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PL
Przedstawiono wyniki badań dotyczących wydzielania fioletu krystalicznego z wodnych roztworów koloidalnych techniką temperatury zmętnienia (CPE). W pracy wykorzystywano niejonowy oraz amfoteryczny związek powierzchniowo czynny. Zaobserwowano, iż najlepszą separację uzyskuje się z roztworu zawierającego mieszaninę surfaktantów z dodatkiem 1 M NaCl, natomiast najsłabszy wynik osiągnięto w przypadku roztworu zawierającego jedynie niejonowy związek powierzchniowo czynny.
EN
Crystal violet was recovered from aq. 2-5 mg/l. solns. by cloud-p. extn. with oxyethylenated(n = 9) methyl dodecanoate as nonionic and cocamidopropyl betaine as zwitterionic surfactant. The dye was recovered (2500 rpm) in 92.1%.from the system contg. dodecanoate 2.5, betaine 0. 5%, and NaCl 1 mol/l.; heating time 6 hrs, The formation of the dye-contg. surfactant phase was incomplete. The water phase contained surfactant-rich agglomerates. NaCl reduced the time of formation and the size of the sepg. agglomerates. In solns. contg. the two surfactants, betaine concn. (should not exceed 0.5%) controlled the cloud p. In aq. 01-5% betaine solns., no cloud p. occurred over 0-100°C.
EN
Ultrasonic measurements of the velocity and absorption coefficient, α/f2, of aqueous solutions of β-cyclodextrin with alkyl pyridinium bromides CnH2n+1C5H4NBr (n = 8, 10, 12), were carried out at the following temperatures: 288.2 K, 298.2 K, 308.2 K and 318.2 K, and frequency range from 1 MHz to 150 MHz. Concentration of the both components equaled 0.01 M. The occurrence of two ultrasonic relaxation processes has been reported. Thermodynamic and kinetic parameters related to these processes have been calculated. The obtained results have been compared with data published previously for α-cyclodextrin systems.
EN
In second part of this work, velocity and absorption measurements of ultrasonic waves in aqueous solutions of ß-cyclodextrin containing different sodium alkyl sulfates are reported. One or two relaxation processes for these solutions have been established. Thermodynamic and kinetic parameters related to these processes have been calculated. The results have been compared with those obtained for solutions of ?-cyclodextrin and presented in Part 1 of this paper. Explanation of the origins of these processes has been proposed.
EN
In this part, the velocity and absorption measurements of ultrasonic waves in aqueous solutions of [alpha]-cyclodextrin containing different sodium alkyl sulfates are reported. One or two relaxation processes for these solutions have been established. Thermodynamic and kinetic parameters related to these processes have been calculated. In the second part, experimental results for ß-cyclodextrin will be reported and compared with those presented here.
EN
The surface properties of sodium dodecyl sulfonate (SDSn), dodecyl-b-D-glucoside (DG), dodecyltrihydroxyethylammonium bro mide (DTEAB) and sodium dodecyl sul fate (SDS) and their mixtures: SDSn/SDS, SDSn/DG and SDSn/DTEAB were studied. The miscibility and the composition of the mixed monolayers and micelles as well as the interactions between their components were analyzed with the Motomura theory. It was found that among the investigated mixed systems the best surface properties reveal the anionic-cationic mixtures. Moreover, the investigated systems mix nonideally both in the monolayers and micelles. The magnitude of the deviations from ideal behaviour increases in the order: an ionic/an ionic < an ionic/nonionic << an ionic/cationic. Both the mixed monolayers and mi celles formed from SDSn/SDS and SDSn/DG mix tures are richer, as compared to the mixed solutions, in the more surface-active component, while the mixed monolayers and micelles formed from cationic/anionic mixtures (SDSn/DTEAB) possess more symmetrical composition than the mixed solution. As it was found the interactions between molecules both in the mixed monolayers and micelles are more attractive or less repulsive as compared to those in respective one-component monolayers and micelles and the strength of these interactions increases in the order: SDSn/SDS < SDSn/DG < SDSn/DTEAB.
