离子型聚乙烯醇海绵的结构及性能

以聚乙烯醇（ＰＶＡ）为原料,采和缩醛化、发泡成型,接枝聚合的方法,制造了多孔泡沫海绵状况液材料,离子化聚乙烯醇海绵。结构分析表明,ｉ－ＰＶＡ海绵具有三维多孔结构,由于引入了大量的阴离子基团ｉ－ＰＶＡ海绵具有优异的吸液性能,临床使用证明,ｉ－ＰＶＡ海棉可用于白内障复明手术中的特殊用途。     

Pilates and telomere dynamics: A 12-month longitudinal study

Telomeres are dynamic structures that appear to be positively influenced by healthy lifestyle factors such as exercise. Pilates is an increasingly popular exercise modality that is reported to exert beneficial physiological effects in the body, although the cellular mechanisms are poorly understood. The aim of the present study was to investigate the influence of Pilates exercise on telomere length. This longitudinal study followed experienced female Pilates practitioners (n = 11, 50.8 ± 7.5 years) and healthy age- and sex-matched sedentary controls (n = 11, 49.3 ± 6.1 years) over a 12-month period. Leukocyte telomere length was quantified using qPCR. Circulatory inflammatory markers, mRNA gene expression, body composition, physical performance, and mental well-being were also assessed. Telomere length was comparable between Pilates practitioners and controls at baseline (Pre) and 12-months (Post) (p > 0.0125). Pilates practitioners displayed enhanced mRNA gene expression of antioxidant enzymes (SOD2 and GPX1), and lower body fat percentage and visceral fat rating, compared with sedentary controls (p < 0.0125). Over the 12-month longitudinal period, Pilates participants significantly increased dynamic balance (p < 0.05). In conclusion, long-term Pilates participation does not appear to influence telomere length. Nonetheless, Pilates exercise appears to increase antioxidant enzyme gene expression, effectively manage body composition, and improve dynamic balance.     

Mechanical and self-recovery properties of supramolecular ionic liquid elastomers based on host–guest interactions and correlation with ionic liquid content

Supramolecular materials have received considerable attention due to their higher fracture energy and self-recovery capability compared to conventional chemically cross-linked materials. Herein, we focus on the mechanical properties and self-recovery behaviours of supramolecular polymeric elastomers swollen with ionic liquid. We also gained insight into the correlation between ionic liquid content and mechanical properties. These supramolecular polymers with ionic liquid can be easily prepared from bulk copolymerization of the host–guest complex (peracetylated cyclodextrin and adamantane derivatives) and alkyl acrylates and subsequent immersion in ionic liquid such as 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. The supramolecular polymeric elastomers showed a self-recovery ability, which the conventional chemically cross-linked elastomers with ionic liquid cannot achieve.

Supramolecular ionic liquid elastomers showed higher fracture energy than chemically cross-linked ionic liquid elastomers and also self-recovery ability.     

Efficient separation of rare earths recovered by a supported ionic liquid from bauxite residue leachate

Bauxite residue (BR) contains substantial concentrations of rare-earth elements (REEs), but their recovery is a challenge. Acidic BR leachates typically comprise much higher concentrations of base elements (g L⁻¹) than those of the REEs (ppm). Thus, adsorbents that are highly selective for the REEs over the base elements are required for the separation. The novel supported ionic liquid phase (SILP) betainium sulfonyl(trifluoromethanesulfonylimide) poly(styrene-co-divinylbenzene) [Hbet-STFSI-PS-DVB] was evaluated for the uptake of REEs (Sc, Y, Nd, Dy) in the presence of base elements (Ca, Al, Fe) from BR leachates. Breakthrough curves from acidic nitrate and sulfate media were investigated, as both HNO₃ and H₂SO₄ are commonly used for leaching of BR. The SILP exhibited a superior affinity for REEs in both media, except in the case of Sc(iii) from the sulfate feed. The recovery rates of the trace amounts of REEs from the real nitrate feed were remarkably high (71.7–100%) via a simple chromatography separation, without requiring complexing agents or a pretreatment for the removal of interfering elements. The REEs were purified from the base elements and separated into three sub-groups (scandium, light REEs and heavy REEs) by an optimized elution profile with H₃PO₄ and HNO₃ in a single chromatographic separation step.

Rare earths are separated from base metals in bauxite residue leachate by a supported ionic liquid phase.     

