Objective measurement of minimal erythema and melanogenic doses using natural and solar-simulated light

Very little information exists on the amount of natural and artificial UV light required to cause sunburn and tanning in individuals with very pale skin who are at the greatest risk of developing skin cancer. We have investigated minimal erythema dose (MED) and minimal melanogenic dose (MMD) in a group of 31 volunteers with Fitzpatrick skin types I and II using an Oriel 1000 W xenon arc solar simulator and natural sunlight in Sydney, Australia. We measured the erythemal and melanogenic responses using conventional visual scoring, a chromameter and an erythema meter. We found that the average MED measured visually using the artificial UV source was 68.7 +/- 3.3 mJ/cm2 (3.4 +/- 0.2 standard erythema doses [SED]), which was significantly different from the MED of sunlight, which was 93.6 +/- 5.6 mJ/cm2 (P < 0.001) (11.7 +/- 0.7 SED). We also found significant correlations between the solar-simulated MED values, the melanin index (erythema meter) and the L* function (chromameter). The average MMD (obtained in 16 volunteers only) using solar-simulated light was 85.6 +/- 4.9 mJ/cm2, which was significantly less than that measured with natural sunlight (118.3 +/- 8.6 mJ/cm2; P < 0.05). We mathematically modeled the data for both the chromameter and the erythema meter to see if we were able to obtain a more objective measure of MED and differentiation between skin types. Using this model, we were able to detect erythemal responses using the erythema index function of the erythema meter and the a* function of the chromameter at lower UV doses than either the standard visual or COLIPA methods.     

Studies of modification of HDPE and interfacial interaction of its composites with sericite

Ultraviolet irradiation, which is environment friendly and without any chemical pollution, was used to functionalize high‐density polyethylene (HDPE) and to improve the interfacial interaction of its composites with sericite in this study. The oxygen‐containing groups of C?O, C‐O, and C(?O)O were quickly introduced onto molecular chains of HDPE by ultraviolet irradiation in ozone atmosphere and the contents of the introduced oxygen‐containing groups increased with increasing the modification time. It is important to note that the irradiation time greatly decreased compared to that in air or oxygen atmosphere. After modification, the molecular weight of the irradiated HDPE decreased and its distribution became wider. The irradiated HDPE in ozone was not crosslinked, which is an advantage over the same reaction in air or oxygen atmosphere. With increasing the irradiation time, the melting temperature of the irradiated HDPE lightly decreased, while its crystallinity, hydrophilicity, and fluidity increased. The composites of HDPE/sericite were prepared. The results showed that the dispersion of sericite in the matrix and the interfacial interaction of sericite with the matrix were markedly improved for the irradiated HDPE/sericite composites. As a result, the irradiated HDPE/sericite composites showed significantly increased tensile yield strength and notched impact strength. Copyright © 2010 John Wiley & Sons, Ltd.     

Identification and determination of effective components in Euphrasia regelii by capillary zone electrophoresis

A capillary zone electrophoresis (CZE) method has been developed for simultaneous determination of eukovoside, cinnamic acid and ferulic acid in Euphrasia regelii for the first time. The electrophoresis buffer was 20 mmol/L sodium borate containing 10% (v/v) methanol (pH 8.50). The effects of concentration of borate and electrolyte pH on electrophoretic behavior and separation were studied. Regression equations revealed linear relationships (correlation coefficients 0.9995-0.9998) between the peak area of each analyte and the concentration. The levels of analytes in the different parts of Euphrasia regelii were easily determined with recoveries ranging from 95.5 to 104.2%.     

压电增强的等离激元光催化材料Ag/BaTiO3的制备及性能研究

针对光催化过程中的低光利用率和低催化效率，采用光化学还原法将Ag纳米颗粒均匀修饰在BaTiO₃纳米压电材料表面，制备了x mol/L-Ag/BaTiO₃（x=0.01、0.02、0.04，x为Ag的浓度）等离激元压电光催化剂.研究了压电光催化过程中的反应机理及等离激元颗粒负载的浓度对光催化剂性能的影响.研究结果显示，0.02 mol/L-Ag/BaTiO₃在全光谱光辐照和超声激发的压电场的辅助下，在75 min内可降解91%的罗丹明B，将降解效率提升了21%，证实了纳米复合结构中压电势对表面等离激元光催化活性的重要影响.催化性能的提升源于压电效应和表面等离子体共振效应的协同作用.Ag纳米颗粒的等离子体共振效应（LSPR），使光吸收范围从紫外光区扩大至可见光波段.超声驱动可使BaTiO₃纳米压电体发生形变而于表面产生压电电荷，压电势的存在进一步增强了LSPR诱导的光生载流子分离，促进羟基自由基的生成，加速有机染料的降解.本工作将BaTiO₃的压电效应引入等离子体光催化中，可推广到其他材料和催化系统中，为环境净化提供一种有效的技术.     

