表面活性剂对水性油墨胶体稳定性的影响

对阳离子、阴离子、两性和非离子表面活性剂对水性油墨胶体稳定性的影响进行了探讨。结果表明:(1)在水性油墨胶体溶液中加入十六烷基三甲基溴化铵(CTAB)浓度为0.14 mmol/L时,Zeta电位由初始的-37.9 mV变为12.7 mV;当CTAB浓度为0.86 mmol/L时,Zeta电位上升到34.1 mV。pH对CTAB的作用效果有较大影响,当CTAB浓度为0.5 mmol/L时,将体系pH从初始值3.3调节至11.7,Zeta电位相应地从38.6 mV降至23.7 mV,炭黑粒子的平均粒径最大增加值达13 nm。(2)加入十二烷基磺酸钠(SDS)的浓度为1 mmol/L时,Zeta电位达到-38.2 mV,而炭黑粒子的平均粒径下降了2 nm。(3)加入椰油酰胺丙基氧化胺(CAPO)的浓度为0.01 mol/L时,Zeta电位在体系pH约为6.0时达到等电点;体系pH为3.2时,Zeta电位达到最大值28.5 mV,炭黑粒子平均粒径最大增加幅度为9 nm。(4)加入脂肪醇聚氧乙烯(7)醚(AEO-7)的浓度为0.1 mol/L时,体系Zeta电位从-37.9 mV变为-16.3 mV,炭黑粒子平均粒径从初始的154 nm增至240 nm。加入AEO-9得到与AEO-7相同的影响趋势。     

聚胺抑制剂zeta电位和吸附量关系研究

用Zetasizer Nano90测量了PF-HAB和UlTRAHIB两种钻井液用聚胺抑制剂对未水化粘土和水化粘土Zeta电位的影响。结果表明无论粘土水化与否,聚胺抑制剂均能使粘土颗粒的Zeta电位升高,但不同的聚胺对粘土Zeta电位的改变幅度不同。采用损耗法近似计算了粘土吸附聚胺的量,结果表明聚胺抑制剂的吸附量与Zeta电位成正相关关系。     

增强垃圾渗滤液处理厂污泥脱水性能的研究

以污泥比阻(SRF)、毛细吸水时间(CST)、Zeta电位作为污泥脱水性能的评价指标,对显著影响污泥脱水性能的絮凝剂的添加条件进行优化,并结合傅里叶转换红外光谱(FTIR)对污泥脱水机理进行阐述。结果表明,最佳投加条件下,相比PAM和FeCl_3联用,PAM和Al2(SO4)3联用对污泥脱水性能更好。投加比为:6 mL的污泥投加1 mL的0.77%PAM联用6 mg Al_2(SO_4)_3,此条件下,SRF由3.49×10⁽¹¹⁾m/kg降至0.2×10(11)m/kg降至0.2×10⁽¹¹⁾m/kg,CST由30.2 s降至11.5 s,Zeta由-21.2 mV升至-6.4 mV。FTIR光谱研究也从机理上表明,PAM、Al(11)m/kg,CST由30.2 s降至11.5 s,Zeta由-21.2 mV升至-6.4 mV。FTIR光谱研究也从机理上表明,PAM、Al⁽³⁺⁾、Fe(3+)、Fe⁽³⁺⁾能够与污泥的O—H等官能团相互作用,并且在最佳投加条件下,PAM与Al_2(SO_4)_3联用在3 284.23 cm-1处的红外吸收峰峰值明显高于PAM与FeCl_3联用的红外吸收峰峰值。研究证明,此方法可提高西安市江村沟垃圾填埋场污泥脱水性能。     

微涡旋水力澄清器中颗粒物Zeta电位试验研究

以微涡旋水力澄清器水样中颗粒物的Zeta电位为研究对象,用微观视角探讨澄清器的净水机理,实现澄清器净水工艺的改进.静态试验初步选出合适的混凝药剂聚合氯化铝铁(PAFC)和助凝剂聚丙烯酰胺(PAM),动态试验阶段重点就PAFC和PAFC+PAM对原水的处理情况,对澄清器的运行状况进行检验.在一段时间内,单独投加PAFC时,测得翼片隔板反应区某取样口的水样浊度稳定在65.0～66.8 NTU,Zeta电位基本稳定在-13.6～-13.7 mV:投加PAFC+PA时,测得翼片隔板反应区同一取样口的水样浊度基本稳定在63.0～65.0 NTU,Zeta电位基本稳定在-13.0～-13.2 mV,证明了澄清器运行情况基本稳定.     

