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Objective: Analytical gas chromatography in line with a flame ionisation detector (GC-FID) method was developed and validated for evaluating organic solvents in radiopharmaceutical samples [18F]fluoro-ethyl-tyrosine ([18F]FET), [18F]fluoromisonidazole ([18F]FMISO) and [18F]fluorothymidine ([18F]FLT). Variables of the carrier gas flow (mL min−1) and a split ratio of injection on the response of analysis time and resolution were optimised with the assistance of a two-level full factorial design and desirability function of Derringer. Methods: The proposed procedure was validated following the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q2 (R1) guideline. Results: Excellent linearity, R2 > 0.990 indicated that approximately 99% of the variance in the response could be predicted from ethanol and acetonitrile concentrations ranging from 0.8 to 7.5 mg mL−1 and 0.1 to 1.0 mg mL−1, respectively. The proposed procedure proved to be selective, sensitive and accurate (85 to 105%), with excellent repeatability and precision (relative standard deviation (RSD) 0.05). Conclusion: The proposed method has also been successfully used for the quantitative determination of ethanol and acetonitrile in [18F]FET, [18F]FMISO and [18F]FLT samples. Analytes were well resolved (R, 7.9 – 8.1) within 3.5 min even though the column had a larger, 0.53 mm internal diameter. The proposed method is, therefore, relevant for routine organic solvent quality control analysis of any 18F-radiopharmaceutical derivatives.

The purpose of this study was to assess the efficacy of desocclusol, eucalyptol and d-limonene on removal of gutta-percha, their effect on microhardness of dentin, and the antibacterial properties against Enterococcus faecalis (E. faecalis) during root canal retreatment. Forty single-canal roots, obturated with gutta-percha, were prepared and randomly divided into 4 groups (n=10). Group that free of any solvent was control group. Three of experimental groups were exposed to desocclusol, eucalyptol and d-limonene respectively during endodontic retreatment. Efficacy of each solvent was assessed by comparation of time duration, amount of apical extrusion and residual debris in the root canals. Vickers microhardness of each sample was recorded. Antibacterial activity on E. faecalis was also observed. The data were subjected to repeated statistical analysis. All three organic solvents were found to be effective in the removal of root canal filling material compared with control group (p<0.05). D-limonene was more effective in significantly increasing the microhardness of dentin compared with desocclusol, which decreased the microhardness of root canal dentin (p<0.05). In the meantime, d-limonene had a stronger antibacterial activity than eucalyptol, while desocclusol had no obvious bacterial inhibition. These three organic solvents are all effective in removing gutta-percha in endodontic retreatment. D-limonene can increase the microhardness of dentin and has a stronger inhibitory effect on E. faecalis than desocclusol and eucalyptol. [ABSTRACT FROM AUTHOR]

A novel and simplified gradient IC-HRMS approach is presented in this work for forensic profiling of ionic energetic material residues, including low-order explosives and gunshot residue (GSR). This new method incorporated ethanolic eluents to facilitate direct coupling of IC and HRMS without auxiliary post-column infusion pumps that are traditionally used to assist with gas phase transfer. Ethanolic eluents also enabled better integration with an in-service protocol for direct analysis of high-order organic explosives by IC-HRMS, without requiring solvent exchange before injection. Excellent method performance was achieved, enabling both full scan qualitative and quantitative analysis, as required. In particular, linearity for 19 targeted compounds yielded R2 > 0.99 across several orders of magnitude, with trace analysis possible at the low-mid pg level. Reproducibility and mass accuracies were also excellent, with peak area %RSDs <10%, t R %RSDs <0.4% and δ m/z < 3 ppm. The method was applied to targeted analysis of latent fingermarks and swabbed hand sweat samples to determine contact with a black-powder substitute containing nitrate, benzoate and perchlorate. When combined with principal component analysis (PCA), the effect of time since handling on recorded signals could be interpreted further in order to support forensic investigations. In a second, non-targeted application, PCA using full scan IC-HRMS data enabled classification of GSR from three different types of ammunition. An additional 20 markers of GSR were tentatively identified in silico , in addition to the 15 anions detected during targeted analysis. This new approach therefore streamlines and adds consistency and flexibility to forensic analysis of ionic energetic material. Furthermore, it also has implications for targeted, non-targeted and suspect screening applications in other fields by expanding the separation space to low molecular weight inorganic and organic anions. Image 1 • A novel gradient IC-HRMS approach developed and validated for explosive analysis. • An ethanolic eluent allowed direct analysis of extracts in organic solvent. • Both quantitative targeted and non-targeted analysis demonstrated. • Retrospective HRMS data mining approach applied for advanced forensic applications. [ABSTRACT FROM AUTHOR]

A fast and simplified analytical procedure was developed and validated for the direct determination of organic solvents (acetonitrile and ethanol) in radiopharmaceuticals samples ([18F]FMISO, [18F]FES and [18F]FLT) by gas chromatography coupled with flame ionization detection (GC-FID). Optimization studies were performed with the aid of two-level full factorial design. The optimum conditions were located using Derringer's desirability function. Procedure validation assured the compliance of the assay to Brazilian regulatory agencies standards (ANVISA and INMETRO). Values for LOD and LOQ were commensurate with the level at which the impurities must be controlled. Good linearity was achieved (R ≥ 0.990) for acetonitrile and ethanol concentrations ranging from 0.003 to 0.09% (w/v) and 2.1 to 11.0% (v/v), respectively. Accuracy and precision assessments were performed using samples fortified with standards (spiked samples). The developed procedure proved to be selective, sensitive, accurate (95.9–117.8% of nominal values) and precise (RSD ≤ 9.7%). The validated procedure was successfully used to assess organic solvents levels in a Brazilian radiopharmaceuticals samples manufactured by Radiopharmaceutical Research and Production Unit of Nuclear Technology Development Center (CDTN), in Belo Horizonte (Brazil). The analytes could be well resolved in 1.5 min and accurately determined in three different types of radiopharmaceuticals. This procedure is applicable to samples even with high ethanol content up to 11% (v/v). Other advantages include no sample preparation, short chromatographic separation time and minimum manual operation. As results, the proposed procedure can be useful in the routine analysis for the determination of acetonitrile and ethanol in radiopharmaceutical samples. • Fast and reliable analysis of organic solvents in radiopharmaceuticals samples. • Experimental variables were optimized by the multivariate approach. • The developed method showed to be applicable to formulations even with high ethanol concentration up to 11.0% (v/v). • Procedure is feasible for the radiopharmaceutical specific monograph actualization. [ABSTRACT FROM AUTHOR]

