阳离子染料可染尼龙6制备及性能

以己内酰胺(CPL)为原料,在聚己内酰胺(PA6)的缩聚阶段加入间苯二甲酸-5-磺酸钠(5-SSIPA)和聚乙二醇2000(PEG 2000),制备了阳离子染料可染PA6(ECD-PA6)。通过染色实验、差示量热扫描、热失重分析、X射线衍射分析、流变测试等探讨了5-SSIPA和PEG的加入对阳离子染料可染PA6染色性能、结晶性能、热力学性能和流变性能等的影响。结果表明,随着5-SSIPA加入,聚合物染色性提高,聚合物相应的熔融和结晶的温度范围变宽,同时分解温度降低,热稳定性良好,且聚合物熔体黏度上升,损耗模量(G″)增加;PEG的加入使得CD-PA6聚合物晶型改变,染色性进一步提高,且能有效加强聚合物分子链的流动性,降低聚合物熔体黏度,熔体弹性响应更明显。     

Insight into the adsorption mechanism of cationic dye onto biosorbents derived from agricultural wastes

This study investigated the phenomenon and mechanism of adsorption of methylene green 5 (MG5) on three pristine biosorbents: golden shower pod (GS), coconut shell (CC), and orange peel (OP). The results showed that the biosorbents possessed low specific surface areas, but abundant functional groups. Adsorption was strongly affected by the solution’s pH and ionic strength. As revealed in the kinetic study, equilibrium was rapidly established, requiring low activation energies; a removal rate of 30%–87% was achieved within 1?min. The maximum Langmuir adsorption capacities at 30°C exhibited the following order: GS (106?mg/g)?>?OP (92?mg/g)?>?CC (59?mg/g). Thermodynamic experiments suggested that the adsorption occurred spontaneously (?ΔG°) and exothermically (?ΔH°). The primary adsorption mechanisms involved electrostatic attraction, hydrogen bonding formations, and n-π interaction. Thermogravimetric analysis (TGA) revealed that three biopolymer components (i.e., hemicellulose, cellulose, and lignin) played controlling roles in the adsorption process. Thus, these three agricultural residues can be considered potential low-cost adsorbents for efficient dye adsorption applications.     

Local structure investigations of accumulated damage in irradiated MgAl2O4

Damaged structures in the MgAl₂O₄ spinel induced by swift heavy ions were investigated using the X-ray absorption near edge structure (XANES) and small angle X-ray scattering (SAXS). Increasing the fluence of 100 MeV Xe ions leads to increased SAXS intensity and XANES spectral changes on both Mg and Al K-edges. The damaged regions of ion tracks were observed by SAXS to be cylindrical in shape with a diameter of 5 nm. The theoretical XANES spectra indicated that the changes in the experimental spectra were due to the cationic disordering between tetrahedral and octahedral sites. This disordering caused an increase in the inversion degree of the cations. Furthermore, the quantitative analysis of the XANES spectra revealed the preferential occupation of cations at the octahedral sites at high fluence.     

14-3(OH)-14(2Cl)/Brij-30混合水溶液的相图及流变行为

采用重量法在25℃时绘制了双子阳离子表面活性剂2-羟亚丙基-1,3-双(二甲基十四烷基氯化铵)(14-3(OH)-14(2Cl))/非离子表面活性剂月桂醇聚氧乙烯醚(Brij-30)/水三元体系的相图。通过目测并结合偏光显微镜研究了相图中几个不同的相区。用稳态和动态剪切流变方法得到了单纯双子阳离子表面活性剂及几个相区内不同聚集体的流变特性。根据测定的流变参数分析和判断相区内聚集体的流体行为及结构特征。结果表明,黏弹性蠕虫状胶束的流变行为遵循Maxwell模型,具有单一松弛时间。     

基于证据理论的民机电源系统故障诊断方法

D-S证据理论在民用飞机电源系统的故障诊断中有着广泛的应用，但是处理高度冲突的数据依然存在困难。为了解决证据理论工程应用中的这一难题，提出了一种基于改进证据理论的民机电源系统故障诊断方法。新方法引入民机电源系统故障的历史数据，定义了修正因子的概念，并且用经典数据案例验证了这一诊断方法。数据案例验证的结果表明，新方法在数据融合的过程中更快更准确的识别出目标，提高了故障诊断结果的可靠性和精确性，而且增强了故障诊断系统的性能，是证据理论在工程应用中的一个突破。     

