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91.
The oxidation of propane has been investigated in the presence and absence of tetrachloromethane (TCM) on calcium hydroxyapatite
(CaHAp), Ca3(PO4)2, CaSO4 and CaO at 723 K. In the absence of TCM, the conversion of C3H8 on CaHAp was 7.7–9.2% during 6 h on-stream while that on Ca3(PO4)2, CaSO4 and CaO was 0.6, 0 and 0.2–0.4%, respectively. The principal products on all catalysts in the absence of TCM were CO and
CO2 with small selectivities to C3H6 and C2H4 (both 5–6%) observed on CaHAp. Upon addition of TCM, the selectivity to C3H6 on all catalysts and the conversion of C3H8 on CaSO4 increased while, with increasing time-on-stream, the changes in the conversion and selectivity were dependent upon the nature
of the catalysts. XPS and XRD analyses provide evidence for the presence of chlorine in the surface and/or bulk of three of
the catalysts, suggesting that chlorinated species on the solids play a role in the selectivity enhancement, but the absence
of chlorine from the sulphate demonstrates the dissimilarities of the catalysts in their abilities to sorb and decompose TCM.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
92.
Effects of poly(propylene carbonate) additive prepared from carbon dioxide on the tensile properties of polypropylene 下载免费PDF全文
We investigated the effect of a rubbery poly(propylene carbonate) (PPC) additive on the tensile properties of isotactic polypropylene (iPP). PPC materials were produced from carbon dioxide gas. Although the elongation of iPP was reduced at higher elongation speeds, PPC addition improved the elongation at break at higher elongation speeds. iPP/PPC blends showed a high drawability while maintaining a high stress level. The failure mechanisms at high elongation speeds were different between the iPP and iPP/PPC samples. Craze‐like voids appeared along the stretching direction for pure iPP, whereas the PPC additive yielded craze‐like voids that were perpendicular to the stretching direction. The addition of PPC doped with carbon nanodots enhanced the yield toughness of iPP at high elongation speeds. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45266. 相似文献
93.
The compatibility for binary blends of isotactic polypropylene with rubbery ethylene-α-olefin copolymers having various α-olefin contents was investigated by means of differential scanning calorimetry, X-ray analysis, transmission electron microscopy, and dynamic mechanical analysis. It was found that “α-olefin rich” in ethylene-1-butene copolymers and in ethylene-1-hexene copolymers were miscible with amorphous polypropylene chains, when the α-olefin content is above 50 mol %. On the other hand, the blends with “ethylene rich” (above 50 mol % of the ethylene content) in ethylene-1-butene copolymers and ethylene-1-hexene copolymers showed a microheterogeneous morphology. © 1996 John Wiley & Sons, Inc. 相似文献
94.
Magnetization reversal processes in microstructured NiFe rings are studied by fringe-field-induced local Hall magnetometry.
This semiconductor-based technique yields a high sensitivity of magnetic stray fields and allows us to detect magnetization
hysteresis loops of single NiFe rings. The transition fields can be controlled by the ratio between inner- and outer-ring
diameter. Comparison between Hall measurements and numerical simulation suggests that there are four different magnetization
states in two integrated rings.
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95.
T Yambe S Nanka S Kobayashi A Tanaka M Yoshizawa K Abe K Tabayashi H Takeda S Nitta 《Canadian Metallurgical Quarterly》1998,44(5):M700-M703
To develop the optimal automatic control algorithm for an in vivo artificial heart system, investigation of the basic characteristics of the cardiovascular system may be important. The clinical significance of chaotic dynamics in the cardiovascular system has attracted attention. The circulation is a so-called complex system with many feedback circuits, making it very difficult to investigate the origin of chaos within the system. In this study, we investigated the origin of chaos by open loop analysis with an artificial heart (which has no fluctuation in pumping rate or contraction power) in chronic animal experiments with healthy adult goats. As a result, in the artificial heart circulatory time series data, low dimensional deterministic chaos was discovered by nonlinear mathematical analysis, suggesting the importance of blood vessels in the chaotic dynamics of the cardiovascular system. To investigate the origin of chaos further, sympathetic activity was directly measured in animals with artificial hearts. Chaotic dynamics was also recognized in sympathetic action potentials, even during artificial heart circulation. Coupling of the nonlinear information between blood vessels and sympathetic activity was suggested by analysis of mutual information. In chaotic dynamics, the central nervous system (CNS) played an important role through sympathetic activity. These findings may be useful for the development of an automatic control algorithm for an artificial heart. 相似文献
96.
Katsumi Nitta Yoshihisa Ohtake Shigeru Maeda Masayuki Ono Hiroshi Ohsaki Kiyokazu Sakane 《New Generation Computing》1993,11(3-4):423-448
This paper presents HELIC-II, a legal reasoning system on the parallel inference machine. HELIC-II draws legal conclusions for a given case by referring to a statutory law (legal rules) and judicial precedents (old cases). This system consists of two inference engines. The rule-based engine draws legal consequences logically by using legal rules. The case-based engine generates legal concepts by referencing similar old cases. These engines complementally draw all possible conclusions, and output them in the form of inference trees. Users can use these trees as material to construct arguments in a legal suit. HELIC-II is implemented on the parallel inference machine, and it can draw conclusions quickly by parallel inference. As an example, a legal inference system for the Penal Code is introduced, and the effectiveness of the legal reasoning and parallel inference model is shown. 相似文献
97.
Superconducting generators have many advantages, one of which is their ability to improve the stability of power systems because of their low synchronous impedances. The advantage may be increased by adoption of high-response excitation. The first 100 kVA high-response excitation superconducting generator has now been built. One of the problems in the design of such generators involves the characteristics of the field circuit, i.e., the field armature winding, losses in the component materials, and loss in the superconducting field winding. In this paper, a 2-dimensional electromagnetic field analysis of field circuit characteristics is presented. 相似文献
98.
99.
Modeling legal argumentation is one of the most important research in AI and Law, and a lot of models have been proposed. However, most research has not treated value judgement and debate. In this paper, we introduce a legal reasoning model which covers various aspects of legalreasoning such as making argument, selecting argument and debate.Furthermore, we present how criminal law is described and reasoned inthis model. 相似文献
100.
The inhomogeneous structure of agar gels was examined by means of mechanical-scanning probe microscopy. Several domains were observed in the elasticity images, while such domains could not be seen in the height images. The domain size decreased with increases in agar concentration. We found that the histograms of the logarithm of the local elastic modulus were described well by a single normal distribution. As the agar concentration increased, the peak values of the histograms increased, while the half-value width remained constant. These results imply that the gelation process of agar gels has a common mechanism, despite its complexity. 相似文献