基团贡献法估算线性烷基醇分子体系电子相关能

在本文中,提出了极性基团电子相关能贡献的定义,并在MP2-OPT2/6-311++G(d)水平上计算了CH₃(CH₂) _mOH( m=0-4)体系中HO-、CH₃-和-CH₂-基团电子相关能贡献值。计算结果表明,在CH₃(CH₂) _mOH( m=0-4)体系中端基HO-、CH₃-基团电子相关能贡献值 E_corr(HO-)和 E_corr(cH₃-)的数值随着 m的增加而逐渐减小。同一体系中a -CH₂-基团电子相关能贡献值大于其它-CH₂-基团电子相关能贡献值,在CH₃(CH₂) _mOH( m=1-4)体系中,距离端基HO-基团越远的-CH₂-基团其电子相关能贡献值越小;通过计算结果可以推断,在CH₃(CH₂) _mOH体系中随着 m的逐渐增加,相对远离端基HO-的-CH₂-基团的电子相关能贡献值表现出收敛趋向并将趋于不变,此-CH₂-基团可看作一个标准的亚甲基而且其 E_corr(-cH₂-)的数值在CH₃(CH₂) _mOH体系中具有传递性。在MP2-OPT2/6-311++G(d)水平上对CH₃(CH₂) _mOH( m=2-4)体系的计算结果和应用Gaussian 98程序在MP2/6-311++G(d)//HF/6-311++G(d)水平上对CH₃(CH₂) _mOH( m=2-7)体系的计算结果均表明,体系总电子相关能与（ m-1）呈 中 m是体系中亚甲乙烯基的数值。     

1R，3S-1，2，2-三甲基-1，3-环戊二胺为配体的铂(Ⅱ) 配合物的合成、表征和抗肿瘤活性

本文合成了9种含有由天然D(+)-樟脑衍生的1R，3S-1，2，2-三甲基-1，3-环戊二胺(A)为配体的铂(Ⅱ)配合物[Pt(Ⅱ)AX]{其中，X=(CH₂)₃C(COO^-)₂(1，1-环丁烷二羧酸根)，2CH₃OCH₂COO^-，2CH₃CH₂OCH₂COO^-，2CH₃(CH₂)₃OCH₂COO^-，[OCH(CH₃)COO]^2-(乳酸根)，(OCH₂COO)^2-(乙醇酸根)，2CH₃OCH₂CH₂OCH₂COO^-，2CH₃CH₂OCH₂CH₂OCH₂COO^-和2CH₃(CH₂)₃OCH₂CH₂OCH₂COO^-}。通过元素分析、热重分析、红外光谱、¹H核磁共振谱和电喷雾质谱等对配合物进行了表征。体外生物活性测试表明，部分配合物对A549人肺癌细胞和HCT-116人结肠癌细胞具有较强的抗肿瘤活性。     

Gemini表面活性剂与DNA在气/液界面上的相互作用

在气/液界面上, 阳离子表面活性剂可以通过静电作用与阴离子型的脱氧核糖核酸(DNA)分子形成复合膜, 并压缩沉积得到LB(Langmuir-Blodget)膜. 利用表面压-表面积(π-A)曲线、原子力显微镜(AFM)和石英晶体微天平(QCM)研究了阳离子Gemini表面活性剂([C₁₈H₃₇(CH₃)₂N⁺-(CH₂)_s-N⁺(CH₃)₂C₁₈H₃₇]·2Br^-, 简写为18-s-18, s=3, 4, 6, 8, 10, 12)与DNA(双链DNA(dsDNA), 单链DNA(ssDNA))之间的相互作用, 并对18-s-18在不同下相表面的分子面积进行了比较. 实验结果表明连接基团和下相的DNA对Gemini表面活性剂在气/液界面上的性质有很大影响. 此外, Gemini表面活性剂在界面上对DNA的吸附能力与它们之间的相互作用方式密切相关.     

