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In this study, we investigated the interaction between myofibrillar proteins (MPs) and selected alcohols (1-pentanol, 1-hexanol, and 1-heptanol). Only 1-heptanol exhibited the binding ability to MPs, and the binding ability significantly increased with increasing protein concentration (p 0.05). In addition, both static and dynamic quenching occurred during the interaction, with a red shift of the maximum absorption peak in the synchronous fluorescence spectra indicating a change in the microenvironment of the MPs. The results of circular dichroism measurements suggested that the interaction between MPs and 1-heptanol altered the secondary structure of the MPs. Furthermore, thermodynamic analysis showed that hydrogen bonding and van der Waals forces dominated the interaction between MPs and 1-heptanol, which was confirmed by the results of molecular docking/dynamics simulations. This study provides an in-depth understanding of the interaction between MPs and alcohols, which can help to improve the flavor control in meat.

Background Time-domain and non-linear methods can be used to quantify beat-to-beat repolarization variability but whether measures of repolarization variability can predict ventricular arrhythmogenesis in mice have never been explored. Methods Left ventricular monophasic action potentials (MAPs) were recorded during constant right ventricular 8 ​Hz pacing in Langendorff-perfused mouse hearts, in the presence or absence of the gap junction and sodium channel inhibitor heptanol (0.1, 0.5, 1 or 2 ​mM). Results Under control conditions, mean action potential duration (APD) was 39.4 ​± ​8.1 ​ms. Standard deviation (SD) of APDs was 0.3 ​± ​0.2 ​ms, coefficient of variation was 0.9 ​± ​0.8% and the root mean square (RMS) of successive differences in APDs was 0.15 ​± ​0.14 ​ms. Poincaré plots of APDn+1 against APDn revealed ellipsoid morphologies with a SD along the line-of-identity (SD2) to SD perpendicular to the line-of-identity (SD1) ratio of 4.6 ​± ​2.1. Approximate and sample entropy were 0.61 ​± ​0.12 and 0.76 ​± ​0.26, respectively. Detrended fluctuation analysis revealed short- and long-term fluctuation slopes of 1.49 ​± ​0.27 and 0.81 ​± ​0.36, respectively. Heptanol at 2 ​mM induced ventricular tachycardia in five out of six hearts. None of the above parameters were altered by heptanol during which reproducible electrical activity was observed (KW-ANOVA, P ​> ​0.05). Contrastingly, SD2/SD1 decreased to 2.03 ​± ​0.41, approximate and sample entropy increased to 0.82 ​± ​0.12 and 1.45 ​± ​0.34, and short-term fluctuation slope decreased to 0.82 ​± ​0.19 during the 20-s period preceding spontaneous ventricular tachy-arrhythmias (n ​= ​6, KW-ANOVA, P ​, Graphical abstract Image 1, Highlights • None of the parameters on variability determined using time-domain or non-linear analyses was altered by heptanol. • In the immediate periods preceding the onset of spontaneous ventricular tachycardia, the following changes were observed. • SD2/SD1 was decreased, approximate and sample entropy were increased, and short-term fluctuation slope was decreased. • These measures of repolarization variability could be used to predict impending ventricular arrhythmias in mouse hearts.

Probing the neural mechanisms that underlie each sensory system requires the presentation of perceptually appropriate stimulus concentrations. This is particularly relevant in the olfactory system as additional odorant receptors typically respond with increasing stimulus concentrations. Thus, perceptual measures of olfactory sensitivity provide an important guide for functional experiments. This study focuses on aliphatic alcohols because they are commonly used to survey neural activity in a variety of olfactory regions, probe the behavioral limits of odor discrimination, and assess odor-structure activity relationships in mice. However, despite their frequent use, a systematic study of the relative sensitivity of these odorants in mice is not available. Thus, we assayed the ability of C57BL/6J mice to detect a homologous series of primary aliphatic alcohols (1-propanol to 1-heptanol) using a head-fixed Go/No-Go operant conditioning assay combined with highly reproducible stimulus delivery. To aid in the accessibility of our data, we report the animal’s threshold to each odorant according to the 1) ideal gas condition, 2) nonideal gas condition (factoring in the activity of the odorant in the solvent), and 3) the liquid dilution of the odorant in the olfactometer. Of the odorants tested, mice were most sensitive to 1-hexanol and least sensitive to 1-butanol. These updated measures of murine sensitivity will hopefully guide experimenters in choosing appropriate stimulus concentrations for experiments using these odorants.

The self-labeling protein HaloTag has been used extensively to determine the localization and turnover of proteins of interest at the single-cell level. To this end, halogen-substituted alkanes attached to diverse fluorophores are commercially available that allow specific, irreversible labeling of HaloTag fusion proteins; however, measurement of protein of interest half-life by pulse-chase of HaloTag ligands is not widely employed because residual unbound ligand continues to label newly synthesized HaloTag fusions even after extensive washing. Excess unlabeled HaloTag ligand can be used as a blocker of undesired labeling, but this is not economical. In this study, we screened several inexpensive, low-molecular-weight haloalkanes as blocking agents in pulse-chase labeling experiments with the cell-permeable tetramethylrhodamine HaloTag ligand. We identified 7-bromoheptanol as a high-affinity, low-toxicity HaloTag-blocking agent that permits protein turnover measurements at both the cell population (by blotting) and single-cell (by imaging) levels. We show that the HaloTag pulse-chase approach is a nontoxic alternative to inhibition of protein synthesis with cycloheximide and extend protein turnover assays to long-lived proteins.

Hydrogen bonding in liquids of the constitution isomers of heptan-1-ol mixed with 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs), [Cnmim][NTf2], is investigated using both computational and experimental techniques. All-atom non-polarizable molecular-dynamics (MD) simulations predict that the hydrogen bonds gradually decay with increasing temperature. This decay is more pronounced for the branched alcohols and in the presence of the ionic liquids. The primary and linear isomer, heptan-1-ol, and its tertiary and bulky analogue 3-ethylpentan-3-ol are identified as the opposite extremes of the spectrum of hydrogen bonding stability in the bulk liquid. While neat heptan-1-ol exhibits strong hydrogen bonding at 350 K, 3-ethylpentan-3-ol is prone to hydrogen bonding decay already at 300 K. The presence of ionic liquids is found to affect the hydrogen bonding comparably as a 50 K temperature increase. Since the heat capacities of the associating liquids are very sensitive to any variation in hydrogen bonding strength and to the character of the hydrogen-bonded clusters in the bulk liquid, the calorimetric effort provides useful experimental data to confirm the results predicted by MD simulations. In this work, excess heat capacity is measured for equimolar single-phase mixtures of alcohols and ILs, and it differs largely in its sign and magnitude for individual heptanol isomers. Temperature trends of the excess heat capacities suggest that the stability of hydrogen bonding for individual heptanol isomers is temperature-shifted, based on their capability of hydrogen bonding. The predicted hierarchy of hydrogen bonding in individual alcohols and its impact on the excess heat capacity trends are qualitatively confirmed via thermodynamic modelling of the associative contribution to the excess heat capacities. These terms are found to predetermine the observed non-monotonous excess heat capacity trends.

