bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of the Cloud Point of C12EO6 and C12EO8 Nonionic Surfactants: Effect of Additives
Authors: Alibrahim Moussa 
Published: December 2013

Abstract
Significant change in the cloud point of the nonionic surfactant solutions is observed by adding foreign substance. The aqueous solutions of these surfactants show complex phase behaviour including liquid-liquid separation at higher temperature. Electrolytes as well as nonelectrolytes have a large effect on the cloud point (CP) of C12EO6 and C12EO8 nonionic surfactants, because of their effect on water structure and their hydrophilicity. The presence of NaI and KI in the systems leads to a substantial increase in the cloud point of 2 wt% of the C12EO6 and C12EO8 solutions, but the increase is relatively less with KI than with NaI. Moreover, the cloud point decreases in the presence of NaF, NaCl and NaBr, and also similar identical observation was seen in the cloud point with KF, KCl and KBr, respectively. Furthermore, the results show that the addition of the tetramethyl ammonium bromide (TMABr) decreases the cloud point of the C12EO6 and C12EO8, whereas the addition of tetrabutyl ammonium iodide (TBAI) increases the cloud point of the above systems. The clouding phenomenon of the aqueous C12EO6 and C12EO8 systems in the presence of various additives is discussed.
Synthesis and Emulsification Properties of Organosilicone Modified Sodium Sulfonate of Alkanolamide Succinic Acid Monoester with Palm Oil
Authors: Wang Chen , duo Li Tian , yu Feng Sheng 
Published: December 2013

Abstract
Surfactants are widely used in the leather-making processes. The structure and property of surfactant obviously affect the quality and performance of leather. In this paper, a novel anionic surfactant, organosilicone modified sodium sulfonate of alkanolamide succinic acid monoester with palm oil was synthesized. Firstly palm oil was amidated with diethanolamine, then grafted with hydroxy-terminated silicone oil, esterified with maleic anhydride and sulphited with sodium bisulfite in sequence. The emulsification properties and fatliquoring performance of the prepared surfactant were tested. The influence of the mass percentage of reactants, the reaction temperature and time on the surface tension, the emulsifying activity and stability of the prepared surfactant were investigated. The FT-IR spectra analysis showed that under optimised conditions the novel surfactant was obtained. The fatliquoring application experiments showed that the novel surfactant is an excellent leather fatliquor.
Synthesis and Surface Properties of Novel Gemini Surfactants
Authors: Zhang Zhang , Zhen-Xian Zhang , Yu-rong Liu , Yu Zhang , Jie Chen 
Published: December 2013

Abstract
Novel Gemini surfactants containing amide group linkage were prepared with fatty acid, diamine and dihalide by simple organic reaction, and characterized with IR, and elemental analysis (EA). As the results show, the structures of the products obtained correspond to the target compounds designed. By surface tension scanning, these Gemini surfactants have excellent surface activity with low c.m.c. and surface tension, the lowest c.m.c value was 9.12 × 10−6 mol/L for surfactant Bi-18(4).
An Advanced Method for the Preparation of Erucyl Dimethyl Amidopropyl Betaine and Acid Solution Properties
Authors: Lu Hongsheng , Zhang Xuan , Quan Hongping , Dai Shanshan , Zhang Tailiang , Huang Zhiyu 
Published: December 2013

Abstract
In this paper, an improved method for the preparation of erucyl dimethyl amidopropyl betaine (EDAB) was provided. The synthesis conditions were investigated. N,N-dimethyl-N′-erucyl-1,3-propylenediamine was synthesized by the reaction of erucic acid with N,N-dimethyl-1,3-propylenediamine at 170°C for 7 h, and then the intermediate was reacted with sodium chloroacetate in the mixture of methanol and water (3:7 v/v) at 60°C. The product was obtained after 6 h. The compounds were confirmed by IR and 1H-NMR. The properties of EDAB acid solution were also studied. The results indicated that viscosity of acid solution increased with decreasing hydrochloric acid concentration and was mainly controlled by surfactant concentration and temperature. The viscosity of an acid solution was maximum when the concentration of hydrochloric acid was at 15 wt%.
Development and Validation of Micellar-Enhanced Spectrofluorimetric Method for Determination of Sulpiride in Pharmaceutical Formulations and Biological Samples
Authors: Shah Jasmin , Jan Muhammad Rasul , Khan Muhammad Naeem , Inayatullah  
Published: December 2013

