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Poly(3′,4′‐ethylenedioxy‐2,2′:5′,2″‐terthiophene)/ZnO(poly(TET)/ZnO) composites with the ratio of poly(TET) and nano‐ZnO from 3:1 to 1:3 were synthesized by hand grinding and ball milling methods, respectively. The photocatalytic activities of the composites were examined through the degradation processes of methylene blue (MB) solution under UV light irradiation, and the possible mechanism for the photocatalytic activity enhancement by synergetic effects between nano‐ZnO and poly(TET) was proposed. The results showed that the strong interactions between the poly(TET) and nano‐ZnO occurred in the case of ball milling method. The results also proved that the crystallinity of ZnO was not disturbed in both of methods, and the nano‐ZnO was uniformly distributed in polymer matrix in the case of ball milling method. The comparative studies showed that the addition of the nano‐ZnO could enhance the photocatalytic activities of the composites. The highest degradation efficiency (100%) at 3 h under UV light irradiation occurred in the case of poly(TET)/ZnO(1:1) synthesized by ball milling method. Furthermore, the nanocompsosite displayed higher photocatalytic activity than nano‐ZnO, which was due to the holes (h+) transferring from the valence band of ZnO to the polymer backbone and the adsorption of MB molecules in polymer matrix via π–π conjugation between MB and aromatic regions of the poly(TET). POLYM. COMPOS., 36:1597–1605, 2015. © 2014 Society of Plastics Engineers  相似文献   
3.
The quality changes of refined, bleached and deodorized palm olein (RBDPO) and soybean oil (SBO) and their blends were investigated in this study. The oils were studied during intermittent frying of potato chips at 180PT5C for 5 h per day for 5 consecutive days. The indices used for assessment of changes in quality of the oils were fatty acid composition (FAC), peroxide value (PV), anisidine value (AnV), % free fatty acid (FFA), iodine value (IV), % polar component, polymer content, color, viscosity, smoke point and foaming tendency. The results showed that RBDPO was superior to SBO in frying performance in terms of resistance to oxidation, changes in IV, AnV, foaming tendency, % polar component and polymer content. However, SBO performed better than RBDPO with respect to color, viscosity, FAA content and smoke point. Sensory evaluation showed that potato chips fried in both RBDPO and SBO were equally acceptable by the panelists.  相似文献   
4.
Despite being an area of cancer with highest worldwide incidence, oral cancer yet remains to be widely researched. Studies on computer‐aided analysis of pathological slides of oral cancer contribute a lot to the diagnosis and treatment of the disease. Some researches in this direction have been carried out on oral submucous fibrosis. In this work an approach for analysing abnormality based on textural features present in squamous cell carcinoma histological slides have been considered. Histogram and grey‐level co‐occurrence matrix approaches for extraction of textural features from biopsy images with normal and malignant cells are used here. Further, we have used linear support vector machine classifier for automated diagnosis of the oral cancer, which gives 100% accuracy.  相似文献   
5.
ABSTRACT

An accurate simple model of alternators for power system stability studies has been developed. The model is based on a detailed model [1] the validity of which has been verified earlier. The simplification is achieved by omitting stator and transmission line transients from the detailed model and introducing a compensation for the omission. It has been shown that the compensation has to be included at every time step. Since the order of the model is lower than the detailed one its computational speed is faster and memory requirement is less. The accuracy of the simple model including the compensation has been proved to be outstanding by comparing the results of the model with those obtained from the detailed model  相似文献   
6.
This study examines oral tissue color in Uygur and Han Chinese populations. The color of oral tissues is of great significance in dental field. It remains uncertain whether there is any difference in the color of oral tissues between different nationalities or ethnicities. Little is known about the color of oral tissues in different Chinese populations. The study included 263 Uygur and Han students aged 18–22 years. The color of anterior teeth, vermilion, and attached gingiva in the subjects was measured by spectrophotometry and expressed through the CIELCh system. The t test and ANOVA was used to analyze color difference between groups. Distribution ranges for L (lightness), C (chroma) and h (hue angle) of anterior teeth, vermilion, and attached gingiva in these two ethnicities were obtained. Significant differences in color of oral tissues between Uygur and Han Ethnicities were found out. The Uygur and Han populations have similar spatial distribution ranges for the color of oral tissues, with slight differences that displayed strong regularities, suggesting that the color of oral tissues was associated with race. In addition, there was a trend of decreasing lightness (especially for maxillary anterior teeth), increasing chroma and redder hue from the center of teeth toward the sides in both ethnicities. There were differences in the color of teeth and attached gingiva between sexes in the Uygur and Han populations. The color of the upper vermilion differed significantly from that of the lower vermilion. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010  相似文献   
7.
本文用离子交换法制备K+交换玻璃光波导元件,并在其表面固定纳米级敏感层酞菁铜(CuPc)薄膜,利用光波导气体检测系统对NO2气体进行测试.结果表明,该传感元件常温下对NO2等气体有快速、可逆的响应,并具有重现性好,灵敏度高等特点.  相似文献   
8.
A single capillary model is proposed to predict the increase in pressure drop due to the particle deposition. The model is based on mass balance and trajectory analysis considering physical force (London—Van der Waals), hydrodynamic force (gravity and drag) and electrokinetic force (double layer). The validity of the model was tested experimentally by simulating a micro-capillary of radius 34.37 μm and circulating bentonite suspension at different flow rates and concentrations. The model is valid for predicting the pressure build up due to smooth deposition of particles with minimal surface energy.  相似文献   
9.
A simple and inexpensive circuit for measuring the phase angle difference between two waves with lead/lag indication is described. The proposed circuit may be adopted in the laboratory as an attachment to a commercially available analogue/ digital multimeter to measure the phase difference. The response is linear over a range 0 to + 180° and is unaffected by the input frequencies in the range 6 Hz–1.2 kHz. For distorted waveforms, the paper also gives a simple scheme to measure the displacement angle which in turn suggests its use in a high-power-factor self-compensated alternating voltage controller.  相似文献   
10.
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