• PEEK capillary was used in CE-MS for tolerance to organic solvents. • PEEK capillary showed excellent stability in commonly used organic solvents. • PEEK capillary showed good separation performance in NACE and organic-aqueous CE. • This method was successfully used to quantitative analysis of peimine and peiminine. Nonaqueous capillary electrophoresis (CE) and organic-aqueous CE using high content of organic solvents are common techniques in capillary electrophoresis-mass spectrometry (CE-MS) due to various advantages. However, the long-term stability of commonly used polyimide coated fused silica capillary remains a major problem that polyimide coating is prone to swelling in organic solvents and aminolysis in alkaline buffer, which cause serious problems like irregular electrospray, current drop or clogging event. In this work, robust PEEK capillary was used as separation capillary for tolerance to high content of organic solvents in CE-MS system. It is interesting that the high mechanical and chemical stability of PEEK capillary ensured stable CE separation and electrospray when used in CE-MS. All quantitative experiments were accomplished by single PEEK capillary. In addition, the using of organic solvents as running buffer reduced adsorption of hydrophobic compounds on PEEK capillary wall and improved the symmetry of peak shape. The PEEK-based CE-MS method showed good separation performance in analysis of several groups of active alkaloids in traditional Chinese medicines and was applied for quantitative analysis of peimine and peiminine in Bulbus Fritillariae thunbergii herb with high sensitivity. Based on the advantages like simple pretreatment, easy to cut, stable and good separation performance of PEEK column in CE-MS, this study provides an effective way for improving the stability and employment of high content of organic solvents in CE-MS analysis. [ABSTRACT FROM AUTHOR]

Graphical abstract Lactose fatty acid ester was synthesized using commercially available aluminosilicate zeolite as Lewis acid catalyst in different organic solvents. Reactions were done at 55 °C using pure or raw lactose with lauric acid to synthesize lactose monolaurate as biosurfactant without using lipase. Highlights • A commercial zeolite was used as a catalyst for esterification of lactose with lauric acid. • Pure and raw lactose derived from whey were used in esterification. • Products were easily purified using a solvent extraction method. • Products showed low surface and interfacial tensions compared to industrial surfactants. Abstract Sugar-based biosurfactants are safer and healthier alternatives to synthetic surfactants especially for use in the food industry. In this work, biosurfactants were synthesized via the esterification of lactose with lauric acid in different organic solvents without using lipase or other enzymes. Commercial aluminosilicate zeolite was used as a catalyst. Conversions of up to 92% were obtained for pure lactose and 38% for raw lactose from whey. Surface-active properties including surface tension, interfacial tension, and contact angle were measured. All samples showed surface tensions lower than sodium dodecyl sulfate, SDS (19.59–36.57 mN/m compared to 38.8 mN/m for SDS) and interfacial tensions comparable with it (9.47–12.18 mN/m compared to 4.77 mN/m for SDS). Results showed that aluminosilicate zeolites can be used for the synthesis of lactose esters, which have potential applications as biosurfactants for the food industry featuring low surface and interfacial tensions. [ABSTRACT FROM AUTHOR]

Graphene is the most widely investigated carbon nanomaterial having two-dimensional honeycomb lattice structure. Recently, it has attracted worldwide attention due to its remarkable electrical, thermal, mechanical, chemical and optical properties, which are highly suitable for various electronic device applications. Various methods of graphene synthesis have been utilized for the production of graphene each having its own advantages and disadvantages. Liquid phase exfoliation method uses top-down approach and has the advantages of being environment friendly, facile and economically viable. Liquid phase exfoliated graphene is highly suitable for making thin films for their potential applications in electronic devices such as thin films transistors, transparent electrodes, light-emitting diodes, supercapacitors, etc. In this paper, a comparative study of different exfoliation medium used for liquid phase exfoliation of graphene such as organic solvents, ionic liquids, surfactants, polymers and acids are described. Because of the usually low concentration of graphene (< 0.01 mg/mL) obtained from liquid phase exfoliation method, research has been done for enhancing the concentration. Recent progress made in enhancing graphene concentration in organic solvents by adding various additives is reported here. Finally, we discuss the challenges and future prospects of improving liquid phase exfoliation of graphene for modern electronics devices. [ABSTRACT FROM AUTHOR]

Highlights • 5-Hydroxymethylfurfural (HMF) and levulinic acid (LA) are important biomass-derived platform chemicals. • Different lignocellulosic biomass pretreatment technologies were reviewed. • Mechanistic analysis of HMF and LA production provided theoretical basis for further study. • The comparison of different reaction systems for production of HMF and LA supported research orientation for future. Abstract 5-Hydroxymethylfurfural (HMF) and levulinic acid (LA), produced from lignocellulosic biomass, can be catalytically upgraded to valuable chemicals and fuels. Lignocellulosic biomass has been considered as an alternative carbon resource for fossil. This work reviews the recent development of HMF and LA production from lignocellulosic biomass, which focuses on pretreatment of lignocellulosic biomass, preparation principle for HMF and LA and the upgrading application. Traditionally, the preparation of HMF and LA is catalyzed by mineral acids in aqueous solutions. Recently, using organic solvents as reaction medium have been investigated in many reports. We carefully summary the production process of HMF and LA with homogeneous or heterogeneous catalysts in organic solvents; meanwhile, the advantages and challenges in different reaction systems are also pointed out. Furthermore, the applications of HMF and LA are described in details. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Poly-diallyldimethylammonium chloride bound proteins were effectively mobilized into hydrophobic hexane phase. • Around 82% albumin separation was achieved. • Key factors were neutral system pH (7) and low polymer concentration (0.5 w/w %). • Easy recovery of hexane possible due to its water immiscible nature. Abstract Separation of proteins from a complex multi-component suspension of broken down cells is technically challenging. In this regard, a technique that is capable of distinguishing proteins from other major cellular components (such as carbohydrates, lipids, and other cellular debris) could immensely simplify downstream processing. In this work, we report the ability to use the inherent zwitterionic properties of proteins to latch amphiphilic cationic electrolytes on to protein surfaces so that proteins can be extracted from an aqueous suspension into a water-immiscible organic solvent. Here we show the separation of egg albumin (a model protein) from an aqueous suspension to adjacent hexane phase using poly-(diallyl dimethyl ammonium) chloride (PolyDADMAC). Results show that, under optimum pH and polyelectrolyte concentrations, proteins can be successfully migrated from water to the adjacent hexane phase. The amount and molecular weight of electrolyte, and solution pH played vital roles in determining the amount of protein that could be migrated. Low molecular weight polyelectrolyte under neutral pH conditions, low equilibration time and 1:2 hexane: water ratio favored highest protein separation (∼85% dry weight). FTIR studies indicated that the secondary structure of the protein was preserved after migration of the protein from the aqueous phase to solvent under the protection of the polyelectrolyte coating. The results suggest that ionic electrolytes with hydrophobic moieties could be used as molecular transport vehicles to safely separate proteins from a bulk aqueous phase to an immiscible solvent phase. [ABSTRACT FROM AUTHOR]

