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The authors discuss the principles of continuous dyeing from solvents and describe methods for the continuous dyeing and fixing of disperse dyes on polyester Fixation with solvent steam is compared with conventional methods. [ABSTRACT FROM AUTHOR]

The permeability of excised human skin to dimethyl sulphoxide and the effects of this solvent on water permeability, are described. The results of measurements of the electrical impedance of excised human skin both before and after chemical and heat treatments are also given. Stratum corneum is shown to undergo irreversible structural changes when heated above 65°C. or incubated in aqueous media at pH < 3 or > 9. Simultaneous measurements of water permeability and electrical impedance of skin samples subjected to treatments with dimethyl sulphoxide, detergents and surfactants show that there is a good correlation (coefficient - 0.78) between the two quantities. Some organic solvents including aliphatic acids, bases, and neutral compounds are shown to produce large changes in electrical impedance, and hence, it is inferred, in water permeability. It is suggested that these changes are due to solution of skin components, loosening of the skin structure, and hence swelling and hydration of the skin. The solvent induced changes in water permeability provide an explanation for the accelerating effect of the solvents on the penetration rates of topically applied drugs. [ABSTRACT FROM AUTHOR]

The Fe-HClO4 reaction for the assay of IAA has been extended to organic solvents, resulting in increased sensitivity and utility of the reaction. Direct colorimetric determinations of IAA in plant preparations are demonstrated to he inaccurate. However, by coupling the colorimetric assay with chromatography and elution. it is shown that IAA may be resolved from mixtures and quantitatively estimated. The method gives a less equivocal measure of IAA in plant extracts and enzymatic preparations than does direct colorimetry. [ABSTRACT FROM AUTHOR]

There is no dramatic evidence as yet that the use of solvents is increasing at a rate sufficient to justify the prominence they have been assigned. With this thought in mind, the author highlights the broad benefits, drawbacks and limitations of using nonaqueous solvents in processing, and assesses the specific functions they [night realistically be expected to play m light of other major changes which are occurring in the industry. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a single-step synthesis route to prepare lauryl gallate capped TiO2 nanoparticles has been established. Powder X-Ray diffraction analysis shows anatase as the predominant inorganic phase. UV–vis and FT-IR spectroscopy characterization denotes that lauryl gallate molecules are covalently linked to the particulate titania core through the enediolate group. The as prepared powder is easily dispersable in common organic solvents, such as tetrahydrofurane, methylethylketone and n-butanol, showing good stability under ambient atmosphere. This solution processable precursor facilitates thin film deposition on glass substrates. The capping gallate derivative also facilitates preparing translucent TiO2-polystyrene composites. [Copyright &y& Elsevier]

The results of the calorimetric studies of the enthalpies of mixing of some ionic liquids, 1-butyl-3-methylimidazolium chloride and acetate, with water, pentanol, dimethyl sulfoxide and dimethylformamide are presented. Protic solvents interact with the ionic liquid anion, wheras aprotic, with the cation. The mixing enthalpy depends on the dissociation degree of the ionic liquid. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we report on the crystal growth and characterization of 9,10-diphenylanthracene. Crystals of 9,10-diphenylanthracene (DPA) were grown by the solution growth technique as well as the vertical Bridgman method. In case of the solution growth technique, several organic solvents were investigated including heptane, cyclohexane, toluene, and p-xylene. The largest crystals of the highest quality were obtained from toluene and xylene. In the case of vertical Bridgman, evacuated silica ampoules were used to grow large single crystals of DPA. Crystals grown by this method exhibit excellent scintillation properties. Radioluminescence spectra of DPA crystals exhibit a broad emission band peaking at 475nm. DPA crystals show high light yields of up to 20,000ph/MeV and a fast scintillation decay of less than 20ns. Fast neutron detection was achieved using a 252Cf source. [Copyright &y& Elsevier]

