铝基板的界面扩散对薄膜型TiO2光催化活性的影响

以钛酸四丁酯为前驱体, 采用溶胶-凝胶法在铝基板表面制备了纳米晶TiO2薄膜. 运用XRD、SEM和XPS对制得的薄膜进行表征, 并测试了薄膜光催化降解亚甲基蓝(MB)的活性. 结果表明, TiO2薄膜样品在450 ℃焙烧30 min后, 晶粒排列比较致密, 粒径为10-20 nm, 并与铝基板紧密结合; 薄膜与铝基板发生了明显的界面扩散, 薄膜中的Al元素来自铝基板的界面扩散, 且界面层很宽, 扩散层厚度约为75 nm; 界面扩散的发生直接导致了TiO2薄膜的光催化活性下降. 但随着薄膜厚度增加, 铝基板对TiO2薄膜降解亚甲基蓝催化活性的影响不断减小.     

交替马来酸酐共聚物多缩乙二醇酯盐络合物的离子传导性

交替马来酸酐共聚物多缩乙二醇酯盐络合物的离子传导性丁黎明，林云青，周子南，王佛松（中国科学院长春应用化学研究所，长春，１３００２２）关键词高分子固体电解质，离子电导率，玻璃化转变温度，离子传输，ＶＴＦ方程１９７３年，Ｐ．Ｖ．Ｗｒｉｇｈｔ等人［１］首次...     

Mn/Se,MnO2/Se和Mn/SeO2体系形成的团簇离子的质谱研究

用飞行时间质谱法研究了激光直接溅射Mn/Se混合样品产生的二元团簇、团簇的光解行为及溅射MnO₂/Se和Mn/SeO₂样品产生的团簇正负离子。在Mn-Se二元团簇中,(Muse)_n⁺是正离子的主要组分,[(Muse)nSe]^-是负离子的主要组分。当n<5时,(Muse)_n⁺的紫外光解有多种通道;n≥5时光解以剥落MuSe方式进行。激光直接溅射MnO₂/Se,Mn/SeO₂两种体系产生的正负离子极为相似,符合团簇的气相聚合生长机理。正离子中(Mno)_n⁺是主要组分,负离子中Se_n^-,(Se_nO)^-和(SéO₃)^-是主要组分。     

聚甲基丙烯酸三氟乙酯单体与分子链在金属有机框架中吸附及取向特性的理论研究

本文结合分子动力学、密度泛函理论和蒙特卡洛方法,研究了光学损耗低的氟化聚合物单体分子甲基丙烯酸三氟乙酯（TFMA）及其分子链在[Zn2(BDC)2TED]n和[Zn2(BPDC)2TED]n两种结构有序的金属有机框架（MOFs）材料中的吸附特性,得到相应的吸附数量和取向程度,以探索提高聚合物材料双折射性的有效途径。通过分析结果得出影响TFMA单体分子在这两种MOF孔道中吸附及取向特性的三个因素：a）由于MOF孔道壁是由金属离子和有机配体组成的极性表面,MOF孔壁与极性分子TFMA之间的静电相互作用对TFMA单体分子在孔道内的吸附和取向有促进作用;b）在受限空间中的聚合物单体分子之间的静电相互作用使其分子间隙更加紧密,同样也对其分子取向有促进作用;c）在这个两种孔洞与聚合物单体分子相对大小不同的MOF中,单体分子和分子链的取向度基本一致,但单体分子在孔径较大的MOF中吸附数量更多。这三个因素的重要影响,为聚合物单体或MOF的选取、对聚合物链取向及双折射性的控制提供理论预测方法。     

Li和Al掺杂的MgO(001)表面负载W_3O_9团簇的构型与电子结构

采用基于第一性原理的分子动力学和量子力学相结合的方法,对W3O9团簇在经Li和Al原子掺杂的MgO(001)表面的负载构型、稳定性以及体系的电子结构进行了系统研究.结果表明,当掺杂发生在表层时,杂质原子的类型对W3O9团簇的负载构型有显著影响.对于缺电子的Li掺杂,负载后W3O9团簇环状构型并不稳定,转化为链状结构;而Al原子的掺杂则使得MgO(001)表面电子富余,此时W3O9团簇存在平躺和垂直两种吸附方式,二者能量稳定性相近,其中前者存在同时与三个W原子成键的帽氧结构.当掺杂发生在次表层时,两种掺杂体系W3O9的负载构型相似,团簇仍保持环状结构并倾向于采用垂直方式沉积在表面上.与Li掺杂体系相比,富电子的Al掺杂可显著增强W3O9与MgO(001)表面之间的结合能力,负载后有较多电子从表面转移到团簇中特定的W原子上,这将对W3O9团簇的催化性能产生显著影响.     