Abstract In this work, a novel thin-film composite membrane composed of a polyester film on a cellulose support was successfully synthesised. The polyester film was formed from the interfacial reaction between catechin, a bio-derived poly-phenol, and terephthaloyl chloride (TPC). The cellulose support was prepared by non-solvent induced phase separation from a 12.5 wt% cellulose dope solution in 1-ethyl-3-methylimidazolium acetate ionic liquid. The composite membrane was characterised by Fourier Transform Infrared and X-Ray Photoelectron Spectroscopy to confirm the success of the interfacial reaction. Scanning electron and atomic force microscopy were used to study the surface morphology and roughness of the membranes produced. The performance of the composite membranes in terms of solvent permeance and solute rejection was investigated by studying the rejection of a broad range of different molecular weight dyes in dimethylformamide (DMF) solution. The membranes showed an average DMF permeance of 1.2 L m−2 h−1 bar−1 with a molecular weight cut-off of around 500 g mol−1. The membrane was stable in DMF over 30 days with no significant change in performance. The membrane has potential application in the food and pharmaceutical industries. Highlights • A catechin/cellulose composite nanofiltration membrane has been developed. • The membrane made from bio-derived materials is stable in dimethylformamide. • The cross-linked catechin selective layer exhibits high DMF fluxes. • The membrane rejects molecules with a molecular weight higher 500 g mol−1. [ABSTRACT FROM AUTHOR]

Abstract: Organic micro‐ and nanostructures are expected to be promising candidates for micro‐ and nanophotonic materials with desirable properties owing to their low cost, flexible molecular design, and tunable self‐assembly. Among these candidates, well‐known squaraine dyes (SQs) have rarely been investigated because of their nonfluorescent properties in the solid state and because their optical behavior varies with changes in morphology. In this contribution, two novel 1,2‐SQs, SQM and SQB, with strong bright‐yellow to red fluorescence emission in the crystalline state, were designed and structured at the molecular level and by solvent adjustment. Their self‐assembly behavior was studied, and it was revealed that the SQM assembly provided 1D microrods, whereas 1D microrods (Z‐SQB⋅CH2Cl2) and 2D microplates (E‐SQB⋅2 CH3OH) could be obtained from SQB assemblies through a solution‐based self‐assembly method. The varied assembly behaviors of these SQs were attributed to different π–π stacking interactions that resulted in different molecular conformations and packing modes. These assemblies exhibited distinct optical properties, and in particular, SQB⋅solvent assemblies showed multiple thermo‐ and vapochromic effects. Thus, the SQB assemblies are potential fluorescent sensors for organic solvent vapors. More importantly, favorable optical‐waveguide properties were observed in these SQ‐based microstructures. [ABSTRACT FROM AUTHOR]

Absorption, stability and reactivity of ozone in water are critical parameters to determine its efficiency in microbial inactivation. In this study, the influence of four water-soluble organic solvents commonly discharged from industrial lines into wastewater systems, namely; ethanol, methanol, ethyl acetate and dimethyl sulfoxide (DMSO) on the ozone-facilitated inactivation of Escherichia coli and Staphylococcus aureus in water was investigated. Ozone absorption (up to 12 min) as a function of ozone aeration time, and the decomposition rate were spectrophotometrically monitored in the presence of 2.5% and 5% concentrations of each organic solvent. Their consequent effect on bacterial inactivation was determined. The inactivation kinetics were described using the efficiency factor Hom model. Residual concentrations of absorbed ozone in solutions with ethyl acetate or DMSO were relatively higher than those in methanol or ethanol-containing solutions. DMSO and ethyl acetate enhanced the stability of ozone in water, characterised by a lower decomposition rate constant in DMSO ( k d  = 3.81 × 10 −2  M −1  s −1 ) and ethyl acetate ( k d  = 4.45 × 10 −2  M −1  s −1 ) solutions, in contrast with that in methanol ( k d  = 1.13 × 10 −1  M −1  s −1 ), where the decomposition rate was higher. The faster absorption and stability of ozone in ethyl acetate and DMSO corresponded with an observed increase in the log inactivation of E. coli and S. aureus by approximately 2-fold relative to that in methanol. [ABSTRACT FROM AUTHOR]

Monocarboxylate functionalized pillar[5]arene 1 with excellent solubility in organic solvent was prepared. It could be abosorpted on the surface of gold nanorod spontaneously. Then, hybrid supramolecular materials were constructed from 1 stabilized gold nanorods and a linear dinitriles 2 driven by host–guest interaction. Interestingly, the hybrid supramolecular materials show dynamic near-infrared (NIR) and redox dual-responsive reversible properties. 1 H nuclear magnetic resonance (NMR) spectra, transmission electron microscopy (TEM), scanning electron microscopy (SEM), optical microscopy, and specific viscosity were used to characterize the obtained materials and the reversible behavior under external stimuli. We suggest that this NIR and redox dual-responsiveness properties would be useful in preparation other smart materials and have potential in vivo applications. [ABSTRACT FROM AUTHOR]

Solubility of trioctylmethylammonium chloride (TOMAC) in supercritical carbon dioxide (SCCO 2 ) was measured at 313, 323 and 333 K with pressure ranging from 10 to 30 MPa. Solubilities (in mole fraction) ranged from 0.5 × 10 −5 to 12.7 × 10 −5 in the investigated region. Influence of co-solvents on the solubility of TOMAC was studied at 313 and 323 K. Among the four models employed for correlating solubility of TOMAC in neat SCCO 2 , association theory based on van Laar activity coefficient model resulted in average deviation of 2%, while use of other models resulted within 10%. Solubility data were found to be self-consistent based on the Mendez-Teja model. Two new models were developed for the ternary system (SCCO 2  + co-solvent + liquid solute) based upon association theory along with the Wilson and van Laar activity coefficient models. These models successfully correlated solubility of TOMAC in SCCO 2  + co-solvent with an average deviation of <8%. [ABSTRACT FROM AUTHOR]

