人体内酮体检测技术的研究进展

论述了检测人体内酮体浓度的重要意义和酮体的代谢过程，对各种检测技术的发展过程、检测原理、操作步骤及各自的优缺点进行了比较分析，着重探讨了对血液中β-羟丁酸的检测，并对各种技术的发展方向作了进一步的展望。     

pH‐Triggered Charge‐Reversal Polyurethane Micelles for Controlled Release of Doxorubicin

A series of pH‐triggered charge‐reversal polyurethane copolymers (PS‐PUs) containing methoxyl‐poly(ethylene glycol) (mPEG), carboxylic acid groups, and piperazine groups is presented in this work. The obtained PS‐PUs copolymers can form into stable micelles at pH 7.4, which response to a narrow pH change (5.5–7.5) and show a tunable pH‐triggered charge‐reversal property. Doxorubicin (DOX) is encapsulated into the PS‐PU micelles as a model drug. The drug release of DOX‐loaded PS‐PU micelles shows an obviously stepped‐up with reducing the pH. Meanwhile, it is found that the charge‐reversal property can improve the cellular uptake behavior and intracellular drug release in both HeLa cells and MCF‐7 cells. Additionally, the time‐dependent cytotoxicity of the DOX‐loaded PS‐PU micelles is confirmed by MTT assay. Attributed to the tunable charge‐reversal property through changing the molar ratio of piperazine/carboxyl, the PS‐PU micelles will be a potential candidate as an intelligent drug delivery system in future studies.

     

A Novel C22 Terpenoid from the Cultured Perovskia atriplicifolia

A novel terpenoid, named perovskiaol ( 1 ), was isolated from the cultured Perovskia atriplicifolia. Its structure was elucidated by comprehensive spectroscopic analysis as well as by quantum chemical computation of electronic circular dichroism spectra. Perovskiaol ( 1 ) was a novel C₂₂ terpenoid containing a unique D‐ring simultaneously fused with rings A, B, and C, and encountered in nature for the first time. Cytotoxic bioassay suggested perovskiaol ( 1 ) possessed significant cytotoxic activity inhibiting NB4, A549, and HepG 2 cell lines with IC₅₀ values of 2.35, 1.47, and 0.81 μm , respectively.     

Metal‐Free Reaction of ortho‐Carbonylated Alkynyl‐Substituted Arylaldehydes with Common Amines: Selective Access to Functionalized Isoindolinone and Indenamine Derivatives

Herein we describe a reaction of ortho‐carbonylated alkynyl‐substituted arylaldehydes with common primary amines that can provide functionalized isoindolinone and 3‐hydroxylindenamine products in high yields. Depending on the substituent size of primary amines, two distinct reaction pathways were exploited selectively, that are, an initial aza‐conjugate addition followed by hydrogen transfer to access isoindolinone framework and a unique oxa‐conjugate addition followed by Petasis–Ferrier rearrangement to afford indenamine derivatives. In the presence of Et₃N, the reaction property of small primary amines was changed, proceeding to afford 3‐hydroxylindenamine derivatives efficiently. These products contain interesting substructures that exist in many natural products and bioactive molecules. The reaction features contain the use of transition‐metal‐free catalysts, simple operation, broad substrate scope, and product diversity.     

开放光程扬尘颗粒物浓度测量方法及系统

利用单波长激光通过扬尘空间发生散射消光衰减的特性,设计了开放光程的颗粒物浓度检测方法及系统。该方法利用双峰正态分布模型模拟颗粒物粒径分布,实时计算一定空间范围内的扬尘颗粒物浓度,具有响应速度快、测量动态范围宽的优点,适合浓度高、变化快、空间范围大的扬尘颗粒物浓度测量。通过水溶胶模拟实验与烟尘实验验证了该方法的可行性。实验数据表明,系统量程可达0~400mg/m3,分辨率为0.05mg/m3,响应时间小于1s。     

解析函数的加权代数中的闭理想问题

该文讨论了单位圆盘上解析函数的加权代数犃犘中的闭理想问题,并且利用加权系给出了一个闭理想成为犃犘中的补子空间的判断准则     

金纳米颗粒的有序制备及其光学特性

采用纳米球蚀刻技术在石英衬底上制备了不同高度的金纳米颗粒阵列.通过扫描电子显微镜对其表面形貌进行了观测,表明金纳米颗粒为有序分布的三棱柱结构.通过红外—紫外吸收光谱仪在190—900nm波长范围内对其光吸收特性进行了测量, 并成功观测到了金纳米颗粒表面等离子体振荡效应引起的光吸收峰,结果表明随着金纳米颗粒高度的增加,其吸收峰的位置向短波方向移动(蓝移).同时对金纳米颗粒的光吸收特性进行了基于离散偶极子近似的理论计算,并与实验结果进行了比较. 关键词： 纳米球蚀刻技术 金纳米颗粒 离散偶极子近似     

高温预生长对图形化蓝宝石衬底GaN薄膜质量的提高

在图形化蓝宝石衬底生长低温缓冲层之前,通入少量三甲基镓（TMGa）和大量氨气进行短时间的高温预生长,通过改变TMGa流量制备了4个蓝光LED样品。MOCVD外延生长时使用激光干涉仪实时监测薄膜反射率,外延片使用高分辨率X射线衍射（002）面和（102）面摇摆曲线估算位错密度,并使用光致发光谱表征发光性能,制备成芯片后测试了正向电压和输出光功率。结果表明,高温预生长可促进薄膜的横向外延,使得三维岛状GaN晶粒在较小的薄膜厚度内实现岛间合并,有利于降低位错密度,提高外延薄膜质量,LED芯片的输出光功率的增强幅度达29.1%,而电学性能无恶化迹象;但高温预生长工艺中TMGa的流量应适当控制,过量的TMGa导致GaN晶粒过大,将延长岛间合并时间,降低晶体质量。