Plasma membranes contain diverse nanoscale assemblies of lipid and protein domains. Specific localization of lipids and proteins in these domains is often essential for membrane function and integrity. Due to the nanoscale size and dynamic nature of membrane domains, identification of molecules residing in domains either is not possible with modern imaging techniques or requires advanced methods with high spatiotemporal resolution. Such methods need expensive equipment making these approaches inaccessible and thus difficult to implement at large scale. Here, we present a novel membrane fluidizer-induced clustering (MFIC) approach to identify the phase-preference of molecules in intact cell membranes. Experiments in phase-separated bilayers and live cells on molecules with known phase preference demonstrate that heptanol hyperfluidizes the membrane and stabilizes phase separation in cell membranes. The domain stabilization results in a transition of nano-to micron-sized clusters of associated molecules and allows identification of molecules localized in domains using routine microscopy techniques. This assay can be carried out on both genetically and extrinsically labelled molecules in live cell membranes, does not require any invasive sample preparation and can be carried out in 10-15 minutes. This inexpensive and easy to implement assay can be conducted at large-scale and will allow easy identification of molecules partitioning into domains.

Melatonin (MT) increases oocyte maturation by reducing reactive oxygen species level and enhancing oocyte antioxidant capacity. However, the mechanisms via which MT works are still poorly understood. In the present study, the effects of MT on the maturation rate and development ability of bovine oocytes were investigated. Then, the transcriptome of oocytes treated by MT was sequenced. Finally, the expression of gap junction protein alpha 4 (GJA4) protein and cAMP level were detected in bovine oocytes, and isoprenaline (enhancer of gap junctional intercellular communication (GJIC)) and heptanol (inhibitor of GJIC) were used to investigate the effect of MT on GJIC activity in bovine oocytes. Our results showed that MT significantly improved the maturation, developmental ability and mRNA expression of GJA4 of bovine oocytes. Meanwhile, MT significantly increased GJA4 protein level and cAMP level in bovine oocytes. In contrast to heptanol, both isoproterenol and MT significantly increased GJIC activity, nuclear maturation and the development ability of bovine oocytes. However, MT significantly restored the nuclear maturation and developmental ability of oocytes treated by heptanol. In conclusion, our results showed that MT improves the maturation and developmental ability of bovine oocytes by enhancing GJIC activity via up-regulating GJA4 protein expression in IVM progress.

The characteristic volatile profile of the Spanish Vinagre de Jerez (VJ), Vinagre de Condado de Huelva (VC) and Vinagre de Montilla-Moriles (VMM) protected designation of origin (PDO) wine vinegars has been studied and compared for the first time by headspace stir bar sorptive extraction-gas chromatography–mass spectrometry (HSSE-GC–MS). The possible markers of each category and PDO were assessed. Acetates were the majority group in all vinegars, while ketones, C13-norisoprenoids and volatile phenols showed significant differences between the three PDOs. Analysis of variance (ANOVA), heatmap and partial least squares-discriminant analysis (PLS-DA) were performed. According to these results, 1-heptanol, methyl nonanoate, 2-methylbutanoic acid, 2,2,6-trimethyl-cyclohexanone, trans-2-decenal, eucalyptol and α-terpineol, were the most significant compounds for differentiating of VC, diacetyl and acetoin, ethyl 3-ethoxypropanoate, 2- and 3-heptanone, 2-methyl-1-hexadecanol, 1-octen-3-ol, p-Cresol and camphene for VMM; and β-damascenone, 5-hydroxymethylfurfural, 3-heptanol, trans-2-hexen-1-ol and trans-2-hexen-1-yl acetate for VJ. Classification results showed that 100% of PDO samples were correctly classified, reaffirming the utility of the volatile profiles for classifying and authenticating wine vinegar PDOs., The authors would like to thank the Spanish Regulatory Councils of the wine vinegar PDOs for their invaluable help with the acquisition of the samples. This work was supported by “Consejería de Economía, Innovación y Ciencia, Junta de Andalucía” [P12-AGR-1601]; the FPU scholarship of “Ministerio de Educación, Cultura y Deporte” [FPU014/01247], and PIF scholarship of “I + D + i Universidad de Sevilla” [VI PPITUS 2017].

In this work, we successfully demonstrate high-yield synthesis of high-quality gold nanorods (Au NRs) with width ranging from 6.5 nm to 175 nm by introducing heptanol molecules as secondary templating agents during cetyltrimethylammonium bromide-templated, seeded growth method. The results show that an appropriate concentration of heptanol molecules not only alter the micellization behavior of CTAB in water, but also help silver ions impact the symmetry-breaking efficiency of additional Au-NP seeds in addition to enhancing the utilization of gold precursors. Moreover, the generality and versatility of the present strategy for synthesis of Au NRs with flexible controlled dimensions are further demonstrated by successful synthesis of Au NRs with the assistance of other fatty alcohols with properly long alkyl chains. Furthermore, when arrays of vertically aligned Au NRs with large width (AVA-Au120×90 NRs) are used as SERS substrates, they can achieve the ultralow limit of detection for crystal violet (10-16 M) with good reliability and reproducibility, and the rapid detection and identification of residual harmful substances.

6 pags., 7 figs., 1 tab., In order to determine the possible non-covalent influence of the alkali metal cation on the electrooxidation of 1-heptanol on gold in alkali metal hydroxides, 0.1 M MOH solutions, where M = Li, Na, K, Rb, and Cs, have been used. The charge-transfer resistance, determined by Electrochemical Impedance Spectroscopy, of heptanol oxidation at a fixed potential increased monotonically by a factor of 4 from LiOH to RbOH, that is, the heptanol oxidation current decreased. Since the degree of hydration of the OH group of the alcohol, as estimated by Molecular Dynamics Simulation, increased by a factor of 5 from LiOH to RbOH, it can be concluded that the decrease of the heptanol oxidation current from LiOH to RbOH is due to an increasing hydration of the heptanol OH group, which would hinder its access to the electrode surface. This result is in line with the previous finding [M.S. Ureta-Zañartu, C. Mascayano, C. Gutiérrez, doi:10.1016/j.electacta.2015.02.230] that the increase of the alcohol oxidation current at a fixed potential of linear saturated aliphatic alcohols from C1 to C7 on gold, both in a pH 11 buffer and in 0.1 M NaOH, increased with increasing chain length, that is, with decreasing hydration (because of the increasing hydrophobicity) of the alcoholic OH group., This work was supported by Fondo Nacional de Ciencia y Tecnología (FONDECYT-CONICYT-Chile), under Grants 1140207 and 1120379 and by Universidad de Santiago de Chile (USACh), Vicerrectoría de Inves-tigacion, Desarrollo e Innovacion (VRIDEI)-Grant USA 1899, 021941UZ- PAP and Direccion de Investigacion en Ciencia y Tecnología (DICYT)- USACh 021841UZ.

