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The influence of alcohols with different alkyl chain length (methanol, ethanol and propanol) on the physicochemical properties (turbidity, surface hydrophobicity, exposed and total free sulfhydryl groups, denaturation temperature; Tm) of pasteurized liquid egg white (PLEW), including gel properties (gel hardness and expressible liquid) and microstructure of heat-induced PLEW gel prepared at 75°C were studied. The results showed that alkyl chain length of alcohol and alcohol concentration had no impact on the total free sulfhydryl groups, but significantly increased the turbidity, surface hydrophobicity, exposed free sulfhydryl groups, gel hardness and expressible water. Increase the alkyl chain length of alcohol also significantly decreased the Tm and the total enthalpy change during heat-induced gelation of PLEW. Addition of 5% alcohol altered the microstructure of the PLEW gels in an alkyl chain length dependent manner.

The Schiff base ligand L, which was derived from 2-hydroxy naphthaldehyde and benzidine characterized by various spectral techniques like FT-IR, 1H NMR and Mass. The ligand (L) which was soluble in the various solvents like acetonitrile, dimethyl sulfoxide, dichloromethane, dimethylformamide, ethanol, methanol, propanol, THF and toluene. The UV-visible absorption and emission spectral behaviour has been studied. The binding nature of L with various anions was carried out by the addition of L with tert-butyl ammonium salts of F−, Cl−, Br−, I−, NO3–, SCN− and ClO4− ion in THF medium and among all of anions L has more binding behaviour with F− ion. The binding nature of L with anions was monitored by UV-visible absorption and fluorescence emission spectroscopy.

In the present exertion, effect of Ethylhexyl Nitrate inclusion to Diesel-Waste Plastic oil-Propanol mixture were found with regard to Performance as well as Exhaust emission like NOx, CO, and CO2 in a Compression Ignition engine. Initially, Propanol-Diesel-WPO mixture indicated as P10 are primed with blending 10% of Propanol with 80% of Diesel and 10% of WPO fuel as fraction. The remaining mixtures represented as P10EHN2 (10% Propanol, 2% EHN, 10% WPO and 78% Diesel), P10EHN4 (10% Propanol, 4% EHN,10% WPO and 76% Diesel) and P10EHN6 (10% Propanol, 6% EHN 10% WPO and 74% Diesel) were prepared by blending Propanol-Diesel-WPO-EHN for getting data concerning the performance of EHN. The output got on behalf of all mixtures at various loads were related with P10 and pure Diesel. It was established that EHN inclusion increased the Cetane value by 4%, 10%, 15% for P10EHN2, P10EHN4 and P10EHN6 related with P10 while EHN influenced a minor reduction in Kinematic Viscosity, Calorific value and a small raise in solidity. From the research it is concluded that EHN inclusion has a dropping impact on NOx, CO output and Brake Power, on the other hand it has growing impact on CO2 output and Brake Specific Fuel Consumption.

Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature 303.15K. From the experimental densities, viscosities and sound velocity, the excess molar volume (VE), deviation in viscosity (Δη) and deviation in isentropic compressibility (ΔKS) have been calculated. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures.

Based on the analysis of dynamic properties of ionic liquid solutions, the descriptions of diffusion mechanisms are built for dimethylimidazolium chloride (dmim+/Cl−)–alcohol solute systems and the influence of the monohydric alcohols' molecular structure on their diffusion mechanisms in dmim+/Cl−–alcohol at T = 400 K by molecular dynamics simulations are studied. From the analysis of radial distribution functions, MSDs, velocity autocorrelation function, and autocorrelation functions of dispersion we found that the motion of all components in IL dmim+/Cl−–alcohol (ethanol, propanol) systems at T = 400 K occurs in the sub-diffuse regime and that the dynamics of the dmim+/Cl−–alcohol (ethanol, propanol) systems is heterogeneous. The increase of the alkyl chain length of the alcohol molecule does not affect the motion of the ionic liquid components; instead, it increases the characteristic times describing the model representation of alcohol molecule diffusion at short and medium times, without affecting diffusion mechanisms.

