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1.
We present a laser item identification system (L2IS), installed in a real facility on trial, that is capable of automatically monitoring all transfers of uranium hexafluoride (UF6) cylinders between different process areas. Each cylinder has a unique ‘fingerprint’ represented by the 3D micro-structure of its surface which remains intact even under extreme environmental conditions. L2IS automatically identifies each cylinder through exploring the 3D frontal surface acquired by the laser scanner. The system is composed of a portable unit (operated in attended mode) and a fixed installed unit (operated without inspector presence). The efficiency and accuracy of our identification system were evaluated on a large dataset acquired during several years including a full year of field testing.  相似文献   
2.
This paper presents a number of ongoing projects that will be valuable to the development of technologies for digital theatre and performance. This paper describes an EU ACTS project called RESOLV which develops an integrated system to capture real 3D environments using laser and video. Current research on motion tracking, statistical behaviour modelling and simulation is presented, and possible applications, both for visual augmentation and audio generation, are discussed. The projects presented were not originally designed in the domain of theatre and performance, however their results and output seem to be well suited to be applied in this area.  相似文献   
3.
The dialysis patient is prone to elevations in the calcium phosphorus product and hyperparathyroidism, which contributes to valvular and vascular calcification. We present the case of a young lady on chronic dialysis that developed mitral calcification complicated by severe mitral stenosis, caseous calcification and retinal embolization. She subsequently required mitral valve replacement.  相似文献   
4.
Exposure to sunlight is the major cause of skin cancer. Ultraviolet radiation (UV) from the sun causes damage to DNA by direct absorption and can cause skin cell death. UV also causes production of reactive oxygen species that may interact with DNA to indirectly cause oxidative DNA damage. UV increases accumulation of p53 in skin cells, which upregulates repair genes but promotes death of irreparably damaged cells. A benefit of sunlight is vitamin D, which is formed following exposure of 7-dehydrocholesterol in skin cells to UV. The relatively inert vitamin D is metabolized to various biologically active compounds, including 1,25-dihydroxyvitamin D3. Therapeutic use of vitamin D compounds has proven beneficial in several cancer types, but more recently these compounds have been shown to prevent UV-induced cell death and DNA damage in human skin cells. Here, we discuss the effects of vitamin D compounds in skin cells that have been exposed to UV. Specifically, we examine the various signaling pathways involved in the vitamin D-induced protection of skin cells from UV.  相似文献   
5.
ABSTRACT

The object of the present paper is to explore the possibility of using simulated annealing procedures to determine multi-speed three phase windings. It is limited to the very simple case of p/2p polarities. The program has yielded the very well known solutions; thus, research may proceed towards more difficult problems.  相似文献   
6.
Hydration behaviour of synthetic saponite was examined by X-ray powder diffraction simulation at various relative humidities (RH). The basal spacing of the Ca-saponite increased stepwise with increase in RH. The (00l) reflections observed reflect single or dual hydration states of smectite. Quasi-rational, intermediate, or asymmetrical reflections were observed for all XRD patterns and reflecting heterogeneity of the samples, especially along the transition between two hydration states.  相似文献   
7.
Intermetallic particles, Al3Ti and Al3Zr were formed in Al–5mass%Ti and Al–5mass%Zr alloys, respectively, by centrifugal casting, in order to create functionally graded materials (FGMs). At present, no information is available on the influence of the amount of intermetallics on the electrochemical properties of these alloys.In this paper, the corrosion resistance of Al/Al3Ti and Al/Al3Zr FGMs was investigated by open-circuit measurements, potentiodynamic polarization and electrochemical impedance spectroscopy. Results suggests that the corrosion resistance of the FGMs is affected by galvanic effects between the intermetallic particles and the metallic matrix. Lower centrifugal forces resulted in an improvement of the electrochemical properties.  相似文献   
8.
Sodium borohydride as a fuel for the future   总被引:2,自引:0,他引:2  
In a time of unprecedented change in environmental, geopolitical and socio-economic world affairs, the search for new energy materials has become a topic of great relevance. Sodium borohydride, NaBH4, seems to be a promising fuel in the context of the future hydrogen economy. NaBH4 belongs to a class of materials with the highest gravimetric hydrogen densities, which has been discovered in the 1940s by Schlesinger and Brown. In the present paper, the most relevant issues concerning the use of NaBH4 are examined. Its basic properties are summarised and its synthesis methods are described. The general processes of NaBH4 oxidation, hydrolysis, and monitoring are reviewed. A comprehensive bibliometric analysis of the NaBH4 publications in the energy field opens the discussion for current perspectives and future outlook of NaBH4 as an efficient energy/hydrogen carrier. Despite the observed exponential increase in the research on NaBH4 it is clear that further efforts are still necessary for achieving significant overchanges.  相似文献   
9.
A single-stage closed-cycle helium gas cryogenerator, capable of cooling between 77 K and 300 K, has been installed on the 4-circle neutron diffractometer at CIRUS. The cryo-tip assembly has been incorporated directly on the ϕ-circle of the full-circle crystal orienter in place of the goniometer head used in room temperature experiments. The salient features of this low-temperature attachment and its performance are discussed.  相似文献   
10.
Copper tubes are considered as material of choice for most domestic and institutional plumbing requirements. However, to a few instances problems have arisen which were shown to involve microbiological activity. The BRITE/EURAM Project “New Types of Corrosion Impairing the Reliability of Copper in Potable Water Caused by Microorganisms” (Contract-No. BREU-CT 91-0452) was launched to examine the interactions between microorganisms and their secreted products and a copper tube surface involving a cross-disciplinary consortium. A review of this project is reported in this contribution. Based upon chemical analysis of biofilms from failed copper tubes, it was possible to develop model biopolymers of defined composition and well characterised surface adsorption properties to establish suitable electrochemical test procedures. Culture biopolymers showing similar chemical compositions could be produced from a range of copper-pitting-associated bacteria. It was possible to demonstrate cation selective behaviour by layers of these relevant model and culture biopolymers. Two linked copper electrodes, one hare and the other coated with a cation selective biopolymer, were shown to establish a corrosion element. The covered areas acted as the cathode whilst the bare areas were anodic. This was also seen in single metal samples with disrupted polymer coatings giving “bare” patches. In anodic areas the corrosion follows a chloride induced mechanism leading to repassivation of the surface. This could also be demonstrated in the original potable water taken from an institutional building affected by Microbially Influenced Corrosion (MIC). Sulphate ions inhibit this expected passivation process. The basic corrosion process appears to follow the chloride model, but this can become overshadowed by the effects of additional anions such as sulphate and bicarbonate.  相似文献   
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