Sweet corn juice is becoming increasingly popular in China. In order to provide valuable health-related information to consumers, the nutritional and physicochemical characteristics of raw and boiled purple sweet corn juices were herein investigated. Sugars, antinutrients, total free phenols, anthocyanins, and antioxidant activity were analyzed by conventional chemical methods. The viscosity and stability of juices were determined by Ubbelohde viscosity meter and centrifugation, respectively. Boiling process could elevate viscosity, stability and sugar content, and reduce antinutrients, total free phenols, anthocyanins, and antioxidant activity in corn juice. In addition, short time boiling efficiently reduced the degradation of anthocyanins during subsequent refrigeration. The content of amino acids, vitamin B1/B2 and E were detected by High Performance Liquid Chromatography. Gas Chromatography Mass Spectrometry was used for the analysis of fatty acids and aroma compounds. Several aroma compounds not previously reported in corn were identified, including 1-heptanol, 2-methyl-2-butenal, (Z)-3-nonen-1-ol, 3-ethyl-2-methyl-1,3-hexadiene, and 2,4-bis(1,1-dimethylethyl)phenol. Interestingly, the boiling process had no apparent effect on the amino acids profile, but it caused a 45.8% loss of fatty acids in the juice by promoting the retention of fatty acids in the corn residue. These results provide detailed information that could be used for increasing consumers' knowledge of sweet corn juice, further development of sweet corn juice by food producers, and maize breeding programs.

In this work, the action of heptanol and ethanol was investigated in a two-dimensional (2D) model of cardiac tissue: the neonatal rat ventricular myocyte monolayer. Heptanol is known in electrophysiology as a gap junction uncoupler but may also inhibit voltage-gated ionic channels. Ethanol is often associated with the occurrence of arrhythmias. These substances influence sodium, calcium, and potassium channels, but the complete mechanism of action of heptanol and ethanol remains unknown. The optical mapping method was used to measure conduction velocities (CVs) in concentrations of 0.05–1.8 mM heptanol and 17–1342 mM ethanol. Heptanol was shown to slow the excitation wave significantly, and a mechanism that involves a simultaneous action on cell coupling and activation threshold was suggested. Whole-cell patch-clamp experiments showed inhibition of sodium and calcium currents at a concentration of 0.5 mM heptanol. Computer modeling was used to estimate the relative contribution of the cell uncoupling and activation threshold increase caused by heptanol. Unlike heptanol, ethanol slightly influenced the CV at clinically relevant concentrations. Additionally, the critical concentrations for re-entry formation in ethanol were determined.

The experimental liquid–liquid equilibrium (LLE) data of the quaternary systems ethanol + hexanol + decane + water, ethanol + hexanol + undecane + water, ethanol + heptanol + decane + water, and ethanol + heptanol + undecane + water were collected at 298.15 K under atmospheric pressure. The UNIQUAC model was used to regress the quaternary systems and acquire the binary interaction parameter, which was used to predict the LLE data of the six-component system. The predicted LLE data were compared with the experimental data, and the results showed they were in good agreement, which indicated that the binary interaction parameters acquired from the quaternary systems could predict the LLE data of the six-component system. The distribution coefficient and the selectivity showed that 65% ethanol aqueous solution was suitable for separating hexanol and heptanol from the hexanol–heptanol–decane–undecane mixture.

BACKGROUND Chronic, excessive ethanol intake has been linked with various electrical instabilities, conduction disturbances, and even sudden cardiac death, but the underlying cause for the latter is insufficiently delineated. METHODS We studied surface electrocardiography (ECG) in a community-dwelling cohort with moderate-to-heavy daily alcohol intake (grouped as >90g/day, ≤90g/day, and nonintake). RESULTS Compared with nonintake, heavier alcohol users showed markedly widened QRS duration and higher prevalence of QRS fragmentation (64.3%, 50.9%, and 33.7%, respectively, χ2 12.0, both p

Hydrolysis is the prevalent mechanism of decomposition of benzo- and caprinohydroxamic acids (HAs) in nitric and perchloric acid solutions and in the equilibrium organic phase based on heptanol, decanol, and 30% TBP in С13 paraffin diluent. In the nitric acid system with alcohols, HAs undergo autocatalytic oxidation at temperatures raised over 50°С. In the case of BHA, the process occurs in both phases taken separately and on their mixing. In the case of caprinohydroxamic acid poorly soluble in HNO3 solutions, the autocatalytic process occurs only at 70–80°С on mixing the phases; it tends to fade as the phase ratio n = О/A is increased from 1 to 10. This trend determines the conditions for Mo stripping in this system. In the practice of the 99Mo production, the stripping efficiency can be increased by repeated contact with the addition of non-salt complexing agents (H2O2, H2C2O4, CH3CONHOH) into the system.

Three pure heptanol isomers were studied using infrared spectroscopy: n -heptanol, 2,4-dimethyl-3-pentanol, and 3-ethyl-3-pentanol. In order to analyze the branching effect of heptanol, investigations on the two symmetric branched isomers have been performed. Branching and steric hindrance highly influence the aggregation in associating systems. Therefore, a systematic comparison with the linear molecule n -heptanol is performed to better understand the experimental data. The vibrational structures were studied in the spectral range from 650 to 4000 cm − 1 and the individual peaks were assigned to the corresponding vibrational modes of the molecules. The OH-stretching band is significantly narrower in the spectra of the branched alcohols compared to n -heptanol. In particular, the low frequency components of the band are absent. This is a result of the steric hindrance leading to a less pronounced hydrogen bonding network.

Measurements on density and viscosity at T = (293.15, 298.15, 303.15, 308.15 313.15, 318.15, 323.15, 328.15, and 333.15) K and the pressure P = 0.1 MPa for binary mixtures of n-dodecane or methylcyclohexane with 1-heptanol or cyclohexylmethanol have been carried out over the whole composition range. Densities were measured with a vibrating-tube densimeter. Viscosities were determined by an automatic microviscometer based on the rolling-ball principle. The excess molar volumes (VmE) and viscosity deviations (Δη) were calculated with experimental data and fitted to the Redlich–Kister equation. The results of these excess or deviation functions are explained by molecular interactions and structural effects. Freezing points were measured with a differential scanning calorimeter. The fundamental data, VmE and Δη can be used to study the nature of mixing behaviors between new hydrocarbon fuels.

