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A super-lightweight, bidirectionally ordered, three-dimensional porous hybrid graphene aerogel (HGA) was prepared and evaluated. The preparing parameters involved obtaining a uniform suspension through mechanical stirring for 3 h, followed by ultrasonic dispersion for 30 min, maintaining pH at 9. The suspension then underwent liquid nitrogen pre-freezing, vacuum freeze-drying for 48 h and hydrazine hydrate vapor reduction at 90 ℃ for 24 h. Furthermore, the microstructure, the adsorption and reusability properties of HGA were evaluated. The results demonstrated that HGA could adsorb organic solvents up to 159 times its own weight and effectively separate oil from water. The HGA exhibited excellent mechanical properties, releasing 98% of its shape with a 30% compression ratio under a stress 2653 times its own weight. Additionally, after 10 adsorption-combustion cycles, the adsorption capacity decreased by only 3.67%, and the mass retention rate exceeded 90%, indicating good reusability and flame-retardant properties. [ABSTRACT FROM AUTHOR]

C–H bond activation under mild conditions remains a great challenge in the chemical industry, while catalytic cyclohexane oxidation is inefficient and often requires organic solvents and strong oxidants. This study constructed a C3N4/WO3 Z-type heterojunction catalyst to efficiently convert cyclohexane into cyclohexanone and cyclohexanol (KA oil) through aqueous phase oxidation by O2 under visible light irradiation. With strong redox performance and high photogenerated carrier separation ability, the proposed composite catalyst can produce the key active species for cyclohexane oxidation in the H2O–O2 system. The reaction mechanism was clarified through experiment and DFT theory calculation. Cyclohexane was converted into cyclohexyl radical under the action of ·OH, and ·O2− converted most products into cyclohexanone. The catalyst can be recycled under optimized process conditions while reaching a KA oil yield of 139.73 μmol g−1 h−1 and a selectivity of 93.1%. [ABSTRACT FROM AUTHOR]

The first part of the review provides general information about the solvent extraction of organic compounds from solid samples and discusses various methods for its implementation: extraction in a Soxhlet apparatus, ultrasonic extraction, microwave-assisted extraction. Based on an analysis of review papers, information on the features of sample preparation using these methods is systematized, experimental parameters affecting extraction efficiency are considered, and examples of using these methods for isolating organic compounds in the analysis of solid environmental samples, food products, and plants are given. [ABSTRACT FROM AUTHOR]

Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. In contrast, aerobic biological activities combined with mechanical stimulus promote tissue regeneration and repair in various organs. A synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization will afford similar robustness in polymeric materials. Herein, aerobic mechanochemical reversible-deactivation radical polymerization was developed by the design of an organic mechano-labile initiator which converts oxygen into activators in response to ball milling, enabling the reaction to proceed in the air with low-energy input, operative simplicity, and the avoidance of potentially harmful organic solvents. In addition, this approach not only complements the existing methods to access well-defined polymers but also has been successfully employed for the controlled polymerization of (meth)acrylates, styrenic monomers and solid acrylamides as well as the synthesis of polymer/perovskite hybrids without solvent at room temperature which are inaccessible by other means. Polymer materials suffer mechano-oxidative deterioration or degradation in the presence of molecular oxygen and mechanical forces. Here the authors demonstrate a synthetic approach in which molecular oxygen and mechanical energy synergistically initiate polymerization and affords robustness in polymeric materials. [ABSTRACT FROM AUTHOR]

Metabolite extraction is the critical first-step in metabolomics experiments, where it is generally regarded to inactivate and remove proteins. Here, arising from efforts to improve extraction conditions for polar metabolomics, we discover a proteomic landscape of over 1000 proteins within metabolite extracts. This is a ubiquitous feature across several common extraction and sample types. By combining post-resuspension stable isotope addition and enzyme inhibitors, we demonstrate in-extract metabolite interconversions due to residual transaminase activity. We extend these findings with untargeted metabolomics where we observe extensive protein-mediated metabolite changes, including in-extract formation of glutamate dipeptide and depletion of total glutathione. Finally, we present a simple extraction workflow that integrates 3 kDa filtration for protein removal as a superior method for polar metabolomics. In this work, we uncover a previously unrecognized, protein-mediated source of observer effects in metabolomics experiments with broad-reaching implications across all research fields using metabolomics and molecular metabolism. Metabolite extraction with organic solvents is assumed to remove/denature proteins. Here, the authors uncover a vast landscape of >1,000 proteins in metabolite extracts. These proteins can retain catalytic activity and drive post-extraction metabolite changes, obscuring biological interpretation. [ABSTRACT FROM AUTHOR]

The biochemical composition and bioavailability of particulate organic matter (POM) were studied in relation to abiotic (water column stratification, macronutrient concentrations) and biotic factors (phytoplankton biomass and functional groups) in the open Ross Sea and coastal area of Terra Nova Bay, Antarctica, during the austral summer 2017. The presence of different sub-systems was highlighted by spatial and temporal variations of all the considered variables, characterised by higher concentrations of particulate organic carbon and nitrogen in Terra Nova Bay, where diatoms dominated, while in the open Ross Sea was higher the contribution of haptophytes (Phaeocystis antarctica Karsten, 1905). The southernmost Ross Sea was characterised by significantly higher concentrations of carbohydrates in the entire water column. High lipid contribution and low photosynthetic activity indicated aged POM, suggesting that POM was composed mainly by the remnants of previous haptophytes production. The higher lability of the carbohydrates indicated that an increase of haptophytes in the area could alter the biogeochemical C cycle, reducing the storage of refractory carbon in the depths, and favouring the transfer and respiration of C in the trophic web, with a decrease of export rate in the Ross Sea. [ABSTRACT FROM AUTHOR]

The use of deicers in urban areas, on runways and aircrafts has raised concerns about their environmental impact. Understanding the ice-melting mechanism is crucial for developing environmentally friendly deicers, yet it remains challenging. This study employs machine learning to investigate the ice penetration capacity (IPC) of 21 salts and 16 organic solvents as deicers. Relationships between their IPC and various physical properties were analysed using extreme gradient boosting (XGBoost) and Shapley additive explanation (SHAP). Three key ice-melting mechanisms were identified: (1) freezing-point depression, (2) interactions between deicers and H2O molecules and (3) infiltration of ions into ice crystals. SHAP analysis revealed different ice-melting factors and mechanisms for salts and organic solvents, suggesting a potential advantage in combining the two. A mixture of propylene glycol (PG) and sodium formate demonstrated superior environmental impact and IPC. The PG and sodium formate mixture exhibited higher IPC when compared to six commercially available deicers, offering promise for sustainable deicing applications. This study provides valuable insights into the ice-melting process and proposes an effective, environmentally friendly deicer that combines the strengths of organic solvents and salts, paving the way for more sustainable practices in deicing. [ABSTRACT FROM AUTHOR]

Despite their widespread applications in sectors such as pulp and paper, textile, food and beverage, pharmaceuticals, and biofuel production, laccases encounter challenges related to their activity and stability under varying reaction conditions. This review accumulates data on the complex interplay between laccase characteristics and reaction conditions for maximizing their efficacy in diverse biotechnological processes. Benefits of organic media such as improved substrate selectivity and reaction control, and their risks such as enzyme denaturation and reduced activity are reported. Additionally, the effect of reaction conditions such as pH and temperature on laccase activity and stability are gathered and reported. Sources like Bacillus pumilus, Alcaligenes faecalis, Bacillus clausii, and Bacillus tequilensis SN4 are producing laccases that are both thermo-active and alkali-active. Additionally, changes induced by the presence of various substances within reaction media such as metals, inhibitors, and organic solvents are also reported. Bacillus pumilus and Bacillus licheniformis LS04 produce the most resistant laccases in this case. Finally, the remarkable laccases have been highlighted and the proper laccase source for each industrial application is suggested. [ABSTRACT FROM AUTHOR]

