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Here, we propose an optimised protocol for controlling the initial water activity (aw) in organic reaction mixtures with soluble lipase to ensure reproducible and consistent enzyme activity measurements. Pre‐equilibration above saturated salt solutions was used to set aw of the reaction media, where aw was tracked with a hygrometer. Consistent stirring of the suspension and volume correction to compensate for solvent evaporation were found to be critical. The protocol was tested on Candida antarctica lipase B (CALB) in soluble and immobilised forms in three organic solvents (acetonitrile, methyl tert‐butyl ether, and hexane) at four different water activities ranging from 0.12 to 0.97. Soluble and immobilised CALB had similar aw‐profiles and showed the highest enzyme activity in hexane. The optimised protocol expands the possibility to study enzyme kinetics from immobilised enzymes to soluble enzymes. [ABSTRACT FROM AUTHOR]

Optimizing synthesis factors of polyamide top layers is an important requirement in the design of thin film composite (TFC) membranes. In this research, the top layer fabrication method (conventional, heat curing, and spin coating), type of acid acceptor (sodium carbonate, sodium hydroxide, and triethylamine), type of organic phase solvent (hexane, heptane, and mixed hexane/heptane), and concentration of surfactant sodium dodecyl sulfate (0, 0.5, and 1 wt %) are selected as the control parameters of this synthesis and optimized using the Taguchi approach. The analysis of variance shows that the layer fabrication method is the most influential parameter on water flux and salt (NaCl) rejection of TFCs. Furthermore, although the type of organic solvent has not a significant contribution to the water flux, it is another significant factor affecting the rejection. The optimized membrane is then used to construct structure–property relationships and to understand the influence of each individual factor on the desalination performance. Accordingly, a TFC membrane with the top layer fabricated by the heat curing method, in the presence of Na2CO3 as the acid acceptor, hexane as the organic phase solvent and 0.5 wt % of the surfactant is prepared that shows water permeance of 2.73 L m−2 h−1 bar−1 and NaCl rejection of 98.1%. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48858. [ABSTRACT FROM AUTHOR]

ABSTRACT Alkyl-substituted polyhedral oligomeric silsesquioxane (POSS) cage is combined with 3,4-ethylenedioxythiophene under the same roof. The corresponding monomer called EDOT-POSS is used to get soluble poly(3,4-ethylenedioxythiophene) (PEDOT-POSS) analogue. Both chemically and electrochemically obtained polymers are soluble in common organic solvents like dichloromethane, chloroform, tetrahydrofuran, and so forth. The PEDOT-POSS has somewhat higher band gap (1.71 eV at 618 nm) than its parent PEDOT (1.60 eV at 627 nm) and as expected the PEDOT-POSS exhibits higher optical contrast (74% at 618 nm) and coloration efficiency (582 cm2/C for 100% switching), lower switching time (0.9 s), higher electrochemical stability (93% of its electroactivity retains after 5000 cycles under ambient conditions) when compared to the PEDOT. A number of advantages of the PEDOT-POSS over the PEDOT can make it a promising material in the areas of electro-optical applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3935-3941 [ABSTRACT FROM AUTHOR]

ABSTRACT Highly ordered porous membranes of cellulose triacetate (CTA) were prepared successfully on ice substrates using breath figure method. The pore size and structure of the membrane were modulated by changing CTA concentrations and substrate materials. As the CTA concentration in the casting solution increased, the pore size in the formed membrane decreased. The regularity of the membrane cast on the ice substrate was much better than that of the membrane cast on glass substrate, because the low temperature of ice substrate slowed down the evaporation rate of organic solvent, which offered enough time for condensed water droplets to self-organize into an ordered array dispersed in the polymer solution before their coagulation. The ordered porous CTA membrane was not only used for microfiltration, but also used for fabrication of functional microstructures. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 552-558 [ABSTRACT FROM AUTHOR]

