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Malaria is an endemic disease in tropical countries, including Indonesia, with a high annual mortality rate. Because of that, serious attention shall be given to find new antimalarial agents that are highly active for medical treatment. In this work, we designed and synthesized three calix[4]resorcinarene derivatives and evaluated them as antimalarial agents through in vitro heme polymerization inhibitory assay. The calix[4]resorcinarenes were prepared from resorcinol and corresponding aldehyde derivatives in ethanol media through a cyclo-condensation reaction. The calix[4]resorcinarene products were obtained in 31.1–85.1% yield. The synthesized compounds were subjected to structure elucidation using spectroscopy techniques. The antimalarial activity of calix[4]resorcinarene with aromatic substituent (IC50 = 0.198 mg/mL) was higher than the aliphatic ones (IC50 = 0.282–0.814 mg/mL). It was found that all calix[4]resorcinarenes in this work exhibited stronger antimalarial activity than chloroquine diphosphate as the positive control (IC50 = 1.157 mg/mL). The calix[4]resorcinarenes could interact with hydrogen bonding, thus inhibiting the heme polymerization process. These findings demonstrate that calix[4]resorcinarene derivatives are potential antimalarial agents to be developed for effective medical treatment in the near future.

An efficient continuous‐flow (CF) protocol was designed for the hydrogenation of lignin‐derived aromatics to the corresponding cycloalkanes derivatives. A parametric analysis of the reaction was carried out by tuning the temperature, the H2 pressure and the flow rate, and using diphenyl ether (DPE) as a model substrate, commercial Ru/C as a catalyst, and isopropanol as a solvent: at 25 °C, 50 bar H2, and a flow rate of 0.1 mL min−1, dicyclohexyl ether was achieved in an 86 % selectivity, at quantitative conversion. By‐products from the competitive C−O bond cleavage of DPE, cyclohexanol and cyclohexane, did not exceed 14 % in total. Remarkably, prolonged experiments demonstrated an excellent stability of the catalyst whose performance was unaltered for up to 420 min of time‐of‐stream. A substrate scope evaluation proved that under the same conditions used for DPE, a variety of substrates including alkoxy‐, allyl‐, and carbonyl‐functionalized phenols, biphenyl, aryl benzyl‐ and phenethyl ethers (10 examples) yielded the ring‐hydrogenated products with selectivity up to 99 % at complete conversion. [ABSTRACT FROM AUTHOR]

BackgroundNMDA receptor modulation by hydrocarbons is associated with a molar water solubility cut-off. Low-affinity phenolic modulation of GABAA receptors is also associated with a cut-off, but at much lower molar solubility values. We hypothesized that other anesthetic-sensitive ion channels exhibit distinct cut-off effects associated with hydrocarbon molar water solubility, and that cut-off values are comparatively similar between related receptors than phylogenetically distant ones.MethodsGlycine or GABAA receptors or TREK-1, TRESK, Nav1.2, or Nav1.4 channels were expressed separately in frog oocytes. Two electrode voltage clamp techniques were used to study current responses in the presence and absence of hydrocarbon series from eight functional groups with progressively increasing size at saturated aqueous concentrations. Null response (cut-off) was defined by current measurements that were statistically indistinguishable between baseline and hydrocarbon exposure.ResultsIon channels exhibited cut-off effects associated with hydrocarbon molar water solubility in the following order of decreasing solubility: Nav1.2 ≈ Nav1.4 ≳ TRESK ≈ TREK-1 > GABAA >> glycine. Previously measured solubility cut-off values for NMDA receptors were intermediate between those for Nav1.4 and TRESK.ConclusionsWater solubility cut-off responses were present for all anesthetic-sensitive ion channels; distinct cut-off effects may exist for all cell surface receptors that are sensitive to volatile anesthetics. Suggested is the presence of amphipathic receptor sites normally occupied by water molecules that have dissociation constants inversely related to the cut-off solubility value. Poorly soluble hydrocarbons unable to reach concentrations sufficient to out-compete water for binding site access fail to modulate the receptor.

The hydrophobic force is one of the most dominant factors in protein folding. A protein becomes functional only when it achieves its three-dimensional structure and stability upon folding. For a better understanding of the hydrophobic effects and their function in protein folding, quantitative measurement of the hydrophobicity of amino acid side chains is crucial. Spike protein is the primary structural protein in SARS-CoV-2 and SARS-CoV. This study explores how protein sequences in SARS-CoV-2 and SARS-CoV spike proteins encode hydrophobic interactions. Computational tools/techniques have been utilized to investigate the protein sequences of the spike proteins of SARS-CoV-2 and SARS-CoV. Investigations provided an estimate of hydrophobic distribution and its relative strength, indicating a hydrophobic pattern. Analysis of the spike protein's hydrophobic profile may help identify and treat the virus-caused disease; additionally, it can give an insight into the transmissibility and pathogenicity of the virus. [ABSTRACT FROM AUTHOR]

Procedures for preparing 4,4-dimethyloxazoline (DMOX) and pyrrolidine derivatives from fatty acid methyl esters (FAMEs) were modified to provide milder and simpler conditions for the derivatization reactions widely used in the mass spectrometric analysis of fatty acids. DMOX and pyrrolidine derivatives were obtained overnight at room temperature in the presence of sodium borohydride. The proposed method, involving a low-temperature condensation-cyclization of FAME to DMOX, allows for the direct preparation of DMOX derivatives from non-hydroxy, 2- and 3-hydroxy acid methyl esters. The described simple one-pot procedures are "mild" alternatives to existing methods, which require the use of elevated temperatures. [ABSTRACT FROM AUTHOR]

