Dawson结构一取代杂多配合物的氧化还原性质的研究

采用电化学方法研究一取代K8[P2 W1 7TiO62 ]· 5H2 O ,K8[P2 W1 7ZrO62 ]·7H2 O ,K8[P2 W1 7(TiO2 )O61 ]· 9H2 O和K8[P2 W1 7(ZrO2 )O61 ]· 4H2 O的氧化还原性质 .实验结果表明 :过氧型杂多配合物的氧化性大于非过氧型杂多配合物的氧化 .Ti取代的杂多配合物的氧化性大于Zr取代杂多配合物的氧化性 .     

Mo—Ce／Sio2催化剂上甲醇氧化制甲醛的动力学与机理

用玻璃外循环无梯度反应器研究了Mo-Ce/SiO_2催化剂的甲醇氧化制甲醛的动力学。吡啶吸附的红外光谱鉴别出催化剂Lewis酸的存在。红外光谱证实甲醇在催化剂上发生化学吸附。用脉冲色谱法测定了甲醇及甲醛的吸附热。随着甲醛分压的增加,甲醇氧化制甲醛的速度随之减小。进行了催化剂被甲醇还原及还原催化剂用O_2再氧化的脉冲实验。甲醇氧化的动力学服从甲醇及甲醛吸附的Redox机理方程。     

强酸性条件下KMnO_4与H_2O_2反应体系的动力学研究

文献[1]发现在强酸性条件下,KMnO_4与H_2O_2反应体系中,KMnO_4的褪色速度随H_2O_2初始浓度的增高而变慢.本文在综合考察体系中各类复杂反应的基础上,从理论上对这一现象进一步加以研究,拟合求得了由褪色速度表征的对应动力学关联方程,并对结果加以讨论.     

杂多钨酸盐K_n[MW_(11)O_(39)Ni(H_2O)]·xH_2O的氧化还原性质研究

通过极谱和循环伏安法,结合紫外光谱和X射线光电子能谱研究了过渡元素K（?）〔MW_(11)O_(39)Ni(H_2O)〕·xH_2O(M=Si、Ti、Ga、Zr)在溶液中的氧化还原性质,提出了它们的还原机理,杂多阴离子的极谱半波电位顺序为Zr>Ti>Ga>Si,发现杂多阴离子的E_(1/2)与M元素的电负性有线性关系.     

Fe(CN)_6~(3-/4-)在铂电极上氧化还原过程的表面拉曼光谱研究(英文)

本文运用共聚焦显微拉曼仪结合特殊的电极表面粗糙方法首次获得了Fe(CN)_6~(3-/4-)在铂电极表面氧化还原过程的拉曼光谱图。研究结果表明Fe(CN)_6~(3-)在电极表面的吸附能力比Fe(CN)~(4-)强,它们都是通过CN上的N原子和电极表面成键而发生化学吸附的。     

BPO—DMA引发氯丁橡胶接枝共聚的研究

研究了温度、时间、BPO-DMA用量配比对MMA接枝CR的影响,得出了能体现该氧化还原引发聚合特征的反应条件。当[BPO]=[DMA]=0.01 mol/1,40℃～55℃反应3 h接枝率可达一峰值(～14％)。XPS和SEM分析结果,证明产物为一接枝共聚物;且接枝率为10～14％时粘接强度迅速增加,接枝聚合的活性中心在CR 双键的α-H位置。     

二过碘酸合银(Ⅲ)——乙酰丙酮体系引发丙烯腈聚合反应的研究

本文用水相沉淀聚合法研完了二过碘酸合银(Ⅲ)络离子[Ag(Ⅲ)]—已酰丙酮氧化还原体系在碱性介质中引发丙烯腈的聚合反应。测定了各种反应条件对聚合反应速率(Rp)和聚合物分子量的影响。探讨了引发反应机理。     

Redox condition during Ediacaran–Cambrian transition in the Lower Yangtze deep water basin,South China: constraints from iron speciation and δ~(13) Corg in the Diben section,Zhejiang

Cherts of the Piyuancun Formation and black mudstones of the Hetang Formation in Diben Town, Kaihua County, Zhejiang were deposited in a deep water basin of the Lower Yangtze area during the Ediacaran–Cambrian transition(E–C transition), offering an opportunity to reconstruct the ancient redox condition of the deep water basin. Total 53 samples were collected and analyzed for iron speciation, including pyrite iron(FePy), carbonate associated iron(FeCarb), iron oxide and hydroxide(FeOx),magnetite iron(FeMag) and total iron(FeT) as well as d13 Corgto gain a deeper understanding of specific redox condition during the period. The results show that(1) most samples have pyrite concentration \1 %, with the FePy/FeHR ratio ranging from \0.01 to 0.81(mostly \0.5), and the FeHR/FeT ratio between 0.39 and 0.93(mostly [0.5).(2) The E–C boundary in the Diben section occurred at the maximum negative excursion of organic carbon isotope within the Piyuancun Formation, which can be correlated with other sections by using d13 Corg. We thus concluded that the relatively high content of highly reactive iron and low content of pyrite iron in the Diben section indicate a minor occurrence of H2 S and a predominance of anoxic and ferruginous environment, which is similar to other reported sections such as the Longbizui and Yanwutan sections, western Hunan. In addition, oxygen concentration in sea water showed an increasing trend in the interval corresponding to the bottom and upper layer of the Hetang Formation as indicated by the FeHR/FeT ratio, which decreased from 0.7 to 0.38, however, it was not great enough to oxidize the whole deep water. Therefore, during the E–C transition deep water basin in South China was most likely an anoxic and ferruginous enrironment, which prevented metazoon from the evolution in the deep water basin. Our work offers an important reference to better understanding of the spatiotemporal occurrence and dynamic processes of the ‘‘Cambrian Explosion'.     

L-抗坏血酸紫外分光光度法检测微量过氧化氢

建立了L-抗坏血酸（L—Aseorbieacid）紫外分光光度法测定微量过氧化氢的新方法．在pH=5．7的磷酸缓冲溶液介质中,选择273nm作为测定波长,过氧化氢的摩尔浓度在0～0．1mmol／L范围内服从比尔定律．回归方程为：y=0．0049＋4．44612x（mmol／L）,检出限为0．401μmol／L．该法用于溶液中、生物组织等样品中微量过氧化氢浓度的测定,快速简便．     

碱性介质中二过碘酸合铜（Ⅲ）配离子氧化氨基乙酸的反应动力学

本文用分光光度法研究了碱性介质中二过碘酸合铜（Ⅲ）配离子氧化氨基乙酸的反应动力学。实验结果表明反应对Ｃｕ（Ⅲ）是准一级。表观速率常数ｋｏｂｓ随着氨基乙酸浓度的增加而增大，随着〔ＯＨ－〕的增大而增大，但随着〔ＩＯ－４〕的增大反而减小；且发现１／ｋｏｂｓ对〔氨基乙酸〕和１／ｋｏｂｓ对〔ＩＯ－４〕有线性关系。据此提出了一种含有前期平衡的反应机理，推出了一个能够解释全部实验事实的速率方程式，求得了速控步骤的速率常数ｋ，并给出了相应的活化参数。