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981.
G Yaginuma Y Okada K Abe Y Iijima K Uesho K Kaneko M Otsutomo 《Canadian Metallurgical Quarterly》1997,45(9):1532-1538
The reconstruction of LV cavity is accomplished by suturing a patch to the viable myocardium to exclude the infarcted area from the high LV pressures. However, there is no clear guideline to estimate the size of patch used for LV reconstruction. We have designed a new method to determine the correct patch size, and applied it in 5 cases. The suture line of the patch is at the junction of contractile (functional) and infarcted portions of LV. The patch size is determined by the length of AB, termed "a", as the base, where "point A" represents the junction on the LV anterior wall side, and "point B" the junction of the LV posterior wall side, from RAO 30 degrees projection of the left ventriculogram obtained by cardiac catheterization. In LV aneurysm, we designed the patch in the range of a/2 < l < or = pi a/2, where patch length on RAO 30 degrees is considered "l". An effort was made to reconstruct to normalize LV volume and contour by designing the patch size to be a/2 < l < a, particularly when the contractile portion was enlarged by aneurysm. On the other hand, in post AMI VSD, LV contractile portion is not enlarged in early stage. Therefore, the patch was designed in the range of a < l < or = pi a/2 to maintain LV volume. Postoperative LV volume can be calculated prior to surgery, by using the lengths of the designed patch. Postoperative analysis indicated that the actual LV volume and contour were almost identical to our estimation. This method is very useful in planning the patch size for LV reconstruction. 相似文献
982.
983.
Makoto?Tokuda Tsutomu?MashimoEmail author Jahirul?Islam?Khandaker Yudai?Ogata Yoji?Mine Shinya?Hayami Akira?Yoshiasa 《Journal of Materials Science》2016,51(17):7899-7906
We report the effect of a strong gravitational field on oriented crystalline perovskite-type manganese oxide La1?x Sr x MnO3 (LSMO). The perovskite-type manganese oxides La1?x Sr x MnO3 (LSMO) have been investigated for giant magnetoresistance (GMR) by controlling the hole-doping level (x). A strong gravitational field can change in crystalline state and the enhancement of usual diffusion. We subjected oriented crystalline La1?x Sr x MnO3 with different grain and grain-boundary (GBs) Sr concentrations to a strong gravitational field and investigated the resulting changes in the A-site cation diffusion and physical properties of the material. Electron probe micro-analysis (EPMA) results showed appearance of the GBs where the Sr concentration was quite high compared with in other GBs. The quantitative analysis at the grain and GBs indicated that cation diffusion was more enhanced than the annealed one. The temperature dependence of the magnetic susceptibility of the gravity samples changed with the Sr concentration in the grains. The temperature dependence of the resistivity curves of the gravity sample showed several abrupt changes, which corresponded to phase transitions at the grains and GBs, which may be caused by composition changes. 相似文献
984.
Microsystem Technologies - We carried out a numerical analysis and an experimental investigation of the nonlinear resonance characteristics of an electromagnetic vibration energy harvester driven... 相似文献
985.
We propose a new boundary handling method for smoothed particle hydrodynamics (SPH). Previous approaches required the use of boundary particles to prevent particles from sticking to the boundary. We address this issue by correcting the fundamental equations of SPH with the integration of a kernel function. Our approach is able to directly handle triangle mesh boundaries without the need for boundary particles. We also show how our approach can be integrated into a position‐based fluid framework. 相似文献
986.
Sho Furutate Hitomi Nakazaki Koki Maejima Ayaka Hiroe Hideki Abe Takeharu Tsuge 《Journal of Polymer Research》2017,24(12):221
In this study, in order to explore the possibility of biosynthesizing a novel polyhydroxyalkanoate (PHA), copolymerization of 3-hydroxy-2-methylbutyrate (3H2MB) as the α-position methylated monomer and 3-hydroxyhexanoate (3HHx) as the medium-chain-length monomer was performed to obtain P(3H2MB-co-3HHx). The β-oxidation-deficient Escherichia coli LSBJ, harboring the PHA biosynthetic operon from Aeromonas caviae and the propionyl-CoA transferase gene (pct) from Megasphaera elsdenii, was cultured with feeding tiglic and hexanoic acids as the precursors for 3H2MB and 3HHx, respectively. It was observed that pct expression was highly effective to enhance the incorporation of 3H2MB into PHA. The biosynthesized PHA was composed of 3H2MB and 3HHx units only, and the 3H2MB fraction varied in the range of 36–60 mol% depending on the culture conditions. These PHAs exhibited glass transition temperatures between ?11 to ?17 °C; moreover, no melting peak was observed during analysis using differential scanning calorimetry. This study demonstrated the biosynthesis of a hitherto unreported PHA by engineering metabolic pathway in E. coli. 相似文献
987.