Using GC-MS the composition of hydrocarbons in maltenes from heavy naphthenic crude oil (Usinskoye oilfield) after cracking in the presence of WC/Ni–Cr additive and without it has been studied. Cracking of maltenes was carried out at 450°С for 2 hours in isothermal mode. Using WC/Ni–Cr additive during cracking contributes to the deepening of the degradation reactions in hydrocarbons and resins. It is shown that the amount of low molecular weight C11–C19 alkanes and C9–C10 alkylbenzenes increases significantly in cracking products when using WC/Ni–Cr, the content of cyclohexanes and bicyclanes decreases, complete destruction of tri-, tetra- and pentacyclic saturated hydrocarbons occurs compared to cracking without the additive. There are changes in the composition of naphthenic hydrocarbons. Along with degradation reactions, condensation reactions occur, leading to the formation of polycyclic aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

• Aromatic bismaleimides and aliphatic bismaleimides were prepared. • Aliphatic bismaleimides have lower activation energy. • Aromatic bismaleimides possess superior thermal stability and lower dielectric loss. • Aliphatic bismaleimides exhibit lower dielectric constant and low water absorption. In this paper, three aromatic bismaleimides (BMI-70, BMI-DE and BMI-80) and two aliphatic bismaleimides (BMI-DDA and BMI-C36) were synthesized. The structures were characterized using nuclear magnetic resonance (NMR) spectra and Fourier transform infrared (FT-IR) spectra. Their polymerization behaviors were discussed by non-isothermal differential scanning calorimetry (DSC). The thermal and dielectric properties of the poly(bismaleimide) were investigated using thermogravimetric analysis (TGA), dynamic thermo-mechanical analysis (DMA), and an impedance analyzer. The results indicate that the aliphatic bismaleimides exhibit lower apparent activation energies and dielectric properties, with BMI-DDA displaying an average activation energy of 105.5 kJ mol−1 and the dielectric constant of P(BMI-C36) is 2.558 @ 10 MHz. The aromatic polybismaleimides possessed better thermal stability, among which, the 5 % thermal decomposition temperature (T d,5) of P(BMI-70) was 513.5 °C, and the residual carbon rate at 800 °C was 44.6 %. In additional, water absorption was studied and their saturated water absorption was less than 4 %. [Display omitted] [ABSTRACT FROM AUTHOR]

Structural transformations in different coal ranks during low temperature oxidation (≤ 210°C) are crucial to understand the spontaneous combustion of coal and related environmental problems. The in-situ Fourier transform infrared (FTIR) technique was used to highlight the variations of aromatic, aliphatic, oxygen functional groups, and hydrogen bonds of different coal ranks spanning from lignite to anthracite. Chemical changes were observed at real-time experimental conditions. Characteristic temperature points were selected as the point where obvious gas changes occurred. Structural parameters were determined by fitting FTIR spectra. The band of highly substituted aromatic rings had a direct correlation with low rank coals. The degree of substitution (DOS) of aromatic sites with alkyl groups showed a good power function correlation with fixed carbon content. Aliphatic carbon changes displayed similar trends with different coal ranks. Moreover, increasing coalification decreased the oxygen functional parameter 'C'. The 'C' value of samples with high oxygen content increased with temperature, caused due to the oxidation of aliphatic structures. The fitting areas of the 3600–3000 cm−1 region reduced with increasing coal rank. The aromatic structures changed more significantly with temperature in low-rank coal than in high-rank coal. [ABSTRACT FROM AUTHOR]

The application of electrodialysis for tartrate stabilization and reagent-free acidity correction of wine and juices is attracting increasing interest. New aliphatic membranes CJMC-3 and CJMA-3 and aromatic membranes CSE and ASE were tested to determine their suitability for use in these electrodialysis processes and to evaluate the fouling of these membranes by wine components for a short (6–8 h) operating time. Using IR spectroscopy, optical indication and measurement of surface contact angles, the chemical composition of the studied membranes, as well as some details about their fouling by wine components, was clarified. The current–voltage charsacteristics, conductivity and water-splitting capacity of the membranes before and after electrodialysis were analyzed. We found that in the case of cation-exchange membranes, complexes of anthocyanins with metal ions penetrate into the bulk (CJMC-3) or are localized on the surface (CSE), depending on the degree of crosslinking of the polymer matrix. Adsorption of wine components by the surface of anion-exchange membranes CJMA-3 and ASE causes an increase in water splitting. Despite fouling under identical conditions of electrodialysis, membrane pair CJMC-3 and CJMA-3 provided 18 ± 1 tartrate recovery with 31 · 10−3 energy consumption, whereas CSE and ASE provided 20 ± 1% tartrate recovery with an energy consumption of 28 · 10−3 Wh, in addition to reducing the conductivity of wine by 20 ± 1%. The casting of aliphatic polyelectrolyte films on the surface of aromatic membranes reduces fouling with a relatively small increase in energy consumption and approximately the same degree of tartrate recovery compared to pristine CSE and ASE.

