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131.
132.
2009年,上海能源供应体系自从引入液化天然气以来,进口液化天然气对全市天然气供应总量和来源多元化做出了重要贡献。2013年,液化天然气消费在全市天然气消费总量中占比达50%,在天然气供应体系中发挥了越来越重要的作用。近年来,上海天然气市场发生了深刻变化,天然气需求增长放缓,与2013年之前十多年的两位数增长形成了鲜明对比。为了更好地理解市场的基本面,首先回顾了上海天然气消费的历史趋势,随后分析了影响需求增长的驱动因素和约束条件,以判断未来天然气需求的趋势和液化天然气在市场中扮演的角色,认为天然气需求增长的潜力主要在民用及商业领域。结合分析可能的供应选择,其结论是未来液化天然气将继续作为上海天然气供应体系的主力气源,同时提供市场急需的灵活性以保障高峰时段的用气需求。 相似文献
133.
Cold recovery during regasification of LNG part one: Cold utilization far from the regasification facility 总被引:2,自引:0,他引:2
The paper deals with cold recovery during LNG regasification. The applications analyzed pertain to the use in deep freezing agro food industry and in space air conditioning facilities in commercial sector (Supermarkets and Hypermarkets) of cold recovered from the regasification process. 相似文献
134.
Seungwon Park Jaekyeong Yoo Seung Ju Han Ji Hwan Song Eo Jin Lee In Kyu Song 《International Journal of Hydrogen Energy》2017,42(22):15096-15106
A series of mesoporous nickel–boron–alumina xerogel (x-NBA) catalysts with different boron/nickel molar ratio (x = 0–1) were prepared by an epoxide-driven sol–gel method. The effect of boron/nickel molar ratio on the catalytic activities and physicochemical properties of nickel–boron–alumina xerogel catalysts was investigated in the steam reforming of liquefied natural gas (LNG). All the mesoporous x-NBA catalysts showed similar surface area. Introduction of boron increased interaction between nickel and support. In addition, introduction of boron into x-NBA catalysts reduced methane activation energy and increased nickel surface area. Promotion of boron had a positive effect on the catalytic activity due to the increase of adsorbed methane and nickel surface area. The amount of adsorbed methane and nickel surface area exhibited volcano-shaped trends with respect to boron/nickel molar ratio. LNG conversion and hydrogen yield increased with increasing the amount of adsorbed methane and with increasing nickel surface area. Among the catalysts, 0.3-NBA, which retained the largest amount of adsorbed methane and the highest nickel surface area, showed the best catalytic performance. It was also revealed that x-NBA catalysts showed strong coke resistance during the steam reforming reaction. 相似文献
135.
COOLCEP (cool clean efficient power): A novel CO2-capturing oxy-fuel power system with LNG (liquefied natural gas) coldness energy utilization 总被引:1,自引:0,他引:1
A novel liquefied natural gas (LNG) fueled power plant is proposed, which has virtually zero CO2 and other emissions and a high efficiency. The plant operates as a subcritical CO2 Rankine-like cycle. Beside the power generation, the system provides refrigeration in the CO2 subcritical evaporation process, thus it is a cogeneration system with two valued products. By coupling with the LNG evaporation system as the cycle cold sink, the cycle condensation process can be achieved at a temperature much lower than ambient, and high-pressure liquid CO2 can be withdrawn from the cycle without consuming additional power. Two system variants are analyzed and compared, COOLCEP-S and COOLCEP-C. In the COOLCEP-S cycle configuration, the working fluid in the main turbine expands only to the CO2 condensation pressure; in the COOLCEP-C cycle configuration, the turbine working fluid expands to a much lower pressure (near-ambient) to produce more power. The effects of some key parameters, the turbine inlet temperature and the backpressure, on the systems' performance are investigated. It was found that at the turbine inlet temperature of 900 °C, the energy efficiency of the COOLCEP-S system reaches 59%, which is higher than the 52% of the COOLCEP-C one. The capital investment cost of the economically optimized plant is estimated to be about 750 EUR/kWe and the payback period is about 8–9 years including the construction period, and the cost of electricity is estimated to be 0.031–0.034 EUR/kWh. 相似文献
136.