滤池反冲洗水回流强化混凝低浊微污染水特性

以低浊微污染配水为研究对象,通过调整PACl投药量来控制絮体Zeta电位,考察不同混凝特性下滤池反冲洗水(FBWW)回流对混凝效能的影响。结果表明:Zeta电位接近-11 mV时,FBWW回流对浊度具有良好的去除效果,沉后水浊度最大去除率为63.81%,高于其他电位下FBWW回流处理效果,沉后水中残余Al_P含量最低(0.271 mg·L^-1)。但此阶段下过高的回流(12%)会导致水中PACl的额外消耗,使原水颗粒物难以获得足够的混凝剂而脱稳,致使浊度、COD_Mn、Al_P、Al_D等上升。Zeta电位接近0 mV时,FBWW对浊度、COD_Mn、UV₂₅₄、Al_P均有良好的处理效果,Al_D同时也能保持相对较低的值。当回流比在9%时,沉后水COD_Mn去除率达试验最高值34.21%。Zeta电位接近+4 mV时,FBWW回流导致浊度、COD_Mn、Al_P、Al_D大幅上升,而 UV₂₅₄去除率得到提高。回流比为12%时,这种趋势最为明显,UV₂₅₄去除率达试验最高值60.67%。通过对砂后水与沉后水有机物残余进行研究对比,沉后水与砂后水有机物的去除效果存在明显差异性,+4 mV下UV₂₅₄、COD_Mn去除率均高于其他电位。     

强化混凝提高水厂除藻效果的试验研究

从混凝的Zeta电位出发，研究了强化混凝与Zeta电位和除藻、除浊之间的关系．发现对于浊度的去除．混凝剂的最佳剂量区Zeta电位在-14mV～14mV区域之间，但藻类脱稳去除的最佳Zeta电位则在-8m以上，对应的混凝剂投加量相应较高，此时藻类的去除率约可提高5～10个百分点甚至更高。水体pH是影响藻类和浊度去除效果的重要条件。混凝剂和预氧化剂的投加量会影响水体的pH值，混凝原水的pH值以在中偏碱性(7．0～8．0)较好。     

增强垃圾渗滤液处理厂污泥脱水性能的研究

以污泥比阻(SRF)、毛细吸水时间(CST)、Zeta电位作为污泥脱水性能的评价指标,对显著影响污泥脱水性能的絮凝剂的添加条件进行优化,并结合傅里叶转换红外光谱(FTIR)对污泥脱水机理进行阐述。结果表明,最佳投加条件下,相比PAM和FeCl_3联用,PAM和Al2(SO4)3联用对污泥脱水性能更好。投加比为:6 mL的污泥投加1 mL的0.77%PAM联用6 mg Al_2(SO_4)_3,此条件下,SRF由3.49×10~(11)m/kg降至0.2×10~(11)m/kg,CST由30.2 s降至11.5 s,Zeta由-21.2 mV升至-6.4 mV。FTIR光谱研究也从机理上表明,PAM、Al~(3+)、Fe~(3+)能够与污泥的O—H等官能团相互作用,并且在最佳投加条件下,PAM与Al_2(SO_4)_3联用在3 284.23 cm-1处的红外吸收峰峰值明显高于PAM与FeCl_3联用的红外吸收峰峰值。研究证明,此方法可提高西安市江村沟垃圾填埋场污泥脱水性能。     

Cu2+对活性污泥性质的影响

工业废水含有重金属离子,进入城市污水处理厂不可避免地对生物处理过程产生毒性.本研究采用SBR反应器考察Cu2+浓度对活性污泥性质的影响.结果表明,当Cu2+浓度较低时(＜2 mg/L),Cu2+对活性污泥的沉降性能、SOUR和Zeta电位影响较小,SVI、SOUR和污泥表面Zeta电位分别保持在67 mL/g、7.24 mg O2/(gMLSS·h)和38.41 mV,COD去除率为84.31％.但是,当Cu2浓度较高时(≥2 mg/L),COD去除率下降,污泥絮凝沉降性差,污泥表面Zeta电位降低,活性污泥具有发生膨胀的趋势.SVI升高至149 mg/L,污泥表面Zeta电位下降至21.21mV,SOUR下降至3.37 mg O2/(gMLSS·h),COD去除率下降至34.11％.     

