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排序方式: 共有7330条查询结果,搜索用时 15 毫秒
61.
62.
This paper proposes a novel power cycle system composed of chemical recuperative cycle with CO2–NG (natural gas) reforming and an ammonia absorption refrigeration cycle. In which, the heat is recovered from the turbine exhaust to drive CO2–NG reformer firstly, and then lower temperature heat from the turbine exhaust is provided with the ammonia absorption refrigeration system to generate chilled media, which is used to cool the turbine inlet gas except export. In this paper, a detailed thermodynamic analysis is carried out to reveal the performance of the proposed cycle and the influence of key parameters on performance is discussed. Based on 1 kg s−1 of methane feedstock and the turbine inlet temperature of 1573 K, the simulation results shown that the optimized net power generation efficiency of the cycle rises up to 49.6% on the low-heating value and the exergy efficiency 47.9%, the new cycle system reached the net electric-power production 24.799 MW, the export chilled load 0.609 MW and 2.743 kg s−1 liquid CO2 was captured, achieved the goal of CO2 and NOx zero-emission. 相似文献
63.
The effect of porous structure and surface functionality on the mercury capacity of a fly ash carbon and its activated sample has been investigated. The samples were tested for mercury adsorption using a fixed‐bed with a simulated flue gas. The activated fly ash carbon sample has lower mercury capacity than its precursor fly ash carbon (0.23 vs. 1.85 mg/g), although its surface area is around 15 times larger, 863 vs. 53 m2/g. It was found that oxygen functionality and the presence of halogen species on the surface of fly ash carbons may promote mercury adsorption, while the surface area does not seem to have a significant effect on their mercury capacity. 相似文献
64.
石灰石在煤气化过程中的催化和固硫作用 总被引:1,自引:1,他引:1
基于CaO在煤气化中的催化和固硫作用,以及石灰石加热分解的性质,石灰石有可能作为煤气化过程中的催化剂和固硫剂。本文根据国内外对石灰石在煤燃烧和煤气化中作用的研究,从石灰石结构、Ca/C,Ca/S,可能的反应机理等几个方面进行了介绍和分析,并指出需进一步研究的内容。 相似文献
65.
66.
Combustion tests were carried out with Minto coal in combination with three different limestones in the University of British Columbia (UBC) pilot scale (152 mm square x 7.3 m tall) circulating fluidized bed combustion (CFBC) unit. Operating conditions were chosen to be typical of those employed in large-scale CFBC power boilers. Recycling of fine particles captured by the secondary cyclone was found to be of considerable importance in increasing sulphur capture, enhancing combustion efficiency and reducing the amount of calcium sulphide in the solids residues. NOx emissions increased as the Ca:S ratio increased. Local gas concentrations inside the reactor were strongly influenced by the core-annulus solids distribution patterns which characterize circulating fluidized beds. 相似文献
67.
68.
In this paper we evaluate two alternative CCS technologies at a coal-fired power plant from an investor's point of view. The first technology uses CO2 for enhanced oil recovery (EOR) paired with storage in deep saline formations (DSF) and the second merely stores CO2 in DSF. The paper updates and improves on an earlier publication by Tzimas et al. (2005). For projects of this type there are many sources of risk, three of which stand out: the price of electricity, the price of oil and the price of carbon allowances. In this paper we develop a general stochastic model that can be adapted to other projects such as enhanced gas recovery (EGR) or industrial plants that use CO2 for either EOR or EGR with CCS. The model is calibrated with UK data and applied to help understand the conditions that generate the incentives needed for early investments in these technologies. Additionally, we analyse the risks of these investments. Investments with EOR and secondary DSF storage can only be profitable (NPV > 0) when there is a high long-term equilibrium price for oil of more than $56.38/barrel. When the investment decision can be made at any time, i.e. there is an option value, then the trigger value for optimal investment is significantly higher. 相似文献
69.
《Computer Languages, Systems and Structures》2014,40(2):53-72
Smart cards are portable integrated devices that store and process data. Speed, security and portability properties enable smart cards to have a widespread usage in various fields including telecommunication, transportation and the credit card industry. However, the development of smart card applications is a difficult task due to hardware and software constraints. The necessity of the knowledge of both a very low-level communication protocol and a specific hardware causes smart card software development to be a big challenge for the developers. Written codes tend to be error-prone and hard to debug because of the limited memory resources. Hence, in this study, we introduce a model driven architecture which aims to facilitate smart card software development by both providing an easy design of smart card systems and automatic generation of the required smart card software from the system models. Differentiating from the previous work, the study in here contributes to the field by both providing various smart card metamodels in different abstraction layers and defines model-to-model transformations between the instances of these metamodels in order to support the realization of the same system on different smart card platforms. Applicability of the proposed methodology is shown for rapid and efficient application development in two major smart card frameworks: Java Card and ZeitControl Basic Card. Lessons learned during the industrial usage of the architecture are also reported in the paper. Finally, we discuss how the components of the architecture can be integrated in order to provide a domain-specific language for smart card software. 相似文献
70.
J. N. Armor 《Catalysis Letters》2007,114(3-4):115-121
Perspectives are offered for reducing the impact of huge amounts of CO2 produced today from power generation and transportation vehicles. The origins of the dilemma between the world’s increasing
use of hydrocarbons as an energy source and the cogeneration of CO2 which results as a co-product are discussed. Hydrocarbons will provide much of the fuel needs for these major, global industries
for the next 20 years and meet 60% of the world’s energy demand. With the growth of both power generation and transportation
vehicles around the world, CO2 levels will continue to increase in the atmosphere. Renewables such as wind, dams, and biomass will not be able to handle
all the energy demand. Technology breakthroughs are needed to reduce the world’s dependence on fossil fuels, which will be
aggravated by the drive to use more coal. Current approaches for removing CO2 are discussed as well as near term and future options with particular focus on how catalysis can offer some solutions. In
particular, solar photocatalysis based approaches offer a potentially viable energy solution. 相似文献