A convenient manganese catalyzed transfer hydrogenation of N-heteroarenes by using alcohols as hydrogen sources is presented. Ideal results are achieved by applying the 6-methyl substituted triazine based PiprN5Pipr manganese pincer complex Mn-1, which allows the hydrogenation of various substituted N-heteroarenes in good to excellent isolated yields. More importantly, biomass derived ethanol could be realized in this transformation as well, thus highlighting the sustainability of the process. Detailed DFT calculation studies support an outer sphere hydrogenation mechanism and hydride transfer from propan-2-olate to the Mn center with regeneration of the catalyst as the rate-determining step.

The solubilities of oleanolic acid and ursolic acid in 1-butanol, methyl isobutyl ketone, methyl tert-butyl ether, and 2-propanol + water binary solvent systems at different temperatures were deter...

The present work provides thermophysical data on binary mixtures of titanium(IV) isopropoxide (TTIP) and 2-propanol (iPOH), which are important precursor solutions in spray flame synthesis of nanoparticles. The specific density, viscosity, thermal conductivity, and molar isobaric heat capacity were measured at 101.3 kPa and temperatures ranging from 293.15 to 333.15 K. The vapor–liquid equilibrium (VLE) was measured at pressures ranging from 20 to 80 kPa. Furthermore, self-diffusion coefficients of pure iPOH were measured at 101.3 kPa and temperatures ranging from 293.15 to 333.15 K. A qualitative study using 1H NMR spectroscopy provides evidence for a cross-association between TTIP and iPOH in the mixture. Correlations for all studied thermophysical properties are provided. The results establish a rational basis for the design of spray flame synthesis processes.

Self-assembly of surfactant systems in organic solvent–water mixed media is relevant in several industrial and pharmaceutical applications. This article emphasizes the role of 2-propanol (PrOH) as ...

EVALUATION OF THE CEREBROPROTECTIVE ACTION OF 1-ADAMANTY- LOXY-3-MORPHOLINO-2-PROPANOL HYDROCHLORIDE IN RATS WITH EXPERIMENTAL HEMORRHAGIC STROKE ACCORDING TO THE DYNAMICS OF NEUROCYTOLYSIS, NEUROAPOPTOSIS AND NEUROPROLIFERATION MARKERS

Microkinetic models based on first principles calculations have been used to study the vapor and liquid phase hydrodeoxygenation of propionic acid on a Rh(1 1 1) surface. Calculations suggest that both decarboxylation and decarbonylation do not occur at an appreciable rate under all reaction environments. Propanol and propionaldehyde are the main products on this surface and they are produced at similar rates in both vapor and liquid phase environments. While a condensed phase can shift the reaction rate, the dominant pathways and selectivity towards the various products are hardly affected. At 473 K, the turnover frequency is increased by about a factor of 1.5 in liquid water relative to the gas phase. In liquid 1,4-dioxane, the turnover frequency is also slightly increased relative to the gas phase. Given the uncertainty in Rh cavity radius in the liquid phase calculations, computations with different cavity radii have been performed. With larger Rh cavity radius, the promotional effect of the solvents on the turnover frequency becomes more significant, while practically no changes are observed for a smaller cavity radius.

Ionic cross-linking of polyurethane (PU) was performed using grafted glutaric acid (GA) or dimethylamino propanol (DAP) to enhance the mechanical properties and control the degree of interaction using acid or base. The effect of ionic cross-linking on the water compatibility, thermal phase transition of soft segments, tensile mechanical strength, and shape memory properties were determined by comparison with ordinary PU. The water compatibility of PU could be improved by grafted acidic or basic functional groups. The breaking tensile stress and shape recovery capability increased significantly relative to ordinary PU due to ionic cross-linking but notably decreased upon the addition of acid or base due to the disruption of ionic cross-linking. It was demonstrated that the water compatibility and mechanical properties of PU could be controlled using ionic cross-linking and the disruption of ionic cross-linking by adding acid or base.

