ZrO4/SiO2-Al2O3催化肉桂醛MPV转移加氢性能

以九水合硝酸铝（Al（NO₃）₃·9H₂O）与正硅酸乙酯（TEOS）为前驱盐,采用溶胶-凝胶法制备一系列不同Al₂O₃含量的SiO₂-Al₂O₃复合氧化物,并通过浸渍硝酸氧锆引入ZrO₂,制备ZrO₂/SiO₂-Al₂O₃复合氧化物催化剂,考察催化剂在肉桂醛（CAL）MPV转移加氢中的催化性能,并结合N₂物理吸附、X射线粉末衍射（XRD）、傅里叶变换红外光谱（FTIR）、NH₃-程度升温脱附（NH₃-TPD）、Py-原位红外（Py-IR）等技术,研究催化剂结构、织构以及表面性质与其催化性能间的构效关系.研究表明,所制备的催化剂均以L酸为主,并含有少量B酸中心,这使得加氢产物以肉桂醇（COL）为主,并含有少量1-苯丙烯-2-丙基醚（CPE）.Al₂O₃含量不仅影响催化剂表面的酸中心数量,而且对催化剂的织构参数有较大影响.随Al₂O₃含量的增加,催化剂表面L酸与B酸中心均有所增加,而孔径则持续变小,这使得催化反应呈现CAL转化率先增加后减少、目标产物COL选择性先稍有减小后有所增加的趋势.在Si/Al比为2时,催化剂具有最优的催化性能,优化反应条件下,CAL转化率达96%,目标产物COL选择性达90%.     

Theoretical study of the reaction of Cu with OCS

The reactivity of Cu⁺ with OCS on both singlet and triplet potential energy surfaces (PES) has been investigated at the UB3LYP/6-311+G(d) level. The object of this investigation was the elucidation of the reaction mechanism. The calculated results indicated that both the C–S and C–O bond activations proceed via an insertion–elimination mechanism. Intersystem crossing between the singlet and triplet surfaces may occur along both the C–S and C–O bond activation branches. The ground states of CuS⁺ and CuO⁺ were found to be triplets, whereas CuCO⁺ and CuCS⁺ have singlet ground states. The C–S bond activation is energetically much more favorable than the C–O bond activation. All theoretical results are in line with early experiments.     

Theoretical study of the reaction of Ni with OCS

The reactivity of Ni⁺ with OCS on both doublet and quartet potential energy surfaces (PES) has been investigated at the B3LYP/6-311+G(d) level. The object of this investigation was the elucidation of the reaction mechanism. The calculated results indicated that both the CS and CO bond activations proceed via an insertion–elimination mechanism. Intersystem crossing between the doublet and quartet surfaces may occur along both the CS and CO bond activation branches. The ground states of NiS⁺ and NiO⁺ were found to be quartets, whereas NiCO⁺ and NiCS⁺ have doublet ground states. The CS bond activation is energetically much more favorable than the CO bond activation. All theoretical results are in line with early experiments.     

Theoretical investigation on the reaction of N2O and CO catalyzed by Fe(C6H6)

The reaction of N₂O with CO, catalyzed by Fe⁺(C₆H₆) and producing N₂ and CO₂, has been investigated at the UB3LYP/6-311+G(d) level. The computation results revealed that the reaction of Fe⁺(C₆H₆), N₂O and CO, is an O-atom abstraction mechanism. For the reaction channels, the geometries and the vibrational frequencies of all species have been calculated and the frequency modes analysis also have been given to elucidate the reaction mechanism. On the basis for geometry optimizations, the thermodynamic data of these reactions channels have been calculated using the statistical theory at 295.15 K and pressure of 0.35 Torr. Using Eyring transition state theory with Wigner correction, the activation thermodynamic data, rate constant and frequency factors for the these reaction channels also have been given. The results showed that CO and N₂O do not react without catalyst and Fe⁺(C₆H₆) can excellently mediate the reaction of N₂O and CO.     

源于膨胀波边界层理论中的一类奇异边值问题

对源于膨胀波边界层理论中的一类奇异边值问题进行了研究,利用单调逼近方法得到了满足物理意义上正解的存在性和唯一性的充分条件,同时给出了用速度比例参数表示的壁摩擦的估计公式, 利用打靶法技巧得到了问题的数值解.数值结果证明了估计公式的可靠性和有效性.     

2-（3,5-二氯-2-吡啶偶氮）-5-二乙氨基酚分光光度法测定啤酒中微量铬的研究

在0.09—0.16mol·L-1硫酸介质中,Cr2O72-与2-（3,5-二氯-2-吡啶偶氮）-5-二乙氨基酚作用,形成二离子缔合物,最大吸收波长533nm,表观摩尔吸光系数为为4.51×104L·mol-1·cm-1,铬含量在0—3.3μg·mL-1内符合比耳定律,用于啤酒样品中微量铬的测定,结果满意。     

陕北榆神府矿区地质环境现状及采煤效应影响预测

以我国西部特大型煤田榆神府矿区为例 ,从环境工程地质学角度分析了该区煤炭资源开发中主要的环境工程地质问题 ,并进行了综合地质环境质量现状和采后变化预测评价。研究结果对该区煤炭资源合理开发宏观决策和规划设计有直接指导意义。     

Ni/SiO2-Al2O3催化乙酰丙酸加氢制γ-戊内酯

采用溶胶-凝胶法制备了一系列不同Al₂O₃含量的SiO₂-Al₂O₃复合氧化物,以该系列复合氧化物为载体,采用等体积浸渍法制备了Ni负载量15%（重量百分比）的催化剂,用于催化乙酰丙酸加氢制γ-戊内酯.采用N₂物理吸附、X射线衍射（XRD）、H₂程序升温还原（H₂-TPR）、H₂程序升温脱附（H₂-TPD）、NH₃程序升温脱附（NH₃-TPD）和吡啶吸附红外（Py-IR）等手段对催化剂进行了表征.结果表明,不同载体催化剂的活性组分分散度及表面酸性质存在明显差异,显著影响了催化剂吸附、活化H₂与C=O键的能力,进而影响了催化剂的乙酰丙酸加氢活性.其中,Ni/SiO₂-Al₂O₃催化剂上的L酸中心能够促进C=O键的吸附、活化,与金属Ni上的H₂吸附活性位协同作用,大大提高了乙酰丙酸加氢活性.因此,具有最多L酸中心和丰富H₂吸附活性位的Ni/SiO₂-8Al₂O₃催化剂表现出最高的乙酰丙酸加氢活性,在180℃、4 MPa氢气压力下,乙酰丙酸转化率达到90.5%,目标产物γ-戊内酯选择性为100%.     

戊唑醇银配合物的合成、晶体结构及生物活性研究

合成了新配合物[AgL2]NO3(L=(RS)-1-(4-氯苯基)-4,4-二甲基-3-(1H-1,2,4三唑-1-基甲基)戊-3-醇,戊唑醇)。应用元素分析、IR光谱及X射线单晶衍射方法对配合物的组成及结构进行了表征。该配合物晶体属单斜晶系,C2/c空间群,晶胞参数:a=3.698 9(7)nm,b=0.902 8(2)nm,c=1.122 8(2)nm,β=103.66(3)°,V=3.643 3(13)nm3,Dc=1.432 g.cm-3,Z=4,F(000)=1 624,μ=0.748mm-1。研究了配合物及戊唑醇对烟草赤星病菌和苹果树干腐病菌的抑制作用及对小麦生长调节作用。实验结果表明:配合物不利于小麦的发芽和生长,但具有更优越的杀菌性能。