EN
This article aims to investigate in detail to what extent surfactants affect the determination of cadmium by anodic stripping voltammetry. In recent years, the production and use of surfactants have been steadily increasing, so that their concentration in environmental water samples is rising. At the same time, it is known that organic compounds, such as surfactants, often hinder the voltammetric determination of trace elements by stripping. Non-ionic (Triton X-100, Brij 35, Tween 20, Tween 60, Tween 80), cationic (CTAB, CTAC, DTAB, HPC) and anionic (DSS, SDS) compounds were selected to investigate the effect of surfactants on the voltammetric signal of cadmium. At the same time, the extent to which the addition of Amberlite resins to the analysed solution eliminates the interfering effect of surfactants was tested. Three types of Amberlite resins XAD-2, XAD-7 and XAD-16 were selected for the study and the ratio of resin weight to solution volume was determined. Finally, the determination of cadmium in surfactant-enriched environmental samples was carried out. The recoveries obtained between 95.5 and 107%, with RSD between 3.4 and 6.2%, confirm the validity and correctness of the proposed procedure All measurements were carried out by anodic stripping voltammetry using a CNTs/SGC electrode modified with a bismuth film as the working electrode.
EN
Some surfactants widely used as additives in food, pharmaceuticals, and cosmetic formulations are susceptible to peroxidation resulting in accumulation of hydroperoxides (HP). Our investigation was aimed to study the possible influence of different surfactants on the proportionality and reproducibility of the ferrous oxidation-xylenol orange method developed originally for the determination of hydroperoxides. We also attempted to apply this method to determine hydroperoxides produced radiolytically in surfactant molecules. From our preliminary studies we conclude that the method can be applied for determination of hydroperoxides in systems containing non-ionic or anionic surfactants provided careful calibration is performed for each surfactant.
EN
The objective of this paper was to determine the Critical Coalescence Concentration (CCC) of surfactants such as N(dodecyloxycarboxymethyl) N,N,N(trimethylammonium) bromide (DMGM-12), N-[2-(dodecyoxycarboxy)ethyl] N,N,N-(trimethylammonium) bromide (DMALM-12) and N-[3-(dodecanoyloxycarboxy)prophyl] N,N,N-(trimethylammonium) bromide (DMPM-11). The surfactants used represent quaternary ammonium compounds containing a hydrophobic moiety with an ester group (commonly known as “esterquats”). The CCC value was determined by analysis of the relationship between concentration of surfactant and average air bubble diameter. The values of the critical coalescence concentration (CCC) were estimated using a graphical method.
PL
Celem pracy było wyznaczenie krytycznego stężenia koalescencji CCC surfaktantów, takich jak: bromek N-(dodecylooksykarboksymetylo)-N,N,N-trimetyloamoniowy (DMGM-12), bromek N-[2-(dodecylooksykarboksy)etylo]-N,N,N-trimetyloamoniowy (DMALM-12) oraz bromek N-[3-(dodekanoylooksy)propylo]-N,N,N-trimetyloamoniowy (DMPM-11). Zastosowane odczynniki to czwartorzędowe związki amoniowe, zawierające hydrofobową grupę zawierającą grupę estrową (powszechnie nazywane, jako „esterquaty”). Określenie wartości krytycznego stężenia polegało na przeanalizowaniu zależności stężenia badanego surfaktantu od średniej średnicy pęcherzyka powietrza. Wartości krytycznego stężenia koalescencji (CCC) określono za pomocą metody graficznej.
EN
This work presents the application of the free solution electrophoresis method (FSE) in the metallic / semiconductive (M/S) separation process of the surfactant functionalized single-walled carbon nanotubes (SWCNTs). The SWCNTs synthesized via laser ablation were purified through high vacuum annealing and subsequent refluxing processes in aqua regia solution. The purified and annealed material was divided into six batches. First three batches were dispersed in anionic surfactants: sodium dodecyl sulfate (SDS), sodium cholate (SC) and sodium deoxycholate (DOC). The next three batches were dispersed in cationic surfactants: cetrimonium bromide (CTAB), benzalkonium chloride (BKC) and cetylpyridinium chloride (CPC). All the prepared SWCNTs samples were subjected to FSE separation process. The fractionated samples were recovered from control and electrode areas and annealed in order to remove the adsorbed surfactants on carbon nanotubes (CNTs) surface. The changes of the van Hove singularities (vHS) present in SWCNTs spectra were investigated via UV-Vis-NIR optical absorption spectroscopy (OAS).