Ethnopharmacological relevance Curcuma comosa Roxb. ( C. comosa ) or Wan Chak Motluk, Zingiberaceae family, has been used in Thai traditional medicine for the treatment of gynecological problems and inflammation. Aim of the study This study aimed to investigate the therapeutic potential of C. comosa by determining the changes in the lipid profiles in the ovariectomized rats, as a model of estrogen-deficiency-induced hyperlipidemia, after treatment with different components of C. comosa using an untargeted lipidomics approach. Materials and methods Lipids were extracted from the serum of adult female rats subjected to a sham operation (SHAM; control), ovariectomy (OVX), or OVX with 12-week daily doses of estrogen (17 β -estradiol; E 2 ), (3 R )-1,7-diphenyl-(4 E ,6 E )-4,6-heptadien-3-ol (DPHD; a phytoestrogen from C. comosa ), powdered C. comosa rhizomes or its crude ethanol extract. They were then analyzed by liquid chromatography–mass spectrometry, characterized, and subjected to the orthogonal projections to latent structures discriminant analysis statistical model to identify tentative biomarkers. Results Levels of five classes of lipids (ceramide, ceramide-1-phosphate, sphingomyelin, 1- O -alkenyl-lysophosphatidylethanolamine and lysophosphatidylethanolamine) were elevated in the OVX rats compared to those in the SHAM rats, while the monoacylglycerols and triacylglycerols were decreased. The E 2 treatment only reversed the levels of ceramides, whereas treatments with DPHD, C. comosa extract or powder returned the levels of all upregulated lipids back to those in the SHAM control rats. Conclusions The findings suggest the potential beneficial effects of C. comosa on preventing the increased ceramide levels in OVX rats, a possible cause of metabolic disturbance under estrogen deficiency. Overall, the results demonstrated the power of untargeted lipidomics in discovering disease-relevant biomarkers, as well as evaluating the effectiveness of treatment by C. comosa components (DPHD, extract or powder) as utilized in Thai traditional medicine, and also providing scientific support for its folklore use.

Alternatives of fossil fuel resources as renewable biodiesel fuel and alcohols represents latest technology to be developed associated with the declining of fossil fuel resources along with higher crude oil price. In this study, four-stroke, single cylinder, and direct injection diesel engine performance and emissions are evaluated. The engine was running at variable speeds (1600-3000 rpm). 15% and 25% of pentanol and heptanol were added to the diesel-biodiesel mixture. The experimental results showed increasing in brake specific fuel consumption with the increasing of higher mass fractions of alcohol blends, which is attributed to the decreasing the lower heating value (LHV) of the blends. Higher brake thermal efficiency compared to diesel fuel was produced. An expressive reduction in carbon monoxide (CO) of (16.1% - 46.6% vol.) with total unburned hydrocarbons (UHC) decrease of (7.4% - 25.3% ppm), and nitric oxides (NOx) of (8.5% - 23.5% ppm). Biodiesel and alcoholic blends are suitable to be used as alternatives to diesel without the need for any modifications in conventional diesel engines.

Six corn starch inclusion complexes were synthesized using small nonpolar or weak polar aroma compounds (heptanolide, carvone and menthone) and small polar aroma compounds (linalool, heptanol and menthol). The objectives of this study were to (a) investigate the ability of corn starch to form inclusion complexes with these aroma compounds and (b) characterize the structure of the corn starch inclusion complexes. RESULTS The resulting inclusion ratios were 75.6, 36.9, 43.8, 91.9, 67.2 and 54.7% for heptanolide, carvone, menthone, linalool, heptanol and menthol respectively. The inclusion complexes had laminated structures with a certain amount of holes or blocky constructions. Compared with gelatinized corn starch, the transition temperatures, peak temperatures and enthalpies of the inclusion complexes were significantly different. The major peak of C?O at 1771?cm?1 and significant peak shifts revealed the formation of inclusion complexes. X-ray diffractometry (XRD) analyses revealed that the crystallinity of corn starch?polar aroma compound inclusion complexes increased. Based on cross-polarization magic angle spinning 13C nuclear magnetic resonance (CP-MAS 13C NMR) results, novel peaks and chemical shifts were attributed to the presence of small aroma compounds, thereby confirming the formation of corn starch inclusion complexes. CONCLUSION Small nonpolar and polar aroma compounds can be complexed to corn starch. ? 2016 Society of Chemical Industry

The effects of different n-alkanol co-surfactants on the size, shape, composition and dynamics of reverse micelles (RMs) in cetyltrimethylammonium bromide (CTAB)/n-alkanol/n-hexane/water and CTAB/n-alkanol/n-pentane/water microemulsions were investigated using T2 relaxation and pulsed gradient stimulated echo nuclear magnetic resonance (NMR) measurements and molecular modelling. NMR T2 relaxation times and diffusion coefficients were determined for the surfactant and co-surfactant in these CTAB quaternary reverse microemulsions, for a range of medium chain length alcohol co-surfactants, from 1-butanol to 1-heptanol. These data revealed a slight RM size dependency on co-surfactant chain length, with RM sizes tending to decrease with increasing alcohol chain length. Molecular modelling of CTAB/n-alkanol/n-hexane/water RMs suggested a variation in RM shape with co-surfactant chain length, where those formed with pentanol were found to be least spherical and those formed with heptanol the most spherical. The NMR data also revealed differences in the behaviour of the micellar structures in the CTAB/n-pentanol/n-hexane/water reverse microemulsion, compared with the other reverse microemulsions in this study, where CTAB was found to be distributed between two environments, which then combined to form larger micelles. The origins of these differences remain unclear. Copyright © 2016 John Wiley & Sons, Ltd.

The first part of the current work systematically described the screening of different types of organic solvents as the supported liquid membrane (SLM) for electromembrane extraction (EME) of acidic drugs, including different alcohols, ketones, and ethers. Seven acidic drugs with a wide logP range (1.01-4.39) were selected as model substances. For the first time, the EME recovery of acidic drugs and system-current across the SLM with each organic solvent as SLM were investigated and correlated to relevant solvent properties such as viscosity and Kamlet and Taft solvatochromic parameters. Solvents with high hydrogen bonding acidity (α) and dipolarity-polarizability (π*) were found to be successful SLMs, and 1-heptanol was the most efficient candidate, which provided EME recovery in the range of 94-110%. Both hydrogen bonding interactions, dipole-dipole interactions, and hydrophobic interactions were involved in stabilizing the deprotonated acidic analytes (with high hydrogen bonding basicity and high dipole moment) during mass transfer across the SLM. The efficiency of the extraction normally decreased with increasing hydrocarbon chain length of the SLM, which was mainly due to increasing viscosity and decreasing α and π* values. The system-current during EME was found to be dependent on the type and the volume of the SLM. In contact with human plasma, an SLM of pure 1-heptanol was unstable, and to improve stability, 1-heptanol was mixed with 2-nitrophenyl octyl ether (NPOE). With this SLM, exhaustive EME was performed from diluted human plasma, and the recoveries of five out of seven analytes were over 91% after 10min EME. This approach was evaluated using HPLC-UV, and the evaluation data were found to be satisfactory.

