全文获取类型
收费全文 | 744篇 |
免费 | 21篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 5篇 |
综合类 | 2篇 |
化学工业 | 91篇 |
金属工艺 | 25篇 |
机械仪表 | 35篇 |
建筑科学 | 29篇 |
矿业工程 | 3篇 |
能源动力 | 18篇 |
轻工业 | 28篇 |
水利工程 | 5篇 |
石油天然气 | 11篇 |
无线电 | 58篇 |
一般工业技术 | 122篇 |
冶金工业 | 256篇 |
原子能技术 | 13篇 |
自动化技术 | 68篇 |
出版年
2022年 | 10篇 |
2018年 | 9篇 |
2017年 | 9篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 15篇 |
2013年 | 44篇 |
2012年 | 21篇 |
2011年 | 26篇 |
2010年 | 12篇 |
2009年 | 14篇 |
2008年 | 21篇 |
2007年 | 15篇 |
2006年 | 19篇 |
2005年 | 19篇 |
2004年 | 17篇 |
2003年 | 17篇 |
2002年 | 16篇 |
2001年 | 9篇 |
2000年 | 15篇 |
1999年 | 13篇 |
1998年 | 27篇 |
1997年 | 15篇 |
1996年 | 16篇 |
1995年 | 16篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 17篇 |
1988年 | 9篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1984年 | 17篇 |
1982年 | 8篇 |
1980年 | 13篇 |
1979年 | 13篇 |
1977年 | 15篇 |
1976年 | 14篇 |
1975年 | 12篇 |
1974年 | 15篇 |
1973年 | 13篇 |
1972年 | 10篇 |
1971年 | 10篇 |
1970年 | 7篇 |
1969年 | 7篇 |
1964年 | 8篇 |
1961年 | 7篇 |
1956年 | 6篇 |
1955年 | 7篇 |
排序方式: 共有769条查询结果,搜索用时 15 毫秒
1.
Patrick R. Taylor Ph.D. Milton Manrique Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1996,48(6):43-45
Due to several inherent advantages, plasma processing technology may become a very useful tool in the production of new materials. An increasing research effort based on experimental as well as theoretical investigations has been invested in this area for the synthesis of advanced materials. In describing the thermal-plasma processing technique, this article employs examples from research at the Plasma Processing Laboratory at the University of Idaho. 相似文献
2.
Under carefully chosen conditions, solidification theory may be applied to solid-state transformations, and this has been
done here for composition-invariant diffusion transformations. The predictions of the modeling are compared with isovelocity
experiments in two iron systems, Fe-7.29 wt pct Cr and Fe-3.1 wt pct Ni. The ferrite to austenite phase transformation is
used to demonstrate that stabilization of a planar transformation front at absolute stability is the natural lower velocity
limit for a composition-invariant (massive) transformation. The results of the model, which includes nonequilibrium effects,
clearly show that steady-state plane-front growth leading to composition invariance can be obtained at various temperatures
depending on the growth velocity. In the lower velocity range, at the limit of absolute stability (of the order of 10 μm/s in the systems studied), the transformation interface moves under conditions of local equilibrium, and the temperature
corresponds to the lower solvus temperature. At higher velocity (of the order of the interface diffusion rate, which in these
systems is of the order of cm/s), the transformation is predicted to proceed at temperatures close to T
0. At even higher rates, atom attachment kinetic undercooling will decrease the transformation temperature with respect to
T
0. In some cases, this temperature might even drop below the lower solvus.
This article is based on a presentation made at the symposium entitled “The Mechanisms of the Massive Transformation,” a part
of the Fall 2000 TMS Meeting held October 16–19, 2000, in St. Louis, Missouri, under the auspices of the ASM Phase Transformations
Committee. 相似文献
3.
4.
5.
6.
S Dawson D Bennett SD Carter M Bennett J Meanger PC Turner MJ Carter I Milton RM Gaskell 《Canadian Metallurgical Quarterly》1994,56(2):133-143
Twelve specific pathogen-free cats were infected either by intra-articular inoculation or by contact exposure to one of two strains of feline calicivirus (FCV), either F65, a field strain originating from an outbreak of lameness in a group of cats, or a vaccine strain. Following either route of exposure, both strains induced signs typical of FCV infection including oral and nasal ulceration, conjunctivitis and ocular discharge. These signs were of equal severity for both virus strains, but overall, following either route of infection, F65 induced more severe disease than the vaccine strain, with marked pyrexia, lethargy and lameness. Vaccine virus only induced a relatively mild lameness following intra-articular inoculation. Gross pathological and histopathological lesions were seen in some of the joints, but again changes were more severe in the F65-exposed cats. Virus was isolated from both normal and affected joints from both groups of F65-exposed cats, and from a joint from each cat inoculated intra-articularly with vaccine virus. Mild transient lameness was also seen in one of two control cats inoculated intra-articularly, but no pathological changes were seen or virus isolated from joints. A cDNA probe used in RNA dot blot hybridisation experiments was found to be specific and more sensitive than virus isolation in detecting FCV in selected tissues. This may be useful in future studies on the pathogenesis of FCV disease and in studies on viral persistence in FCV carriers. 相似文献
7.