EN
Due to the lower energy consumption and waste production compared to traditional methods, the environmental bioremediation methods based on natural processes have been gradually becoming more prevalent in environmental engineering. Biological methods are used in waste management, wastewater treatment, gas treatment or soil remediation. For the low solubility of some pollutants and lower bioavailability, the use of biological methods may be hampered. This problem might be mitigated with the use of surfactants. This paper presents the results of studies regarding the effect of dosing a selected surfactant from the Tween group (Tween 20) on the efficiency of toluene elimination from the air by biofiltration. The obtained maximum biofiltration rate was 21.2 g/m3/h and 19.8 g/m3/h for the control bed and for the bed to which the Tween 20 solution was dosed, respectively. The effect of Tween was neutral (the effectiveness of toluene removal was insignificantly comparable to the effectiveness of the control series), it did not affect the effectiveness or limited the development of the biofilter microflora.
PL
Przedstawiono związki makrocykliczne (etery koronowe, kaliksareny i acykliczne polietery) jako nowego typu surfaktanty w procesach selektywnego wydzielania (ekstrakcja ciecz–ciecz, transport przez ciekłe membrany i flotacja jonów). Omówiono konkurencyjną flotację izotopów Cs-137, Sr-90 i Ba-133 jonizowalnymi eterami lariatowymi oraz Zn(II) i Cd(II) jonizowalnymi eterami koronowymi i eterami, ekstrakcję ciecz–ciecz kationów Cs⁺, Co²⁺ i Sr²⁺ za pomocą niejonizowalnych eterów koronowych w obecności kwasu 5,8-dinonylonaftalenosulfonowego (DNNS) i ekstrakcję ciecz–ciecz kationów litowców i berylowców za pomocą jonizowalnych dibenzo eterów lariatowych i acyklicznych polieterów, a także konkurencyjny transport kationów litowców i berylowców w procesach permeacji przez ciekłe membrany za pomocą związków makrocyklicznych.
EN
A review with 44 refs. covering crown ethers, calixarenes, calyx-crown-arenes, and acyclic polyethers as surfactants in solvent extn., transport across liq. membranes, and ion flotation, esp. competitive ion flotation of Zn(II) and Cd(II); and Cs-137, Sr-90, and Ba-133 with ionizable lariat ethers; solvent extn. of Li and Be groups cations with ionizable dibenzo crown ethers and acyclic polyethers; calixarenes as ion carriers in liq. membrane transport; and competitive transport of Li and Be groups cations in permeation through liq. membranes.
EN
PLA/nanofibrillar cellulose (NFC) composite films were produced by solution casting. Before use, the cellulose fibers were modified with various types of surface active agents – cationic, anionic and non-ionic surfactants. The structure and morphology of samples of the cellulose fillers and composite films with polymer were analyzed by means of scanning electron microscopy and PXRD diffraction. Thermal parameters of the composite films were characterized by differential scanning calorimetry and thermogravimetric analysis. The tensile strength and elongation at break of the films were evaluated in mechanical tests. The ability to disintegrate of all PLA/NFC composites under composting conditions was also determined and compared.