Extraction of DNA from complex biological sample matrices using guanidinium ionic liquid modified magnetic nanocomposites

A series of guanidinium ionic liquid modified magnetic chitosan/graphene oxide (GIL-MCGO) nanocomposites have been prepared for DNA extraction via magnetic solid-phase extraction technology. These nanocomposites are of only 20 nanometers in diameter. Single stranded DNA or DNA sodium salts that were absorbed by GIL-MCGO could be quickly collected by an external magnet and extracted. The DNA extraction efficiency of 11 GIL-MCGO nanocomposites was evaluated using NanoDrop. Factors that could impact the DNA extraction process, such as pH, temperature, extraction time, and ionic strength were systematically investigated via single-factor experimental analysis. Under the optimum extraction conditions, a maximum DNA extraction capacity of 233.0 ± 0.4 mg g⁻¹ of GIL-MCGO nanocomposite was achieved. The solid phase extraction method based on GIL-MCGO nanocomposites has been demonstrated with the extraction of DNA from a series of complex sample matrices, including single stranded DNA samples, salmon sperm DNA sodium salt, human whole blood and E. coli cell lysate. The DNA extracted by using the GIL-MCGO nanocomposites are well suitable for PCR amplifications. In addition, an initial study on the interaction between GIL-MCGO and DNA was conducted: the preference of GIL-MCGO on DNA absorption with varying base composition was tested. Only a slight loss in the DNA extraction efficiency of GIL-MCGO was observed after four extraction–desorption cycles, proving excellent regeneration performance and recyclability of the GIL-MCGO nanocomposites in the DNA extraction process.

The DNA extracted from biological samples by using the GIL-MCGO nanocomposites are well suitable for PCR amplifications.     

Performance of butanol separation from ABE mixtures by pervaporation using silicone-coated ionic liquid gel membranes

This work aims at the separation of n-butanol from aqueous solutions by means of pervaporation using membranes based on gelled ionic liquids (IL). These membranes were mechanically stabilized with a double silicone coating using two polydimethylsiloxane (PDMS) films. The first step of the membrane preparation considered the formation of a gelled ionic liquid layer, which was formed using two different imidazolium-based ionic liquids: [omim][Tf₂N] and [bmim][Tf₂N], and two different phosphonium-based ionic liquids: [P_6,6,6,14][Tf₂N] and [P_6,6,6,14][DCA]. The gelation procedure was carried out on a porous paper support using a low molecular weight gelator. The membranes obtained from this method were tested in pervaporation assays to separate butanol from model ABE (Acetone–Butanol–Ethanol) fermentation solutions. These assays were done in an experimental setup especially built for this purpose. The pervaporation performance of these ionic liquid-based membranes was compared to that obtained with a single PDMS layer membrane. From these experimental results, butanol/water selectivity for [P_6,6,6,14][Tf₂N]-based membranes reached a value equal to 892, which is 150 times higher than the value obtained for a single PDMS layer membrane. Simultaneously, for the same IL, the transmembrane fluxes (kg h⁻¹ m⁻²) of butanol and water were 37% and 99.6% lower than the values obtained using a single PDMS layer membrane, respectively. The hydrophobic character of the selected ionic liquid and its relatively high values for the transport parameters can explain this experimental response.

This work aims at the separation of n-butanol from aqueous solutions by means of pervaporation using membranes based on gelled ionic liquids (IL).     

Diffusivity and free anion concentration of ionic liquid composite polybenzimidazole membranes

In this article, PBI composite membranes containing the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIM-NTf₂) at 1, 5, 10, 20 and 50 wt% (named PBI-IL-x) have been prepared by a casting method. The internal morphology of the membranes was analyzed by scanning electron microscopy (SEM), revealing that the incorporation of IL promotes the formation of porous channels. Thermal and mechanical stability was confirmed by thermogravimetric analysis (TGA) and tensile test measurements. The ionic transport through membranes was analysed by means of electrochemical impedance spectroscopy (EIS), showing a dependence on the IL loading, reaching a highest conductivity value of 1.8 × 10⁻² S cm⁻¹ for the PBI-IL-50 membrane at 160 °C. The experimental results showed a Vogel–Fulcher–Tammann (VFT) type relation for the ionic conductivity with temperature and the calculated activation energies suggest that ionic conduction in the films can occur by both hopping and vehicle-type mechanisms. Eyring''s absolute rate theory was also used to obtain activation enthalpy and entropy from the temperature dependence of the conductivity. Diffusivity and free ion number density were obtained by means of electrode polarization analysis to obtain more insight into the conduction in these composite membranes. Finally, the Debye length was calculated and related to both transport parameters.