Different methods were used to extract C-phycocyanin from Arthrospira platensis, alone or in synergy (freezing, incubation, ultrasounds, deep eutectic solvents). Freezing or Freeze-drying spirulina allows a highly facilitated rupture of the cell membranes. Incubation in water allows then a quick release of C-PC and other phycobiliproteins at 45 °C (2 h) while it takes less than 8 h at 35 °C and 25–30 h at ambient temperature. In addition to microscopic observation, the evolution of solutes concentration with incubation time confirms that hydrosoluble pigments are first preferentially released relatively to chlorophyll which requires deeper collapse of the spirulina cells. Use of ultrasounds allows an extraction of the spirulina content in 15 min of treatment with a high C-PC extraction yield (> 200 mg/g) and good protein purity (around 0.7). Ethyl acetate, ethanol and a mixture of these solvents give good extraction yields of chlorophyll (around 21 mg/g). C-PC extraction yield is yet then decreased due to a denaturation of the hydrated pigment. Fructose can be used to prevent denaturation by both organic solvent and freezing/freeze-drying. The use of deep-eutectic solvents is not recommended here as no better yield or selectivity are achieved compared to extraction in buffered water. [ABSTRACT FROM AUTHOR]

In this study, the effect of polarity and hydrogen bonding ability of solvents on the absorption spectrum of Congo red was investigated. UV–Visible absorption spectra were recorded in eight neat solvents and four aqueous binary solutions of methanol, ethanol (as HBD solvents), and dimethylsulfoxide and dioxane (as HBA solvents). Congo red has two absorption maxima in the range (250–700 nm) that have been assigned to the azo and hydrazo systems. Molar transition energy (ET) values of Congo red in different solvents were correlated with the solvent parameters using linear solvation energy relationships. Multiparameter analysis shows the dependence of the electronic spectra of Congo red on the non-specific and specific interactions. Preferential solvation was observed in all binary mixtures when ET plotted as a function of mole fraction of organic solvents. The results showed that the Congo red was solvated by water–organic solvent complex species in all binary mixtures except in case of aqueous-ethanol mixtures, whose preferred solvation by ethanol in all mole fractions with f12/2 and f12/1 values less than unity. The dual-parameters model is a powerful tool for explaining binary mixture data with Kamlet–Taft parameters. The findings indicated that the HBD and HBA were responsible for the solvatochromism of the binary mixtures. [ABSTRACT FROM AUTHOR]

This study uses an optical sensor utilizing a manganese metal–organic framework (Mn-MOF) to detect tetracycline in wastewater. tetracycline was directly detected through fluorescence quenching with the dispersion of Mn-MOF in an ethanol solution, enabling direct tetracycline detection. The sensor has a notable detection limit of 66.39 nM and can detect tetracycline in the linear detection range spanning from 0.0032 to 0.43 µM. It has been found that Mn-MOF demonstrated excellent selectivity for tetracycline in the presence of other antibiotics. This selectivity suggests promising applications for environmental monitoring, showing the sensor's potential in effectively quantifying tetracycline amidst complex matrices found in wastewater. This sensor emerges as a crucial advancement in remediation strategies and environmental monitoring by addressing the challenge of tetracycline contamination. Its selectivity, sensitivity, and ability to operate within complex environments marks a significant step forward in developing efficient and reliable detection methods for tetracycline detection in wastewater and environmental protection. [ABSTRACT FROM AUTHOR]

A semiorganic lithium para-nitrophenolate dihydrate (LiPNP·2H2O) nonlinear optical crystal with a dimension of 18 × 11 × 4 mm 3 has been grown by slow evaporation method in a rapid growth period of 20 days by using ethanol as solvent. Powder X-ray diffraction studies revealed the crystal belong to monoclinic crystal system with space group of P21. The optical transmission study revealed a wider transparency with the lower cut-off wavelength of 457 nm and an optical bandgap of 2.91 eV. The emission properties, functional groups, and mechanical stability of the obtained crystal were determined by Photoluminescence, FTIR spectral analysis, and Vickers's microhardness measurements. The electrical conductivity and thermal stability were examined through electrochemical impedance (EIS) and TG-DTA analysis. The Second harmonic generation efficiency (SHG) of the crystal was found to be 2.6 times greater than that of the standard KDP. Therefore, LiPNP·2H2O crystal with high SHG efficiency could be a suitable candidate for nonlinear optical and optoelectronic device applications due to its optical, thermal, and mechanical properties. [ABSTRACT FROM AUTHOR]

Context: One of the prevalent methods for evaluating separation performance is to predict the interactions of solvent and solute molecules. The infinite dilution activity coefficient, Gibbs free energy, and sigma profiles provided insights into the solubilization of a solute and revealed the intensity of the solution's molecular interactions. The effective thermodynamic tools (infinite dilution activity coefficient, Gibbs free energy) were evaluated for predicting the efficiency of 18 polar and non-polar organic solvents in rubber seed oil (RSO) extraction. An infinite dilution activity coefficient was computed to evaluate the solubility of the rubber seed oil model compound (linoleic acid) in the organic solvents. Gibbs free energy was evaluated to show the energy change associated with the molecules mixing process and forecast the miscibility of linoleic acid molecules in the solvents. Moreover, the study examined the sigma profiles and sigma surfaces of organic solvents and linoleic acid to acquire a deeper insight into their similarities and how they interact molecularly. According to the computational prediction and experimental verification, the thermodynamic properties of Gibbs free energy and activity coefficient proved to be highly effective tools for screening polar and moderately polar solvents, predicting the molecular interactions with solute. Whereas the sigma profile and sigma surface were found to be the most efficient tools for evaluating the efficacy of non-polar solvents. Solvents with moderate polarity, such as tetrahydrofuran and diethyl ether, as well as non-polar solvents like pentane, heptane, and n-hexane, proved to be effective and favorable for oil extraction, resulting in the highest oil yields of approximately 27.0%. Overall, the COSMO-RS method demonstrates its utility in estimating the solubility of RSO in organic solvents, enabling early identification of the most effective solvent. Methods: The initial geometry optimization of every component was conducted through density functional theory (DFT) using TmoleX software. A single-point density functional theory (DFT) computation using Becke Perdew 86 (BP86) and the Triple-Zeta Valence Potential (TZVPD) was performed to produce.cosmo files. COSMO-RS calculations were performed by applying the parameterization file BP_TZVPD_FINE_19.ctd using COSMOthermX software. The practical extraction of oil from plant seeds was performed using a sonicator bath to verify the accuracy of the COSMO-RS predictions. [ABSTRACT FROM AUTHOR]

In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42−), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42− was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly. [ABSTRACT FROM AUTHOR]

In this work, in situ sol–gel strategy was used to introduce silica gel in polyacrylonitrile (PAN) membrane pores, by which the pore structure of organic solvent nanofiltration (OSN) membrane prepared with thermal crosslinking was maintained well. The chemical structure, microstructure and morphology changes of membrane during sol–gel and thermal crosslinking were systematically studied by FTIR, XPS, XRD and SEM. Benefitting from the introduction of silica gel, the fusion of membrane pore structure during thermal crosslinking was effectively inhibited by supporting the pore with silica gel. Therefore, the permeances of the thermally crosslinked membranes supported by in situ silica gel were greatly improved. Furthermore, the thermally crosslinked membrane showed excellent stability of OSN performance due to the generated ladder structure of membrane during thermal crosslinking. This work showed that in situ silica gel supporting is a promising strategy to stabilize the pore structure of PAN membrane during thermal crosslinking. [ABSTRACT FROM AUTHOR]