P Laharrague D Larrouy AM Fontanilles N Truel A Campfield R Tenenbaum J Galitzky JX Corberand L Pénicaud L Casteilla 《Canadian Metallurgical Quarterly》1998,12(9):747-752
Inhaled nitric oxide (iNO) has been shown to improve oxygenation in severe persistent pulmonary hypertension of the newborn (PPHN). However, PPHN is often associated with various lung diseases. Thus, response to iNO may depend upon the aetiology of neonatal acute respiratory failure. A total of 150 (29 preterm and 121 term) newborns with PPHN were prospectively enrolled on the basis of oxygenation index (OI) higher than 30 and 40, respectively. NO dosage was stepwise increased (10-80 ppm) during conventional mechanical or high-frequency oscillatory ventilation while monitoring the oxygenation. Effective dosages ranged from 5 to 20 ppm in the responders, whereas iNO levels were unsuccessfully increased up to 80 ppm in the nonresponders. Within 30 min of iNO therapy, OI was significantly reduced in either preterm neonates (51+/-21 vs 23+/-17, P < .0001) or term infants with idiopathic or acute respiratory distress syndrome (45+/-20 vs 20+/-17, P < .0001), 'idiopathic' PPHN (39+/-14 vs 14+/-9, P < .0001), and sepsis (55+/-25 vs 26+/-20, P < .0001) provided there was no associated refractory shock. Improvement in oxygenation was less significant and sustained (OI=41+/-16 vs 28+/-18, P < .001) in term neonates with meconium aspiration syndrome and much less (OI=58+/-25 vs 46+/-32, P < .01) in those with congenital diaphragmatic hernia. Only 21 of the 129 term newborns (16%) required extracorporeal membrane oxygenation (57% survival). Survival was significantly associated with the magnitude in the reduction in OI at 30 min of iNO therapy, a gestational age > or =34 weeks, and associated diagnosis other than congenital diaphragmatic hernia. Conclusion, iNO improves the oxygenation in most newborns with severe hypoxaemic respiratory failure including preterm neonates. However, response to iNO is disease-specific. Furthermore, iNO when combined with adequate alveolar recruitment and limited barotrauma using exogenous surfactant and HFOV may obviate the need for extracorporeal membrane oxygenation in many term infants. 相似文献
8.
Milton E. Rose 《Journal of scientific computing》1990,5(2):169-185
A compact finite-difference scheme to solve one-phase Stefan problems in one dimension is described. Numerical experiments indicate that the moving interface is obtained withO(t) accuracy when 3–4 iterations per time step are used to solve the nonlinear implicit scheme. The scheme can be adapted to ADI methods in higher dimensions. 相似文献
9.
Chengyun Yue J. Milton Harris Per-Erik Hellberg Karin Bergstrom 《Journal of the American Oil Chemists' Society》1996,73(7):841-845
A series of noncyclic acetal-linked cleavable surfactants were simply prepared by condensation of aldehydes with poly(ethylene
glycol) monomethyl ethers. All of the products were characterized by1H nuclear magnetic resonance. Their hydrophile-lipophile balance, surface tension, cloud point, critical micelle concentration,
and foam height were determined. Hydrolysis kinetic studies, followed by gas chromatography, showed that they had higher hydrolytic
reactivity in acidic solution than cyclic acetal-linked cleavable surfactants. 相似文献
10.
Milton J. Rosen 《Journal of the American Oil Chemists' Society》1972,49(5):293-297
Changes in the various structural units present in surfactants strongly affect the interfacial properties shown by these materials.
Such properties as surface tension reduction, micelle formation, wetting, foaming and defoaming, detergency, and dispersion
of solids all show marked changes with variations in both the hydrophilic and hydrophobic portions of the surfactant molecule,
reflecting the processes occurring on a molecular level. Changes in these properties caused by such factors as the length
and nature of the hydrophobic group, branching or unsaturation in the hydrophobic group, the nature of the hydrophilic group
and its position in the molecule, and the presence or absence of an ionic charge are described and explained in terms of the
molecular processes involved.
Presented at the AOCS Short Course, “Update on Detergents and Raw Materials,” Lake Placid, New York, June 1971. 相似文献