The present study describes the syntheses of a series of novel symmetrical bisthiadiazolines 4(a-j) built around the ten types of aliphatic/aromatic linkers. These bisheterocycles have been systematically synthesized by using the ring closure reactions of bisthiosemicarbazones 3(a-j) by refluxing under the acetic anhydride (Ac2O) medium. The latter have been efficiently achieved through the condensation reactions of appropriate dinaphthaldehydes 2(a-j) with thiosemicarbazide in the presence of dry MeOH/HCl conditions. The treatment of 2-hydroxy-1-naphthaldehyde 1 with suitable dihalogenated reagents under the anhydrous K2CO3/Bu4N+I−/dry acetone medium furnished new intermediates 2(a-j). IR, 1H NMR, 13C NMR, ESI-MS & elemental analyses spectral data were in full agreement to their proposed structures. The aliphatic chains linked bisthiadiazolines 4(a-f) displayed significant antioxidant potencies while aromatic spacers based products 4(g-j) were found to exhibit better antimicrobial properties. The molecular docking simulations have also been carried out to visualize the possible interaction of most active antimicrobial compound 4g at the active sites of Staphylococcus aureus tyrosyl-tRNA synthetase protein (PdB: 1JIL).

Owing to several presumed health-promoting biological activities, increased attention is being given to natural plant chemicals, especially those frequently entering the human diet. Glucosinolates (GLs) are the main bioactive compounds found in broccoli (Brassica oleracea L. var. italica Plenck). Their regular dietary assumption has been correlated with reduced risk of various types of neoplasms (lung, colon, pancreatic, breast, bladder, and prostate cancers), some degenerative diseases, such as Alzheimer's, and decreased incidence of cardiovascular pathologies. GL's synthesis pathway and regulation mechanism have been elucidated mainly in Arabidopsis. However, nearly 56 putative genes have been identified as involved in the B. oleracea GL pathway. It is widely recognized that there are several pre-harvest (genotype, growing environment, cultural practices, ripening stage, etc.) and post-harvest (harvesting, post-harvest treatments, packaging, storage, etc.) factors that affect GL synthesis, profiles, and levels in broccoli. Understanding how these factors act and interact in driving GL accumulation in the edible parts is essential for developing new broccoli cultivars with improved health-promoting bioactivity. In this regard, any systematic and comprehensive review outlining the effects of pre- and post-harvest factors on the accumulation of GLs in broccoli is not yet available. Thus, the goal of this paper is to fill this gap by giving a synoptic overview of the most relevant and recent literature. The existence of substantial cultivar-to-cultivar variation in GL content in response to pre-harvest factors and post-harvest manipulations has been highlighted and discussed. The paper also stresses the need for adapting particular pre- and post-harvest procedures for each particular genotype in order to maintain nutritious, fresh-like quality throughout the broccoli value chain.

Abstract Background NMDA receptor modulation by hydrocarbons is associated with a molar water solubility cut-off. Low-affinity phenolic modulation of GABAA receptors is also associated with a cut-off, but at much lower molar solubility values. We hypothesized that other anesthetic-sensitive ion channels exhibit distinct cut-off effects associated with hydrocarbon molar water solubility, and that cut-off values are comparatively similar between related receptors than phylogenetically distant ones. Methods Glycine or GABAA receptors or TREK-1, TRESK, Nav1.2, or Nav1.4 channels were expressed separately in frog oocytes. Two electrode voltage clamp techniques were used to study current responses in the presence and absence of hydrocarbon series from eight functional groups with progressively increasing size at saturated aqueous concentrations. Null response (cut-off) was defined by current measurements that were statistically indistinguishable between baseline and hydrocarbon exposure. Results Ion channels exhibited cut-off effects associated with hydrocarbon molar water solubility in the following order of decreasing solubility: Nav1.2 ≈ Nav1.4 ≳ TRESK ≈ TREK-1 > GABAA >> glycine. Previously measured solubility cut-off values for NMDA receptors were intermediate between those for Nav1.4 and TRESK. Conclusions Water solubility cut-off responses were present for all anesthetic-sensitive ion channels; distinct cut-off effects may exist for all cell surface receptors that are sensitive to volatile anesthetics. Suggested is the presence of amphipathic receptor sites normally occupied by water molecules that have dissociation constants inversely related to the cut-off solubility value. Poorly soluble hydrocarbons unable to reach concentrations sufficient to out-compete water for binding site access fail to modulate the receptor.

Aliphatic di- and polyisocyanates are crucial chemical ingredients in many industrial processes and are a well-recognized cause of occupational asthma. Serologic detection of "chemical epitopes" in biological samples could serve as an exposure surveillance approach toward disease prevention, and thus we sought to generate aliphatic isocyanate-specific monoclonal antibodies (mAbs). Three hybridomas were generated from Balb/c mice immunized with a commercial product containing a combination of uretdione, homopolymer, and monomeric forms of hexamethylene diisocyanate (HDI). Three stable hybridomas were subcloned by limiting dilution, two secreting IgG1κ and one secreting IgMκ mAb that bind aliphatic di- and polyisocyanates (conjugated to albumin), but not aromatic toluene or methylene diphenyl diisocyanate (TDI or MDI). Each mAb demonstrates slight differences in epitope specificity, for example, recognition of hydrogenated MDI (HMDI) or different carrier proteins (transferrin, actin) reacted with vapor phase HDI, and is encoded by unique recombination of different germline antibody genes, with distinct complementary determining regions. By western blot, all three mAbs detect a molecule with characteristics of an albumin adduct uniquely in urine from mice skin exposed to a mixture of aliphatic di- and polyisocyanate. Together, the data define molecular determinants of humoral immune recognition of aliphatic di- and polyisocyanates through new mAbs, which will serve as useful research reagents and may be applicable to future exposure surveillance efforts. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide was synthesized and functionalized with FeSO4⋅7H2O to form a reduced graphene oxide/iron oxide hybrid composite. The hybrid composite was extensively characterized using various techniques. Its application for transfer hydrogenation of various ketones was studied. The investigation showed that it serves as a good catalyst for transfer hydrogenation of aromatic and some aliphatic ketones resulting in excellent isolated yields (97–99%) of products. It is magnetically separable showing good reusability. The products were characterized and compared with authentic ones. [ABSTRACT FROM AUTHOR]