The exceptional solution processing potential of graphene oxide (GO) is always one of its main advantages over graphene in terms of its industrial relevance in coatings, electronics, and energy storage. However, the presence of a variety of functional groups on the basal plane and edges of GO makes understanding suspension behavior in aqueous and organic solvents, a major challenge. Acoustic spectroscopy can also measure zeta potential to provide unique insight into flocculating, meta-stable, and stable suspensions of GO in deionized water and a variety of organic solvents (including ethanol, ethylene glycol, and mineral oil). As expected, a match between solvent polarity and the polar functional groups on the GO surface favors stable colloidal suspensions accompanied by a smaller aggregate size tending toward disperse individual flakes of GO. This work is significant since it describes the characteristics of GO in solution and its ability to act as a precursor for graphene-based materials. [ABSTRACT FROM AUTHOR]

A novel quinoline-substituted crown ether has been synthesized as a receptor for ion pairs and its binding behavior was investigated in various solvents. The binding of ion pairs in [D6]DMSO and in mixed [D6]DMSO/CD3CN/CDCl3 solvents was studied and the results revealed positive cooperativity effects. As a novel solubilizing agent, the crown ether can extract halide salts into organic media, especially chloride salts. ESI MS provided evidence for the formation of salt-receptor complexes. A recycling experiment showed that the receptor can solubilize salts and can be recovered. This process can be performed as a cycle. This study validates the idea that a straightforward combination of a common anion receptor and a well-studied cation complexation moiety enables the formation of ion-pair receptors and solubilizers of salts in organic solvents. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we prepared poly(3,4-ethylenedioxythiophene) (PEDOT) via the chemical oxidation of the 3,4-ethylenedioxythiophene monomer in a system consisting of miscible binary organic solvents, that is, acetonitrile (CH3CN) and chloroform (CHCl3). This successful technique was then used to synthesize a poly(3,4-ethylenedioxythiophene) (PEDOT)/silver (Ag) nanocomposite as well. In this facile and efficient technique, a higher solubility of the oxidizing reagent, which originated from a relative enhancement in the polarity of the reaction medium, led to significant changes in the optical and thermal behaviors of the resulting products. To investigate the degree of validity of the technique applied, a pure sample of PEDOT (PEDOT I) was also synthesized with CHCl3 alone, and this was then compared with a sample prepared in CH3CN/CHCl3 binary solvents (PEDOT II). To prepare the PEDOT/Ag nanocomposite, first the PEDOT synthesized in binary solvents was thoroughly dissolved in a dimethyl sulfoxide solvent. Next, Ag nanopowder was uniformly dispersed in the previous solution of PEDOT with sonication. The PEDOT/Ag nanocomposite was then precipitated through the addition of a methanol nonsolvent. The approximate size of nano-Ag within the polymer matrix was found to be about 40 nm. Scanning electron microscopy images of the pure PEDOT II and PEDOT/Ag nanocomposite exhibited an agglomerated sponge and nanospherical homogeneity, respectively. In comparison with PEDOT I, considerable redshifts in the ultraviolet-visible absorption spectra of the pure PEDOT II and PEDOT/Ag nanocomposite were observed. In addition, the thermostability order was found to be PEDOT/Ag > PEDOT II > PEDOT I at all temperatures above 300°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2707-2712, 2013 [ABSTRACT FROM AUTHOR]

MoS2 nanosheets with controllable morphologies were successfully synthesized via a novel mixed-solvothermal approach based on interfusing organic solvent in the solution. The morphology of the MoS2 nanosheets was lamellar-like using the mixed water/ethanol/N-Methyl pyrrolidone solvents, whereas that prepared with the mixed water/ethano/ethylene glycol solvents changes to fullerene-like. Because of the structure-directing ability of organic molecules, the mixed solvents were proposed to be responsible for the formation of such different morphologies. The average size of MoS2 nanosheets was approximately 90 nm, and the thickness was about 10-20 nm. The results indicated that the crystalline phase and morphology were largely influenced by calcination and reaction system. [ABSTRACT FROM AUTHOR]