In the current work, nomal ZnO and Au textured ZnO based quantum dot (QD) thin film sensors have been fabricated and characterized. The uniqueness of the present sensor is its operating temperature of 35°C and can be employed to detect minute fraction of organic compound gases like: methanol, ethanol, propanol, butanol etc with better response and improved repeatability/stability at (little elevated) room temperature. Sol-gel growths along with spin coating methods have been used in the fabrication of the proposed sensor. To improve the response of the sensors annealing treatment at 350°C temperature is imposed. Different material characteristics like, TEM, XRD, AFM, UV spectroscopy, FTIR and electrical characteristics have been reported for better understanding the morphology, molecular compositions and mechanism of the fabricated sensors.

In this paper, biofiltration of a mixture of propane and toluene in a biofilter packed with a compost—woodchip mixture has been considered. The purpose of this article is based on solving the nonlinear toluene and propanol equations of the biofilm problem by the Adomian decomposition method (ADM). The conclusion of the numerical and analytical results of the concentration of the propanol and toluene are not only to an accuracy of them it is an understanding their procedure for solving process. The error percentage between Adomian decomposition method (ADM) and numerical results is observed. Furthermore, the reported analytical result is useful in future modification of mathematical modeling of the biofilter.

The isobaric vapor–liquid equilibrium (VLE) data of 1-methoxy-2-propanol (PM) + 1,2-propanediol (PG) and 2-methoxy-1-propanol (MP) + 1,2-propanediol (PG) was measured in this work by a modified Ros...

Micro–nanoscale surface microstructure of electrodeposited nickel on AISI 430 substrate from sulfamate bath with ionic and nonionic additives was investigated. 0.69 × 10−4-2.08 × 10−4 M sodium dodecyl sulfate (SDS) and 0.5-4.0 M sodium chloride (NaCl) were used as ionic additives. 0.5-4.0 M ethanol and 1-propanol were used as nonionic additives. Ethanol, propanol, and NaCl promote evolution of nickel micro–nanocones/pyramids. Concentration of these additives, especially NaCl, plays a significant role to modify nickel microstructure. Adhesion of deposited nickel with the substrate, determined by crosscut tape test, is excellent for SDS, ethanol, and propanol additive regardless of their concentration. NaCl degrades the adhesion resulting 100% removal of deposited nickel for 4.0M additive in sulfamate bath. Nickel coating without additive and 1.39 × 10−4 M SDS additive corrode at the same rate (1.08 × 10−2 mm/year), while the other additives increase the corrosion rate.

Flux balance analysis (FBA) has been widely used for detecting internal fluxes of bacteria. In this study, FBA was applied to estimate metabolic phenotype in glucose fermentation under negative pressure. Result revealed that ethanol, propionic acid, and butyric acid were converted to acetate by lowering headspace pressure (HP) of fermenter with the conversion rate of 0.091, 0.014, and 0.017 mol-acetate/mol-glucose respectively In addition, these three substances were simultaneously converted into H2 with the conversion rate of 0.258 mol-H2/mol-glucose. A total of 30% acetate and 26% H2 production increase were observed under condition of 0.6 atm HP fermentation. Furthermore, 30% accumulated hydrogen was consumed in the formation of propanol and valeric acid.

