Cu-V-O氧化物催化燃烧甲苯的活性和抗硫性

采用溶胶-凝胶法制备一系列不同Cu/V比例的Cu-V-O催化剂,利用XRD、BET、H₂-TPR等手段对催化剂进行了表征,并考察其催化燃烧甲苯的活性和抗硫性。结果表明,适量的Cu掺杂会提高催化剂比表面积,而且Cu-V可以形成Cu₃V₂O₈晶型结构,使V₂O₅晶格氧活动增加,提高催化剂氧化-还原能力。其中,Cu_0.15V_0.85催化剂表现出最佳的活性和抗硫性;通过TiO₂负载可以进一步提高催化剂对甲苯的催化燃烧活性和抗硫性。     

交联聚乙烯基吡咯烷酮快速前处理方法结合液相色谱-串联质谱分析红葡萄酒中酪蛋白过敏原

建立了红葡萄酒酪蛋白过敏原的质谱分析方法。选择专一性SRM离子对,建立3种亚型酪蛋白α-S1,α-S2,β的质谱定性与定量方法;利用交联聚乙烯基吡咯烷酮(PVPP)处理红葡萄酒有效提取蛋白,并直接快速酶解,使前处理缩短到2 h以内。结果表明,酪蛋白的回收率提高到80%以上,检出限达10μg/L。     

微波辅助中空纤维液相微萃取-液相色谱-串联质谱法同时快速测定牛奶中27种抗生素残留

采用微波辅助中空纤维液相微萃取的样品前处理方法,在一段中空纤维管内注入正辛醇-甲苯(1∶1,V/V)作为接受相,两端封口后浸入供相溶液进行萃取。在700 r/min连续磁力搅拌和间歇微波辐照下,12.67 min即可完成27种目标化合物同时萃取。建立了微波辅助中空纤维液相微萃取联用液相色谱-串联质谱同时测定牛奶中27种抗生素(9种喹诺酮、15种磺胺、3种大环内酯)痕量残留的方法。以基质标准曲线外标法定量,线性范围为0.2!5.0"g/kg,相关系数均大于0.99(n=3),定量限(LOQ,S/N=10)在0.036!0.568"g/kg范围内。以0.5、1.0和2.0"g/kg添加浓度水平进行方法验证,回收率为49.0%~115.0%,相对标准偏差为0.89%~21.1%。     

超临界流体中制备微孔和介孔结构金属有机框架负载Ru及其催化性能

以柠檬酸为螯合剂,十六烷基三甲基溴化胺为表面活性剂,通过ZrOCl2·8H2O 与对苯二甲酸 (H2BDC) 反应制备了同时具有微孔和介孔结构的Zr基金属有机骨架材料(Zr-MOF),并在超临界CO2-甲醇流体中将 Ru 负载于 Zr-MOF 上, 制备了 Ru@Zr-MOF催化剂,采用傅里叶变换红外光谱、X射线粉末衍射、透射电子显微镜、热重分析、N2吸附-脱附、X射线光电子能谱和电感耦合等离子体发射光谱对催化剂进行了表征,研究了该催化剂在苯及其同系物加氢反应中的催化性能. 结果表明,Ru纳米金属颗粒均匀地分散在Zr-MOF载体上,平均粒径约为2.3nm,在苯及其同系物的加氢反应中表现出很高的催化活性和稳定性.     

碳-硅复合介孔磺酸催化剂的制备及其在缩醛(酮)反应中的应用

采用浸渍法将糠醇负载在铝改性的SBA-15介孔孔道中,经550℃不完全碳化制备了结构规整、含多苯环的中空管状硅碳复合介孔材料.结果表明,通过温和磺酸化作用可使磺酸基团成功取代在多苯环上,其酸量随着多苯环涂层厚度变化在0.38~0.84 mmol/g范围内可控调变.相比于蔗糖作为糖源的复合固体酸,所制碳多苯环-硅酸催化剂具有中空碳纳米管堆积的类似CMK-5介孔结构,以及较大的反应空间、稳定的机械性能、较高的比表面和大量可以接触的质子酸中心,因而在大分子缩醛(酮)反应中表现了良好的催化性能.     

