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81.
This paper makes a comparative study of urban planning system between Wuhan and Macao,including the legislation system,administration system,and operation system of planning.Meanwhile,it also explores how to improve the current planning systems.  相似文献   
82.
This paper describes the implementation of the Refined Triggering Graph (RTG) method for active rule termination analysis and provides an evaluation of the approach based on the application of the method to a sample active application. The RTG method has been defined in the context of an active-deductive, object-oriented database language known as CDOL (Comprehensive, Declarative, Object Language). The RTG method studies the contents of rule pairs and rule cycles in a triggering graph and tests for: (1) the successful unification of one rule's action with another rule's triggering event, and (2) the satisfiability of active rule conditions, asking whether it is possible for the condition of a triggered rule to evaluate to true in the context of the triggering rule's condition. If the analysis can provably demonstrate that one rule cannot trigger another rule, the directed vector connecting the two rules in a basic triggering graph can be removed, thus refining the triggering graph. An important aspect in the implementation of the method is the development of a satisfiability algorithm for CDOL conditions. This paper presents the tool that was developed based on the RTG method, describing how techniques from constraint logic programming are integrated with other techniques for testing the satisfiability of rule triggering conditions. The effectiveness of the approach within the context of a sample application is also addressed.  相似文献   
83.
The learning of complex relationships can be decomposed into several neural networks. The modular organization is determined by prior knowledge of the problem that permits to split the processing into tasks of small dimensionality. The sub-tasks can be implemented with neural networks, although the learning examples cannot be used anymore to supervise directly each of the networks. This article addresses the problem of learning in a modular context, developing in particular additive compositions. A simple rule allows defining efficient training, and combining, for example, several Supervised-SOM networks. This technique is important because it introduces interesting generalizations in many modular compositions, permitting data fusion or sequential combinations of neural networks. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
84.
85.
We report two children who presented with cough and shortness of breath 7-8 months after a matched sibling stem cell transplant (SCT) for chronic myelogenous leukemia and myelodysplastic syndrome, respectively. Pulmonary function tests (PFTs) revealed severe airways obstruction (AO). However, radiographic investigations showed no serious abnormalities in the early phase and open lung biopsy revealed only mild lymphocytic bronchiolitis and bronchiolitis obliterans consistent with pulmonary graft-versus-host disease (GVHD). Despite administration of bronchodilators and various immunosuppressive agents obstructive lung disease progressed to pulmonary failure in patient 1, whereas stabilization of the clinical course was observed in patient 2. Serial PFTs were the best predictor of the clinical course in contrast to radiographic and histologic findings. It is concluded that PFTs should be performed repeatedly in pediatric patients after allogeneic SCT with the aim of diagnosing GVHD-associated AO in the subclinical phase. Progressive post-transplant AO necessitates prompt initiation of intensive immunosuppressive therapy in order to stop the underlying immunopathologic process even in the absence of severe radiographic and histologic findings.  相似文献   
86.
We report the existence of high resistance to Melarsoprol and low resistance to Suramin in 11 Trypanosoma rhodesiense species. They were isolated from humans in the Tete province, Mozambique, and kept in mice at the Maputo National Health Institute. The preliminary results obtained with Suramin administered intracranially, are also reported.  相似文献   
87.
Cu clusters of diameters less than 10 nm were selected as models to study oxidation as a function of size, chemical composition, and structure. The investigations were performed with high-resolution electron microscopy. It was shown that beginning with multiply twinned particles as stable structures for particles with diameters less than 5 nm and of cuboctahedra for larger particles, in the transitional state between pure metal and oxide both states can coexist within the same particle; this latter can be proved by HRTEM. It was also demonstrated that this is due to incorporating distortions as step dislocations within grain boundaries which can be shown in electron micrographs of high resolution better than 0.18 nm after image processing. The creation of sub-oxides with less reactivity than the pure metal clusters could also be demonstrated leading to morphologies which are different from those of the pure metal. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
88.
Amorphous Ni-Zr powders have been prepared by mechanical alloying of elemental crystalline powders. The glass-forming range has been determined in detail at different milling intensities. Depending on the milling conditions, at least partial crystallization of the formerly amorphous material can occur from 66 to 75 at% Ni, due to a temperature rise during milling at high intensity. In comparison with isothermal annealing experiments at various temperatures on completely amorphous powder, a relation between milling temperature and milling time is shown. This confirms the similarity of the amorphization process during mechanical alloying with the solid-state interdiffusion reaction in alternating crystalline multilayers.  相似文献   
89.
Emulsions now find a wide range of applications in industry and daily life. In the pharmaceutical industry lipophilic active ingredients as well as many nutritional products such as vitamins are often formulated in the dispersed phase of oil‐in‐water emulsions. Emulsions can be produced with different mechanical emulsification techniques. In the following review, the process of rotor‐stator systems and disc systems are compared to other popular mechanical emulsification systems. On the basis of experimental results from the authors' laboratory, a discontinuous gear‐rim dispersing system, discontinuous disc system, and a continuous high pressure system are compared with regard to their attainable mean droplet diameter and drop size distribution in an oil‐in‐water emulsion. It can be shown that dissolver discs with a very simple geometry attain very small mean droplet diameters and a very narrow droplet size distribution, comparable to the emulsions obtained with established rotor‐stator systems such as gear‐rim dispersers.  相似文献   
90.
In nuclear medicine therapies, people working with beta radiators such as (90)Y may be exposed to non-negligible partial body doses. For radiation protection, it is important to know the characteristics of the radiation field and possible dose exposures at relevant positions in the working area. Besides extensive measurements, simulations can provide these data. For this purpose, a movable hand phantom for Monte Carlo simulations was developed. Specific beta radiator handling scenarios can be modelled interactively with forward kinematics or automatically with an inverse kinematics procedure. As a first investigation, the dose distribution on a medical doctor's hand injecting a (90)Y solution was measured and simulated with the phantom. Modelling was done with the interactive method based on five consecutive frames from a video recorded during the injection. Owing to the use of only one camera, not each detail of the radiation scenario is visible in the video. In spite of systematic uncertainties, the measured and simulated dose values are in good agreement.  相似文献   
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