离子表面活性剂和胶原间的相互作用

研究了二十烷基苯磺酸钠（SDBS）和溴化十六烷基吡啶翁（CPB）表面活性剂同胶原纤维（BAT）的反应。在酸性环境（pH＝3）和等电点条件（CrBATpH=6.5,SBAT PH=4)决定了吸附作用等温线。同时，研究了底物的膨胀变化（用αm表示膨胀度）。已经证实了离子表面活性剂对铬鞣和植物鞣胶原的吸收。发现SDBS对CrBAT的吸收与反应的pH值无关而取决于铬进一步吸收的活性位置的含量。在酸性区域，结合SDBS不使CrBAT纤维膨胀，而CrBAT在等电点条件下存在较轻微的膨胀。CPB与CrBAT的结合量较小，在同样的反应条件下，CPB在pH=6.5时的吸收实际与其对未鞣 的BAT的吸收相同。靠SBAT在高pH值下的稳定性，离子表面活性剂对SBAT的吸收要在pH=4时有效。预测SBDS的吸收更低，但等温线是S形相对于c.m.c.SDBS有一个滞后的段。CPB－SBAT和SDBS－BAT反应，当CPB对BAT吸收时纤维会发生轻微的膨胀。     

大豆油水界面上大豆11S球蛋白吸附膜的膨胀流变特性

本文采用轴对称滴形分析法（ADSA）检测了pH2．0和5．0条件下，大豆油／水界面上不同浓度（0．1—0．001％，w／w）的大豆11S球蛋白吸附膜的膨胀流变特征参数（膨胀模量、膨胀弹性、膨胀粘性及相角）随吸附时间的变化。实验表明，在温度（23℃）和体相溶液离子强度（0．05M）恒定的条件下，随着吸附时间的延长，表面膨胀模量增大，相角减小。膨胀弹性明显大于膨胀粘性，因此，从表面流变学的角度分析，油／水界面上粘弹性的大豆11S球蛋白吸附膜实际上是弹性的。膨胀模量随液滴体相蛋白浓度的增加而增大，受体相pH值的影响很大。pH2．0时，吸附膜的膨胀模量明显大于pH5．0时吸附膜的膨胀模量。     

十二烷基苯磺酸钠在纳米CaCO_3表面的吸附

为了更好地分析十二烷基苯磺酸钠(SDBS)作为分散剂时纳米CaCO3在水中分散的机制,研究水性体系中SDBS在纳米CaCO3表面的吸附情况。采用紫外可见分光光度法测定SDBS在纳米CaCO3表面的吸附量,讨论吸附SDBS后分散体系Zeta电位的变化,研究吸附的稳定性。实验结果表明:SDBS在纳米CaCO3表面的吸附量随着SDBS溶液质量浓度的增大而增加,当质量浓度大于2 g/L时,吸附达到饱和吸附;pH值对吸附量有一定影响,pH=7时的吸附量大于pH=11时的吸附量;吸附SDBS后,分散体系的Zeta电位有很大变化;SDBS在纳米CaCO3表面的吸附是一个自发过程,吸附比较稳定。     

纳米TiO2在水分散体系中的稳定性

研究pH值、不同离子性的表面活性剂和高分子分散剂聚乙烯吡咯烷酮对纳米二氧化钛水分散体系稳定性的影响。研究表明，体系pH值9时，溶胶最稳定；在等电点（pH值3．5）时，纳米微粒很快发生聚沉。阴离子表面活性剂达到一定浓度时，可提高溶胶的稳定性；阳离子表面活性剂在中性和碱性条件下，会破坏溶胶的稳定性，而当其偏酸性（pH值为5，但大于3．5）时，能提高胶体的稳定性；加入聚乙烯吡咯烷酮，可提高溶胶的稳定性。     

溶液化学特性对果聚糖在聚偏氟乙烯膜上吸附的影响

活性污泥体系中存在产生果聚糖的诸多微生物,研究其在膜表面的吸附行为有利于控制膜生物反应器中的膜污染.结果表明,果聚糖在聚偏氟乙烯膜上的吸附可在60 min内达平衡.随溶液pH值的增大,果聚糖吸附量先降低后增加,在pH=7.0处取得最小值,为20 mg/m2.而吸附量随离子强度的变化趋势则是先增加后降低,在离子强度为0.004处取得最大值,为39 mg/m2.果聚糖在聚偏氟乙烯膜表面的吸附等温线遵循兰格缪尔方程,并给出了不同溶液化学条件的吸附自由能.果聚糖与聚偏氟乙烯膜之间的吸附可能受静电力和范德华力的共同作用,且吸附是可逆的.     