PBI composite membranes containing 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIM-NTf₂) at 1, 5, 10, 20 and 50 wt% have been prepared and the conductivity has been analyzed by electrochemical impedance spectroscopy.     

Morphology and pervaporation performance of ionic liquid and waterborne polyurethane composite membranes

Blending an aromatic-selective ionic liquid (IL, namely 1-ethyl-3-methylimidazolium hexafluorophosphate, [emim][PF₆]) with waterborne polyurethane (WPU) enabled us to obtain [emim][PF₆]-modified waterborne polyurethane composite membranes. We characterized the structure and properties of the [emim][PF₆]/WPU composite membranes by ATR-FTIR, DSC, UV, SEM, EDX, swelling tests, and pervaporation testing. Characterization of the change in the morphology of the membranes in response to the IL loading indicated that a preferential interaction between the IL and soft segments of WPU was induced by hydrogen bonding. This interaction inhibited a potential interaction with benzene (Bz), which initially lowered the permeability. However, at high IL loading, the IL incorporation became ineffective owing to macrophase separation, which caused an increase in the permeability, as indicated by the SEM results. Swelling testing of the [emim][PF₆]/WPU composite membranes showed that the membranes exhibited preferential adsorption of Bz, and the swelling degree of the composite membranes in Bz solvent increased from 58% to 98% and remained almost constant in cyclohexane solvent as the IL content was increased. The [emim][PF₆]/WPU composite membranes enhanced the separation selectivity of Bz/Cy for an IL loading < 10 wt%. The best separation factor was 8.4, and the total flux was 0.19 kg (m² h)⁻¹ (50 wt% Bz/Cy mixtures at 50 °C) at w([emim][PF₆]) : w(WPU) = 10 : 100. In addition, the composite membrane exhibited excellent stability over long-term operation. These results demonstrated that the [emim][PF₆]/WPU composite membranes could be effective for separation of Bz/Cy mixtures by the pervaporation method.

Possible model of interactions in [emim][PF₆]/WPU composite membranes.     

Atomic-scale investigation of the heterogeneous structure and ionic distribution in an ionic liquid using scanning transmission electron microscopy

Ionic liquids show characteristic properties derived from them being composed of only molecular ions, and have recently been used as solvents for chemical reactions and as electrolytes for electrochemical devices. The liquid structures, i.e., ionic distributions, form when solutes are dissolved in ionic liquids and fundamentally affect the reactions and transfer efficiency in such solutions. In this study, we directly observe the liquid structure in a solution of the long-chain ionic liquid 1-octyl-3-methylimidazolium bromide (C₈mim Br) and barium stearate (Ba(C₁₇H₃₅COO)₂) using the annular dark-field method of scanning transmission electron microscopy (ADF-STEM). The ADF image shows a 10 nm-scale heterogeneity in the image intensity, which reflects the heterogeneous ionic distribution in the solution. The number density distributions of all the component ions (C₈mim⁺, Br⁻, Ba²⁺, and C₁₇H₃₅COO⁻) were estimated from the ADF image intensity and then visualized. These ionic distribution maps depicted the spatial relationships between the ions at the sub-nanometer scale and revealed that the heterogeneity is largely derived from the large differences in size, charge distributions, and van der Waals interactions.

Ionic liquids show characteristic properties derived from being composed of only molecular ions. The numbers of all constituent molecules and ions were quantitatively estimated from the image intensity and the origin of the heterogeneity in the ionic liquid was discussed.     

A novel viewpoint of an imidazole derivative ionic liquid as an additive for cobalt and nickel electrodeposition

