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排序方式: 共有521条查询结果,搜索用时 15 毫秒
1.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
2.
ShinsukeSonoda 《世界电子元器件》2004,(6):30-30,38
随着MP3音频压缩和CD技术的普及,消费者开始希望这些功能和便利性也能在其他常用设备包括汽车中实现。因此,制造商开始在汽车内引入数字媒体处理技术,使司机和乘客能数字化地获得娱乐和信息。 相似文献
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Hiroshi Ito Takehiko Ishiguro Tokutaro Komatsu Nozomu Matsukawa Gunzi Saito Hiroyuki Anzai 《Journal of Superconductivity and Novel Magnetism》1994,7(3):667-669
The superconducting transition of the organic compoundsκ-(BEDT-TTF)2 X is studied by resistive measurement in a magnetic field up to 10 T applied normal to the conducting plane. For the salts withX=Cu[N(CN)2]Br andX=CuCN[N(CN)2] the transition shows fanshaped broadening caused by superconductivity fluctuation. For theX=Cu(NCS)2 salt the resistivity shows a peak in the transition region in a magnetic field below 4 T.This phenomenon is suppressed in defect-reduced samples for intralayer conduction. We discuss this peak in relation to the thermal fluctuation on the Josephson junction structures in this salt. 相似文献
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A new radially local neoclassical transport code is developed based on the radially global two-weight δf Monte Carlo code, FORTEC-3D (Satake et al., 2008). In the collisional two-weight δf method, the variance of weight increases in time due to the so-called weight spreading, which leads to an increasing numerical noise in long time simulations. A new improved control-variate scheme was proposed by Kleiber et al. (2011) to reduce the variance. We investigate the effectiveness and validity of the new control-variate scheme for a practical collisional transport problem in a plasma described by the drift kinetic equation. It is demonstrated that the new scheme reduces the variance of weight by approximately 75% in an axisymmetric magnetic field configuration. The burst-like behavior of a transport observable caused by a large numerical noise can be avoided. As a result, the time evolution of a transport observable can be successfully smoothed. 相似文献
7.
Shinsuke Nagamine Yosuke Mizuno Yuta Hikima Kiyomi Okada Long Wang Masahiro Ohshima 《应用聚合物科学杂志》2021,138(7):49851
Cellulose microfibers (CMFs) having surfaces modified with polydopamine (PDPA) and octadecylamine (ODA) were prepared, and their reinforcing abilities for polypropylene (PP) were investigated. The PDPA coating was made via self-polymerization of dopamine (P-CMF), and subsequent alkylation was conducted by the reaction with ODA (OP-CMF). The modified CMFs exhibited improved dispersibility in the PP matrix due to the reduced hydrophilicity. The OP-CMF/PP composite prepared by batch mixing had a higher tensile modulus compared to that for the pure PP and composites with unmodified CMFs. However, excess alkylation lowered the tensile modulus, and the presence of an optimal degree of alkylation was demonstrated. The CMF/PP-IM composites fabricated by injection molding exhibited improved tensile properties compared to those prepared by batch mixing. Both the tensile modulus and yield stress were increased by increasing the CMF content and improved by the surface modification of the CMFs. 相似文献
8.
Pressure effects on the low temperature state of the α-(BEDT-TTF)2MHg(SCN)4 organic conductor family
X. Chen J. S. Brooks S. Valfells G. J. Athas S. J. Klepper M. Tokumoto N. Kinoshita H. Anzai Y. Tanaka 《Synthetic Metals》1995,70(1-3)
Systematic magnetotransport measurements as a function of hydrostatic pressure have been made on four members of the α-(BEDT-TTF)2MHg(SCN)4 organic conductor family (M = K, Tl, Rb, NH4). Applied pressure above about 6 Kbar removes the density wave state for M = K, Tl, and Rb. For M = NH4 the superconducting state is removed with pressure as dTc/dP = − 0.25 K/Kbar. In all cases the Shubnikov de Haas oscillation frequency increases with pressure, including the β orbit (which involves the entire Brillouin zone), and new orbits involving very small fractions of the Fermi surface are formed. 相似文献
9.
Mathematical models of neurons are widely used to improve understanding of neuronal spiking behavior. These models can produce artificial spike trains that resemble actual spike train data in important ways, but they are not very easy to apply to the analysis of spike train data. Instead, statistical methods based on point process models of spike trains provide a wide range of data-analytical techniques. Two simplified point process models have been introduced in the literature: the time-rescaled renewal process (TRRP) and the multiplicative inhomogeneous Markov interval (m-IMI) model. In this letter we investigate the extent to which the TRRP and m-IMI models are able to fit spike trains produced by stimulus-driven leaky integrate-and-fire (LIF) neurons. With a constant stimulus, the LIF spike train is a renewal process, and the m-IMI and TRRP models will describe accurately the LIF spike train variability. With a time-varying stimulus, the probability of spiking under all three of these models depends on both the experimental clock time relative to the stimulus and the time since the previous spike, but it does so differently for the LIF, m-IMI, and TRRP models. We assessed the distance between the LIF model and each of the two empirical models in the presence of a time-varying stimulus. We found that while lack of fit of a Poisson model to LIF spike train data can be evident even in small samples, the m-IMI and TRRP models tend to fit well, and much larger samples are required before there is statistical evidence of lack of fit of the m-IMI or TRRP models. We also found that when the mean of the stimulus varies across time, the m-IMI model provides a better fit to the LIF data than the TRRP, and when the variance of the stimulus varies across time, the TRRP provides the better fit. 相似文献
10.
Recently, various robots with many degrees of freedom, such as rescue robots and domestic robots, have been developed and
used in practical applications. It is difficult to control such robots autonomously in real environments, because in order
to control the many degrees of freedom, we have to observe many states, calculate huge amounts of information, and operate
many actuators. In this study, we consider a flexible robot without sensors or controllers that can determine the inclination
of a slope and climb up the slope. In order to demonstrate the effectiveness of the proposed framework, we have developed
a prototype robot and conducted experiments. The result indicates that the robot could determine the inclination and climb
up a gentle slope autonomously. Thus, we have realized an autonomous robot that has no explicit sensors or controllers. 相似文献