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31.
A sparse mask that persists beyond the duration of a target can reduce its visibility, a phenomenon called object substitution masking. Y. Jiang and M. M. Chun (2001a) found an asymmetric pattern of substitution masking such that a mask on the peripheral side of the target caused stronger substitution masking than on the central side. Assuming spatial attention was focused toward the target, the peripheral and central masks were located in the same and opposite direction of an attentional path with reference to the target in their study. We hypothesized that this asymmetric mask configuration relative to the attentional shift contributes to asymmetric substitution masking. To test this hypothesis, we conducted four experiments among which the presence or absence of the center–periphery relationship and the presence or absence of the asymmetric mask configuration were manipulated independently and orthogonally. The results suggest that asymmetric substitution masking occurs relative to the direction of spatial attention irrespective of the central–peripheral relation. We propose that the asymmetry in substitution masking might be explained by attentional momentum associated with orienting toward the target. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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33.
The effect of water concentration on the foaming tendency of lubricating oil containing the detergent additives Ca-phenate and amide was investigated from a surface chemical standpoint. Foam volume, dynamic surface tension and surface viscosity were measured at various water concentrations. It was proved that the increase of surface viscosity with water content was the main factor affecting foaming in the case of Ca-phenate but, in contrast, the Marangoni effect played an essential role in the case of amide. 相似文献
34.
A compact sodium-cooled reactor is an important candidate as a fast breeder reactor (FBR) and has been investigated in the feasibility study of FBR cycle. Due to the compact sizing of the reactor vessel, gas entrainment at the free surface of sodium coolant becomes one of the significant issues for reactor design, and it is required to clarify the criterion of gas entrainment at free surface and the tolerance. In the present study, some visualization experiments were performed in a water-air system focusing on the gas entrainment due to surface vortex and its transient phenomena. Influences of horizontal velocity were clarified by the visualization. The gas entrainment due to the surface vortex occurs intermittently. Time trends of circulation and length of gas core for the intermittent surface vortices were measured by the particle image velocimetry and visualization. It was found that the gas core length extends with time delay to the increase of circulation around the vortex. 相似文献
35.
We report a unique nano-ridge structure of zinc oxide (ZnO) and its application in high performance inverted polymer solar cells. The ZnO nano-ridge structure was formed by a sol–gel process using a ramp annealing method. As the solvent slowly evaporated due to the low heating rate, there was sufficient time for the gel particles to structurally relax and pile up, resulting in a dense and undulated film. Nano-ridges with peak as high as 120 nm and valley to valley distance of about 500 nm were formed. This film provided an effective hole blocking layer and also an increased interfacial area for electron collection. An inverted bulk heterojunction polymer solar cell was fabricated using the ZnO nano-ridge film as the electron collecting layer. The device showed a high power conversion efficiency of 4.00%, an improvement of about 25% over similar solar cells made with a planar film of ZnO nanoparticles. 相似文献
36.
The authors fabricated thin films by solution processes using liquid-crystalline (LC) semiconductors, 5-alkyl-5’’-(4-hexyltetrafluorophenyl)-2,2’:5’,2’’-terthiophene (2–5). Films of 5-propyl-5’’-(4-hexyltetrafluorophenyl)-2,2’:5’,2’’-terthiophene (2) show similar molecular packing as their non-fluorinated counterparts. However, the degree of molecular packing ordering from X-ray diffraction measurement is higher, and the films exhibit a more crystal-like structure. Moreover, fluorination has a remarkable effect on their mesomorphic behaviors. Films of 2 consist of large size LC domains (in the range of 100 μm) at room temperature. Thin-film transistors (TFTs) of 2 show p-type operation with good hole mobility up to 0.027 cm2/Vs as well as improved operation stability under ambient conditions and high on/off ratio. Tetrafluorophenyl substitution leads to lowering of HOMO energy by 0.15 eV for 2 and 0.35 eV for 5, resulting in operation stability. Variable-temperature current-voltage measurements indicate intrinsic carrier transport in films of 2. 相似文献
37.