The single-crystal structures of three salts of bedaquiline, a drug used for the treatment of drug-resistant tuberculosis (TB), are described., Bedaquiline [systematic name: 1-(6-bromo-2-meth­oxy­quinolin-3-yl)-4-(di­methyl­amino)-2-(naphthalen-1-yl)-1-phenyl­butan-2-ol, C32H31BrN2O2] is one of two important new drugs for the treatment of drug-resistant tuberculosis (TB). It is marketed in the US as its fumarate salt {systematic name: [4-(6-bromo-2-meth­oxy­quinolin-3-yl)-3-hy­droxy-3-(naphthalen-1-yl)-4-phenyl­but­yl]di­methyl­aza­nium 3-carb­oxy­prop-2-enoate, C32H32BrN2O2 +·C4H3O4 −}, and about a dozen other salts of bedaquiline have been described in patent literature, but none have so far been structurally described. In a first communication, we present the crystal structure of bedaquilinium fumarate and of two new benzoate salts, as well as that of a degradation product of the reaction of bedaquilinium fumarate with sodium ethoxide, 3-benzyl-6-bromo-2-meth­oxy­quinoline, C17H14BrNO. The fumarate and benzoate salts both feature cations monoprotonated at the di­methyl­amino group. The much less basic quinoline N atom remains unprotonated. Both salts feature a 1:1 cation-to-anion ratio, with the fumarate being present as monoanionic hydro­fumarate. The conformations of the cations are com­pared to that of free base bedaquiline and with each other. The flexible backbone of the bedaquiline structure leads to a landscape of conformations with little commonalities between the bedaquiline entities in the various structures. The conformations are distinctively different for the two independent mol­ecules of the free base, the two independent mol­ecules of the hydro­fumarate salt, and the one unique cation of the benzoate salt. Packing of the salts is dominated by hydrogen bonding. Hydrogen-bonding motifs, as well as the larger hydrogen-bonded entities within the salts, are quite similar for the salts, despite the vastly differing conformations of the cations, and both the hydro­fumarate and the benzoate structure feature chains of hydrogen-bonded anions that are surrounded by and hydrogen bonded to the larger bedaquilinium cations, leading to infinite broad ribbons of anions, cations, and (for the benzoate salt) water mol­ecules. The benzoate salt was isolated in two forms: as a 1.17-hydrate (C32H32BrN2O2 +·C7H5O2 −·1.166H2O), obtained from acetone or propanol solution, with one fully occupied water mol­ecule tightly integrated into the hydrogen-bonding network of anions and cations, and one partially occupied water mol­ecule [refined occupancy 16.6 (7)%], only loosely hydrogen bonded to the quinoline N atom. The second form is an aceto­nitrile solvate (C32H32BrN2O2 +·C7H5O2 −·0.742CH3CN·H2O), in which the partially occupied water mol­ecule is replaced by a 74.2 (7)%-occupied aceto­nitrile mol­ecule. The partial occupancy induces disorder for the benzoate phenyl ring. The aceto­nitrile solvate is unstable in atmosphere and converts into a form not distinguishable by powder XRD from the 1.17-hydrate.

This paper reports the newly measured experimental data for CO2 solubility in a blended aqueous solution of monoethanolamine (MEA) and 2-amino-2-methyl-propanol (AMP) at different amine mixing ratios (MEA/AMP/H2O = 9:21:70, 15:15:70, and 21:9:70 wt %) and working temperatures (323.15, 373.15, and 383.15 K). The successive substitution method was used for calculating the mole fractions of all molecules (four molecules) and electrolytes (three cations and four anions) from the equilibrium along with the material and charge balance equations (11 equations). The electrolyte nonrandom two-liquid (e-NRTL) model was used to investigate nonideality in the liquid phase. Using the abovementioned thermodynamic models, the partial pressures of CO2 in the gas phase, mole fractions of all components in the liquid phase, pH variations, heats of absorption, and cyclic capacities of CO2 according to the absorption/desorption temperature and the blending ratio of MEA/AMP were estimated.

A series of mixed Al2O3-Ga2O3 oxides were prepared with different Ga2O3 content (labeled as AlGa-x; where x is the wt % of Ga2O3) by precipitation method. The oxides were then used as supports of palladium (2 wt %) catalysts (labeled as Pd/AlGa-x). Both series of samples, AlGa-x and Pd/AlGa-x were characterized by several techniques such as Raman spectroscopy, XPS, XRD, SEM, and HRTEM, and were tested in the 2-propanol dehydration reaction. The steady-state conversions displayed by the Pd/AlGa-x series was almost twice as that obtained for the AlGa-x series in all the range of tested temperatures. It was worth noting that the presence of palladium changed the yield observed for the AlGa-x series mainly at low temperatures. While at high temperatures the Lewis acidity provided by the well dispersed Pd nanoparticles increased the activity considerably and improved the propylene production. A balance between the dispersion of palladium and the surface acidity, both related to the Ga2O3 content was responsible for the observed catalytic behavior.