Silicon and silicon-based materials are among the important modern materials with application in many fields of technology from electronics to energy materials. For some applications, for example the use of Si in Li-ion batteries, nanometer-sized dimensions are required. A cost-effective, environmentally sustainable, scalable, and versatile formation of functional Si films and materials is therefore of large interest. In this work, we report on the electrodeposition of amorphous silicon-based films onto planar and onto nanoporous copper substrates using different organic electrolytes. The morphology and composition of the Si-based coatings are dependent on the solvent used for electrodeposition. Acetonitrile, as a low viscosity solvent, leads to the faster formation of thicker, mostly metallic, and homogeneous electrodeposited Si films. Propylene carbonate, a higher-viscosity solvent generates thinner and more heterogeneous coatings. The Si electrodeposition presented in this work could be transferred onto other complex substrate morphologies, with potential applications in the fields of heterogeneous photocatalysis or energy storage. [ABSTRACT FROM AUTHOR]

Xylanases from thermophilic fungi have a wide range of commercial applications in the bioconversion of lignocellulosic materials and biobleaching in the pulp and paper industry. In this study, an endoxylanase from the thermophilic fungus Rasamsonia composticola (XylRc) was produced using waste wheat bran and pretreated sugarcane bagasse (PSB) in solid-state fermentation. The enzyme was purified, biochemically characterized, and used for the saccharification of sugarcane bagasse. XylRc was purified 30.6-fold with a 22% yield. The analysis using sodium dodecyl sulphate–polyacrylamide gel electrophoresis revealed a molecular weight of 53 kDa, with optimal temperature and pH values of 80 °C and 5.5, respectively. Thin-layer chromatography suggests that the enzyme is an endoxylanase and belongs to the glycoside hydrolase 10 family. The enzyme was stimulated by the presence of K+, Ca2+, Mg2+, and Co2+ and remained stable in the presence of the surfactant Triton X-100. XylRc was also stimulated by organic solvents butanol (113%), ethanol (175%), isopropanol (176%), and acetone (185%). The Km and Vmax values for oat spelt and birchwood xylan were 6.7 ± 0.7 mg/mL, 2.3 ± 0.59 mg/mL, 446.7 ± 12.7 µmol/min/mg, and 173.7 ± 6.5 µmol/min/mg, respectively. XylRc was unaffected by different phenolic compounds: ferulic, tannic, cinnamic, benzoic, and coumaric acids at concentrations of 2.5–10 mg/mL. The results of saccharification of PSB showed that supplementation of a commercial enzymatic cocktail (Cellic® CTec2) with XylRc (1:1 w/v) led to an increase in the degree of synergism (DS) in total reducing sugar (1.28) and glucose released (1.05) compared to the control (Cellic® HTec2). In summary, XylRc demonstrated significant potential for applications in lignocellulosic biomass hydrolysis, making it an attractive alternative for producing xylooligosaccharides and xylose, which can serve as precursors for biofuel production. [ABSTRACT FROM AUTHOR]

A robust, stability-indicating, and eco-friendly proton nuclear magnetic resonance (1H-qNMR) method was developed for the concurrent determination of three 1,4-benzodiazepines (BDZs), namely diazepam (DZP), alprazolam (ALP), and chlordiazepoxide (CDP) and their common impurity, synthesis precursor, and degradation product; 2-amino-5-chlorobenzophenone (ACB). In the present method, a novel approach was developed for composing a green and cost-efficient solvent system as an alternative to the common NMR organic solvents utilizing 0.3 M sodium dodecyl sulfate prepared in deuterated water. The conducted method is characterized by simplicity with no need for sample pretreatment or labeling. Phloroglucinol was used as an internal standard. The chosen signals for the determinations of ALP, CDP, DZP and ACB were at 2.35 ppm (singlet), 2.84 ppm (singlet), 3.11 ppm (singlet), and 6.90 ppm (doublet of doublet), respectively. The proposed method possessed linearity over the concentration range of 0.25–15.0 mg ml−1 for DZP, ALP, CDP and of 0.5–25.0 mg ml−1 for ACB with LOD values of 0.06, 0.03, 0.07 and 0.16 mg ml−1 respectively, and LOQ values of 0.18, 0.09, 0.21 and 0.49 mg ml−1, respectively. Accuracy of the method was evidenced by excellent recovery% (99.57–99.90%) and small standard deviation (≥ 1.10) for the three analyzed drugs. Intra- and inter-day precision were determined with coefficient of variation ranging from 0.12 to 1.14 and from 0.72 to 1.67, respectively. For the studied compounds, appraisal of the method greenness was achieved via four approaches: Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), Analytical greenness metric (AGREE), and RGB Additive Color Model. The results proved that the proposed method has the privilege of being a green analytical method. [ABSTRACT FROM AUTHOR]

A framework was developed to evaluate and compare cleaning systems and cleaning system delivery methods, collectively referred to as varnish removal methods, within art conservation practice. This framework was applied to two water-based cleaning systems, optimised for the removal of dammar varnish from an artificially aged brown earth oil paint, including the surfactant-containing microemulsion, Polar Coating B (from the Nanorestore Cleaning series) delivered via the chemical gel, Higher Water Retention (HWR) (from the Nanorestore Gel Dry series), and a surfactant-free microemulsion delivered via the microfiber cloth, Evolon. In addition, two water-based systems and one organic solvent were used to remove dammar varnish from an artificially aged lead white oil paint sample, including a xanthan gum-stabilised emulsion delivered via a synthetic brush, a surfactant-free microemulsion delivered via cotton swab rolling, and 2-propanol solvent delivered via cotton swab rolling. The evaluation framework was thus applied to two different oil paints, with different sensitivities to cleaning. Through this work, the comparative advantages and disadvantages of the varnish removal methods were demonstrated. Notably, cleaning system compatibility with multiple delivery methods afforded greater versatility, including for reducing unwanted interactions between the cleaning system and oil paint. In addition, a surfactant-free microemulsion proved to be a promising, clearance-free, inexpensive, and modifiable option within current offerings for largely water-based methods for varnish removal. [ABSTRACT FROM AUTHOR]

Four simple, sensitive, economical, and eco-friendly spectrophotometric and spectrofluorimetric methods for the assay of erdosteine (ERD) in bulk and dosage form have been developed and validated as per the current ICH guidelines. Method I involved the addition of the powerful oxidizing agent, potassium permanganate to ERD and measuring the oxidation product at 600 nm. Another oxidizing agent; ceric ammonium sulfate was used in Method II where ERD is oxidized resulting in a decline in the absorbance intensity of cerium (IV) ions, measured at 320 nm. Similarly, Method III employed the use of ceric ammonium sulfate, However, the fluorescence intensity of the resulting cerium (III) ions was recorded at λex/λem 255/355 nm, respectively. Whereas in Method IV, ERD was added to acriflavine leading to a proportional decrease in its native fluorescence. Various reaction conditions affecting the intensity of measurement were attentively investigated, optimized, and validated. All the suggested methods did not require any tedious extraction procedures nor organic solvents. The implementation of the proposed methods in ERD assay resulted in linear relationships between the measured signals and the corresponding concentrations of ERD in the range of 1–6, 0.1–1.0, 0.01–0.1, and 10–100 μg/mL with LOD values 0.179, 0.024, 0.0027 and, 3.2 μg/mL for methods I, II, III and IV respectively. The suggested methods were successfully applied to ERD analysis in pure form and in commercial capsules. Furthermore, the eco-friendliness of the proposed methods was thoroughly checked using various greenness testing tools. Lastly, this work, not only presents highly sensitive, green, mix-and-read methods for ERD determination, but also, describes the determination of ERD spectrofluorimetrically for the first time in the literature. [ABSTRACT FROM AUTHOR]