Reprocessing of spent nuclear fuel usually employs the solvent extraction technique to recover fissile material, isolate other valuable radionuclides, recover precious metals, and remove contaminants. Efficient recovery of these species from highly radioactive solutions requires a detailed understanding of reaction conditions and metal speciation that leads to their isolation in pure forms. Due to the complex nature of these systems, identification of ideal reaction conditions for the efficient extraction of specific metals can be challenging. Thus, the development of experimental approaches that have the potential to reduce the number of experiments required to identify ideal conditions are desirable. In this study, a full-factorial experimental design was used to identify the main effects and variable interactions of three chemical parameters on the extraction of protactinium (Pa). Specifically we investigated the main effects of the anion concentration (NO3 -, Cl-) extractant concentration, and solution acidity on the overall extraction of protactinium by 2,6-dimethyl-4-heptanol (diisobutylcarbinol; DIBC) from both HCl and HNO3 solutions. Our results indicate that in HCl, the extraction of protactinium was dominated by the solution acidity, while in nitric acid the extraction was strongly effected by the [DIBC]. Based on our results, a mathematical model was derived, that describes the relationship between concentrations of anions, extractant, and solution acidity and the expected values of Pa distribution coefficients in both HCl and HNO3. This study demonstrates the potential to predict the distribution coefficient values, based upon a mathematical model generated by a full-factorial experimental design.

We investigated the dynamic changes in norisoprenoids and phenylalanine derivatives in off-vine Vidal blanc. Glycosidically bound as well as free-form volatile compounds were identified by GC-MS in two vintages. Thus, off-vine grape exhibited the development of four higher alcohols (viz. linalool oxide, 2-octanol, 1-pentanol, and 1-heptanol), C13-norisoprenoids (α-ionone), phenylalanine-derivates (2-phenylethanol), whereas β-ionone and geranial showed high correlation in on-vine grape. Freeze-thaw cycles and desiccation, two exterior stress affect volatile compound development, resulted in content fluctuations during late harvest. Interestingly, the total content of higher alcohols was higher in on-vine grapes than off-vine grapes in two vintages respectively. Interestingly, the content of higher alcohols was higher in off-vine samples in the 2016 and 2017 vintages. In terms of physicochemical parameters, off-vine Vidal showed results similar to those of on-vine sample. Nevertheless, sensorial impression of the grape juice was influenced by interaction of vintages and vine treatments.

Off-flavor after cold storage is the major consumer complaint relating to consumption of young coconut fruit. To understand its chemical basis, young coconut fruit were stored for up to 4 weeks at either 4 or 25 °C, followed by volatile analysis. Off-flavor was detected at 4 °C in both water and kernel tissue after one week of storage and then increased quickly thereafter. PatternHunter analysis showed that volatiles from the lipid oxidation pathway, heptanal, octanal, nonanal and heptanol, were positively correlated with the development of fruit off-flavor during cold storage. Lipoxygenase (LOX) and hydroperoxide lyase (HPL) were related to the formation of lipid-derived volatiles and activities of both of these enzymes were high in fruit during cold storage. Fruit wrapped with polyethylene (PE) film reduced LOX and HPL activities, reduced the concentrations of heptanal, octanal, nonanal and heptanol and inhibited off-flavor development relative to fruit wrapped with polyvinyl chloride (PVC) film.

In this study, the application of a mixture of organic solvents as a supported liquid membrane for improving the efficiency of the electromembrane extraction procedure was investigated. The extraction process was followed by high-performance liquid chromatography analysis of two model drugs (verapamil and riluzole). In this research, four organic solvents, including 1-heptanol, 1-octanol, 2-nitrophenyl octyl ether, and 2-ethyl hexanol, were selected as model solvents and different binary mixtures (v/v 2:1, 1:1 and 1:2) were used as the supported liquid membrane. The mixture of 2-ethyl hexanol and 1-otanol (v/v, 2:1) improved the extraction efficiency of model drugs by 1.5 to 12 times. It was found that extraction efficiency is greatly influenced by the level of electric current. In this study, for various mixtures of organic solvents, the electric current fluctuated between 50 and 2500 μA, and the highest extraction efficiencies were obtained with low and stable electric currents. Finally, the optimized extraction condition was validated and applied for the determination of model drugs in urine and wastewater samples.

A lack of well-established parameters and assessment values currently impairs biomonitoring of n-heptane exposure. Using controlled inhalation experiments, we collected information on urinary n-heptane metabolite concentrations and the time course of metabolite excretion. Relationships between external and internal exposure were analysed to investigate the suitability of selected metabolites to reflect n-heptane uptake. Twenty healthy, non-smoking males (aged 19-38 years, median 25.5) were exposed for 3 h to 167, 333 and 500 ppm n-heptane, each. Spot urine samples of the volunteers, collected before exposure and during the following 24 h, were analysed for heptane-2-one, 3-one, 4-one, 2,5-dione, 1-ol, 2-ol, 3-ol, and 4-ol using headspace solid phase dynamic extraction gas chromatography/mass spectrometry (HS-SPDE-GC/MS). Starting from median pre-exposure concentrations between0.5 (3-one) and 82.9 μg/L (4-one), exposure increased the concentrations for all parameters except for 4-one. Median post-exposure concentrations ranged up to 840.4 μg/L (2-ol) and decreased with half-lifes3 h after exposure. Non-parametric correlation analyses (n = 47, p 0.05) revealed weak to moderate associations of volume related metabolite excretion with external exposure for 2-one, 3-one and 2,5-dione (R = 0.332-0.753). Heptanol excretion was moderately associated with exposure (R ≥ 0.509) only after creatinine adjustment. Lacking association with external exposure impedes the use of 4-one as heptane biomarker, whereas 2-ol and 3-ol turned out to be sensitive indicators of exposure if creatinine correction is applied. By providing fundamental data on a panel of eight potential heptane metabolites, our study can help to promote biological monitoring of n-heptane exposure.

We have performed a 50 ns molecular dynamics simulation of a hyperbranched polymer, i.e. polyethyleneimine (PEI), inside inverse micelles formed with zwitterionic surfactants 3-(N, N-dimethyldodecylammoniio)-propansulfonate (SB) in heptanol. The runs were performed using the GROMACS simulation package. During simulation time the PEI molecule undergoes a conformational deformation and compaction. The radius of gyration of the PEI molecule finally located in the center of the water droplet is decreased from 3 nm to 1.7 nm. The unusual shrinking of the PEI molecule inside the micelle explains the extraordinary template effect of these microemulsions by making cadmium sulfide or gold clusters. (C) 2015 Elsevier B.V. All rights reserved.

