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331.
REMORA aims at offering an agile robotic solution for manufacturing tasks done on very large parts (e.g., very long and slender parts found in aeronautic industries). For such tasks, classical machine tools are designed at several tens of meters. Both their construction and operation require huge infrastructure supports. REMORA is a novel lightweight concept and flexible robotic solution that combines the ability of walking and manufacturing. The robot is a mobile manufacturing system which can effectuate operations with good payload capacity and good precisions for large workspace applications. This new concept combines parallel kinematics to ensure high stiffness but low inertia and mobile robotics to operate in very large workspaces. This results in a machining center of new generation: (1) agile manufacturing system for large workspace applications, (2) heavy load and good precisions, (3) 5-axis machining and 5-axis locomotion/clamping, (4) self-reconfigurable for specific tasks (workspace and force), and (5) flexible and multifunctional.  相似文献   
332.

Objective

To evaluate the utility of amide proton transfer (APT) imaging in estimating the Gleason score (GS) of prostate cancer (Pca).

Materials and methods

Sixty-six biopsy-proven cancers were categorized into four groups according to the GS: GS-6 (3 + 3); GS-7 (3 + 4/4 + 3); GS-8 (4 + 4) and GS-9 (4 + 5/5 + 4). APT signal intensities (APT SIs) and apparent diffusion coefficient (ADC) values of each GS group were compared by one-way analysis of variance with Tukey’s HSD post hoc test.

Results

The mean and standard deviation of the APT SIs (%) and ADC values (×10?3 mm2/s) were as follows: GS-6, 2.48 ± 0.59 and 1.16 ± 0.26; GS-7, 5.17 ± 0.66 and 0.92 ± 0.18; GS-8, 2.56 ± 0.85 and 0.86 ± 0.17; GS-9, 1.96 ± 0.75 and 0.85 ± 0.18, respectively. The APT SI of the GS-7 group was highest, and there were significant differences between the GS-6 and GS-7 groups and the GS-7 and GS-9 groups (p < 0.05). The ADC value of the GS-6 group was significantly higher than each value of the GS-7, GS-8, and GS-9 groups (p < 0.05), but no significant differences were obtained among the GS-7, GS-8, and GS-9 groups.