Abstract
Sensitive and simple spectrofluorometric method has been developed and validated for the quantification of sulpiride in pure, commercial formulations, human plasma and urine in the presence of sodium dodecyl sulphate (SDS) surfactant micelle. The experimental parameters like buffer, surfactant type and volume were studied. A linear relationship was found between sulpiride concentration and fluorescence intensity in the range of 0.02 μg mL–1–7.0 μg mL–1 containing 0.2 M sodium dodecyl sulphate with λex 292 nm and λem 343 nm with a correlation coefficient of 0.9987. The limit of detection (LOD) and limit of quantification (LOQ) was found to be 1.9 × 10–2 μg mL–1 and 5.9 × 10–2 μg mL–1 respectively. The proposed method was successfully applied for the determination of sulphiride in pure and dosage form; the percentage recoveries agreed well with the label value. The effect of common excipients used as additive in pharmaceutical formulations was studied and no interferences was found. Similarly the effect of some common cations and compounds present in urine and plasma were also investigated and the method was found free of interferences. The method was further extended to the in-vitro determination of sulphiride in spiked human plasma and urine samples with percentage recoveries from 98.33%–99.75% and 95.67%–101.67% respectively. The results of the proposed method have been compared with the literature HPLC method and no significant difference was found between them.
Cleanability of Textile Materials in Liquid CO2
Authors: Dutschk Victoria , Sutanto Stevia , Calvimontes Alfredo 
Published: December 2013

AbstractCleanability of well-characterised textile materials of different types – cotton, polyester and wool – in liquid carbon dioxide (CO2) have been systematically investigated under different process conditions. It was found that the soil removal, which is represented with the soiling additional density (SAD), strongly depends on the kind of investigated textile materials. The use of a commercial detergent significantly improved the cleanability of all textile materials under study and slightly reduced the redeposition of soil in the case of wool fabric. In addition, by using optical roughness analysis, some topographical changes in the fabric structure after cleaning were studied.
Preparation and Evaluation of β-Carotene Containing Microemulsion
Authors: Yan Xiuhua , Wang Zhengwu 
Published: December 2013

Abstract
Microemulsions (O/W, W/O and B.C.) formed in Tween80/ethanol/ethyl butyrate/water system were identified by phase diagram determination and conductivity measurement at 25 °C. Comparative studies were made, by means of dynamic light scattering, viscosity and UV measurements, on (1) the difference of viscosity and particle size between β-carotene solubilized and empty microemulsions; (2) the effects of sunlight and temperature on the stability of β-carotene both in microemulsion and in ethyl butyrate solution. It is shown that in β-carotene loaded systems, the mean particle diameter is 82.13 nm and the size distributions were quite broad (PDI = 0.35). Smaller particles (31.75 nm) and narrower particle size distribution of droplets (PDI = 0.14) were obtained in empty microemulsion. The sizes of droplets of both β-carotene loaded and empty ones get shrunk sharply in the first 3 days, then keep remarkable stability even for a month. β-carotene solubilized in microemulsion is much more stable than that solubilized in ethyl butyrate solution.
Synthesis and Interfacial Activity of Novel Sulfobetaines in Aqueous Solutions
Authors: Staszak Katarzyna , Wieczorek Daria , Zielinski Ryszard 
Published: December 2013

AbstractFourteen new sulfobetaines with N-alkylmorpholinium moiety have been synthesized using correspording N-alkylmorpholines and propanesultone or butanesultone. Their interfacial activities in aqueous solution were studied by equilibrium and dynamic surface tension measurements. Surface tension measurements provide information about the surface excess concentration, the minimum area per surfactant molecule, the critical micellar concentration (CMC) and the standard Gibbs energy of adsorption. The adsorption properties of these compounds significantly depend on the length of alkyl chain (the number of carbons). The lowest value of critical micellar concentration is obtained for the compound with the longest carbon chain and decrease with increasing of chain length of compounds considered. The same tendency is observed for effectiveness of adsorption.
Micellar Catalysis of Chromic Acid Oxidation of Methionine to Industrially Important Methylthiol in Aqueous Media at Room Temperature
Authors: Basu Ankita , Ghosh Sumanta Kr. , Saha Rumpa , Ghosh Aniruddha , Mukherjee Kakali , Saha Bidyut 
Published: December 2013

Abstract
Oxidation of organic molecule by metal is very important. Selective oxidants require non aqueous media, which is toxic and hazardous. L-methionine is oxidized to industrially important methyl thiol in micellar media by chromic acid. The overall reaction follows a first order dependency on substrate and hexavalent chromium and second order dependency on hydrogen ion. Here, reverse micelle formation is observed. TX-100 increases the rate where as SDS retards the rate of oxidation.
Research on Surfactant Flooding in High-temperature and High-salinity Reservoir for Enhanced Oil Recovery
Authors: Zhou Ming , Zhao Jinzhou , Wang Xu , Yang Yan 
Published: December 2013

