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81.
Motion of an antiviral compound in a rhinovirus capsid under rotational symmetry boundary conditions
A molecular dynamics (MD) simulation of a complex of a rhinovirus protein shell referred to as a "capsid" and an anti-rhinovirus drug, WIN52084s, was performed under the rotational symmetry boundary conditions. For the simulation, the energy parameters of WIN52084s in all-atom approximations were determined by ab initio calculations using a 6-31G* basis set and the two-conformational two-stage restricted electrostatic potential fit method. The motion of WIN52084s and the capsid was focused on in the analysis of the trajectory of the simulation. The root mean square deviations of WIN52084s from the X-ray structure were decomposed to conformational, translational, and rotational components. The translation was further decomposed to radial, longitudinal, and lateral components. The conformation of WIN52084s was rigid, but moving in the pocket. The easiest path of motion for WlN52084s was on the longitudinal line, providing a track for the binding process required of the anti-rhinovirus drug to enter the pocket. The conformation of the pocket was also preserved in the simulation, although the position of the pocket in the capsid fluctuated in the lateral and radial directions. 相似文献
82.
Toshikazu Takeda Toshiki Okamoto Akira Inoue Shinya Kosaka Hideaki Ikeda 《Annals of Nuclear Energy》2006
The anisotropic scattering effect to keff is studied for UO2 and MOX fueled BWR assemblies. The anisotropic scattering effect increases the assembly k∞ by 0.44% Δk for the UO2 assembly with 0% void fraction, and by 0.21% Δk for the MOX assembly with 0% void fraction. This is because the anisotropic scattering effect flattens the intra-assembly thermal flux, and the absorption rate in the surrounding water gap is decreased, but the absorption rates in the MOX fuel rods are increased compared to the UO2 rods. Therefore, the total decrease in absorption rates in the UO2 assembly is relatively large, and the k∞ is increased in the UO2 assembly. The dependence of the anisotropic scattering effect on the void fraction is investigated, and the significant difference of 0.62% Δk/k is found for the 0% and the 80% void fractions. The BWR assemblies with Gd rods are also considered. Furthermore, the usefulness of the transport cross section is investigated, and it is found that the transport cross section gives reasonable anisotropic scattering effect, though not satisfactory. 相似文献
83.
An improved method for sulfur chemiluminescence detection in combination with capillary gas chromatography was established. The method was applied to the analysis of a sulfur-containing antiasthma drug, S-1452, and its nine metabolities in human plasma. The high selectivity and sensitivity of the method allowed accurate quantitation of trace levels of these compounds in human plasma with no interferences from the biological components present. To enable stable measurements and maintain reproducibility over a long period, the performance characteristics of a commercially available instrument were investigated. The gas seal in the injection port was found to easily corrode through interaction of the sulfur analyte with the metal gas seal. To prevent this, a disk made from an alloy of platinum and gold (60:40) was mounted on the gas seal. The reproducibility of the measurement was improved remarkably by using the disk. The use of compressed air of high purity significantly lowered the signal-to-noise ratio. The optical filter was kept clean by using a nickel catalyst to trap ozone in place of copper manganese oxide (CuMn2O4). These improvements raised the sensitivity and selectivity with the lower quantitation limits of 0.5-1.0 ng/mL in human plasma. 相似文献
84.
Grain-growth inhibition in an Fe-10 mass pct Ni alloy, which was continuously cooled from a melt, was studied at 1673 K in
the presence of primary deoxidation products of ZrO2 or MgO particles. The mean grain size and grain-size distribution in a cross section were measured as a function of holding
time for up to 240 minutes. The grain growth was strongly inhibited by the inclusion particles and was influenced by the dissolved
Zr. In the Zr deoxidation, the number of particles per unit area (N
A) ranged from 80 to 650 mm−2, the ZrO2 particle size (
) varied from 1.1 to 1.6 μm, and the dissolved Zr level was below 1800 mass ppm. In the Mg deoxidation, the particle-number density was 90 to 270 mm−2, the MgO particle size was 1.1 to 1.7 μm, and the dissolved Mg level was below 20 mass ppm. In a logarithmic plot of the ratio of limiting mean grain diameter (
) to the mean particle diameter (
) against the volume fraction of particles (f
V), both the
value for a given f
V value, which ranged from 0.014 to 0.074 pct, and the slope were significantly lower than that predicted from the two-dimensional
relation
=(4/π) · f
V
/−1
, i.e., Zener’s limit. This discrepancy is discussed in light of the fraction of particles at the grain boundaries measured experimentally.
Normal grain growth was confirmed from the grain-size distribution observed as a function of holding time, which was best
described by the log-normal distribution. 相似文献
85.
A. Matsubara K. Kawasaki H. Inaba S. Miyawaki O. Ishikawa T. Hata T. Kodama 《Journal of Low Temperature Physics》1999,114(3-4):349-370
We have measured the viscosity, , and the slip length, , of normal and superfluid
3
He using a torsional oscillator with a thick sample space. We coated the oscillating surface with 2.5 layers of
4
He film to study how the
4
He thin film changes the scattering mechanism of
3
He quasiparticles at the cell wall at 5 bar and 21 bar. In the normal phase, the temperature dependence of the viscosity was changed a little by the
4
He film at 21 bar but no change was observed at 5 bar. The slip length was enhanced by
4
He coating at 5 bar. This enhancement indicates the increase of specularity of
3
He quasiparticles scattering at the oscillating surface. On the other hand, a reduction of the slip length was observed at 21 bar. In the superfluid phase, the temperature dependence of supports the existence of Andreev reflection even with
4
He film on the surface at 5 bar and 21 bar. 相似文献
86.