两个丁二肟有机锡配合物的合成、结构及抗癌活性

合成了 2 个丁二酮肟有机锡化合物:双(三(2-甲基-2-苯基丙基)锡)丁二酮肟配合物(C₆H₅C(CH₃)₂CH₂)₃Sn(ON=C(CH₃)C(CH₃)=NO)Sn(CH₂C(CH₃)₂C₆H₅)3 (1)和二苄基锡氧氯丁二酮肟多核配合物[μ₃-O-((C₆H₅CH₂)₂Sn)₂(ON=C(CH₃)C(CH₃)=NOH)(O)Cl]₂(2)。通过元素分析、红外光谱、核磁共振(¹H、¹³C、¹¹⁹Sn)、差热分析和单晶 X射线衍射对配合物进行了结构表征, 对其结构进行量子化学从头计算, 并进行了体外抗癌活性研究。结果显示:配合物 1为通过配体丁二酮肟桥联的双锡核中心对称分子, 锡原子均为四配位的畸变四面体构型; 配合物 2 为通过氧原子和丁二酮肟配体桥联的四锡核中心对称多环聚合结构, 锡原子分别为五配位的畸变三角双锥构型和六配位的畸变八面体构型。配合物对人肝癌细胞(HUH7)、人肺癌细胞(A549)、人表皮癌细胞(A431)、人结肠癌细胞(HCT-116)和人乳腺癌细胞(MDA-MB-231)均有较强的抑制活性。     

模板剂在分子筛合成过程中的作用机理

启用分子模拟途径,通过Lennard-Jones势对模板剂分子与分子筛骨架间非成键作用的能学分析,论证n=5、6的双季铵盐［(CH₃)₃N(CH₂)_nN(CH₃)₃］Br₂在ZSM-50分子筛骨架合成过程中所起的模板作用。     

含砜功能基的交联聚苯乙烯的红外光谱特性

 本文合成了一系列聚苯乙烯基支载的含砜基的化合物X=Cl,O(CH₂)₉CH₃,NH₂,NHNH₂,Na,CH₂CH₃,OH)并较系统地研究了这些聚合物中的=SO₂基团的红外光谱特性,比较了聚合物和低分子类似物的特征吸收频率的变化规律,考察了聚合物骨架对S=O基团的虹外吸收峰的影响。     

膦配体取代的乙基乙撑双铁配合物的合成、晶体结构及电化学催化性能

以母体配合物[Fe₂(CO)₆(μ-SCH₂CH(CH₂CH₃)S)](1)分别与三(2-呋喃基)膦、二苯基丙基膦、双(二苯基膦)乙炔、1,2-双(二苯基膦基)苯和脱羰试剂Me₃NO·2H₂O反应,制备了单取代配合物[Fe₂(CO)₅(L)(μ-SCH₂CH(CH₂CH₃)S)](L=P(2-C₄H₃O)₃,2;Ph₂PCH₂CH₂CH₃,3)、桥联配合物{[Fe₂(CO)₅(μ-SCH₂CH(CH₂CH₃)S)]2(Ph₂PC≡CPPh₂)}(4)和螯合配合物[Fe₂(CO)₄(κ²-(Ph₂P)₂(1,2-C₆H₄))(μ-SCH₂CH(CH₂CH₃)S)](5)。配合物2~5经元素分析、红外光谱、核磁共振氢谱和磷谱表征,并进一步得到单晶X射线衍射的确证。电化学研究表明,在弱酸HOAc作为质子源存在的情况下,这些配合物可以实现催化质子还原产生氢气的功能。     

富勒烯配合物C60Pd(Ph2PCH2CH2CH2CH2PPh2)的合成和光电性能

本文在惰性气氛中通过取代反应合成出富勒烯金属配合物C₆₀Pd(Ph₂PCH₂CH₂CH₂CH₂PPh₂)，采用元素分析、红外光谱、紫外可见光谱、光电子能谱以及X射线粉末衍射等手段对产物进行表征,同时研究了产物的氧化还原性能及热稳定性能。此外，在光电化学电池中测定了C₆₀Pd(Ph₂PCH₂CH₂CH₂CH₂PPh₂)在GaAs电极上形成n+n型异质结的光伏效应，结果表明：产物具有优良的光电转化性能，尤其是在BQ/H2Q介质电对中，光生电压最大达到212 mV；当C₆₀Pd(Ph₂PCH₂CH₂CH₂CH₂PPh₂)薄膜厚度为1 μm时，光伏效应值最大。     