Abstract
The aim of this work was to research the solution properties of a new surfactant flooding system for high temperature and high salinity reservoir, which include trimeric sulfonate surfactants 1,2,3-tri(2-oxypropyl sulfonation-3-alkylether-propoxyl) propanes (TTSS-n) and anion-nonionic surfactant NPSO [sodium nonyl phenol polyethyleneoxy ether sulfonate, (EO = 10)]. The critical micelle concentrations (CMCs) of five trimeric sulfonate surfactants were smaller than 400 mg L−1. Furthermore, their interfacial tensions (IFTs) could reach an ultralow value with Tazhong 4 oil at lower concentrations. Through optimized formulation, we found that TTSS-12 had better properties and was selected as the major component of the surfactant flooding system. We designed an optimal formulation of the surfactant flooding system with 1 000 mg · L−1 TTSS-12 and 1 000 mg · L−1 NPSO surfactant. The system with a very small surfactant concentration could reach ultralow IFT with Tazhong 4 crude oils at high temperature (110 °C) and high concentration formation brine (112,228.8 mg/L TDS), which proved that the simpler component surfactant had better reservoir compatibility. NPSO could weaken the disadvantage of the surfactant TTSS-12 in oil/water interface. The stability of this surfactant flooding system was evaluated by aging time, static adsorption and chromatographic separation. All experiments showed that it still keeps ultralow IFT in high temperature and high salinity conditions. Coreflooding experimentation showed that average oil recovery reached 9.8 wt% by surfactant flooding, therefore, it is feasible to use as a surfactant flooding system for enhanced oil recovery (EOR).
Effect of Oil/Water Mass Ratios on the Composition and Solubilization of Microemulsion Systems Containing Tween/Alcohol/Alkane/NaCl Solution
Authors: Liao Qiushi , Chai Jinling , Bai Tingting , Wang Dan , Sun Hao , Liu Ning 
Published: December 2013

Abstract
The composition and solubilization ability of microemulsion systems Tween (Tween 20, Tween 60, Tween 80)/1-butanol/decane/7.5 % NaCl solution at various oil/water mass ratios were studied. As oil/water mass ratios (α) increase, the solubility of the alcohol increases, and for the system containing Tween 60 or Tween 80, the mass fractions of the alcohol in the interfacial layer, AS
, increase, whereas for the system containing Tween 20, the mass fractions of the alcohol in the interfacial layer, AS
, decrease. Also, the solubilization ability (SP∗) of the microemulsion systems decreases. The solubilization ability of the microemulsion systems containing different Tween surfactants in descending order is Tween 60 > Tween 80 > Tween 20. The effects of alcohols and alkanes on the composition and solubilization abilities of microemulsion systems Tween/alcohol/alkane/NaCl solution were also investigated.
Foaming Behavior of Dialdehyde Starch Schiff-base Derivatives
Authors: Wang Xiaojuan , Zhang Shufen , Ju Benzhi 
Published: December 2013

Abstract
A foamable dialdehyde starch-aniline Schiff-base (DAS-AN) was synthesized by the reaction of dialdehyde starch (DAS) and oil-soluble aniline in a homogeneous dimethyl sulfoxide system under N2 atmosphere. The DAS-ANs were characterized by gel permeation chromatography (GPC), Fourier-transform infrared spectroscopy (FT-IR) and NMR spectroscopy. Their foaming behavior and surface tension were investigated. Foaming power and stability tests were performed for solutions of DAS-ANs with different degrees of substitutions with aniline (DS
AN) and concentrations. The maximum foaming power was 2.6 times the initial solution volume of the foam test in 450 mg · L–1 CaCO3 aqueous solution. The most stable foams only decreased by 6% in volume in deionized water after 20 min.
Interaction of Cationic CTAB Surfactant with Curcumin, an Anticarcinogenic Drug: Spectroscopic Investigation
Authors: Sharma Rakesh , Jani Dipti 
Published: December 2013