The present study aimed to analyze reaction kinetics and mechanism for the synthesis of propyl benzoate in solvent-free conditions. Lipase was immobilized on Hydroxypropyl methylcellulose (HPMC) and polyvinyl alcohol (PVA) polymer blend by entrapment method. Among different lipases immobilized on a support, Candida cylindracea (CCL) showed excellent activity. Systematic studies were done to optimize the reaction conditions. The activation energy was found to be 16.2 kcal/mol for immobilized CCL. Kinetic parameters were calculated, which depicted that propyl benzoate synthesized using immobilized CCL followed the ternary complex model in which propanol inhibits lipase activity at higher concentrations. Recyclability of the catalyst was checked up to four catalytic cycles and 40% retention of activity was observed up to the fourth cycle. Finally, the applicability of developed protocol to synthesize various alkyl benzoates was explored.

A primary anti-coagulant narrow therapeutic index warfarin sodium poses a high risk of thrombosis or excessive bleeding with a sudden death. The root cause for these risks are not well established....

Potassium and antimony mixed oxides were obtained by calcination of the commercial potassium-antimony tartrate trihydrate K(SbO)C4H4O6.3H2O at temperatures ranging from 300 to 800 °C. The structure varied with temperature as revealed by XRD characterization. The modifications occurring during the calcination process were also studied by FT-IR and DRS spectroscopies, along with by thermal analysis (TG/DTG). The solids were tested in 2-propanol decomposition at 200 °C, used as probe reaction for the investigation of acid-basic and redox properties. The catalytic activity was function of the calcination temperature and the best 2-propanol conversion was achieved with the tartrate precursor calcined at 500 °C that crystallizes forming KSbO3 as main phase along with K0.51Sb2.67O6.26 as secondary phase. Under N2 the activity reached the maximum after 10 min, 80% of 2-propanol conversion was the highest value, over the sample calcined at 500 °C, but rapidly decreased with time on stream and almost declined after 1 h. In the presence of air in the reaction mixture, 85% of 2-propanol conversion was achieved at 200 °C, after 20 min under stream, with the most active sample. By increasing the calcination temperature above 500 °C, the conversion decreased, especially for the sample calcined at 800 °C showing the worse conversion, although the stability over time increased, likely due to the achievement of stable crystalline phases and crystallite sizes. In all cases, the 2-propanone selectivity was close to 100%. This behaviour confirmed the occurrence of a dehydrogenation reaction involving the basic sites typical of KSbxOy oxides along with the redox couple Sb(V)/Sb(III).

Seven racemic 5,7-dimethoxyflavanones afforded conglomerate crystals upon recrystallization from a solvent. Three methodologies were investigated to achieve asymmetric transformation based on dynamic crystallization of the chiral conglomerate system. The first was chiral symmetry breaking of racemic flavanones by attrition-enhanced deracemization. Continuous suspension of racemic flavanones in a small amount of propanol in the presence of a base (1,8-diazabicyclo[5.4.0]­undec-7-ene (DBU)) and glass beads promoted chiral symmetry breaking and converted the flavanones to crystals of (+)- or (−)-enantiomers with 78 to 99% ee. The second method involved cyclization of the intermediate aldol product to give optically active flavanone with 90% ee involving a reversible oxa-Michael addition reaction with attrition-enhanced deracemization. The third was a reaction starting from prochiral 2-hydroxy-4,6-dimethoxyacetophenone and 2-naphthaldehyde under basic conditions, which gave the corresponding flavanone in 89% ee.

In this work an experimental and kinetic modeling study on n-propanol and i-propanol combustion has been performed. New burning velocity measurements were carried out using the heat flux method at 1 atm over the temperature range of 323–393 K. Analysis of the temperature dependence was conducted with to verify the data consistency of the new and available data from the literature. Important inconsistencies were identified with the literature experiments performed using the spherical flame method and the nature of such inconsistencies was discussed. Moreover, a new kinetic mechanism, based on the most recent Konnov model and extended to include C3 alcohol isomers chemistry subset, was validated against new and all available literature data obtained at different combustion regimes. Rate constant parameters were carefully selected by evaluating all experimental and theoretical sources. Moreover, Sarathy et al. (2014) detailed kinetic mechanism was also tested. Overall, both kinetic models reproduce experimental data with good fidelity, but the presented model was found superior in representing ignition delay times data performed at high-pressure conditions.