We investigated the effects of two different solvent types and three solution concentrations on the electrospinning of solid state polymerized polyamide 66 (SSP PA66) nanofiber yarns. Nanofiber yarns were electrospun from SSP PA66 solutions in formic acid and formic acid/chloroform (3/1), using two oppositely metallic spinnerets system. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to characterize the morphology and properties of the nanofibrous yarns. Experimental results show that adding chloroform to formic acid as a binary solvent increases viscosity of polymer solution and the nanofibers diameter significantly. XRD patterns reveal that the presence of chloroform affects the crystallinity and the mechanical properties of the produced nanofibrous yarns. PA66 nanofiber yarn from 10 wt % formic acid/chloroform (3/1) solution was successfully electrospun with strength and modulus of 120.16 MPa and 1216.27 MPa respectively. It is also shown that the solution concentration has a significant effect on the modulus of the nanofibers yarns. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Acid-catalyzed condensation of 1,3-butadiene with para-quinones and oxidation of resulting adducts can be performed as a one-pot process in the presence of aqueous solutions of Mo-V-phosphoric heteropoly acids (HPA) with the general formula H aP zMo yV xO b. These solutions have bifunctional catalytic properties; they are both strong Brønsted acids and reversible oxidants. Condensation of hydroquinone, 1,4-benzoquinone, or 1,4-naphthoquinone with 1,3-butadiene in the HPA solutions results in 9,10-anthraquinone (AQ) in a mixture with tetrahydro-AQ (THA) and dihydro-AQ (DHA). In this one-pot process, which proceeds in the absence of organic solvents, the HPA solution is reduced. A slightly soluble mixture of THA, DHA, and AQ is precipitated and filtered off. The non-Keggin-type H12P3Mo18V7O85 solution is the most effective in this process. This solution can be rapidly regenerated by dioxygen or air at temperatures of up to 170 °C and then reused. The prepared THA+DHA+AQ mixture can be used as a catalyst for alkaline delignification of wood. Our homogeneous bifunctional HPA catalyst is very stable and promising for use in similar one-pot processes. [ABSTRACT FROM AUTHOR]

Novel bis(azo) dyes were successfully prepared from the coupling of either natural cardanol or its hydrogenated derivative with a series of diazotized aromatic amines and diamines. These new dyes were fully characterized by NMR, infrared and UV-visible spectroscopy and mass spectrometry. The dyes are highly soluble in a variety of common organic solvents and gasoline as a consequence of the cardanol unit. The physical properties of gasoline according to American Society for Testing and Materials standard were unaffected by the presence of the bis(azo) dye derived from 1-(4aminophenylazo)-2-naphthol at a concentration of 6 ppm and the dye showed excellent stability over a 3 month period. [ABSTRACT FROM AUTHOR]

In this work, we have evaluated how well the general assisted model building with energy refinement (AMBER) force field performs in studying the dynamic properties of liquids. Diffusion coefficients ( D) have been predicted for 17 solvents, five organic compounds in aqueous solutions, four proteins in aqueous solutions, and nine organic compounds in nonaqueous solutions. An efficient sampling strategy has been proposed and tested in the calculation of the diffusion coefficients of solutes in solutions. There are two major findings of this study. First of all, the diffusion coefficients of organic solutes in aqueous solution can be well predicted: the average unsigned errors and the root mean square errors are 0.137 and 0.171 × 10−5 cm−2 s−1, respectively. Second, although the absolute values of D cannot be predicted, good correlations have been achieved for eight organic solvents with experimental data ( R2 = 0.784), four proteins in aqueous solutions ( R2 = 0.996), and nine organic compounds in nonaqueous solutions ( R2 = 0.834). The temperature dependent behaviors of three solvents, namely, TIP3P water, dimethyl sulfoxide, and cyclohexane have been studied. The major molecular dynamics (MD) settings, such as the sizes of simulation boxes and with/without wrapping the coordinates of MD snapshots into the primary simulation boxes have been explored. We have concluded that our sampling strategy that averaging the mean square displacement collected in multiple short-MD simulations is efficient in predicting diffusion coefficients of solutes at infinite dilution. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 [ABSTRACT FROM AUTHOR]

The self-assembly of structurally discrete entities, and supramolecular chemistry in general, continues to expand into the aqueous realm. To do so, however, requires a firm understanding of the properties of aqueous solution, and how these 'change the rules' for binding and assembly relative to organic solvents. In this mini-review we highlight the state-of-the-art understanding of the supramolecular properties of water, and how these influence the design of hosts and self-assembling systems. [ABSTRACT FROM AUTHOR]

