牛血清白蛋白在NVP/HEMA无规共聚物水凝胶上的吸附研究

合成了不同含水量的N-乙烯吡咯烷酮(NVP)／甲基丙烯酸-β-羟乙酯(HEMA)共聚物水凝胶．研究了温度、pH值，蛋白质初浓度及离子强度等因素对牛血清白蛋白吸附性能的影响．采用紫外分光光度法测定BSA的吸附量．结果表明，蛋白质初浓度越高．温度越高，离子强度越大；蛋白质内部更多的疏水性氧基酸残基暴露于外部．吸附量增加：在等电点pH=4．7附近蛋白质沉积量最大．     

碱木素的近红外光谱吸收机理的研究

通过碱木素模型物对醌、邻醌和香兰素的溶液在800～900 nm的近红外光谱波段内的吸收谱图的对比发现,对醌和邻醌在此波段产生较强的吸收,而香兰素基本上没有吸收,证明了碱木素的醌型结构在800～900 nm波段内产生特征吸收。对银杏和夹竹桃磨木木素碱处理前后的溶液在800～900 nm波段内的吸光度的差别分析,发现夹竹桃的磨木木素的吸光度的相对变化更大,这是由于夹竹桃磨木木素经碱处理后产生了更多的醌型结构。这也是在硫酸盐法蒸煮过程中在800～900 nm波段内阔叶材的蒸煮液吸光度大于针叶材的蒸煮液吸光度的主要原因。     

碱性过硫酸钾法测定水质总氮的影响因素

碱性过硫酸钾氧化法测定总氮时经常出现空白值异常高的现象,本文通过实验研究发现:实验室环境、过硫酸钾的纯度、碱性过硫酸钾溶液存放时间、消解时间、消解温度等因素对测定均有影响.本文对这些因素进行了实验分析并提出了改进意见,对鄱阳湖水样进行了加标回收实验,结果令人满意.     

Evaluation on dispersion behavior of the aqueous copper nano-suspensions

This paper presents a procedure for preparing a nanofluid which is solid-liquid composite material consisting of solid nanoparticles with sizes typically of 1-100 nm suspended in liquid. By means of the procedure, Cu-H(2)O nanofluids with and without dispersant were prepared, whose sediment photographs and particle size distribution were given to illustrate the stability and evenness of suspension with dispersant. Aiming at the dispersion of nano-Cu is regarded as the guide of heat transfer enhancement, the dispersion behavior of Cu nanoparticles in water were studied under different pH values, different dispersant types and concentration by the method of zeta potential, absorbency and sedimentation photographs. The results show that zeta potential has good corresponding relation with absorbency, and the higher absolute value of zeta potential and the absorbency are, the better dispersion and stability in system is. The absolute value of zeta potential and the absorbency are higher at pH 9.5. Hexadecyl trimethyl ammonium bromide (CTAB) [corrected] and sodium dodecylbenzenesulfonate (SDBS) can significantly increase the absolute value of zeta potential of particle surfaces by electrostatic repulsions, and polyoxyethylene (10) nonyl phenyl ether (TX-10) can form a thick hydration layer on the particle surfaces by steric interference, which leads to the enhancement of the stability for Cu suspensions. In the 0.1% copper nano-suspensions, the optimizing concentrations for TX-10, CTAB [corrected] and SDBS are 0.43, 0.05, and 0.07%, respectively, which have the best dispersion results.     

Taguchi optimized synthesis of collagen-g-poly(acrylic acid)/kaolin composite superabsorbent hydrogel

A novel biopolymer-based hydrogel composite was synthesized through chemical crosslinking by graft copolymerization of partially neutralized acrylic acid onto the hydrolyzed collagen. The Taguchi method, a robust experimental design, was employed for the optimization of the synthesis based on the swelling capacity of the hydrogels. This method was applied for the experiments and standard L16 orthogonal array with five factors and four levels. In the synthesis of the composite superabsorbent, N,N′-methylene bisacrylamide (MBA) as crosslinker, ammonium persulfate (APS) as initiator, acrylic acid (AA) as monomer, neutralization percent (NU), and collagen/kaolin weight ratio were used as important factors. From the analysis of variance of the test results, the most effective factor controlling equilibrium swelling capacity was obtained and maximum water absorbency of the optimized final product was found to be 674 g/g. The surface morphology of the gel was examined using scanning electron microscopy. Furthermore in this research, swollen gel strength of composite SAPs already swollen under realistic conditions (saline solution absorbency under load) was determined.     

