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Microwave direct synthesis and thermoelectric properties of Mg2Si by solid-state reaction ZHOU Shu-cai1, 2, BAI Chen-guang1 1. College of Material and Science Engineering, Chongqing..., which was used for the production of activated Mg and Si particles. It mainly consisted of a microwave oven and a heat preservation system. Fig. 1 Schematic diagrams of microwave system setup......
(a) and annealing for 12 h (b), can be classified into three regions according to their morphology, as shown in Figure 2, and elemental composition, as exemplified in Figure 3. Bulky cubic-like particles... are subjected to temperatures beyond their melting points for up to 2 h in the microwave furnace, the single phase with homogeneous morphology is not yet obtained. The morphology can be more homogeneous......
(NO3)2·6H2O),硝酸铁(Fe(NO3)3·9H2O),硝酸钴(Co(NO3)2·6H2O),十六烷基三甲基溴化铵(CTAB),无水乙醇和去离子水等,以上原料均为分析纯.Zn1-xCoxFe2O4样品通过水热法制备,制备过程如下:根据Zn1-xCoxFe2O4(x=0,0.2,0.4,0.6)的化学量配比,按金属阳离子n(Co):n(Zn):n(Fe)= x:(1-x):2的摩尔比配制称量原料,分别称取Zn(NO3)2·6H2O,Fe(NO3)3·9H2O和Co(NO3)2·6H2O完全溶于60 mL的蒸馏水中,得到混合金属盐溶液,并将其置于磁力搅拌器上进行充分搅拌.待溶液完全溶解后形成均匀稳定的混合溶液,称取一定量的表面活性剂CTAB缓慢加入到上述溶液中,继续搅拌至完全混合均匀.然后将所得混合溶液转移至100 mL带聚四氟乙烯内衬的反应釜中,填充度为80%.最后封闭反应釜并将其放......
at -0.95, -1.00 and -1.05 V in solution composed of 0.05 mol/L CoSO4·5H2O, 0.20 mol/L Na2SO4and 0.05 mol/L C6H5O7Na3·2H2O Fig. 8 Speciation curves for complexes formed in Co(II)-citrate system at 1:2 molar... [J]. Electrochimica Acta, 2007, 53(2): 934-943. [3] XU X, AZNGARI G. Electrodeposition of Co-P films from alkaline electrolytes [J]. Journal of the Electrochemical Society, 2007, 155(12): 742-749. [4......
and the rock specimens will be in early phase of elastic stage with larger σ2 and the number of AE events decreases;3) The failure mode changes under high σ2. 3.4 Infrared radiation properties Through...) and the infrared radiation characterization. The test results show that the failure modes of the granite and red sandstone specimens are changed from shear to slabbing with the increase of σ2. The AE......
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="ChDivSummary">Using high aluminum refractory material as substrate at 1 400 ℃, we studied the connections between several oxides such as Fe 2 O 3, MnO 2, CuO, and the formation of defects such as coating crack... to the substrate. The valent changes of Fe 2 O 3 and MnO 2 during the heating process cause the volatilization of the oxides or the pulverization of the coatings, resulting in the coating fades away easily......
radiation (λ=0.154 06 nm). The fracture surface morphology of the ceramics was studied using a JSM-5610LV scanning electron microscope (SEM). The microwave dielectric properties such as dielectric... Opinion in Solid State Materials Science,1996,1:715-731 [2] UBIC R, REANEY I M, LEE W E. Microwave dielectric solid-solution phase in system BaO-Ln2O3-TiO2[J]. International Materials Reviews, 1998......
2,7-双(5-羧基-1,3,4-三氮唑偶氮)-H酸和过氧化氢催化动力学光度法测定痕量铜(Ⅱ)的研究葛昌华1,潘富友1,梁华定1,林彩飞1(1.浙江省台州市台州学院医药化工学院)摘 要:研究了铜(Ⅱ)催化H2O2氧化2,7-双(5-羧基-1,3,4-三氮唑偶氮)-H酸(BCTZAHA)褪色反应及其动力学条件,并基于褪色反应程度与铜(Ⅱ)量在一定范围内呈线性关系,建立了测定痕量铜(Ⅱ)的催化动力学光度法.在pH 10.0的NH3·H2O-NH4Cl缓冲溶液介质中,褪色体系的最大吸收波长为540 nm,铜(Ⅱ)质量......
3 500.81和3 380.02 cm-1处,的特征吸收峰位于1 548.20,1 348.26和836.15 cm-1处,没有出现Co3O4中Co-O键的吸收峰,表明水热处理后的前驱物为碱式碳酸钴.Co2(OH)2CO3前驱物于450 ℃煅烧3 h的产物在660.81和562.47 cm-1处出现Co3O4中Co-O键的伸缩振动吸收峰,表明此时产物为Co3O4. 图2(c)所示为CoC2O4...文章编号:1004-0609(2011)02-0442-08 前驱体对四氧化三钴形貌的影响与表征 杨幼平,张平民,刘人生,黄可龙 (中南大学 化学与化工学院,长沙 410083) 摘 要:以Co(CH3COO)2·4H2O为钴源,聚乙二醇(PEG)20 000为表面活性剂,在水-正丁醇溶剂体系中,分别以氢氧化钾,碳酸铵和草酸为沉淀剂,采用沉淀法制备氢氧化钴,碱式碳酸钴和草酸钴......