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151.
Takuji Kobayashi Katsuhiko Sasaki 《Journal of Materials Science: Materials in Electronics》2009,20(4):343-353
This paper discusses uniaxial ratchetting deformation of lead-free solder alloy Sn–3Ag–0.5Cu and lead-containing solder alloy
Sn–37Pb, which were subjected to tension–compression loading with several stress amplitudes and stress ratios, minimum stress
over maximum stress. First the uniaxial ratchetting tests were conducted with three maximum stresses and four stress ratios.
All tests were conducted using cylindrical bulk specimens of the solder alloys at 313 K. The test results show that there
are differences in the ratchetting deformation behavior of the two solder alloys; the larger ratchetting strain occurs in
the lead-containing solder alloy than in the lead-free solder alloy. The ratchetting deformation was simulated by the dislocation
based constitutive model proposed by Estrin et al. (J Eng Mater Technol 118:441, 1996). The evolution equation of the back
stress employed in the constitutive model was modified considering a dynamic recovery term. The effect of the modification
of the back stress evolution is discussed by comparing the simulations with the corresponding experimental results. The simulations
suggest that the recovery term in the kinematic hardening rule plays an important role in fitting the simulation to the experimental
results of the ratchetting deformation of the solder alloys. 相似文献
152.
Kaoru Abe Yasuhiro Sakurai Akira Okuyama Kazuhiro Sasaki Kei Tawarada 《Journal of the science of food and agriculture》2009,89(6):1097-1100
BACKGROUND: The behavior of cadmium in ecosystems needs to be monitored because of the human toxicity of this heavy metal. The need recently arose for a simple and quick on‐site test for trace levels of Cd in food and environmental samples. In response, an immunochromatographic assay kit for detecting Cd was manufactured by Kansai Electric Power Co. of Japan. This kit uses the antigen–antibody complex reaction between the Cd–EDTA complex and an anti‐Cd–EDTA antibody and shows the results in terms of the degree of color developed on a test paper. We previously reported the successful use of this kit to determine Cd concentrations in brown rice. Here, we applied the kit to the determination of Cd concentrations in rice foliage and soil. RESULTS: Cadmium in rice foliage was not extracted successfully by the method used for brown rice. However, it was successfully extracted by 0.1 mol L?1 HCl solution at a rice foliage:HCl ratio of 1:20, and coexisting metals were removed sufficiently by the column treatment. The Cd concentrations determined by immunochromatographic assay were well correlated with the values obtained by acid decomposition and inductively coupled plasma mass spectrometry. The 0.1 mol L?1 HCl‐extractable Cd concentration in soil was also determined successfully with the kit. CONCLUSION: Approximate Cd concentrations in rice plants and 0.1 mol L?1 HCl‐extractable Cd concentrations in soil can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2009 Society of Chemical Industry 相似文献
153.
154.
Mizutani A Kikuta H Iwata K Toyota H 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(7):1346-1351
We describe a new structure of guided-mode resonant grating (GMRG) filters with low sideband reflectance. This GMRG filter consists of a high-index thin film on an antireflective structured surface called "moth-eye structure." Since the high-index film undulates along the surface structure, the film acts as a modulated optical waveguide. An incident light wave satisfying a resonant condition is reflected by the GMRG filter, and nonresonant light waves pass through the filter. This GMRG filter is valid for reducing reflection of nonresonant light waves in a wide spectral range. The resonant reflection of this new filter was investigated by numerical calculation based on an electromagnetic grating analysis. In the case of a triangular antireflective surface structure whose thickness is 2x greater than its period, the sideband reflectance for nonresonant light waves was lower than 0.5% for TM-polarized light in a wide range of wavelengths. 相似文献
155.
A surface profiler that incorporates a feedback controller to eliminate external disturbances is proposed and demonstrated. Its overall performance is dependent on the frequency response of the feedback loop. The frequency of the modulating signal strongly influences the response of the feedback controller. When we used the integrating-bucket method, the CCD camera had to be operated at a low-frequency video rate. Our technique uses a CCD camera equipped with an electronic shutter. The shutter function enables us to apply high-speed sinusoidal phase modulation to the conventional integrating-bucket method under the standard video rate. 相似文献
156.
T. Isa T. Fukase M. Sasaki M. Koyano N. Taniguchi T. Kimura Y. Isobe H. Negishi 《Journal of Low Temperature Physics》2002,127(1-2):63-79
We have measured electrical resistivity, Hall coefficient, thermoelectric power, and magnetization for charge-density wave (CDW) material 1T-TaS2 single crystals grown by varying the excess sulfur content x
es. We have revealed that a small mid-gap state is formed inside the Mott gap and that anomalous low temperature transport is not governed by the Mott gap state itself but by the mid-gap state. The electric properties of the mid-gap state are modified by increasing x
es (or hole doping), and we have found the insulator-metal transition occurs by hole doping below 60K. 相似文献
157.