A novel energy and cost effective transport chain for stranded natural gas utilized for power production with CO2 capture and storage is developed. It includes an offshore section, a combined gas carrier and an integrated receiving terminal. The combined carrier will transport liquid carbon dioxide (LCO2) and liquid nitrogen (LIN) outbound, where natural gas (NG) is cooled and liquefied to LNG by vaporization of LIN and LCO2 onboard the carrier. The same carrier is used to transport the LNG onshore, where the NG can be used for power production with CO2 capture. The combined carrier consists of 10 cylindrical tanks with a diameter of 9.2 m and varying lengths from 14 to 40 m. The total ship volume is 13,000 m3. Assuming 85% capture rate of the CO2, the maximum ship utilization factor (SUF) is 63.4%. Due to the combined use of the storage tanks, the SUF is decreased with 1.4% points to 62%. The ship is equipped with a bi-directional submerged turret loading for anchoring and loading of NG and unloading of CO2. Two ships can deliver NG to and remove CO2 from a 400 MWnet power plant, and still obtain continuous production of LNG offshore without intermediate storage. The investment cost for each gas carrier is 40 million EUR giving total transport cost of 16.9 EUR/tonne LNG. The cost for the offshore transfer system is 6.6 million EUR per tonne LNG, whereas the cost for onshore storage and loading system is 3.1 and 0.8 million EUR per tonne LNG, respectively. The total specific costs for the ship transport, including onshore storage, loading shipping and offshore unloading are 27.5 EUR per tonne LNG for a roundtrip of 5 days, including voyage, production of LNG, unloading, connecting and berthing. 相似文献
137.
我国首批9F燃机捆绑招标电厂——深圳前湾燃机电厂3台9F燃气-蒸汽联合循环机组已于2007-03-30全部成功投产。投产后3台机组的主要性能指标全部达到并超过合同的要求。9F机组调峰能力强、排放低、效率高。燃气-蒸汽联合循环机组电厂不但可以提高天然气LNG站线的运行稳定性,同时可以满足电网系统对尖峰负荷机组日益增加的需求。9F级联合循环电厂在我国具备一定的生存发展空间。 相似文献
138.
LNG作为车用燃料具有安全环保和经济性的优势,LNG汽车的优势和前景已得到了普遍认可。但是,我国目前现有的LNG加气站的数量远不能适应L N G汽车交通运输发展的需要。由于液化模式和技术等的不同,LNG加气站相比传统的汽柴油加油站的类型更加多样化。从LNG车用加注市场全产业链的角度,可以将LNG加气站的运营模式分为六种。它们的技术和工艺流程都不相同,因此影响其成本的主要因素也不同。可以综合考虑每种模式的使用条件和成本影响因素,来选择合适的运营模式。但是专用液化模式应是发展LNG加气站的主要方向,只用这样才能向市场提供大量廉价的LNG,进而形成跨地域的LNG加注网络。随着时间的推移,LNG车用燃料市场规模将会不断扩大,综合运用这六种LNG加气站运营模式才能满足日益增长的LNG车用燃料的市场需求。 相似文献
139.
140.
Mehdi Mehrpooya Mohammad Mehdi Moftakhari Sharifzadeh Mahsa Rajabi Mortaza Aghbashlo Meisam Tabatabai Soleiman Hosseinpour Seeram Ramakrishna 《International Journal of Hydrogen Energy》2017,42(12):8486-8496
This study was aimed at proposing a novel integrated process for co-production of hydrogen and electricity through integrating biomass gasification, chemical looping combustion, and electrical power generation cycle with CO2 capture. Syngas obtained from biomass gasification was used as fuel for chemical looping combustion process. Calcium oxide metal oxide was used as oxygen carrier in the chemical looping system. The effluent stream of the chemical looping system was then transferred through a bottoming power generation cycle with carbon capture capability. The products achieved through the proposed process were highly-pure hydrogen and electricity generated by chemical looping and power generation cycle, respectively. Moreover, LNG cold energy was used as heat sink to improve the electrical power generation efficiency of the process. Sensitivity analysis was also carried out to scrutinize the effects of influential parameters, i.e., carbonator temperature, steam/biomass ratio, gasification temperature, gas turbine inlet stream temperature, and liquefied natural gas (LNG) flow rate on the plant performance. Overall, the optimum heat integration was achieved among the sub-systems of the plant while a high energy efficiency and zero CO2 emission were also accomplished. The findings of the present study could assist future investigations in analyzing the performance of integrated processes and in investigating optimal operating conditions of such systems. 相似文献