Numerous disinfection by-products (DBPs) are formed from reactions between disinfectants and organic/inorganic matter during water disinfection. More than seven hundred DBPs that have been identified in disinfected water, only a fraction of which are regulated by drinking water guidelines, including trihalomethanes, haloacetic acids, bromate, and chlorite. Toxicity assessments have demonstrated that the identified DBPs cannot fully explain the overall toxicity of disinfected water; therefore, the identification of unknown DBPs is an important prerequisite to obtain insights for understanding the adverse effects of drinking water disinfection. Herein, we review the progress in identification of unknown DBPs in the recent five years with classifications of halogenated or nonhalogenated, aliphatic or aromatic, followed by specific halogen groups. The concentration and toxicity data of newly identified DBPs are also included. According to the current advances and existing shortcomings, we envisioned future perspectives in this field. [Display omitted] • The progress in identification of unknown DBPs in recent five years was reviewed. • The new DBPs were classified based on halogenation followed by aliphatic/aromatic. • Future opportunities in identification of unknown DBPs were discussed. • The species, origins, and identification methods of unknown DBPs were envisioned. [ABSTRACT FROM AUTHOR]

The present study investigated the changes in total and individual glucosinolates (GSLs) in roots and leaves of different clubroot-resistant and -susceptible oilseed rape cultivars following artificial inoculation with Plasmodiophora brassicae isolates with different virulence. The results showed significant differences in clubroot incidence and severity as well as in the amount of total and individual glucosinolates between oilseed rape cultivars in response to virulence of the pathogen. Single among with total aliphatic and total indolic glucosinolate contents were significantly lower in leaves of susceptible cultivars compared to resistant ones due to the infection. Similarly, single and total aliphatic as well as indolic glucosinolate contents in roots were lower in susceptible cultivars compared to resistant cultivars analyzed. The different isolates of P. brassicae seem to differ in their ability to reduce gluconasturtiin contents in the host. The more aggressive isolate P1 (+) might be able to suppress gluconasturtiin synthesis of the host in a more pronounced manner compared to the isolate P1. A possible interaction of breakdown products of glucobrassicin with the auxin receptor transport inhibitor response 1 (TIR1) is hypothesized and its possible effects on auxin signaling in roots and leaves of resistant and susceptible cultivars is discussed. A potential interplay between aliphatic and indolic glucosinolates that might be involved in water homeostasis in resistant cultivars is explained.

Abstract The Panel on Food Additives and Flavourings (FAF Panel) of the European Food Safety Authority was requested to evaluate the genotoxic potential of the flavouring substances from subgroup 1.2.1 of FGE.19 in the Flavouring Group Evaluation 204 (FGE.204). In the present revision of this FGE (FGE.204Rev1), the FAF Panel evaluated new data provided by Industry following a request from the former Panel on Food Contact materials, Enzymes, Flavourings and Processing Aids (CEF Panel). This request followed from positive results in an in vitro micronucleus test for clastogenicity and a negative result, but with no proof of bone marrow exposure, in an in vivo micronucleus assay for the representative substance 7‐methyl‐3‐octenone‐2 [FL‐no: 07.177]. Subsequently, the Industry submitted an in vivo comet assay which was considered equivocal in the liver. The study was repeated confirming that 7‐methyl‐3‐octenone‐2 [FL‐no: 07.177] did not induce primary DNA damage in the liver and duodenum. Based on the available data, the Panel concluded that the concern for genotoxicity can be ruled out for [FL‐no: 07.177] and the 15 structurally related substances [FL‐no: 02.102, 02.193, 07.044, 07.048, 07.082, 07.104, 07.105, 07.106, 07.107, 07.121, 07.139, 07.187, 07.188, 07.244, 07.258] which can be evaluated through the Procedure for flavouring substances.

A new Fe(II) Schiff base complex anchored on mont-K10 (Fe@imine-mont-K10) was synthesized and extensively characterized by FTIR, powder X-ray diffraction, SEM–EDX, TEM, ESR, X-ray photoelectron spectroscopy (XPS), BET surface area measurement, solid state 29Si NMR and ICP-AES analysis. The catalytic activity of the complex was investigated for hydrogenation of ketones. The results indicated that it exhibited good catalytic activity for hydrogenation of aromatic as well as aliphatic ketones in i-PrOH/CH3CN (1:1) using Na-i-OPr as base at 80 °C resulting in moderate to excellent isolated yields (51–99%) of their corresponding products. The catalyst shows good reusability. [ABSTRACT FROM AUTHOR]