Koichiro Koyama Masao Morishita Tomohiro Harada Nobuyuki Maekawa 《Metallurgical and Materials Transactions B》2003,34(5):653-659
The standard Gibbs energies of formation of Fe2Mo3O12, Fe2Mo3O8, FeMoO4, and Fe2MoO4 of the Fe-Mo-O ternary system and the μ phase of the Fe-Mo binary system have been determined by measuring electromotive forces of galvanic cells having an Y2O3-stabilized ZrO2 solid electrolyte. The results are as follows: $$\begin{gathered} \Delta _f G^\circ (FeMoO_4 )/kJ \cdot mol^{ - 1} = - 1053.5 + 0.2983(T/K) \pm 0.4 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_8 )/kJ \cdot mol^{ - 1} = - 2347 + 0.6814(T/K) \pm 1 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_{12} )/kJ \cdot mol^{ - 1} = - 2993 + 0.9105(T/K) \pm 2 \hfill \\ Temperature range: 1040 to 1145 K \hfill \\ \Delta _f G^\circ (Fe_{0.58} Mo_{0.42} )/kJ \cdot mol^{ - 1} = - 18.7 + 0.0117(T/K) \pm 0.1 \hfill \\ Temperature range: 1162 to 1223 K \hfill \\ \Delta _f G^\circ (Fe_2 MoO_4 )/kJ \cdot mol^{ - 1} = - 1174 + 0.342(T/K) \pm 1 \hfill \\ Temperature range: 1243 to 1466 K \hfill \\ \end{gathered} $$ where the standard pressure is 1 bar (100 kPa). 相似文献
38.
Emissions and environmental implications of mercury from artisanal gold mining in North Sulawesi,Indonesia 总被引:1,自引:0,他引:1
Limbong D Kumampung J Rimper J Arai T Miyazaki N 《The Science of the total environment》2003,302(1-3):227-236
In artisanal gold mining practiced in North Sulawesi Island, Indonesia, gold is separated from ore by the use of mercury, which forms an amalgam with gold. All related processes are undertaken with a low level of technical knowledge and skills, no regulation, and with disregard for the safety of human and environment health. The situation is generating serious potential health and environmental risks in the area. As part of an ongoing monitoring program, total mercury concentrations were examined in water, bottom sediment and fish samples from three main rivers in Talawaan Watershed, which receives drainage from gold mining practices. Monitoring began in May-June 2000, almost 2 years after artisanal gold mining had begun. At that time, the mercury concentration in the sediment was generally low, except in places close to the gold processing plants. In the present study, a more systematic sampling and analysis was conducted in May-June 2001. Bottom surface sediments, water, and fish samples were collected at 12 sites along the three main rivers in the watershed. In addition, one site outside the watershed was sampled to serve as a control. Sample collections were conducted in three phases in duplicate, with two-week intervals between each phase. The mercury concentration observed in this study indicated that an increase took place along the three main rivers in the watershed. Solutions to this problem must be formulated as soon as possible in order to avoid a major health, economic, and ecological disaster arising from the continuing discharge of Hg. The present study proposes that mercury dispersion occur downstream of the mining. 相似文献
39.
In order to discover the effect of heating direction on the thermocapillary convection, three-dimensional numerical simulations have been conducted in a shallow annular pool (depth d=1 mm) of silicone oil (0.65 cSt, Pr=6.7) differentially heated from the inner wall. The linear stability analysis predicts a critical temperature difference (ΔTc) for the incipience of hydrothermal wave (HTW) is 4.58K, which is less than ΔTc=5.0K for a pool heated at the outer wall. Numerical simulations predict that two groups of HTWs, propagating in azimuthal directions opposite to each other, always coexist in the pool. Simulations with pool rotation around the axis elucidate that pool rotation up to 1.05 rad/s gives no distinguishable effect on the behavior of HTW in an inner heated pool, whereas the HTW patterns in an outer heated pool are significantly modified by rotation. 相似文献
40.
Toshifumi Ohkubo Nobuyuki Terada Yoshikazu Yoshida 《Microsystem Technologies》2013,19(9-10):1319-1328
An optical sensor combined total analysis system (TAS) is thought to be one of the most powerful functional elements needed to realize a “ubiquitous human healthcare” system. In accordance with this concept, we have proposed a fundamental structure of detecting side scattered light from a minute cell or particle running along a microfluidic channel, partially utilizing the channel filled with water or saline solution as a light waveguide. Based on this concept, we have fabricated a trial-manufactured optical TAS chip and carefully evaluated its side scattered light measuring performance in in-plane direction, supplying and detecting visible laser power by using multiple optical fibers and their precise positioning mechanisms. We have successfully obtained experimental results of both transmitted light power change and that of side scattered light, and we confirmed that there was a strong relationship between their signal waveforms. Furthermore, we have developed a hybrid numerical calculation method on the basis of the finite-difference time-domain method, in addition to the beam propagation method. Based on this hybrid method, we tried to compare results between the experimental inverse pulse of transmitted light and a pulse of side scattered light, and those based on numerical calculations. Excellent qualitative accordance was obtained between the inverse pulse of numerical and experimental results. In contrast, the experimental pulse of side scattered light indicated a considerably spread base in comparison to the numerical results. 相似文献