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1.
A questionnaire to evaluate the needs of dialytic patients and the burden that these have on the health service and staff, was formulated by the nurses. The results showed how the patient's case history indicate, significantly, not only personal and subjective aspects (e.g. interpersonal relationships), but also how they construct their relationships with the hospital and its service (including the hospital staff). This opens up certain reflections on what role communication and information play within the hospital structure.  相似文献   
2.
xtreme ltra iolet ithography (EUVL) seeks to apply radiation in a wavelength region centered near 13 nm to produce microcircuits having feature sizes 0.1 micron or less. A critical requirement for the commercial application of this technology is the development of an economical, compact source of this radiation which is suitable for lithographic applications. A good candidate is a laser-plasma source, which is generated by the interaction of an intermediate intensity laser pulse (up to 1012 W/cm2) with a metallic target. While such a source has radiative characteristics which satisfy the needs of an EUVL source, the debris generated during the laser-target interaction strikes at the economy of the source. Here, we review the use of concepts and computer modeling, originally developed for hypervelocity impact analysis, to study this problem.  相似文献   
3.
Electrical capacitance volume tomography (ECVT) is a recently-developed technique for real-time, non-invasive 3D monitoring of processes involving materials with strong contrasts in dielectric permittivity. This work is first application of the method to visualization of water flow in soil. We describe the principles behind the method, and then demonstrate its use with a simple laboratory infiltration experiment. 32 ECVT sensors were installed on the sides of an empty PVC column. Water was poured into the column at a constant rate, and ECVT data were collected every second. The column was then packed with dry sand and again supplied with water at a constant rate with data collected every second. Data were analyzed to give bulk average water contents, which proved consistent with the water supply rates. Data were also analyzed to give 3D images (216 voxels) allowing visualization of the water distribution during the experiments. Result of this work shows that water infiltration into the soil, wall flow, progress of the unstable wetting front and the final water distribution are clearly visible.  相似文献   
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Modern day competition in manufacturing requires producers to rely heavily on continuous quality improvement methods to remain competitive. Reliability being a significant element of quality is the primary means for making design and process improvements. Current reliability allocation methods to establish improvement goals focus on cost reduction but do not necessarily give due consideration to the relative impact of component cost. A method is presented that uses warranty burden rates as a weighting factor to develop component improvement goals. A sample application is given to illustrate application of the method.  相似文献   
7.
The quasicrystalline structures of alloys with nominal compositions of Al72Ni13.4Co14.6 and Al72.3Ni7.8Co19.8 were characterized by X-ray diffraction, transmission electron microscopy and scanning electron microscopy. For catalytic application, the solids were leached with an alkaline NaOH solution and tested at 373 K with two model reactions under atmospheric pressure: hydrogenation of crotonaldehyde and acetonitrile. The catalytic activities of these leached alloys were compared to that of a Raney nickel reference catalyst. Catalysts prepared from quasicrystals showed high catalytic activities and high selectivities towards butanal (in crotonaldehyde hydrogenation) and ethylamine (in acetonitrile hydrogenation).  相似文献   
8.
A discussion of the effects of Bioglass® powder crystallisation on the in vitro bioactivity in simulated body fluid (SBF) is presented.Starting from Bioglass® powder, different glass–ceramics were obtained by thermal treatments between 580 °C and 800 °C, with variable crystallisation content (from 10 to 92 wt%). All samples (glass and glass–ceramics) showed apatite formation at their surface when immersed in SBF. In case of the glass and the samples with lowest crystallinity, the first step of apatite formation involved a homogenous dissolution followed by an amorphous calcium phosphate (CaP) layer precipitation. For the samples with a high crystallisation content, heterogeneous dissolution occurred. For the first time, the Stevels number of the amorphous phase is used to explain the possible dissolution of the crystalline phase present in materials with a similar chemical composition of the Bioglass®. All samples presented at 21 days of immersion in SBF B-type hydroxycarbonate apatite crystals.  相似文献   
9.
In this paper, a set covering problem is considered. The problem of concern is the simplification of data representation for large-scale Boolean-valued data structures by generating a minimum cover for one of the two data classes. The cover is based on a “neighborhood” concept which can be specified in terms of simple parameters. An optimal set of neighborhoods or a minimum cover is determined which corresponds to the search for an optimal solution for a data representation requiring the minimum number of parameters.  相似文献   
10.
Pattern measurements of a low-sidelobe horn antenna   总被引:1,自引:0,他引:1  
The power pattern of a corrugated horn antenna designed for low sidelobes was measured to levels 90 dB below the main beam maximum in both theE- andH-planes. The measured patterns were found to be in good agreement with theoretical predictions.  相似文献   
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