A series of Mn2+ -doped hybrid perovskites MAPb1-xMnxHal3 (MA = CH3NH3, Hal = Cl and Br in different ratios, x = 0.33, 0.5, 0.67, 0.8) was obtained for the first time by mechanochemical synthesis. It is shown that materials obtained retain the perovskite structure even at the highest content of manganese ions (x = 0.8), and their structural and optical characteristics are mainly determined by the Cl/Br ratio. It is established that dispersions in toluene and nanocomposite films in polystyrene exhibit the intense photoluminescence (PL) due to the formation of pseudo-2D nanoparticles as a result of the ultrasonic disintegration of powders in an organic solvent. It is shown that the PL spectra of dispersions and nanocomposite films based on MAPb1–xMnxCl3 are characterized by the appearance of an additional emission band from Mn2+ ions in the red region of the spectrum, due to which it is possible to increase the PL quantum yield from 0.2% (for the undoped sample) to 6.3% (films) and 10.2% (dispersions). [ABSTRACT FROM AUTHOR]

Density and viscosity measurements were carried out at 25 °C (298.15 K) on six binary di(or tri)glyme/organic carbonate (dimethylcarbonate, ethylene carbonate or propylene carbonate) systems and on multicomponent systems containing di(or tri)glyme/ organic carbonate mixtures. The effect of the organic carbonate composition on the excess weight volume (VwE), the deviation viscosity ( Δ η ), the partial weight and apparent weight volumes of glymes is interpreted in terms of competitive interactions and/or of differences in size or shape between glymes and organic carbonates. In addition, a model, based on viscosity data, is developed for the first time to determine the hydrodynamic volumes of glymes. The comparison of hydrodynamic volumes with Van der Waals volumes makes it possible to highlight and quantify the possible interactions between glymes and pure organic carbonates, and the association of triglyme molecules in organic carbonate EC/PC mixtures. The effect of LiPF6 and NaPF6 salts at 1 mol⋅L−1 in the glyme/organic carbonate mixtures appears to significantly reduce the volumes of glymes. By this, the strong interactions between salts and glymes are shown. [ABSTRACT FROM AUTHOR]

Al-rich waste pharmaceutical blisters (WPBs) have a multi-layer structure that contains aluminum and polymer-based fractions. Although the aluminum mass in WPBs is less than typical aluminum packaging products such as beverage cans, establishing a feasible recycling procedure is possible by separating the fractions to recover both metal and plastic. Hydrometallurgical methods are mostly preferred for the separation of aluminum and plastic in multi-layered structures. This work reports the characterization of Al-rich WPBs and the separation behavior of aluminum and plastic layers. The effects of hydrochloric acid, acetic acid, formic acid, sulfuric acid, ethanol, acetone, and organic solvent (benzene–ethanol–water) on the separation behavior of layers were studied at different temperatures. Furthermore, the recycling yield of the aluminum fraction was experimentally assessed. [ABSTRACT FROM AUTHOR]

The identification and applicability of bacteria are inconclusive until comprehended with genomic repositories. Our isolate, Exiguobacterium sp. TBG-PICH-001 exhibited excellent halo- and organic solvent tolerance with simultaneous production of alkaline protease/s (0.512 IU/mL). The crude protease (1 IU) showed a 43.57% degradation of whey protein. The bulk proteins in the whey were hydrolyzed to smaller peptides which were evident in the SDS-PAGE profile. With such characteristics, the isolate became interesting for its genomic studies. The TBG-PICH-001 genome was found to be 3.14 Mb in size with 17 contigs and 47.33% GC content. The genome showed 3176 coding genes, and 2699 genes were characterized for their functionality. The Next-Generation-Sequencing of the genome identified only the isolate's genus; hence we attempted to delineate its species position. The genomes of the isolate and other representative Exiguobacterium spp. were compared based on orthologous genes (Orthovenn2 server). A pan-genomic analysis revealed the match of TBG-PICH-001 with 15 uncharacterized Exiguobacterium genomes at the species level. All these collectively matched with Exiguobacterium indicum, and the results were reconfirmed through phylogenetic studies. Further, the Exiguobacterium indicum genomes were engaged for homology studies rendering 11 classes of protease genes. Two putative proteases (Zinc metalloprotease and Serine protease) obtained from homology were checked for PCR amplification using genomic DNA of TBG-PICH-001 and other Exiguobacterium genomes. The results showed amplification only in the Exiguobacterium indicum genome. These protease genes, after sequencing, were matched with the TBG-PICH-001 genome. Their presence in its whole genome experimentally validated the study. [ABSTRACT FROM AUTHOR]

A simple, inexpensive, reliable and environmentally friendly procedure based on ultrasound-assisted extraction combined with ultrasound-assisted emulsification microextraction based on applying low density organic solvent followed by gas chromatography-flame ionization detection has been developed for the simultaneous determination of permethrin and deltamethrin in spinach samples. Parameters affecting the extraction process have been optimized. Under the optimum conditions, the calibration plots were linear in the range of 0.01–20 mg/kg with the determination coefficient (r2) higher than 0.990. The limits of detection were 0.007 and 0.006 mg/kg for deltamethrin and permethrin, respectively, which are lower than the maximum residue levels established by various official organizations. The proposed procedure has high potential for the use as a sensitive method for the determination of deltamethrin and permethrin residues in spinach samples. [ABSTRACT FROM AUTHOR]

NMR relaxation times of the dual-specific nuclei of metal cobalt-59 and ligand methine carbon-13 for tris(2,4-pentanedionato)cobalt(III), which is commonly named as tris(acetylacetonato)cobalt(III), [Co(acac)3], in four organic solvents, acetonitrile, dichloromethane, chloroform, and benzene, have been measured at several temperatures. The rotational correlation times of complex molecules in different solvents, obtained from the NMR relaxation times, can be semi-quantitatively described by the hydrodynamic Debye–Einstein–Stokes (DES) model. However, the slight deviations from the DES model were observed dependent on the kind of solvents, where the effective rotational volume increased in the order of C6H6 ~ CH3CN < CH2Cl2 < CDCl3. In chloroform solution, where two solvent molecules are specifically bound to [Co(acac)3] in the ligands' hollows, the complex molecule can rotate accompanying the chloroform molecules solvated and/or the friction in the outer coordination sphere can be increased by the specific interactions in view of the larger effective rotational volume. The present results indicate that the rotational dynamics of [Co(acac)3] in solution is quite sensitive to the solute–solvent interactions in the outer coordination sphere as well as the viscosity of solution. [ABSTRACT FROM AUTHOR]

A new type of hexafluorobutanol (HFB) primary alcohol ethoxylate (AEO)-based supramolecular solvent (SUPRAS) with density higher than water was prepared for the first time. HFB acted as AEO micelle-forming agent and density-regulating agent for SUPRAS formation. The prepared SUPARS was applied as extraction solvent for vortex-assisted direct microextraction of malachite green (MG) and crystal violet (CV) from lake sediment followed by high-performance liquid chromatographic determination. In the present work, SUPRASs prepared from AEO with different carbon chains as the amphiphiles and various coacervation agents were investigated. SUPARS formed from MOA-3 and HFB provided better extraction efficiency in comparison with other SUPRASs. Parameters influencing the extraction recovery of target analytes including the type and volume of AEO, volume of HFB, and vortex time were investigated and optimized. Under optimized conditions, linearity in the range of 2.0–400 μg g−1 for MG and 2.0–500 μg g−1 for CV with a correlation coefficient higher than 0.9947 was obtained. Limits of detection of 0.5 μg g−1 and relative standard deviations in the range of 0.9–5.8% were obtained. Compared to conventional extraction techniques for analysis of analytes in solid samples, the proposed method reduced sample usage and eliminated a primary extraction process by using a toxic organic solvent. The proposed method is simple, fast, and green and can be used for the analysis of target analytes in solid samples. [ABSTRACT FROM AUTHOR]

