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排序方式: 共有58条查询结果,搜索用时 15 毫秒
1.
用两种水溶性树脂在碱性镁橄榄石砂上进行了试验,结果表明:镁橄榄石涛因耗酸值高,表面不规则,多孔洞等使得PAN-1型树脂无法满足使用要求,而PAN-2型树脂表现出良好的工艺性能,成功地铸造出物辙叉铸件。  相似文献   
2.
采用共沉淀法合成了锂离子正极材料LiFePO4,考察了不同合成条件对材料结构及性能的影响.研究结果表明:通过碳包覆改性后,LiFePO4的容量可明显提高,SiO2的掺杂对LiFePO4的结构没有影响.同时讨论了上述两种改性方法对材料性能的影响机制.  相似文献   
3.
马建华 《化学世界》2012,53(2):123-125
纯橄岩矿是一种用途广泛的矿物资源,浅析了纯橄岩的性质、用途及综合开发的现状。  相似文献   
4.
以磷酸亚铁锂为正极材料的锂离子电池以其高安全、高环保、低价格、长寿命、大容量等特点,将逐步取代现有铅酸电池市场,成为未来动力锂离子电池研究的热点材料。简述了几种常规合成磷酸亚铁锂方法的同时,较系统地介绍了磷酸亚铁锂材料在液相共沉淀制备方法中的研究进展,包括全液相共沉淀法和半液相共沉淀法。指出全液相法合成工艺比较简单、工艺路线较短,但是由于溶液体系中各组分沉淀速度存在差异,因而可能会导致组成的偏离和均匀性的丧失;半液相法虽然增加了工艺流程,但是可以通过控制pH、滴加速度等控制磷铁复合盐的形成,使产品呈球状,进而有助于提高磷酸亚铁锂的振实密度。  相似文献   
5.
主要对玻基橄辉岩和碱性橄榄玄武岩及其所含的尖晶石二辉橄榄岩包体的特征进行了详细研究描述,并根据这些岩石的化学成分和稀土元素含量讨论了它们的成因,根据二辉地质温度计和辉石地质温度计估算了它们的形成深度。研究结果表明:广西马山永州出露的这些基性-起基性小岩体多数为玻基橄辉岩,少数为碱性橄榄玄武岩,两者均属碱性玄武岩浆分异的产物。它们所含尖晶石二辉橄榄岩包体(Ⅰ型超镁铁质岩包体),为亏损地幔岩碎块,系上地幔部分熔融形成碱性玄武岩浆后残留的地幔碎块被岩浆携带上来的。尖晶石二辉橄榄岩平衡温度为1015~1114℃,压力为1.86~1.99GPa。形成深度为60~70km。玻基橄辉岩与碱性橄榄玄武岩的同位素年龄为28~51Ma。  相似文献   
6.
Biomass gasification, which can be categorized as a set of relatively clean processes, is a good option for hydrogen production. The main purpose of the present work was to focus on the use of natural olivine as a bed material to minimize the tar content and enhance the hydrogen yield. The catalytic gasification tests were carried out in a fluidized bed gasifier using steam as the fluidizing medium. Hydrogen yield slightly increased from 51.9 to 53.1 g/kg biomass, as biomass particle size (BP) decreased from 5.0 to 2.0 mm. The yield of tar also decreased from 0.15 to 0.07 g/Nm3 with BP decreasing from 5.0 to 2.0 mm. With an increase in the catalyst-to-biomass ratio (C/B) from 0.2 to 0.8, HY increased from 47.8 to 51.9 g/kg biomass and tar content (TC) decreased from 0.8 to 0.15 g/Nm3. Temperature and steam/biomass ratio (S/B) were also affected the syngas composition and HY, significantly.  相似文献   
7.
Bimetallic Cu/Ni/olivine oxygen carriers (OCs) were prepared using olivine as support material for chemical looping gasification (CLG). The cyclic redox behaviors and oxygen carrying capacity (Ro) of OCs were evaluated by thermo-gravimetric analysis. The effect of Cu/Ni ratio, gasification temperature, steam to biomass ratio (S/B), oxygen carrier to biomass ratio (OC/B) on CLG of cotton stalk has been studied in a fixed bed. The OCs characterized using BET surface area, scanning electron microscopy (SEM), X-ray diffraction (XRD), temperature-programmed reduction (TPR) to investigate the physicochemical property of OCs during CLG. Result shows that the sintering problem of OC was progressively alleviated with the increasing Cu/Ni ratio. The olivine behaves as suitable OC support with oxygen carrying capacity of 1.07%. The redox reactivity of all of the OCs kept well during multiple redox cycles. The Ro of OCs progressively increased with the Cu/Ni ratio. By comparing the product gas concentration, carbon conversion, H2 + CO yield and gas yield over the invested OCs, the Cu9/Ni6/O was found to demonstrate better comprehensive CLG performance due to the synergistic effect of Cu and Ni. The maximum gas yield, H2 + CO yield and carbon conversion with Cu9/Ni6/O can be obtained at the S/B of 0.8 and OC/B of 2. Compared to theoretical value, 65% of lattice oxygen has been supplied by Cu9/Ni6/O during actual CLG process. The OC displayed better reactivity due to basic crystalline phase being preserved well during multiple CLG cycles.  相似文献   
8.
为减少大气中二氧化碳的排放量,人们提出了各种各样的处置方式,其中矿物封存是一种永久、安全且潜力巨大的处置方式。介绍了实验研究矿物封存二氧化碳的原理、流程、原料选择以及反应体系,对比分析3种矿物碳酸盐化反应体系的优缺点以及影响矿物封存二氧化碳的因素,总结出几种封存潜力较大的矿物原料,且进一步分析了压力、温度、PH值、矿物颗粒大小和原料等影响矿物封存的主要因素,并提出最具潜力的封存方式和实验下一步研究的方向和重点。  相似文献   
9.
The Miscanthus X giganteus (MXG) presents many advantages (high yield, perennial crop, easy harvesting…) so it can be considered as a good candidate in terms of renewable energy sources. Several works have been carried out and were devoted to the MXG, especially in the agricultural field, but this study is the first which deals with gasification in order to produce syngas. The catalytic steam gasification of MXG in a fluidised bed reactor into presence of olivine based catalysts was investigated. Three parameters were studied, the temperature (800 °C and 900 °C), the pellets size (6 mm and 8 mm) and the nature of catalyst (olivine and Ni/olivine). Noteworthy is the efficiency shown by the Ni/olivine at 800 °C, which leads to the production of 1.7 m3 kg− 1 daf of gas, containing 50% of H2. Ni/olivine catalyst was characterised by XRD, TPR and SEM-EDX in order to monitor its structural changes during the process. Moreover, a solvent system of tar recovery was tested, which allows to obtain a more representative set of the whole tars. Then, the tars composition was determined by GC/MS. The identification of different compounds shows the presence of different PAHs, in majority naphthalene.  相似文献   
10.
火山矿物对烃源岩生烃演化作用的研究现状   总被引:13,自引:2,他引:11  
在火成岩发育的烃源层中,火山矿物橄榄石的蛇纹石化产生大量的氢气和甲烷,它们参与了烃源岩有机质的生烃演化过程,加大和加速其生烃排量。火成岩在低湿热上蚀变形成的沸石、绿泥石和方解石等矿物对其周围的烃源岩的生烃有显著的催化作用,能够促使烃源岩低熟和早期生烃;其中沸石的催化活性最为显著,绿泥石和碳酸盐在烃源岩中的含量一般较低,且催化活性较小。  相似文献   
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