The molecular structure and molecular forces in liquids and solutions, in particular, have been investigated by dielectric relaxation studies. The nature and strength of the molecular interactions have been established as the main cause for the chemical behaviour of compounds. The dielectric behaviour of dimethyl phthalate with heptanol in benzene solution has been studied at a microwave frequency of 9.36 GHz at different temperatures 303, 308, and 313 K. Different dielectric quantities such as dielectric constant (ε′), dielectric loss (ε″), static dielectric constant (ε 0), and dielectric constant at optical frequency (ε ∞) have been determined. The relaxation time τ has been calculated by both Higasi’s method and Cole–Cole method. The dielectric relaxation process can be treated as a rate process just like the viscous flow process. The complex system investigated shows the maximum relaxation time values at high temperatures by both Higasi’s method and Cole–Cole method. The molar free energies of activation of dipole moment (ΔF τ) and viscous force (ΔF η) have also been reported. The excess dipole moment is also determined. The excess dipole moment is a qualitative index for the presence of a hydrogen bond in the ternary system. The value of Δμ obtained in our study indicates the presence of hydrogen bonds between the components of the mixture. The system investigated shows that the relaxation time value increases with the increase in the concentration of solute.

The use of engineered cardiac tissue for high-throughput drug screening/toxicology assessment remains largely unexplored. Here we propose a scaffold that mimics aspects of cardiac extracellular matrix while preserving the contractility of cardiomyocytes. The scaffold is based on a poly(caprolactone) (PCL) nanofilm with magnetic properties (MNF, standing for magnetic nanofilm) coated with a layer of piezoelectric (PIEZO) microfibers of poly(vinylidene fluoride-trifluoroethylene) (MNF+PIEZO). The nanofilm creates a flexible support for cell contraction and the aligned PIEZO microfibers deposited on top of the nanofilm creates conditions for cell alignment and electrical stimulation of the seeded cells. Our results indicate that MNF+PIEZO scaffold promotes rat and human cardiac cell attachment and alignment, maintains the ratio of cell populations overtime, promotes cell-cell communication and metabolic maturation, and preserves cardiomyocyte (CM) contractility for at least 12 days. The engineered cardiac construct showed high toxicity against doxorubicin, a cardiotoxic molecule, and responded to compounds that modulate CM contraction such as epinephrine, propranolol and heptanol.

2-Mercapto-4-heptanol is a relatively new flavour compound that was recently approved as an ingredient by the Flavour and Extract Manufacturers’ Association in 2013. Its synthesis, which we have accomplished in four-steps, involved firstly a Grignard reaction of n-butanal with allylmagnesium chloride to prepare 1-hepten-4-ol. This was epoxidised and then converted to 1,2-epithio-4-heptanol, reduction of which with LiAlH4 gave the target compound in an overall yield of about 54%.

The effect of heat treatment and the presence or absence of fish skin on the volatile composition of Senegalese sole muscle was studied. The volatile profile of Senegalese sole at different storage periods was also evaluated. All samples were analysed by HS-SPME-GC-IT/MS and subjected to sensory evaluation. As expected, cooking enhanced the production/liberation of volatile compounds. Fish with the skin present, after cooking, had higher levels of sulphur compounds, 2-nonanone, ethyl octanoate and lower contents of hexanol and heptanol than skinned fish; moreover, the samples with the skin had a better overall sensory acceptability. During storage, changes on the volatile composition of Senegalese sole samples were found. The major differences were obtained after 2 weeks of storage. Compounds such as hexanal, heptanal, octanal, decanal, (E)-2-hexenal, (E)-2-decen-1-al, (E,Z)-2,6-nonadienal, benzaldehyde, 4-ethyl-benzaldehyde, 1-penten-3-ol, heptanol and (E)-2-octen-1-ol decreased after 2 weeks of storage, and other compounds, such as 3-methyl-1-butanal, 2-methyl-1-butanal, 2-heptanone, dimethyl trisulphide, dimethyl tetrasulphide and 2-methyltetrahydrothiophen-3-one increased. These differences were confirmed by sensory evaluation. Principal component analysis was applied to the chemical data.

We examined junctional conductance (gj) and its dependence on transjunctional voltage in gap junction (GJ) channels formed of wild-type connexin36 (Cx36) or its fusion form with green fluorescent protein (Cx36-EGFP) transfected in HeLa cells or endogenously expressed in primary culture of pancreatic β-cells. Only a very small fraction (∼0.8%) of Cx36-EGFP channels assembled into junctional plaques of GJs were open under control conditions. We found that short carbon chain n-alkanols (SCCAs) increased gj, while long carbon chain n-alkanols resulted in full uncoupling; cutoff is between heptanol and octanol. The fraction of functional channels and gj increased several fold under an exposure to SCCAs, or during reduction of endogenous levels of arachidonic acid (AA) by exposure to fatty acid-free BSA or cytosolic phospholipase A2 inhibitors. Moreover, uncoupling caused by exogenously applied AA can be rescued by BSA, which binds AA and other polyunsaturated fatty acids (PUFAs), but not by BSA modified with 1,2-cyclohexanedione, which does not bind AA and other PUFAs. We propose that under control conditions, Cx36 GJ channels in HeLa transfectants and β-cells are inhibited by endogenous AA, which stabilizes a closed conformational state of the channel that leads to extremely low fraction of functional channels. In addition, SCCAs increase gj by interfering with endogenous AA-dependent inhibition, increasing open probability and the fraction of functional channels.

Two-component interactions between (perfluorooctyl) heptanol (F8H7OH) and dipalmitoylphosphatidylcholine (DPPC), which is a major component of pulmonary surfactants in mammals, were systematically elucidated using Langmuir monolayers and Langmuir-Blodgett (LB) films of the compounds. The interactions such as the miscibility of the compounds and their phase behavior were examined from thermodynamic and morphological perspectives. The surface pressure (π )-molecular area (A) and surface potential (D V )-A isotherms of the binary monolayers containing F8H7OH in different mole fractions (XF8H7OH) were measured simultaneously. The excess Gibbs free energy of mixing of the two components was calculated from the π−A isotherms. The resulting isotherm data were employed to construct a two-dimensional (2D) phase diagram of the system. The phase diagram revealed that the transition pressure as well as the monolayer collapse pressure change with changes in XF8H7OH. These thermodynamic analyses suggested that the miscibility of the two components and the solidification of DPPC monolayers can be induced by the addition of F8H7OH. The phase behavior upon monolayer compression was observed morphologically in situ using Brewster angle microscopy (BAM) and fluorescence microscopy (FM), as well as ex situ using atomic force microscopy (AFM). Interestingly, the AFM-based analysis revealed the formation of monodispersed 2D micelles consisting of F8H7OH at low surface pressures.

Aristolochia trilobata L. is an aromatic plant, popularly known as “mil-homens”, and its essential oil (EO) is generally used to treat colic, diarrhea and dysentery disorders. We evaluated the antinociceptive effect of A. trilobata stem EO and of its major compound, the (R)-(-)-6-methyl-5-hepten-2-yl acetate (sulcatyl acetate: SA), using acetic acid (0.85%)-induced writhing response and formalin-induced (20 μL of 1%) nociceptive behavior in mice. We also evaluated the EO and SA effect on motor coordination, using the rota-rod apparatus. EO (25, 50 and 100 mg/kg) or SA (25 and 50 mg/kg) reduced nociceptive behavior in the writhing test (pppppp

We are presenting an exhaustive computational study regarding the effect of high pressure on normal alcohols with alkyl chains of increasing length from three to eight carbon atoms. 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol and 1-octanol were studied by means of classical molecular dynamics simulations applying pressures in the range 1-104 bar. The results of our calculations show that high pressure values affect the structure significantly. In particular, we have observed a marked difference in behaviour among alcohols with chain length below six and those with more than six-seven carbon atoms, being hexanol and heptanol a boundary case. We have named the model with the most shrunk alkyl chains as Asclepius form inspired by the Rod of Asclepius, the universally known symbol of medicine, where a snake is coiled around a rod.