Abstract The objective of the present study is to explore the effects of the minor addition of 1-pentanol and benzyl alcohol, classified respectively as aliphatic and aromatic type alcohols based on the classified hydroxyl group position in their molecular structure. Simarouba glauca and diesel blends (B20 and B40) were prepared and tested to study the CI engine performance, emission and combustion characteristics under different load conditions. To each of the four combination fuel samples prepared for B20 and B40, 1-pentanol and benzyl alcohol additives were added at 5% and 10% concentrations by volume. Experimental tests for all of the different fuels were performed in a single cylinder, four-stroke and constant speed CI engine and the engine characteristics were compared with diesel and biofuel blends. The experimental study reveals that the poor performance of B20 and B40 is enhanced with 1-pentanol (P) and benzyl alcohol (Bn) addition. The improvement in performance is considerable with an increase in the concentrations of alcohol in B20 and B40 blends. Higher HC, CO and smoke emissions associated with B20 and B40 blend fuels are reduced with alcohol addition. NOx emissions are also reduced with the addition of alcohol blends and 1-pentanol shows more promising results in terms of low NOx emissions compared to benzyl alcohol. Alcohol addition with B20 and B40 extended the ignition delay period due to low cetane number. However, combustion phasing is reduced as a result of improved combustion. The outcome of this research work is that poor combustion characteristics of the biofuel-diesel blend can be improved with the minor addition of aliphatic and aromatic alcohol. Except for comparatively higher NOx emissions, benzyl alcohol showed promising results in terms of performance parameters like efficiency, emission and combustion improvement. [ABSTRACT FROM AUTHOR]

The study establishes an adequate monomer combination for achieving the best balance of properties required in obtaining polyimide alignment layers for display devices. The molecular design of some aliphatic/aromatic polyimides was performed by using dianhydride monomers with distinct configurations in terms of rigidity, size, and symmetry. The polyimides based on semi-flexible and nonsymmetric dianhydride moieties present lower refractive index and dielectric constant (<3) than those obtained from symmetric and rigid dianhydride units. This determines faster traveling of visible and microwave radiations as required for liquid crystal alignment purposes. The interactions of samples with the N-(4-Methoxybenzylidene)-4-butylaniline, cyanobiphenyl, and 4-pentyl-4-cyanobiphenyl nematics were assessed. The analyzed polyimides have higher surface tensions than the ones of the liquid crystals, determining a parallel arrangement of the nematic molecules. As the dispersive interactions at the polymer surface are lower, the work of spreading is higher as a result of improved adhesion of liquid crystal with the polyimide alignment layer. The sample containing rigid, symmetric, noncoplanar dianhydride units (PI.4) and the one based on semi-flexible, nonsymmetric dianhydride moieties are the most transparent for visible and microwave radiations, allowing low cohesion interaction at interface with nematics. These aspects recommend the two studied polyimides as candidates for alignment layers. [ABSTRACT FROM AUTHOR]

Designing the novel conductive and biodegradable scaffolds based on star-like hyperbranched terpolymers of aliphatic polyester-poly(D,L-lactide)-polyaniline (S-HAP-PLA-PANI) was the purpose of this research. The electroactivity of tissue engineering scaffold, which in the current work was for the presence of PANI, is an essential factor in its performance because the electrical signals are the pivotal physiological stimuli that control the adhesion and differentiation of various cell types. Star-shaped polymers have attracted conspicuous attention, thanks to their low-cost, well-defined highly functionalized structures and low crystallinity, and they also could be an interesting alternative to the linear analogs for their interaction with surrounding tissue and faster degradation rate. In the present work, after 12 weeks, the mass loses for S-HAP-PLA-PANI sample were calculated to be 45%. Scaffolds based on S-HAP-PLA-PANI/PLA nanofibers having the average diameter of 70-200 nm and electrical conductivity of 0.05 S cm−1 imitated the natural microenvironment of extra cellular matrix to regulate the cell attachment, proliferation, and differentiation. [ABSTRACT FROM AUTHOR]

Pyrolysis of pine wood was carried out at different temperatures and the yields of solid (biochar), liquid (tar and pyrolysed water) and gas products were determined. Temperature around 500 °C was determined as an optimal heating temperature of pyrolysis and approximately 27.1% hard residue (biochar), 21.46% tar, 20.04% pyrolysed water and 31.30% gas were obtained by pyrolysis. The thermal stability indices of pine wood are relatively low, which are indications of its low thermal stability and high yield of volatile matter (Vdaf = 90.3%). The thermal stability indices of pyrolysis of solid residue show that it is characterised by a very high thermal stability than its initial sample, for example, there was an increase of T5% 7.7 and T15% 3.8 times. The chemical composition of pyrolysed tar of pine wood has also been determined. Were obtained 4 different fractions with varying boiling temperature ranges of pine wood pyrolysed tar and have determined the yields of each fraction. Neutral tar was analysed by GC/MS and 20 aliphatic compounds, 25 aromatic compounds and 18 polar compounds were determined. [ABSTRACT FROM AUTHOR]

Novel lipids were isolated from the unsaponifiable matter extracted from leaves of Artabotrys odoratissimus (R.Br) by using n-hexane. The two known compounds, one new carboxyester and two monoesters were the new lipids identified by spectral (IR, 1H NMR, 13C NMR spectra, mass spectrum, elemental analysis) and chemical analysis. The carboxyester was identified as 1-carboxy-heneicosane pentadecanoate and two monoesters were identified as hexyl pentaicosanote and pentyl pentaicosanoate. Antimicrobial activities were assessed for all extracts and isolated compounds and showed variable activity. These are novel compounds and being reported first time by us.