Dispersion of colloidal particles in water or oil is extensively desired for industrial and environmental applications. However, it often strongly depends on indispensable assistance of chemical surfactants or introduction of nanoprotrusions onto the particle surface. Here we demonstrate the omnidispersity of hydrophilic-hydrophobic heterostructure particles (HL-HBPs), synthesized by a surface heterogeneous nanostructuring strategy. Photo-induced force microscopy (PiFM) and adhesion force images both indicate the heterogeneous distribution of hydrophilic domains and hydrophobic domains on the particle surface. These alternating domains allow HL-HBPs to be dispersed in various solvents with different polarity and boiling point. The HL-HBPs can efficiently adsorb organic dyes from water and release them into organic solvents within several seconds. The surface heterogeneous nanostructuring strategy provides an unconventional approach to achieve omnidispersion of colloidal particles beyond surface modification, and the omnidispersible HL-HBPs demonstrate superior capability for dye recycle merely by solvent exchange. These omnidispersible HL-HBPs show great potentials in industrial process and environmental protection. Dispersion of colloidal particles in water or oil is desired for industrial and environmental applications but it often strongly depends on indispensable assistance of chemical surfactants or introduction of nanoprotrusions onto the particle surface. Here, the authors demonstrate the omnidispersity of hydrophilic-hydrophobic heterostructure particles, synthesized by a surface heterogeneous nanostructuring strategy. [ABSTRACT FROM AUTHOR]

Carotenoids have a wide range of applications in the food, pharmaceutical, and cosmetic industries as natural coloring agents and antioxidants. Consequently, industries are more concerned about extracting them from natural resources and by-products. The present research aimed to evaluate the extraction efficiency of carotenoids from orange peels using hydrophobic deep eutectic solvents (HDESs) as alternatives for organic solvents. The antioxidant capacity and color stability of HDESs extracts were monitored for 20 days and to intensify the extraction process, ultrasound-assisted extraction (UAE) was optimized using a response surface methodology (RSM). Menthol:Eucalyptol (Me:Eu) extract showed the highest carotenoid extraction yield [359.3 ± 3.5 mg/100 g of fresh weight (fw)], and also presented high stability during the storage period. HDESs extracts showed higher antioxidant capacity compared to hexane extracts, while Me:Eu extracts showed the lowest color variation (5.9 ± 0.2). Optimal parameters using Me:Eu were extraction time of 20 min, ultrasonic power of 120 W (60%), and solid–liquid ratio of 1:20 (g/mL) reaching a carotenoid content of 573.4 mg/100 gfw. While, C12:C8 optimal parameters were 10 min, 80 W (40%), and a solid–liquid ratio of 1:10 (g/mL), providing a carotenoid content of 183.7 mg/100 gfw. To establish if the solvents used are greener alternatives, the EcoScale was used and showed that UAE is a sustainable method to recover carotenoids using HDESs. Overall, the results showed that HDESs can improve carotenoid stability, and when combined with the intrinsic safety and edibility of their components, it makes these extracts appealing for food industry. [ABSTRACT FROM AUTHOR]

Highlights: High Coulombic efficiency of over 99% for dendrite-free K||Cu cell after 820 cycles. Year-scale-cycling performance of organic PTCDI cathode over 2,100 cycles. Flexible device demonstration such as fibre cell still could operate when cut into three fibre cells. High degrees of freedom (DOF) for K+ movement in the electrolytes is desirable, because the resulting high ionic conductivity helps improve potassium-ion batteries, yet requiring support from highly free and flammable organic solvent molecules, seriously affecting battery safety. Here, we develop a K+ flux rectifier to trim K ion's DOF to 1 and improve electrochemical properties. Although the ionic conductivity is compromised in the K+ flux rectifier, the overall electrochemical performance of PIBs was improved. An oxidation stability improvement from 4.0 to 5.9 V was realized, and the formation of dendrites and the dissolution of organic cathodes were inhibited. Consequently, the K||K cells continuously cycled over 3,700 h; K||Cu cells operated stably over 800 cycles with the Coulombic efficiency exceeding 99%; and K||graphite cells exhibited high-capacity retention over 74.7% after 1,500 cycles. Moreover, the 3,4,9,10-perylenetetracarboxylic diimide organic cathodes operated for more than 2,100 cycles and reached year-scale-cycling time. We fabricated a 2.18 Ah pouch cell with no significant capacity fading observed after 100 cycles. [ABSTRACT FROM AUTHOR]

Guidelines identifying appropriate DNA extraction methods for both museum and modern biological samples are scarce or non-existent for mammalian species. Yet, obtaining large-scale genetic material collections are vital for conservation and management purposes. In this study, we evaluated five protocols making use of either spin-column, organic solvents, or magnetic bead-based methods for DNA extraction on skin samples from both modern, traffic-killed (n = 10) and museum (n = 10) samples of European hedgehogs, Ericaneus europaeus. We showed that phenol–chloroform or silica column (NucleoSpin Tissue) protocols yielded the highest amount of DNA with satisfactory purity compared with magnetic bead-based protocols, especially for museum samples. Furthermore, extractions using the silica column protocol appeared to produce longer DNA fragments on average than the other methods tested. Our investigation demonstrates that both commercial extraction kits and phenol–chloroform protocol retrieve acceptable DNA concentrations for downstream processes, from degraded remnants of traffic-killed and museum samples of mammalian specimens. Although all the tested methods could be applied depending on the research questions and laboratory conditions, commercial extraction kits may be preferred due to their effectiveness, safety and the higher quality of the DNA extractions. [ABSTRACT FROM AUTHOR]

In a new attempt to separate some sulbactam combinations by green chemical method we came up with this research in which an ecofriendly, green, sustainable and selective method was established for separation of four antibiotics, namely, cefoperazone (CFP), cefixime (CFX), ampicillin (AMP) and sulbactam (SLB). No organic solvents were used in the composition of the mobile phase as it was replaced by mixing two surfactants together, sodium dodecyl sulfate (SDS) and polyoxyethylene-23-lauryl ether (Brij-35). Effect of varying the concentrations of the two surfactants on chromatographic separation was studied. Optimum separation was maintained using a mobile phase consisting of 0.01 mol/L SDS, 0.03 mol/L Brij-35, 0.4% Tri-ethylamine (TEA) and pH of 2.8 adjusted by using 1 M ortho-phosphoric acid on reversed phase Isère C18 BDS column with temperature of 40 °C at flow rate 1 mL/min, wavelength 215 nm, and the total run time was 6 min. Validation of the proposed method has been made according International Conference of Harmonization (ICH) guidelines at linearity range of 10–200 µg mL−1 for all drugs under study, high accuracy results (recovery range 98.39–100.35%). and the variation coefficient (RSD) of the points on the calibration curve was ranged from (0.1–1.7%) indicating precise method. The LOQ was (6.09 μg mL−1) for CFP, (6.07 μg mL−1) for CFX, (3.85 μg mL−1) for AMP and (7.20 μg mL−1) for SLB. Successful applications were made on marketed dosage forms with recovery range of (100.16–102.25%) and RSD of (0.03–1.88%). The method was verified on the Green Analytical Procedure Index (GAPI) and Analytical Greenness metric approach (AGREE) and it was found to be an excellent green alternative method. [ABSTRACT FROM AUTHOR]