The solubility data of sorbic acid in binary systems of (ethanol + water), (1-propanol + water) and (2-propanol + water) were measured from 283.15 to 323.15 K using the static equilibrium method under atmospheric pressure. It was found that the solubility of sorbic acid in the three binary solvent systems increased with increasing temperature as well as increasing initial mole fraction of organic solvent in these systems. The van’t Hoff–Jouyban–Acree model, the modified Apelblat–Jouyban–Acree model and the CNIBS/R-K model were proposed for correlating the experimental solubility values in various solution systems. Furthermore, the dissolution thermodynamic properties of Gibbs energy change (ΔsolGo), molar enthalpy change (ΔsolHo) and molar entropy change (ΔsolSo) were calculated from the experimental solubility data, using the van’t Hoff equation. The positive values of ΔsolGo, ΔsolHo and ΔsolSo indicate that these dissolution processes of sorbic acid in the solvents studied were all endothermic and entropically favorable. In addition, the change of dissolution enthalpy was the main contributor to the positive value of the molar Gibbs energy of the dissolution process. The experimental solubility and the models used in this work would be conducive to purifying sorbic acid from its crude mixtures.

Experimental study on combustion characteristics and method for evaluating flame stability was carried out. Methyl palmitate, ethyl palmitate, propyl palmitate, butyl palmitate, and amyl palmitate were prepared using pyridine n-butyl bisulfate ionic liquid as catalyst in a self-designed reactor to catalyze esterification reaction of palmitic acid with methanol, ethanol, propanol, butanol, and pentanol, respectively. Combustion characteristics including the flame height, flame front area, and flame speed were analyzed; and OH-PLIF time-average total signal strength by the OH-PLIF technique and cold flow properties of linear-chain alkyl esters of palmitic acid were also studied. Image diagnosis was applied to the study of flame stability, and an image segmentation method using three color feature matrices of flame corresponding to the red, green, and blue components was proposed. A color was selected as the evaluation color and the iterative method was used to obtain the optimal threshold for the area where the flame was located. Each pixel in the matrix was compared with an optimal threshold, and the flame stability was evaluated by calculating the ratio variance under continuous conditions. The method is simple in operation, accurate in repeatability, less interfered, and provides some guidance for analysis and optimization of biodiesel combustion process.

Density functional theory (DFT) method was carried out to investigate the molecular interaction between metalloporphyrin-based sensor and propanol. The relative energies were used to determine the ...

Synthesis of lactulose with crosslinked aggregates of Bacillus circulans β-galactosidase (CLAGs) has been compared in batch and repeated-batch operation for the first time. The effect of the type of the precipitating agent and its concentration, the crosslinker concentration and the time of crosslinking were evaluated for their effect on the parameters: immobilization yield, specific activity and thermal stability of the biocatalysts. The type and concentration of the precipitating agent were the variables that produced a significant variation in the immobilization parameters of the biocatalyst. CLAGs were obtained with a specific activity of 7790 IUH⋅g−1 at an immobilization yield of 46.2 % using 50 % v/v of propanol as precipitating agent, 5.5 gglutarldehyde gprotein−1 for crosslinking and 1 h of crosslinking time. This biocatalyst was more stable than the free enzyme with a stabilization factor of 11.3 h at 50 °C. Highest yield of lactulose synthesis with CLAGs was 0.42 g g−1 for a fructose/lactose molar ratio of 8. Repeated-batch operation allowed a significant increase in lactulose production per unit mass of biocatalyst and in cumulative productivity with respect to batch operation, yielding an efficiency of biocatalyst use of 2.43 kglactulose gbiocatalyst protein−1.