Abstract
Curcumin, the most active polyphenolic constituent of turmeric cucuminoids obtained from rhizome Curcuma longa, holds a high place in ayurvedic medicine but its role in conventional disease management is also established. Unfortunately, the compound has poor aqueous solubility, which results in poor bioavailability following high doses by oral administration. In order to enhance its effectiveness and improve bioavailability, surfactant assemblies as the colloidal drug carriers with desired properties have been largely utilized. The interaction of curcumin with cetyltrimethylammonium bromide (CTAB) surfactant has been investigated by absorption spectroscopy as a function of surfactant concentration in pre-micellar and micellar range at acidic pH of 6.4. The pre-micellar and micellar region of pure CTAB surfactant at acidic pH of 6.4 is examined through tensiometry and conductometry techniques. Spectral data shows that in presence of curcumin at lower CCTAB, the change in absorbance and peak form initially was assigned to attraction of positive head group of CTAB towards the β-diketone group of drug. In micellar region including CMC, the type of interaction corresponds to the attachment of C16 chains of CTAB to nonpolar aryl groups of drug and simultaneously displacement of polar head group from β-diketone group of the drug. Finally at post micellar CCTAB, the encapsulation of the curcumin into micelles, predominantly in intact monomeric form is observed with the sharp peak at λmax = 423 nm.
Parametric Optimization and Thermo-dynamic Studies on the Influence of Electrolytes on Sodium Salicylate in Aqueous Solution
Authors: Pawar Kiran , Desai Meghal A. , Parikh Jigisha 
Published: December 2013

Abstract
Hydrotropes (amphiphiles) start to aggregate at a certain minimum concentration known as the minimum hydrotrope concentration (MHC), above which an appreciable solubilization of insoluble compounds in aqueous solution is observed. However, the MHC values are very high, thus, limiting the applications of hydrotropes. The salts are found to increase the association tendency of hydrotropes and reduction in the MHC. The present study discusses the effect of various electrolytes (Na+, Mg2+ and K+ series) on the behavior of sodium salicylate at different temperatures. Design of experiment was employed to optimize the process parameters. Furthermore, thermodynamic parameters were investigated to observe the stability of the aggregates at higher temperatures.
MonitoringBase Surfactants – A Database Specifically for Storage of Environmental Data on Surfactants in Europe
Authors: Leonards Pim , Eadsforth Charles , Schowanek Diederik 
Published: December 2013

Abstract
A database has been developed in MS Access™ for storage and retrieval of environmental data of surfactants in Europe, as well as general information on major surfactant monitoring programs. The database contains measured concentrations (about 2100 data points) for 8 surfactant groups collected from scientific literature and unpublished reports. The quality of the monitoring data was evaluated and scored using an approach similar to the Klimisch method for judging ecotoxicology and toxicology data. The assignments involve four “Klimisch”-like categories (reliable without restriction, reliable with restriction, not reliable, not assignable), and are based on six key features of a monitoring study, of which three features were found the most important. The proposed evaluation and scoring approach is widely applicable and can easily be applied for other environmental contaminants.
Removal of Heavy Metals from Aqueous Solution by Adsorption on Biomass Based Adsorbent
Authors: Alam Sultan , Bangash Fazlullah Khan , Amin Noor-ul , Azmatullah  
Published: December 2013

AbstractRemoval of heavy metals i.e. Zn2+and Cd2+from aqueous solution by adsorption onto biomass based adsorbent was investigated as a function of time and different concentrations. The sample was characterized by FTIR, EDS, BET surface area and Zeta potential technique, which was reported earlier. Adsorption kinetics of Zn2+and Cd2+was tested by first order kinetics, Elovich and parabolic diffusion kinetic equations which show that the process of adsorption is diffusion controlled process. The rate of adsorption was high at high adsorption temperature. Thermodynamic parameters like ΔH°, ΔS°and ΔG°were calculated from the kinetic data. The negative value of Gibbs free energy (ΔG°) shows the spontaneous nature of the process. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data.
Research of Surface Chemical Properties and Micellization Behavior of Sodium N-Lauroylglycine
Authors: Xu Hujun , Song Chunli , Fang Qing , Huang Yaru , Xu Hao 
Published: December 2013

Abstract
Amphoteric surfactant, sodium N-lauroylglycine, was synthesized and symbolized as SLG. The surface chemical properties and micelle behaviors of SLG in 0–0.5 mol · L−1 aqueous solution of sodium chloride were investigated by surface tension measurements at 298–313 K. The critical micelle concentrations (cmc) of pure surfactant were determined in 0–0.5 mol · L−1 sodium chloride aqueous solution. Fluorescence and micelle aggregation number (N
agg) measurements have been used to investigate the variations of micro-polarity and micellization behavior. The added NaCl has a tendency to increase the attractive interaction between the surfactant molecules in both the micellar phase and the adsorption layer. The Gibbs free energy of micellization (ΔG
m

0
) is negative for all investigated systems, and the thermodynamic parameters of SLG indicate that the micellization of SLG is entropy driven.
Röntgen- und Neutronen — Einblicke in Brennstoffzellen
Authors: Schulze Martin H. , Hartnig Christoph , Manke Ingo , Kupsch Andreas 
Published: December 2013

