γ-Mo2N催化剂上的乙炔选择加氢

 采用固定床连续流动反应器对γ－Mo2N催化剂上的乙炔加氢反应进行了研究．在150℃的反应温度下,乙炔的转化率为95％,乙烯的选择性达到80％,乙烷和丁烯的选择性分别为4％和10％．反应温度和空速的变化对反应产物的选择性没有明显的影响．在同样的反应条件下,钯催化剂上乙炔加氢反应的主要产物是乙烷,产物组成随反应温度和空速的变化而变化．对γ－Mo2N上的乙炔选择加氢生成乙烯的机制进行了解释,认为γ－Mo2N表面上滞留的强吸附的碳氢物种可能有利于乙炔高选择性地生成乙烯．     

纳米Cr2O3系列催化剂上CO2氧化乙烷脱氢制乙烯反应

 采用溶胶－凝胶法和共沸蒸馏法耦合技术制备了纳米Cr2O3催化剂，并采用共沉淀法和共沸蒸馏法耦合技术制备了纳米Cr2O3／Al2O3，Cr2O3／ZrO2和Cr2O3／MgO复合催化剂．应用BET，XRD，XPS，TPR和TEM等物理化学方法对催化剂的结构和物化性质进行了表征，并考察了该系列催化剂上CO2氧化乙烷脱氢制乙烯的反应性能．结果表明，纳米Cr2O3催化剂上乙烷和CO2的转化率均明显高于常规Cr2O3催化剂，但乙烯的选择性低于常规Cr2O3催化剂；纳米复合催化剂中的复合成分显著影响催化剂的催化性能．其中，10％Cr2O3／MgO纳米复合催化剂在温度为973K时，乙烷转化率和乙烯选择性分别可达到61．54％和94．79％．纳米催化剂表面Cr的还原性以及Cr6＋／Cr3＋比值是影响乙烷转化率和乙烯选择性的重要因素．     

γ-Mo_2N催化剂上的乙炔选择加氢

采用固定床连续流动反应器对γ Mo2 N催化剂上的乙炔加氢反应进行了研究 .在 15 0℃的反应温度下 ,乙炔的转化率为 95 % ,乙烯的选择性达到 80 % ,乙烷和丁烯的选择性分别为 4%和 10 % .反应温度和空速的变化对反应产物的选择性没有明显的影响 .在同样的反应条件下 ,钯催化剂上乙炔加氢反应的主要产物是乙烷 ,产物组成随反应温度和空速的变化而变化 .对γ Mo2 N上的乙炔选择加氢生成乙烯的机制进行了解释 ,认为γ Mo2 N表面上滞留的强吸附的碳氢物种可能有利于乙炔高选择性地生成乙烯 .     

碳纳米管对非晶态NiB合金催化剂性能的影响

采用化学还原法制备了非晶态NiB合金，用CNTs-1、CNTs-2、y-Al2O3作载体制备了负载型非晶态NiB合金催化剂．以乙炔选择性加氢为目标反应考察了催化活性和选择性，用TEM、TPD等方法对催化剂进行了表征．TEM结果表明，粒径为8～10nm的NiB粒子均匀分散在CNTs-1外表面，大部分粒径为12～14nm的NiB颗粒在CNTs-2内腔生长，而y-Al2O3载体未能有效提高NiB分散度．用CNTs-1将NiB负载化，明显提高了NiB催化剂乙炔加氢活性．CNTs-1、CNTs-2和y-Al2O3载体对比，CNTs-2作载体促进了催化剂对氢的吸附，减弱了乙炔的吸附，提高了加氢活性和乙烯选择性．     

糠酸加氢负载型催化剂的制备及催化性能

选用不同的贵金属钌、铑、钯、铂，不同的金属担载量，不同的催化剂载体氧化硅、活性炭（AC）、γ-三氧化二铝等，制备了多种负载型催化剂，采用连续操作的固定床微型反应器评价了它们的糠酸加氢催化性能．研究表明，金属钯的性价比最好，钯的最佳担载量为0．8％，最适宜的催化剂载体是γ-三氧化二铝．催化剂0．8％Pd／γ-Al2O3，具有良好的催化活性和选择性．优化了该催化剂上糠酸加氢的反应条件，结果表明，在1．0MPa、150oC、氢气空速2000h^-1、糠酸的乙酸乙酯溶液的空速4．0h^-1的条件下，糠酸转化率达100％，四氢糠酸选择性为99．0％．     

微波等离子体下一氧化碳氢化制乙炔反应中产物的选择性研究(英文)