Thin films of Co and Ni electroplated onto a copper electrode from acidic sulfate and Watts baths, respectively, were investigated. The use of an ionic liquid additive in the electrolyte is widespread for producing thin films by electrodeposition. In the present work, the influence of a new ionic liquid, namely, 1-methyl-3-((2-oxo-2-(2,4,5-trifluorophenyl)amino)ethyl)-1H-imidazol-3-ium iodide (Im-IL), in the electrodeposition of two metals was investigated using cathodic polarization (CP), cyclic voltammetry (CV), and anodic linear stripping voltammetry (ALSV) measurements and cathodic current efficiency (CCE%). The surface morphology of the Co- and Ni-coated samples was examined using Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM). The corrosion protection of the Co and Ni samples in a marine environment (3.5% NaCl solution) was studied by the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results show that the addition of Im-IL inhibits Co²⁺ and Ni²⁺ deposition, which leads to more fine-grained deposits, especially at low Im-IL concentrations. The inhibition of Co²⁺ and Ni²⁺ reduction in the presence of Im-IL ions occurs via adsorption, which obeys the Langmuir adsorption isotherm. The CCE% is higher in the presence of Im-IL. SEM images show smoother deposits of Co and Ni in 1 × 10⁻⁵ M and 1 × 10⁻⁴ M Im-IL solution respectively. The results prove that Im-IL acts as an efficient additive for electroplating soft Co and Ni films.

Thin films of Co and Ni electroplated onto a copper electrode from acidic sulfate and Watts baths, respectively, were investigated.     

Synthesis,structure and thermal properties of montmorillonite/ionic liquid ionogels

Sodium montmorillonite (Na-MMT) was synthesized as a result of two-stage processing of natural bentonite (Bent), and its particle-size distribution, structure and morphology were studied. It was found that the two-stage processing of the original clay resulted in a significant increase in the specific surface area (from 72 to 120 m² g⁻¹). The prepared Na-MMT powder was modified by two ionic liquids (ILs), namely, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMImNTf₂) and 1-butyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide (BMImNTf₂). Several methods, such as SEM, XRD, TG, DSC, FTIR spectroscopy were used to study the structure and thermal behavior of the produced ionogels. The effects of the IL cation on thermal characteristics of the Na-MMT/IL ionogels were studied. Using the DSC, characteristic temperatures of glass transition, crystallization and melting were determined for Na-MMT/IL composites. Taking into account the literature data and using the method of thermogravimetric analysis, it was shown that ionogel formation was accompanied by a decrease in the thermal stability of the IL.

Sodium montmorillonite (Na-MMT) was synthesized as a result of two-stage processing of natural bentonite (Bent), and its particle-size distribution, structure and morphology were studied.     

超嗜热古菌组蛋白HPhA单克隆抗体制备与初步应用

目的 制备针对超嗜热古菌组蛋白HPhA的单克隆抗体并进行鉴定。方法 以重组纯化蛋白HPhA为抗原。用聚乙二醇（PEG）法制备杂交瘤细胞，ELISA检测杂交瘤细胞分泌抗体的效价和类型，Western blotting分析抗体的特异性。结果 获得3株稳定分泌抗HPhA蛋白的单克隆抗体（MAb），3株单克隆抗体1A12、3C11、384分别属于IgG1、IgM和IgG2b亚类。ELISA和Western blotting结果显示，单克隆抗体3B4能特异性结合HPhA及PEA-HPhA重组蛋白。结论 抗HPhA单克隆抗体可用于HPhA和PEA-HPhA检测。     

Chromatographic separation of rare earths from aqueous and ethanolic leachates of NdFeB and SmCo magnets by a supported ionic liquid phase

The separation of rare-earth elements (REEs) from other components of end-of-life NdFeB and SmCo magnets was investigated by column chromatography. A carboxylic-acid functionalized supported ionic liquid phase (SILP) was studied as a stationary phase. The magnets were firstly leached with a dilute aqueous or ethanolic hydrochloric acid solution at room temperature. Leaching of REEs from a NdFeB magnet was similarly efficient with both lixiviants, but the REEs were more efficiently leached from a SmCo magnet with the ethanolic lixiviant. The SILP exhibited a high affinity towards trivalent cations of REEs, which were successfully recovered from the aqueous and ethanolic leachates of magnets. Divalent cations of iron and cobalt, which were the major components of the acidic aqueous leachates of magnets, were rejected by the SILP. Iron and cobalt were present as negatively charged chloro complexes in the ethanolic leachates of magnets, and were not recovered by the cation-exchanging SILP. A versatile column chromatography method is developed, suitable for the separation of REEs from iron and cobalt, either from aqueous or ethanolic leachates of permanent magnets.

Chromatographic separation of rare earths, iron and cobalt from the aqueous and ethanolic leachates of NdFeB and SmCo magnets.     

