硝基苯加氢合成对氨基酚用负载铂催化剂的制备

 用甲醛还原沉积法制备了活性炭负载的铂催化剂（Pt／AC）和不\r\n同载体负载的铂催化剂，并考察了催化剂对硝基苯加氢制备对氨基酚反\r\n应的催化性能．结果表明，还原Pt（Ⅳ）的甲醛用量是影响催化剂性能\r\n的关键因素，甲醛必须过量而且存在一个最佳值．增加催化剂的铂负载\r\n量，不能有效提高加氢反应速度，反而易降低对氨基酚选择性；低铂负\r\n载量催化剂具有较高的活性、选择性及稳定性．XPS和TEM表征结果表明\r\n，金属铂集中分布于活性炭颗粒外部，其颗粒大小介于2～12nm间．炭\r\n载体催化剂的活性和选择性明显高于金属氧化物载体催化剂．掺入适量\r\n的Mg可显著提高Pt／AC催化剂的活性和选择性．     

氧化铝负载钌基氨合成催化剂的制备条件及载体改性

 利用等体积浸渍法制备了氧化铝负载钌基氨合成催化剂．考察了\r\n氢氧化铝的焙烧温度，催化剂的还原温度，助剂K、Ba和Sm的添加，以\r\n及用MgO和BaO改性氧化铝载体等对催化剂活性的影响．通过XRD，N2物\r\n理吸附和CO2化学吸附等方法表征了载体的物相结构、比表面积和表面\r\n碱性．研究结果表明，氧化铝表面碱性随着氢氧化铝焙烧温度的升高而\r\n增大是催化剂活性升高的主要原因，载体比表面积的降低对催化剂活性\r\n的影响相对较小．助剂K、Ba和Sm的加入显著地提高了催化剂的活性，\r\n同时助剂Ba和Sm还减弱了强吸附氢对氮吸附的抑制作用，明显提高了催\r\n化剂的高压活性．用MgO改性氧化铝载体降低了其比表面积，但是显著\r\n地提高了载体的表面碱性和催化剂的活性．BaO改性的氧化铝载体的比\r\n表面积、表面碱性及其负载的钌基催化剂的活性随着BaO含量的增加先\r\n升高后降低，当BaO摩尔含量为7．7％时，催化剂活性最高．     

沸石负载的钒络合物催化剂对烷烃氧化反应的催化性能

 将钒氧吡啶甲基络合物VO（pic）2负载于Y及ZSM－5沸石分子筛\r\n中，制备出沸石负载的钒络合物催化剂．用X射线衍射、电子自旋共振\r\n、红外光谱和元素分析等方法对催化剂进行了表征．结果表明，VO（p\r\nic）2络合物确实负载于分子筛孔道内，负载后的络合物仍保持着原来\r\n的结构．考察了催化剂对正己烷和环己烷氧化反应的催化性能，发现沸\r\n石分子筛负载的VO（pic）2络合物催化剂保留有络合物原有的催化性能\r\n，虽然催化活性有所下降，但显示出较好的形状选择性．与未负载的络\r\n合物相比，NaY和ZSM－5沸石负载的VO（pic）2络合物催化剂对正己烷\r\n氧化反应的伯醇选择性分别提高了2～3倍和5～6倍．     

制备条件对Al1P1.30Ti0.30Si0.17体系催化剂性能的影响

 从制备催化剂的原料、沉淀剂种类、铝沉淀物终点的pH值、水量\r\n及原料的加入顺序等方面考察了制备条件对AlP1．30－Ti0．30Si0．1\r\n7体系的结构及催化性能的影响．结果表明，以自制新鲜氢氧化铝为铝\r\n源，以硅溶胶为硅源，以钛酸丁酯为钛源，以氨水为沉淀剂，在pH＝6\r\n．2，c（Al3＋）＝0．64mol／L（V（H2O）＝200ml）的条件下，采用\r\n通常的沉淀方法可制备出性能优良的催化剂．催化剂的酸性是影响其催\r\n化性能的主要因素，主产物选择性与酸强度有关，酸强度高的催化剂具\r\n有较低的主产物选择性；催化剂的活性与其孔径及表面酸量有关；催化\r\n剂中的B酸中心是反应可能的活性中心．     

钼催化剂上甲醇直接气相羰基化活性与吸附的关系

 制备了一系列非负载的钼催化剂，考察了催化剂上甲醇直接气相\r\n羰化活性与反应物及产物吸附的关系．结果发现，催化剂的制备方法对\r\n甲醇直接气相羰化活性的影响很明显，以纯二硫化钼试剂制备的催化剂\r\n，甲醇转化率与羰化产物乙酸甲酯的选择性最低；以三氧化钼气相还原\r\n硫化制备的催化剂，其羰化活性较低；以钼酸铵溶液经硫化铵溶液或硫\r\n化氢气体硫化制得的催化剂，其性能明显优于前两种，尤以钼酸铵经硫\r\n化铵溶液硫化制得的催化剂的性能最佳．催化剂的羰化活性明显依赖于\r\n催化剂的吸附性能，羰化活性高的催化剂不仅吸附CO的量大，而且对甲\r\n醇和乙酸甲酯的吸附量也明显较大．     