Abstract: The ionic liquid (IL) trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl phosphinate ([P6,6,6,14][( i C8)2PO2]) has been shown to passivate magnesium alloy AZ31 at anodic potentials within the IL environment. In this study, [P6,6,6,14][( i C8)2PO2] IL was diluted in organic solvent acetonitrile to concentrations of 0.1 and 0.01M. Cyclic voltammetry (CV) at anodic potentials from open circuit potential (OCP) appeared to passivate the surface in both solutions to the same degree. Thicknesses of 80 and 29nm were determined for films formed under anodising conditions in neat IL and 0.1M IL in acetonitrile respectively. The results indicate that despite dilution in acetonitrile the electrochemical behaviour of the IL is essentially unchanged. However, the effect of dilution changes the process of film formation during anodising to 18V, resulting in different film thicknesses. [Copyright &y& Elsevier]

Abstract: The solubility of 3-aminopyridine in (ethanol+toluene) mixed solvents has been measured between 283.15 and 323.15K at intervals of 5.00K by a static analytical method. Nonlinear dependences were found for the variation of solubility with temperature. The nonlinear van’t Hoff equation was proposed for correlating the experimental data. The apparent molar enthalpies of 3-aminopyridine in the solvent mixtures were determined from the temperature dependence of the solubilities. The values for the apparent Gibbs energy and the apparent entropy of solution are calculated. [Copyright &y& Elsevier]

The article focuses on the complexes of N-(1-silatranylmethyl) derivatives of cyclic imides with CoC. The complexes obtained are bright-blue powders readily soluble in polar organic solvents. The possible centers of complex formation in these can be the oxygen atoms of the silatrane skeleton or the carbonyl groups of the heterocycles.

A ditopic melamine bearing perylene bisimides with swallow-tail alkyl chains can be dissolved in organic solvents by mixing with complementary hydrogen-bonding barbiturate or cyanurate, forming solution processable supramolecular assemblies. Upon spin-coating the assemblies, highly organized lamellar architectures are formed with thermal annealing, which act as electron transporting layers in organic field effect transistors. [ABSTRACT FROM AUTHOR]

An understanding of the activity of a solute in solution is vital for utilising the full potential of a reactive species. In this work we determine the activity of metal salts in a variety of ionic liquids. Some solutions behave like classical non-polar solvents whereas other are practically ideal solutions up to 1 mol kg−1which allows standard redox potentials to be determined. [ABSTRACT FROM AUTHOR]

Abstract: Calorimetric measurements have been carried out at 298.15K in aqueous solutions of glycylglycylglycine containing formamide, N-methylformamide, N,N-dimethylformamide and N,N-diethylformamide at concentrations of amides as co-solvents up to 0.4mole fractions. The results obtained have been used to calculate the standard enthalpies of solution (Δsol H°) and transfer (Δtr H°) of the glycylglycylglycine from water into the mixtures as well as enthalpy coefficients of pair-wise interaction (h xy ) of the solute with amide in aqueous media. The h xy values were correlated with the properties of organic solvents using Kamlet–Taft equation. The results of the calorimetric measurements have been discussed with regard to the intermolecular interactions occurring in these systems. [Copyright &y& Elsevier]

CO2can be used to separate surfactant and organic solvent completely in various surfactant/solvent solutions without contaminating the surfactants and solvents. We believe that the simple, efficient, and greener method has wide applications. [ABSTRACT FROM AUTHOR]

Abstract: Warfarin is an important oral anticoagulant drug that demonstrates a molecular-environment dependent structural diversity. Previous investigations of warfarin’s ensemble of isomers in organic solvent-based environments have pointed to the importance of the closed-ring cyclic hemiketal form of the drug in non-polar environments, e.g. the interior of proteins, enzymes and biomembranes. Detection of the presence of these isomers in polar environments has not yet been reported. Here, we demonstrate the presence of the cyclic hemiketal structural form of warfarin under aqueous conditions. This finding underscores the importance considering all structural isomers of this drug when making predictions on warfarin’s bioavailability. [Copyright &y& Elsevier]

Ultrafast carrier dynamics and saturable absorption of few-layered graphene oxide, well-dispersed in organic solvent, are studied using femtosecond pump-probe and Z-scan techniques. The results demonstrate that few-layered graphene oxide has a fast energy relaxation of hot carriers and strong saturable absorption, which is comparable with that of reduced graphene oxide. Fast carrier relaxation combined with well solution processing capability arises from the large fraction of sp2 carbon atom inside the few-layered graphene oxide sheet together with oxidation mainly existing at the edge areas. This superiority of few-layered graphene oxide will facilitate potential applications of graphene for ultrafast photonics. [ABSTRACT FROM AUTHOR]