羊毛吸附溶液中的溴代烷基三甲铵

研究了不同温度（15℃，25℃，35℃）下羊毛纤维在不同盐浓度溶液中对溴代烷基三甲铵的吸附规律，结果表明温度对溴代十六烷基三甲铵（CTAB）和溴代十二烷基三甲铵（DTAB）吸附的影响规律基本相同，而离子强度对它们吸附的影响略有不同。15℃时吸附量大于25℃和35℃时的吸附量，符合一般吸附放热的规律；但与一般规律有所不同的是，35℃时羊毛对CTAB和DTAB的吸附量均高于25℃时的吸附量。表面活性剂碳氢链长对羊毛吸附的影响是CTAB比DTAB更易被羊毛纤维吸附，与同系物碳氢链长增加更易吸附的规律相符合；而离子强度对羊毛吸附的影响则与温度有关，温度较低（15℃）时，离子强度对吸附的影响不明显，温度较高（25℃，35℃）时，离子强度对羊毛纤维吸附CTAB和DTAB的规律并不一致，25℃时CTAB及35℃时DTAB低浓区的吸附受离子强度影响符合离子强度增大吸附量增加的一般规律；而其它情况下它们的吸附受离子强度的影响不遵从此规律。     

用羧甲基纤维素对漂白针叶木浆的简单改性

用羧甲基纤维素（CMC）处理漂白针叶木浆。为了在纤维表面引入更多的带电基团,CMC吸附可在特定条件（60℃,pH值12.5,CMC加入量1%,浆浓5%）下进行。纸浆的打浆情况、pH值、CMC取代度以及电解质浓度对CMC的吸附量均有重要影响。经CMC处理后纸浆保水值明显增大,并且保水值的增大与纸浆成纸内结合强度和抗张强度的提高相关。用环境扫描电子显微镜（ESEM）对用水或电解液抄造的纸张进行了进一步的研究。实验中CMC吸附条件与实际造纸系统类似,因此,这种表面改性方法可能具有实用价值。     

枇杷叶多糖酶法提取工艺优化及其离子交换层析纯化

单因素试验和响应面试验得到酶法提取枇杷叶多糖最佳条件为提取时间2.95 h、提取温度41 ℃、酶用量15.6 mg/g,多糖提取率为8.03%。研究枇杷叶多糖在离子交换填料DEAE Sepharose CL-6B上的吸附行为,考察缓冲液pH值和离子强度对吸附等温线的影响。结果表明,在实验范围内,吸附平衡数据符合单分子层吸附的Langmuir方程,枇杷叶多糖在DEAE-Sepharose CL-6B上的吸附量随着缓冲液pH值的上升而增加,低离子强度的缓冲液有利于多糖的吸附。实验确定枇杷叶多糖离子交换柱层析进样条件为pH 8.0条件下,选取不含NaCl的缓冲液,通过离子交换柱层析后枇杷叶多糖被分为3 个组分,得率分别为32.66%、1.22%和3.12%。     

表面活性剂在氨基甲酸酯类农药污染土壤上的吸附研究

以氨基甲酸酯类农药为目标污染物,选用两种典型的表面活性剂（阴离子型SDS和非离子型Tween80）,探讨表面活性剂在土壤-水-有机污染物复杂体系中的吸附行为。SDS和Tween80在土壤上的吸附等温线呈现增加趋势,最终达到吸附饱和,饱和吸附量顺序为SDS>Tween80;土壤性质对表面活性剂吸附有较大的影响,两种表面活性剂在黄壤上的吸附量均要高于红壤上的吸附量;当土壤中存在氨基甲酸酯时,两种表面活性剂在土壤颗粒上的吸附量均有所增加。     

焙烧层状氢氧化镁铝对溴离子吸附性能研究

研究了500℃下焙烧层状氢氧化镁铝对溴离子吸附性能,考察了吸附时间、吸附剂用量、吸附温度、吸附初始pH值等条件对吸附性能的影响.实验结果表明,焙烧层状氢氧化镁铝对溴离子具有较好的吸附性能,35℃下饱和吸附量为133.33mg/g,其吸附等温线可以用Langmuir等温方程描述.     