A Trinuclear Ni(Ⅱ) Mixed-ligand Complex Containing Pentadentate N-butylsalicylhydrazide and Monodentate Imidazole:Synthesis, Characterization and Crystal Structure

A novel trinuclear nickel(Ⅱ) complex [Ni3(bushz)2(Himdz)2(H2O)2]?2DMF (1, bushz=N-butylsalicylhydrazide, Himdz=imidazole, DMF=N,N-dimethyl-formamide) has been synthesized and characterized by X-ray single-crystal diffraction characterization. Complex 1 crystallizes in the monoclinic system, space group P21/c with a=7.706(7), b=14.882(6), c=18.639(6) , β=108.08(2)o, V=2032(1) 3, Dc=1.525 g/cm3, Mr=932.95, Z=2, F(000)=972, μ=1.442 mm-1, the final R=0.0359 and wR=0.0771. The three nickel(Ⅱ) atoms in 1 are arranged in a strictly linear structure and exhibit alternating square-planar and octahedral geometries. The complex is connected to form a supramolecule with an infinite three-dimensional network through intermolecular hydrogen bonds. The electrochemical studies reveal that redox of Ni3+/Ni2+ in the complex is a quasi-reversible process. The thermal stability of the title complex was also studied.     

Syntheses and Crystal Structures of Two New Macrocyclic Compounds

Two new macrocyclic compounds, [Cu2(L)2](ClO4)4·2CH3OH (1) and [Cu(L)](ClO4)2·2H2O (2) (L = 1,3,10,12,15,18-hexaazatetracyclodocosane) were synthesized by condensation reactions involving amines and formaldehyde in the presence of copper anion. Compound 1 crystallizes in triclinic, space group Pí with a = 10.442(2), b = 14.197(3), c = 17.388(4), α = 91.218(4), β = 90.69(3), γ = 93.756(4)o, V = 2520.4(9)3, Z = 2, F(000) = 1260, Dc = 1.589 Mg/m3, Mr = 1205.92, μ = 1.137 mm-1, λ = 0.71073, the final R = 0.0668 and wR = 0.1573 for 9703 observed reflections with I > 2σ(I). Compound 2 crystallizes in monoclinic, space group C2/c with a = 16.911(2), b = 11.4172(15), c = 27.059(4), β = 107.787(2)o, V = 4974.7(12)3, Z = 8, F(000) = 2504, Dc = 1.610 Mg/m3, Mr = 602.92, μ = 1.155 mm-1, λ = 0.71073 , the final R = 0.0419 and wR = 0.1131 for 4374 observed reflections with I > 2σ(I).     

Effect of Plasma Treatment on the Structures and Properties of Konjac Glucomannan Film

To understand the effect of plasma treatment on the Konjac glucomannan film, the nitrogen plasma was injected into the film by ion beam injection machine in this study. The structures and properties of Konjac glucomannan film after plasma treatment were analyzed by Infrared spectroscopy, Raman spectrum, X-ray, ect. The result showed that nitrogen groups appeared in the KGM molecular chain and part of this chain fractured, and the number of hydrogen bonds increased after the treatment of plasma. The form of KGM molecule remained amorphous non-crystalline state, but the crystalline region was increased and became more ordered. The mechanical property of tensile strength and breaking elongation was improved, while the WVP was decreased. The nitrogen groups were grafted on the KGM molecular chain after plasma treatment, which led to the improvement of the properties of KGM film.     

Effect of Precursor Drying Process on the Properties of LiFePO4/C Composite with Low Carbon Content

<正>Properties of two LiFePO_4/C composites with low carbon content synthesized from precursors dried by spray drying and blast drying are investigated by scanning electron microscopy, X-ray diffraction, Raman spectroscopy and electrochemical measurements. The two samples have a different morphology and particle size, while the structure of LiFePO_4 is unaffected. The LiFePO_4/C composite prepared from the precursor dried by blast drying has a much lower surface resistance and a much better rate capability because the deposited carbon is more graphite-like and more conductive. The cycling performance is also much better for the LiFePO_4/C composite prepared from the precursor dried by blast drying because only a slight impedance growth is involved upon cycling. These results suggest that the precursor drying process has a significant impact on the properties of LiFePO_4/C composite, and its effect is highly dependent on the carbon content.