The habit of the organic nonlinear optical material metanitroaniline mNA crystallized from different organic solvents such as acetone, benzene, ethyl acetate, nhexane, methanol and toluene were studied. Solubility of mNA in these solvents at various temperatures in the range between 288 and 323 K was determined by gravimetric method. Crystals were grown by restricted evaporation of solvents method. Solutions with different solvents having different chemical nature and polarity yielded crystals with different habits: onedimensional needles, twodimensional rhombic platelets and threedimensional octahedral. In addition, the mNA crystals show unidirectional growth behaviour along its polar [001] direction irrespective of the solvents used. All the grown crystals were found to be orthorhombic system with point group mm2 and space group Pbc21which was confirmed by powder Xray diffraction study. Optical transmittance study showed that the grown mNA single crystals have optical transparency in the wavelength range between 430 and 1550 nm. SHG efficiency of the grown mNA crystal was 3 times grater than KDP. © 2010 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]

The existence of single-wall carbon nanotubes (SWNTs) in organic solvents, in the form of clusters, is discussed. A theory is developed based on a bundlet model for clusters, describing the distribution function of clusters by size. The phenomena have a unified explanation in the bundlet model of clusters, in accordance with which the free energy of an SWNT, involved in a cluster, is combined from two components: a volume one, proportional to the number of molecules n in a cluster, and a surface one proportional to n1/2. The bundlet model for clusters enables describing the distribution function of SWNT clusters by size. The droplet model is formally analogous to the one for fullerene clusters. From purely geometrical differences, the models predict different behaviors. Single-wall carbon nanocones (SWNCs) of various disclinations are investigated via energetic and structural analyses. Several SWNC's terminations are studied, which are different among each other because of the type of closing structure and the arrangement of them. The SWNC packing efficiencies, and interaction-energy parameters, are intermediate between the ones of fullerene and SWNT clusters; an in-between behavior is expected. However, SWNC properties are calculated closer to those of fullerene and more distant from those of SWNT. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [ABSTRACT FROM AUTHOR]

LST-03 lipase from an organic solvent-tolerant Pseudomonas aeruginosa LST-03 has high stability and activity in the presence of various organic solvents. In this research, enhancement of organic solvent-stability of LST-03 lipase was attempted by directed evolution. The structural gene of the LST-03 lipase was amplified by the error prone-PCR method. Organic solvent-stability of the mutated lipases was assayed by formation of a clear zone of agar which contained dimethyl sulfoxide (DMSO) and tri-n-butyrin and which overlaid a plate medium. And the organic solvent-stability was also confirmed by measuring the half-life of activity in the presence of DMSO. Four mutated enzymes were selected on the basis of their high organic solvent-stability in the presence of DMSO. The organic solvent-stabilities of mutated LST-03 lipase in the presence of various organic solvents were measured and their mutated amino acid residues were identified. The half-lives of the LST-03-R65 lipase in the presence of cyclohexane and n-decane were about 9 to 11-fold longer than those of the wild-type lipase, respectively. Some substituted amino acid residues of mutated LST-03 lipases have been located at the surface of the enzyme molecules, while some other amino acid residues have been changed from neutral to basic residues. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [ABSTRACT FROM AUTHOR]

The article provides information about a dose-finding study focusing on the critical effect of standard white spirits (stdWS) on human health. According to the study, exposure to stdWS may cause acute irritation of the mucous membranes and acute or chronic effects on the central nervous system. It also notes that stdWS has higher irritation ratings compared with dearomatized white spirits (deWS). Moreover, a study on eight volunteers who were recruited among medical students at the Karolinska Institutet in Solna, Sweden is also presented.

The article focuses on a study aiming to compare dearomatized white spirits (deWS) and standard white spirits (stdWS) with respect to mucosal and sensory irritation and inflammation. According to the study, stdWS has stronger ratings of chemosensory effects than for deWS. Despite of the hazardous effect of these white spirits, still, there is no evidence that one of the two types of white spirits induced sensory irritation. Moreover, a study on twelve volunteers who were exposed to 100 or 300 mg m-3 deWS or stdWS, or to clean air is also presented.

