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101.
The pharmacokinetics of water-in-oil-in-water-type multiple emulsion of a new tacrolimus formulation
Takeji Uno Takaji Yamaguchi Xiao Kang Li Yoshinari Suzuki Hisakuni Hashimoto Yukio Harada Taizou Kimura Teruhisa Kazui 《Lipids》1997,32(5):543-548
We developed a water-in-oil-in-water (W/O/W)-type multiple emulsion of a new tacrolimus formulation. A potential approach
to avoid the complications of systemic immunosuppression and simultaneously enhance immunosuppressive efficacy is to deliver
immunosuppressive agents locally to the site of the target organs. The W/O/W emulsion is dispersed oil drops containing smaller
water droplets that allow the delivery of drugs preferentially to the reticuloendothelial system (RES). Since the liver and
the spleen are primary components of the RES, and the brain and the kidney have a poor RES, we hypothesized that a W/O/W emulsion
of tacrolimus would prossess the pharmacokinetic benefits of local immunosuppression. We evaluated this hypothesis in a rat
model. The tacrolimus levels of whole blood, the liver, spleen, brain, and kidney in rats given intravenous emulsions of tacrolimus
(W/O/W group) were compared with a group administered tacrolimus alone (T group). There were no significant differences between
the pharmacokinetic parameters of W/O/W group and T group based on whole blood data. However, the W/O/W group had significantly
decreased tacrolimus levels in the brain and kidney, and significantly increased levels in the liver and spleen compared with
the T group. These data suggest that the W/O/W emulsion is applicable as an intravenous drug carrier for local immunosuppression. 相似文献
102.
The effects of infusion of trieicosapentaenoyl-glycerol emulsion on extravascular lung water during myocardial ischemia and reperfusion in dogs 总被引:2,自引:0,他引:2
Toshio Izuoka Yutaka Kimura Tomohito Hamazaki Teruhiro Tamura Shuji Kitashiro Tetsuro Sugiura Toshimitsu Jikuhara Toshiji Iwasaka 《Lipids》1997,32(1):109-114
To test the effects of eicosapentaenoic acid (EPA) infusion on pulmonary edema induced by coronary ligation and reperfusion,
extravascular lung water (EVLW) was measured in situ by the thermal-dye double indicator dilution method in dogs. In the control group of five dogs, 30 mL of a 10% soybean oil
emulsion was infused through a leg vein. One hour after infusion, the left anterior descending coronary artery below the first
diagonal branch was ligated for 15 min and then reperfused for 30 min. In the EPA group, six dogs were similarly treated with
an emulsion of a 10% trieicosapentaenoyl-glycerol (90% pure). EVLW, pulmonary capillary wedge pressure, mean pulmonary artery
pressure, mean blood pressure, and cardiac index were measured before and 15 min after coronary ligation, and 15 min and 30
min after coronary reperfusion. There were no significant differences in the hemodynamic indices between the two groups. EVLW
significantly increased up to two times of baseline during coronary ligation in the control group (P< 0.05) and more during reperfusion (P<0.01), whereas EVLW did not increase in the EPA group. In conclusion, EPA inhibited EVLW accumulation and may be useful for
ameliorating one of the ischemia-reperfusion-induced complications, pulmonary edema. 相似文献
103.
Y. F. Gu Y. Ro T. Kobayashi H. Harada 《Metallurgical and Materials Transactions A》2005,36(3):577-582
In an effort to enhance ductility and strength of Cr-base alloys, a series of Cr-Ru alloys with Ru contents ranging from 3
to 30 at. pct were made to study their microstructure evolution and mechanical properties. The microstructure of the alloys
with 6 to 20 at. pct Ru showed signs of a eutectic structure. However, no corresponding eutectic reaction is indicated in
the published Cr-Ru phase diagram. The yield strength of the Cr-Ru alloys increased with increasing Ru content at both room
temperature and 1200 °C. The tensile ductility of Cr-3 at. pct Ru is about 1.5 pct at room temperature, while the alloys containing
6 at. pct or more Ru showed zero tensile elongation. The deformation mechanisms of the Cr-Ru alloys are discussed in terms
of the microstructure and fracture behavior.
This article is based on a presentation made in the symposium entitled “Beyond Nickel-Base Superalloys,” which took place
March 14–18, 2004, at the TMS Spring meeting in Charlotte, NC, under the auspices of the SMD-Corrosion and Environmental Effects
Committee, the SMD-High Temperature Alloys Committee, the SMD-Mechanical Behavior of Materials Committee, and the SMD-Refractory
Metals Committee. 相似文献
104.