Herein environment-friendly solvent 2-propanol-water (95:5 v/v) acidified with 0.5 M oxalic acid was utilized to extract gossypol, a naturally occurring pigment of cottonseed. This polyphenolic pigment gossypol acts as a toxin to cottonseed oil and protein during processing of cottonseed by imparting a dark colouration. The parameters affecting the solvent extraction process, such as temperature, solvent-to-seed ratio, acid concentration and contact time, were studied and optimized along with evaluation of kinetic and thermodynamic parameters. The gossypol extraction followed pseudo-second-order kinetics and the kinetics mechanism displayed the diffusion of gossypol from solid phase to the liquid phase. The extraction process was internal diffusion controlled, and internal solid diffusion was the rate controlling step. The optimum conditions for extraction of gossypol were obtained experimentally as 0.5 M oxalic acid concentration, temperature of 348 K, solvent-to-seed ratio of 15 and an extraction time of 180 min, exhibiting maximum gossypol extraction of 95.43% under these conditions. The activation energy of extraction was found out to be 6.099 kJ/mol while the gossypol extraction process was found out to be endothermic in nature, viable and increased the degree of randomness of extraction process. 2-Propanol-water solvent proved to be a potent green solvent for extraction of gossypol from cottonseed.

We report the synthesis of xCuO/TiO2-ZrO2 catalysts containing 1, 5 and 10 wt % CuO by the sol-gel method. The solids were dried at 100 °C for 24 h and calcined at 400 °C for another 24 h in an open-air atmosphere. Part of these samples was impregnated with 0.5 wt % of PtO by the wet impregnation method. Samples were characterized by H2-TPR, TPD-CO2, SEM, TEM, XRD and 2-propanol decomposition. Our H2-TPR results indicate that Pt impregnation on the xCuO/TiO2-ZrO2 system promotes the CuO reduction at lower temperature close to 190 °C. UV–Vis bands were associated with isolated Cu2+ ions in octahedral coordination corresponding to CuO particles; and isolated Cu2+ ions in coordination lower than octahedral. Pt impregnation on the surface of the xCTZ samples promotes new basic sites appearing at high temperature as confirmed by TPD-CO2. The higher conversion for the decomposition of 2-propanol to acetone shows that the basic properties of the CuOxPtOx/TiO2-ZrO2 catalysts are superior to those of CuOx/TiO2-ZrO2 samples.

Platinum–rhodium nanoparticles modified with cesium salt of phosphotungstic acid, CsPTA, have been tested for electro-oxidation of 2-propanol in acidic medium. The resulting Pt-based nanoparticle-containing materials have been carried out using X-ray diffraction (XRD), microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and different electrochemical techniques combining with differential electrochemical mass spectrometry (DEMS). The experimental results such as cyclic voltammetry and chronoamperometry exhibit that films on carbon electrodes composed of CsPTA-modified PtRh/Vulcan nanoparticles improve the catalytic activity, in terms of potential and current densities recorded during electro-oxidation of 2-propanol, relative to the CsPTA-free PtRh/Vulcan nanoparticles. Particularly, the boost in the catalytic current densities is observed at low potential value (below 0.25 V vs. RHE). The differential electrochemical mass spectrometry measurements were utilized to recognize the reaction intermediates as well as products created during the electro-oxidation of 2-propanol. The results indicate that contributions from a straightforward oxidation of 2-propanol to CO2 are small in comparison to acetone yield.

Isobaric vapor–liquid equilibria (VLE) at 50.0, 101.3, and 200.0 kPa, have been measured for the binary system methyl nonafluorobutyl ether (x1) HFE-7100 + (1 – x1) 2-propanol. Thermodynamic consis...