膦配体取代的乙基乙撑双铁配合物的合成、晶体结构及电化学催化性能

以母体配合物[Fe₂(CO)₆(μ-SCH₂CH (CH₂CH₃) S)](1)分别与三(2-呋喃基)膦、二苯基丙基膦、双(二苯基膦)乙炔、1,2-双(二苯基膦基)苯和脱羰试剂Me₃NO · 2H₂O反应,制备了单取代配合物[Fe₂(CO)₅(L)(μ-SCH₂CH (CH₂CH₃) S](L=P (2-C₄H₃O)₃,2;Ph₂PCH₂CH₂CH₃,3)、桥联配合物{[Fe₂(CO)₅(μ-SCH₂CH (CH₂CH₃) S)]₂(Ph₂PC≡CPPh₂)}(4)和螯合配合物[Fe₂(CO)₄(κ₂-(Ph₂P)₂(1,2-C₆H₄))(μ-SCH₂CH (CH₂CH₃) S)](5)。配合物2~5经元素分析、红外光谱、核磁共振氢谱和磷谱表征,并进一步得到单晶X射线衍射的确证。电化学研究表明,在弱酸HOAc作为质子源存在的情况下,这些配合物可以实现催化质子还原产生氢气的功能。     

三齿NS2型配体Cu(Ⅱ)配合物的合成、光谱性质及电化学性质

A variety of complexes Cu(NS₂)(Im)(NO₃)₂ and Cu(NS₂)(Py)(NO₃)₂ where NS₂=HN(CH₂CH₂SR)₂(R=CH₃CH₂CH₂, (CH₃)₂CH,CH₃CH₂CH₂CH₂ and (CH₃)₂CHCH₂), have been synthesized and characterized by elementary analyses, molar conductivity, IR, UV/Vis and ESR spectra as well as by electrochemical methods. The new complexes exhibit exceptionally high redox potentials(500～580 mV) and complexes for HN(CH₂CH₂SCH(CH₃)₂)₂ exihibit rather hyperfine splitting constants(a_‖<70G) in the powder ESR spectra, which are close to those for the blue copper proteins.     

Preferential adsorption of amino-terminated silane in a binary mixed self-assembled monolayer

The composition and structure of a binary mixed self-assembled monolayer (SAM) of 3-aminopropyltriethoxysilane (APS, NH(2)(CH(2))(3)Si(OCH(2)CH(3))(3)) and octadecyltrimethoxysilane (ODS, CH(3)(CH(2))(17)Si(OCH(3))(3)) on a silicon oxide surface have been characterized by water contact-angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and sum frequency generation (SFG) vibrational spectroscopy. XPS demonstrated that APS in the mixed SAM is significantly enriched in comparison to that in solution, indicating the preferential adsorption of APS during the SAM formation. AFM observations showed that the mixed SAM becomes rougher. SFG revealed that the coadsorption of APS induced a conformation disordering in the ODS molecules present in the mixed SAM. The surface enrichment of APS has been explained in terms of differences in the surface adsorption rates of the two components as well as in the self-congregation states of APS molecules in the bulk solution. Furthermore, the structure of the water molecules on the mixed SAM surface in contact with the aqueous solutions at different pH's has also been studied. The results indicate that the mixed-SAM modified surface is positively charged at pH < 5 and negatively charged at pH > 7.     

Semicarbazide-functionalized Si(111) surfaces for the site-specific immobilization of peptides

The covalent attachment of semicarbazide-functionalized layers to hydrogen-terminated Si(111) surfaces is reported. The surface modification, based on the photoinduced hydrosilylation of a Si(111) surface with protected semicarbazide-functionalized alkenes, was investigated by means of X-ray photoelectron spectroscopy (XPS), contact angle measurements, and atomic force microscopy (AFM). The removal of the protecting group yielded a semicarbazide-terminated monolayer which was reacted with peptides bearing a glyoxylyl group for site-specific alpha-oxo semicarbazone ligation.     