ABSTRACT: A premixing method to produce polymer nanocomposites with cellulose nanocrystals (CNCs) is reported. This method involves the dissolution and dispersion of a polymer and CNCs in an organic solvent, co‐precipitation into water, drying of the resulting particles, and subsequent melt processing. The key aspect of the method is that it allows the kinetic trapping of well‐dispersed CNCs in the polymer. Although the nanocomposite must be dried before subsequent melt‐processing, the organic solvent can be removed by extraction in water and recycled, leaving only residual water in the composite, which is easily eliminated. This process presents numerous advantages compared with the time‐consuming solvent casting process, which often suffers from incomplete organic solvent evaporation. As a testbed, polyurethane (PU) composites with up to 30% of CNCs were prepared. These materials were either melt‐processed as produced or used as a masterbatch, i.e., they were diluted via melt‐mixing with neat polymer toward nanocomposites with lower filler content. All nanocomposites prepared using this approach had a homogeneous appearance. They displayed similar mechanical properties as the corresponding reference materials made by solvent casting, and significantly better properties than materials prepared by direct melt mixing. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45648. [ABSTRACT FROM AUTHOR]

The absorption energies of the Q y bands of chlorophylls a and b (Chl a and Chl b ) in organic solvents (acetone, diethyl ether, and ethanol) were calculated by combining molecular dynamics simulations and quantum mechanical/molecular mechanical approaches with an explicit solvent model. It was found that excitation-energy calculations by time-dependent density functional theory (DFT) using the CAM-B3LYP functional, following DFT geometry optimizations with the B3LYP functional, accurately reproduced the differences between the observed absorption energies of Chl a /Chl b in each solvent. The calculated energies were within a root-mean-square deviation of 0.0014 eV from the observed values when the CAM-B3LYP-related parameter μ , which is associated with the long-range correlation, was set to 0.14. Calculations using μ = 0.14 also reproduced the observed transition-dipole strengths of the Q y -band moments, and the observed absorption spectra, with linewidths of ∼0.05 eV. These results suggest that μ = 0.14 can be used for absorption-energy calculations for Chl a and Chl b . [ABSTRACT FROM AUTHOR]

We fabricated inverted perovskite solar cells (PSCs) using different organic solvents, including chloroform, chlorobenzene, and 1,2-dichlorobenzene, to prepare the phenyl-C61-butyric acid methyl ester (PCBM) layer. We found that using 1,2-dichlorobenzene resulted in smoother PCBM morphology compared to the chloroform- and chlorobenzene-based solvents; this would be beneficial for improving charge transport between the perovskite and cathode. In accordance with the morphologies, the average power conversion efficiency (PCE) of 1,2-dichlorobenzene-processed PSCs was 17.5%, which was higher than those of chlorobenzene- and chloroform-processed PSCs (16.7% and 11.0%, respectively) The best-performing cell was fabricated using 1,2-dichlorobenzene, showing PCEs of 17.9% and 18.2% in forward and reverse scans, respectively. We found that the conductivity and the PCBM surface roughness showed good linear dependence on the evaporation rate of the solvent, which could be an important factor for identifying new good organic solvents. [ABSTRACT FROM AUTHOR]

Abstract: An 17O NMR spectroscopy survey of more than 100 ubiquitous organic solvents and compounds, including some typical oxofluorinated solvents such as hexafluoroisopropanol, trifluoroethanol, trifluoroacetic acid, and others, is presented with D2O as a reference. A strong alternating α,β−CF3‐substituent chemical shift effect was thus observed. This alternating deshielding–shielding effect is suspected to have a role in the exceptional properties of these oxofluorinated solvents, notably in oxidative cross‐coupling reactions. [ABSTRACT FROM AUTHOR]

Abstract: A semicrystalline polymer actuator, which is responsive to solvent vapor with fast and large scale locomotion, is described. The thermoset semicrystalline polymer can be easily synthesized from crystallizable polyester segment poly (ε‐caprolactone) and isophorone diisocyanate trimer. Organic solvent vapor is used to induce the reversible swelling‐crystallization conversion of the crystallizable polyester segment, resulting in its expansion/shrinkage. The contraction of the polymer actuator (1 mm thick) needs only ≈4 s in room temperature. When exposed to air the polymer actuator can exhibit a fast self‐oscillation. Then, a soft crawler based on this polymer is demonstrated. Driven by organic solvent it walks rapidly and steadily. The microscope images show the fast swelling‐crystallization conversion that gives rise to reversible shape changes of the polymer. [ABSTRACT FROM AUTHOR]

The interactions of isonicotinamide (INA) with seven common solvents (acetic acid, acetonitrile, acetone, chloroform, ethyl acetate, and methanol) have been studied to examine solute-solvent effects on the nucleation of INA from these solvents. In a simple model of 1:1 solute-solvent interactions, the strongest INA-solvent interaction is with acetic acid (binding energy, ΔEbind = -64.05 kJ mol-1) and the weakest is with chloroform (ΔEbind = -24.85 kJ mol-1). This arises since acetic acid and INA form a hydrogen-bonding motif containing two moderate strength N-H···O hydrogen bonds, while chloroform and INA have a single weak C-H···O hydrogen bond. Taking acetic acid, chloroform, and methanol, the solvents with the strongest, the weakest, and an intermediate strength INA-solvent binding energy, the solvation of INA was studied to compare it with the 1:1 model. Acetic acid has the strongest binding energy (-872.24 kJ mol-1) and solvation energy (-341.20 kJ mol-1) with chloroform binding energy (-517.72 kJ mol-1) and solvation energy (-199.05 kJ mol-1). Methanol has intermediate binding energy (-814.19 kJ mol-1) and solvation energies (-320.81 kJ mol-1). These results further confirm the recent the findings which indicate that the key trends in solvent-solute interactions can be determined from a simple and efficient 1:1 dimer model and can be used to predict ease of nucleation with stronger binding energies correlating to slower, more difficult nucleation. A limit of this model is revealed by considering alcohol and acid solvents with longer alkyl chains. [ABSTRACT FROM AUTHOR]

