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61.
Tadahiko Kawai Nobutoshi Yoshimura 《International journal for numerical methods in engineering》1969,1(1):123-133
The large deflection problem of a rectangular plate is analysed by using the finite element method and employing the iteration technique. In the present study, the stiffness matrix of a rectangular plate element for bending proposed by Greene is employed, and results of numerical examples duly justifies applicability of the present method. 相似文献
62.
Hydrothermal crystal growth of perovskite-type fluorides 总被引:1,自引:0,他引:1
Shigeyuki S¯omiya Shin -Ichi Hirano Masahiro Yoshimura Kazumichi Yanagisawa 《Journal of Materials Science》1981,16(3):813-816
Single crystals of perovskite-type fluorides were grown from potassium fluoride and di-valent metal chloride solutions by
a hydrothermal method under a temperature gradient, at maximum temperature 600° C and pressure 98 MPa. Single-crystal cubes
of KMnF3, KFeF3, KCoF3 and KZnF3, of cube edge sizes ranging from 0.2 to 2.0 mm, were grown. Crystals of KNiF3 grew in rectangular prisms and those of KCdF3 in anhedral form. Single crystals of KCuF3 were grown in pure water from co-precipitated KCuF3 powder. KMgF3 crystals were not grown by this method. 相似文献
63.
Behaviormetrika - Suppose that the correlations ρ12=ρ23=0.9 are given. Then how can ρ13 deviate from 0.9? The answer is 0.62≦ p13≦1, as Tables 1 and 2 in this note show.... 相似文献
64.
Loi Tonthat Hajime Saito Ryuhei Miyamoto Masafumi Suzuki Noboru Yoshimura Kazutaka Mitobe 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(Z1):S1-S6
Recently, the use of a ferromagnetic material in a soft‐heating method has garnered much attention as a novel method for cancer treatment. By concurrently using this material as a thermal probe, we are currently developing a minimally invasive heating and wireless temperature measurement system. To make the approach feasible in a clinical setting, it is vital to overcome the key challenge of heating the local tumor at a constant temperature. In previous conventional approaches, it was necessary to switch the induction‐heating power supply on/off after the target tumor temperature was reached. However, it cannot determine the temperature of the material during the power‐off period. Therefore, we changed this approach and found that by adjusting the distance between the heating coil and the material while maintaining a constant current flow in heating coil, the drift problem, which happened just after power is supplied during the on/off operation, did not occur any longer. Accordingly, it was not required to use multiple sensors to reduce the drift, thereby minimizing the cost. This study verifies the validity of our wireless thermometry approach while performing rotary scanning and proposes a technique for determining achievement of the target temperature. This knowledge complements other approaches for cancer treatment utilizing hyperthermia. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
65.
Serum rheumatoid factor (RF) level and peritoneal and splenic CD5+B (B-1) cells in mice were examined after intraperitoneal administration of purified lipopoly-saccharides (LPS) from oral periodontopathic bacteria; Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum and Capnocytophaga ochracea. F. nucleatum and C. ochracea LPS induced higher levels of serum IgM- and IgG-RF, while P. gingivalis LPS showed the least induction. In addition, wet weights of spleen and serum IgM and IgG concentration were markedly increased in F. nucleatum LPS injected group. On the other hand, the proportion of CD5+ B cells to lymphocytes in the peritoneal cavity and spleen did not increase. The reason for this was not clear but conventional B cells (CD5- B cells) might increase more rapidly with splenic enlargement than CD5+ B cells. These results suggested that RF induced by bacterial LPS may modulate immune responses against bacteria and plays an important role for defence and destruction of periodontal tissue. 相似文献
66.
SMnZn1-xFe2O4 (x=1,0.9,0.8,0.7,0.6,0.5,0.25,0) nanoparticles were prepared by ball-milling hydrothermal and investigated by X-ray diffraction, DTG and TEM, Nanocrystallite grain size was determined by X-ray linewidth to be from 63 (A) to 274 (A). The thermal properties indicate absorbed water still remain at low temperature, crystalline ware will be decomposed from 230 ℃ to 260 ℃, partial Mn2 will be oxidized near 730 ℃. TEM shows the ferrite particles pocess a spherical morphology and uniform nanosize. 相似文献
67.