Selenium (Se) is an essential micronutrient for human health, entering the diet mainly through the consumption of plant material. Members of the Brassicaceae are Se-accumulators that can accumulate up to 1g Se kg−1 dry weight (DW) from the environment without apparent ill effect. The Brassicaceae also produce glucosinolates (GSLs), sulfur (S)-rich compounds that benefit human health. Radish (Raphanus sativus) has a unique GSL profile and is a Se-accumulating species that is part of the human diet as sprouts, greens and roots. In this report we describe the effects of Se-fertilisation on GSL production in radish during five stages of early development (from seed to mature salad greens) and on the transcript abundance of eight genes encoding enzymes involved in GSL metabolism. We tentatively identified (by tandem mass spectrometry) the selenium-containing glucosinolate, 4-(methylseleno)but-3-enyl glucosinolate, with the double bond geometry not resolved. Two related isothiocyanates were tentatively identified by Gas Chromatography-Mass Spectrometry as (E/Z?) isomers of 4-(methylseleno)but-3-enyl isothiocyanate. Se fertilisation of mature radish led to the presence of selenoglucosinolates in the seed. While GSL concentration generally reduced during radish development, GSL content was generally not affected by Se fertilisation, aside from the indole GSL, indol-3-ylmethyl glucosinolate, which increased on Se treatment, and the Se-GSLs, which significantly increased during development. The transcript abundance of genes involved in aliphatic GSL biosynthesis declined with Se treatment while that of genes involved in indole GSL biosynthesis tended to increase. APS kinase transcript abundance increased significantly in three of the four developmental stages following Se treatment. The remaining genes investigated were not significantly changed following Se treatment. We hypothesise that increased APS kinase expression in response to Se treatment is part of a general protection mechanism controlling the uptake of S and the production of S-containing compounds such as GSLs. The upregulation of genes encoding enzymes involved in indole GSL biosynthesis and a decrease in those involved in aliphatic GSL biosynthesis may be part of a similar mechanism protecting the plant’s GSL complement whilst limiting the amount of Se-GSLs produced.

Interfacial tension between hydrocarbon liquids and salt water is a very important property for many industrial applications, especially in petroleum industry. Interfacial tension, in addition to other factors, has direct impact on displacement process in porous media so thus on oil recovery. Very recently, the salinity of injection brine has been regarded as a key factor in oil recovery using low salinity water flooding process. Decrease in the interfacial tension between crude oil and injection brine at low salinity condition might be a reason behind recovery improvement as suspected by some researchers; but there are also other effects associated with low salinity water flooding like wettability alteration, fine migration, mineral dissolution etc. It is suspected that the interaction of polar components at oil-water interface lead to the reduction of interfacial tension. However, the actual mechanism is not known and still under research. The main objective of this work is to determine the effect of salt concentration and type of ions present in an aqueous phase on the interfacial tension between pure hydrocarbon liquids and water. Different hydrocarbon liquids, such as aliphatic and aromatics, have been tested to understand the interaction of monovalent and divalent salts on the interfacial tension. The study reports the interfacial tension of five pure hydrocarbon liquids against solutions of three different salts (NaCl, MgCl 2 and CaCl 2 ) over a wide range of salinities. The interfacial tension measurements were done using Wilhelmy plate method by a dynamic contact angle tensiometer. All the experiments were conducted at room temperature and atmospheric pressure. The results lead us to the view that there is low a salinity concentration where the hydrocarbon/brine interfacial tension shows a minimum value. The type of salt also has a significant effect on interfacial tension of aliphatic and aromatic hydrocarbons. Monovalent salt found to be effective in reducing interfacial tension of aliphatic hydrocarbons while divalent salts were found to be effective for aromatic hydrocarbons. The possible mechanism for the reduction in IFT at low salt concentration has also been explained using Gibb's adsorption isotherm. In addition, the trend in IFT has been explained in the light of well-known Jones-Ray effect. [ABSTRACT FROM AUTHOR]

Recently, deep eutectic solvents (DESs) have proven to be excellent extracting agents in the separation of aromatic components from their mixtures with aliphatic compounds. The tunable properties of the DESs allow to tailor-make optimal solvents for this application. In this work type III DESs, based on chloride quaternary ammonium salts (tetramethylammonium chloride, tetraethylammonium chloride, tetrabutylammonium and tetrahexylammonium chloride) as hydrogen bond acceptor molecules and polyols (ethylene glycol and glycerol) as hydrogen bond donor molecules were used. The liquid-liquid equilibrium (LLE) data of the system {hexane + benzene + DES} was measured at room temperature and atmospheric pressure. The solute distribution ratio and the selectivities were calculated and compared. The highest solute distribution ratios were obtained for salts with long alkyl chain length as hydrogen bond acceptor molecules and for ethylene glycol as hydrogen bond donor molecules. COSMO-RS was used for the prediction of the LLE data of the studied systems. It was found that both the LLE data and the solute distribution ratio of the ternary systems containing DESs can be qualitatively well predicted using this model. Moreover, the LLE data was quantitatively predicted within a root mean square error of 10 wt% without the need of any experimental data. This implies that COSMO-RS is an effective screening tool for the optimization of the separation process of aromatic components from {aliphatic + aromatic} mixtures using DESs as extracting agents. [ABSTRACT FROM AUTHOR]