Coalescence of bubbles in alcohol solutions has widespread industrial applications. This work presents studies on coalescence in aqueous solutions of pentanol, methyl isobutyl carbinol, hexanol, heptanol, and octanol. The effects of the alcohol concentration, hydrocarbon chain length, adsorption at the air–water interface, electrolyte, and intermolecular and surface forces on bubble coalescence were investigated. The origin of stability of the thin aqueous films was studied. The zeta potential at the air–water interface was measured in the presence of these alcohols and a 1:1 electrolyte. The charge at the interface decreased in the presence of alcohol. It was found that the electrostatic double layer force does not have any significant effect in the stability of these thin films. The major stabilization comes from the hydration force. In aqueous heptanol and octanol solutions, the hydrophobic force plays a vital role so that the stabilizing effect of these alcohols is partly incapacitated. The coalescenc...

The role of solvents in drug transport has not been properly addressed in the literature, despite its well known influence on drug permeation. Previously we have conducted thermodynamic and kinetic analyses to probe the molecular mechanisms of alcohol enhanced permeation. In the present study, the influence of temperature on the partitioning of methyl paraben into silicone membranes is investigated. In line with previous membrane transport studies of methyl paraben in silicone membranes, butanol and heptanol are used as representative alcohols. The results show higher amounts of methyl paraben extracted from the silicone membrane following equilibration with butanol, at all experimental temperatures. This was in line with alcohol uptake data. In fact, a linear correlation (r(2) ∼0.97) was found between the amount of methyl paraben in the silicone membrane and the corresponding alcohol uptake. Calculated "specific" vehicle-membrane partition coefficients for both alcohols were approximately one, suggesting that the effective concentrations of methyl paraben inside and outside the membrane were the same. Thermodynamic analysis of the alcohol-membrane partition coefficients as a function of temperature showed no apparent trend for butanol, with an associated enthalpy change of approximately zero. Conversely, there was a positive trend in the van't Hoff plot for methyl paraben in heptanol, indicative of an exothermic process. Moreover, the partitioning trends of methyl paraben in silicone membranes obtained from membrane transport and equilibrium experiments were not the same. This reflects the fundamental differences between the calculated vehicle-membrane partition coefficients in the two studies. Finally, the findings from membrane transport and equilibrium experiments support a model of alcohol enhanced permeation where high solvent sorption promotes high solute concentrations in the overall volume of the membrane (i.e. K), thus leading to modified solute transport (i.e. increased flux). The same model also accounts for changes in membrane diffusivity (i.e. D) related to the properties of the imbibed alcohol.

Electromembrane extraction (EME) and CE with capacitively coupled contactless conductivity detection (CE-C(4) D) was applied to rapid and sensitive determination of perchlorate in drinking water and environmental samples. Porous polypropylene hollow fiber impregnated with 1-heptanol acted as a supported liquid membrane (SLM) and perchlorate was transported and preconcentrated in the fiber lumen on application of electric field. High selectivity of perchlorate determination and its baseline separation from major inorganic anions was achieved in CE-C(4) D using background electrolyte solution consisting of 7.5 mM L-histidine and 40 mM acetic acid at pH 4.1. The analytical method showed excellent parameters in terms of reproducibility; RSD values for migration times and peak areas at a spiked concentration of 15 μg/L of perchlorate (US EPA recommended limit for drinking water) were below 0.2 and 8.7%, respectively, in all examined water samples. Linear calibration curves were obtained for perchlorate in the concentration range 1-100 μg/L (r(2) ≥0.999) with limits of detection at 1 μg/L for tap water and at 0.25-0.35 μg/L for environmental and bottled potable water samples. Recoveries at 15 μg/L of perchlorate were between 95.9 and 106.7% with minimum and maximum recovery values for snow and bottled potable water samples, respectively.

QRS widening and QT prolongation are associated with bupropion. The objectives were to elucidate its cardiac electrophysiological properties. Patch-clamp technique was used to assess the I(Kr) -, I(Ks) -, and I(Na) -blocking effects of bupropion. Langendorff retroperfusion technique on isolated guinea-pig hearts was used to evaluate the MAPD(90) -, MAP amplitude-, phase 0 dV/dt-, and ECG-modulating effects of bupropion and of two gap junction intercellular communication inhibitors: glycyrrhetinic acid and heptanol. To evaluate their effects on cardiac intercellular communication, fluorescence recovery after photobleaching (FRAP) technique was used. Bupropion is an I(Kr) blocker. IC(50) was estimated at 34 μm. In contrast, bupropion had hardly any effect on I(Ks) and I(Na) . Bupropion had no significant MAPD(90) -modulating effect. However, as glycyrrhetinic acid and heptanol, bupropion caused important reductions in MAP amplitude and phase 0 dV/dt. A modest but significant QRS-widening effect of bupropion was also observed. FRAP experiments confirmed that bupropion inhibits gap junctional intercellular communication. QT prolongation during bupropion overdosage is due to its I(Kr) -blocking effect. QRS widening with bupropion is not related to cardiac sodium channel block. Bupropion rather mimics the QRS-widening, MAP amplitude- and phase 0 dV/dt -reducing effect of glycyrrhetinic acid and heptanol. Unlike class I anti-arrhythmics, bupropion causes cardiac conduction disturbances by reducing cardiac intercellular coupling.

The enhancement of physical absorption of CO2 in the presence of second liquid phase (dispersed organic phase) was investigated due to many important industrial applications. Gas-liquid interfacial area, volumetric mass transfer coefficient and amplification factor were calculated and discussed using penetration model. The experimental results indicated that addition of the dispersed organic phase to water leads to the increase of volumetric mass transfer coefficient by 46%, 34%, 20% for heptanol, toluene and heptane respectively. The performed in this paper shows that addition of the dispersed organic phase to water increases gas-liquid interfacial area and reduces bubble diameter. These two effects play an essential role in the rate of carbon dioxide absorption increase. The effect of enhancement could be quantified by an amplification factor.