A novel triarmed cis-1, 3, 5-cyclohexanetricarboxamides gelator, functionalized by three azobenzene moieties grafted with three long alkyl chains, was designed and synthesized. The gelator can gel most of the organic solvents in low concentration. The morphologies of the xerogels show one-dimensional aggregated bundles or helical fibres. The azobenzene groups in the gel state form H-type aggregation and perform expected trans–cis photoisomerization with a gel to sol phase transition upon irradiation of UV light. The main driving force for gelation is intermolecular hydrogen bonding between amides and π–π interaction of azobenzene moieties. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Formations of triplet state, molecular cation radical, and phenoxyl radical of 3,4-methylenedioxy phenol (sesamol, SOH) in organic solvents have been investigated by laser photolysis as well as pulse radiolysis techniques. Photolysis of SOH in cyclohexane has been found to produce both triplet state (λmax ∼ 480 nm) and phenoxyl radical (425–430 nm) of SOH by mono-photonic processes. However, radical cation (λmax = 450 nm) and phenoxyl radical of SOH have been observed on radiolysis in cyclohexane. Further, radiolysis of SOH in benzene has been found to produce phenoxyl radical only. Mechanism of phenoxyl radical formation by photo-excitation of SOH has been studied and triplet energy level of SOH is estimated to lie between 1.85 and 2.64 eV. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Organic solvents are known to bring about dehydration of proteins, the molecular basis of which has remained uncharacterized. The dehydration effect in many cases leads to eventual unfolding of proteins through the macroscopic solvent effect. In some cases, the organic solvent molecules also bind to protein surfaces, thereby forcing local unfolding. The X-ray structure of hen egg-white lysozyme co-crystallized in the presence of alcohols with varying hydrophobicities has been studied. It was noticed that although the alcohols have very little effect on the conformation of the overall protein structure, they profoundly affect protein hydration and disorder of the bound waters. Systematic analysis of the water structure around the lysozyme molecule suggests that an increasing order of hydrophobicity of alcohols is directly proportional to the higher number of weakly bound waters in the protein. As anticipated, the water molecules in the native structure with high temperature factors (≥40 Ų) attain higher disorder in the presence of alcohols. It is believed that the disorder induced in the water molecules is a direct consequence of alcohol binding. [ABSTRACT FROM AUTHOR]

Salt hydrate pairs were used to control water activity in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate. It was shown that salt hydrate pairs behave essentially the same in ionic liquids as they do in organic solvents as long as they do not dissolve. Initial rate-water activity profiles were prepared for the immobilized Candida antarctica lipase catalyzed synthesis of 2-ethylhexyl methacrylate. The ability to use salt hydrate pairs for the control of water activity in ionic liquids should allow for improved comparison of enzyme activity and specificity in ionic liquids and conventional solvents. [ABSTRACT FROM AUTHOR]

Environmental stress cracking has been identified as a crack propagating mechanism in polyurethane-insulated, heart pacemaker leads, which is directly related to specific lead design parameters. Lead designs imposing excessive stress on the polyurethane insulation through an interference fit between the coil and polymer have demonstrated insulation failures. Conversely, low-stress designs have shown virtually no insulation problems. The higher-stress designs have used organic solvents to facilitate coil placement during manufacturing, which may result in lowering the polymers ability to resist the higher stress. In addition, a specific silver-containing coil wire composition has been found to galvanically corrode upon body fluid intrusion into the lead, ionizing the silver. These ions interact with the polyurethane polymer resulting in the loss of polymer strength. All polyurethane lead failures to date have been specific to high stress and/or chemical interaction. Leads using low-stress designs and nonreactive coil wire compositions continue to demonstrates a positive clinical experience. [ABSTRACT FROM AUTHOR]

In this report, an automated 11C- N-methyl- α-amino-isobutyric acid production on a Tracerlab FXC Pro module is described. Bioburden to the sterile filter was minimized during solid-phase extraction formulation of the HPLC purified product by the use of sterile aqueous solutions. The optimized solid-phase extraction formulation conditions are fast, give a high recovery of the product, and effectively remove organic solvents and adjust the pH. The final product was obtained within 30-35 min, delivering 1.5-5 GBq in 10 mL sterile phosphate buffer. The product fulfills in every respect our stringent batch release specifications including residual solvents, bioburden, and sterility. The robustness of the automated 11C- N-methyl- α-amino-isobutyric acid production has been demonstrated during more than 40 productions for preclinical use without any failures in regard to product amounts or release specifications. Copyright © 2013 John Wiley & Sons, Ltd. [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]

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]

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]

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Review: 72 refs. [ABSTRACT FROM AUTHOR]