Abstract The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 29 flavouring substances in the Flavouring Group Evaluation 18, as laid down in Commission Regulation (EC) No 1565/2000. None of the substances were considered to have a genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure‐activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. This revision deals with new toxicity data on the supporting substance myrcene [FL‐no: 01.008], providing an appropriate NOAEL for the evaluation of candidate substance [FL‐no: 02.146]. The Panel concluded that all 29 substances [FL‐nos: 02.041, 02.052, 02.054, 02.120, 02.123, 02.129, 02.140, 02.146, 02.144, 02.147, 02.149, 02.150, 02.168, 02.171, 02.181, 02.184, 02.197, 02.203, 02.206, 02.219, 02.226, 02.230, 02.253, 09.171, 09.356, 09.614, 09.617, 09.671 and 09.808] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. However, based on mTAMDI calculations, for all candidate substances except [FL‐no: 02.146] more reliable intake data are required for a re‐evaluation. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. For four substances [FL‐nos: 02.129, 02.147, 02.168, 02.197] additional information on purity criteria and/or stereoisomeric composition is required.

Abstract The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 41 flavouring substances in Flavouring Group Evaluation 21, Revision 5, using the Procedure in Commission Regulation (EC) No 1565/2000. This revision was carried out because of the inclusion of the assessment of new toxicity data on the candidate substances, 5‐ethylthiophene‐2‐carbaldehyde [FL‐no: 15.074] and 2‐pentylthiophene [FL‐no: 15.096]. These data on 5‐ethylthiophene‐2‐carbaldehyde [FL‐no: 15.074] should cover 2‐acetylthiophene [FL‐no: 15.040] and 2‐propionylthiophene [FL‐no: 15.097]. These data on 2‐pentylthiophene [FL‐no: 15.096] should cover 2‐butylthiophene [FL‐no: 15.045], 2‐hexylthiophene [FL‐no: 15.076] and 2‐octylthiophene [FL‐no: 15.093]. For two of the substances [FL‐no: 15.060 and 15.119] the Panel concluded that additional genotoxicity data are required. The remaining 39 substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure–activity relationships, intake from current uses, toxicological threshold of concern and available data on metabolism and toxicity. The Panel concluded that the 39 flavouring substances [FL‐no: 15.038, 15.039, 15.040, 15.044, 15.045, 15.050, 15.051, 15.052, 15.054, 15.055, 15.057, 15.058, 15.061, 15.062, 15.063, 15.067, 15.068, 15.069, 15.071, 15.074, 15.076, 15.078, 15.079, 15.080, 15.082, 15.084, 15.085, 15.086, 15.087, 15.089, 15.093, 15.096, 15.097, 15.098, 15.108, 15.115, 15.116, 15.118 and 15.135] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the Maximised Survey‐derived Daily Intake (MSDI) approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications, including complete purity criteria and identity for the materials of commerce, have been provided for all 41 candidate substances.

Abstract The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 14 flavouring substances in the Flavouring Group Evaluation 25, Revision 3, using the Procedure in Commission Regulation (EC) No 1565/2000. None of the substances was considered to have a genotoxic potential. This revision is made due to the inclusion of new toxicity data on the supporting substances β‐caryophyllene [FL‐no: 01.007] and myrcene [FL‐no: 01.008] considered in FGE.78Rev2 to cover the assessment of 4(10)‐thujene [FL‐no: 01.059], 2,6‐dimethylocta‐2,4,6‐triene [FL‐no: 01.035], cis‐3,7‐dimethyl‐1,3,6‐octatriene [FL‐no: 01.064] and 1‐octene [FL‐no: 01.070]. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure‐activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The Panel concluded that all 14 substances [FL‐no: 01.001, 01.027, 01.028, 01.033, 01.034, 01.035, 01.038, 01.039, 01.046, 01.054, 01.057, 01.059, 01.064, 01.070] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications including complete purity and identity criteria for the materials of commerce have been provided for all 14 candidate substances.

Abstract The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA), and to decide whether further evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present consideration concerns 21 aromatic, aliphatic and alicyclic hydrocarbons [FL‐no: 01.002, 01.003, 01.004, 01.005, 01.006, 01.007, 01.008, 01.009, 01.010, 01.016, 01.017, 01.018, 01.019, 01.020, 01.024, 01.026, 01.029, 01.040, 01.045, 01.061 and 01.077] evaluated by the JECFA in 2005. FGE.78Rev1 considered 24 substances, but 4‐methyl‐1,1′‐biphenyl (JECFA‐no: 1334) and biphenyl (JECFA‐no: 1332) [former FL‐no: 01.011 and 01.013] are no longer supported by Industry for use as a flavouring substance in Europe. Moreover 1‐methylnaphthalene [FL‐no: 01.014] is in the process of being deleted from the Union List. This revision is owing to additional genotoxicity data on β‐caryophyllene [FL‐no: 01.007] and 90‐day studies in rats on β‐caryophyllene [FL‐no: 01.007] and myrcene [FL‐no: 01.008]. The substances were evaluated through a stepwise approach that integrates information on structure‐activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The specifications for the materials of commerce are adequate for all substances. The Panel concluded that the 21 aromatic, aliphatic and alicyclic hydrocarbons [FL‐no: 01.002‐01.010, 01.016‐01.020, 01.024, 01.026, 01.029, 01.040, 01.045, 01.061 and 01.077] do not give rise to safety concern at their levels of dietary intake, estimated on the basis of the MSDI approach.

