季节冻土区挡土墙水平冻胀力设计取值

论述了作用在季节冻土区水工挡土墙结构上的水平冻胀力压强分布图形和设计取值方法，为确定挡土墙结构上的冻胀荷载提供一个实用方法。     

GaAs大面积液相外延载流子均匀性的研究

采用液相外延技术在(100)GaAs衬底上生长无位错外延层,对外延片的载流子均匀性进行了测试和分析。为了改善载流子分布的均匀性,采用了脱氧15h,熔源8h以上,再同一源重复使用、多次生长的液相外延工艺。同时,为了满足实验的需要,设计了一种新型推拉式石墨舟。实验结果表明此方法是可取的。     

Novel Mo-V Oxide Catalysts with Nanospheres as Templates for the Selective Oxidation of Acrolein to Acrylic Acid

Catalysis Letters - Novel Mo-V-PMMA and Mo-V-PS catalysts are prepared by addition of hard polymethyl methacrylate (PMMA) and polystyrene (PS) nanospheres into Mo/V compounds in the preparation...     

Effect of graft copolymer matrix prepared by reversible addition–fragmentation chain transfer and atom transfer radical polymerization on the electro‐optical properties of polymer‐dispersed liquid crystals

A type of graft macroinitiator, synthesized by reversible addition–fragmentation chain transfer (RAFT) and atom transfer radical polymerization, was employed to prepare polymer‐dispersed liquid crystals (PDLCs) with graft copolymer matrix; meanwhile, a linear macroinitiator was also synthesized via RAFT polymerization. The effect of linear and graft macroinitiators on the electro‐optical (EO) properties of the PDLCs was investigated. The results showed that the graft macroinitiator could make a large difference to the EO properties of the PDLCs. The memory effect was reduced remarkably, but the driving voltage increased and transmittance decreased. A possible mechanism is presented. © 2014 Society of Chemical Industry     

The effect of photoinitiator concentration and structures of RAFT macroinitiators on the memory effect of polymer dispersed liquid crystals

The article aimed to decrease the memory effect of polymer dispersed liquid crystals (PDLCs) films, reversible additional‐fragmental chain transfer (RAFT) polymerization was used to synthesize RAFT‐polystyrene (RAFT‐PS), which was a kind of RAFT macroinitiators and used to prepare PDLCs via photo polymerization induced phase separation (PIPS). Different RAFT agents were used to synthesize RAFT‐PS. The effect of photoinitiator concentration on the memory effect of these PDLCs was investigated, and the effect of structures of RAFT macroinitiators on the memory effect of the PDLCs was also discussed. The results showed that PDLC films with higher photoinitiator concentration and polymer matrix which had two rigid chains in two ends showed lower memory effect, which could be reduced from 10.9% to 2.5% in this experiment. POLYM. ENG. SCI., 55:8–13, 2015. © 2014 Society of Plastics Engineers     

The improvement of electro‐optical properties of polymer‐dispersed liquid crystals with graft copolymer matrix synthesized by reversible addition–fragmentation chain transfer and atom transfer radical polymerization

Aiming to decrease the memory effect of polymer‐dispersed liquid crystals (PDLCs), a type of graft macroinitiator, synthesized by reversible addition–fragmentation chain transfer and atom transfer radical polymerization, was employed to prepare PDLCs with graft copolymer matrix in our previous work. Compared with linear copolymer matrix PDLCs prepared using a linear macroinitiator, it was found that, although low‐memory‐effect PDLCs were obtained, the driving voltage and transmittance of the PDLCs were unfortunately sacrificed to some extent. Thus, it is necessary to improve the electro‐optical properties of PDLCs on the basis of the original research performed by us. In the work reported in this article, a kind of linear macroinitiator with high refractive index and another graft macroinitiator with flexible branched chains were employed to prepare PDLCs. The results showed that by using mixed macroinitiators, the electro‐optical properties of PDLCs could be improved, and a possible mechanism is proposed.     

Imidazole/(HPO3)3‐doped sulfonated poly (ether ether ketone) composite membrane for fuel cells

A novel gel of imidazole/(HPO₃)₃ was synthesized and incorporated into sulfonated poly (ether ether ketone) (SPEEK) to fabricate composite proton exchange membranes. The composite membranes were characterized by alternating current impedance (AC), thermogravimetry (TG), differential scanning calorimetry (DSC), X‐ray diffraction (XRD), scanning electron microscope (SEM) and mechanical property test. Based on the electrochemical performance investigation, the proton conductivity of the membrane is intimately correlated with the temperature and the mass ratio of imidazole/(HPO₃)₃ in the composite. The SPEEK/imidazole/(HPO₃)₃?4 composite membrane (with 44.4 wt % of imidazole/(HPO₃)₃) has the optimized performance at 135°C. Mover, the strength of the composite membranes is almost comparable to that of Nafion membrane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41946.     

纳米无机阻燃剂及其阻燃机理研究进展

介绍了纳米三氧化二锑(Sb2O3)、纳米氢氧化铝[Al(OH)3]、纳米氢氧化镁[Mg(OH)2]和聚合物/纳米复合材料的阻燃性能及其机理,总结了国内外纳米阻燃体系的发展,提出阻燃纳米复合材料方面的研究方向与建议.     

食品类专业《仪器分析》教学内容的探讨与完善

《仪器分析》是食品类相关专业本抖生的专业基础课,目前存在着无专业性教材,且与生产和科研实际脱节,实验教学经费投入不够,综合性实验训练不足的现象。文章根据多年教学经验,针对食品类专业的特色,从实际需求出发,对《仪器分析》理论和实验教学内容提出了建议,并对教学方式提出改进。     

Content and Color Stability of Anthocyanins Isolated from Schisandra chinensis Fruit

In this work, a multivariate study based on Box-Behnken Design was used to evaluate the influence of three major variables affecting the performance of the extraction process of Schisandra chinensis anthocyanins. The optimum parameters were 5.5 h extraction time; 1:19 solid-liquid ratio and 260 r/min stirring rate, respectively. The extraction yield of anthocyanins was 29.06 mg/g under the optimum conditions. Moreover, many factors on the impact of heating, ultrasound, microwave treatment and ultraviolet irradiation on content and color stability of anthocyanins from Schisandra chinensis fruit were investigated. The results show that thermal degradation reaction of anthocyanins complies with the first order reaction kinetics, and the correlation coefficient is greater than 0.9950 at 40–80 °C. Ultrasound and microwave treatment has little effect on the stability of anthocyanins, and the extraction time of ultrasound and microwave should be no more than 60 min and 5 min, respectively. The anthocyanins degradation effect of UVC ultraviolet radiation is greater than UVA and UVB; after 9 h ultraviolet radiation, the anthocyanins content degradation of UVC is 23.9 ± 0.7%, and the ΔE* was changed from 62.81 to 76.52 ± 2.3. Through LC-MS analysis, the major composition of Schisandra chinensis anthocyanins was cyanidin-3-O-xylosylrutinoside.