肉豆蔻酸单萜醇酯对布南色林经皮透过的影响

本文以环状单萜醇α-萜品醇、L-薄荷醇及链状单萜醇香叶醇、香茅醇为先导化合物,采用酰氯酯化法合成肉豆蔻酸α-萜品醇酯(TER-C14)、肉豆蔻酸-L-薄荷醇酯(MEN-C14)、肉豆蔻酸香叶醇酯(GER-C14)和肉豆蔻酸香茅醇酯(CIT-C14),并考察单萜醇及其肉豆蔻酯作为促透剂对布南色林(Blo)的促透效果。通过体外经皮渗透实验、体外释放实验和分子模拟技术初步探究单萜醇及其肉豆蔻酯的促透机制。结果显示,当GER-C14或CIT-C14为促透剂时,均有显著的促透效果(P<0.05),并且24h经皮累积透过量是空白组的4.84倍和4.45倍。促透机制为肉豆蔻酸单萜醇酯破坏药物与神经酰胺之间的氢键相互作用,增加脂质迁移率和药物的自由能,从而促进药物的渗透。肉豆蔻酸单萜醇酯有望作为新型促透剂在经皮给药系统中广泛应用。     

表面改性的火焰法碳纳米管/聚苯乙烯复合材料的制备与性能

通过傅立叶变换红外光谱(FT-IR)和热失重分析(TGA)等方法研究了火焰法制备的多壁碳纳米管(F-MWCNT)的结构,发现F-MWCNT表面带有一定量的羧基等活性基团.将F-MWCNT直接与氯化亚砜及十六烷基胺反应,成功制备了其酰胺功能化产物(H-MWCNT).扫描电子显微镜(SEM)和动态力学分析(DMA)结果表明,F-MWCNT及酰胺化产物H-MWCNT明显改善了相应的聚苯乙烯(PS)/碳纳米管复合材料的界面结构和力学性能.     

Travel Time Tomography

We survey some results on travel time tomography. The question is whether we can determine the anisotropic index of refraction of a medium by measuring the travel times of waves going through the medium. This can be recast as geometry problems, the boundary rigidity problem and the lens rigidity problem. The boundary rigidity problem is whether we can determine a Riemannian metric of a compact Riemannian manifold with boundary by measuring the distance function between boundary points. The lens rigidity problem problem is to determine a Riemannian metric of a Riemannian manifold with boundary by measuring for every point and direction of entrance of a geodesic the point of exit and direction of exit and its length. The linearization of these two problems is tensor tomography. The question is whether one can determine a symmetric two-tensor from its integrals along geodesics. We emphasize recent results on boundary and lens rigidity and in tensor tomography in the partial data case, with further applications.     

A Bi-based oxychloride PbBiO2Cl as a novel efficient photocatalyst

A novel visible-light-driven layered photocatalyst of Bi-based PbBiO₂Cl is prepared by solid-state reaction. The optical band gap of PbBiO₂Cl is determined to be 2.45 eV by UV–vis diffuse reflectance spectroscopy. Generally, the photocatalytic activity for degrading methyl orange (MO) over PbBiO₂Cl is higher than that over anatase-type TiO₂ under UV light and visible light illumination. The RuO₂ loading over PbBiO₂Cl leads to an obvious increase in photocatalytic performance. The internal electric fields between [PbBiO₂] and [Cl] slabs are considered to be useful for the efficient separation of electron–hole pairs upon photoexcitation.     

Graphitic-C<Subscript>3</Subscript>N<Subscript>4</Subscript> quantum dots decorated {001}-faceted TiO<Subscript>2</Subscript> nanosheets as a 0D/2D composite with enhanced solar photocatalytic activity

Zero-dimensional (0D)/two-dimensional (2D) heterojunctions have attracted great attention in photocatalysis due to their superior interfacial effects. In this work, 0D g-C₃N₄ quantum dots (CNQDs) were firstly used to modify {001}-faceted 2D TiO₂ nanosheets by a simple solvothermal method. During the controlled growth of TiO₂ nanosheets with exposed reactive {001} facets, the CNQDs can be simultaneously assembled on the surface of TiO₂ nanosheets in a highly dispersive way. The 0D/2D composite containing only 0.5% of CNQDs shows the optimized solar photocatalytic activity for the degradation of rhodamine B and 4-chlorophenol. More importantly, the 0D/2D composite exhibits a better solar photocatalytic activity than the bulk g-C₃N₄/TiO₂ nanosheets composite. This improvement can be ascribed to the close interfacial contact and strong interaction between the highly dispersed CNQDs and the TiO₂ nanosheets, which could lead to efficient separation of the photogenerated electron–hole pairs, provide more catalytic active sites, and enhance the absorption of solar light. The 0D/2D composite also shows good stability for its practical applications.     