Makoto Kimura 《Nutrient Cycling in Agroecosystems》1997,49(1-3):153-161
Soil organic matter, roots (photosynthates) and applied organic materials (rice straw etc.) are the main sources of methane
(CH4) emitted from paddy fields. The potential CH4 production in Japanese paddy fields were estimated from chemical properties of paddy soils of respective soil series, their
acreage and thermal regimes during the rice growing period. The estimated amounts of potential CH4 production were from 24 to 54 kg-C ha-1 among 7 Districts in Japan, which are around one fifth of the amounts of CH4 emission observed from paddy fields in the world.
13CO2 uptake pot experiments were carried out three times from Aug. 8 to Sept. 25 to the treatment without rice straw applications
in 1993 and four times from June 30 to Sept. 13 to the treatments with and without rice straw applications in 1994 to estimate
the contribution of photosynthesized carbon to CH4 emission. The contribution percentages of photosynthesized carbon to the total CH4 emitted to the atmosphere were calculated to be 22% and 29-39% for the entire growth period in the treatments with and without
rice straw applications, respectively.
The relationship between the amount of CH4 emission to the atmosphere from submerged paddy soils with rice plants and the application level (0-8 g kg-1) of rice straw in soil was investigated in a pot experiment. The increase (Y) in cumulative amounts of CH4 with the increase in the application level of rice straw was formulated with a logistic curve: Y=k[a/(1 +be-cx)]; x, application level of rice straw; k, a coefficient for relative CH4 emission. Since the seasonal variations in coefficients a, b and c in the equation were also formulated as the function of
the sum of effective temperature (E, Σ (T-15); T, daily average temperature), Y from any paddy soil by any level of rice straw
application was known to be estimated by the equation: Y=k[a(E)/(1 +b(E)e-c(E)x)].
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
988.
989.
Kazuo Kondo Masahiko Okuyama Hidetoshi Ogawa Yoshimasa Shibata Yoshihiro Abe 《Journal of the American Ceramic Society》1984,67(11):c222-c223
A sintered apatite with enhanced strength was achieved by incorporating Ca O-P2 O5 /metal oxide frit. When Ba O or Al2 03 were partially substituted for Ca O in the frit composition, the sintered product was stronger because grain growth was retarded. The average bending strength of the strongest sintered apatite was 205.8 MP . 相似文献
990.
Yoshihiro Hirata Makoto Nakamura Mari Miyamoto Yosuke Tanaka Xu Hong Wang 《Journal of the American Ceramic Society》2006,89(6):1883-1889
The applied pressure and suspension height during consolidation of an aqueous suspension of nanometer-sized particles (24 nm hydroxyapatite, 30 nm SiC, 68 nm 8 mol% yttria-stabilized zirconia, 150 nm Al2 O3 , and 800 nm SiC) were continuously recorded using a pressure filtration apparatus. The packing density decreased when the particle size was less than 70 nm. The final packing density of 150−800 nm particles at 19 MPa was strongly influenced by the surface charge. However, surface charge does not affect the packing density of particles less than 70 nm. The ratio of the energy applied to two particles during consolidation to the interaction energy between two particles in a suspension was correlated to the packing density. The low packing density of 20−30 nm particles was improved by steric stabilization. The estimated thickness of the dispersant layer adsorbed on the particle surfaces was less than 1 nm and nearly independent of the molecular weight of the dispersants. When the applied pressure was released, the height of the consolidated cake increased because of the release of the elastic strain stored in the dispersant layer. 相似文献