铁酸镁系列超微粒子催化剂的氧化脱氢反应行为:乙苯和环己烷的氧化脱氢反应

采用四种不同的方法制备了系列铁酸镁超微粒子催化剂，考察了其对乙苯和环已烷的氧化脱氢反应性能，结果表明，（Ｄ）样品具有最佳的乙苯氧化脱氢反应活性：４００℃，Ｏ２／Ｃ６Ｈ５Ｃ２Ｈ５（ｍｏｌ）＝３．０时，乙苯转化率为５０％，苯乙烯选择性为８０％，苯乙烯单收达４０％，催化剂对乙苯氧化脱氢反应的活性随样品的粒径变小而提高；对环已烷氧化脱氢反应则恰好相反，即活性随粒径变小而降低，这种差别归因于反应物分子结构与     

铁酸镁系列超微粒子催化剂的氧化脱氢反应行为乙苯和环己烷的氧化脱氢反应

采用四种不同的方法制备了系列铁酸铁超微粒子催化剂，考察了其对乙苯和环己烷的氧化脱氢反应性能．结果表明，（Ｄ）样品具有最佳的乙苯氧化脱氢反应活性：４００℃，Ｏ２／Ｃ６Ｈ５Ｃ２Ｈ５（ｍｏｌ）＝３．０时，乙苯转化率为５０％，苯乙烯选择性为８０％，苯乙烯单收达４０％．催化剂对乙苯氧化脱氢反应的活性随样品的粒径变小而提高，对环己烷氧化脱氢反应则恰好相反，即活性随粒径变小而降低．这种差别归因于反应物分子结构与催化剂表面原子配位结构的匹配作用．ＥＳＲ结果对比表明，粒径小的粒子的原子配位结构对称性较低．     

CoFe2O4纳米微粒的制备及其催化性能

采用溶胶-凝胶法制备了铁酸钴纳米微粒催化剂，运用XRD、IR、TPR以及BET比表面测试等手段对所制备的样品进行了表征。研究了铁酸钴的结构和氧化还原性质，考察了铁酸钴对二氧化碳选择性氧化乙苯制苯乙烯的催化性能。结果表明：制备的铁酸钴微粒的比表面积为36.3m^2/g，晶粒大小约为30nm。在由二氧化碳选择性氧化乙苯制苯乙烯的反应中表现出较好的催化活性。     

铁酸镁在2，3，6－三甲基苯酚羟基化反应中的催化性能

 采用共沉淀法与柠檬酸法合成了铁酸镁，并用X射线衍射和红外光谱等对不同样品进行了表征．以三甲基苯酚为原料，以铁酸镁为催化剂，以双氧水为氧化剂，实现了一步羟化为三甲基对苯二酚（维生素E重要中间体）的目的．详细考察了催化剂、温度、溶剂和双氧水等因素对该反应体系的影响．结果表明，铁酸镁对该反应体系具有很好的催化效果，较常用的羟化催化剂TS－1分子筛等的催化性能好得多．该过程可以进一步研究发展成为一个环境友好催化过程．     

纳米铁酸铋及其改性物的环境催化性能

铁酸铋（BiFeO₃）是一种典型的钙钛矿型氧化物,具有一定的可见光催化和多相类芬顿催化性能。在可见光照射且存在过氧化氢的情况下,BiFeO₃可活化过氧化氢并产生强氧化性物种,这些物种会攻击污染物分子从而使其降解。但BiFeO₃量子效率不高,光生电子和空穴容易复合;其活化过氧化氢的能力也有待提高。本文综述了近二十年来铁酸铋及其改性物作为可见光催化剂及多相类芬顿催化剂的研究进展,重点介绍了在制备过程中对其形貌的调控、贵金属沉积、离子掺杂、半导体复合、或负载于其他材料表面等改善其环境催化性能方法与效果,改性后发现BiFeO₃的可见光催化和多相类芬顿催化性能均得到提升。最后,对铁酸铋复合催化剂未来的发展方向进行了展望。     

氧化镍中非化学计量氧在乙烷氧化脱氢中的作用

以纯ＮｉＯ为模型催化剂考察了乙烷氧化脱氢（ＯＤＨＥ）性能，发现非化学计量氧的存在与反应的活性及选择性密切相关．ＴＧＡ研究结果表明，５００℃制备的样品具有ｘ≈６％的非化学计量氧．Ｈ２ＴＰＲ结果表明，非化学计量氧与晶格氧的可还原性明显不同；Ｏ２ＴＰＤＭＳ又把非化学计量氧区分为两个氧物种，Ｏ－２和Ｏ－（或Ｏ２－２）．脉冲试验结果表明，非化学计量氧对ＯＤＨＥ制乙烯是选择性反应的活性氧物种，晶格氧是完全氧化反应的活性氧物种．一旦催化剂中非化学计量氧耗尽并动用晶格氧时，催化剂便有Ｎｉ０生成，表现出自催化性能，使反应活性迅速提高，但产物均为ＣＯ２，ＣＯ，ＣＨ４等完全燃烧或裂解产物．为保持有较高的乙烯收率，反应处于稳态时Ｎｉ必须处于高价态．电导测定结果表明，优良的ＯＤＨＥ催化剂应有Ｐ型半导性．     

活性氧缺位铁酸铜的制备及其在热化学分解水制氢中的应用

热化学循环分解水制氢是近年来国际上核能制氢计划的研究热点课题,除美国通用原子能公司（GA）发明的碘硫（IS）循环和东京大学发明的UT-3循环外,作为最简单的热化学循环制氢体系,氧化物体系热化学分解水制氢近年来受到了国际上的广泛关注．采用化学共沉淀法制备了具有尖晶石结构的铁酸盐,经高温煅烧使其形成了初始分解温度仅为839Y3的高活性氧缺位铁酸铜（CuFe2O4-δ）,设计并开发了两步骤热化学循环制氢反应试验装置．利用XRD,DTA—TG,AAS和GC等分析方法和实验技术,对制备出的氧缺位铁酸铜样品的结构、性质、化学组成及氧缺位程度占值进行了详细的研究,并对CuFe2O4-δ分解水制氢过程和循环性能进行了探讨和研究．     

高温煤气脱硫：Ⅱ.铁锌基脱硫剂再生工艺条件的研究

用自制的铁酸锌脱硫剂对再生温度，再生氢气做了研究，结果表明：脱硫剂在６５０℃或７００℃，再生效果相近，再生率接近于１．０在下次循环中硫化反应活性高；在６００℃时，再和互小于１．０。     

铁酸镍纳米微粒的固相合成及其催化性能

微波辐射;乙苯脱氢;铁酸镍纳米微粒的固相合成及其催化性能     

尖晶石型铁酸镉催化苯酚过氧化氢羟化作用的研究

尖晶石型铁酸镉催化苯酚过氧化氢羟化作用的研究于剑锋，杨宇，吴通好，孙家锺（吉林大学化学系理论化学研究所，长春，１３００２３）关键词尖晶石型铁酸镉，苯酚过氧化氢羟化，苯二酚由低浓度的Ｈ２Ｏ２羟化苯酚制苯二酚（ＤＢＨ）的研究已有许多报道［１～４］，但其催...     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

解决能源问题的新途径——光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。     

黄酮化合物的合成研究进展

黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.