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121.
The phase diagram of the ternary system Cr-Mo-O in air was established from the results of thermal analysis of mixtures with different initial CrO3 to MoO3 ratios. It was found that MoO3 did not take any chromium oxide into solid solution. The presence of Cr2O3 destabilized MoO3 causing it to decompose to MoO2 in the temperature range 723-958 K depending on the initial Cr/Mo ratio. The decomposition of pure MoO3 MoO2 did not occur in air at any temperature. However, this decomposition took place through the formation of the compound Cr2O3·3MoO3(ss) and its decomposition to Cr2O3·3MoO2(ss). The latter compound has never been reported before and the X-ray data for this compound are given. The previously reported catalytic activity of Cr2O3·3MoO3(ss), at high temperatures, is presumably due to its reduction to Cr2O3·3MoO2(ss). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
122.
在滴汞电极上研究了硝基苯、对硝基甲苯、间二硝基苯及2,4-二硝基氯苯的电化学行为,并用量子理论对四种硝基苯化合物的反应活性进行了预测,理论与试验结果基本一致,据此提出了预测分子的电化学活性的方法。  相似文献   
123.
The interaction of native and derivatized transferrin with lecithin, cholesterol and their mixtures was studied using monomolecular layers of phospholipids. Moreover, the thermodynamic parameters corresponding to these interactions: the mixing excess free energy, interaction energy, and interaction parameter were also calculated.The ability of these two proteins to insert into monolayers was studied working at constant area.The formation of aggregates or secondary structures in solution was determined by the fluorescence and polarization values of ANS (anilinonaphthalene sulfonate), measured at different protein/ANS relationships.Abbreviations TF Transferrin - DTF derivatized transferrin - PC lecithin - CHOL cholesterol - CER ceramides - ANS anilinonaphthalene sulfonate - TNBS trinitro benzenesulfonate method  相似文献   
124.
Sangeun Cho  Chan Kang 《Electroanalysis》2007,19(22):2315-2320
A nonenzymatic glucose sensor with good selectivity for the ascorbic acid oxidation is presented. After the gold polycrystalline electrode was subjected to amalgamation treatment, two advantageous effects were observed. One is the enhancement of the surface roughness and the other is an increase in the catalytic current in the glucose oxidation. Besides the known first effect, the latter provided another advantageous effect in a fabrication of nonenzymatic glucose sensor. Using a gold electrode subjected to amalgamation treatment for 60 s, two calibration curves for glucose oxidation at two different potentials of ?0.1 V and 0.25 V were obtained and compared. At the potential of ?0.1 V, at which no ascorbic acid was oxidized and no interference effect was observed, a current sensitivity of 16 μA cm?2 mM?1 from zero to 10 mM glucose concentration range was obtained. At the other potential of 0.25 V, at which ascorbic acid was easily oxidized, a satisfactory calibration curve with negligible ascorbic acid interference was also obtained together with a more enhanced current sensitivity of 32 μA cm?2 mM?1.  相似文献   
125.
在二氧化钛载体中通过掺杂Ru,Mn,Ce制备了一系列用于催化湿式氧化的催化剂,利用XRD,TEM,BET等手段对催化剂进行了表征.在反应温度T=210~270℃,氧分压Po2=2.1MPa条件下,在间歇式高压反应釜中对丁二酸进行了降解实验.催化剂在反应中有很高的催化活性.催化剂在30min内对丁二酸降解的COD去除率为54.4~98.3%.Ru及Mn,Ce的氧化物对催化活性都有促进作用.建立了丁二酸催化湿式氧化的一级分段动力学模型.基于COD的一段及二段反应的活化能分别为43.74kJ/mol和54.28kJ/mol.  相似文献   
126.
The toxicity of steroids 1-11 for colorado beetle (Leptinotarsa decemlineata Say.) larvae was studied by contact-intestinal treatment. Active insect-growth regulators were found among the studied compounds.  相似文献   
127.
128.
N-salicylidene-benzylamineato M(Ⅱ) complexes (ZnL2, CuL2 and CdL2) were synthesized, characterized and valued for antimicrobial activities against bacterial strands using the agar diffusion method. The crystal of ZnL2 was determined by X-ray diffraction. It crystallizes in the Monoclinic system, space group C2/c with a=2.269 1(3), b=0.918 2(1), c=1.239 5(2) nm, β=117.89(2), Z=4, R1=0.049 4, wR2=0.138 2. The complexes were found to be active against Staphylococcus aureus and Eschierichia Coli. CCDC: 249474.  相似文献   
129.
以三乙胺为缚酸剂,用芳氧乙酸同ω-溴代-ω-(1H-1,2,4-三唑-1-基)频哪酮反应,合成了一系列三唑类新化合物,探讨了化合物的合成方法。通过IR ̄1HNMR、MS分析及元素分析确定了化合物的结构,生物活性测定结果表明,部分化合物具有良好的除草活性,同时表现出一定程度的植物生长调节活性及杀菌活性.  相似文献   
130.
The system H2O-B2O3-Na2O has been studied experimentally at 277 and 317°C. The activities of water and boric acid have been determined at mole ratios Na/B from 0 to 1.5, and total dissolved solids 3 to 80 weight percent. The activity of boric acid has been fitted to within experimental error using a speciation model with eight complex species. This model is consistent with the model previously published by Mesmer et al. The electrolyte properties of the liquid are modeled using the Pitzer-Simonson model of very concentrated electrolyte solutions. The calculated values of water activity agree with experiment, and the activity of NaOH and pOH have also been calculated. The potassium borate system also was briefly studied at 317°C, and is adequately described by a model with five complex species. The potassium borate liquid is more alkaline at K/B= 1 than a sodium borate liquid at the same mole ratio, but pOH in the two systems is the same at lower mole ratios.  相似文献   
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