Micellization and thermodynamics study of ester functionalized picoline-based ionic liquid surfactants in water

A novel series of picoline-based ionic liquid surfactants, N-alkyoxycarbonyl-3-picoline bromides [C_nEmpy][Br] (n = 10, 12, 14), have been synthesized. The thermal stability, aggregation behavior and surface activity of the synthetic ionic liquid surfactants were investigated systematically though a series of methods, such as thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), tensiometry and conductivity. The thermodynamics of micellization of the ionic liquid surfactants solution were studied by using the conductivity method in the temperature range 278.15–318.15 K. The surface activity parameters and thermodynamics parameters were derived, respectively. The enthalpy–entropy compensation effect was further discussed by using relative thermodynamics parameters. It was found that the [C_nEmpy][Br] have moderate surface activity, and their critical micelle concentration (CMC) decreased with the ester-functionalized chain length and exhibited a U-shape with temperature. The calculation results of the thermodynamic parameters showed that the micellization processes of [C_nEmpy][Br] were spontaneous, endothermic at low temperature and exothermic at higher temperature.

The aggregation behavior of N-alkyoxycarbonyl-3-methyl pyridinium bromides [C_nEmpy][Br] in water was extended to the investigation of the effect of ester functionalized chain length on the thermodynamics of micellization in a wide temperature range.     

Solvent extraction of rare earths elements from nitrate media in DMDOHEMA/ionic liquid systems: performance and mechanism studies

Extraction of La(iii), Eu(iii) and Fe(iii) was compared in n-dodecane and two ionic liquids (ILs) (1-ethyl-1-butylpiperidinium bis (trifluoromethylsulfonyl)imide [EBPip⁺] [NTf₂⁻] and 1-ethyl-1-octylpiperidinium bis (trifluoromethylsulfonyl)imide [EOPip⁺] [NTf₂⁻]). Using the extractant N,N′-dimethyl-N,N′-dioctylhexylethoxymalonamide (DMDOHEMA), the effect of pH was investigated in detail to recover extraction mechanisms. The use of ILs as the organic solvent instead of n-dodecane, greatly enhances extraction efficiency, and an ionic liquid with a shorter alkyl chain [EBPip⁺] [NTf₂⁻] provides higher extraction than [EOPip⁺] [NTf₂⁻]. The mechanistic study points out that for low nitric acid concentrations ([HNO₃] ≤ 0.01 M), metal is extracted via a cation of the ionic liquids, while for higher nitric acid concentrations ([HNO₃] ≥ 1.0 M), extraction occurs through pure solvation mechanism of DMDOHEMA as in conventional diluents. This latter case is of high interest for applications, as higher extraction can be obtained without any loss of ILs by ion exchange mechanisms.

Extraction of La(iii), Eu(iii) and Fe(iii) was compared in n-dodecane and in two ionic liquids (ILs) [EBPip⁺] [NTf₂⁻] and [EOPip⁺] [NTf₂⁻]. Extraction mechanisms have been investigated as a function of pH.     

Characterization and dynamics of middle ear fluid and nasopharyngeal isolates of Streptococcus pneumoniae from 12 children treated with levofloxacin

Children who had acute otitis media and were treated with levofloxacin were assessed for the emergence of fluoroquinolone-resistant Streptococcus pneumoniae. Nasopharynx cultures were obtained from patients at the entry to and during levofloxacin therapy. All nasopharynx isolates (n = 59) from 12 children were levofloxacin susceptible without parC/E or gyrA/B mutations. Pneumococcal nasopharynx persistence was not associated with levofloxacin resistance.     

Electrodeposition of nickel in air- and water-stable 1-butyl-3-methylimidazolium dibutylphosphate ionic liquid

Nickel coating was obtained by potentiostatic electrodeposition in 1-butyl-3-methylimidazolium diethylphosphate ionic liquid without any additive. Further, cyclic voltammetry (CV) tests were used to investigate the electrochemical behaviour of Ni²⁺ in the ionic liquid, revealing that the electrodeposition of nickel in this ionic liquid is an irreversible process. It was revealed that the diffusion of Ni²⁺ is a rate-determining step in the electrodeposition process. Further, the influence of dissolved water and applied voltage on electrodeposition were also studied using scanning electron microscopy (SEM).

In this study, bright nickel coatings with nano-spherical grains were obtained in water- and air-stable ionic liquid.     