The conductivity (σ) measurement was carried out on water/dioctyl sulfosuccinate sodium salt (DOSS)/heptanol (decanol)/toluene reverse microemulsions. Addition of toluene was distinctly observed to inhibit the conductance percolation of water/DOSS/decanol/toluene systems. The effect of additives (sodium chloride, sodium salicylate and sodium cholate) with various concentrations on the conductivity behavior of water/DOSS/heptanol (decanol)/toluene systems was also investigated and discussed. The conductivity of a water/DOSS/heptanol/toluene system was almost unchanged in the concentration ranges of sodium chloride and sodium salicylate studied, while it decreased with the increase in the sodium cholate concentration. The conductance of the water/DOSS/decanol/toluene system increased with increasing of sodium cholate and sodium salicylate concentrations, and it changed little with the sodium chloride concentration. The lnσ value exhibited a linear correlation with temperature in the range of 5–40 °C. No percolation threshold induced by temperature was detected either in the absence or in the presence of additives. Furthermore, the activation energy for conductivity was estimated and discussed according to the Arrhenius type equation. The present study would provide useful information for selecting a suitable template for nanometer materials preparation.

Aim: To investigate mechanisms behind heptanol (Hp)-induced infarct size reduction and in particular if protection by pre-treatment with Hp is triggered through mitochondrial mechanisms. Methods: Langendorff perfused rat hearts, isolated mitochondria and isolated myocytes were used. Infarct size, mitochondrial respiration, time to mitochondrial permeability transition pore (MPTP) opening and AKT and glycogen synthase kinase 3 beta (GSK-3β) phosphorylation were examined. Results: Pre-treatment with Hp reduced infarct size from 29.7 ± 3.4% to 12.6 ± 2.1%. Mitochondrial potassium channel blockers 5-hydroxy decanoic acid (5HD) blocking mitoKATP and paxilline (PAX) blocking mitoKCa abolished cardioprotective effect of Hp (Hp + 5HD 36.7 ± 2.9% and Hp + PAX 40.2 ± 2.8%). Hp significantly reduced respiratory control ratio in both subsarcolemmal and interfibrillar mitochondria in a dose-dependent manner (0.5–5.0 mm). The ADP oxygen ratio was also significantly reduced by Hp (2 mm). Laser scanning confocal microscopy of tetramethylrhodamine-loaded isolated rat myocytes using line scan mode showed that Hp increased time to MPTP opening. Western blot analysis showed that pre-treatment with Hp increased phosphorylation of AKT and GSK-3β before ischaemia and after 30 min of global ischaemia. Conclusion: Pre-treatment with Hp protects the heart against ischaemia-reperfusion injury. This protection is most likely mediated via mitochondrial mechanisms which initiate a signalling cascade that converges on inhibition of opening of MPTP.

TiO2-ZrO2 was prepared with surfactant through a sol-gel method. Catalysts containing 5 - 35% H3PO4 were prepared using these oxides. Subsequently the catalytic performance of prepared catalysts was determined for liquid phase esterification of aromatic acids. H3PO4/TiO2-ZrO2 has been used as catalyst to synthesize various novel esters by esterification of some aromatic acids with aliphatic alcohols (2-propanol, 1-butanol, iso butanol, 3-pentanol, 1-hexanol, heptanol, cyclo heptanol, octanol and decanol). Under optimized conditions, maximum yields and selectivity (100%) to the corresponding ester, was obtained by using 25 wt % H3PO4/TiO2-ZrO2 as catalyst. The Catalyst can be easily recycled after reaction and can be reused without any significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present synthetic protocol. The reaction was carried out under solvent-free condition.

Densities and speeds of sound for binary mixtures of 1,2-ethanediol with three alkanols (2-ethyl-1-hexanol, 1-heptanol, or ethanol) were measured over the entire composition range in the temperature 298.15 K by means of a vibrating-tube densimeter and pulse-echo-overlap method. Density measurements were also made for mixtures of 1,2-ethanediol with 1-nonanol at the temperatures (293.15 and 298.15) K. From these data, the excess molar volumes and excess molar isentropic compressibilities as well as the deviations of speed of sound were calculated and approximated by the Redlich−Kister polynomials. The negative values of the excess molar volumes and isentropic compressibilities over the entire composition range are observed only in the case of ethanol. In the cases of 2-ethyl-1-hexanol, 1-heptanol, and 1-nonanol, the positive values of the excess molar volumes over the entire composition range are observed. Simultaneously, the negative values of the excess molar isentropic compressibilities over the entire ...

Alcohol will be an exceptional alternative fuel for existing diesel engines because of its built-in fuel-improving properties (high cetane number and high energy content). Biosynthesis of N-heptanol by means of engineered microbes, such as the Clostridium species and Escherichia coli, is an active area of research. Hence, extensive investigation on the compatibility of N-heptanol in existing diesel engines is necessary. This study examined the effect of heptanol mustard oil biodiesel blends of varying proportions on the emission and performance patterns in a 1,800 r/min constant-speed immobile diesel engine. The main objective of this investigation was to investigate the reduction in all the emissions and increase the performance characteristics associated with neat mustard oil biodiesel when deploying three different fuels. Base catalyzed transesterification process was employed to convert the mustard oil into mustard oil biodiesel. Heptanol with 98.4 % purity was used as an oxygenated additive. The experimental results revealed that converting heptanol to mustard oil biodiesel caused a significant reduction in hydrocarbons, carbon monoxide, nitrogen oxides, and smoke emissions when compared to mustard oil biodiesel in naturally aspirated conditions.

Densities and viscosities for 1,2-propanediol + 1-heptanol or 1-hexanol and 1,2-ethanediol + 2-butanol or 2-propanol were measured over the whole composition range at (298.15, 303.15, and 308.15) K and at atmospheric pressure. From the experimental data, the excess molar volume, VmE, partial molar volumes, Vm,1 and Vm,2, and excess partial molar volumes, Vm,1E and Vm,2E, over the entire range of composition were calculated. Viscosity deviations, Δη, were also obtained and showed negative values for all investigated systems. These results were fitted to the Redlich−Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of McAllister, and calculated functions have been used to explain the intermolecular interaction between the mixing components.

A novel fluorine-containing copolymer surfactant was synthesized via free radical copolymerization from maleic anhydride and rapeseed oil firstly, and then followed by an esterification reaction with dodecafluoro heptanol. The reaction progresses were monitored on-line by FTIR and the copolymerization was characterized by molecular weight (GPC) analysis. Simultaneously, the surface tension and critical micelle concentration (CMC) together with the biodegradability of the fluorine-containing copolymer surfactant were investigated in detail. The results indicate that this fluorine-containing surfactant with Mw of 66000 g/ mol and Mn of 38800 g/mol shows a strong surface tension lowering ability, the CMC is 0.1 g/L, the surface tension value at the CMC (γCMC) is 22.5 mN m−1 and less than the corresponding copolymeric hydrocarbon surfactant; the evaluation of biodegradability indicates that the biological respiration curve of the fluorine-containing copolymer surfactant with concentration of 1000 mg/L is above the endogenous respiration curve; the BOD5/COD value is higher than 0.45; the COD and TOC removal ratios after 5 days of biodegradation reach 91.0 and 89.4%, respectively, showing good biodegradability and environmental-friendly feature.