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21.
膜催化反应器的分析与模拟 总被引:2,自引:1,他引:2
分析了膜反应器的出现、发展和最新研究。论述了几种膜反应器中气体的传递机理,定量分析了膜反应器中控制传递与反应的模型方程式以及计算机模拟和实验研究结果。最后评价了两类膜反应器的操作特性,以⊿n<0、⊿n=0和⊿n>0三类不同的催化反应作为模型反应与传统的PFR 和 MFR 的操作特性作了对比。 相似文献
22.
若干无机盐对聚丙烯酰胺溶液粘度的影响 总被引:1,自引:0,他引:1
探讨了无机盐溶液中阴阳离子对聚丙烯酰胺(PAM)溶液粘度的影响,确定了影响PAM溶液粘度的主要因素是二价阳离子(如ca2 及Mg2 离子)。 相似文献
23.
Single crystals of gadolinium–sodium polyphosphate NaGd(PO3)4 were grown for the first time using a flux method and characterized by X-ray diffraction. This phosphate crystallizes in a monoclinic system with P21/n space group and with the following unit-cell dimensions: a = 9.767(3) Å, b = 13.017(1) Å, c = 7.160(2) Å, β = 90.564(5)°, V = 910.3(4) Å3 and Z = 4. The crystal structure was solved from 3451 X-ray independent reflections with final R(F2) = 0.0219 and Rw(F2) = 0.056 refined with 164 parameters (). The atomic arrangement can be described as a long chain polyphosphate organization. Two infinite (PO3)∝ chains with a period of eight tetrahedra run along the [0 1 1] direction. The structure of NaGd(PO3)4 consists of GdO8 polyhedra sharing oxygen atoms with phosphoric group PO4. Each Na+ ion is bonded to eight oxygen atoms. 相似文献
24.
Xiao-Yan Chang Xin-Hai Li Long Zhang Hua-Jun Guo Wen-Jie Peng 《Materials Research Bulletin》2005,40(9):1513-1520
Pure and carbon-containing olivine LiMn0.7Fe0.3O4 were synthesized at 600 °C by the method of solid-state reaction. Structure, surface morphology and charge/discharge performance of LiMn0.7Fe0.3O4 were characterized by X-ray diffraction, scanning electron microscopy, and electrochemical measurement, respectively. The prepared materials with and without carbon both show the single olivine structure. The morphologies of primary particles are greatly affected by the addition of carbon. Large particles (500-1000 nm) and densely sintered blocks were observed in pure LiMn0.7Fe0.3PO4, which made the insertion and extraction of lithium ions difficult. Battery made from this sample can not charge and discharge effectively. The carbon-containing LiMn0.7Fe0.3PO4 has a small particle size (100-200 nm) and a regular appearance. This material demonstrates high reversible capacity of about 120 mAh g−1, perfect cycling performance, and excellent rate capability. It is obvious that the addition of carbon plays an important role in restricting the particle size of the material, which helps to prepare LiMn0.7Fe0.3PO4 with excellent electrochemical performance. The electrochemical reaction resistance is much lower in the partly discharged state than in the fully charged or fully discharged state by the measurement of ac impedance for carbon-containing LiMn0.7Fe0.3PO4. It is indicated that the mixed-valence of Fe3+/Fe2+ or Mn3+/Mn2+ is beneficial to the transfer of electron which happens between the interface. 相似文献
25.
M.V.V.M. Satya Kishore 《Materials Research Bulletin》2005,40(10):1705-1712
LiCo1−xMxPO4 (M = Mg2+, Mn2+ and Ni2+; 0 ≤ x ≤ 0.2) compounds have been synthesized by solid-state reaction method and studied as cathode materials for secondary lithium batteries. LiCoPO4 exhibits a discharge plateau at ∼4.7 V with an initial discharge capacity of 125 mAh/g and on cycling capacity falls. Substitution of Co2+ with Mg2+/Mn2+/Ni2+ in LiCoPO4 has an influence on the initial discharge capacity and on cycling behaviour. The capacity retention of LiCoPO4 is improved by manganese substitution. Among the manganese substituted phases, LiCo0.95Mn0.05PO4 shows good reversible capacity of ∼50 mAh/g. 相似文献
26.
豆类低聚糖的开发应用 总被引:3,自引:0,他引:3
本文对有关豆类低聚糖的分布,生理功能,分离纯化途径及食品加工性能等方面进行了分析和论述,认为豆类低聚糖是一类有利于人体健康的新型低聚糖,值得开发利用。 相似文献
27.
塔里木,准噶尔盆地石油生成与演化 总被引:7,自引:7,他引:7
以塔里木、准噶尔盆地干酪根、沥青的Pb、Sr、Nd同位素分析资料,回答了地质学家必须回答的四个问题:①石油是由舒什么生成的;②石油是如何生成的;③石油是地何时生成的;④石油是何时运移的。根据Pb、Sr、Nd同位素所揭示的信息指出,塔里木、准噶尔盆地的石油虽然是在不同构造背景下生成的,生油模式、生油年龄和运移年龄也不相同,但都是由费托合成反应无机生成的。作者指出,地救化学急变对油气田分布的控制作用十 相似文献
28.
CeF3 nanoparticles 5-10 nm in size were prepared using the polyol method. CeCl3 and HF were heated up in ethylene glycol. At a temperature of 180 °C crystalline CeF3 nanoparticles were formed. The material was washed with ethanol, centrifugated and dried. The particles were characterized by EDX, XRD and TEM. 相似文献
29.
Shigeo Asai Kunihito Koumoto Yushu Matsushita Eiji Yashima Masahiko Morinaga Kunihiko Takeda 《Science and Technology of Advanced Materials》2013,14(5):421-433
The center of excellence (COE) titled ‘The Creation of Nature-Guided Materials Processing’ has been established in Nagoya University as the 21st Century COE Program supported by Ministry of Education, Culture, Sports, Science and Technology. In the Nature COE, various activities on the education and research are being performed through learning the laws of nature, namely, methods of attaining ‘appearance of the maximum function under the minimum substance and energy consumption’, which the nature and living organisms have acquired through their evolution in long period. Together with such educational programs for PhD students as research incentive, oversea training, and external evaluation programs, an ‘Open-Cluster Program’ was originated for promoting researches proposed by research groups consisting of young researchers in and out of the university and also for fostering them.The researches are being advanced on materials used for living bodies, mimicking structures which nature or living bodies are forming, and producing materials by mimicking processes to form the structures observed in the nature or the living bodies. In this COE, these researches are conducted by four groups to extend the processes observed in the natural world to a new type of processing, that is, thoroughly examined and rationalized by plunging a scalpel of engineering and to establish a new academic field of materials science and engineering. 相似文献
30.
本文综述了无机分离膜在应用领域的研究情况,着重介绍了无机分离膜在气体分离、膜反应器、生物反应器和血浆成分分离等方面的应用,讨论了无机膜自身的缺陷和今后有待研究解决的课题. 相似文献