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1.
程国斌  韩梅  王刃  马伟 《应用化学》2005,22(10):1092-1095
研究了NH4 型斜发沸石对盐水中钾离子的吸附行为,考察了竞争阳离子等对铵型斜发沸石吸附钾离子的影响。结果表明,NH4 型斜发沸石对钾离子具有较强的选择吸附性与较大的饱和吸附容量,受钾离子初始浓度的影响,NH4 型斜发沸石吸附钾离子的行为在沸石相K 平衡分数YK 为0.5时发生较大转折。竞争阳离子的存在在不同程度上抑制了铵型斜发沸石对钾离子的吸附,特别是钾离子与钠离子的相对比例直接影响NH4 型斜发沸石对混合液中钾离子的选择交换能力。  相似文献   

2.
利用电导实验技术跟踪弱碱性阴离子树脂吸附低浓度游离酸的行为 ,研究了外加盐和醇等介质对吸附的影响。实验结果表明 ,弱碱性阴离子树脂吸附低浓度游离酸 ,其吸附速率随外加盐和醇的增加而减小  相似文献   

3.
提出了用镶炭泡塑处理含阴离子表面活性剂的废水,并通过实验证实,经活化的泡塑对LAS有明显的富集作用,且发现将活化过的活性炭填镶进去,可形成具有复合功能的处理剂,对含LAS废水的处理效果更佳。  相似文献   

4.
The interaction of H2S with both massive and supported on SiO2 silicotungstic acid at 300°C produces additional sites of H2S adsorption.  相似文献   

5.
聚电解质与相反电荷表面活性剂的相互作用   总被引:2,自引:0,他引:2  
罗娟  高保娇 《化学通报》2003,66(2):134-137
通过透光度测定、电导滴定和粘度法考察了阳离子聚电解质聚苯乙烯 4 乙烯基吡啶硫酸甲酯盐与阴离子表面活性剂十二烷基硫酸钠 (SDS)的相互作用。研究表明 ,在表面活性剂未过量时 ,二者之间的静电作用占主导地位 ,并且当二者电荷总量相等时 ,生成的复合物沉淀最多 ;在表面活性剂过量后 ,复合物可部分溶解 ,溶解的原因是疏水相互作用。本文初步阐述了二者的作用机理  相似文献   

6.
The effects of drug-surfactant and polymer on the acid hydrolysis of acetohydroxamic acid (AHA) have been studied at room temperature in 2% (v/v) dioxane medium. Kinetic data corresponding to the reaction with drug micelles are analyzed by using the pseudo-phase ion exchange model. The binding constant and first-order rate constant in micellar media in presence of AMYTP+-Drug, AMYTP+-β-Cyclodextrine, AMYTP+-SDS, AMYTP+-PEG, AMYTP+-TX-100, AMYTP+-CTAB, have been studied in 0.5 M HCl media.  相似文献   

7.
研究阴、阳离子表面活性剂混合体系(十二烷基氯代吡啶,辛基磺酸钠,辛基三乙基溴化铵/十二烷基苯磺酸钠)在硅胶,纯水和硅胶,矿化水界面上的吸附作用,探讨阴(阳)离子表面活性剂的存在对阳(阴)离子表面活性剂吸附作用的影响.结果表明,阴离子表面活性剂的存在基本不影响阳离子表面活性剂在带负电固体表面的吸附;而阳离子表面活性剂的存在却使本来吸附量就不大的阴离子表面活性剂在带负电的固体表面上不再吸附.在矿化水中阳离子表面活性剂的吸附量比在纯水中明显降低.从硅胶表面吸附机制解释了所得结果.  相似文献   

8.
以三氧化二铝陶瓷膜为载体,以钼酸根阴离子为模板离子,1-乙烯基咪唑为功能单体,1,6-二溴己烷为交联剂,采用表面印迹和接枝聚合方法制备了能选择性吸附Mo(Ⅵ)的新型印迹陶瓷膜(IIP-PVI/CM).采用红外光谱、X射线光电子能谱、热重分析及扫描电子显微镜等方法对陶瓷膜进行结构表征.研究了pH值对吸附性能的影响,当pH值范围为2~4时,IIP-PVI/CM具有良好吸附能力;动力学和热力学结果表明,IIP-PVI/CM对Mo(Ⅵ)的吸附符合准二级动力学模型和Langmuir吸附模型;当pH=4.0和温度为30℃时,IIP-PVI/CM对Mo(Ⅵ)具有良好选择性,Mo(Ⅵ)对W(Ⅵ)的选择性系数高达7.48;动态吸附结果表明,IIP-PVI/CM对W(Ⅵ)和Mo(Ⅵ)的吸附饱和时间分别为24和47 min,饱和吸附量分别为0.163和0.672 mmol/100 g,动态吸附时IIP-PVI/CM亦具有良好选择性;经9次吸附与解吸后,IIP-PVI/CM对Mo(Ⅵ)吸附容量仍可达到初始值的92%,再生和循环使用性能良好.  相似文献   