Recent advances in photofunctional polymorphs of molecular materials

Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system.In this review,we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth,their adjustable photofunctional properties and multifunctional applications,which will help to illustrate the structure-property relationship.     

HIRFL-CSR外靶装置上的放射性束实验数据分析方法研究

开发了HIRFL-CSR外靶实验装置的大型数据分析程序(ANAETF),并成功应用于核物理实验数据分析。详细阐述了该程序中的数据分析流程、漂移室寻迹算法、粒子鉴别方法和反应截面提取技术。利用本程序分析了240 MeV/u能量下12C次级束流打碳靶的实验数据,实现了清楚的碳和硼剩余核的粒子鉴别,总探测效率达到 ~90%,本工作提取的反应截面与已有的实验结果符合较好。     

Rapid and sensitive determination of anthraquinones in Chinese herb using 1-butyl-3-methylimidazolium-based ionic liquid with beta-cyclodextrin as modifier in capillary zone electrophoresis

The present study reported the ionic liquid (IL) used as running electrolyte in capillary zone electrophoresis (CZE) with beta-cyclodextrin (beta-CD) as modifier for the separation of anthraquinones extract of Chinese herb Paedicalyx attopevensis Pierre ex Pitard. The optimum running electrolyte was 60 mM 1-butyl-3-methylimizolium tetrafluoroborate (1B-3MI-TFB) solution with 4.0 mM beta-CD. The pH was 10.00 and the applied voltage was 20 kV with detection at 254 nm. The present method was compared with others and the effect of Joule heating was discussed as well. More significantly, this method is the development of the ionic liquids application to the capillary electrophoresis.     

CE with Field-Enhanced Stacking for Rapid and Sensitive Determination of Umbelliferone, Rutin and Aesculetin in Prunella vulgaris

A new capillary electrophoresis procedure with field-enhanced stacking concentration for the analysis of umbelliferone, rutin and aesculetin in Prunella vulgaris is established for the first time. After optimization of the separation and concentration conditions, the three analytes can be separated within 6 min and quantified with high sensitivity. The method was useful for qualitative and quantitative analysis of umbelliferone, rutin and aesculetin in Prunella vulgaris with recovery of 97.5 to 105.3%.     

Algorithm for in vitro Sun Protection Factor based on transmission spectrum measurement with concomitant evaluation of photostability

In the in vitro evaluation of Sun Protection Factor (SPF), the photostability of the ultraviolet (UV) filters can have a major impact, especially for high-SPF formulations, but is generally not taken into consideration. In this study, we present a UV transmission spectrum measurement system utilizing a high-sensitivity UV photomultiplier tube with concomitant evaluation of photostability. We have developed an algorithm to estimate SPF in vitro by converting the amount of UV light transmission through the sunscreen layer into cumulative relative erythema effectiveness to obtain one minimal erythema dose. Thus, the algorithm uses the same endpoint as in vivo SPF methods, but with a photomultiplier tube as the detector instead of skin. The values obtained showed an excellent correlation with in vivo SPF values, even for high-SPF sunscreens exceeding SPF 50. This method should be suitable as an in vitro SPF testing method for regulatory purposes.     

Characterization of the materials used in Chinese ink sticks by pyrolysis-gas chromatography–mass spectrometry

Chinese ink stick has a long history and a special importance in Chinese culture. Its main components are soot (normally pine wood soot and lamp soot) and animal glue; however, additives were added from time to time for different purposes. In order to see whether the two types of soot can be differentiated and the other constituents in Chinese ink sticks can be identified or not by Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS) and GC-MS techniques, an initial study has been carried out. The main polycyclic aromatic hydrocarbons (PAHs) in soot could be identified, which are anthracene, fluoranthene, triphenylene and benz[e]acephenanthrylene. The main difference between those two types of soot is that the detectable amount of PAHs in lamp soot is much lower than in pine wood soot. In addition to this, the relative concentration of the main polycyclic aromatic hydrocarbons including anthracene, fluoranthene, pyrene, triphenylene and its isomer, benzo[k]fluoranthene and its isomers are different in the two types of soot. The relative content of benzo[k]fluoranthene is higher in pine soot than in lamp soot, which could be used to as a criterion to differentiate the two types of soot. Py-GC-MS technique is a very effective method to identify the main components of Chinese ink sticks, including the PAHs of soot, binding media and the additives of camphor and borneol in one analysis.