An eco-friendly efficient synthesis of symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles is described through the reaction of aromatic hydrazides with aryl aldehydes obtained by grinding them in the presence of catalytic amounts of molecular iodine in a mortar in a single step. The present method avoids the isolation of N-acyl hydrazones prior to their oxidative cyclization and avoids the use of organic solvents at any stage of the reaction. [ABSTRACT FROM AUTHOR]

Certain protic ionic liquids (PILs) were found to dissolve zein, which is one of the industrially important natural protein polymers. We prepared two PILsN-(2-hydroxyethyl) ammonium formate (HEAF) and N-(2-hydroxyethyl) ammonium acetate (HEAA)and their ability to dissolve zein was investigated. Up to 70% zein solution may be prepared, but it was difficult to process, because of high viscosity. Zein solutions with 5%−20% concentration were easily prepared by heating at 95 °C or higher with aid of microwave treatment, even in the presence of small amounts of water. A two-step microwave-only heating process can also be useful in preparing solutions with up to 20% zein. No significant disparity was found between HEAF and HEAA, in terms of dissolving zein. Both HEAF and HEAA could be economically viable and environmentally benign solvents, not only over conventional organic solvent systems, but also over other imidazolinium-type ionic liquids, such as 1-butyl-3-methylimidazolinium, which had been suggested as a solvent for zein. [ABSTRACT FROM AUTHOR]

Abstract: Here we present the special self-assembly properties of the amphiphilic macromolecules made from G1 PAMAM dendrimers partially modified with cholic acid. These cholic acid-derived macromolecules can self-assemble in both apolar and polar solvents. The aggregates of these macromolecules in toluene can partially extract hydrophilic molecules from water to toluene. The macromolecules in aqueous solutions can form multiple morphological aggregates which are nanoparticles below pH 10.0 and microparticles above pH 13.0. The nanoparticles release methotrexate, an anticancer drug, in a pH-dependent manner. The results indicate that the solvent-controlled self-assemblies may make the macromolecules good candidates for pH-controlled drug release carriers with good cell membrane permeability. This macromolecule may have potential applications in intracellular drug delivery systems. [ABSTRACT FROM AUTHOR]

The article evaluates the topochemical reaction of germatranol with citric acid by using X-ray diffraction method. The method shows that the initial compounds enter into a topochemical reaction to form complex III that is incapable of forming a stable liquid phase on heating and soluble in water and insoluble in organic solvents. It notes that the topochemical reaction between germatranol and citric acid can be significant as a route germatranol citrate.

A simple acid-resistanthydrophobic tag, which can be removed rapidly in a single-step procedure after overall peptide synthesis, has been developed to accomplish practical solution-phase synthesis of a 15-mer antagonistic peptide of TNF-α (A-TNF-α). Hydrophobically tagged peptides can be separated as precipitates at each step by addition of a polar organic solvent. [ABSTRACT FROM AUTHOR]

Applying an additional hydrostatic pressure, which is determined by the difference (Bi –Bj) in Tait''s equation coefficients, to liquids (Sj) with a higher compressibility coefficient equalizes the compressibility of all the liquids studied (Si). The correlation obtained makes it possible to predict the compression curve of any liquid over a wide pressure range based on the value of βT determined at ambient pressure. [Copyright &y& Elsevier]

Abstract: The electrokinetic potential of titania was studied as a function of concentration of SDS, DOSS and CTMABr in a series of solvents. In water and 50–50 water–methanol mixture, which are the most polar studied solvents, the organic ion is adsorbed on titania and the small inorganic ion remains in solution. In hexane the adsorption behavior is reversed, that is, the organic ion remains in solution and the small inorganic ion is adsorbed on titania. The borderline between these two types of behavior corresponds to solvent dielectric constant of about 25. In solvents, which have a dielectric constant in this range (methanol and 1-propanol) the adsorption preferences vary from one surfactant to another. The affinities of the organic ion and of the small inorganic ion to the surface are often similar, and then none of the ionic components is preferentially adsorbed, and the electrokinetic potential is not affected. In such cases, ionic surfactants are not suitable as agents for regulation of zeta potential. [Copyright &y& Elsevier]