9.
唐雪娇  曹梦  毕成良  张宝贵 《化学学报》2007,65(23):2771-2775
利用滴加法合成了球形含Ni2+交联壳聚糖, 并通过胺化引入大量活性氨基, 再经除镍制成对重金属镍离子具有较好吸附能力的新型吸附剂[P-C-CTS(Ni)]. 通过Ni2+吸附容量的测定, IR及XPS分析, 验证了合成技术路线的正确性. 通过研究pH值对吸附量的影响, 初步讨论了无柠檬酸根(Cit)配位体存在时, 吸附剂对Ni(II)的吸附为螯合作用. 通过Cit存在条件下(cNicCit=0.852 mmol•L-1), 吸附剂对Ni(II)离子和Cit的吸附量随pH值的变化, 结合相应pH值下金属镍的形态分布, 探讨了其对Ni(II)的吸附机理, 研究认为不仅仅是简单的螯合作用, 其吸附机理和吸附量与溶液中金属离子的存在形式有关, 引入静电吸附原理解释了吸附剂对Ni(II)的吸附现象.  相似文献   

10.
The 1HNMR spectra of gemini cationic surfactant 1,3‐Propane diaminium N, N‐didodecyl‐2‐hydrxyl‐N,N,N′N′‐tetramethyl‐dichloride (ClC12H25‐(CH3)2N‐CH2CH(OH) CH2N(CH3)2 C12H25 Cl), abbreviated to GC12NCl solutions were determined in the presence of toluene, phenyl ethane, benzyl alcohol, or 2‐phenylethanol. Based on observations, probable solubilization sites of the substrate molecule within the micelles are discussed. The examined results indicate that the polarity of aromatic solutes affects their solubilization site in the micelle solution. The methylene in long chain of GC12NCl shows a single signal in the presence of toluene and phenyl ethane, however, when benzyl alcohol or 2‐phenylethanol is in existence, the peak of ethylenes in long chain Gemini surfactant splits into an upfield signal and a downfield signal in the solubilization system with enhancement of molar ratio of aromatic solutes to the sufactant. The addition of benzyl alcohol and 2‐phenylethanol causes a downfield shift of the methyl signal, the other signal were up field shifted by the addition of the phenyl derivatives. From the dependence of chemical shifts of GC12NCl on solubilizate concentration, it is ascertained that at low solubilizate contents the aromatic solutes are solubilized by adsorption at the micelle‐water interface. With further addition of aromatic solutes, the solubilization site of the solubilizate varied gradually from the mantle of the surfactant micelle to its inner core.  相似文献   

11.
大孔弱碱性树脂对高水溶性磺酸类染料中间体的吸附   总被引:9,自引:0,他引:9  
龙超  张全兴  陈金龙 《应用化学》2004,21(10):997-0
大孔弱碱性树脂对高水溶性磺酸类染料中间体的吸附;大孔弱碱性阴离子交换树脂;芳香磺酸化合物;吸附热力学  相似文献   

12.
A cost-effective, iron- and manganese-oxide-supported clinoptilolite-based rock was prepared. Based on its nanoporous structure, it worked as a nanoreactor, thereby providing enhanced functionalities. The mono- and bimetallic Fe- and Mn-oxide-supported clinoptilolite was thoroughly characterized with thermoanalytical FT-IR, XRD, SEM, and XPS spectroscopy. All the spectral procedures that were used confirmed the occurrence of a new MnO2 phase (predominantly birnessite), including mostly amorphous iron oxi(hydr)oxide (FeO(OH)) species on the surface of the above-synthesized adsorbents. The synthesized products validated a considerably higher adsorption capacity toward Pb(II) pollutants compared to the natural clinoptilolite. The following order of a(max) toward Pb(II) was found: MnOx-zeolite (202.1 mg/g) > FeO(OH)-MnOx-zeolite (101.3 mg/g) > FeO(OH)-zeolite (80 mg/g) > natural zeolite (54.9 mg/g). The adsorption equilibrium data were analyzed by the two-parameter empirical isotherm models Langmuir, Freundlich, and BET as well as the three-parameter Redlich–Peterson isotherm.  相似文献   