The selectivity of alkyl-substituted imidazolium cation-based ionic liquids (ILs) with different anion: TfN, PF, TfN and BF, namely 1-Butyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide ([BMIM][TfN]), 1-Butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF]), 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([EMIM][TfN]), 1-Methyl-3-octyl imidazolium tetrafluoroborate ([OMIM][BF]), was tested for the extraction of benzene, toluene and p-xylene(BTX) aromatics with hexane mixtures. Liquid-liquid equilibrium (LLE) data were determined for the six ternary mixtures {hexane (1)+BTX (2)+ILs (3)} at 298.15 K and atmospheric pressure. In addition, binary LLE data from 293.15 K to 318.15 K are also reported for the system {hexane (1)+[BMIM][TfN] (2)}. The ternary experimental LLE data were satisfactorily correlated with the NRTL activity coefficient model. The degree of consistency of the tie lines was estimated by using the Othmer-Tobias equation, for which a good linear correlation coefficient (R) was obtained. As a result, the selectivity of ILs as potential solvents for the extraction of BTX from aliphatic components was found to be much higher than unity and PF anion showed higher selectivity compared to other anions. [ABSTRACT FROM AUTHOR]

New cholesterol side-functionalised polycarbonate polymers were synthesised by the ring-opening homo- and copolymerisation reaction of the cyclic monomer cholesteryl 5-methyl-2-oxo-1,3-dioxane-5-carboxylate andd,l-lactide using Sn(Oct)2as a catalyst. The chemical structures and average molecular weights of the cyclic monomer, homopolymer and block copolymers obtained in this study were characterised using FT-IR,1H NMR and gel permeation chromatographic measurement. The mesomorphism and mesophase structure were investigated with polarising optical microscopy, differential scanning calorimetry and X-ray diffraction measurement. As a result, the homopolymer and block copolymers showed an enantiotropic smectic A (SmA) phase. With the concentration of the lactide segment increasing, the glass transition temperature and isotropic temperature of the corresponding block copolymer all decreased. In addition, XRD suggested that the homopolymer and two block copolymers showed the SmA double-layer packing of side chains. [ABSTRACT FROM AUTHOR]

The objective of this paper was to create a comprehensive database for the adsorption of organic compounds by carbon nanotubes (CNTs) and to use the Linear Solvation Energy Relationship (LSER) technique for developing predictive adsorption models of organic compounds (OCs) by multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs). Adsorption data for 123 OCs by MWCNTs and 48 OCs by SWCNTs were compiled from the literature, including some experimental results obtained in our laboratory. The roles of selected OCs properties and CNT types were examined with LSER models. The results showed that the r 2 values of the LSER models displayed small variability for aromatic compounds smaller than 220 g/mol, after which a decreasing trend was observed. The data available for aliphatics was mainly for molecular weights smaller than 250 g/mol, which showed a similar trend to that of aromatics. The r 2 values for the LSER model on the adsorption of aromatic and aliphatic OCs by SWCNTs and MWCNTs were relatively similar indicating the linearity of LSER models did not depend on the CNT types. Among all LSER model descriptors, V term (molecular volume) for aromatic OCs and B term (basicity) for aliphatic OCs were the most predominant descriptors on both type of CNTs. The presence of R term (excess molar refractivity) in LSER model equations resulted in decreases for both V and P (polarizability) parameters without affecting the r 2 values. Overall, the results demonstrate that successful predictive models can be developed for the adsorption of OCs by MWCNTs and SWCNTs with LSER techniques. [ABSTRACT FROM AUTHOR]

This paper deals with the preparation of twelve aliphatic and substituted benzoic acids.the structures of these acids are confirmed by some physical methods. The main object of the paper is studying the possibility of association in these acids by physical methods,namely the UV,IR spectra,melting point and distribution methods. The mechanisms of association in these acids in benzene are happen by either hydrogen bonding alone or hydrogen bonding in addition to the ion induce dipole association methods.This depends on the structure of the acid and the temperature of the solution. The idea of ion induce dipole in founded here for the first times as suggested from the collected experimental results. Finally a suitable interpretation is given read any point as support by reference

[Display omitted] • Competition of convective and conductive modes of heat transfer across liquids with periodic properties. • Correlation of Thermal Lens signal with internal structures of molecules. • Correlation of Thermal Lens signal with inter and intramolecular interactions. • Structural effects on convective drifting of thermally excited molecules. • Establishing Thermal Lens measurements as a sensitive probe across a series of molecules liquids. Using thermal lens (TL) spectroscopy, we distinguish monohydric alcohols based on their molecular characteristics and thermophysical properties. We use both dual-beam Z-scan and time-resolved TL measurements to identify thermal signatures of the representative homologous series of aliphatic, cyclic, and aromatic alcohols. While, in aliphatic alcohols, TL signal amplitude depends strongly on the molecular size and chain length; for cyclic and aromatic alcohols, their photophysical characteristics exhibit dominance over the molecular influence of TL signal. The convective properties of short-chain molecules result in a characteristic trend in dual-beam experiments. Methanol displays the lowest steady-state TL signal due to its fast diffusive capabilities. At the same time, phenol shows the most prominent steady-state TL signal owing to its strong H-bonded cluster formation ability through resonant structures. TL measurements successfully distinguish alcohols belonging to the respective homologous series and additionally discern solvents with a similar number of carbon atoms belonging to different homologous series. [ABSTRACT FROM AUTHOR]