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941.
Rats with lesions of the perirhinal cortex and a control group were required to find a platform in 1 corner of a white rectangle and in the reflection of this corner in a black rectangle. Test trials revealed that these groups were able to integrate information regarding the shape of the pool and the color of its walls (black or white) to identify the correct location of the platform. A clear effect of the perirhinal cortex lesions was, however, revealed using an object recognition task that involved the spontaneous exploration of novel objects. The results challenge the view that the perirhinal cortex enables rats to solve discriminations involving feature ambiguity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
942.
Coupling between pressurized gas sorption and tensile behavior was studied in several semi-crystalline polymers: a Polyethylene (PE), a Polyamide 11 (PA11) and multi-layer systems based on these two materials were tested in tension into hydrogen (30 bars) and nitrogen (30 bars) atmosphere and compared to experiments into atmospheric air. Gaseous environments were shown to have no noticeable deleterious effect influence on the modulus and the yield stress in all materials. This study provides a first basis for the mechanical design of hydrogen distribution applications.  相似文献   
943.
For the last two decades, economic development in Reunion Island has led to major structural changes. The latter have been characterized by an increase in energy demand per person. This demand is mostly related to a high population growth (1.55% per year). Reunion currently has 833,000 inhabitants. The population will rise to 1 million in 2030. Like most ultraperipheral regions of the European Union, Reunion is heavily dependent on imported fossil fuels for its energy production. The total primary energy consumption amounted to 1352 ktep in 2009 and 87.1% is imported energy. The development of various renewable energies such as solar energy, biomass, ocean energy, etc. is thus of priority concern to aim to achieve energetic independence. Just like other French overseas territories, Reunion policies have widely invested in Renewable Energy Sources (RES) since 2000. This paper aims at presenting the current status, the major achievements of policies and the future objectives in the deployment of renewable energy programmes. The perspective of a net zero energy island versus the pressure of the population is analysed. The barriers to penetration of RES in a small-scale territory are also discussed.  相似文献   
944.
Iron ore pellets abrade during handling and produce dust. This study was conducted to determine what factors affect pellet dustiness, and whether dustiness can be related to the abrasion index. Factors studied included bed depth within a straight grate furnace; pellet chemistry; firing temperature; coke breeze addition; and tumble index. Abrasion indices for all pellet samples ranged from 1.9–5.0% (20 samples) and from 7.1–27.5% (5 samples). Pellets were dropped in an enclosed tower, which enabled the collection of airborne particles generated during pellet breakdown. The quantity of airborne particles generated by each pellet type was 10–100 mg/kg-drop, or 50–500 mg/kg over five drops through the tower. Pellet dustiness was predominantly affected by pellet chemistry and by pellet firing temperature. Results showed a nearly 21% increase in dustiness for every percent decrease in firing temperature – this was based on a typical firing temperature of 1280°C. Pellet dustiness was regressed to the pellet abrasion index (for AI < 5%), which yielded a correlation coefficient of 0.22. These results show that, although AI is one of the best indicators of fired pellet quality and can indicate high levels of dust, it could not explain the dustiness of good quality pellets.

The second paper (Iron Ore Pellet Dustiness Part II) explains the relationship between AI and dust for good-quality pellets; and compares fines generation between pellets fired in Straight-Grate (Traveling Grate) and Grate-Kiln furnaces.  相似文献   
945.
Transmission electron microscopy observations and thermoelectrical property measurements (electrical conductivity, Seebeck coefficient and thermal conductivity) at room temperature have been completed on two fully dense polycrystalline p-type bismuth–tellurium–antimony alloy samples. It is shown that the presence of antimony oxide-based nanosized inclusions (controlled as to volume fraction and size distribution), homogeneously dispersed in the surrounding matrix leads to a dimensionless figure of merit (ZT) of ~1.3 at room temperature. For comparison, when such inclusions are missing the ZT value is only 0.6.  相似文献   
946.
Public indoor swimming pools are a very popular type of sports facility. They need to ensure good indoor air quality and thermal comfort of the occupants (TCO) while reducing their energy consumption. The objectives of this study are to develop a numerical code, based on the zonal method; to investigate the indoor airflow patterns; and to determine the TCO in the indoor swimming pool. The numerical simulation, performed using the TRNSYS software (version 17), is validated against intensive field measurements, carried out in the public indoor swimming pool located at Bishop’s University (Sherbrooke, Quebec, Canada), of the temperature, velocity, and relative humidity of the air as well as the surface temperature of the walls, ceiling, and floor. The developed code is then used to study the indoor flow patterns and to evaluate the TCO using three indexes: the humidex chart, the predicted mean vote (PMV), and the predicted percentage of dissatisfied (PPD). The results show a hot-humid rather uncomfortable atmosphere is prevailing in the occupied parts of the studied indoor swimming pool. The calculated airflow rates show that, due to the position of the ventilation inlets and outlets, most of the ventilation air circulates in the upper part of the building causing an insufficient air renewal in the occupied parts of the studied indoor swimming pool.  相似文献   
947.