Denting Nanospheres with a Short Peptide

Dented nanospheres show promising potential in drug delivery,nanomotors,etc.However,it is still challenging to prepare them by homopolymer self-assembly because of the strict structural requirements of the homopolymer.Herein,we propose a strategy for preparing dented nanospheres from homopolymers by co-assembly with a short peptide.They were co-assembled from poly(2-hydroxy-3-((4-(ethoxycarbonyl)phenyl)amino)propyl methacrylate) (PHBzoMA59) and (S)-2-((S)-2-((((gH-fluoren-9-yl)methoxy)carbonyl)amino)-3-phenylpro-panamido)-3-phenylpropanoic acid (Fmoc-FF-OH).PHBzoMA homopolymers can only self-assemble into nanospheres without dent,and the addition of a short peptide introduced hydrogen bonding and complementary π-π stacking interactions led to the final dented nanosphere morphology.The weight fractions of the short peptide can be adjusted to regulate the final morphology.It was confirmed that the radius of curvature of the dent on the surface was related to the organic bubble inside the protospheres prepared at critical aggregation concentration(CAC).The organic bubble can be adjusted by altering the kind of organic solvent and solution pH,which allowed control over the dented nanosphere dimension.The use of different organic solvents with various polarities allows adjustment of the interfacial tension,and hence the denting degree.This degree can also be controlled by manipulating the solution pH to (de)protonate the short peptide and homopolymer.Furthermore,the versatility of this method was highlighted by using a different homopolymer and the applicability of the resulting dented nanospheres was demonstrated by decoration with gold nanoparticles.Overall,this study provided important insights and a new simple strategy to prepare dented nanospheres in a controlled fashion.     

Li和Al掺杂的MgO(001)表面负载W3O9团簇的构型与电子结构

采用基于第一性原理的分子动力学和量子力学相结合的方法, 对W₃O₉团簇在经Li 和Al 原子掺杂的MgO(001)表面的负载构型、稳定性以及体系的电子结构进行了系统研究. 结果表明, 当掺杂发生在表层时, 杂质原子的类型对W₃O₉团簇的负载构型有显著影响. 对于缺电子的Li 掺杂, 负载后W₃O₉团簇环状构型并不稳定, 转化为链状结构; 而Al 原子的掺杂则使得MgO(001)表面电子富余, 此时W₃O₉团簇存在平躺和垂直两种吸附方式, 二者能量稳定性相近, 其中前者存在同时与三个W原子成键的帽氧结构. 当掺杂发生在次表层时, 两种掺杂体系W₃O₉的负载构型相似, 团簇仍保持环状结构并倾向于采用垂直方式沉积在表面上. 与Li 掺杂体系相比, 富电子的Al 掺杂可显著增强W₃O₉与MgO(001)表面之间的结合能力, 负载后有较多电子从表面转移到团簇中特定的W原子上, 这将对W₃O₉团簇的催化性能产生显著影响.     

Sample preparation and direct electrospray ionization on a tip column for rapid mass spectrometry analysis of complex samples

A handheld pipette tip column electrospray ionization source (PTC-ESI source) was developed for rapid mass spectrometry analysis at ambient pressure. The PTC-ESI source was made up of three main component parts including a micro DC high voltage (HV) power supply, a micropipette and a disposable micropipette tip filled with a plug of adsorbent. A DC high voltage was applied to the sharp point of the micropipette tip column to induce electrospray ionization. The PTC-ESI source was successfully used for direct analysis of basic organic compounds, organic acids and peptides in a simple matrix. In the case of complex samples, micro-extraction based on the adsorbent phase filled in the pipette tip was used to remove impurities and concentrate target analytes prior to ionization. The eluting solution was not pipetted out, but directly dispersed in the form of electrospray from the pipette tip for ionization. The effectiveness of the PTC-ESI source has been further demonstrated by fast analysis of therapeutic compounds and endogenous bioactive chemicals in complex biological samples.     

Interaction Behaviours Between Solitons and Cnoidal Periodic Waves for (2+1)-Dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada Equation

The consistent tanh expansion (CTE) method is employed to the (2+1)-dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada (CDGKS) equation. The interaction solutions between solitons and the cnoidal periodic waves are explicitly obtained. Concretely, we discuss a special kind of interaction solution in the form of tanh functions and Jacobian elliptic functions in both analytical and graphical ways. The results show that the profiles of the soliton-cnoidal periodic wave interaction solutions can be designed by choosing different values of wave parameters.     

超滤法处理改善小鼠单抗的固定化效果

商品化小鼠单抗试剂中普遍添加了高浓度的保护蛋白,如牛血清白蛋白(BSA),这给抗体的固定化带来了严重的干扰。本研究基于超滤技术发展了一种超微量抗体试剂(用量为10μL,约含2μg抗体、100μgBSA)预处理方法,能有效去除商品化抗体试剂中的高浓度BSA,使微珠表面固定化小鼠单抗的数量显著提高,并在蛋白质检测中得到了较好的结果,为缓解抗体产品供应现状对蛋白质芯片研究工作的制约提供了一条简单实用的途径。