十二烷基二甲基苄基氯化铵对原油碱洗脱酸反应的影响

针对高酸原油碱洗脱酸过程中反应速率较慢且乳化严重的问题,以十二烷基二甲基苄基氯化铵(DDBAC)为相转移催化剂和乳化抑制剂,利用电导率、Zeta电位和全功能稳定性分析等方法对原油与NaOH溶液之间反应速率和乳状液稳定性进行了研究。结果表明,DDBAC可以显著提高原油与碱液反应速率并且有效抑制乳化。在25℃,DDBAC质量浓度为400 mg/L时,反应速率提高了15倍;在反应温度为50℃,NaOH质量分数为4%时,随着DDBAC质量浓度的增加,碱液含油量和Zeta电位均显著降低,当DDBAC质量浓度为300 mg/L时,4%NaOH溶液油含量降至79.69 mg/L,减少51.79%,Zeta电位从-38.087 mV降至-27.97 mV。原油酸值经二级碱洗脱酸后可以降至0.41 mg(KOH)/g。     

TiO2/N-琥珀酰壳聚糖复合材料的制备及表征

以N-琥珀酰壳聚糖与TiO2复合制备了TiO2/N-琥珀酰壳聚糖复合材料。采用透射电镜(TEM)、傅里叶红外光谱(FTIR)、紫外-可见光谱(UV-Vis)、X射线衍射(XRD)、粒径及Zeta电位分析对复合材料进行表征。结果表明,TiO2表面羟基与N-琥珀酰壳聚糖分子中的羟基、酰胺、羧基相互作用形成了稳定的复合材料;复合材料中TiO2晶型呈锐钛矿型;复合材料平均粒径为50nm,Zeta电位达39mV;紫外-可见光谱显示,复合材料的光响应范围拓宽到可见光区,且对光的吸收能力显著增强,但在模拟太阳光下其光催化效率较TiO2有所下降。     

N,N-二甲基癸基氧化胺与鲑鱼精DNA相互作用的研究

通过浊度、紫外吸收和表面张力的测定,研究了N,N-二甲基癸基氧化胺(C10DAO)与鲑鱼精DNA的相互作用。结果表明:中性条件时C10DAO不能诱导DNA发生相分离;C10DAO浓度高于6.0 mmol/L的C10DAO-DNA体系达到临界pH时,静电相互作用导致体系浊度发生跃变;C10DAO浓度为6.0~16.0 mmol/L时,对应的临界pH改变显著。紫外吸收和表面张力结果也证实了相互作用的存在;荧光猝灭表明低质子化度的C10DAO可诱导DNA构象发生转变。     

DNA damage photoinduced by titanium dioxide in the presence of anionic vesicles under uv illumination: influence of sodium chloride concentration

The DNA damage caused by TiO2 under in vitro conditions by UV-A exposure in the presence of anionic vesicles of Aerosol OT (AOT) was investigated. The supercoiled form (S) in DNA plasmids was converted to the linear form (L) via the relaxed form (R). The DNA damage was slower in the presence of AOT vesicles prepared in aqueous NaCl solution. Moreover, the presence of AOT vesicles in solution after 6 h of UV irradiation was confirmed with an optical microscope. Probably, a fraction of the DNA was protected by random trapping during sonication. However, the addition of NaCl needed for the vesicle formation can decrease the TiO2 activity. On the other hand, in the absence of vesicles the NaCl concentration led to a profound influence on the adsorption of DNA onto the TiO2 surface. During UV irradiation, the degradation rate of DNA increased with increasing the salt concentration. Solutions containing vesicles were prepared at various NaCl concentrations between 10 mM and 75 mM. Consequently, the salt concentration had no significant effect on the DNA damage. The presence of NaCl can play a deleterious role during the photoinduced process. However, the encapsulation of a fraction of DNA is not excluded. In such conditions, the DNA could be protected against the reactive oxygen species.     