EN
The effect of anionic, non-ionic and cationic surfactants in solution on electrochemical responses of poly(pyrrole) films were studies. It was found that surfactants present in solution in mmol/dm3 concentrations practically do not affect voltammetric behavior of cation-exchanging poly(pyrrole) films doped with hexacyanoferrate ions. In contrary, for anion-exchanging poly(pyrrole) films doped with chlorides, PPyCl, charge transfer process observed under conditions of voltammetric experiment was significantly, irreversibly, inhibited by surfactants in solution in _mol/dm3 concentration; regardless the charge of surfactant molecule. As shown by AC voltammetric experiments the choice of frequency (time) scale can be used to amplify or suppress the conducting polymer sensitivity of the current response of polymer for surfactants. These effect are important from the analytical point of view. For high frequencies or under potentiometric conditions surfactants do not interfere with ions concentration determination. On the other hand, for low frequencies surfactants interactions with PPyCl membrane give rise to analytically useful signal. The linear dependencies of current on logarithm of surfactant concentration were obtained within the concentration range at least from 10-7 to 10-4 mol/dm3.
EN
Electrochemical properties of anion- and cation-exchanging conducting polymer: poly(3,4-ethylenedioxythiophene) films, doped by nitrate (PEDOT(NO3) or poly(4-styrenesulfonate) ions (PEDOT(PSS)), were stud ied in NaCl so lu tions con tain ing surfactants: an ionic (sodium dodecylbenzenesulfonate, NaDBS), cationic (hexa decyl - trimethylammonium chlo ride, RNCl) and non-ionic (Triton X 100). Voltammetric experiments revealed significant influence of surfactant only for PEDOT(NO3) in the presence of NaDBS, resulting from inter actions between anion-exchanging polymer and anionic surfactant. Impedance spectroscopy studies exhibited inhib iting influence of surfactant ions reversibly retained on the polymer/solution inter face on the rate of interfacial ion transfer, with no significant decrease of charge storing capability (redox capacitance). The influence of surfactants on analytical applicability of PEDOT as a receptor membrane for potentiometric ion sensors was discussed.
EN
The static magnetic field MF (0.44 T) effects on the adsorption of three surfactants: cationic bromide (DTAB) and hexadecyltrimethylammonium bromide (CTAB), and anionic sodium dodecylsulfate (SDS) from their 10-3 M solutions were studied on bare and low-temperature air plasma treated glass plates. The surface properties of the adsorbed surfactants layers were determined via the water advancing and receding contact angles measurements and then calculation of the apparent surface free energy. An optical profilometer was used to determine the structure and topography of the adsorbed layers. The DTAB and SDS concentrations were below their critical micelle concentration and that of CTAB very close to its cmc. The results showed that in the case of DTAB solution (much below its cmc) a small decrease in the contact angle appeared while in CTAB (close to its cmc) an increase in the contact angle value was observed if adsorbed in the MF presence. Quite good reproducibility of the contact angle values was obtained. This was not the case for the SDS solution where the contact angle values were scattered. The reason was that the anionic surfactant did not adsorb homogeneously on the negatively charged glass surface. The contact angles and the calculated values of the work of water spreading clearly show that MF influences the structure of the surfactant adsorbed layer which was also supported by the optical profilometry images.
EN
Surfactants are various types of chemical compounds that are present in almost every aspect of our life. They are used in many branches of industry, especially in food, cosmetics, pharmaceuticals and even in confectionery. They are considered one of the best solutions for oil residues, soil bioremediation and dealing with PAHs contaminations. Their versatility comes from their amphiphilic build – one part of the compound has hydrophilic properties (head), the other has hydrophobic properties (tail). This fact causes surfactants affinity both to polar and nonpolar compounds. Some of the classical surfactants still can affect fauna and flora by accumulating in ground waters or simply by causing allergies. In that case, many companies decide to limit their surfactant usage and reach for substances present in nature which have very similar, if not better, properties. Biosurfactants are surface active agents produced mainly by microorganisms such as bacteria, fungi and yeasts. There are many papers related to different properties (CMC, aggregation number, surface excess concentration) of various types of surfactants. However, it is difficult to find papers describing the same properties for different surfactants. In this study, adsorption effectiveness and adsorption efficiency at the water-air interface of chosen surfactants: sodium dodecylsulfate (SDDS), cationic: cetyltrimetylammonium bromide (CTAB), nonionic: Triton X-100 (TX-100) and biosurfactants: surfactin (SF) and monorhamnolipid (RL)  has been compared. Both efficiency and effectivenes decide about the practical surfactants application.
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