Conclusion

The mean APT SI in Pca with a GS of 7 was higher than that for the other GS groups.
  相似文献   
333.
Neutron nuclear data of Xe isotopes have been evaluated in the energy region, including the resolved resonance one, from 1 keV to 20 MeV by using the theoretical nuclear reaction models. The phenomenological optical model potential was employed to calculate the total cross section for natural Xe with the coupled-channels method. The cross sections for channels of capture, (n, 2n), (n, p) and (n, α) reactions were calculated and compared with available experimental results including recently measured data. The elastic scattering angular distributions and particle emission spectra were calculated, although there is no experimental information available. Reaction cross sections of evaluated libraries were considered for comparison with the calculated results. The presently calculated cross sections reproduce better the available experimental data.  相似文献   
334.
Hepatocyte-specific Phosphatase and tensin homolog (Pten)-knockout (KO) mice exhibit hepatic lesions analogous to non-alcoholic steatohepatitis (NASH). 1,8-cineole is a monoterpene oxide and it has several biological effects including hepatoprotective effects. In this study we revealed that 1,8-cineole ameliorates NASH of Pten KO mice. Pten KO mice were assigned to a control group without any medication or to a 1,8-cineole group injected with 50 mg/kg i.p. twice per week for eight weeks. At eight weeks, livers from each group were processed to measure triglyceride (TG) content, gene expression analysis, western blot analysis, and histological examination including Oil red O staining. 1,8-cineole ameliorated hepatic steatosis in Pten KO mice, revealed by TG content and Oil red O staining. Moreover, 1,8-cineole downregulated collagen 1a1 expression and improved liver fibrosis. Thus, 1,8-cineole has potential as a candidate to treat NASH by inactivating the Akt/PI3-kinase pathway.  相似文献   
335.
To reduce refractory damage during steelmaking, precise control of slag composition is important. Usually, the formation and decomposition rates of interfacial layer are considered to be rate‐controlling steps. The influence of the interfacial layer on the dissolution rate was investigated. The reagents were mixed and sintered to make an oxide that simulated the interfacial layer. The sample was added to molten slag stirred by Ar gas, and the dissolution rate was determined from the change in slag composition. The results revealed the importance of the effects of the density and composition of the interfacial layer on the dissolution rate.  相似文献   
336.
The microwave irradiation was performed using a compacted Cu powder under different oxygen partial pressures. After reaching about 600 K, an abrupt temperature rise and drop occurred. The abrupt temperature drop is caused by both sintering of Cu powder particles and growing of surface oxide film. The magnitude of the abrupt temperature drop decreased with increasing oxygen partial pressure. The temperature then remained constant (steady state), gradually increased or exhibited a secondary significant increase. The magnitude of the temperature rise after abrupt temperature drop increased with increasing oxygen partial pressure. The microwave heating behavior of the compacted Cu powder depended on the type and thickness of the surface oxide film and also on the type and volume fraction of the gas occupying the vacant spaces between the Cu powder particles.  相似文献   
337.
The mechanical behaviors of Cu–Sn alloy wire specimens processed by the newly proposed method of rotary draw bending are systematically investigated, mainly by considering the relationship between the Vickers hardness (HV) on the cross section and the compressive residual energy during draw bending. It was found that during draw bending, the HV was lower than that of the specimen subjected to wire drawing, particularly on the inside of the bend, and it was confirmed that the softening induced by plastic deformation is promoted by increasing the compressive residual energy. The changes in HV and compressive residual energy were closely related. Consequently, there was a large difference in the hardness distributions on the inside and outside of the bend, and the mechanical properties of the wire specimen changed greatly during draw bending. Additionally, the change in the texture resulting from draw bending obtained by the finite element method (FEM) analysis of stress and the measured change in the texture showed good qualitative agreement.  相似文献   
338.
When the human UDP-galactose transporter 1 gene (hUGT1) was introduced into tobacco plants, the plants displayed enhanced growth during cultivation, and axillary shoots had an altered determinate growth habit, elongating beyond the primary shoots and having a sympodial growth pattern similar to that observed in tomatoes at a late cultivation stage. The architecture and properties of tissues in hUGT1-transgenic plants were also altered. The leaves had an increase in thickness, due to an increased amount of spongy tissue, and a higher content of chlorophyll a and b; the stems had an increased number of xylem vessels and accumulated lignin and arabinogalactan proteins (AGPs). Some of these characteristics resembled a gibberellin (GA)-responsive phenotype, suggesting involvement of GA. RT-PCR-based analysis of genes involved in GA biosynthesis suggested that the GA biosynthetic pathway was not activated. However, an increase in the proportion of galactose in polysaccharide side chains of AGPs was detected. These results suggested that because of higher UDP-galactose transport from the cytosol to the Golgi apparatus, galactose incorporation into polysaccharide side chains of AGP is involved in the gibberellin response, resulting in morphological and architectural changes.  相似文献   
339.
We used a single-particle soot photometer (SP2) to measure the mass of individual black carbon (BC) particles down to ~ 0.5 fg by means of laser-induced incandescence with an intra-cavity, continuous-wave laser. The incandescence of nine different types of BC samples was investigated to provide a physical basis for choosing appropriate BC materials for SP2 calibration. We estimated the vaporization temperatures of these BC samples from the spectral dependence of incandescence at the limit of the small size parameter x, for which spectral dependence of emissivity is known a priori. The vaporization temperatures differed by less than 2.2% among the samples. For the x < 1 regime of particle size, the peak amplitude of the incandescence signal measured by the SP2 was linearly proportional to the particle mass. The slopes of such linear proportionality were positively correlated with | (m 2 -1)/(m 2 +2)|, where the m is the complex refractive index of the BC particle. For particles in which x > 1, the rate of increase in the peak amplitude of the incandescence signal with increasing particle mass was negatively correlated with the compactness of particle shape, consistent with the theoretical prediction of emissivity, which accounts for particle shape. The incandescence–BC mass relationships were similar between fullerene soot and ambient soot sampled in Tokyo, thus suggesting that fullerene soot is a suitable calibration standard for SP2 measurements of ambient soot.  相似文献   
340.
Surface relief (SR) gratings with a molecularly oriented structure and pure polarization hologram were fabricated on a photo-cross-linkable liquid crystalline copolymer using a 325-nm laser with various two-beam polarization modes. For intensity holography, the polarization information from the two beams simultaneously provided the molecular motion and molecular reorientation; the SR height reached up to 186 nm and the concave area revealed a molecular reorientation when the exposing beams were linearly polarized. In contrast, SR formation was negligible for polarization holography when molecular reorientation due to the polarization modulation was observed. The resulting polarization gratings changed the polarization properties of the diffraction beams, and their diffraction efficiency was reached 24%, which agreed with theoretical expectations.  相似文献   
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