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Mg-Ni基储氢合金的研究进展与发展趋势   总被引:1,自引:1,他引:0  
系统阐述了近年来Mg-Ni基储氢合金的研究开发概况,指出Mg-Ni基储氢合金具有放电容量高、资源丰富、价格低廉等突出优点,分析了影响Mg-Ni基储氢合金储氢性能的主要因素,总结了近年来采用的行之有效的改进方法,主要有制备非晶/纳米晶、元素替代、添加催化剂等,并对Mg-Ni基储氢合金今后的发展方向进行了探讨与展望,指出Mg-Ni基储氢合金虽然前景可观,但是要实现实际应用仍然存在一些问题需要解决。  相似文献
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在700℃、2h焙烧条件下,用共沉淀法制备可以形成ABO3化合物,对用Ce、Cu部分取代A位La的La1-xA′xNiO3(A′=Ce、Cu)催化剂,随取代量x增加,催化剂愈易被还原。当x≥0.2后,体系中出现掺杂离子的氧化物杂质相,催化剂实际上是ABO3相与氧化物相混合体。对CO氧化反应,x=0.4时其活性最佳,这是ABO3相与氧化物杂质相协同作用的结果。焙烧温度升高,既使催化剂烧结又使催化剂中带有缺陷的晶格完整化,从而使催化剂的活性下降。  相似文献
3.
High-temperature AC magnetic properties for (Fe0.5Co0.5)73.5Cu1Nb3Si13.5B9 alloy annealed at various temperatures have been investigated using an impedance analyzer. Annealing temperature Ta has obvious effects on high-temperature AC magnetic properties of the alloy. The Hopkinson peak appears only in the amorphous alloy when Ta ≤ 703K. As Ta increases above 733K, the real part of the complex initial permeability μi' descends gradually, μi' decreases more slowly with temperature in the high temperature range. The high-temperature (about 750K) AC initial permeability for the alloy annealed at Ta=763K has been found to maintain a stable high value of 950 up toa frequency of~ 1 × 105Hz Partial substitution of Co for Fe in the Fe73.5Cu1Nb3Si13.5B9 alloy leads to an increase of around 110K of the Curie temperature of the amorphous phase, much higher than Ge-containing Finemet alloy.  相似文献
4.
In the paper a model is proposed that is able to explain the superconductor volume/total volume fraction shape vs. the doping concentration for copper oxide-based superconductors with a single Cu-O layer. The results of this model are in good agreement with the experimental determinations. The model is based on a postulate—the necessity for loss of overlap of copper and oxygen orbitals for the appearance of superconductivity, i.e., a distortion of superconducting layers. The distortion is achieved by substituting a kind of ion from the parent compound with another kind of ion that have different charge in comparison with the former. The electrostatic interactions of the doped ions with the lattice lead to superconductivity.  相似文献
5.
关键链上受限资源的优化调度,能有效提高系统运作效率,是关键链项目管理的重要研究方向之一.但现有研究主要针对资源能否更新,较少考虑资源的可替代性.针对此,研究了关键链上可被部分替代的受限资源调度问题,以达到提高资源利用率、降低成本等目的.采用α/β/γ三元组方法,将研究的问题描述为以最小化滞后时间和为目标,具有机器适用限制的并行异速机调度问题,并建立对应的数学模型;运用混合重调度策略和改进粒子群算法进行了算法设计;设计了仿真算例,并通过算法比较表明该方法在求解结果和问题求解规模上显著优于传统PSO、GA算法.  相似文献
6.
It has been argued by some that the substitution of biofuels for gasoline could increase greenhouse gas (GHG) emissions, rather than reduce them. The increase is attributed to the indirect land use change effects of planting new grain and corn crops around the world to replace those progressively being devoted to ethanol production. In this paper, indirect effects are minimised by allowing land to be used for both food and fuel, rather than for one or the other. We present a sugarcane ‘feed+fuel’ biorefinery, which produces bioethanol and yeast biomass, a source of single-cell protein (SCP), that can be used as a high-protein animal feed supplement. The yeast SCP can partially substitute for grass in the feed of cattle grazing on pasture and thereby potentially release land for increased sugarcane production, with minimal land use change effects. Applying the concept conservatively to the Brazilian ethanol and livestock industry our model demonstrates that it would be technically feasible to raise ethanol production threefold from the current level of 27 GL to over 92 GL. The extra ethanol would meet biofuel market mandates in the US without bringing any extra land into agricultural or pastoral use. The analysis demonstrates a viable way to increase biofuel and food production by linking two value chains as called for by industrial ecology studies.  相似文献
7.
Thin films of Mg2−xAlxNi alloys have been prepared by magnetron sputtering, and the effects of partial substitution of Al for Mg on the electrochemical properties of the films were studied. EIS results indicate the rate-limiting process for the thin film hydride electrode is the charge transfer reaction during the process of total discharge. A theoretical model has been derived for the impedance of a thin film hydride electrode based upon the assumption that hydrogen diffusion is neglected in the electrode. The charge-transfer reaction rate at the electrode surface and hydrogen diffusivity in the Mg2−xAlxNi thin film hydride electrodes were observed to initially decrease then increase with increasing Al content. Results from capacitance measurements indicate n-type semiconductor properties for the corrosion layer during the charge–discharge process. Hydrogen atom and OH transfer became more difficult with increasing Al content until x = 0.3, after which a significant drop in the barrier resistance was observed.  相似文献
8.
本文综述了近年来Mg—Ni基贮氢合金元素替代发展状况。元索取代影响Mg—Ni基贮氢合金贮氢量、吸放氢温度等吸放氢性能,改善Mg-Ni合金的电化学容量、活化性能、循环稳定性等电化学性能。对此,提出了合金需要解决的问题。  相似文献
9.
为证明经典变分原理中存在反映的规律为本构关系的变分原理,从非线性弹性动力学的基本方程出发,应用变积方法建立非线性弹性动力学Hamilton原理.再应用对合变换法、Lagrange乘子法和局部代入法,将Hamilton原理变换为本构变分原理.论证了该变分原理反映的规律为本构关系,本研究以非线性材料为例,找到了一个新的材料本构关系的获得途径,为数值建模提供了理论依据.研究结果表明,补充和完善了经典变分原理中对3类基本规律的反映,即:最小势能原理反映的规律为平衡关系、最小余能原理反映的规律为连续关系和本构变分原理反映的规律为本构关系.  相似文献
10.
A series of LaNi1−xTixO3 perovskite catalysts varying titanium (x = 0.0, 0.2, 0.4, 0.5, 0.6 and 1.0) are synthesized and investigated using BET, XRD, TPR, TEM, FT-IR and XPS. The catalysts were evaluated for oxy-carbon dioxide reforming of methane at 800 °C under atmospheric pressure maintaining CO2/CH4/O2 ratio 0.8/1.0/0.2. LaNi0.5Ti0.5O3 is showing typical stability with gradual H2 consumption in TPR. The stability of these catalysts is supported by O 1s binding energies wherein it is clearly evident that incorporation of Ti stabilized LaNiO3 generating suitable catalysts in the range of x = 0.4–0.6 with high performance.  相似文献
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