High‐performance liquid chromatography of some natural dyes: analysis of plant extracts and dyed textiles

In this study, wool fibre samples were mordanted by means of 25% alum mordant solution. The mordanted wool samples were dyed in 50%Reseda luteola L. (weld), 20%Rhamnus petiolaris Boiss (buckthorn) and 50%Datisca cannabina L. (bastard hemp) dyebaths. A reverse‐phase high‐performance liquid chromatography with diode‐array detection method was utilised for the identification of dyes in the dyed wool samples and the plant extracts. The extraction of dyes was carried out with a hydrogen chloride/methanol/water (2:1:1; v/v/v) mixture.     

Modelling of bacterial growth with shifts in temperature using automated methods with Listeria monocytogenes and Pseudomonas aeruginosa as examples

Time to detection (TTD) measurements using turbidometry allow a straightforward method for the measurement of bacterial growth rates under isothermal conditions. Growth rate measurements were carried out for Listeria monocytogenes at 25, 30 and 37°C and for Pseudomonas aeruginosa over the temperature range 25 to 45°C. The classical three-parameter logistic model was rearranged to provide the theoretical foundation for the observed TTD. A model was subsequently developed for the analysis of TTD data from non-isothermal studies based on the Malthusian approximation of the logistic model. The model was able to predict the TTD for cultures of L. monocytogenes or P. aeruginosa undergoing simple temperature shunts (e.g. 25 to 37°C and vice versa), and for a multiple temperature shunt for L. monocytogenes (25-37-25-37°C and 37-25-37-25°C) over a period of 24h. In no case did a temperature shunt induce a lag.     

Preparation and characterization of photocured thiol‐ene hydrogel: Adsorption of Au(III) ions from aqueous solutions

In this study, photocured a novel thiol‐ene hydrogels based on P(Penta3MP4/PEG‐DA/HEMA) were investigated for adsorption of Au(III) ions from aqueous solutions purposes. The photopolymerization kinetics of thiol‐ene‐based formulations was investigated by real‐time infrared spectroscopy. The chemical composition and surface morphology of hydrogels were also characterized. The effect of different parameters on Au(III) adsorption efficiency was examined in detail. Better adsorption behavior was achieved for Au(III) by P(Penta3MP4/PEG‐DA/HEMA) F1 hydrogels. The maximum uptake for Au(III) was at pH 0.5. Both Langmuir and Freundlich adsorption isotherm models were applied and the reusability of thiol‐ene hydrogels investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

分层集输与处理技术在学一联合站设计中的应用

多层系开发的油田,由于采出水水型不配伍,合层集输容易导致管道、设备结垢,针对长庆油田学一联合站多层系开发地面建设的需要,首次采用分层集输、分层处理的双流程工艺,有效地解决了地面集输问题。文章还介绍了学一联合站采用的三相分离脱水、自控等先进技术,这些技术的应用,进一步降低了地面建设的投资。     

吴堡地区南梁油田长4+5油层组沉积微相研究

通过岩石学、岩石相及其组合特征分析,确定了吴堡地区南梁油田延长组长4+5油层组主要发育三角洲前缘亚相沉积,进一步可细分为水下分流河道、水下分流河道侧翼以及浅湖泥3种微相,并建立了不同微相的岩电响应关系。通过剖面相和平面相研究表明,长4+5油层组发育北东和南西2个方向的物源,于区内中部汇合,其中北东向物源规模较大。     

Blocked isocyanates and isocyanated soybean oil as new chain extenders for unsaturated polyesters

Two different blocked isocyanates, diphenylmethane–bis‐4,4′‐ethyleneurea and diphenylmethane–bis‐4,4′‐carbamoil–ϵ‐caprolactam, and isocyanated soybean oil were used as chain extenders for low‐molecular‐weight unsaturated polyesters. Oligomeric polyesters (molecular weight = 600–700), taken from a manufacturing process in the sixth hour of a 16‐h polyesterification reaction, were reacted with these chain extenders, and the desired chain lengths (molecular weight = 1000–1500) were obtained in a very short time through the reaction of the chain extenders with the polyester end groups. The increase in the molecular weight was monitored with gel permeation chromatography. The obtained polymers were characterized with Fourier transform infrared and ¹H‐NMR and with styrene solubility and gel time measurements. After dilution with styrene, the polyesters were cured with a radical initiator. The thermal and mechanical properties of the cured polyesters were examined with dynamic mechanical analysis and thermogravimetric analysis tests and then compared to those of a commercially available reference unsaturated polyester. The results show that unsaturated polyesters can be chain‐extended with these compounds to shorten the polyesterification time substantially without alterations of the styrene solubility or gel time of the polyesters. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

New alternating copolymers of fluorene and triphenylamine bearing terthiophene and acceptor groups in the side chains: Synthesis and photovoltaic properties

A series of conjugated copolymers (P1 and P2-CN-P4-CN) were prepared, in which two kinds of side chains were designed: one was the repeating units similar to that of P3HT, with the aim to increase the compatible with PC₆₁BM and the hole mobility; another one was the acceptor groups connected with the electron-rich backbone through the conjugated 3,4-ethylenedioxythiophene bridge, in order to broaden the absorption and lower the LUMO level. By controlling the ratios of these two kinds of side chains, the absorption band of the resultant conjugated polymers could be fine-tuned, while their energy levels nearly remained unchanged. As the result, the performance of the corresponding devices increased first, then decreased, indicating that there would be a balance between the different function of these two side chains.     

视频监控中运动目标快速检测方法研究

提出了一种背景差分的改进算法.通过像素灰度值归类与形态学相结合的方法来提高背景重构的效率,进一步提高系统的实时性.实验结果表明,改进的算法能够有效克服光线变化、雨雪天气等环境噪声的干扰,适应高密度运动目标检测场景,进一步提高检测速度和效果.     

一起焊点低应力下蠕变断裂案例的分析及启示

系统介绍了某型号航天器电缆网上的焊点低应力断裂问题的原因、产生过程及机理分析。通过对电连接器结构、装联工艺和断口特征的分析,故障定位为：电连接器的特殊结构形式导致在尾罩处理过程中导线无法留有应力余量,而在安装应力直接作用下导致焊点断裂。同时,指出了本案例的启示意义。