Kurzfassung
Um die Aufklärung und das Verständnis kritischer Transport- und Alterungsprozesse in Brennstoffzellen voranzutreiben, wurden in einem interdisziplinären Ansatz mathematische, natur- und ingenieurwissenschaftliche Kompetenzen aus sechs Instituten gebündelt. Einen Schwerpunkt bildete dabei der Einsatz zerstörungsfreier bildgebender Verfahren zur in-situ Diagnostik von PEM-Brennstoffzellen unter Betriebsbedingungen. Das vorliegende Heft präsentiert wesentliche Ergebnisse des vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Verbundprojekts „Röntgen- und Neutronenbasierte Untersuchungsmethoden für PEM-Brennstoffzellen“ (RuNPEM, 03SF0324, 2007 bis 2010).
Statistischer Größeneinfluss und Bauteilfestigkeit
Authors: Diemar Andreas , Thumser Rayk , Bergmann Joachim W. 
Published: December 2013

Kurzfassung
Schwingfestigkeitskennwerte können auf Bauteile anderer Form und Größe mit Hilfe des statistischen Größeneinflusses übertragen werden. Zur Charakterisierung der Größe des hochbeanspruchten Bauteilbereiches wird das Spannungsintegral verwendet. Erfolgt die Ermittlung des Spannungsintegrals durch ein Finite Elemente (FE) Programm, ist die notwendige Zuordnung von Oberfläche oder Volumen zu den Stützstellen der Spannung nur durch spezielle FE-Postprozessoren möglich. Diese unterliegen Einschränkungen bezüglich der Wahl des FE-Programms, der Elemente sowie des Integrationsbereiches (Oberfläche, Volumen). Es wird eine Methode vorgestellt, welche die Zuordnung der Wertepaare Oberfläche und Spannung bzw. Volumen und Spannung durch eine geeignete Wahl von Einheitslastfällen ermöglicht. Mit den erhaltenen Wertepaaren erfolgt die numerische Integration. Diese Methode der Spannungsintegralermittlung aus Einheitslastfällen (SPIEL) ist nicht an ein spezielles FE-Programm gebunden.
Laufende Instandhaltung von Schienenfahrzeugen
Authors: Erhard Anton , Heckel Thomas , Schenk Gottfried , Hintze Hartmut 
Published: December 2013

Kurzfassung
Zur Gewährleistung des sicheren Betriebs von Schienenfahrzeugen werden bei der laufenden Instandhaltung die Radsätze (Laufräder und Radsatzwellen) mittels Ultraschall auf Fehlerfreiheit geprüft. Auf Grund der Komplexität der durchzuführenden Prüfungen an der Radscheibe von scheibengebremsten Fahrzeugen ist beim Einsatz konventioneller Techniken eine große Anzahl Ultraschallprüfköpfe erforderlich, deren Reduzierung eine technische Herausforderung darstellt. Auch bei der Prüfung von Radsatzvollwellen sind auf Grund der eingeschränkten Zugänglichkeit unterschiedliche Winkelprüfköpfe erforderlich. Ein Ziel der Untersuchungen bestand darin, die Anzahl der erforderlichen konventionellen Prüfköpfe deutlich zu reduzieren. Dazu kann die Gruppenstrahlertechnik einen Beitrag leisten.
Reflexionsverhalten in fokussierten Schallfeldern
Authors: Boehm Rainer , Erhard Anton , Rehfeldt Thomas 
Published: December 2013

Kurzfassung
Angeregt durch experimentelle Arbeiten zur hochauflösenden Ultraschallprüfung mit fokussierenden Prüfköpfen wird mit Hilfe von Modellrechnungen der Einfluss verschiedener Schallfeld- und Reflektorparameter auf die Echohöhe untersucht. Von besonderem Interesse ist dabei das Verhalten typischer Testreflektoren wie der Kreisscheibenreflektor und die Querbohrung in „verformten“ Schallfeldern, die durch Bauteilkrümmungen und Fokussierung entstehen können. Für solche Fälle lassen sich Abstandskurven (DAC) für verschiedene Reflektortypen rechnerisch erstellen und der experimentelle Aufwand erheblich reduzieren. Ein deutlicher Fortschritt wurde durch die Weiterentwicklung des Schallfeldmodells erreicht, das insbesondere für die Entwicklung neuer Typen von Gruppenstrahlerprüfköpfen unverzichtbar ist. Die Gültigkeit des Modells wird durch bisherige Messergebnisse bestätigt.