Acid dyeable and printable acrylic fabrics treated with cationic aqueous polyurethane

An acid dyeable acrylic fabric has been obtained by the pretreatment with cationic aqueous polyurethane, containing different amounts of quaternary nitrogen. Cationic polyurethane has the ability to interact with the carboxylic groups in the acrylic fabrics, as well as providing basic sites suitable for acid dyeing. The prepared polyurethane has been identified with FTIR, and the effect of the pretreatment conditions on the dyeability and printability of the fabrics has been investigated. The color strength values and the fastness properties of the dyed and printed samples, reveal the ionic interaction between the sulphonic groups in the acid dye molecules and the quaternary nitrogen on the fabrics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

从硫酸烧渣中获取高品位铁精矿的技术

通过矿物学研究查明了硫酸烧渣的矿物学性质。烧渣含铁为57.1%,杂质为石英、金云母、石膏等矿物;石英等矿物被包裹在三氧化二铁中,石膏填充在金属缝隙中或包裹在金属体外围。细颗粒间的团聚不利于磁选,通过重选摇床和阳离子反浮选脱硅联合工艺流程,显著提高铁精矿品位。铁总回收率大于85%。     

Novel Cholesterol-Based Cationic Lipids as Transfecting Agents of DNA for Efficient Gene Delivery

The design, synthesis and biological evaluation of the cationic lipid gene delivery vectors based on cholesterol and natural amino acids lysine or histidine are described. Cationic liposomes composed of the newly synthesized cationic lipids 1a or 1b and neutral lipid DOPE (1,2-dioleoyl-l-α-glycero-3-phosphatidyl-ethanolamine) exhibited good transfection efficiency. pEGFP-N₁ plasmid DNA was transferred into 293T cells by cationic liposomes formed from cationic lipids 1a and 1b, and the transfection activity of the cationic lipids was superior (1a) or parallel (1b) to that of the commercially available 3β-[N-(N'',N''-dimethylaminoethyl)-carbamoyl] cholesterol (DC-Chol) derived from the same cholesterol backbone with different head groups. Combined with the results of agarose gel electrophoresis, transfection experiments with various molar ratios of the cationic lipids and DOPE and N/P (+/−) molar charge ratios, a more effective formulation was formed, which could lead to relatively high transfection efficiency. Cationic lipid 1a represents a potential agent for the liposome used in gene delivery due to low cytotoxicity and impressive gene transfection activity.     

Poly-γ-glutamate-based Materials for Multiple Infection Prophylaxis Possessing Versatile Coating Performance

Poly-γ-glutamate (PGA) possesses a nylon-like backbone and polyacrylate-like carboxyl groups, and shows an extraordinary solubility in water. In this study, the effective synthesis and structural analysis of some water-insoluble PGA ion-complexes (PGAICs) using cationic surfactants, hexadecylpyridinium (HDP), dodecylpyridinium, benzalkonium and benzetonium, were examined. We demonstrated their spontaneous coating performance to the surfaces of different materials (i.e., plastics, metals, and ceramics) as potent anti-staphylococcal and anti-Candida agents. The tests against Staphylococcus aureus revealed that, regardless of a variety of materials, PGAICs maintained surface antimicrobial activity, even after the water-soaking treatment, whereas those against Candida albicans indicated that, among PGAICs, PGA/HDP complex is most useful as an anti-fungal agent because of its coating stability. Moreover, the log reduction values against Influenza A and B viruses of PGA/HDP-coated surfaces were estimated to be 5.4 and 3.2, respectively, suggesting that it can be dramatically suppressed the infection of influenza. This is to our knowledge the first observation of PGA-based antiviral coatings.     

酰胺咪唑啉硫酸二甲酯织物柔软剂的合成

采用硬脂酯、二乙烯三胺及硫酸二甲酯合成了阳离子咪唑啉柔软剂，介绍了其合成路线和制备工艺，该产品较双烷基二甲基氯化铵柔软剂有更好的手感和润湿性。