High-flux mixed matrix membranes (MMMs) for organic solvent nanofiltration (OSN) were designed using amine-functionalized multi-walled carbon nanotubes (NH 2 -MWCNTs) and P84 polyimide with the aid of 1,6-hexanediamine (HDA) as a cross-linker and thermal annealing to tighten the pore size. The embedding of hydrophilic NH 2 -MWCNTs into the P84 matrix not only enhanced membrane's porosity, sorption capacity, and liquid transport but also resulted in an amidation reaction between them. The resultant MMMs had higher water, ethanol, and isopropanol permeances than the pristine P84 one. However, a higher loading of NH 2 -MWCNTs diminished the rejection due to visible agglomeration among them. The cross-linked MMMs consisting of 2 mg/g of NH 2 -MWCNTs/P84 showed a rejection of > 98% to eosin Y (MW of 648 g/mol) while pure water, ethanol, and IPA permeances were 16.4, 3.3, and 1.4 LMH/bar at 20 bar, respectively. Moreover, they showed a superlative rejection of 92.1% to tetracycline, a smaller drug solute with a MW of 444 g/mol, in IPA solutions after thermal annealing at 120 °C for 40 min. Interestingly, the annealed MMMs still possessed a higher ethanol flux and solute rejections than the pristine P84 membrane. Besides, they also showed promising OSN performance in 72-h continuous tests. [ABSTRACT FROM AUTHOR]

This study reports the ultrasound-assisted improvements in biocatalytic activity and production of protease from organic solvent-tolerant, alkaliphilic Bacillus circulans MTCC 7942. The strain withstands 10 min ultrasound treatment (33 kHz); this treatment promotes the growth of bacterium. The protease production was improved by 1.5-fold on multiple ultrasound treatment at 0, 6, 12 h intervals. Although the substrate casein remains unaffected by ultrasound treatment (33 kHz, 10 min); the treatment had boosted the enzyme activity of purified protease . Also, the ultrasound treated purified protease showed enhancement in enzyme activity in presence of n-dodecane, n-octane, n-hexadecane, n-decane, xylene, butanol, toluene, pyridine and chloroform. [ABSTRACT FROM AUTHOR]

In this study, the gelatin, zein, and gelatin/zein films were fabricated by electrospinning and solvent casting, respectively. Scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy and water contact angle measurements were performed to characterize the morphology, molecular interactions, thermal behavior, and surface hydrophilicity of the electrospun and casted films. Results showed that the zein particles prevented the gelatin chains from aggregating intra-molecularly in the casted films due to heterogeneous mixing, while strong hydrogen bonding was formed in the nanofibrous film as a result of homogeneous mixing. Interestingly, the gelatin/zein nanofibrous film had a hydrophobic surface (water contact angle of 118.0°), while the casted gelatin/zein film had a hydrophilic surface (water contact angle of 53.5°). The confocal laser scanning microscopy observations suggested that the zein particles were well dispersed in the gelatin network to maintain the nanofibrous structures after immersion in water or ethanol, leading to the improved solvent resistance. [ABSTRACT FROM AUTHOR]

A novel bonding-induced emission (BIE) phenomenon of silyl-protected copper nanoclusters was observed and identified, and a new detection method for trace water in organic solvents was established based on a water-triggered BIE process. This assay employs simple and commercially available reagents and is capable of determining trace water at the ppm level. [ABSTRACT FROM AUTHOR]

An efficient approach involving surfactant treatment, or the modification and utilization of surfactants that naturally occur in algae (algal-based surfactants), was developed to assist in the extraction of lipids from wet algae. Surfactants were found to be able to completely replace polar organic solvents in the extraction process. The highest yield of algal lipids extracted by hexane and algal-based surfactants was 78.8%, followed by 78.2% for hexane and oligomeric surfactant extraction, whereas the lipid yield extracted by hexane and ethanol was only 60.5%. In addition, the saponifiable lipids extracted by exploiting algal-based surfactants and hexane, or adding oligomeric surfactant and hexane, accounted for 78.6% and 75.4% of total algal lipids, respectively, which was more than 10% higher than the lipids extracted by hexane and ethanol. This work presents a method to extract lipids from algae using only nonpolar organic solvents, while obtaining high lipid yields and high selectivity to saponifiables. [ABSTRACT FROM AUTHOR]

White-rot fungi (WRF) and their ligninolytic enzymes have been investigated for the removal of a broad spectrum of trace organic contaminants (TrOCs) mostly from synthetic wastewater in lab-scale experiments. Only a few studies have reported the efficiency of such systems for the removal of TrOCs from real wastewater. Wastewater derived organic and inorganic compounds can inhibit: (i) WRF growth and their enzyme production capacity; (ii) enzymatic activity of ligninolytic enzymes; and (iii) catalytic efficiency of both WRF and enzymes. It is observed that essential metals such as Cu, Mn and Co at trace concertation (up to 1 mM) can improve the growth of WRF species, whereas non-essential metal such as Pb, Cd and Hg at 1 mM concentration can inhibit WRF growth and their enzyme production. In the case of purified enzymes, most of the tested metals at 1–5 mM concentration do not significantly inhibit the activity of laccases. Organic interfering compounds such as oxalic acid and ethylenediaminetetraacetic acid (EDTA) at 1 mM concentration are potent inhibitors of WRF and their extracellular enzymes. However, inhibitory effects induced by interfering compounds are strongly influenced by the type of WRF species as well as experimental conditions ( e.g. , incubation time and TrOC type). In this review, mechanisms and factors governing the interactions of interfering compounds with WRF and their ligninolytic enzymes are reviewed and elucidated. In addition, the performance of WRF and their ligninolytic enzymes for the removal of TrOCs from synthetic and real wastewater is critically summarized. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium (SLE) of l -norvaline in three different binary solvents, including water + methanol, water + ethanol and water + 2-propanol, was determined by employing a gravimetric method over temperatures from 283.15 K to 318.15 K. It is found that the equilibrium solubility of l -norvaline in the mixed solvents increases with rising temperature at constant solvent composition and decreases with the increasing molar fraction of organic solvents. Moreover, the dissolving capacity of l -norvaline in the three binary solvent mixtures at constant temperature can be ranked as (methanol + water > ethanol + water > 2-propanol + water) in general. Furthermore, a model which can be called polar equation was applied to quantitatively describe the relationship between solubility and polarity of solvent mixtures. The results demonstrate that the increasing polarity of the binary solvents can enhance the solubility of l -norvaline. Besides, the experimental solubility was well correlated by the modified Apelblat equation, λh equation, and NRTL model, with the maximum ARD % values: 1.89%, 3.48%, and 6.42%, respectively. Additionally, the mixing thermodynamic properties of l -norvaline in three binary solvent mixtures were also discussed based on the NRTL model. Results show that the mixing processes of l -norvaline are endothermic and spontaneous. [ABSTRACT FROM AUTHOR]