溶胶-凝胶-水热晶化法制备锐钛矿TiO2纳米膜的耐蚀性能

以钛酸正丁酯为前驱体, 采用溶胶-凝胶-水热晶化法在不锈钢(SS)表面制备TiO₂纳米膜. 利用X射线衍射(XRD)、Raman光谱、场发射扫描电子显微镜(SEM)、原子力显微镜(AFM)和俄歇电子能谱(AES)表征了TiO₂纳米膜的晶型、表面形貌和表面化学组成. 通过极化曲线和电化学阻抗谱(EIS)研究了TiO₂纳米膜的耐蚀性能. 170 °C下水热晶化制备的锐钛矿TiO₂与450 °C焙烧制备的锐钛矿TiO₂的结晶度类似, 但两种TiO₂薄膜的表面结构存在明显差异, 水热晶化法制备的TiO₂纳米膜在3.5% (w) NaCl溶液中的耐蚀性能优于焙烧法制备的.     

硅电极/溶液界面开路电位-时间谱和原子力显微镜在化学镀Ag中的应用研究

用开路电位-时间谱技术,表征了在硅（100）表面化学镀银的硅电极/溶液界 面吸附态。所得结果与原子力显微镜在纳米尺寸上的面结构信息分析结果作了对比 。同时也将该结果与循环伏安法（CV）结果作了比较。证明当硅电极表面具有单层 吸附Ag~+离子、表面单层吸附Ag~+离子发生沉积反应、Ag~+离子发生本体沉积时的 开路电位-时间曲线有完全不同的特征。     

Preparation of End Grafted Polyacrylonitrile Brushes through Surface Confined Radical Chain Transfer Reaction

End grafted polyacrylonitrile (PAN) brush was prepared through surface initiated polymerization via the chain transfer process.The thiol-terminated monolayer and PAN brushes were characterized by FTIR,X-ray photoelectron spectroscopy(XPS),atomic force microscopy (AFM),ellipsometry and contact angle measurements etc.It is demonstrated that radical chain transfer reaction and surface initiated precipitate polymerization can used to prepare end-grafted polymer brushes.     

Metal core bonding motifs of monodisperse icosahedral Au13 and larger Au monolayer-protected clusters as revealed by X-ray absorption spectroscopy and transmission electron microscopy

The atomic metal core structures of the subnanometer clusters Au13[PPh3]4[S(CH2)11CH3]2Cl2 (1) and Au13[PPh3]4[S(CH2)11CH3]4 (2) were characterized using advanced methods of electron microscopy and X-ray absorption spectroscopy. The number of gold atoms in the cores of these two clusters was determined quantitatively using high-angle annular dark field scanning transmission electron microscopy. Multiple-scattering-path analyses of extended X-ray absorption fine structure (EXAFS) spectra suggest that the Au metal cores of each of these complexes adopt an icosahedral structure with a relaxation of the icosahedral strain. Data from microscopy and spectroscopy studies extended to larger thiolate-protected gold clusters showing a broader distribution in nanoparticle core sizes (183 +/- 116 Au atoms) reveal a bulklike fcc structure. These results further support a model for the monolayer-protected clusters (MPCs) in which the thiolate ligands bond preferentially at 3-fold atomic sites on the nanoparticle surface, establishing an average composition for the MPC of Au180[S(CH2)11CH3]40. Results from EXAFS measurements of a gold(I) dodecanethiolate polymer are presented that offer an alternative explanation for observations in previous reports that were interpreted as indicating Au MPC structures consisting of a Au core, Au2S shell, and thiolate monolayer.     