Interaction of mixture of anionic surfactants with collagen

Study focused on interaction of collagen fibres of collagen I with anionic surfactants sodium dodecylbenzene sulphonate (SDBS), sodium dodecyl sulphate (SDS) and their mixtures at pH = 6, at two ionic strengths (I = 0.06 mol L(-1) and I = 0.4 mol L(-1)) and laboratory temperature. Surfactants and their mixtures were characterised by their critical micelle concentration (c.m.c.), composition of mixed micelles and interaction factor beta according to Rubingh. Dependency of c.m.c. on mixture composition has an opposite tendency at both ionic strengths, which proves the greater influence of added electrolyte on behaviour of SDS than of SDBS. Interaction was evaluated by means of binding isotherms and mass swelling degree alpha(m). The bound quantity partly depends on mixture composition, partly on ionic strength. SDS and mixtures containing its greater quantities are bound more than SDBS (approx. 150% related to SDBS). Increased ionic strength of the environment increases bound quantity in approximately same manner, heedless of adsorbate composition. Even composition of the mixture after interaction with fibres does not markedly alter from initial composition. Fibre swelling is affected by composition of swelling mixture similarly to binding - it increases with growing quantity of surfactants. Greater ionic strength acts against collagen swelling, and at given ionic strength (I = 0.4 mol L(-1)) swelling attains half values compare to swelling at low ionic strength (I = 0.06 mol L(-1)). There are characteristic concentrations of both surfactants and their mixtures (c(s) approximately 0.5 - 1.0 mmol L(-1)) that do not produce swelling. It is assumed that this range of concentrations corresponds to amount of surfactants bound to collagen through electrostatic forces and thus to temporary increase in fibre hydrophobity.     

碎解条件对OCC废纸碎化影响以及碎解助剂的优选

该实验选择废旧瓦楞箱纸板（OCC）为研究对象,从预处理时间、浆浓、转子转速和碎解温度等几个方面研究不同的碎解条件对废纸碎化的影响,确定在不添加碎解助剂情况下的最优碎解条件,即满足碎解所需时间最短、能耗较低和获得碎纸片含量最少的条件;其次,实验通过选用6种不同的表面活性剂分别添加到OCC废纸中,优选出最佳的碎解助剂十二烷基苯磺酸钠,同时,研究预处理时间、碎解温度和十二烷基苯磺酸钠用量对废纸碎化的影响;最后,对未添加碎解助剂和添加碎解助剂的OCC废纸浆的滤水性能和纤维特性做了评价和比较.     

pH-induced alterations in stratum corneum properties

Skin-cleansing compositions based on alkyl carboxylates (soaps) have a higher irritation potential than those based on syndet surfactants such as alkyl isethionates or alkyl ether sulphates. Contributing factors include inherent differences in the irritation potential of soaps and syndet surfactants, pH-induced changes in surfactant solution chemistry, and the direct effects of pH on the physical properties of the stratum corneum (SC). Past work has not directly addressed the effect of solution pH on the SC itself and its potential role in cleanser-induced skin irritation. In the current work, alterations to SC properties induced by buffered pH solutions and two strongly ionizable surfactants, sodium dodecyl sulphate and sodium lauryl ether sulphate, at different pH values are measured. By utilizing optical coherence tomography (OCT) and infrared (IR) spectroscopy we have directly measured physical changes in SC proteins and lipids. Our results indicate that SC swelling, which reflects alterations to SC structural proteins, is increased significantly at pH 10, compared to pH 4 and 6.5. The transition temperature (T(m)) of SC lipids is found to increase at pH 10, compared to pH 4 and 6.5, suggesting a more rigid SC lipid matrix. Surfactants cause a further increase in swelling and lipid rigidity. Some aspects of what these results mean for SC physical properties as well as their implications to potential mechanisms of surfactant-induced skin irritation are discussed.     

纳米CaCO3在水中的分散

 选择水为分散介质,通过添加分散剂和超声波的作用对纳米CaCO₃进行分散。测试分散体系的透光率、zeta电位和体系中纳米CaCO₃粒子的粒径以表征分散效果。通过对六偏磷酸钠(SHMP)、多聚磷酸钠(SPP)和十二烷基苯磺酸钠(SDBS)3种分散剂的分散效果比较,证明SDBS能提高纳米CaCO₃在水中分散性,是一种较合适的分散剂。探讨了分散剂用量、分散体系pH值和超声波作用时间对分散效果的影响。当SDBS用量为0.14%,pH值为8.5,超声波作用时间为5 min时,纳米CaCO₃在水中的分散效果较好。     