Thermodynamic Association Behaviors of Sodium Dodecyl Sulfate (SDS) with Poly(4-vinylpyridine <Emphasis Type="Italic">N</Emphasis>-oxide) (PVPNO) at Different pH Values and Ionic Strengths

The interaction of sodium dodecyl sulfate (SDS) with poly(4-vinylpyridine N-oxide) (PVPNO) at different pH values and ionic strengths has been studied by isothermal titration microcalorimetry, electrical conductivity and turbidity measurements. The solution pH significantly effects the formation of the PVPNO/SDS complex. At pH 1.5, the polymer PVPNO is a strong polycation, and the binding is dominated by electrostatic 1:1 charge neutralization with the anionic surfactant. At pH 6 and 8, the electrostatic attraction between SDS and PVPNO is weak, and the hydrophobic interaction becomes stronger. The effect of salt concentration on the interaction of SDS and PVPNO depends on the competition between the increase of interaction and the screening of interaction. This study based on the thermodynamic process gained deep insight into the effects of pH value and ionic strength on the interaction mechanism of surfactant with polyelectrolyte. We also constructed a simple model for the interaction of PVPNO and SDS system in different solution regions.     

油酸钠对酞菁铜颜料的分散作用

本文采用油酸钠对有机颜料酞菁铜进行改性,结果表明油酸钠可降低粒子Zeta电位,并有效调控有机颜料酞菁蓝的粒子尺寸及形貌.当水溶液中油酸钠浓度在0.040moL/L和0.500moL/L之间时,颜料粒子的平均粒径可达纳米级,Zeta电位可由-20mV减小到-60mV,体系的分散稳定性也得到明显提高.在油酸钠浓度为0.200moL/L时,颜料粒子粒径达到最小值(约66nm),而且总体比较均匀,基本呈现为球形;而油酸钠浓度较小(0.040 moL/L和0.064 moL/L)或较大(0.500moL/L)时,颜料粒子则主要以长棒状形式分散在体系中.     

Lyotropic liquid crystalline solutions of hydroxypropyl cellulose in water: Effect of salts on the turbidity and viscometric behavior

Effect of addition of salt on the viscometric behavior of the dilute or concentrated aqueous solution of hydroxypropyl cellulose (HPC) was determined by means of an Ubbelohde or a cone-plate viscometer. That effect on the turbidity of the dilute system was also determined. As salts, NaCl, LiCl, and thiourea were chosen. The turbidity and viscometric behavior for the dilute system, and the viscometric behavior for the concentrated system were greatly affected by salt type and concentration. With increasing NaCl or LiCl concentration, the cloud point decreased, [η] showed a maximum, Huggins' constant k′ showed a minimum, and the shear viscosity for concentrated isotropic solutions showed a maximum. The 45 wt % solution with no salt showed a viscometric behavior which was characteristic of lyotropic liquid crystals; however, with increasing NaCl concentration, a critical temperature at which the shear viscosity showed a maximum with respect to temperature shifted to lower temperature. This behavior was due to an increase in the turbidity, not due to a phase transformation. On the other hand, an addition of thiourea did not affect so greatly the turbidity and viscometric behavior as an addition of NaCl or LiCl did. We speculated different actions of NaCl and thiourea.     

