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151.
We performed an analysis of published literature related to fruit and vegetable and indexed in the Web of Science®, covering the period 2000–2009. The EU27 and the USA are the two leading actors in terms of number of fruit and vegetable articles published. This paper compares their publication outputs using bibliometric methods. We assessed the fruit and vegetable species, topics (from Web of Science® categories), countries and institutions involved. The top species, topics and institutions are ranked according to their number of publications. Collaboration networks between countries were mapped to visualize the intensity of the relationships involved in international fruit and vegetable research and to obtain an overall picture of the fruit and vegetable research landscape. These results can be useful for policy makers.  相似文献   
152.
During the various carbon dioxide capture and storage (CCS) stages, an accurate knowledge of thermodynamic properties of \(\mathrm{CO}_{2}\) streams is required for the correct sizing of plant units. The injected \(\mathrm{CO}_{2}\) streams are not pure and often contain small amounts of associated gaseous components such as \(\mathrm{O}_{2}, \mathrm{N}_{2}\) , \(\mathrm{SO}_{x}, \mathrm{NO}_{x}\) , noble gases, etc. In this work, the thermodynamic behavior and transport properties of some \(\mathrm{CO}_{2}\) -rich mixtures have been investigated using both experimental approaches and molecular simulation techniques such as Monte Carlo and molecular dynamics simulations. Using force fields available in the literature, we have validated the capability of molecular simulation techniques in predicting properties for pure compounds, binary mixtures, as well as multicomponent mixtures. These validations were performed on the basis of experimental data taken from the literature and the acquisition of new experimental data. As experimental data and simulation results were in good agreement, we proposed the use of simulation techniques to generate new pseudo-experimental data and to study the impact of associated gases on the properties of \(\mathrm{CO}_{2}\) streams. For instance, for a mixture containing 92.0 mol% of \(\mathrm{CO}_{2}\) , 4.0 mol% of \(\mathrm{O}_{2}\) , 3.7 mol% of Ar, and 0.3 mol% of \(\mathrm{N}_{2}\) , we have shown that the presence of associated gases leads to a decrease of 14 % and 21 % of the dense phase density and viscosity, respectively, as compared to pure \(\mathrm{CO}_{2}\) properties.  相似文献   
153.
A simple combination of dichloro(para‐cymene)ruthenium(II) dimer, a chiral amino alcohol and isopropyl alcohol allowed for in‐situ generation of the bifunctional catalyst responsible for the transfer hydrogenation reaction of trifluoromethyl ketimines in excellent yields with high enantioselectivities (up to 93% ee). Herein, we describe the optimization, scope, limitations, and applications of the method.

