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1.
Enhanced Hydrogen Generation from Empty Fruit Bunches by Charcoal Addition into a Downdraft Gasifier
Hydrogen production by co-gasification of empty fruit bunches of palm oil could be enhanced by adding charcoal. Physiochemical characterization of raw feedstocks was performed to determine their exergy potentiality. The raw feedstocks, gasified charcoal, and the end product of produced gas were analyzed by different techniques. Gasification experiments were performed using a pilot-scale downdraft gasifier. The heating value, composition of product gas, yield of hydrogen, and exergy efficiency were used to verify the improvement of hydrogen production during the co-gasification process. Charcoal with empty fruit bunches of palm oil leads to a much higher yield of hydrogen than lower charcoal ratios or solely empty fruit bunches. This enhanced hydrogen fuel can contribute to future energy demand. 相似文献
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Johan M. Ahlstrm Alberto Alamia Anton Larsson Claes Breitholtz Simon Harvey Henrik Thunman 《国际能源研究杂志》2019,43(3):1171-1190
The demand for biofuels and biochemicals is expected to increase in the future, which will in turn increase the demand for biomass feedstock. Large gasification plants fueled with biomass feedstock are likely to be a key enabling technology in a resource‐efficient, bio‐based economy. Furthermore, the costs for producing biofuels and biochemicals in such plants could potentially be decreased by utilizing inexpensive low‐grade residual biomass as feedstock. This study investigates the usage of shredded tree bark as a feedstock for the production of biomethane in the GoBiGas demonstration plant in Gothenburg, Sweden, based on a 32 MWth industrial dual fluidized bed gasification unit. The plant was operated with bark feedstock for 12 000 hours during the period 2014 to 2018. Data from the measurement campaign were processed using a stochastic approach to establish the plant's mass and energy balances, which were then compared with operation of the plant with wood pellets. For this comparison, an extrapolation algorithm was developed to predict plant performance using bark dried to the same moisture content as wood pellets, ie, 8%w.b. Plant operation with bark feedstock was evaluated for operability, efficiency, and feedstock‐related cost. The gas quality achieved during the test period was similar to that obtained for operation with wood pellets. Furthermore, no significant ash sintering or agglomeration problems were observed more than 750 hours of operation. The calculated biomass‐to‐biomethane efficiency is 43% to 47% (lower heating value basis) for operation with wet bark. However, the predicted biomass‐to‐biomethane efficiency can be increased to 55%–65% for operation with bark feedstock dried to 8% moisture content, with corresponding feedstock costs in the range of 24.2 to 32.7 EUR/MWh; ie, a cost reduction of about 40% compared with wood pellets. 相似文献
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《Ceramics International》2022,48(10):13869-13879
Durability of the refractory liner located in an entrained-flow gasifier is one of the main factors affecting the efficiency and cost of gasification process. This study investigates the corrosion mechanism of phosphate added high-chrome refractories in a commercial entrained-flow gasifier and the effect of phosphate additives on the improvement of service life combining thermodynamic simulation calculations. The microstructures, chemical compositions, and mineral phases of the corroded samples were analyzed by scanning electron microscopy (SEM and EDS) and X-ray powder diffraction (XRD). The results demonstrated that chemical corrosion mainly occurred at the slag-matrix interface and the junction of aggregates and matrix regions. Complex spinel solid solutions were formed at the slag-refractory interface. Phosphate additives decomposed into gaseous products (such as O2, P2O3) and diffused into the interior of refractories at or close to the slag-refractory interface, not only causing an oxidizing environment but also increasing the phosphate contents in the interior of refractories. Phosphate additives in the infiltration layer occupied the gaps between crystal grains of (Cr, Al)2O3 solid solutions, reduced the infiltration of silicate phases, and absorbed Ca and Na in the slag, which subsequently increased the viscosity of the slag. 相似文献
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以天溪煤制油分公司灰熔聚气化炉的生产运行为例,分析了对入炉原料煤的指标要求,介绍了灰熔聚气化炉设备结构及流化床的物料循环机理,分析了灰熔聚气化炉在不同的分布板气速、中心管气速、氧气浓度条件下的运行状况。工业运行结果表明,首套加压灰熔聚气化炉生产运行稳定,且能满足相关地区就地取材的要求。 相似文献
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Influence of ash agglomerating fluidized bed reactor scale‐up on coal gasification characteristics 下载免费PDF全文
Yuncai Song Jie Feng Yalong Jia Wenying Li Yitian Fang 《American Institute of Chemical Engineers》2014,60(5):1821-1829
To study the influence of fluidized‐bed reactor scale‐up on coal gasification characteristics, a model of the ash agglomerating fluidized‐bed reactor has been developed using an equivalent reactor network method. With the reactor network model, the scale‐up effects of a gasifier were studied in terms of the characteristics of the chemical reactions in the jet zone, the annulus dense‐phase zone and the freeboard zone. Results showed that the changes occurred in the inequality proportion of the volume of the jet zone during the reactor scale‐up. Taking into consideration the utilization of a portion of the backflow gas, the expansion of the jet zone volume and the coal particle residence time, the temperature of the jet zone was increased from 1592 to 1662 K. Also, both the annulus dense‐phase zone temperature and the freeboard zone temperature decreased, causing subsequent decrease in the carbon conversion efficiency. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1821–1829, 2014 相似文献
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介绍了水煤气两段炉生产过程中参数报警的原因及处理措施,并介绍了安全联锁的设置部位及其作用。 相似文献
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