Preparation of a well-defined amino-terminated self-assembled monolayer and copper microlines on a polyimide substrate covered with an oxide nanoskin

A well-ordered, uniform amino (NH(2))-terminated organosilane self-assembled monolayer (SAM) was prepared on a polyimide (PI) substrate, the surface of which had silica-like reactivity. First, through chemical vapor deposition of 1,3,5,7-tetramethylcyclotetrasiloxane and subsequent photooxidation using 172 nm vacuum ultraviolet light, an extremely thin silicon dioxide (SiO(2)) layer about 1 nm thick, which we call an "oxide nanoskin" (ONS), was prepared on a PI substrate. Due to the presence of this ONS layer, the PI surface's properties became almost identical with those of Si covered with native oxide (SiO(2)/Si) without any marked change in surface morphology, as evidenced by zeta-potential measurements, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Next, this ONS-covered PI (ONS/PI) surface was exposed to vapor of a 12.5 vol % solution of N-(6-aminohexyl)(3-aminopropyl)trimethoxysilane (AHAPS) molecules diluted with absolute toluene. On the basis of contact angle analysis, the surface energy of this AHAPS/ONS/PI sample was mostly consistent with that of a SiO(2)/Si substrate covered with an AHAPS-SAM (AHAPS/SiO(2)/Si). On the other hand, the surface energy of an AHAPS-treated PI (AHAPS/PI) substrate was much smaller than that of the AHAPS/ONS/PI substrate due to insufficient surface coverage by the AHAPS molecules. This was also confirmed by lateral force microscopy using photolithographically micropatterned samples. Fabricated micropatterns composed of AHAPS- and SiO(2)-covered regions were clearly imaged on the AHAPS/ONS/PI substrate through their difference in friction, while the friction contrast of the micropatterned AHAPS/PI substrate was unclear. This marked difference in packing density of the AHAPS molecules had a direct influence on the adsorption behavior of palladium colloids and subsequent electroless plating of copper (Cu). As confirmed by AFM and XPS, metallization proceeded only on the AHAPS-covered regions, while the SiO(2)-covered regions remained free of deposits, resulting in the formation of 10-mum-wide Cu microlines on both samples. However, the plating rate achieved on the AHAPS/ONS/PI substrate was about 4.5 times faster than that on the AHAPS/PI substrate and the pattern resolution was considerably fine.     

Tailor-made functionalization of silicon nitride surfaces

This communication presents the first functionalization of a hydrogen-terminated silicon-rich silicon nitride (Si3Nx) surface with a well-defined, covalently attached organic monolayer. Properties of the resulting monolayers are monitored by measurement of the static water contact angle, X-ray photoelectron spectroscopy (XPS), and infrared reflection absorption spectroscopy (IRRAS). Further functionalization was performed by reaction of Si3Nx with a trifluoroethanol ester alkene (CH2=CH-(CH2)8CO2CH2CF3) followed by basic hydrolysis to afford the corresponding carboxylic acid-terminated monolayer with hydrophilic properties. These results show that Si3Nx can be functionalized with a tailor-made organic monolayer, has highly tunable wetting properties, and displays significant potential for further functionalization.     

Formation of alkanethiol monolayer on Ge(111).

Alkanethiols, CH3(CH2)(n-1)SH, are shown to react readily with HF-treated Ge(111) surface at room temperature to form a high-quality monolayer. The resulting films are characterized by using contact angle analysis (CAA), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), spectroscopic ellipsometry (SE), and high-resolution electron energy loss spectroscopy (HREELS). The octanethiol and octadecanethiol films on Ge(111) both exhibit 101 degrees and 40 degrees water and hexadecane contact angles, respectively. These values indicate that the thiol surface coverage is relatively high, and that the films possess a high degree of orientational ordering. The angle-resolved XPS analysis supports that thiols are bound to the Ge surface by Ge-S bonds at the monolayer/Ge interface. The film thickness values obtained by XPS and SE agree well with the earlier reported values on alkyl monolayers on Ge(111) prepared by Grignard reaction. On the basis of HREEL spectra taken after thermal annealing steps, the monolayers are found to be thermally stable up to 450 K. The thermal stability provides further evidence that thiols are covalently bonded to Ge(111).