Given the huge significance of organic solvents in several industrial processes, the use of membranes for recovering the solvents has evolved into an industrially viable process. The current work has been focused on studying the effect of minor changes in the chemistry of the reacting monomers on the organic solvent nanofiltration/solvent resistance nanofiltration (OSN/SRNF) performance of the membranes. The two aliphatic amines with varying aliphatic chain lengths between primary and secondary amines were selected for this purpose. Based on the structure of the resultant active layer, the Janus nanofiltration performance of the membrane was evaluated. The two membranes, 4A-TPC@crosslinked PAN and 4A-3P@crosslinked PAN were fabricated by using two different tetra-amines, 4A (N,N′-bis(3-aminopropyl)ethylenediamine) and 4A-3P (N,N′-Bis(2-aminoethyl)-1,3-propanediamine) crosslinked with terephthaloyl chloride (TPC) on a crosslinked polyacryonitrile (PAN) support through interfacial polymerization (IP). The presence of multiple hydrophobic –CH2– groups in the structures of the aliphatic amines 4A and 4A-3P develops hydrophobic sites in the hydrophilic polyamide active layers of the membranes. In addition, 4A has two secondary amino groups separated by ethylene (–CH2–CH2–) groups, whereas in 4A-3P, the two secondary amino groups are separated by propylene (–CH2–CH2–CH2–) leading to variation in the structural features and performance of the two membranes. Both membranes were fully characterized by several membrane characterization techniques and applied for OSN/SRNF using both polar (methanol, ethanol, and isopropanol) and non-polar (n-hexane and toluene) solvents. Different dyes (Congo red, Eriochrome black T, and Methylene blue) were used as model solutes during the filtration experiment. The 4A-3P-TPC@crosslinked PAN showed n-hexane and toluene flux of 109.9 LMH and 95.5 LMH, respectively. The Congo red (CR) showed the highest rejection, reaching 99.1% for the 4A-TPC@Crosslinked PAN membrane and 98.8% for the 4A-3P-TPC@Crosslinked PAN membrane. [ABSTRACT FROM AUTHOR]

The eggs laid by the orb web spider Trichonephila clavata must overwinter in bitterly freezing and dry conditions before hatching, but there does not seem to be any protection like a compact silk case covering the entire eggmass. Instead, the surface of the eggmass is completely coated with a milky coating called chorionic microspheres (CM). Therefore, we investigated the fine structural characteristics of CM to demonstrate their ecological importance. Although the diameter of CM in outer eggmass exhibits a significant variation, the chorionic surface is coated with a single layer of CM, characterized by a consistent diameter of approximately 2.3 µm. The surface structure of aggregated CM shows short papillary projections demonstrating segmental adhesion of mucous components. CM is insoluble in water but partially soluble in anhydrous ethanol, and its spherical structure is completely decomposed by hexafluoroisopropanol (HFIP), a strong organic solvent. Since our fine structural observations clearly show that CM is not derived from vitellogenic or choriogenetic processes, the CM adhesive coatings during ovipositional process appears to be equivalent to cocoon silk for various protective functions in silken eggcase. [ABSTRACT FROM AUTHOR]

A method of dispersive liquid–liquid microextraction, based on the dispersion of an extractant by the gas phase formed as a result of a phase transition, i.e., the evaporation of a highly volatile nonpolar organic solvent (dispersant) upon heating the extraction,—is developed. The analytical capabilities of the method are shown in the determination of preservatives (sorbic and benzoic acids) in soft drinks for baby food by high-performance liquid chromatography with photometric detection. The extractant and the dispersant for the microextraction of preservatives are chosen a terpenoid and a highly volatile organochlorine solvent, respectively, which excluded the use of polar organic solvents for dispersing phases, with which the distribution coefficients are reduced. The limits of detection (3σ) for sorbic and benzoic acids are 0.3 mg/L. The developed method does not require centrifugation for phase separation. [ABSTRACT FROM AUTHOR]

Rational integration of native enzymes and nanoscaffold is an efficient means to access robust biocatalyst, yet remains on-going challenges due to the trade-off between fragile enzymes and harsh assembling conditions. Here, we report a supramolecular strategy enabling the in situ fusion of fragile enzymes into a robust porous crystal. A c2-symmetric pyrene tecton with four formic acid arms is utilized as the building block to engineer this hybrid biocatalyst. The decorated formic acid arms afford the pyrene tectons high dispersibility in minute amount of organic solvent, and permit the hydrogen-bonded linkage of discrete pyrene tectons to an extended supramolecular network around an enzyme in almost organic solvent-free aqueous solution. This hybrid biocatalyst is covered by long-range ordered pore channels, which can serve as the gating to sieve the catalytic substrate and thus enhance the biocatalytic selectivity. Given the structural integration, a supramolecular biocatalyst-based electrochemical immunosensor is developed, enabling the pg/mL detection of cancer biomarker. Integration of nanomaterials and enzymes has potential in the development of robust biocatalysts, but preparation can still be technically challenging. Here, the authors report the preparation of a hydrogen-bonded organic framework biocatalyst and its use as an immunosensor. [ABSTRACT FROM AUTHOR]

The potentiometric titration (PT) method has been applied for the first time to investigate the stability of l-ascorbic acid (H2Asc) and to determine its degradation products in aqueous solutions. The presented electrochemical procedures can be considered to be a fast, simple and inexpensive way to control the stability of H2Asc in a regular analytical practice as well as in the chemical and pharmaceutical industries. Experimental data as well as modeling suggest that the enolic form of 2,3-diketogulonic acid predominates in a solution as the main product of dehydroascorbate degradation. Furthermore, the PT results supported by conductometric measurements and electrospray ionization mass spectrometry data enable us to propose the putative mechanism of the H2Asc decomposition. Moreover, it has been proven that among different types of investigated electrolytes (KNO3, KClO4 and KSCN), the thiocyanate ions (SCN−) reveal the stabilizing effect against the degradation of H2Asc. Thus, the presence of SCN− in the H2Asc solution is proposed as an alternative way for some organic solvents earlier used. Finally, a new paraffin-protection-layer procedure has been recommended for studying as well as storage of the solutions comprising components sensitive to external factors (e.g. O2, CO2) and to evaporation. [ABSTRACT FROM AUTHOR]

Design readily available and inexpensive aerogels as potential sorbent materials for oil–water separation is extremely significant because of the increasing discharge of domestic oil pollution. Hereby, a novel superhydrophobic indole-based hemiaminal aerogel (PCINA) without any post-surface treatment was fabricated by a facile, simple and mild method via sol–gel technology followed by freeze-drying. The as-obtained indole-based hemiaminal aerogel exhibited high absorption capacity for varieties of oils and organic solvents. In addition, the separation efficiency of oil–water mixture was as high as 99.8%, even the separation efficiency of emulsion could achieve to 98.2%. More excitingly, the indole-based hemiaminal aerogel PCINA possessed repeatability and regeneration due to the feasible desorption and rapid degradation, suggesting that the green and renewable aerogel was a promising material for the treatment of oil contaminants in different fields. [ABSTRACT FROM AUTHOR]