13.
This present study aimed to delineate Rumex hastatus D. Don crude extract (Rh.Cr), n-Hexane, ethyl acetate, aqueous fractions (Rh.n-Hex, Rh.ETAC, Rh.Aq) and rutin for antidiarrheal, antisecretory effects, anti-spasmodic, gastrointestinal transient time, anti H. pylori, antiulcer effects, and toxicology. The preliminary phytochemical analysis of Rumex hastatus showed different phytoconstituents and shows different peaks in GC-MC chromatogram. Rumex hastatus crude extract (Rh.Cr), fractions, and rutin attributed dose-dependent (50–300 mg/kg) protection (0–100%) against castor oil-induced diarrhea and dose-dependently inhibited intestinal fluid secretions in mice. They decreased the distance traversed by charcoal in the gastrointestinal transit model in rats. In rabbit jejunum preparations, Rh.Cr and Rh.ETAC caused a concentration-dependent relaxation of both spontaneous and K+ (80 mM)-induced contractions at a similar concentration range, whereas Rh.n-Hex, rutin, and verapamil were relatively potent against K+-induced contractions and shifted the Ca2+ concentration–response curves (CRCs) to the right, Rh.Cr (0.3–1 mg/mL) and Rh.ETAC (0.1–0.3 mg/mL) shifted the isoprenaline-induced inhibitory CRCs to the left. Rh.n-Hex, Rh.ETAC and rutin showed anti-H. pylori effect, also shows an inhibitory effect against H+/K+-ATPase. Rumex hastatus showed gastroprotective and antioxidant effects. Histopathological evaluation showed improvement in cellular architecture and a decrease in the expression of inflammatory markers such as, cyclooxygenase (COX-2), tumor necrosis factor (TN,F-α) and phosphorylated nuclear factor kappa B (p-NFƙB), validated through immunohistochemistry and ELISA techniques. In RT-PCR it decreases H+/K+-ATPase mRNA levels. Rumex hastatus was found to be safe to consume up to a dose of 2000 mg/kg in a comprehensive toxicity profile. Docking studies revealed that rutin against H+/K+-ATPase pump and voltage-gated L-type calcium channel showed E-values of −8.7 and −9.4 Kcal/mol, respectively. MD simulations Molecular Mechanics Poisson Boltzmann surface area and molecular mechanics Generalized Born surface area (MMPBSA/GBSA) findings are consistent with the in-vitro, in-vivo and docking results.  相似文献   

14.
利用高压容积法辅以卸压升温脱附排水法, 测定金属K修饰多壁碳纳米管对H2的吸附储存容量. 结果表明, 在室温(25 ℃), 7.25 MPa实验条件下, x%K0-MWCNTs (x%=30%~35%, 质量百分数)对H2的吸附储存容量可达3.80 wt%(质量百分数), 是相同条件下单纯MWCNTs氢吸附储量的2.5倍; 室温下卸至常压的脱附氢量为3.36 wt%(占总吸附氢量的~88%), 后续升温至673 K的脱附氢量为0.41 wt%(占总吸附氢量的~11%). 利用LRS和H2-TPD-GC/MS等谱学方法对H2/K0-MWCNTs吸附体系的表征研究表明, H2在K0-MWCNTs上吸附存在非解离 (即分子态)和解离(即原子态)两种吸附态; 在≤723 K温度下, H2/K0-MWCNTs体系的脱附产物几乎全为H2气; 723 K以上高温脱附产物不仅含H2, 也含有CH4, C2H4和C2H2等C1/C2-烃.  相似文献   

15.
测定了不同浓度NP-40(cNP-40)存在下各尺寸COM或COD晶体的吸附量;采用X射线衍射和红外光谱研究吸附前后晶体是否发生晶相改变;采用ζ电位仪测定吸附后晶体表面的ζ电位随cNP-40的变化。结果表明:不同尺寸COM、COD对NP-40的吸附能力大小顺序为:50 nm > 100 nm > 1 μm >> 3 μm > 10 μm;相同尺寸的晶体,COM的吸附量大于COD。随着cNP-40增加,3 μm和10 μm的COM、COD晶体的吸附曲线为S型,而50 nm、100 nm、1 μm的COM、COD晶体的吸附曲线为直线型。加入NP-40后,ζ电位绝对值与各晶体的吸附密度成正相关。提出了草酸钙晶体吸附NP-40的分子模型。晶体尺寸越小,对NP-40的吸附量越大。非离子表面活性剂虽然自身不带电荷,但吸附到COM、COD晶体表面后可以通过位阻斥力来增加晶体悬浮液的稳定性,有利于抑制草酸钙结石的形成。  相似文献   