Abstract: The enthalpies of solution of cyclic ethers: 1,4-dioxane, 12-crown-4 and 18-crown-6 in {(1− x)AN+ xH2O} have been measured over the whole mole fraction range at T = 298.15K. Based on the results obtained, the effects of base–acid properties of mixed solvent and the number of –CH2CH2– groups in cyclic ethers molecules on the solution enthalpy of cyclic ethers in {(1− x)AN+ xH2O} have been analyzed. [Copyright &y& Elsevier]

The solubility of 3-chlorophthalic anhydride and 4-chlorophthalic anhydride in ethyl acetate, acetone, and 1,4-dioxane and the solubility of 3-chlorophthalic acid and 4-chlorophthalic acid in water were measured using Schreinemaker’s wet residue method at temperatures ranging from (283.15 to 333.15) K at atmospheric pressure. Results of these measurements were correlated with the modified Apelblat equation. [ABSTRACT FROM AUTHOR]

The solubilities of cloxacillin sodium in binary butyl acetate + methanol and ethyl acetate + methanol solvent mixtures were measured at temperatures ranging from (283.15 to 298.15) K. The experimental data can be well correlated by the CNIBS/Redlich−Kister model. The results show that the solubility of cloxacillin sodium increases with increasing temperature and mole fraction of methanol in these two binary mixed solvents. [ABSTRACT FROM AUTHOR]

Abstract: 1-Butyl-3-methylpyridinium tribromide, [BMPy]Br3 proves to be a highly efficient, regioselective reagent/solvent for nuclear bromination of various anilines and phenols. The synthesis and characterization of the room temperature ionic liquid [BMPy]Br3 (2) is described. The bromination was carried out in the absence of organic solvents and in most cases the only extraction solvent needed was water. The spent 1-butyl-3-methylpyridinium bromide (1) was easily recycled. [Copyright &y& Elsevier]

Ethyl L-lactate can be tuned with a cosolvent to create polarity conditions ideal for synthesizing aryl aldimines that crystallize directly out of solution within minutes under ambient conditions in excellent yields and requiring no further purification. [ABSTRACT FROM AUTHOR]

Polymer microarrays, consisting of either discrete features or a matrix of inter-crossed lines were directly fabricated in situby inkjet printing individual monomers and initiator solutions in organic solvents through a film of oil, thereby allowing the rapid generation of a broad range of co-polymers, while solving the problem of selective monomer evaporation. [ABSTRACT FROM AUTHOR]

Aqueous dispersed graphene was successfully prepared viausing 7,7,8,8-tetracyanoquinodimethane (TCNQ) anion as a stabilizer and expanded graphite as a starting material, which could provide a facile route to produce high quality water-soluble and organic solvent-soluble graphene sheets for various applications. [ABSTRACT FROM AUTHOR]

We present a procedure to reconfigure microring resonators based on liquid surface adhesion. Droplets of organic solvents were deposited over Si3N4/SiO2 strip- and slot-waveguide ring resonators, and the transmission spectra were measured several hours after the evaporation of the droplets at room temperature. Our measurements show that the optical properties of the microrings are significantly modified by liquid adhered to the waveguides, persisting even 96 h after bulk evaporation. Liquid-solid interfacial forces slow down liquid evaporation at the nanoscale, enabling permanent photonic configurations. Rewriteability is achieved by removing the adhered liquid with heat. [ABSTRACT FROM AUTHOR]

Pseudomonas putida dried in the presence of hydroxyectoine or trehalose can withstand exposure to organic solvents and therefore can be encapsulated inside plastics such as polystyrene. Here we show that P. putida in a plastic-encapsulated dried tablet exhibits remarkable tolerance to chemical stress, comparable to that of spores of Bacillus subtilis. [ABSTRACT FROM AUTHOR]

Mixtures of an appropriate carboxylic acid and n-butylstannoic acid constitute modular gelation systems, in which the formation of a well-defined ‘tin-drum’ nanocluster subsequently underpins the hierarchical assembly of nanostructured fibres, which form self-supporting gel-phase networks in organic solvents. [ABSTRACT FROM AUTHOR]