Grape juices and wines are rich in numerous groups of polyphenolic compounds which require a dedicated separation technique for such complex samples. LC × LC is considered the best technique for the analysis of such samples as it can achieve better resolution and higher peak capacity compared to 1D LC. The ever-growing demand for protecting the environment necessitates reducing or eliminating hazardous solvents to improve the environmental friendliness of analytical procedures. In this study, propylene carbonate was used as an eco-friendly mobile phase component in comprehensive two-dimensional liquid chromatography to analyze phenolic compounds in grape juices and a dealcoholized wine sample. Novel green RPLC × RPLC–DAD and RPLC × RPLC–MS methods were developed for the first time to identify phenolic compounds in five samples (two red grape juice samples, two white grape juice samples, and one dealcoholized wine sample). Four different RPLC × RPLC systems were developed; three systems were connected to a diode array detector (RPLC × RPLC–DAD), while the fourth system was connected to DAD and MS detectors (RPLC × RPLC–DAD–ESI–MS). Solvent X (propylene carbonate:ethanol, 60:40) was adopted as a green organic modifier in the first dimension (1D) and methanol in the second dimension (2D). The practical peak capacity and the surface coverage were calculated as metrics to measure the separation performance of all proposed systems. The orthogonality values for the setups ranged from 0.64 to 0.92 when calculated by the convex hull method, and from 0.54 to 0.80 when calculated by the asterisk equations method. The practical peak capacity production rate ranged from 14.58 to 22.52 peaks/min. The results revealed that the phenolic compounds were separated efficiently with good coverage of the 2D separation space and high peak capacity. A total of 70 phenolic compounds were detected based on MS data and information from the literature. [ABSTRACT FROM AUTHOR]

Lamellar graphene oxide (GO) membranes have gained substantial interest for molecular separation processes. However, GO membranes have shown inefficient separation performance levels due to their possession of sufficient functional groups that lead to swelling under applied hydraulic pressure. Herein, we demonstrate a highly stable and ultrafast filtrable graphene oxide-boron nitride (GOBN) hybrid membrane by incorporating boron nitride (BN) nanosheets into a GO membrane to restrict swelling and provide efficient hydraulic pressure separation characteristics. This new heterostructure retains the GOBN membrane microstructure and provides more nanochannels around the incorporation sites due to the small size of BN nanosheets; this phenomenon increases the permeance to 1310 Lm−2h−1bar−1, which is nearly six times higher than that of the pure GO membrane, with a high rejection reaching 99.2% for aqueous organic dyes. More importantly, the GOBN hybrid membrane shows an impressive permeance and dye molecule rejection performance characteristic across a range of organic solvents, such as methanol, ethanol, and isopropyl alcohol; the performance characteristics are better than those for the GO membrane. Our GOBN membrane with a stable microstructure opens opportunities for developing a high-performance multiple solvent nanofiltration membrane that surpasses the permeability-selectivity trade-off. [ABSTRACT FROM AUTHOR]

In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. "Classroom" is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. One of the common physical chemistry experiments carried out in undergraduate programs is the determination of the partition coefficient (KD) in which a solute is distributed between organic and aqueous layers. After the experiment, the used-up organic layer and stock organic layer are discarded without proper measure, which poses a serious threat to our environment. In this article, we propose a simple, cost-effective and environment-friendly method to recycle the organic solvent used during the experiment. [ABSTRACT FROM AUTHOR]

Aromatic amines (AA) are carcinogenic compounds that can enter the human body through many sources, one of the most important being tobacco smoke. They are excreted with the urine, from which they can be extracted and measured. To that end, hollow fiber-liquid-phase microextraction (HF-LPME) and parallel artificial liquid membrane extraction (PALME) were optimized for the analysis of representative aromatic amines, as alternatives to liquid–liquid extraction (LLE). Relevant extraction parameters, namely organic solvent, extraction time, agitation speed, and acceptor solution pH, were studied, and the two optimized techniques—HF-LPME: dihexyl ether, 45 min, 250 rpm, and pH 1; PALME: undecane, 20 min, 250 rpm and pH 1—were compared. Comparison of the optimized methods showed that significantly higher recoveries could be obtained with PALME than with HF-LPME. Therefore, PALME was further validated. The results were successful for nine different AA, with regression coefficients (R2) of at least 0.991, limits of detection (LOD) of 45–75 ng/L, and repeatability and peak area relative standard deviations (RSD) below 20%. Furthermore, two urine samples from smokers were measured as proof of concept, and 2-methylaniline was successfully quantified in one of them. These results show that PALME is a great green alternative to LLE. Not only does it use much smaller volumes of toxic organic solvents, and sample—enabling the study of samples with limited available volumes—but it is also less time consuming and labor intensive, and it can be automated. [ABSTRACT FROM AUTHOR]

RuO2 electrodes are spray-deposited with various precursor solution concentrations using aqueous/organic solvent mixtures. RuO2 has a preferential growth along the (110) plane of the rutile tetragonal crystal structure with porous morphology. The bandgap decreases from 2.05 to 1.77 eV with increasing precursor solution concentrations. Electrical resistivity of 0.12 × 104 Ωcm has been observed for RuO2 films prepared with a 50 mM precursor solution concentration. RuO2 film showed a specific capacitance of 893 Fg−1 at a scan rate of 5 mVs−1 and 964 Fg−1 at 0.5 Ag−1 with 93.67% capacitance retention over 1000 cycles. As a RuO2 electrode supercapacitor device, the energy density reaches 76.56 Whkg−1 at a power density of 1701 Wkg−1. The solution resistance is about 0.32 Ω for the RuO2 electrode prepared with a precursor solution concentration of 50 mM. The use of an aqueous/organic mixture as solvent improves the electrochemical supercapacitive performance of RuO2 electrodes. [ABSTRACT FROM AUTHOR]

Organic solvents have been commonly used in the printing process for a long time in gravure printing applications. Using organic solvents in solvent-based ink is responsible for fire hazards, volatile organic compounds emission, and increasing extra printing costs. The current study aimed to replace solvent-based ink with water-based ink to reduce volatile organic compound emissions and carbon footprints in gravure printing without affecting overall printing quality in order to fill a research gap because none of the studies were reported as best of all authors' knowledge. The polyethylene terephthalate film was printed by laser engraved cylinder having reduced engraving cell depth compared to electronically engraved printing cylinders which result in less consumption of printing ink, hence reducing the raw materials consumption. The cost of printing one kg of polyethylene terephthalate film with water-based ink was reduced by 1.85US$, and volatile organic compounds emissions were reduced from 3373 ppm to 2478 ppm compared to solvent-based ink. The use of water-based ink also reduced the carbon footprint by 3.04 kg. The current study shows that strict implementation of water-based ink has a high potential for saving the cost and reducing the emission of volatile organic compounds, which are very dangerous to the ambient environment, humans, and society. This study's outcome will help prepare the benchmark for green manufacturing systems in gravure printing applications to improve the environment and humanity. [ABSTRACT FROM AUTHOR]

A sunlight-induced tandem air oxidation-condensation of alcohols with ortho-substituted anilines or malononitrile for the efficient synthesis of benz-imidazoles/-oxazoles/-thiazoles, or benzylidene malononitrile catalyzed by Co-isatin-Schiff-base-MIL-101(Fe) as a heterogeneous multifunctional bio-photocatalyst is reported. In these reactions, Co-isatin-Schiff-base-MIL-101(Fe) acts both as a photocatalyst, and a Lewis acid to catalyze the reaction of the in-situ formed aldehydes with o-substituted anilines or malononitrile. A significant decrease in the band gap energy and an increase in the characteristic emission of MIL-101(Fe) after functionalization with cobalt Schiff-base according to the DRS analysis and fluorescence spectrophotometry, respectively, indicate that the photocatalytic effectiveness of the catalyst is associated primarily to the synergetic influence of Fe–O cluster and Co-Schiff-base. EPR results obviously pointed out that Co-isatin-Schiff-base-MIL-101(Fe) is capable of creating 1O2 and O2⋅− as active oxygen species under visible light irradiation. Using an inexpensive catalyst, sunlight irradiation, air as a cost-effective and abundant oxidant, and a low amount of the catalyst with recoverability and durability in ethanol as a green solvent, make this methodology as an environmentally friendly process with energy-saving organic synthetic strategies. Furthermore, Co-isatin-Schiff-base-MIL-101(Fe) displays excellent photocatalytic antibacterial activity under sunlight irradiation against E. coli, S. aureus and S. pyogenes. Based on our knowledge, this is the first report of using a bio-photocatalyst for the synthesis of the target molecules. [ABSTRACT FROM AUTHOR]