纳滤膜流动电位及Zeta电位的研究

应用自主研发的测试装置对荷电纳滤膜的荷电性能进行了研究。根据流动电位的测试原理,以不同浓度、不同成分的盐溶液为荷电纳滤膜表面流动电位的测量介质,研究了不同浓度、不同的压力条件下对纳滤膜表面流动电位及Zeta电位测量的影响。     

The study of Sunset Yellow anionic dye interaction with gemini and conventional cationic surfactants in aqueous solution

In the present study, the interaction of an anionic azo dye, Sunset Yellow, with two cationic gemini surfactants with different spacer lengths (s = 3, 6 methylene groups) and their monomeric counterpart, dodecyl trimethyl ammonium bromide (DTAB), was investigated by surface tension, UV–Vis spectroscopy, and zeta potential measurements. The critical micelle concentration (CMC) was determined from plots of the surface tension (γ) as a function of the logarithm of total surfactant concentration. Moreover, the values of binding constants (K_b) of dye-surfactant complexes were calculated by UV–Vis spectroscopy. The UV–Vis spectra showed that the dye–surfactant interaction occurred in the solution at concentrations far below the CMC of each surfactant. The gemini surfactant with a shorter spacer showed stronger interaction with dye in comparison to DTAB and the gemini with longer spacer. The effect of surfactant chemical structure on solubilization of dye-surfactant aggregates at surfactant concentration above CMC was investigated by zeta potential.     

Stability of kaolinite dispersions in the presence of sodium and aluminum ions

The stability of colloidal kaolinite dispersions in the presence of NaCl and AlCl₃ was studied by measuring turbidity, electrophoretic mobility and adsorption. The kaolinite particles coagulated at pH 2.5–3.5 and were dispersed at pH >4.5. These results well obeyed the classic DLVO theory if the mean zeta potential of the kaolinite particles in aqueous solutions was taken into account in the computation of potential energy of electrical double layer repulsion, which suggests that the kaolinite particles might coagulate in the same way as normal colloidal particles. The kaolinite particles in aqueous aluminum salt solution only coagulated at a medium AlCl₃ concentration, and formed a stable dispersion at a high salt concentration. This is caused by Stern-layer adsorption of hydrolyzed aluminum species, probably adsorbed on the kaolinite surfaces through hydrogen bonds between the hydroxyl groups of the aluminum species and the oxygen atoms on the kaolinite surfaces.     

pH和盐浓度影响磺酸基团吸附乳铁蛋白的机理

磺酸基团是用来分离乳铁蛋白普遍被认可的配基,因此含有磺酸基团的层析剂是被用得最广泛的分离介质。通过对三种接有磺酸基团的层析介质,在不同pH和盐浓度时的静态吸附研究,得到了吸附的基本规律：随着pH或盐浓度的增大,吸附容量降低。利用分子模拟技术,比较了乳铁蛋白分子表面电势在不同条件时的变化,推测pH影响吸附的机理在于改变了蛋白表面氨基酸残基的质子化状态和分子表面电势,而盐浓度主要是屏蔽了蛋白和配基之间的相互作用,改变蛋白分子表面整体电势强弱,对电势分布没有明显影响。通过计算蛋白和配基之间的结合能,量化不同条件下的吸附能力,表征pH和盐浓度的影响。     

Interaction of DNA with Cationic Gemini Surfactant Trimethylene-1, 3-bis （dodecyldimethyl-ammonium bromide） and Anionic Surfactant SDS Mixed System

The interaction of DNA with cationic gemini suffactant trimethylene-1,3-bis （dodecyl dimethyl-ammonium bromide） （12-3-12） and anionic surfactant sodium dodecyl sulfate （SDS） mixed system has been investigated by measuring the fluorescence, zeta potential, UV-Vis spectrum, and circular dichroism. In the absence of SDS, owing to the electrostatic and hydrophobic interactions, 12-3-12 forms micelle-like structure on the DNA chain before the micellization in bulk phase. For the mixed system of 12-3-12 and SDS, the negative charges on SDS can compete against DNA to bind with cationic 12-3-12 because of the stronger interaction between oppositely charged surfactants, and thus, the catanionic mixed micelles are formed before the formation of DNA/12-3-12 complexes. There-after, the positive charges on the mixed micelles bind with DNA, and thus, the change of the zeta potential from negative to positive is distinctly different from the system without SDS. Meanwhile, the existence of SDS postpones the exclusion of ethidium bromide （EB） from DNA/EB complexes. The conformation of DNA undergoes a change from native B-form to chiral ψ-phase as binding with 12-3-12 process. Upon adding SDS to the DNA/12-3-12 complex solution, however, DNA is released to the bulk and the ψ-phase returns to B-form again.