16.
为探究CaOx结石的形成机理,测定了不同浓度NP-40(cNP-40)存在下各尺寸COM或COD晶体的吸附量;采用X射线衍射和红外光谱研究吸附前后晶体是否发生晶相改变;采用ζ电位仪测定吸附后晶体表面的ζ电位随cNP-40的变化。结果表明:不同尺寸COM、COD对NP-40的吸附能力大小顺序为:50 nm > 100 nm > 1μm > > 3μm > 10μm;相同尺寸的晶体,COM的吸附量大于COD。随着cNP-40增加,3μm和10μm的COM、COD晶体的吸附曲线为S型,而50 nm、100 nm、1μm的COM、COD晶体的吸附曲线为直线型。加入NP-40后,ζ电位绝对值与各晶体的吸附密度成正相关。提出了草酸钙晶体吸附NP-40的分子模型。晶体尺寸越小,对NP-40的吸附量越大。非离子表面活性剂虽然自身不带电荷,但吸附到COM、COD晶体表面后可以通过位阻斥力来增加晶体悬浮液的稳定性,有利于抑制草酸钙结石的形成。  相似文献   

17.
研究了尺寸分别为50 nm和3μm的一水草酸钙(COM)和二水草酸钙(COD)晶体对不同电荷表面活性剂的吸附差异,包括阴离子型表面活性剂磺基琥珀酸钠二辛酯(AOT)、阳离子型表面活性剂十六烷基三甲基溴化铵(CTAB)和非离子型表面活性剂壬基酚聚氧乙烯醚(NP-40),探究了尿液中带不同电荷的分子对纳米、微米尿微晶的影响。结果表明,表面活性剂的吸附量大小为AOTCTABNP-40,即阴离子型表面活性剂的吸附量最大,非离子型表面活性剂的吸附量最小;晶体尺寸相同时,COM的吸附能力稍大于COD;吸附表面活性剂后,晶体表面的ζ电位绝对值都增大,有利于抑制晶体的团聚和沉降。提出了晶体吸附不同表面活性剂的分子模型。不同电荷表面活性剂与纳/微米COM、COD晶体之间存在不同的相互作用。表面活性剂吸附量越大,沉降越慢,对晶体悬浮液的稳定效果越明显。  相似文献   

18.
Recombination rate coefficients of protonated and deuterated ions KrH+, KrD+, XeH+ and XeD+ were measured using Flowing Afterglow with Langmuir Probe (FALP). Helium at 1600 Pa and at temperature 250 K was used as a buffer gas in the experiments. Kr, Xe, H2 and D2 were introduced to a flow tube to form the desired ions. Because of small differences in proton affinities of Kr, D2 and H2 mixtures of ions, KrD+/D3+ and KrH+/H3+ are formed in the afterglow plasma, influencing the plasma decay. To obtain a recombination rate coefficient for a particular ion, the dependencies on partial pressures of gases used in the ion formation were measured. The obtained rate coefficients, αKrD+(250 K) = (0.9 ± 0.3) × 10−8 cm3 s−1 and αXeD+(250 K) = (8 ± 2) × 10−8 cm3 s−1 are compared with αKrH+(250 K) = (2.0 ± 0.6) × 10−8 cm3 s−1 and αXeH+(250 K) = (8 ± 2) × 10−8 cm3 s−1.  相似文献   

19.
Adsorption of n-pentane, triethylamine, diethyl ether, acetonitrile and chloroform has been investigated on pyrogenic alumina (S=140 m2 g−1). The results of our studies have shown the presence of active sites on the surface of pyrogenic alumina with irreversible adsorption of electron-donating molecules and CHCl3 and the dependence of energetic surface properties on electronic structure of adsorbate, quantity of adsorbed substance and hydration degree of the surface. On the hydrated oxide surface the water molecules screen the active sites of the surface, which resulted in changing of interaction energy of adsorbent-adsorbate and decreasing the region of irreversible adsorption of organic bases and CH-acid. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Ab initio cluster quantum chemical calculations at the Hartree–Fock (HF/Lanl2dz) and correlated second-order Moller–Plesset perturbation theory (MP2/Lanl2dz) levels were performed for NO and N2O interactions with Ag+ and Cu+ ion-exchanged zeolites. The interaction energies were estimated in a conventional way and also corrected for basis set superposition errors. It was shown that the highly dispersed Ag+ counterions establish twofold coordination to the lattice oxygens on the zeolite surface, similar to the case of Cu+ ions. However, both NO and N2O bind relatively strongly to the Cu active sites of Cu+ ion-exchanged zeolites than those of the Ag+ site of the Ag+ ion-exchanged zeolites. Based on the results of these calculations, the two different forms of adsorption for these molecules on the catalyst surface, the nature of their binding and characteristics of the adsorption properties have been discussed. Finally, some comparisons with the results obtained by a variety of density functional theory calculations on target systems have been presented.  相似文献   

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