The aim of this study is to correlate the solubility and electrospinnability of gelatin in different organic solvent systems. Teas graph was employed using the Hansen parameters in this systematic study to map the solvents that dissolve and enable the electrospinning of gelatin. It was found that in some cases, the solvent dissolved gelatin but the solution was not spinnable. Increasing the hydrogen bonding force (fh) assisted in the electrospinning of the gelatin solution. Higher dispersion force (fd) improves the electrospinnability at lower concentration of gelatin. The viscosity of the solution of pure acetic acid (AA) is higher than the binary solution of 3:1 AA/water and 3:1 AA/tetrahydrofuran (THF) for the same concentration of gelatin; the higher viscosity enhanced the electrospinning properties. Interestingly, field-emission scanning electron microscopy arrayed that the effect of increasing the concentration of gelatin in the pure AA system resulted in the formation of thicker fibres, however, it induced the formation of uniform fibres in the 3:1 AA/water system, whereas beaded morphology was obtained when lower concentration of gelatin was used. The fibres obtained from electrospinning the solution of 3:1 AA/THF resulted in the formation of thicker and non-uniform fibres due to the low electrical conductivity as well as the high volatility of the solution. Attenuated total reflectance-Fourier transform infrared spectroscopy portrayed all the major peaks of gelatin in the electrospun fibres. However, widening of the Amide-A peak of gelatin was observed when the solvent system of formic acid and 3:1 AA/THF were used. Thermal study of the fibre mats depicts that the binary solvent system using AA is more suitable to obtain nanofibres with more analogous structure to pristine gelatin. The electrospun samples of gelatin in the different solvent systems did not exhibit any cytotoxity on the HeLa cell line. Teas graph can be used as a quick solvent selection tool to prepare electrospinning solutions of gelatin blended with synthetic polymers to obtain nanofibres for biomedical applications. [ABSTRACT FROM AUTHOR]

Layered two-dimensional materials can potentially be utilized for organic solvent nanofiltration (OSN) membrane fabrication owing to their precise molecular sieving by the interlayer structure and excellent stability in harsh conditions. Nevertheless, the extensive tortuosity of nanochannels and bulky solvent molecules impede rapid permeability. Herein, nanoporous graphene (NG) with a high density of sp2 carbon domain was synthesized via sequential thermal pore activation of graphene oxide (GO) and microwave-assisted reduction. Due to the smooth sp2 carbon domain surfaces and dense nanopores, the microwave-treated nanoporous graphene membrane exhibited ultrafast organic solvent permeance (e.g., IPA: 2278 LMH/bar) with excellent stability under practical cross-flow conditions. Furthermore, the membrane molecular weight cut-off (MWCO) is switchable from 500 Da size of molecule to sub-nanometer-size molecules depending on the solvent type, and this switching occurs spontaneously with solvent change. These properties indicate feasibility of multiple (both binary and ternary) organic mixture separation using a single membrane. The nanochannel structure effect on solvent transport is also investigated using computation calculations. Layered 2D materials can be used for organic solvent nanofiltration (OSN) membrane fabrication due to precise molecular sieving by the interlayer structure and stability in harsh conditions. Here authors synthesise sp2-enriched nanoporous graphene by microwave treatment and demonstrate its excellent OSN performance. [ABSTRACT FROM AUTHOR]

Terpene cyclases catalyze one of the most powerful transformations with respect to efficiency and selectivity in natural product (bio)synthesis. In such polyene cyclizations, structurally highly complex carbon scaffolds are built by the controlled ring closure of linear polyenes. Thereby, multiple C,C bonds and stereocenters are simultaneously created with high precision. Structural pre-organization of the substrate carbon chain inside the active center of the enzyme is responsible for the product- and stereoselectivity of this cyclization. Here, we show that in-situ formed fluorinated-alcohol-amine supramolecular clusters serve as artificial cyclases by triggering enzyme-like reactivity and selectivity by controlling substrate conformation in solution. Because of the dynamic nature of these supramolecular assemblies, a broad range of terpenes can be produced diastereoselectively. Mechanistic studies reveal a finely balanced interplay of fluorinated solvent, catalyst, and substrate as key to establishing nature's concept of a shape-selective polyene cyclization in organic synthesis. Terpene cyclases enable the synthesis of (poly)cyclic carbon frameworks via ring closure of linear polyenes. Here, the authors report in-situ formed fluorinated-alcohol-amine supramolecular clusters that mimic terpene cyclases for shape-controlled polyene cyclizations. [ABSTRACT FROM AUTHOR]

A procedure is proposed for the extraction of 2,6-diisobornyl-4-methylphenol (IBP), the molecule with potential multi-target activity, and its active metabolite 2,6-diisobornyl-4-hydroxymethylphenol (IBP–OH) from human and rat plasma samples for further determination by liquid chromatography–tandem mass spectrometry. The solubility of IBP (in mg/mL) in various organic solvents is determined. In particular, the compound is readily soluble in chloroform (346 ± 14), methyl tert-butyl ether (98.6 ± 3.8), and ethyl acetate (96.8 ± 2.0). It is shown that the use of a mixture of chloroform and isopropanol (5 : 1, v/v) as an extraction system with simultaneous protein precipitation makes it possible to extract only 66 ± 10% of IBP, while the recovery of IBP–OH is 96 ± 7%. Pre-dilution of 200 µL of plasma with 300 µL saline increases IBP recovery to 100 ± 4%. Drying the extracts in a vacuum concentrator (air, 45°C) with the further reconstitution of the residues in 300 μL of acetonitrile facilitates the purification of biosamples and the preconcentration of analytes. The total sample preparation time does not exceed 70 min, and the duration of an analysis is 7 min, the injection volume is 2 µL. The procedure has been successfully tested on actual rat plasma samples after a single oral administration of IBP (10 mg/kg in oil) in the framework of pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

We report the electronic absorption spectroscopy of 7,7,8,8-tetracyanoquinodimethane (TCNQ) and its fluorinated derivatives (F2TCNQ and F4TCNQ), well-known electron-accepting molecules in common organic solvents (toluene, chlorobenzene, acetonitrile, and ethanol) under controlled exposure to air (O2) and UV light. All compounds (FxTCNQ (x = 0, 2, 4)) were stable in a neutral state (FxTCNQ0) in toluene and chlorobenzene, even under both O2 and UV light. On the other hand, in EtOH, the formation of FxTCNQ·− was monitored upon controlled exposure to O2 or UV light. Especially in air-equilibrated ethanol upon the UV-illumination, efficient α,α-dicyano-p-toluoylcyanide anion (DCTC−) and its fluorinated derivatives were generated evinced by the absorption peak near 480 nm, whereas the reaction was shut off by removing O2 or blocking UV light, thereby keeping FxTCNQ·− stable. However, even in deaerated ethanol, upon the UV-illumination, the anion formation of TCNQ and its fluorinated derivatives (FxTCNQ·−, x = 0, 2, 4) was inevitable, showing the stability of FxTCNQ0 depends on the choice of solvent. [ABSTRACT FROM AUTHOR]