H Shimada K Nakajima T Ochiai Y Koide SI Okazumi H Matsubara A Takeda Y Miyazawa M Arima K Isono 《Canadian Metallurgical Quarterly》1998,5(4):871-874
The significance of serum p53-Abs in patients with esophageal squamous cell carcinoma was determined. Examination of clinicopathological features and assessment of tumor marker sensitivities of carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag) and CYFRA21-1 were performed. Thirty-three (58%) of 57 patients were positive for serum p53-Abs, however, no relation with cancer progression existed. Fourteen of the 33 sero-positive patients revealed normal levels of all tumor markers tested. Thus, serum p53-Abs appears to be a useful marker for the detection of esophageal squamous cell carcinoma. 相似文献
87.
Y Nagai T Azuma M Funauchi M Fujita M Umi M Hirano T Matsubara S Ueno 《Canadian Metallurgical Quarterly》1998,157(1):52-59
This study examined the effect of thyrotrophin-releasing hormone (TRH) administration on thermoregulation in the newborn. Twin lambs were either delivered near-term by caesarean section or born vaginally at term. Colonic temperature, O2 consumption, CO2 production, breathing and heart rates, plus plasma thyroid hormone and nonesterified fatty acid (NEFA) concentrations and thermogenic activity (i.e. GDP binding) of brown adipose tissue (BAT) were measured. In caesarean section delivered lambs colonic temperature decreased rapidly after birth, a response that was greater in the group designated for TRH treatment, in which colonic temperature fell to below 36.0 degrees C at 80 min of life, prior to TRH administration. At this age colonic temperature had been restored to a mean of 38.70 degrees C in controls. TRH had no influence on the composition or thermogenic activity of BAT. The incidence of shivering was not influenced by TRH, but treated lambs maintained a higher rate of O2 consumption and ventilation compared with controls after colonic temperature had been restored to 38.56 degrees C. TRH appeared to promote fat oxidation as O2 consumption remained unchanged and CO2 production declined by a greater rate in treated lambs, resulting in a lower respiratory quotient compared to controls. Heart rate and plasma concentrations of NEFA increased following TRH administration although this did not result in values greater than controls. Normothermic lambs born vaginally had BAT with a greater thermogenic activity, higher plasma thyroid hormone and NEFA concentrations compared with caesarean section delivered lambs, but a thermogenic response was not observed to TRH despite a rise in thyroid hormone concentrations. In conclusion, TRH can improve thermoregulation, an effect that could be linked to an increase in fat oxidation. 相似文献
88.
Yoshio Iwai Shinji Miyamoto Hideaki Ikeda Yasuhiko Arai Shigetoshi Kobuchi Yuji Sano 《Polymer Engineering and Science》1993,33(6):322-327
The mutual diffusion coefficients for styrene-butadiene rubber(SBR)-n-nonane systems were measured using a sorption apparatus with a quartz spring at 100 and 130°C for mass fractions of n-nonane ranging from 0 to 0.16. The mutual diffusion coefficients were correlated with good agreement by the free-volume theory. 相似文献
89.
The optimal periodic control of a single nonisothermal CSTR in which a single reaction, a parallel reaction or a consecutive reaction is taking place is studied. Both the feed rate and the heat transfer between the reactor content and the immersed coil are periodically controlled. Utility consumption and conversion of the raw material into the waste are included in the performance index together with conversion into the desired product. The results indicate a respectable improvement in the reactor performance. 相似文献
90.
It has been reported that, compared with TAG, DAG suppresses postprandial hypertriacylglycerolemia and reduces visceral fat
levels in experimental animals and humans. To clarify the mechanism responsible for these beneficial effects, we compared
the lymphatic transport of 1,3-DAG, a major isomer of DAG, and TAG in rats. Male SD rats, after insertion of a cannula into
the thoracic duct, were given 1,3-di[1-14C]oleoylglycerol or tri[1-14C]oleoylglycerol via a stomach tube. The 24-h receovery of the radioactivity from 1,3-di[14C]oleoylglycerol in the lymph was slightly but significantly lower than that from tri[14C]oleoylglycerol (81.3±1.0 vs. 86.5±1.2%, respectively). However, in the first 1-h interval after administration, the recovery
of radioactivity from 1,3-dioleoylglycerol was almost half of that from trioleoylglycerol (17.5±2.0 vs. 31.1±1.4%). The amount
of TAG and phospholipids secreted into the lymph was significantly lower 1 h after the administration of 1,3-dioleoylglycerol
compared with that after the administration of trioleoylglycerol. More than 90% of the radioactivity recovered in the lymph
in the first 3 h was distributed in the TAG fraction for both 1,3-dioleoylglycerol and trioleoylglycerol. These results suggest
that slower lymphatic transport of 1,3-DAG compared with TAG could be a factor in the suppression of postprandial hypertriacylglycerolemia.
The possibility that the slower lymphatic transport of DAG contributes to the antiobesity action observed in the feeding of
1,3-DAG cannot be excluded. 相似文献