表面键联型TiO2/SiO2固定化催化剂的结构及催化性能

 采用浸渍法制备了表面键联型TiO2／SiO2固定化光催化剂．XRD\r\n,FT－IR,XPS和BET比表面积测定结果表明,TiO2通过Ti－O－Si联结\r\n负载于多孔硅胶的表面,由此提出TiO2／SiO2的结构模型．考察了多孔\r\n硅胶的粒度及氧化钛负载量对催化剂活性的影响．对活性艳红K－2G（\r\nR15）的光催化脱色反应,最佳的光催化剂30％TiO2／SiO2（Ims30）比\r\nB－TiO2粉末的催化速率快3倍．随着载体粒度的减小,催化剂的比表面\r\n积增大,催化活性升高;多孔硅胶不仅起着支持体的作用,而且具有分\r\n散的作用;多孔硅胶具有很好的透光性．经ξ－电位测定,所制备催化\r\n剂的等电点为3．0pH单位,表明催化剂表面呈酸性．     

Re/HZSM-5体系上的甲烷无氧芳构化反应

 与Mo／HZSM－5相比，Re／HZSM－5也是较好的甲烷无氧芳构化催\r\n化剂，其初活性较高，但随着反应的进行，催化剂失活的速率较快．通\r\n过NH3－TPD，H2－TPR和MASNMR等手段，对催化剂的酸性和分子筛骨架\r\n铝的变化以及铼物种的还原性能进行了研究．结果表明，催化剂酸性的\r\n在反应中起着重要的作用，但不同铼担载量的催化剂酸性的变化比较复\r\n杂，不同于Mo／HZSM－5体系．总的来看，并不是酸性越强或酸量越多\r\n，催化剂的催化性能就越好；催化剂的酸性和酸量都有一个最佳值．担\r\n载铼物种后，铼物种可与分子筛的骨架铝发生强烈的相互作用，最终导\r\n致骨架脱铝．Re／HZSM－5催化剂具有较高的低温活性，在较低温度下\r\n可被还原性气氛还原，且还原后的活性物种单一．     

载体和担载酸对乙烯直接氧化合成乙酸反应的影响

 在固定床流动反应器上研究了Pd－酸／载体体系催化乙烯直接氧\r\n化合成乙酸的反应，并对载体相同但担载酸强度不同的催化剂的催化活\r\n性进行了比较．结果表明，担载酸的强度明显影响催化剂的活性，酸强\r\n度越大其催化活性越高．用NH3－TPD和异丙醇脱水探针反应表征了二氧\r\n化硅、活性碳和酸性白土三种载体担载的Pd－H4SiW12催化剂的酸性，\r\n并测试了三种催化剂的催化活性．结果表明，载体通过影响担载酸的强\r\n度而影响催化剂的活性，载体上的强酸中心越多，催化剂的活性越高．\r\n测定了二氧化硅、活性碳和酸性白土三种载体担载的Pd－H4SiW12催化\r\n剂上Pd的分散度，并与其催化活性相关联．结果表明，决定乙烯直接氧\r\n化生成乙酸反应活性的主要因素是催化剂的酸强度而不是Pd的分散度．     

用于丁烷选择氧化制顺酐的铈锆复合钒磷氧催化剂的研究

 在钒磷氧（VPO）催化剂中添加适量铈锆复合氧化物，得到了一\r\n种新型的铈锆复合钒磷氧催化剂．该催化剂对丁烷选择性氧化制顺酐反\r\n应的催化性能比纯VPO催化剂有了显著提高．在丁烷／空气共进料反应\r\n条件下，其顺酐收率比纯VPO催化剂提高了一倍；在无氧反应条件下，\r\n其可参与选择性氧化制顺酐的晶格氧量为纯VPO催化剂的2．2倍．BET比\r\n表面积测试、X射线衍射、钒平均价态测定和程序升温实验等表征结果\r\n表明，混合在催化剂活性相中的少量铈锆复合氧化物参与了VPO体系的\r\n氧化还原过程，并起到了以下两方面的作用：（1）促进了（VO）2P2O\r\n7相的形成，稳定了钒的平均价态，有利于最终形成晶相结构良好和反\r\n应性能稳定的VPO催化剂；（2）显著提高了VPO催化剂的氧化还原性能\r\n，大大增加了催化剂的可逆储氧量．     

不同方法制备的Ni／ZrO2-CeO2-Al2O3催化剂对CH4-CO2重整反应的催化性能

 采用水热合成法、溶胶凝胶法和共沉淀－负载法制备了相同NiO含量的Ni／ZrO2－CeO2－Al2O3催化剂，考察了它们在CH4－CO2重整反应中的催化性能及稳定性，测定了积碳量．用CO2程序升温脱附方法测试了它们的CO2吸附性能，用H2程序升温脱附方法测试了表面Ni的分散度．结果表明，随温度升高，CH4和CO2转化率降低的顺序是：溶胶凝胶法≈共沉淀－负载法＞水热合成法，并且反应产物中n（CO）／n（H2）比随温度升高而降低．水热法和共沉淀－负载法制备的催化剂稳定性好，且前者的活性比后者高；溶胶凝胶法制得的催化剂活性较高，但易失活．积碳量大小顺序是：水热法＞溶胶凝胶法＞共沉淀－负载法．与其他方法制备的催化剂相比，水热法制备的催化剂对CO2的吸附量更大，\r\n而且积碳主要存在于载体上，从而保证了催化剂的稳定性．     

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。     

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.     

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.     

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.     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

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.