A methanol and protic ionic liquid Ugi multicomponent reaction path to cytotoxic α-phenylacetamido amides

The Ugi four component reaction of an aldehyde, amine, isocyanide and an ethanoic acid was effected smoothly in protic ionic liquids ethylammonium nitrate (EAN) and propylammonium nitrate (PAN) to afford analogues of α-phenylacetamido amides in good to excellent isolated yields. The corresponding reactions in [BMIM][PF₆] and the protic ionic liquid ethanolammonium nitrate (ETAN) failed. Microwave irradiation in EAN facilitated rapid access to three focused libraries, based on the parent isocyanide: cyclohexyl isocyanide, benzyl isocyanide and ethyl isocyanoacetate. Analysis of the structure activity relationship data suggested the presence of a bulky moiety originating from the isocyanide (cyclohexyl and benzyl) enhanced cytotoxicity. Removal of the acetylenic H-atom from the ethanoic acid moiety was detrimental to cytotoxicity. The most active analogues produced, N-(2-cyclohexylamino)-1-(4-methoxyphenyl)-2-oxoethyl-N-(3,5-dimethoxyphenyl)propiolamide, returned average GI₅₀ values of ≤1 μM across the cancer cell lines evaluated. Combined, these data suggest that analogues of this nature are interesting potential anti-cancer development leads.

The Ugi reaction (aldehyde, amine, isocyanide and an ethanoic acid) in the protic ionic liquids ethylammonium nitrate (EAN) and propylammonium nitrate (PAN) gave excellent yields of α-phenylacetamido amides.     

Basic ionic liquid as catalyst and surfactant: green synthesis of quinazolinone in aqueous media

Basic imidazolium-based ionic liquids not only possess the extraordinary physicochemical properties of ionic liquids, but also have excellent basicity and surfactivity. 1-Propyl-3-alkylimidazole hydroxide ionic liquids ([PRIm][OH]) were synthesized and their catalytic and surfactant behavior were studied in this work. [PRIm][OH] owned excellent surfactivity, and their alkyl chains and ion pairs benefit hydrophobicity and hydrophilicity respectively. The surfactivity of [PRIm][OH] increased with increasing alkyl chain length. [PRIm][OH] showed better catalytic performance than NaOH in the condensation of 2-aminobenzonitrile with cyclohexanone in aqueous medium, and the catalytic performance was well coincident with their surfactant behavior. [PRIm][OH] could decrease the interfacial tension of solvent effectively and form micelles in water. The formed micelles could solubilise more reactants into water and effectively increase the chance of contact between reactants and catalytic active sites. The catalyst dosage obviously affected catalytic performance. The catalytic system is a promising recyclable system.

[PRIm][OH] showed excellent catalytic properties in synthesis of quinazolinone in aqueous medium, owing to its excellent surfactivity and basicity.     

Micellization,surface activities and thermodynamics study of pyridinium-based ionic liquid surfactants in aqueous solution

The micellization and surface activity properties of long-chain pyridinium ionic liquids n-alkyl-3-methylpyridinium bromide ([C_nmpy][Br], n: the carbon numbers of hydrophobic tails, n = 12, 14, 16) in aqueous solution were systematically investigated through electronic conductivity measurement, surface tension, and ultraviolet-absorption spectra. The surface chemical parameters and thermodynamics parameters were obtained. The [C_nmpy][Br] ionic liquids exhibit higher surface activities than conventional surfactants with corresponding alkyl chain lengths. The effects of inorganic salts (LiBr, NaBr, MgBr₂), organic alcohols (C₂H₅OH, C₃H₇OH, C₄H₉OH, C₅H₁₁OH) and temperature on the critical micelle concentration (CMC) values of [C_nmpy][Br] aqueous solutions were also investigated. The CMC values remarkably decreased with the addition of inorganic salts. The CMC values increased slightly in the presence of ethanol, but decreased gradually as the chain length of the alcohol increased. The CMC values assumed a trend of decreasing and then increasing with the increase of temperature. The calculation results of thermodynamic parameters show that both adsorption and micellization processes of [C_nmpy][Br] are spontaneous; the enthalpy of [C₁₂mpy][Br] is negative at 293.15 K and becomes negative with temperature increasing. For [C₁₄mpy][Br] and [C₁₆mpy][Br] this transition occurs at 288.15 K and the micellization process is entropy-driven in the investigated temperature range.

This paper contains details on the micellization, surface activity properties, thermodynamics and effects of additives of [C_nmpy][Br].