Sol–gel preparation of antireflective coatings at 351 nm with different thickness and improved moisture-resistance

Antireflective (AR) coatings at 351 nm with different thickness were designed and prepared by sol–gel process using tetraethylorthosilicate as precursor and ammonia as catalyst. The parameters of these coatings, including film thickness and refractive index, were calculated by optical formula and the coatings were prepared accordingly. Sol dilution method was used to adjust the film thickness. The wavelengths of maximum transmission measured by UV–Vis spectrophotometer, were used to monitor the film thickness. It was found that AR coatings with higher thickness possess better abrasion-resistance. Hydroxyl terminated polydimethylsiloxane (PDMS) was added into pure silica sol to improve both the abrasion-resistance and moisture-resistance of AR coating.     

Laser cleaning of particle and grease contaminations on the surface of optics

In the high power laser facility, surface contaminations on the optics will worsen the laser beam quality and damage the optics. Particle and grease contaminations are two of the usual contaminations on the surface of optics. In this work, the 1064-nm laser induced plasma shockwave cleaning is utilized to remove SiO₂ particle contaminations on the K9 glass surface. The results indicate the removal ratio can reach above 95%. The effects of parameters (particle position, laser gap distance and laser energy) on the cleaning efficiency have been studied in the case of single pulse laser cleaning. In addition, CO₂ laser (10.6 μm) is utilized to remove the dimethylsilicone oil contaminations on the gold-coated K9 glass surface. The results show that CO₂ laser can effectively remove the dimethylsilicone oil by properly controlling the laser parameters. The cleaned area increases with the increased laser power or irradiation time when the other parameters are constant.     

变量扩维-筛选方法优化西洋参的毛细管电泳分析条件

以西洋参干品的70％乙醇溶液回流提取液为模型样品,研究获取西洋参的中药指纹图谱,应用均匀设计法安排实验,使用变量扩维-筛选方法优化其毛细管区带电泳的实验条件,得出了分离度较好的谱图。主要峰的面积与西洋参重量的线性相关系数都大于0．930。     

阻抑动力学荧光分析法测定痕量苯肼

基于苯肼对吡咯红Y与亚硝酸根反应的抑制作用,建立了一种新的测定痕量苯肼的阻抑动力学荧光分析法。该方法的检出限为7.2ng mL,线性范围为8.0～60ng mL。直接用于环境水样中苯肼的测定。     

Preparation of nucleoside-pyridine hybrids and pyridine attached acylureas from an unexpected uracil ring-opening and pyridine ring-forming sequence

Novel pyrimidine nucleoside-3,5-dicyanopyridine hybrids (4) or pyridine attached acylureas (5) were selectively and efficiently prepared from the reaction of 2′-deoxyuridin-5-yl-methylene malononitrile (1), malononitrile (2) and thiophenol (3) or from an unexpected uracil ring-opening and pyridine ring-forming sequence via the reaction of 1 and 3. It is the first time such a sequence has ever been reported.     

Two new monoterpene glycosides from Doellingeria scaber

Two new methane-type monoterpene glycosides were isolated from the roots of Doellingeria scaber.Their structures wereidentified as trans-p-menthane-1α,2β,8-triol 8-O-β-D-(3',6'-diangeloyloxy)-glucopyranoside and trans-p-menthane-1α,2β,8-triol 8-O-β-D-(3'-angeloyloxy,6'-isobutyloxy)-glucopyranoside based on 1D and 2D NMR spectroscopy.     

表面Al膜污染物诱导熔石英表面损伤特性

在熔石英表面人工溅射一层Al膜污染物,分别测试污染前后熔石英基片在355 nm波长激光辐照下的损伤阈值,并采用透射式光热透镜技术、椭偏仪和光学显微镜研究了污染物Al膜的热吸收、厚度以及激光辐照前后熔石英的损伤形貌。用355 nm波长的脉冲激光分别辐照位于污染的熔石英和洁净的熔石英前后表面的损伤点,并用显微镜在线采集损伤增长图样,测试损伤点面积。实验表明:熔石英前表面的金属Al膜污染物导致基片损伤阈值的下降约30%,后表面的污染物导致基片下降约15%,位于熔石英样片后表面损伤点面积随激光辐照次数呈指数增长,而位于前表面的损伤点面积与激光脉冲辐照次数呈线性增长关系;带有污染的熔石英样片的增长因子比洁净的熔石英样片的增长因子高30%。     

The Effect of Ionic Liquids on the CaCO3 Crystal Growth

In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactcred by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.     

Site-specific Deposition of Colloidal Pd Nanoparticles on Self-assembled Microtubules from Biolipid

Lipid microtubules with wound ribbon features were fabricated by self-assembling method, and the deposition patterns of colloidal Pd particles on tubular template were investigated. The result indicates that colloidal Pd nanoparticles are preferentially decorated on the helical markings in the interior and on the exterior of preformed tubule and to the edge of loosely helical ribbons to obtain helical deposition features. The multi-bilayer microstructure of tubules can be marked by fine Pd nanoparticles deposited at the edge of helical ribbon. There are the site-specific interactions between lipid tubular template and colloidal Pd particles at the helical edge. A new route was illustrated that colloidal Pd particles firstly attach at the edge of thin flat membranes, and then thin membranes roll up and reassemble into tubule together with particles to form helical deposition patterns. The site-specific deposition of Pd is unbeneficial to obtain the homogeneous metal film on tubules, but it can be utilized to reveal the different chemical nature of lipid molecular assembly.