a gauging method for low gravity environment. The experiment is conducted using 7.4 l tank for liquid nitrogen with various liquid-fill levels. To maximize the accuracy of a PVT method with minimum hardware, the technique of a helium injection with low mass flow rate is applied to maintain stable temperature profile in the ullage volume. The PVT analysis considering both pressurant and cryogen as a binary mixture is suggested. At high liquid-fill levels of 72–80%, the accuracy from the conventional PVT analysis is within 4.6%. At low fill levels of 27–30%, the gauging error is within 3.4% by mixture analysis of a PVT method with specific low mass flow rate of a helium injection. It is concluded that the proper mass flow rate of a helium injection and PVT analyses are crucial to enhance the accuracy of the PVT method with regard to various liquid-fill levels. 相似文献
50.
Microribonucleic acids (miRNAs) have been linked with various regulatory functions and disorders, such as cancers and heart diseases. They, therefore, present an important target for detection technologies for future medical diagnostics. We report here a novel method for rapid and sensitive miRNA detection and quantitation using surface plasmon resonance (SPR) sensor technology and a DNA*RNA antibody-based assay. The approach takes advantage of a novel high-performance portable SPR sensor instrument for spectroscopy of surface plasmons based on a special diffraction grating called a surface plasmon coupler and disperser (SPRCD). The surface of the grating is functionalized with thiolated DNA oligonucleotides which specifically capture miRNA from a liquid sample without amplification. Subsequently, an antibody that recognizes DNA*RNA hybrids is introduced to bind to the DNA*RNA complex and enhance sensor response to the captured miRNA. This approach allows detection of miRNA in less than 30 min at concentrations down to 2 pM with an absolute amount at high attomoles. The methodology is evaluated for analysis of miRNA from mouse liver tissues and is found to yield results which agree well with those provided by the quantitative polymerase chain reaction (qPCR). 相似文献