In Vitro and In Vivo Removal Efficacies of a Formulated Pumpkin Seed Oil Makeup Remover

Pumpkin seed oil is well known for its health benefits due to its high content of fatty acid constituents and tocopherols. The removal efficacy of pumpkin seed oil was assessed using UV–Vis spectroscopy. The oil was able to remove 79.92 ± 0.07%, 41.02 ± 0.25%, and 23.54 ± 0.19% of foundation and liquid and pen eyeliners. A stable makeup remover was formulated using 5–15% pumpkin seed oil. Addition of pumpkin seed oil significantly (P < 0.001) enhanced removal ability of the base remover. The remover containing 5% pumpkin seed oil was able to remove 89.27 ± 0.02%, 67.72 ± 0.08%, and 41.25 ± 0.07% of foundation, liquid, and pen eyeliners, respectively, while those of the remover containing 10% pumpkin seed oil were 78.24 ± 0.02%, 66.88 ± 0.05%, and 38.43 ± 0.05%, and those of the remover containing 15% pumpkin seed oil were 84.41 ± 0.01%, 69.79 ± 0.12%, and 41.88 ± 0.04%, respectively. On the other hand, removal efficiencies of the benchmark were 91.20 ± 0.03%, 73.46 ± 0.10%, and 54.00 ± 0.07%, respectively. The removers containing pumpkin seed oil did not cause skin irritation as monitored by a single closed-patch test in 10 female volunteers. The remover containing 5% pumpkin seed oil was further preference studied in 25 female volunteers in a comparison with the benchmark. The pumpkin seed oil remover gained a better overall preference over the benchmark (82.29 ± 4.17% and 80.20 ± 8.64%; P = 0.287). Of which, skin hydration of the developed bio-oil remover was significantly (P < 0.001) satisfied.     

In situ and real-time optical investigation of nitrogen plasma treatment of polycarbonate

Polycarbonates are very attractive polymeric materials with extensive applications in optical technology as well as for replacing conventional rigid substrates, such as glass. The use of plasma treatments has been successfully employed for improving their surface properties and increasing adhesion of subsequent functional coatings. The objective of this study is to employ in situ and real-time Fourier transform infrared spectroscopic ellipsometry for a detailed investigation of the effect of nitrogen plasma treatment using a pulsed DC voltage, on the optical properties of polycarbonates. Measurements taken before, during and after plasma treatment showed the formation of a surface overlayer in which macromolecular chain scission takes place. The evolution of the overlayer thickness and its bonding has been investigated in detail. Also, the study of the surface nano-topography of polycarbonates by atomic force microscopy showed that plasma treatment increases the surface roughness.     

Key factors to improve the efficiency of roll-to-roll printed organic photovoltaics

In order to achieve the cost-efficient scalability of flexible organic photovoltaics (OPVs), the optimization of key factors related to the materials and roll-to-roll (R2R) processes is necessary. The limited drying during the R2R printing process induces a vertical phase separation leading to the formation of a P3HT-rich top region on the photoactive layer which acts as an electron barrier in normal geometry. We show that the increase of R2R drying time and/or post-annealing can enhance the OPV efficiency by the diffusion of PCBM towards the photoactive layer surface forming an electron transport network. It is estimated that the volume fraction of PCBM at the top region of the films triples from about 9% to 30%. In addition, the direct exposure of PEDOT:PSS to air after printing leads to morphological changes that negatively affect the efficiency. Therefore, the protection of PEDOT:PSS from air in combination to the increase of the R2R drying time enables the significant increase of the R2R printed OPVs efficiency to 1%.     

Self-Assembled Monolayers of Vinyltriethoxysilane and Vinyltrichlorosilane Deposited on Silicon Dioxide Surfaces

Abstract

This study was aimed at deposition of self-assembled monolayers (SAMs) using vinyltriethoxysilane (VTES) and vinyltrichlorosilane (VTCS) molecules chemisorbed on silicon dioxide surfaces. The kinetics of SAM formation on planar glass substrates and silicon wafers was characterized by contact angle measurements. The surface free energy and its dispersion and polar components enabled to estimate the time of immersion required to deposit compact SAMs. Adsorption of organosilane molecules as a function of immersion time was characterized by X-ray photoelectron spectroscopy. The SAM thickness was evaluated by spectroscopic ellipsometry. Surface topography of deposited layers was investigated by atomic force microscopy (AFM). The VTCS/glass combination exhibited the fastest kinetics but the deposit was not uniform and included local agglomerates. The hydrophobic vinyl groups at deposit surface resulted in a surface free energy of 32 mJ/m².     

近红外透射光谱技术快速测定烟用香精理化指标

应用近红外透射光谱分析技术,建立了烟用香精相对密度、折光指数、酸值的近红外预测模型,并对光谱预处理方法进行讨论。将模型的预测结果与标准方法测定结果进行比较,在显著性水平为5%的条件下,两种方法不存在显著性差异。该方法操作简便,可快速、准确地用于烟用香精理化指标的检测。     

光谱法研究壳聚糖铜与人血清白蛋白的相互作用

通过热回流制备了壳聚糖-铜(CTS-Cu)配合物,采用荧光、红外、紫外光谱对配合物CTS-Cu与HSA的相互作用进行了表征,结果表明:在280nm处出现紫外吸收峰,在340nm处使HSA的内源荧光发生猝灭,猝灭速率常数kq=3.014×1014L/mol·s,猝灭类型为静态猝灭,说明CTS-Cu与HSA发生了较强烈的相互作用,形成了基态复合物,其结合常数Ka=4.27×106L/mol。通过加入位点标记物布洛芬(Ibuprofen)和华法林(Warfarin)用荧光法研究了CTS-Cu与HSA的结合位点,表明Warfarin与CTSCu竞争HSA的同一个位点,即SiteⅠ位。采用微量热法研究了CTS-Cu与核桃内生菌的相互作用,随着CTS-Cu浓度的增加,最大产热效率出现的时间逐渐延长,表明CTS-Cu对核桃内生菌的生长有一定的抑制作用。     

X荧光能谱技术鉴别淡水珍珠和海水珍珠的应用

采用X荧光能谱技术研究珍珠中微量元素的种类及其质量分数,以达到无损鉴别淡水珍珠和海水珍珠的目的。利用X射线荧光能谱仪优选适合的激发工作条件,通过设定相同的工作条件,获得珍珠主量元素和微量元素的能量色散图谱,定性分析其主量元素和微量元素的组合关系。其中,Mn的特征峰与Sr/Ca计数比率对鉴别珍珠品种有重要的指示意义。研究表明,在电压为30～35kV、电流为0.50～0.80mA、滤光片PdThick的测试条件下,淡水珍珠一般具有Ca+Sr+Mn的组合关系,海水珍珠具有Ca+Sr的组合关系;淡水珍珠中的Sr/Ca介于0.14～0.37,海水珍珠中的Sr/Ca介于0.46～0.71。综合利用元素的组合关系和Sr/Ca计数比率,可快捷、无损地鉴别珍珠品种。