Aoi Sugiyama Shunji Araki Naonori Sakamoto Tomoaki Watanabe Masahiro Yoshimura 《Journal of Electroceramics》2006,17(1):71-74
Ceramics have generally been fabricated from powders by shape forming & sintering methods except for glasses and glass ceramics.
Glasses and glass ceramics can be fabricated by melting methods. The melting method has not only higher productivity but also
higher shape forming ability than powder processes via forming & sintering methods. Thus we have reinvestigated melting methods
in binary and ternary oxides systems to fabricate amorphous bulk ceramics and bulk nano composites. We have successfully fabricated
amorphous phases by simple melt solidification methods in ternary eutectic melts in the HfO2-Al2O3-Gd2O3system. The present study demonstrates the formation of the amorphous phases in quaternary systems HfO2-Al2O3-Gd2O3-Eu2O3. Furthermore, we have also succeeded to fabricate nano-structured bulk ceramics, which consisted of constituent oxide grains
with 20–100 nm in size, by post annealing of the amorphous phase. 相似文献
68.
69.
The growth and electrical properties of Pb(Yb 1/2 Nb 1/2 )O 3 -PbTiO 3 (PYbN-PT) epitaxial films were investigated. PYbN-PT epitaxial films with SrRuO 3 bottom electrodes were grown by pulsed laser deposition. Optimization of the growth conditions for the PYbN-PT epitaxial films was carried out on (100) SrRuO 3 /(100) LaAlO 3 substrates using the (50/50) composition target. It was found that formation of pyrochlore phase could be caused not only by low growth temperatures or lead deficiency, but also by poor surface condition of the SrRuO 3 bottom electrodes. (001) PYbN-PT epitaxial films with good crystalline quality were obtained for a range of deposition rates (60-100 nm/min) and temperatures (620-680 °C) after vacuum annealing the SrRuO 3 bottom electrodes. The ferroelectric and piezoelectric properties of 1 w m-thick PYbN-PT epitaxial films with (50/50) and (60/40) compositions and with (001) and (111) orientations were investigated using (100) LaAlO 3 , (100) SrTiO 3 , and (111) SrTiO 3 substrates with SrRuO 3 bottom electrodes. The highest remanent polarization (29 w C/cm 2 ) and effective piezoelectric coefficient e 31.f ( m 14 C/m 2 ) were observed in the (001) PYbN-PT (50/50) film. The transition temperature of the (001) PYbN-PT (50/50) film was about 380 °C. Because of the degradation of the target during the deposition, a 3 w m-thick film was prepared by three depositions (1 w m each layer). The 3 w m-thick film exhibited a higher e 31.f coefficient of m 19 C/m 2. 相似文献
70.
This paper reports the study of the dependence of hydrophobicity on the surface appearances and inherent chemical structure of the high-temperature vulcanized silicone rubber (HTVSR) insulator based on the fractal geometric principle. The fractal phenomena link the surface roughness with the hydrophobicity characteristics of silicone rubber (SIR) insulators. The rough surfaces of the insulators, no matter whether due to salt-fog aging or roughening by sandpaper, show the property of a fractal surface. According to the amount of hydrophobic material on the surface, surface roughness exerts different effects on the hydrophobicity of SIR insulators. Due to the behavior of fractal surfaces, the hydrophobicity of the appropriately roughened insulator can be enhanced, but depressed if dipped in hexane. Outdoor polymer insulating materials could be aged by environmental stresses and contaminants so that their surfaces become rough. The permanent change of surface roughness could be an indicator of aging state of the insulation material. The hydrophobicity of SIR insulators aged in salt fog in a fog chamber are investigated. During this aging, the inorganic filler and the hydrophobic groups in SIR are worn away so that the insulator surface becomes rough. The surface of the aged insulator becomes hydrophilic. After a subsequent rest, the hydrophobic polymer liquid in bulk diffuses and migrates to the insulator surface, which becomes more hydrophobic. Such a unique dependency of hydrophobicity on the surface appearance and chemical structure of SIR material is available for SIR insulator to maintain good contamination performances in outdoor applications 相似文献