  相似文献   

154.
155.
For sheet metal forming, the determination of the onset of localized necking directly influences the formability evaluation and construction of forming limit curves (FLCs). Several necking criteria in the literature have been proposed and widely used, however, there are some restrictions, e.g., some criteria are suitable for numerical methods but not for the experimental phase. In this study, numerical and experimental procedures are carried out to seek an appropriate necking criterion for the prediction of FLCs. This article begins with the FE modeling of the Marciniak test with ABAQUS. Based on the FE simulation, different necking criteria (global and local ones) are reviewed and analyzed in detail, and the FLCs for a 5086 aluminum sheet are constructed with these criteria. On the other hand, a quasi-static experimental Marciniak test is carried out to study the formability for this given sheet. With a chosen necking criterion, the limit strains are experimentally determined. The comparison between experimental and numerical results shows that the chosen necking criterion could be effective to numerically and experimentally evaluate the global formability of this aluminum alloy on the wide range of strain states.  相似文献   
156.
The issue of investment is all too often underplayed in deregulation reforms focused on market rules and de-integration measures. This presentation criticises first the optimistic approach of the theory of investment incentives through market signals when it is applied to deregulated electricity industries. The greater part of the investment in base-load and peak equipment should be made profitable by income from very high prices during peak and extreme peak periods, that raises a problem of political acceptability. The problem is then addressed in the context of the mature electricity industries in the North. Given the maturity of markets there, a number of modifications to the pure market model could be envisaged to strengthen incentives to invest, but none of them is perfect. The main way is to focus on adaptation of market rules on the supply of power at peaks and extreme peaks by considering “capacity adequacy” as a public good (with three solutions: capacity payment, reserve obligations, centralised procurement by auctioning for peak capacity). Observation of reforms suggests also the validity of some other solutions based on a limitation of the competition by allowing long-term contracts and vertical integration between production and supply. Finally the question is extended to the specific problem of developing countries characterised by irregular growth. It is argued that reforms must be designed in view of the importance of the need for investment through long-term coordination and reduction of investment risks. Indeed experiences of Latin American liberalised industries show that they have to include a number of competition-based imperfections and to allow ongoing exercise of market power in order to allow prices to rise above competition prices. The single buyer model or some variants of it appear to be good alternatives if one wishes to avoid the twists and turns of the competition paradigm. The difficulty with this model arises from the institutional conditions necessary to make it efficient and not overcostly.  相似文献   
157.
Herein, the novel concept of a solid‐state electrode materials with ionic‐liquid (IL) properties is presented. These composite materials are a mixture of electroactive matter, an electronic conductor, a solid‐state ionic conductor and a polymeric binder. The approach of a solid‐state ionic conductor combines the high safety of an IL with the nanoconfinement of such a liquid in a mesoporous silica framework, an ionogel, thus leading to a solid with liquid‐like ionic properties. The same ionic conductor is also used as a solid‐state separator to evaluate the properties of our solid‐state electrode materials in all‐solid‐state batteries. Such a concept of a solid‐state electrode material contributes to addressing the challenge of energy storage, which is one of the major challenges of the 21st century. The ionogel, along with its processability, allows a single‐step preparation of the assembly of the solid‐state electrode and solid‐electrolyte separator and can be applied without specific adaptation to present, thick electrodes prepared by the widespread tape‐casting technique. The filling of the electrode porosity by an ionogel is shown by elemental mapping using scanning electron microscopy, and is subsequently confirmed by electrochemical measurements. The ionogel approach is successfully applied without specific adaptation to two state‐of‐the‐art, positive electroactive materials developed for future‐generation lithium‐ion batteries, namely LiFePO4 and LiNi1/3Mn1/3Co1/3O2.  相似文献   
158.
Reducing the severity of injuries resulting from motor-vehicle crashes has long been a primary emphasis of highway agencies and motor-vehicle manufacturers. While progress can be simply measured by the reduction in injury levels over time, insights into the effectiveness of injury-reduction technologies, policies, and regulations require a more detailed empirical assessment of the complex interactions that vehicle, roadway, and human factors have on resulting crash-injury severities. Over the years, researchers have used a wide range of methodological tools to assess the impact of such factors on disaggregate-level injury-severity data, and recent methodological advances have enabled the development of sophisticated models capable of more precisely determining the influence of these factors. This paper summarizes the evolution of research and current thinking as it relates to the statistical analysis of motor-vehicle injury severities, and provides a discussion of future methodological directions.  相似文献   
159.

Background

This study sets out to identify risk factors for post-traumatic stress disorder (PTSD) after a road traffic accident with a view to improving prevention.

Methods

The study used a prospective cohort of road traffic accident casualties. All subjects over 15 years of age were recruited in the course of an interview conducted while they were receiving care in a hospital of the Rhône area administrative département. Six months after their accident, they answered a self-administered postal questionnaire that included the Post-traumatic Check-List Scale (PCLS) in order to evaluate PTSD. Multivariate logistic regression analysis was conducted to compare those subjects with a PCLS score of 44 or over with those with a lower score, in order to identify factors that might be associated with PTSD.

Results

592 subjects (out of 1168) returned the 6-month questionnaire and 541 completed the PCLS test. One hundred subjects had a PCLS score ≥44, suggesting PTSD, and 441 subjects did not. The factors associated with PTSD were initial injury severity, post-traumatic amnesia, the feeling of not being responsible for their accident and persistent pain 6 months after it. A lower odds-ratio was associated with users of two-wheel than four-wheel motor vehicles (OR = 0.4; 0.2–0.9).

Conclusion

Besides predictive factors for PTSD (injury severity, post-traumatic amnesia and the feeling of not being responsible for their accident), our study suggested a reduced risk of PTSD among two-wheel motor vehicle users.  相似文献   
160.
This paper is an overview of the physical mechanisms and length scales governing the propagation of wildfires. One of the objectives is to identify the physical and mathematical constraints in the modelling of wildfires when using a ??fully?? physical approach. The literature highlights two regimes in the propagation of surface fires, i.e. wind-driven fires and plume-dominated fires, which are governed by radiation and convective heat transfer, respectively. This division leads to the identification of two governing length scales: the extinction length characterising the absorption of radiation by vegetation, and the integral turbulent length scale characterising the interaction between wind and canopy. Some numerical results published during the last decade using a fully physical approach are presented and discussed with a focus on the models FIRESTAR, FIRELES, FIRETEC and WFDS. Numerical simulations were compared with experimental data obtained at various scales, from laboratory to field fires in grassland and in Mediterranean shrubland. Some perspectives are presented concerning the potential coupling between physical fire models with mesoscale atmospheric models to study the impacts of wildfires at larger scale. Some of the topics on wildfire physical modelling that need further research are identified in the conclusions.  相似文献   
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