The contamination of water by heavy metals has become one of the greatest threats to global ecological systems. Vaterite, in spite of the excellent performance to remove toxic metal ions, is difficult to be prepared with a large scale production, which limits its further industrial application. To this end, we developed a green and rapid approach to prepare in batch uniform porous vaterite/chitosan oligosaccharide (COS) hybrid microspheres (V-COS) at room temperature. Especially in the presence of 5 g L −1 COS, high vaterite content (nearly 100%) and large scale production of CaCO 3 microspheres were obtained within only 2 min without any other organic solvent. SEM images showed that an individual hybrid microsphere was composed of many nanoparticles, and TEM results demonstrated that these nanoparticles consisted of multiple nanocrystals. It was found that the concentration of COS and high shearing stirring were the key issues for the high production of V-COS. Based on the results the formation mechanism of V-COS was proposed. Their application for removal of lead and cadmium ions from aqueous solutions was investigated. The high and fast adsorption capacity for Pb 2+ and Cd 2+ ions were achieved with the adsorption amount up to 1884 and 156 mg/g within 6 min, respectively, which were much higher than that of rhombohedron CaCO 3 obtained without stirring (R-COS). The porous vaterite hybrid microspheres obtained with such large scale production has never been reported before, and this will lay foundation for its further wide applications. [ABSTRACT FROM AUTHOR]

Cerium doped zinc oxide (2 at. %) aerogels were synthesized in supercritical methanol and different supercritical mixture solvents (methanol-acetone and methanol-ethanol). The as-elaborated samples were analyzed without any additional heat or chemical treatments by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), optical absorption, photoluminescence (PL) and TGA techniques. The XRD results show that drying in solvents mixture enhances the crystalline quality and acts as a compression agent by exerting stress on the lattice parameters. SEM images demonstrate that the agglomeration rate of aerogel particles decreases when solvents mixture is used. TGA measurements showed the high purity of the samples. FTIR results showed a shift of Zn O bond indicating that supercritical solvent influences the number of Ce O Zn bonds at the surface of the crystallites. UV–vis characterization demonstrates that a band-to-band transition (3.34 eV) is observed only in the spectrum of the aerogel synthesized in supercritical acetone. The photoluminescence (PL) spectra exhibited different optical properties of the aerogels in violet-blue-green wavelengths region (350–530 nm). A blue-green emission located at 485 nm is observed only in methanol and acetone. The intensity of this band is sensitive to the supercritical organic solvent. [ABSTRACT FROM AUTHOR]

The solubility of cetilistat in neat solvents of acetone, isopropanol, acetonitrile and water were determined experimentally by using the isothermal dissolution equilibrium method within the temperature range from (278.15 to 323.15) K under atmospheric pressure of 101.1 kPa. At the fixed temperature, the mole fraction solubility of cetilistat was greater in acetone than in the other three neat solvents. They ranked as acetone > isopropanol > acetonitrile > water. The obtained solubilities were correlated with Apelblat equation. The largest value of relative average deviation was 0.86 × 10 − 2 , and of root-mean-square deviation, 15.55 × 10 − 4 . Furthermore, the preferential solvation parameters ( δx 1,3 ) of cetilistat in co-solvent mixtures of acetone (1) + water (2), isopropanol (1) + water (2) and acetonitrile (1) + water (2) were derived from their thermodynamic properties by means of the inverse Kirkwood–Buff integrals method. The values of δx 1,3 varied non-linearly with the co-solvent (1) proportion in all the aqueous mixtures. The preferential solvation parameter was negative in water-rich mixtures but positive in intermediate composition and co-solvent-rich mixtures. In the latter case, it was conjecturable that cetilistat was acting as a Lewis acid with co-solvent molecules. The co-solvent action might be related to the breaking of the ordered structure of water around the polar moieties of cetilistat which increased the solvation of this drug. The solubility data and thermodynamic study expanded the physicochemical information about cetilistat in binary solvent mixtures, which was required in the pharmaceutical and chemical industries to save time and money in the optimization of the solubilization and/or crystallization process designs. [ABSTRACT FROM AUTHOR]

Three spiropyran-4′,6′-dicarbonylazide molecules were synthesized for the covalent functionalization of the multiple-walled carbon nanotubes (MWCNTs) in a more straight and rigid connection mode without employing the key functional group for the automerization of spiropyran. The well solubility of MWCNTs and the solution stability were estimated in water and a series of common non-aqueous organic solvents. Spectroscopic properties have also been investigated. [ABSTRACT FROM AUTHOR]

High density polyethylene (HDPE) and polypropylene (PP) solubility in several pure and blend non-polar organic solvents was measured at 365-430 K temperature at atmospheric pressure, with polymer concentration of 0.5-25g in 100 ml of solvent. The activity coefficients were estimated depending on the experimental solubility results for all the polymer-solvent systems. A non-ideal equation combined with activity coefficient was developed based on the crystallinity. A new correlation equation was attained, which is based on the melting temperature and heat of fusion using SSPS software. These two equations were used to predict the solid-liquid experimental data for the binary system polymer-solvent. The distinction between the experimental and model data was assessed by using mean absolute deviation percentage (MAD %). The non-ideal equation based on crystallinity and the new correlations showed low MAD %, displaying a close match with the experimental data. [ABSTRACT FROM AUTHOR]

Dispersive liquid-liquid microextraction (DLLME) is a special type of microextraction in which a mixture of two solvents (an extracting solvent and a disperser) is injected into the sample. The extraction solvent is then dispersed as fine droplets in the cloudy sample through manual or mechanical agitation. Hence, the sample is centrifuged to break the formed emulsion and the extracting solvent is manually separated. The organic solvents commonly used in DLLME are halogenated hydrocarbons that are highly toxic. These solvents are heavier than water, so they sink to the bottom of the centrifugation tube which makes the separation step difficult. By using solvents of low density, the organic extractant floats on the sample surface. If the selected solvent such as undecanol has a freezing point in the range 10–25 °C, the floating droplet can be solidified using a simple ice-bath, and then transferred out of the sample matrix; this step is known as solidification of floating organic droplet (SFOD). Coupling DLLME to SFOD combines the advantages of both approaches together. The DLLME-SFOD process is controlled by the same variables of conventional liquid-liquid extraction. The organic solvents used as extractants in DLLME-SFOD must be immiscible with water, of lower density, low volatility, high partition coefficient and low melting and freezing points. The extraction efficiency of DLLME-SFOD is affected by types and volumes of organic extractant and disperser, salt addition, pH, temperature, stirring rate and extraction time. This review discusses the principle, optimization variables, advantages and disadvantages and some selected applications of DLLME-SFOD in water, food and biomedical analysis. [ABSTRACT FROM AUTHOR]