采用微波等离子体技术研究了一氧化碳氢化制乙炔反应的产物选择性。对影响乙炔选择性的几个因素,如微波输入功率、反应物的比例和体系压力进行了研究。乙炔的选择性随着微波输入功率的增加,反应物比例和体系压力的降低而增大。在最佳条件下,乙炔的选择性可达到９５．８７％,甲烷选择性的变化规律和乙炔相反,乙烯和乙烷的选择性很低。等离子体中的电子温度（或能量）和密度采用了静电悬浮双探针诊断,电子密度和能量受微波输入功率和体系压力的影响。在反应中,电子能量决定化学反应是否进行,电子密度决定产物的组成。根据自由基反应理论解释了乙炔选择性在Ｈ２＋ＣＯ等离子体化学反应中随影响因素的变化规律。     

密度泛函理论计算研究表面应力对钯催化乙炔选择性加氢活性与选择性的影响（英文）

在石油催化裂解过程中,除了生成乙烯、丙烯及丁烯等烯烃,还会产生部分炔烃.目前工业上通常采用炔烃选择性加氢转化为对应的单烯烃,以除去其中炔烃.由于产品烯烃中的炔烃等杂质含量需极低,这就对用于加氢催化剂的活性和选择性提出了很高的要求,即催化剂需要选择性吸附炔烃并加氢,而不损失其中的烯烃.经过前期大量的基础研究工作,目前工业中炔烃选择性加氢应用最广泛的催化剂是负载型钯基催化剂.然而,单独的钯金属选择性并不理想,因而对其选择性以及活性进行调控成为了当前关注的研究课题.本文采用密度泛函理论计算结合微观反应动力学模拟手段,研究了钯金属表面应力存在条件下的活性与选择性,以及形成次表层物种的可能性和形成后的活性与选择性.研究发现,改变钯金属的晶格参数与表面应力,反应物、表面反应中间体和产物的吸附能都会产生相应的变化,且吸附能与晶格参数的变化存在线性关系,晶格参数越大,吸附越强.利用表面反应过渡态能量与初始态能量之间的线性关系,相应的乙炔加氢生成乙烯的反应速率可以通过微观反应动力学模拟得到.结果显示,不同晶格参数的钯催化剂催化乙炔加氢生成乙烯的反应活性位于相应火山型曲线的强吸附侧,即减弱乙炔和氢的吸附强度可提高乙烯的生成速率.在此基础上,本文研究了不同表面应力的钯催化剂在次表面吸附不同覆盖度碳原子和氢原子的情况,发现晶格参数越大越有利于碳原子和氢原子在次表面的吸附.同时,研究发现在次表面碳掺杂的条件下,不同表面应力条件下的钯催化剂的活性均有所增强.此外,由于乙烯在所有研究的钯催化剂表面脱附比进一步加氢容易,因而乙烯都可以选择性生成.     

Cr2O3-Co3O4／SiO2对十八醇氧化生成十八酸反应的催化性能

 制备了一系列不同Cr／Co比例的Cr2O3－Co3O4／SiO2催化剂，并用XRD，FT－IR和BET等手段对催化剂进行了表征；考察了催化剂对十八醇氧化生成十八酸反应的催化性能，及反应条件（反应温度和反应时间）对催化性能的影响，确定了最佳反应条件．结果表明，金属硝酸盐在773K焙烧后转变成相应的氧化物并负载于二氧化硅上．Cr2O3－Co3O4／SiO2催化剂对十八醇氧化反应有很高的催化活性，十八酸选择性最高可达99．93％，收率可达52．44％．Cr2O3－Co3O4／SiO2催化剂的活性明显高于单一的Cr2O3／SiO2或Co3O4／SiO2催化剂     

助剂α-Sb2O4对杂多化合物催化剂选择氧化异丁烷的影响

采用组合法制备了具有Keggin结构的杂多化合物催化剂，采用FTIR、UV-VIS-DR、H2-TPR、BET、TG-DTA和SEM对合成的催化剂的结构和性质进行了研究．探讨了催化剂中助剂α-Sb2O4含量对异丁烷选择性催化氧化的影响．并考察了反应温度对催化剂的催化性能影响．实验表明，助剂含量为8．3％，在C4H10／O2／N2／H2O=1／2．6／6／1，GHSV为910h^-1，温度为380℃的条件下，甲基丙烯酸的收率可达10．4％，选择性为44．3％．     

负载型MoOx和VOx催化剂甲醚选择氧化制甲醛反应

考察了负载型MoOx和VOx催化剂上二甲醚选择氧化制甲醛反应的性能．结果表明，两类催化剂在低温(240～320℃)下都具有良好的催化性能，VOx催化剂比MoOx催化剂所需的反应温度低，300℃下在VOx／r-Al2O3催化剂上二甲醚转化率可达20％，甲醛选择性可达70％．载体对催化剂性能有较大的影响，对于VOx催化剂，使用酸性载体时二甲醚转化率和甲醛选择性更高．催化剂的稳定性较好，反应17h后，VOx／r-Al2O3催化剂上未检测到有积碳生成．     

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.     

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。     

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.

     

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.     

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.     

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^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。