The synthesis of ω-dihydroxylated polystyrene oligomers was performed by free radical polymerization of styrene in the presence of α-thioglycerol. Monitoring styrene and α-thioglycerol concentration evolution by gas chromatography during a batch process allowed us to determine the value of the thiol transfer constant. Due to this high value (Cs = 6.2), a fast drift of the batch composition was observed. In order to control the ratio of thiol/styrene during the reaction, a model was developed by simulating the addition of the thiol in the batch during styrene polymerization. ω-dihydroxylated functionalized oligomers, with a low polymolecularity index and a controlled molar mass were then prepared. Gel permeation chromatography and MALDI-TOF mass spectrometry measurements proved the validity of our model.  相似文献   
948.
Generation of relevant and robust models for neurological disorders is of main importance for both target identification and drug discovery. The non-cell autonomous effects of glial cells on neurons have been described in a broad range of neurodegenerative and neurodevelopmental disorders, pointing to neuroglial interactions as novel alternative targets for therapeutics development. Interestingly, the recent breakthrough discovery of human induced pluripotent stem cells (hiPSCs) has opened a new road for studying neurological and neurodevelopmental disorders “in a dish”. Here, we provide an overview of the generation and modeling of both neuronal and glial cells from human iPSCs and a brief synthesis of recent work investigating neuroglial interactions using hiPSCs in a pathophysiological context.  相似文献   
949.
Unsaturated lipids are prone to get oxidized through a sequence of reactions known as lipid oxidation. From a phenomenon considered at the beginning as a mere chemical process and described by the triptych of initiation, propagation, and termination, the vision of lipid oxidation has progressively evolved to further integrate the physical dimension of the phenomenon. Despite tremendous research efforts, however, this sequence of reactions is not yet well understood, especially in lipid dispersions where many facts are still inexplicable and unpredictable under the current paradigm. Here, the aim is to suggest that the main reason why a better understanding has not already been achieved is that the reactional network is not yet organized in a coherent spatiotemporal framework. The novel concepts and hypotheses proposed in this article may help redirecting a significant part of research efforts toward the establishment of a spatially and temporally resolved model of oxidation in dispersed lipids. Practical Application : Predicting how oxidation spreads in lipid dispersions represents a goal of crucial importance for academia but also for industry. Such prediction models would indeed greatly help food manufacturers prevent oxidation by using the most adapted antioxidative strategies for their specific products. To achieve such an objective, it is proposed that the first thing to do is to go beyond the extremely reductive and narrow framework in which this chemical process has been locked in. Indeed, while lipid dispersions are composed of a multitude of lipid colloids, researchers usually consider oxidation at the sole level of an individual droplet or membrane. Instead, lipid oxidation is advocated as a dynamic trafficking of chemical species within large communities of different colloidal objects such as droplets, membranes, or micelles dispersed in water—a system that dubbed “colloidal ecosystem”. This might represent a scale complementary to the scales of individual colloids or molecules that were the sole consideration so far to try to represent lipid oxidation. Only then can one hope to effectively apply modeling and “omics” approaches, as is explained in more details in this article.  相似文献   
950.
The dynamics of soda-lime-silica glass grain melting is investigated experimentally using a nonintrusive technique. A cylindrical alumina crucible is filled with glass cullet and placed into a furnace illuminated by an X-ray source. This glass granular bed is gradually heated up to 1100°C, leading to its melting and the generation of a size-distributed population of bubbles rising in the molten glass. An image processing algorithm of X-ray images of the cullet bed during melting allows the characterization of bubbles size distribution in the crucible as well as their velocity. The introduction of tin dioxide μ-particles in the glass matrix before melting enhances the texture of the images and makes possible the determination of the bubble-induced molten glass velocity field by an optical flow technique. The bubble size distribution can be fitted by a log-normal law, suggesting that it is closely related to the initial size distribution in the cullet bed. The liquid motion induced by the bubbles in Stokes' regime is strongly affected by the flow confinement and the determination of bubble rising velocity along its trajectory unveils the existence of local tiny temperature fluctuations in the crucible. Overall, the measuring techniques developed in this work seem to be very promising for the improvement of models and optimization of industrial glass furnaces.  相似文献   
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