A review is given of recent theoretical work on the superfluid dynamics of trapped Bose gases at finite temperatures, where there is a significant fraction of non-condensate atoms. One can now reach large enough densities and collision cross-sections needed to probe the collective modes in the collision-dominated hydrodynamic region where the gas exhibits characteristic superfluid behavior involving the relative motions of the condensate and non-condensate components. The precise analogue of the Landau-Khalatnikov two-fluid hydrodynamic equations was recently derived from trapped Bose gases, starting from a generalized Gross-Pitaevskii equation for the condensate macroscopic wavefunction and a kinetic equation for the non-condensate atoms. 相似文献
105.
New Point Estimates for Probability Moments 总被引:2,自引:0,他引:2
There are many areas of structural safety and structural dynamics in which it is often desirable to compute the first few statistical moments of a function of random variables. The usual approximation is by the Taylor expansion method. This approach requires the computation of derivatives. In order to avoid the computation of derivatives, point estimates for probability moments have been proposed. However, the accuracy is quite low, and sometimes, the estimating points may be outside the region in which the random variable is defined. In the present paper, new point estimates for probability moments are proposed, in which increasing the number of estimating points is easier because the estimating points are independent of the random variable in its original space and the use of high-order moments of the random variables is not required. By using this approximation, the practicability and accuracy of point estimates can be much improved. 相似文献
106.
Shimizu N. Harada Y. Miyamoto N. Hosoya M. Goto E. 《Electron Devices, IEEE Transactions on》1989,36(6):1175-1181
The fundamental characteristics are described of the quantum flux parametron (QPF), measured by a method in which the output signals of the QFP are detected with a DC SQUID. The DC SQUID linearly and continuously converts the output current of the QFP to voltage, allowing the output signal of the QFP to be measured as the voltage of the DC SQUID. The fundamental characteristics of the QFP have been experimentally confirmed in detail 相似文献
107.
Keiro Tokaji Takeshi Ogawa Yukio Harada 《Fatigue & Fracture of Engineering Materials & Structures》1987,10(4):281-289
Abstract— The growth characteristics of small fatigue cracks were investigated under rotary bending in a high tensile strength steel, and the critical crack length above which linear elastic fracture mechanics (LEFM) is applicable was evaluated systematically from the results of the present study and previous studies in which two steels having different microstructures and strengths were used. It is found that the critical crack length extends over two regions each exhibiting different growth mechanisms. These regions of microstructurally small cracks and mechanically small cracks are found to be a unique function of the microstructural unit size and the yield strength of the materials, respectively. Therefore, using these relationships, it is possible to estimate the critical crack length for a given material. 相似文献
108.
Monoclonal antibodies (MAbs) raised against Escherichia coli O6:H16 were screened against 15 strains of E. coli and 19 non-E. coli bacteria. A MAb-luminescence assay using MAb-5.8, which shows no cross-reactions with non-E. coli bacteria, and a photon-counting television camera were developed for rapid enumeration of E. coli O6:H16 in water. The membrane filter that retained bacteria was boiled for 5 min in a buffer and incubated with biotinylated MAb-5.8. After incubation with streptavidin-peroxidase conjugate, it was reacted with luminol-based reaction mixture. Luminous image and light intensity of the filter was recorded with a Biocell Counter. Levels of E. coli O6 higher than 7 x 10(3) CFU were detected by the MAb-luminescence assay when E. coli O6 was spotted onto the membrane filter. The sample that contained E. coli O6:H16 was filtered through a membrane filter, and the filter that retained bacteria was incubated on a filter paper soaked with nutrient broth supplemented with 0.5% NaCl at 37 degrees C for 6 h. The number of light emission points on the filter correlated well with initial E. coli O6:H16 counts within the range of 1 to 3 x 10(2) CFU. The correlation coefficient was 0.89. 相似文献
109.
This article describes a three-dimensional shape recognition method that employs an ultrasonic distance sensor mounted on a manipulator, and its application to a manipulator control system. The principle of the method is to reconstruct an object surface numerically using both distance and orientation informations of an object. The method makes it possible to control the manipulator, to set the sensor in any position and orientation employing freedom of the manipulator, and to measure the object. The method is available for manipulator control because it can precisely assess the distance from the manipulator to the object, as well as reconstruct the object shape. Experimental results show that the newly developed method make object shape recognition easy and inexpensive. Application experiment proved that the method is effective for manipulator work due to its provision of distance information. 相似文献
110.