The solubilities of 2-(4-ethylbenzoyl)benzoic acid in N,N-dimethylformamide, N-methyl-2-pyrrolidone, methanol, ethanol, 1-propanol, 2-propanol, tetrahydrofuran, benzene, 1,4-dioxane, acetone, and ethyl formate were measured using a synthetic method at temperatures in the range from (279.55 to 343.15) K under atmospheric pressure. The laser-monitoring observation technique was used to determine the dissolution of the solid phase in a solid liquid mixture. The solubility of 2-(4-ethylbenzoyl)benzoic acid in different solvents increased as the temperature increased. Measured solubility values were well correlated as a function of temperature by the modified Apelblat equation. [ABSTRACT FROM AUTHOR]

The oxo-bridged dimer [Mo2O4(μ2-O)Cl2(pzH)4] (1; pzH = pyrazole) exhibits unusually high activity in the liquid-phase catalytic epoxidation of the cyclic olefins cyclooctene and (R)-(+)-limonene under mild conditions and in the absence of additional organic solvents, using tert-butyl hydroperoxide as the oxidant. The complex is stable under the reaction conditions and can be used in further catalytic runs without significant loss of performance. An X-ray crystallographic investigation reveals that 1 has an unprecedented and extremely rare all-cis configuration at each of the MoO2-(μ2-O)Cl(pzH)2 cores, which can be understood by considering supramolecular contacts and geometric factors. [ABSTRACT FROM AUTHOR]

Antipyrine and its benzenesulfonate were iodinated by solid-state mechanical activation (in the absence of solvent) under the action of iodine, iodine chloride, Me4N+ICl2 −, and Et4N+ICl2 − with the formation of 4-iodoantipyrine. The proposed process does not require organic solvents and meets all Green Chemistry demands. The best results were achieved with the use of tetraalkylammonium salts Me4N+ICl2 − and Et4N+ICl2 −. [ABSTRACT FROM AUTHOR]

The solubility of 4-(3,4-dichlorophenyl)-1-tetralone in methanol, ethanol, 2-propanol, acetone, toluene, N,N-dimethylformamide, and tetrahydrofuran were measured using a laser technique in the temperature range from (278.15 to 323.15) K. The results were correlated with a semiempirical equation, which can be used as a useful model in the production process of 4-(3,4-dichlorophenyl)- 1-tetralone and sertraline hydrochloride. [ABSTRACT FROM AUTHOR]

Nine new double-salt compounds have been prepared and six crystal structures are reported that demonstrate a general metathesis route to double-salt compounds with metallophilic interactions. The compounds contain [Pt(terpy)X]+ or [Au(bpy)X2]+ cations, AuIII or AuI anions such as [AuBr4]- or [AuCI2]-, and are prepared in water and recrystallized from organic solvents. In all crystallo-graphically characterized cases, there exist metallophilic interactions between cations and anions, demonstrating the power of this general route. In most cases, there exists an unbroken chain of metallophilic interactions through the crystal, forming single-atom-wide wires. [ABSTRACT FROM AUTHOR]

Abstract: Dimerization of styrene was investigated in ionic liquids and organic solvents with the catalysis of several palladium–Lewis acids catalyst systems. Pd(OAc)2/Cu(OTf)2 and Pd(OAc)2/In(OTf)3 in 1-butyl-3-methylimidazolium hexafluorophosphate were found to be effective catalyst systems towards the dimerization of styrene to 1,3-diphenyl-1-butene at room temperature. [Copyright &y& Elsevier]

Abstract: Eightfold higher yields and three times faster reaction rates were achieved by means of using a mixture solvent system composed of 90% acetone and 10% [BMIM]BF4 in the lipase-catalyzed regioselective synthesis of polymerizable ester of nucleoside drugs. [Copyright &y& Elsevier]

To facilitate industrial applications, as well as for environmental and health purposes, there is a need to find less hazardous solvents for processing the photoactive layer of organic solar cells. As there are vast amounts of possibilities to combine organic solvents and solutes, it is of high importance to find paths to discriminate among the solution chemistry possibilities on a theoretical basis. Using Hansen solubility parameters (HSP) offers such a path. We report on some examples of solvent blends that have been found by modelling HSP for an electron donor polymer (TQ1) and an electron acceptor polymer (N2200) to match solvent blends of less hazardous solvents than those commonly used. After the theoretical screening procedure, solubility tests were performed to determine the HSP parameters relevant for the TQ1:N2200 pair in the calculated solvent blends. Finally, thin solid films were prepared by spin-coating from the solvent blends that turned out to be good solvents to the donor-acceptor pair. Our results show that the blend film morphology prepared in this way is similar to those obtained from chloroform solutions. [ABSTRACT FROM AUTHOR]

