全文获取类型
收费全文 | 350篇 |
免费 | 17篇 |
专业分类
电工技术 | 6篇 |
综合类 | 1篇 |
化学工业 | 103篇 |
金属工艺 | 11篇 |
机械仪表 | 4篇 |
建筑科学 | 6篇 |
矿业工程 | 1篇 |
能源动力 | 5篇 |
轻工业 | 18篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 31篇 |
一般工业技术 | 78篇 |
冶金工业 | 40篇 |
原子能技术 | 5篇 |
自动化技术 | 54篇 |
出版年
2022年 | 5篇 |
2021年 | 14篇 |
2020年 | 9篇 |
2019年 | 9篇 |
2018年 | 11篇 |
2017年 | 12篇 |
2016年 | 9篇 |
2015年 | 3篇 |
2014年 | 13篇 |
2013年 | 26篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 15篇 |
2009年 | 13篇 |
2008年 | 14篇 |
2007年 | 11篇 |
2006年 | 12篇 |
2005年 | 14篇 |
2004年 | 14篇 |
2003年 | 6篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 10篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1961年 | 2篇 |
排序方式: 共有367条查询结果,搜索用时 15 毫秒
11.
Acyl Migration Kinetics of Vegetable Oil 1,2-Diacylglycerols 总被引:1,自引:0,他引:1
Joseph A. Laszlo David L. Compton Karl E. Vermillion 《Journal of the American Oil Chemists' Society》2008,85(4):307-312
The acyl migration kinetics of long-chain 1,2-diacylglycerol (1,2-DAG) to form 1,3-diacylglycerol (1,3-DAG) over the temperature
range of 25–80 °C were examined using 1H-NMR spectroscopy. Lipase-catalyzed ethanolysis of high-oleic sunflower oil, followed by a series of solvent extraction steps,
generated high purity 1,2-DAG (0.93 mol fraction of the DAG content). The 1,2-DAG mole fraction of 0.32 at equilibrium was
found to be insensitive to temperature, indicating that long-chain acyl group migration is neither endothermic nor exothermic.
Determination of the temperature-dependent, first-order reaction kinetic parameters revealed a 1,2-DAG half life (t
1/2) of 3,425 h and 15.8 h at 25 and 80 °C, respectively. A comparison of 1,2-DAG with 2-monoacylglycerol indicated that there
is no difference between the two in the potential energy state (ΔG
‡) of their respective transitions states or cyclic intermediates.
Product names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may
be suitable. 相似文献
12.
Research on dynamic micro-deformation under laser point source 总被引:2,自引:0,他引:2
X.F. Wang G.N. Chen Sh.G. Hu J. Takacs Gy. Krallics Y.P. Su 《International Journal of Machine Tools and Manufacture》2005,45(12-13):1515-1522
The dynamic micro-deformation of the specimen under laser point source is measured using a laser beam reflex amplifier system and numerically simulated by Msc.Marc software. Compared with experimental result and calculated result, the final deformation direction of the specimen depends on the result of the thermal strain and the phase transformation strain cooperation, away from the laser beam or towards the laser beam, the final deformation angle depends on temperature gradient in the thickness direction and the geometry constraint of the specimen. The conclusion lays the foundation for further research on the mechanism of laser bending. At the same time, it is proposed that the model of calculation based on classical Fourier heat transfer theory cannot be enough to simulate the dynamic micro-deformation of the specimen under laser point source, the model of calculation should be modified in the future. 相似文献
13.
Amir Mohammadzadeh Pter P. Lakatos Mihly Balogh Ferenc Zdor Dvid rpd Kardi Zoltn S. Zdori Kornl Kirly Anna Rita Galambos Szilvia Barsi Pl Riba Sndor Benyhe Lszl Kles Tams Tbi va Szk Laszlo G. Harsing Jr. Mahmoud Al-Khrasani 《International journal of molecular sciences》2021,22(5)
The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP. 相似文献
14.
15.
J.S. Brown C.W. Band E.C. Finch R.A. Holt H.A. Klein J. Laursen A.F. McClelland N.J. Peacock J.D. Silver M.F. Stamp J. Takacs 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,9(4):682-685
This work describes the application of the technique of photographic VUV spectroscopy to accurate measurement of the wavelength of the theoretically interesting 1s2s 3S1-1s2p 3P2 transition in helium-like Ne8+ in a recoil ion source. Good resolution is obtained, and a preliminary value of 124.815±0.002 nm is found for the wavelength. 相似文献
16.
Andreas Håkansson Laszlo Fuchs Fredrik Innings Johan Revstedt Christian Trägårdh Björn Bergenståhl 《Chemical engineering science》2011,66(8):1790
Particle image velocimetry is performed on a model of a high pressure homogenizer, scaled for qualitative similarity of the one phase turbulent flow field in a production scale homogenizer. Flow fields in gap entrance, gap and gap outlet chamber are obtained with high resolution. The measurements show gap flow development and formation of a turbulent wall adherent jet when exiting into the outlet chamber. Turbulent kinetic energy spectra show how the turbulent energy available for fragmentation is transported over distance along the jet centre axis.The high resolution images are also used together with a Kolmogorov–Hinze theory framework for discussing drop fragmentation together with a direct evaluation of disruptive stresses from measurements. For the turbulent inertial mechanism large drops experience high fragmenting force close to eight gap heights downstream of the gap exit whereas this occurs closer to 20 gap heights for smaller drops. The turbulent viscous mechanism is most efficient at a downstream distance of eight gap heights into the outlet chamber for all drops sizes. 相似文献
17.
18.
Yessica Saez Laszlo B. Kish Robert Mingesz Zoltan Gingl Claes G. Granqvist 《Journal of Computational Electronics》2014,13(1):271-277
We classify and analyze bit errors in the current measurement mode of the Kirchhoff-law–Johnson-noise (KLJN) key distribution. The error probability decays exponentially with increasing bit exchange period and fixed bandwidth, which is similar to the error probability decay in the voltage measurement mode. We also analyze the combination of voltage and current modes for error removal. In this combination method, the error probability is still an exponential function that decays with the duration of the bit exchange period, but it has superior fidelity to the former schemes. 相似文献
19.
Quantum Information Processing - Historically, the information efficiency of the secret key in quantum key distribution (QKD) schemes based on binary signal formats was limited to 1 bit/particle.... 相似文献
20.
To produce high stressed automotive components like engine frames and cylinder heads in foundry industry often AlSi7Mg alloys are used. During mould filling and casting melt flow affects the development of the microstructure, which defines the mechanical properties. In this paper the microstructure formation in AlSi7Mg0.3 and AlSi7Mg0.6 alloys during directional solidification is investigated. To induce a forced melt flow a rotating magnetic field is applied. For that purpose a Bridgman‐type gradient furnace is equipped with a rotary ring magnet. For detailed investigation of the shape of the solid‐liquid interface and the primary dendrite spacing a decanting device is used. As a result, the forced melt flow substantially changes the dendritic solidification microstructure. The rotating magnetic field generates a radial secondary flow in and ahead of the mushy zone, which causes an enrichment of eutectics in the centre of the samples. At lower solidification velocities this locally leads to the transition to mixed columnar‐equiaxed or even to equiaxed growth. In that case the solid‐liquid interfaces of the decanted samples show a significant depression in the centre part. In the out‐of‐centre region columnar growth still exists and the primary dendrite spacing decreases with increasing melt flow. 相似文献