Y. Ikeda T. Shibutani M. Sasaki S. Shoji N. Yamada 《Journal of Materials Science》2002,37(18):3861-3866
Graft polymerization of methacrylic acid onto ABS resin was carried out using BPO as an initiator in THF solution. Degree of grafting increased with reaction time and reached 35% in 10 hrs. Carboxyl groups were converted to carboxylates (metal salts) by refluxing MAA-g-ABS and the metal acetate in THF. In the solid graft polymers in solid, the infrared absorption of the asymmetrical C= O vibration of the carboxylic acid shifted to lower wavenumbers with increasing metal ion concentration. The absorption peak for the carboxylate anion is shifted to higher wavenumbers with the increase of alkali metal ion concentration, however, for the Mg2+ salt, it is shifted to lower wavenumbers. The surface and volume resistivities of the K+ and Na+ salts of MAA-g-ABS were 9.0 × 109 and 9.5 × 109 at 80% neutralization, respectively, and decreased with alkali metal ion concentration. The electric resistance of Li+, Mg2+ and Zn2+ salts decreased only slightly. The modulus of the K+ salt of MAA-g-ABS decreased with neutralization, whereas in Li+, Mg2+ and Zn2+ salts, the modulus increased with increasing metal ion concentration. 相似文献
158.
Keisuke Hachisuka Teruhito Takeda Yusuke Terauchi Ken Sasaki Hiroshi Hosaka Kiyoshi Itao 《Microsystem Technologies》2005,11(8-10):1020-1027
Intra-body communication is a wireless means of exchanging information within a personal area network (PAN) between wearable electronic sensors and devices. The feasibility of intra-body communication is confirmed through several experiments on signal propagation within the human body, and a human phantom is designed and used to obtain reproducible results over repeated experiments. Based on the results of these experiments, a prototype transmission system is constructed using aluminum electrodes powered by 3 V DC and operating in the 10.7 MHz frequency modulation (FM) band. This prototype is demonstrated to be capable of transmitting analog signals through the human subjects in the presence of external noise. Digital data transmission at 9600 bps is also achieved using newly fabricated 10.7 MHz frequency shift keying (FSK) transmitter and receiver devices. The carrier frequency of 10.7 MHz is the intermediate frequency of FM radio receivers, meaning that the proposed system can make use of a wide selection of inexpensive, commercial radio frequency devices. 相似文献
159.
Hiroyasu Hotokezaka Noboru Aoyagi Yasuhiro Kawahara Noriko U. Yamaguchi Shinya Nagasaki Ken Sasaki Satoru Tanaka 《Microsystem Technologies》2005,11(8-10):974-979
Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Al2O3, CaCO3 and MgO particles suspended in water. In the single elemental system, the plasma emission intensities of Al, Ca and Mg were linearly increased with concentration of elements in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 8.0×10?5 –4.0×10?3 M, respectively. We also investigated the concentration dependence of breakdown spectra for suspended mixtures of Al2O3, CaCO3 and MgO particles. The emission lines, such as Al I, Ca I, Ca II and Mg I, were appeared in the LIBS spectrum simultaneously, and each emission peak could be deconvoluted. The plasma emission intensities of Al, Ca and Mg in the multielemental system were also linearly increased with their concentrations in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 4.0×10?4–2.0×10?3 M, respectively. LIBS was found to be available for quantitative and qualitative measurement of the concentrations of Al2O3, CaCO3 and MgO particles suspended in water. The present results suggest that LIBS is a potentially useful tool for in-situ analysis on particles composition and concentrations for environmental monitoring by the wearable information equipments. 相似文献
160.
Muramatsu D. Kondo M. Sasaki M. Tachibana S. Matsumoto T. 《Information Forensics and Security, IEEE Transactions on》2006,1(1):22-34
Authentication of handwritten signatures is becoming increasingly important. With a rapid increase in the number of people who access Tablet PCs and PDAs, online signature verification is one of the most promising techniques for signature verification. This paper proposes a new algorithm that performs a Monte Carlo based Bayesian scheme for online signature verification. The new algorithm consists of a learning phase and a testing phase. In the learning phase, semi-parametric models are trained using the Markov Chain Monte Carlo (MCMC) technique to draw posterior samples of the parameters involved. In the testing phase, these samples are used to evaluate the probability that a signature is genuine. The proposed algorithm achieved an EER of 1.2% against the MCYT signature corpus where random forgeries are used for learning and skilled forgeries are used for evaluation. An experimental result is also reported with skilled forgery data for learning. 相似文献