Application of selected natural sources on mulberry silk fabric

Silk finds an important place for its elegance, softness, luster, sheen, strength, uniformity suitable for the production of respective valuable textile garments and apparels. Due to the amphoteric character of silk protein polymer, the overall behavior of silk will be enriched when it is applied with natural resources. Based on these considerations, it is proposed in this research work to treat mulberry silk fabric with recovered sericin protein in addition with natural finishing sources like aloevera, amla and nochi in varied combinations followed by coloration with some selected natural sources. After these applications, the silk fabric was undergone for some testing for the determination of color value, fastness behavior, tensile strength, absorbency character, anti-odor and retention aspects, and FTIR graphs. The outcome of the results are convinced to the expectations suitable for the applications in the textile industries for garment and apparel utilities.     

灵芝多糖含量的红外光谱预测模型研究

利用傅里叶变换红外光谱仪(FTIR)测定不同等级贵州灵芝的傅里叶变换红外光谱,选择最佳的敏感波段组合构造吸光度变量,分析了吸光度变量与灵芝多糖含量的相关性,建立灵芝多糖含量的红外光谱预测模型并进行检验。结果表明:不同等级灵芝的红外光谱图基本相似,峰形相同;所选定的吸光度变量与灵芝多糖含量之间显著相关,灵芝多糖含量的预测模型及其检验结果的拟合度均达到显著水平,这说明可用红外光谱法来预测灵芝多糖含量。     

超吸水中国粘土/聚丙烯酸复合材料的制备与表征

本文采用共聚合法,以过硫酸钾作为发剂,N-N-亚甲基双丙烯酰胺作为交联剂,亚硫酸钠作为催化剂,合成了不同组成的SAPC样品系列.对比不同样品,找出中国粘土含量和丙烯酸含量对吸水和保水能力的影响.与原始粘土相比,中国粘土在SAPC中的层间距离有所扩大.SAPC中粘土含量对吸水性的影响表明,在45%含量以下,水的吸收率随粘土含量的增加而增加,而粘土含量的进一步增加降低了水的吸收性.在不同丙烯酸重量百分比样品中,最佳吸收率在丙烯酸重量百分比25%～35%之间.所得聚合物复合材料具有约190 g/g的高吸水性.     

PAAM高吸水树脂反相悬浮聚合

采用反相悬浮聚合法,通过部分中和丙烯酸与丙烯酰胺共聚制备了聚(丙烯酸-丙烯酰胺)(PAAM)高吸水树脂,讨论了聚合过程主要影响因素对其吸液性能的影响,并对其进行了FTIR、TGA测试,得到最佳的合成工艺配方:单体质量浓度为30%,中和度N为75%,丙烯酸与丙烯酰胺的摩尔比为7∶3,交联剂、引发剂和分散剂质量浓度分别为0.065%、0.7%和0.5%(相对于单体总质量),单体溶液的滴加速度为2～3mL/min,聚合温度和时间分别为70℃和1.5h。此时在蒸馏水、0.9%NaCl溶液%(wt)中最大吸水倍率分别为Qw=1300g/g、Qs=93g/g(Qw为蒸馏水中吸水倍率,Qs为0.9%NaCl溶液中的吸水倍率,下同),树脂在320℃之前都是比较稳定的,可以适应较高的使用温度。     

Superabsorbent Capability and High Retention Ability of China Clay (Kaolinite)/Polyacrylic Acid Composites for Aqueous Solution

Majority of superabsorbent polymers (SAPs) yet reported either have low gel strength or high production cost. Therefore, we synthesized a novel polyacrylic acid-grafted China clay (Kaolinite) super-absorbent polymer composite (SAPC) with high thermal stability, low cost of production and superior sorption and retention capability for water and salt solution. The resulting SAPCs were extensively characterized and analysed by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Results suggested that the composites were thermally stable. Water absorbency increased with increase of clay content up to 45%, while further increase in clay content decreased the water absorbency. Percentage of acrylic acid (AA) and clay by weight shows the optimum absorbency in 35% and 40% respectively. Crosslinker and initiator contents were optimized to be 0.5% and 0.3% by weight respectively. The resulting polymer composite showed high water absorbency of about 785 g/g and 103 g/g of 1% NaCl solution with above 90% retention ability at 50 oC.