A new fluorescent tripod containing three symmetrical 1,8-naphthalimide units has been synthesized. The photophysical characteristics have been investigated in organic solvents of different polarity. The ability of the tripod to detect metal ions (Pb 2+ Zn 2+ , Ni 2+ and Cu 2+ ) has been investigated in acetonitrile solution. The influence of pH on the tripod fluorescence intensity has also been studied in an ethanol − water (1:4 v/v) solution. The antimicrobial activity of the new tripod was investigated against Gram-positive and Gram-negative bacteria and yeasts using the agar diffusion method. The antimicrobial effect of the new compounds was also investigated upon their deposition on cotton fabric. The chemical structure of the tripod as a determining factor for its antimicrobial activity was discussed. [ABSTRACT FROM AUTHOR]

Synthesis of magnetic iron oxide (Fe3−xO4) nanosheets using iron oleate complex via hydrothermal methods were investigated, and the obtained Fe3−xO4 nanosheets had 500 to 2000 nm in lateral size. Since the thickness of Fe3−xO4 nanosheets was 10 nm, the estimated aspect ratio was 50 to 200. On the other hands, Fe3−xO4 nanocubes are obtained only in solvothermal treatment. These results suggest that liquid-liquid interface between aqueous solution and non-polar organic solvent plays an important role to synthesize iron oxide nanosheets with large lateral dimensions. [ABSTRACT FROM AUTHOR]

Superhydrophobic and superoleophilic sponge was prepared by facile dip coating in a stearic acid (SA) solution and subsequent heat treatment. The obtained sponge exhibits excellent superhydrophobic stability and selectively sorption ability for oil pollutants on water surface. Also, the sponge is capable of separating huge amounts of oils from water continuously via a vacuum system and oil droplets in oil-in-water emulsions. After the separation by the coated sponge, the transparency for the emulsions ( n -Hexane-in-water and toluene-in-water) can increase to over 80% from below 14.7%. The oil sorption capacity of as-prepared sponge for various types of oils and organic solvents can reach 17.4–41.6 times of its own weight, and the absorbed oils are easy to be recovered by a simple squeezing process. Moreover, the recovered sponge can repeatedly absorb/desorb the oils for at least 100 times, demonstrating slightly decrease in sorption capacities and hydrophobicity. The proposed approach for fabricating superhydrophobic sponges is simple and inexpensive so that the as-prepared sponge has great potential as an efficient sorbent in oily wastewater filtration and oil spill clean-up. [ABSTRACT FROM AUTHOR]

A cellulase, En5H, from halophilic, alkalithermophilic Alkalilimnicola sp. NM-DCM1 was expressed and purified. En5H had maximal hydrolytic activity at 55 °C, pH 8.8, and 2.5 M NaCl. En5H is β-1,4 linkage-specific, hydrolyzing carboxymethyl cellulose, Avicel, cellobiose, and p-nitrophenyl β- d-glucopyranoside. En5H was resistant to inhibitors and organic solvents. The half-life of En5H was increased 16-43-fold when incubated in 20% ( v/ v) of ionic liquids (IL) at 55 °C in the presence of 2.5 M NaCl, and maximal hydrolytic activity of En5H in 10% ( v/ v) 1-allyl-3-methylimidazolium chloride and 1,3-dimethylimidazolium dimethyl phosphate was 122 and 110%, respectively, as compared with activity in buffer. A cellulase-IL system combining IL pretreatment and enzymatic saccharification was tested. With an enzyme load of 110 U/g rice straw, the conversion of rice straw cellulose and hemicellulose increased by 28% compared with unpretreated rice straw. En5H has potential for use in transformation of lignocellulose to glucose in a single-step process. [ABSTRACT FROM AUTHOR]

Pulsed-laser ablation of silicon (Si) was conducted in six different organic solvents using a nanosecond laser. Si nanoparticles (Si-NPs) that exhibited blue photoluminescence (PL) were generated in all the solvents, but a significant solvent dependence emerged: particle size, PL spectra, and PL quantum yield (QY). The results of solvent dependence were well characterized using an atomic ratio in a solvent molecule. The highest QY was observed for the smallest Si-NPs (ca. 2 nm) synthesized in 1-octyne. The QY was enhanced by aging in 1-octyne, and its mechanism was attributed to alkyl passivation of dangling bonds on the Si-NPs. [ABSTRACT FROM AUTHOR]

In this paper, a simple and non-poisonous “surfactant treatment” method to prepare graphene oxide (GO) in organic solvents with good dispersibility was presented. As the surfactant molecules, didodecyldimethyla-mmonium bromide (DDAB) was attached onto the GO sheets via ionic interactions by mild sonication, the obtained GO:DDAB nanocomposites were then blended into copolymer Poly(3-hexylthiophene-2,5-diyl) (P3HT) [6,6]:-Phenyl C 61 butyric acid methyl ester (PC 61 BM) as the active layer to fabricate bulk-heterojunction (BHJ) organic solar cells ITO/PEDOT:PSS/P3HT:PC 61 BM:(GO:DDAB)/Ca/Al. The concentration of GO:DDAB in the active layer, a maximum power conversion efficiency (PCE) of 3.67% was obtained by blending 0.5 mg/mL GO:DDAB in the active layer, showing an efficiency increment of 13.35% as compared with that of the control device without doping GO:DDAB. The optimized OPVs with PTB7:PC 71 BM by adding GO:DDAB shows the PCE of 7.96%. Therefore, it paves a way to get high efficiency organic photovoltaic cells by directly blending surfactant-treated graphene oxide in organic solvent. [ABSTRACT FROM AUTHOR]

The lithium-ion batteries are widely used in rechargeable electronic devices. The current challenges are to improve the capacity and safety of these systems in view of their development to a larger scale, such as for their application in electric and hybrid vehicles. Lithium-ion batteries use organic solvents because of the wide operating voltage. The corresponding electrolytes are usually based on combinations of linear, cyclic alkyl carbonates and a lithium salt such as LiPF 6 . It has been reported that in abusive thermal conditions, a catalytic effect of the cathode materials lead to the formation fluoro-organics compounds. In order to understand the degradation phenomenon, the study at 240 °C of the interaction between positive electrode materials (LiCoO 2 , LiNi 1/3 Mn 1/3 Co 1/3 O 2 , LiMn 2 O 4 and LiFePO 4 ) and electrolyte in dry and wet conditions has been realized by an original method which consists in analyzing by mass spectrometry in real time the volatile molecules produced. The evolution of specific gases channels coupled to the NMR reveal the formation of rarely discussed species such as 2-fluoroethanol and 1,4-dioxane. Furthermore, it appears that the presence of water or other protic impurities greatly influence their formation. [ABSTRACT FROM AUTHOR]

