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This paper describes the results of site investigations, monitoring, stability analyses, and soil-pipe interaction modeling of a built-up slope located near Pineto (Abruzzo Province, Central Italy), where a gas pipeline exploded on March 6th, 2015, due to heavy rains inducing slope movements. The slope is formed by OC clay, covered with an upper 10- to 14-m-thick clayey-sandy silt colluvial layer. The explosion in the upper portion of the slope caused extensive damage to existing buildings and threatened human lives. Soon after the event, a site investigation and monitoring program was carried out. A detailed topographic survey and hydrological data were analyzed in order to characterize possible critical rainfall events. The stability of the slope was analyzed both in pre- and in post-explosion conditions. The profiles of the DMT horizontal stress index K D helped to identify multiple slip surfaces. Then, the results of the site investigation and stability analyses were used to implement a simplified finite element model aimed to describe the soil-pipeline interaction, taking into account the role of the observed wrinkle in the pipeline. The numerical simulations reveal the crucial role played by the slope movements, and by the wrinkle as well, in inducing the collapse of the pipe.  相似文献   
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It has been said that nuclear energy is an important option for especially developing countries to satisfy their increasing energy demand. However, it will be difficult to deploy first of a kind nuclear power plant in developing countries because extensive safety demonstration has to be conducted in industrialized countries. On the other hand, it will be essential to present rigid proof of reliable operational experience to develop proper understanding of the safety features of new reactor systems among the people around the demonstration plant sites. One of the ways to solve the issue is to integrate existing technologies supported by a great deal of data and experience into a new reactor design. Based on the consideration, a small-sized district heating reactor system based on the pressurized water reactor (PWR) technologies combined with the fuel concept of high temperature gas cooled reactors (HTGRs) has been studied. The purpose of the combination of these two existing concepts is to take the best advantages of both excellent operational experience of PWRs and the integrity of HTGR fuel, coated particle fuel, against fission products release even at high temperature. We expect that this approach will help create a breakthrough to the current stagnation of nuclear power deployment.  相似文献   
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Retention of the stationary phase of aqueous–aqueous polymer phase systems is improved by a spiral column configuration which utilizes the radially acting centrifugal force along the spiral pitch to retain the heavier phase in the outer portion and the lighter phase in the inner portion of the spiral channel. For the separation of proteins which has low mass transfer rates, the system needs further modification of the separation channel to interrupt the laminar flow and enhance mixing of the two phases.  相似文献   
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The increase in electric power consumption in industry has led to the development of modern distribution systems such as control centers having high kVA ratings and high prospective fault current. In such a situation, the improvement of the system usefulness such as reliability and cost effectiveness is the essential requirement. An index is presented to evaluate the system usefulness using the cost effectiveness for fault protection in a system of given bank kVA. The index is estimated on four different system structures of control centers, including one which utilizes Permanent Power Fuses (PPF). It is presented that the PPF combined with molded case circuit breaker in main circuit effectively improves the cost effectiveness in control centers with high fault current. Operating principles of the PPF and the control center utilizing the PPF are briefly outlined.  相似文献   
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Polymethylmethacrylate (PMMA)-based bone cement is widely used for the fixation of artificial joints. However, it is not considered a bioactive material because it lacks the ability to induce a direct bond with bone. In order to improve the long-term stability of cemented fixations, the development of bioactive bone cements is desirable. An essential requirement of a bioactive material includes the induction of bone-like apatite on its surface within the in vivo environment. Previously, we prepared bioactive PMMA-based bone cements by a modification with water-soluble calcium salts and alkoxysilane. Because spatial design may enhance apatite formation on bioactive material surfaces in vivo, we aimed to evaluate the effect of spatial design on apatite formation on modified PMMA-based bone cements in simulated body fluid (SBF). We found that an appropriate spatial design shortened the induction period for the apatite deposition on the modified bone cements. It is expected that osteoconduction would be enhanced in spontaneously created gap between the cement and the host bone leading to tight integration.  相似文献   
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Despite advances in medicine, cardiac disease remains an increasing health problem associated with a high mortality rate. Maladaptive cardiac remodeling, such as cardiac hypertrophy and fibrosis, is a risk factor for heart failure; therefore, it is critical to identify new therapeutic targets. Failing heart is reported to be associated with hyper-ubiquitylation and impairment of the ubiquitin–proteasome system, indicating an importance of ubiquitylation in the development of cardiac disease. Ubiquitylation is a post-translational modification that plays a pivotal role in protein function and degradation. In 1995, homologous to E6AP C-terminus (HECT) type E3 ligases were discovered. E3 ligases are key enzymes in ubiquitylation and are classified into three families: really interesting new genes (RING), HECT, and RING-between-RINGs (RBRs). Moreover, 28 HECT-type E3 ligases have been identified in human beings. It is well conserved in evolution and is characterized by the direct attachment of ubiquitin to substrates. HECT-type E3 ligase is reported to be involved in a wide range of human diseases and health. The role of HECT-type E3 ligases in the development of cardiac diseases has been uncovered in the last decade. There are only a few review articles summarizing recent advancements regarding HECT-type E3 ligase in the field of cardiac disease. This study focused on cardiac remodeling and described the role of HECT-type E3 ligases in the development of cardiac disease. Moreover, this study revealed that the current knowledge could be exploited for the development of new clinical therapies.  相似文献   
9.
Collapse of micrometer-sized cavitation bubbles near a rigid boundary   总被引:1,自引:0,他引:1  
The interaction of cavitation bubbles with a rigid boundary and its dependence on the distance between bubble and boundary is investigated experimentally. Individual cavitation bubbles, with a maximum radius of 150?μm, are generated by using pulsed high-intensity focused ultrasound. Observations are made with high-speed photography with framing rates of up to 200?million frames per second and exposure time of 5?ns, and the spatial resolution is in the order of a few micrometers. The significant parameter of this study is the non-dimensional stand-off parameter, γ, defined as the distance between the ultrasound focus and the rigid boundary scaled by the maximum bubble radius. Both the velocity of the liquid jet developed during bubble collapse and the maximum pressure of the shock wave emitted during bubble rebound show a minimum for γ?≈?1 and a constant value for γ?>?3. The maximum jet velocity is slightly smaller than the corresponding values obtained in the case of millimeter-sized bubbles and ranges from 80?m/s (at γ?≈?1) to 130?m/s (for γ?>?3). No jet formation was observed for γ?>?3. The shock wave pressure, measured at a distance of 5?mm from the emission center, ranges from 0.2?MPa (at γ?≈?1) to 0.65?MPa (for γ?>?3). These values are an order of magnitude smaller than those obtained in the case of millimeter-sized bubbles. The shock wave duration is almost independent of γ at a value of about 75?ns. For large γ values (γ?>?3), a large percentage of the bubble energy (up to 60?%) is transformed into the mechanical energy of the shock wave emitted during bubble rebound but, for γ?≈?1, the conversion efficiency decreases to 30?%. Independent of the relative distance between bubble and rigid boundary, the shock pressure decays proportionally to r ?1 with increasing distance r from the emission center. The results are discussed with respect to cavitation damage and collateral effects in pulsed high-intensity focused ultrasound surgery.  相似文献   
10.
The in-flight nitridation of MoSi2 powder particles was attempted in an argon-nitrogen induction plasma, with and without tail gas quenching. The inductive power level, reactor pressure, plasma-gas composition, and quantity of quench gas, as well as the species of quench gas, were investigated to obtain substantial nitridation of the MoSi2 powder particles. Under investigated conditions, ∼2.8 wt% of nitrogen was incorporated into the MoSi2 powder particles.  相似文献   
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