多光谱全色分色棱镜的胶合

论述了多光谱全色分色棱镜组的胶合工艺。该棱镜组是由６块非标准角棱镜、１块底板和４块滤色镜共１１个零件所组成。该棱镜组各出射面与入射面之间的角度允差要求≤１０″，各通光面与底板底面之间的垂直度要求⊥≤１０″，棱镜中间还有两处空气隙，空气隙的宽度要求为Ｌ＝０．０５ｍｍ。另外，各棱镜在主光路方向上还有距离（光程）要求，因此该棱镜组的胶合工作成了该项任务加工中一个比较关键的技术。     

鼻咽癌患者治疗过程中头发微量元素的变化

对比了３０名健康人与１００名初诊、三个月后复诊及六个月后复诊的鼻咽癌患者头发中的１１种微量元素的含量。发现病人的锌（Ｚｎ）、铜（Ｃｕ）、锰（Ｍｎ）及钴（Ｃｏ）的含量都比健康人低，而病人的钛（Ｔｉ）及砷（Ａｓ）含量则偏高。但经过三至六个月电疗及化疗之后，这些元素的含量普遍与健康人差异变小，这似乎是成功治疗的一个反映。     

Direct synthesis, characterization of Cu-SBA-15 and its high catalytic activity in hydroxylation of phenol by H2O2

Transition metal copper substituted mesoporous silica (Cu-SBA-15) was synthesized using triblock copolymers surfactant as template agent under acidic condition. The result Cu-SBA-15 was characterized with XRD, ICP-AES, FT-IR and N₂ adsorption–desorption measurements, which prove that Cu(II) was mainly incorporated into the framework of Cu-SBA-15. Its catalytic activity was studied for phenol hydroxylation using H₂O₂ (30%). The substituting element (Cu²⁺) is incorporated into the framework position forming a new type of active site which raises the phenol conversion to 62.4% and the diphenol (the mixture of catechol (CAT) and hydroquinone (HQ)) selectivity to 97%. The Cu-SBA-15 has very high selectivity for catechol (about 71% selectivity), which is completely different from that of the microporous titanium silicalite zeolites (47.1% phenol conversion and about 50% selectivity to CAT under same reaction conditions). The results obtained indicate that the selective oxidation of phenol with H₂O₂ by a radical substitution mechanism.     

Imaging theory of an aplanatic system with a stratified medium based on the method for a vector coherent transfer function

A simple formalism relating image fields to object fields, similar to that of the scalar and paraxial case, is presented for an aplanatic system obeying the sine condition, which shows that the vector plane-wave spectrum of image fields is equal to the product of the vector coherent transfer function due to the x- and y-polarized point electric field source and the scalar spectrum of the corresponding transverse object fields. Utilizing this formula and dyadic Green's function, a rigorous imaging theory of an aplanatic system for the point electric current source through a stratified medium is readily developed.     

Experimental observation of tangent-azimuthal non-spiral optical vortex

Optical vortices have attracted much attention recently due to their novel properties and widening applications. And lots of optical vortices can be obtained though most of them turn on spiral pattern on increasing azimuthal angle. In this paper, one kind of non-spiral optical vortex was proposed whose front phase distribution is tangent function of azimuthal angle. And this kind of optical vortices were also observed experimentally by computer-generated hologram method. It was found that when topological charge is smaller than unit one, vortex beam shape changes considerably on increasing topological charge, from hollow pattern to curve shape. When topological charge is bigger than unit and is times of 0.5, vortex beam turns symmetrical polygonal pattern though there is crack between adjacent sides, and the side number is twice of topological charge.