Enhanced soil washing of phenanthrene by mixed solutions of TX100 and SDBS

Increased desorption of hydrophobic organic compounds (HOCs) from soils and sediments is a key to the remediation of contaminated soils and groundwater. In this study, phenanthrene desorption from a contaminated soil by mixed solutions of a nonionic surfactant(octylphenol polyethoxylate, TX100) and an anionic surfactant (sodium dodecylbenzenesulfonate, SDBS) was investigated. Phenanthrene desorption depended on not only aqueous surfactant concentrations and phenanthrene solubility enhancement but also the soil-sorbed surfactant amount and the corresponding sorption capacity of sorbed surfactants. The added surfactant critical desorption concentrations (CDCs) for phenanthrene from soil depended on both sorbed concentrations of surfactants and their critical micelle concentrations (CMCs). Phenanthrene desorption by mixed solutions was more efficient than individual surfactants due to the low sorption loss of mixed surfactants to soil. Among the tested surfactant systems, mixed TX100 and SDBS with a 1:9 mass ratio exhibited the highest phenanthrene desorption. Mixed micelle formation, showing negative deviation of CMCs from the ones predicted by the ideal mixing theory, was primarily responsible for the significant reduction of soil-sorbed amounts of TX100 and SDBS in their mixed systems. Therefore, mixed anionic-nonionic surfactants had great potential in the area of enhanced soil and groundwater remediation.     

Fast‐swelling Superabsorbent Hydrogels from Poly(2‐hydroxy ethyl acrylate‐co‐sodium acrylate) Grafted on Starch

Fast‐swelling highly porous superabsorbent hydrogels were synthesized through a rapid radical polymerization under normal atmospheric conditions. To synthesize a biopolymer‐based superabsorbent hydrogel, 2‐hydroxyethyl acrylate (HEA) and sodium acrylate (AANa) were grafted on the starch backbone in an aqueous solution. The graft copolymerization reaction was carried out in the presence of ammonium persulfate (APS) as an initiator and ‐methylenebisacrylamide (MBA) as a crosslinker in a homogeneous medium. The chemical structure of the hydrogels was confirmed by FT‐IR spectroscopy and thermogravimetric analysis (TGA). The morphology of the samples was examined by scanning electron microscopy (SEM). The results indicated that with increasing the amount of sodium acrylate both swelling capacity and swelling under load (AUL) were increased. Preliminary swelling and deswelling behaviors of the hydrogels were also studied. The effects of pH and inorganic salt on the swelling behavior of the hydrogels were investigated as well.     

HYDRATION OF SODIUM CHLORIDE BOUND BY CASEIN AT MEDIUM WATER ACTIVITIES

SUMMARY –In dried mixtures of sodium chloride and casein, one part of the salt is bound by the protein and the other part is crystalline or amorphous, depending on drying conditions. Bound and free forms of salt are in equilibrium, which is strongly dependent on the actual water activity. If changes in water activity take place slowly, this equilibrium may be maintained; whereas, during rapid changes nonequilibrium conditions are likely to be attained. The bound, crystalline and amorphous sodium chlorides produce characteristic changes in the water vapor sorption properties of salt-casein-mixtures. Sorption isopsychric curves describing the equilibrium water content as a function of the composition at constant water activity were determined between the water activities of 0.50 and 0.75 at 25°C, using the isopiestic technique. These curves were analyzed in terms of the hydration of bound sodium chloride ion pairs. The hydration increases progressively with increasing water activity; also, with the amount of sodium chloride added up to the point where the protein becomes completely saturated with ion pairs. From the isopsychric curves, the sorption isotherms of salt-casein-complexes of definite salt contents were constructed in the water activity range investigated.     

Modeling tetracycline antibiotic sorption to clays

Sorption interactions of three high-use tetracycline antibiotics (oxytetracycline, chlortetracycline, tetracycline) with montmorillonite and kaolinite clays were investigated undervaried pH and ionic strength conditions. Sorption edges were best described with a model that included cation exchange plus surface complexation of zwitterion forms of these compounds. Zwitterion sorption was accompanied by proton uptake, was more favorable on acidic clay, and was relatively insensitive to ionic strength effects. Calcium salts promoted oxytetracycline sorption at alkaline pHs likely by a surface-bridging mechanism. Substituent effects among the compounds in the tetracycline class had only minor effects on sorption edges and isotherms under the same solution pH and ionic strength conditions. At low ionic strength, greater sorption to montmorillonite than kaolinite was observed at all pHs tested, even after normalizing for cation exchange capacity. These results indicate that soil and sediment sorption models for tetracyclines, and other pharmaceuticals with similar chemistry, must account for solution speciation and the presence of other competitor ions in soil or sediment pore waters.