A Study on Thermal Decomposition of K_3[Fe(CN)_6] and KFe[Fe(CN)_6] in Helium

K3 [Fe(CN)6] and KFe[Fe(CN)6] are classical coordination compounds. However, the mechanism of decomposition reactions has not been well expounded. The gas products of thermal decomposition were examined by gas chroma tography (GC) , and the structure of the solid products by Mossbauer spectroscopy(MS) and X-ray diffraction(XRD). The findings are explained in terms of the theory of coordination chemistry and a decomposition mechanism is proposed in this study. On the basis of various experimental results, the first stage of the decomposition of K3[Fe(CN)6] in He was found to be the evolution of(CN)2 resulting in the reduction of Fe(Ⅲ)12K3 [Fe(CN)6]→9K4[Fe(CN)6] + Fe2 [Fe(CN)6] + 6 ( CN )For KFe [Fe(CN) 6 ], the first stage of decomposition man be represented as6KFe[Fe(CN)6]→3K2Fe[Fe(CN)6] + 2Fe2[Fe(CN)6 + 3(CN)2At higher temperatures, the decomposition of both K3[Fe(CN)6) andKFe[Fe(CN)6] to form KCN and Fe2C was accomplished by the release of(CN)2 and N2.     

Some triplet energy-transfer reactions initiated by photoexcitation of triplet excited state of dibenz[a,h]anthracene to the higher triplet excited states

Some triplet energy-transfer reactions initiated by photoexcitation of the triplet excited state of dibenz[a,h]anthracene to higher triplet excited states (DBA(T_n)) were observed in the presence of the triplet energy quenchers (Q) such as naphthalene, biphenyl, p-dichlorobenzene, and o-dicyanobenzene. In the case of carbon tetrachloride (CCl₄) as Q, DBA(T_n)-sensitized decomposition of CCl₄ occurred.     

Tetrachlorosilane Consumption in Radio Frequency Glow Discharge

Time-resolved mass spectrometry was used for analysis of the plasma reactions in radio frequency (RF) SiCl ₄ and SiCl ₄ –O ₂ discharges as functions of starting partial pressure and electrical power. Molecular concentrations of the reactants and products from SiCl ₄ alone and with O ₂ were obtained from the mass spectra and used for plotting the kinetic curves. The SiCl ₄ and O ₂ consumption rates were calculated from the kinetic curves and compared with results of theoretical simulation of the reaction. Direct electron impact decomposition was found to be the main pathway for pure SiCl ₄ conversion. On the contrary, the consumption of SiCl ₄ in the SiCl ₄ +O ₂ mixtures was largely chemical. The experimental macrokinetics are in agreement with a model in which oxidation is caused by the atomic oxygen.     

固相热分解反应最可几机制的判断

固相热分解反应最可几机制的判断高永煜，邹文樵，冯仰婕（华东理工大学化学系上海２００２３７）关键词热分解，动力学方程，反应机制固相热分解反应机制的判断，是热分析动力学中令人感兴趣的领域。常用的方法是从含机制函数的非等温积分动力学方程出发，分别用Ｓｅｓｔ...     

戊二酸钛（Ⅲ）与氮化钛的制备

戊二酸钛（Ⅲ）与氮化钛的制备陈吉书，吕真国，徐其亨（曲靖师专化学系曲靖）（曲靖地区环境监测站曲靖）（云南大学化学系昆明６５００９１）关键词戊二酸钛，氮化钛，热分解氮化钛具有硬度大、熔点高、耐磨、耐腐蚀、导电性好、美观（金黄色）等优点，具有重要的工业用...     

Reaction and mass transfer effects in a catalytic monolith reactor

Zeolite-based monoliths (Cu/ZSM-5 on cordierite) are prepared and used to catalyze direct decomposition of nitrogen monoxide. Two-dimensional heterogeneous model is applied to describe the behavior of the monolith reactor, with the emphasis on the features introduced due to coupling of flow, mass transfer and chemical reaction. The proposed model has been verified by comparing computer simulation data with laboratory experimental data. It is shown that both inter- and intraphase diffusion limitations have to be considered when modeling complex reactor configuration, such as monolith reactors, especially when monolith with thicker catalytic layer are used at higher temperatures.     

脉冲电晕环境中13X分子筛对NO分解作用的研究

在常温、常压下，利用脉冲电晕放电产生冷等离子体，使一氧化氮发生分解，直接生成氮气和氧气，用四极杆质谱仪在线测量反应过程中反应物和生成物的变化。在自行研制的实验台上，考察了13X分子筛在不同的脉冲电晕放电条件下，表现出来的不同特性及其对反应转化率的影响。在30 ℃～430 ℃、流量375 mL/min～1 333 mL/min，分析了该反应过程中13X分子筛对转化率的促进作用。在同一脉冲放电条件下，控制13X分子筛的温度为200 ℃，转化率从30 ℃时的1.2%上升到19.7%；转化率最高可以达到35.9%。并对反应过程中13X分子筛的吸附特性做了初步探讨。     

Phase evolution of a barium tin 1,2-ethanediolato complex to barium stannate during thermal decomposition

The thermal behaviour of [Ba(C₂H₆O₂)₄][Sn(C₂H₄O₂)₃] used as a BaSnO₃ precursor, and its phase evolution during thermal decomposition are described. The initially formed transient barium tin oxycarbonate phase disintegrates into BaCO₃ and SnO₂, reacting subsequently to BaSnO₃. The existence of the intermediate oxycarbonate phase is evidenced by Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD) and electron energy loss spectroscopy (EELS (ELNES)) investigations.     

锂离子二次电池电解质材料LiPF6的制备及表征

0引言 液态锂离子电池自1990年开发成功以来,由于具有比能量高、工作电压高、应用温度范围宽、自放电率低、循环寿命长、无污染、安全性能好等许多独特的优势[1],所以其发展前景十分广阔.目前液态锂离子二次电池中开发使用的无机阴离子导电盐主要有LiClO4、LiPF6、LiAsF6等,但LiClO4为强氧化剂,使用不安全而不宜用于电池,LiAsF6虽然性能颇佳,但有毒且价格较贵,故也不宜广泛使用.LiPF6被认为是目前较合适的电解质[1],但其制备困难,价格较贵,且目前报道的合成方法也多是以HF为介质[2～5].本文作者以PF5和LiF为原料在CH3CN溶剂中简单有效地合成了高纯LiPF6,并通过在手套箱中制样的方法对目标产物进行了红外、热重和X射线衍射分析,给出了LiPF6的红外光谱图、热重分析数据和X射线衍射图.     

铁(III)卟啉催化β-胡萝卜素分解动力学研究

使用BeckmannDU-8B紫外可见分光光度计研究了以氯合四－间三甲苯基卟啉铁（Ⅲ）（FeTMPCl）为催化剂，间氯过氧化苯甲酸（mCPBA）为氧化剂，咪唑（I_m）、2－甲基咪唑（MeI_m）、2－乙基－4－甲基咪唑（EMI_m）为轴向配体，催化β-胡萝卜素（β－cte）氧化分解为维生素A的动力学规律，提出了反应机理，研究了温度、催化剂浓度、氧化剂浓度及轴向配体对反应速率的影响，应用Gauss－Newton－Marquardt方法求得各基元反应的有关动力学参数．