全文获取类型
收费全文 | 344篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 27篇 |
金属工艺 | 2篇 |
机械仪表 | 7篇 |
建筑科学 | 3篇 |
能源动力 | 3篇 |
轻工业 | 12篇 |
石油天然气 | 15篇 |
无线电 | 3篇 |
一般工业技术 | 28篇 |
冶金工业 | 232篇 |
自动化技术 | 11篇 |
出版年
2024年 | 3篇 |
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 5篇 |
2013年 | 16篇 |
2012年 | 6篇 |
2011年 | 8篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 82篇 |
1997年 | 34篇 |
1996年 | 30篇 |
1995年 | 20篇 |
1994年 | 12篇 |
1993年 | 12篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 7篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1977年 | 4篇 |
1976年 | 5篇 |
排序方式: 共有344条查询结果,搜索用时 15 毫秒
71.
72.
The expressions of cysteine dioxygenase (CDO) gene in the liver, lung, skeletal muscle, and kidney were studied by in situ hybridization with a cDNA probe from rat liver CDO under normal conditions. Significant expression of the CDO gene was detected in the liver, lung, and kidney, but not skeletal muscle. In the liver, the signal was confined to the cytoplasm of the hepatocytes. Furthermore, the signal was stronger in the periportal than that in the perivenous areas. In the lung, an intensive signal was found in the bronchiolar epithelium. As to the kidney, an intensive signal was observed in the distal convoluted tubules, while no signal was found in the proximal convultions. 相似文献
73.
74.
Generators of early cortical somatosensory evoked potentials (SEPs) still remain to be precisely localised. This gap in knowledge has often resulted in unclear and contrasting SEPs localisation in patients with focal hemispheric lesions. We recorded SEPs to median nerve stimulation in a patient with right frontal astrocytoma, using a 19-channel recording technique. After stimulation of the left median nerve, N20 amplitude was normal when recorded by the parietal electrode contralateral to the stimulation, while it was abnormally enhanced in traces obtained by the contralateral central electrode. The amplitude of the frontal P20 response was within normal limits. This finding suggests that two dipolar sources, tangential and radial to the scalp surface, respectively, contribute concomitantly to N20 generation. The possible location of the N20 radial source in area 3a is discussed. The P22 potential was also recorded with increased amplitude by the central electrode contralateral to the stimulation, while N30 amplitude was normal in frontal and central traces. We propose that the radial dipolar source of P22 response is independent from both N20 and N30 generators and can be located either in 3a or in area 4. This report illustrates the usefulness of multichannel recordings in diagnosing dysfunction of the sensorimotor cortex in focal cortical lesions. 相似文献
75.
76.
Abid Ali Hassaballah Emad Talib Hashim Iamir E. Maloka 《Petroleum Science and Technology》2003,21(11):1631-1639
The theory of gas transport is simply stated, but it is quite complex to express in equations that can be used directly to calculate viscosity. A correlation was developed to predict viscosity of natural gas (of different API gravities) function of temperature and pressure. This correlation depends only on API gravity of natural gas. The proposed correlation has been verified using data of about 246 data points, and it is shows significantly better correlation, with an average absolute error of 3.2%. 相似文献
77.
Mahamad Hakimi Ibrahim Wan Ramli Wan Daud Meor Zainal Meor Talib 《Drying Technology》2013,31(3-4):1103-1117
ABSTRACT The drying characteristics of a single oil palm kernel suspended in a drying tunnel is studied. Luikov's unsteady state simultaneous heat and mass transpon equations are proposed as the governing equations. The model is simulated using the explicit and modified implicit Crank Nicholson finite difference algorithms. The desorption isotherms of the kernel warj determined using an environmental chamber and the data generated was found to fit the Hasley's and Henderson's equations well. The mass diffusion coefficient was determined by using a distributed system parameter identification technique where a weighted least square criterion between model and experimental average moisture content and temperature profiles is optimized using the Lagrangian algorithm within the constraints of the governing equations. The simulated parameter estimated drying characteristics were found to be in good agreement with experimental values. 相似文献
78.
In this study, an improvement in the supercapacitive behavior of a symmetrical carbon-based supercapacitor is achieved by modifying the stainless steel current collector using platinum nanoparticles (PtNs). The PtNs are allowed to grow on the surface of the current collectors before they make contact with the surface of activated carbon electrode monoliths prepared from pre-carbonized rubber wood sawdust. All of the methods used in the present study, i.e., electrochemical impedance spectroscopy, cyclic voltammetry and galvanostatic charge–discharge tests provide consistent results, suggesting that the monolithic form of carbon electrodes and PtNs play a significant role in reducing the equivalent series resistance from 337 to 18 mΩ and to increase the specific capacitance from 108 to 151 F g−1. This change improves the specific energy from 2.5 to 3.3 Wh kg−1 and the specific power from 275 to 288 W kg−1, respectively. 相似文献
79.
Safa A. Al-Naimi Farah Talib Jasim Al-Sudani Essam K. Halabia 《Chemical Engineering Research and Design》2011,89(7):930-939
The hydrodynamics in a trickle bed reactor (TBR) in non-ambient conditions are studied for air-water and air-acetone (pure organic liquid of low surface tension) systems. A flow map experiments for air-water and air-acetone systems are performed in a pilot plant reactor of 0.05 m i.d. and 1.25 m height. It has been demonstrated from the experimental results that the pressure drop tends to increase with increasing superficial gas and liquid velocity and reactor pressure, while it tends to decrease with increasing bed temperature. The results also show that the dynamic liquid holdup increases with increasing liquid velocity and decreases with increasing superficial gas velocity, reactor pressure and bed temperature. The dynamic liquid holdup and pressure drop values are obviously higher than those measured for air-water system at the same fluid fluxes, reactor pressure and bed temperature due to the surface tension effects. For higher reactor pressure and temperature, the trickle to pulse transition boundary shifts towered higher superficial velocities of both gas and liquid. 相似文献
80.
Leishmania amazonensis (MHOM/BR/77/LTB0016) amastigotes were obtained from mouse cutaneous lesions and maintained in vitro for 48 hr at pH 4.6, 33 C. These organisms were reproducing, capable of transformation to promastigotes, and did not display the promastigote-specific antigen, GP46. In contrast, 97% of the organisms maintained for 24 hr at 31 C, pH 7.3, were positive for GP46. Thus, short-term cultivation of this L. amazonensis strain under appropriate conditions can provide a high yield of amastigotes for various in vivo and in vitro studies. However, the possible interference of host immunoglobin on the surface of these amastigotes needs to be considered because fluorescent-labeled anti-mouse immunoglobulin was detected on 16% of lesion-derived amastigotes even after 114 hr of cultivation. 相似文献