A non-covalent self-assembled chiral alanyl aminopyridine ligand exhibits supramolecular chirality in solution, independent of the organic solvent used. The supramolecular chirality of the assemblies is completely inverted by complexation to zinc ions. To date, such a supramolecular metal–ligand system has not been reported in the literature. [ABSTRACT FROM AUTHOR]

The application of homogeneous transition metal catalysts offers various advantages for chemical processes, such as mild reaction conditions and high selectivity. The main drawback is the difficult recovery of these precious catalysts, so that a small loss of catalyst can cause economic insufficiency of a chemical process. Our approach for overcoming this challenge is the application of two different catalyst recovery techniques, which are combined in a so-called hybrid separation process. Here, a thermomorphic solvent system is used for the recovery of the precious rhodium catalyst in a first stage, and a subsequent organic solvent nanofiltration unit is used in a second stage. [ABSTRACT FROM AUTHOR]

The severe environmental and ecological problems, derived from oil spills and organic solvents leakage, have occurred in many parts of the world. It is urgent to seek appropriate ways to resolve oily wastewater and organic solvent pollution. A versatile oil-absorbing material which can separate the oily wastewater effectively and quickly is in high demanded for this issue. In this work, we report a facile and inexpensive to fabricate an effective and recyclable oil-absorbent, namely MnO 2 nanowires/polyurethane (PU) foam composites, using a PU sponge as a porous substrate and MnO 2 nanowires as modifiers. The hydrothermal method is employed to synthesize MnO 2 nanowires and then foaming technology is used to fabricate MnO 2 nanowires/PU foam composites. In order to enhance the hydrophobic and oleophilic properties, the surfaces of MnO 2 nanowires are chemically modified using silane coupling agent (KH 570). The present MnO 2 nanowires/PU foam composites not only effectively separate oils from water as expected, but also possess a very high absorption capacity for the removal of organic solvents from water up to 40.15 times its own weight. More importantly, the obtained MnO 2 nanowires/PU foam composites is demonstrated to have excellent oil recoverability and absorbent regenerability, making them versatile and comprehensive absorbents to satisfy various practical oily wastewater and organic solvent separation requirements. [ABSTRACT FROM AUTHOR]

The system constants of the solvation parameter model are used to prepare system maps for the retention of small neutral compounds on a biphenylsiloxane-bonded superficially porous silica stationary phase (Kinetex Biphenyl) for aqueous-organic solvent mobile phases containing 10–70% (v/v) methanol or acetonitrile. The retention properties of the biphenylsiloxane-bonded phase are shown to be complementary to an octadecylsiloxane-bonded silica (Kinetex C-18) and a pentafluorophenylpropylsiloxane-bonded silica stationary phases (Discovery HS F5). The retention properties of the Kinetex Biphenyl column are similar to an ether-linked phenylpropylsiloxane-bonded silica phase (Synergi Polar RP) with only small differences in relative retention. [ABSTRACT FROM AUTHOR]

A procedure has been proposed for the synthesis of ( S)-(-)-1-phenylethanol, an important building block for the preparation of medicinal agents possessing antidiabetic, antidepressant, and antirabic activity, as well as of antifeedants and antiparasitic, antimicrobial, and antifungal metabolites, by enantioselective bioreduction of acetophenone. Different exogenous reducing agents (propan-2-ol, ethanol, and glucose) were tried to improve the yield of the target product and its enantiomeric purity. [ABSTRACT FROM AUTHOR]

We report photochromic donor–acceptor Stenhouse adducts (DASAs) capable of fully reversible photoisomerization with visible light in organic solvents including chloroform, acetonitrile and benzene. The rates of photoisomerization and thermal reversion can be tuned by altering the electronics of the donor adduct. X-Ray crystallography and photo-NMR experiments unambiguously establish molecular structures. [ABSTRACT FROM AUTHOR]

A benzyl-ether-type ionic-liquid tag (IL tag) was developed and applied for electrochemical glycosylation. The IL tag was shown to display multifunctional roles in the glycosylation: the tag in thioglycosides worked as both an intramolecular electrolyte for the anodic oxidation and a stereo-controlling group; it also enabled easy extraction of the products after the reaction. [ABSTRACT FROM AUTHOR]

Electrochemical analyses of alkyl, phenyl, and thienylboronic acids were comparatively studied by cyclic voltammetric measurements in the absence and presence of fluoride ions, and we found remarkable negative shift of their oxidation potentials in the presence of fluoride ions compared with those in the absence of fluoride ions. Such negative shift seems to be derived from the formation of negative charged boron-ate complex with fluoride ions. Anodic fluorination of 2-acetyl-5-thienylboronic acid was carried out to provide mono- and trifluoro products eliminating a boryl group in moderate yields. These results clearly indicate that a boryl group with fluoride ions is a good electroauxiliary. [ABSTRACT FROM AUTHOR]

We herein report the effects of the following variables on demulsification using an alternating electric field: (1) type and volume fraction of an organic solvent, and (2) type and ionic strength of an electrolyte in water. Ethylbenzene, toluene, o -xylene, m -xylene, p -xylene, cyclohexane, and n -hexane were employed as organic solvents. The effect on demulsification of either KCl or CaCl 2 addition to the aqueous phase was also examined. We observed that a square waveform alternating electric field was more effective than a sine waveform. In addition, the demulsification rate varied significantly upon altering the volume fraction of the organic solvent and the ionic strength of the electrolyte. Demulsification using an alternating electric field was effective for W/O type emulsions. Demulsification was promoted using an organic solvent with greater relative permittivity. [ABSTRACT FROM AUTHOR]

Five new urethane groups containing monomers 1- 5, acetylated glycerol dimethacrylate (AGDMA), and glycerol trimethacrylate (GTMA) are synthesized as alternative diluents to triethylene glycol dimethacrylate (TEGDMA) for dental resins or composites. The synthesized monomers are characterized by means of 1H NMR, 13C NMR, and IR spectroscopy. The secondary acrylamide group containing hybrid monomers 1 and 2 are solids. However, the monomers 3- 5, AGDMA and GTMA are colorless and relatively low-viscosity liquids. They are not mutagenic in the Ames test and show a lower cytotoxicity and a lower polymerization shrinkage compared to TEGDMA. The tertiary amide group containing crosslinker 3 shows a significantly higher photopolymerization rate compared to that of TEGDMA in the presence of the monomolecular Ge-based photoinitiator Ivocerin. The synthesized diluents are evaluated in experimental dental formulations for resins, cements, and direct filling composites using a conventional binary camphorquinone/amine photoinitiator. [ABSTRACT FROM AUTHOR]