The development of a novel film fabrication strategy, named demulsification‐induced fast solidification (DIFS), for the rapid fabrication of large‐area polymer films is reported in this study. The polymer films are fabricated through dialysis and dipping processes using emulsions and a demulsifier based on the DIFS method. Furthermore, robust and flexible free‐standing films with controllable thicknesses and functionalities, such as tunable mechanical properties (elongation at break of 350–980% and ultimate tensile strength of 0.21–1.88 MPa); excellent optical properties (optical transmittance greater than 52.03% in the visible region, refractive index of 1.4888 ± 0.0001, and Abbe number of 52.1 ± 1.1); and luminescence properties, are rapidly and easily prepared by mechanical exfoliation based on the DIFS method. The results show that this academic concept and fabrication method will provide support for the design and preparation of functional polymer films that are highly desirable for optical, flexible device, and wearable material applications. [ABSTRACT FROM AUTHOR]

Polylactic acid was synthesized from commercial available cheap aqueous lactic acid (85%–90% w/w) using succinic anhydride and SnCl2·2H2O as catalyst in the absence of organic solvents. As a result, polylactic acid with a molecular weight of 60000 was prepared in 10 h. The new procedure is much simple, cheap and outstanding in that the start material is aqueous lactic acid; the catalytic system is environmentally benign. [ABSTRACT FROM AUTHOR]

Data on the solubility of 4,4′-isopropylidenediphenol in organic solvents can be quantitatively correlated with a linear three-parameter equation. The parameters exerting a decisive effect on the solubility are the polarity and basicity of solvents, favoring formation of intermolecular hydrogen bonds. At the same time, an increase in the cohesion energy of the medium decreases the solubility of the title compound. [ABSTRACT FROM AUTHOR]

Abstract: A water-based biphasic reaction process has been developed for conducting exothermic reactions without organic solvents. This procedure is rapid, simple, and suitable for small scale synthesis as well as larger (multi-molar) scale reactions. The preparation of several hundred grams of clofibric acid and analogues by this eco-friendly and energy-efficient procedure is described. Smaller amounts of these compounds were prepared by the friction-activated ‘Grindstone Chemistry’ method described previously. [Copyright &y& Elsevier]

The title compound, [(OC6H4CH=NCH2COO)SbPh3]·CH2Cl2 or [Sb(C6H5)3(C9H7NO3)]·CH2Cl2, is a mononuclear antimony(V) complex. The asymmetric unit comprises two independent mol­ecules of the complex and two solvent molecules. In both complex molecules, the Sb atoms are in distorted octahedral environments. [ABSTRACT FROM AUTHOR]

The article presents the study that examines the synthesis and structure of chemically stable metal-organic polyhedra (MOPs). The study demonstrated that synthesized and characterized two rhombic dodecahedral MOPs. It indicates that the two rhombic dodecahedral MOPs exhibit chemical stability in common organic solvents as well as acidic and basic solutions.

The solubility of 2-aminopyridine in (ethanol + n-butyl acetate) mixed solvents has been measured in the temperature range from (288.15 to 318.15) K by a static analytical method. The concentrations of the 2-aminopyridine in the saturated solution were analyzed by UV spectrometry. A semiempirical equation was proposed to correlate the experimental data. [ABSTRACT FROM AUTHOR]

Abstract: The iodide salt of the pyrylium dye Cy39 (Cy39I, 1) has been suggested as an alternative of its perchlorate salt, which is widely used for biolabeling applications. A new efficient organic solvent-free procedure for synthesis of 1, allowing for a greener approach to the cyanine dyes, is suggested. The unique combination of solubility and thermostability of both the starting materials and the target Cy39 salt made the performance of the synthesis in an aqueous solution as well as reusing of unreacted starting materials possible. [Copyright &y& Elsevier]