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51.
We figure optical surfaces by plasma chemical vaporization machining (CVM) with a pipe electrode, in which an rf plasma generated at the electrode tip under approximately atmospheric pressure moves over the surfaces. We propose a shaping method in which the movement of plasma on the surfaces can be determined. Flat and aspheric surfaces are successfully figured with the desired peak-to-valley shape accuracy of 0.1 microm. The root-mean-square roughness of the resultant surfaces is at the subnanometer level. These results confirm that the plasma CVM and the shaping method have the capability to fabricate optics with high accuracy.  相似文献   
52.
Intra-molecular mobility of positive charge carriers in poly(n-hexyl-[S]-2-methylbutylsilane) (PHMBS) films doped with N,N′-bis(2,5-di-tert-buthylphenyl)-3,4,9,10-perylenedicarboximide (PDI) is studied by time-resolved microwave conductivity (TRMC) measurements. PHMBS with optically active side chains has a rod-like tightly locked Si catenation with unlikely long persistence length compared with conventional dialkyl-substituted polysilanes. It was found that PDI is a suitable electron acceptor for PHMBS as it provides the high product of photo carrier generation yield ? as ~0.08% under an excitation at 355 nm. The efficient electron transfer reaction from PHMBS to PDI gives clear conductivity transients ascribed to the positive charges on the Si catenation of PHMBS by TRMC measurements. The estimated value of isotropic mobility along the tightly locked Si catenation is 0.36 cm2 V?1 s?1, suggesting the presence of mobile holes on the backbones of PHMBS.  相似文献   
53.
Abstract— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro‐reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper.  相似文献   
54.
Recently, there has been much interest in the study of the formation of groups of agents that cause interactions between agents and invent new functions. We gave some agents an action rule based on the interactions of human feelings by using a circumplex model. It had been decided that the parameters of feelings in this model should have only two axes. In this report, eight basic action dimensions and pure feelings on four corresponding axes were given to agents as a model of feelings and actions based on the multiple factor analysis theory of R. Plutchik, and the behavioral characteristics of the group of agents were examined.  相似文献   
55.
A stationary packed bed of cohesionless particles is set up in a vertical pipe for the fundamental study of plug conveying. The effect of flow acceleration or deceleration on the pressure drop of the plug is investigated first. It is found that the pressure drop increases due to the flow acceleration and vice versa. Next, the following three kinds of experiments were made for the study of friction characteristics: 1. Friction between the plug and moving wall without air flow, 2. Friction between the plug and wall with downward air flow, 3. Friction between the plug and wall with upward air flow. The results are compared with the theory established in powder mechanics. The state of stress being of the active or passive case is discussed. Finally the problem of particles raining down from the back of the plug is studied. It is shown that the air velocity necessary to support the particles can be calculated based on a simple analysis of pressure distribution around the particles.  相似文献   
56.
To investigate the prevalence and clinical characteristics of diabetes mellitus caused by mitochondrial gene mutations in the tRNA[Leu(UUR)] region, a known 'hot spot' for pathogenic mutations, we screened 440 diabetic patients with diabetic mothers for 11 mitochondrial gene mutations reported in mitochondrial neuromuscular disorders; nucleotide pairs (np) 3250, 3251, 3252, 3254, 3256, 3260, 3271, 3291, 3302 and 3303 in addition to an A to G transition at np 3243. The dot-blot hybridization method using 32P-labelled sequence-specific oligonucleotides as probes was used. One subject carrying a T to C transition at np 3271 and seven carrying the A to G transition at np 3243 were identified, while none of the other diabetic patients screened had these mutations in the tRNA[Leu(UUR)] region. The patient with the 3271 mutation, a 39-year-old male, had excellent glycaemic control with diet alone and had neither hearing impairment nor symptoms suggesting mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). Thus, among patients with maternally transmitted diabetes, the prevalence of the 3271 mutation was approximately one-seventh that of the 3243 mutation, and other mutations are even more rare in the mitochondrial tRNA[Leu(UUR)] region.  相似文献   
57.
Void formation is aluminum lines caused by high-temperature heat treatment has been investigated, particularly from the aspect of mechanical interaction between the passivation layer and aluminum lines. It is found that there are two effects causing voids in aluminum lines: the deformation of the passivation layer and the so-called thermal expansion mismatch between aluminum lines and their surrounding layers. While the thermal expansion effect is independent of aluminum line dimensions, the passivation deformation effect dominates preferentially in wide aluminum lines. Bulge deformation of the passivation layer is caused by its own compressive stress, forcing the encapsulated aluminum to expand. In fine lines, void formation is controlled by the volume difference caused by the thermal expansion mismatch and aluminum diffusion  相似文献   
58.
Pure aluminium and high-silicon aluminium alloy were reinforced with the discontinuous pitch-based carbon fibres by squeeze casting, then the thermal conductivity and the mechanical properties of the composites were investigated. Optical microscopy revealed that the fibres were in a random planar arrangement, and the transmission electron microscopy revealed that there is no interfacial reaction between the matrices and the fibres. The random planar arrangement of the fibres leads to the anisotropy of the composite. The fibre-reinforcement increased the thermal conductivity in the parallel direction for both pure aluminium and its alloy matrices, while the thermal conductivity decreased in the vertical direction. The increase in the elastic modulus by the reinforcement was not observed for both matrices. The proof stress of the pure aluminium increased by the reinforcement especially in the parallel direction, while that of the high-silicon alloy decreased by the reinforcement.  相似文献   
59.
Nanocomposites of isotactic polypropylene (iPP) and multiwalled carbon nanotubes (MWCNTs) with various contents of MWCNTs were fabricated by double molding techniques. X‐ray diffraction measurements reveal a development of α‐crystal with lamellar stacks having a long period of 150 Å in the neat iPP that increases to 165 Å in 2 wt % MWCNTs‐loaded composites, indicating that MWCNTs enhance crystallization of iPP as a nucleating factor. Mechanical properties, such as tensile strength, flexural strength, Young's modulus, tangent modulus, and microhardness are found to increase with increasing MWCNTs content. Thermal analyses represent an increase of crystallization and melting temperatures and a decrease of thermal stability of the composites with increasing MWCNTs. Changes in structural, mechanical, and thermal properties of the composites due to the addition of MWCNTs are elaborately discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
60.
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。  相似文献   
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