The article is devoted to the analysis of the reaction kinetics of hydrogenation of 4-nitro-2'-hydroxy-5'-methylazobenzene in an aqueous solution of 2-propanol with acetic acid addition on skeletal nickel at different initial quantity of the starting compound. Clarification of the sequence of transformations of compounds containing several reactive groups, and the development of approaches to controlling the selectivity of processes with their participation is a practically significant task. According to the data obtained, at both low and high initial concentrations the hydrogenation of 4-nitro-2'-hydroxy-5'-methylazobenzene on skeletal nickel in a 2-propanol aqueous solution-0.01 M CH3COOH solvent proceeds in two parallel directions. The largest contribution in the first phase of the reaction is made by the azo group conversion of the starting compound, in contrast to the reaction in an aqueous solution of 2-propanol without acid addition. An increase in the initial quantity of the hydrogenated compound above its solubility limit leads to an increase in the rate of conversion of the azo group in 4-nitro- and 2-amino-2'-hydroxy-5'-methylazobenzene. Consequently, optimum quantity of 4-nitroaniline and 2-amino-2'-hydroxy-5'-methylazobenzene in the bulk solution during hydrogenation of the specified quantity of 4-nitro-2'-hydroxy-5'-methylazobenzene practically didn’t change, in contradiction to the hydrogenation on skeletal nickel in a neutral aqueous solution of 2-propanol. In a neutral aqueous solution of 2-propanol, when passing to high concentrations of the hydrogenated compound, the maximum yield of 4-nitroaniline increases twice as long the better, while as 4-amino-2'-hydroxy-5'-methylazobenzene, is reduced conversely. The results obtained do not contradict the concept of a parallel-sequential scheme for the conversion of 4-nitro-2'-hydroxy-5'-methylazobenzene. One of the directions involves the conversion of 4-nitro-2'-hydroxy-5'-methylazobenzene through 4-nitroaniline and 2-amino-4-methylphenol due to the hydrogenation of the azo group, and the second is the conversion of 4-nitro-2'-hydroxy-5'- methylazobenzene via 4-amino-2'-hydroxy-5'-methylazobenzene by reduction of the nitro group. At the end of the reaction, all the intermediate compounds are reduced to 2-amino-4-methylphenol and 1,4-phenylenediamine. When acetic acid is introduced into the composition of the neutral solvent 2-propanol-water, the contribution of the direction that ensures the formation of 4-nitroaniline and 2-amino-4-methylphenol to the overall reaction rate increases. An increase in the initial amount of 4-nitro-2′-hydroxy-5′-methyl-azobenzene leads to an increase in the rate of conversion of the azo group in the starting compound and to a decrease in the rate of conversion of 4-amino-2′-hydroxy-5′-methylazobenzene. The effect of the acid on the change in the conversion rates of nitro and azo groups to 4-nitro-2′-hydroxy-5′-methylazobenzene does not contradict the previously obtained results for the hydrogenation of its analogue, 2-nitro-2′-hydroxy-5-methylazobenzene, as well as individual compounds containing a nitro and azo group.

In this work, a new crystallization method was used to prepare two polymorphs of sulfamethazine–saccharin (SMT–SAC) cocrystal in bulk. The purity and crystal form of both polymorphs were confirmed by optical microscopy, scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. Moreover, the solubility of the stable form (form II) was determined by gravimetric analysis in nine pure solvents and one binary (acetonitrile + 2-propanol) solvent at temperatures ranging from 278.15 to 348.15 K at atmospheric pressure. Experimental data were correlated using the modified Apelblat model, the λh equation, the nonrandom two-liquid (NRTL) model, the Jouyban–Acree model, and the CNIBS/Redlich–Kister model. Finally, the apparent thermodynamic properties, such as $$\Delta_{\text{dis}} G$$, ΔdisH, and ΔdisS, were calculated on the basis of the activity coefficient obtained by the NRTL model. All the models correlate well, and all the experimental and calculated results indicate that the dissolution behavior of SMT–SAC cocrystal form II is a spontaneous, endothermic, and entropy-driven process.

Purpose: To develop a sensitive and accurate ultra-performance liquid chromatography–tandem mass spectrometric (UPLC-MS) method for quantification of ramipril in human plasma.Methods: Ramipril was extracted from biological fluid using equal volumes of n-hexane and propanol (1:1, v/v), and then chromatographed in a suitable C18 column with methanol: 0.1 % HCOOH (4: 1, v/v) as mobile phase. Atorvastatin was used as an internal standard for the chromatographic separation and quantification. The method was validated according to the United States Food and Drug Administration guidelines for standard indices.Results: Ramipril was determined in the concentration range 0.05 and 1000 ng/mL the validation procedure exhibited a correlation coefficient of 0.9979 + 0.002 (p = 0.05). The studied drug was quantified with lower ceiling of 0.05 ng/mL, and showed an accuracy of 105.00 %.Conclusion: A sensitive UPLC-MS analytical method has been successfully developed for the quantification of ramipril in human plasma. This method can be applied efficiently for the quantification of ramipril in bioavailability and pharmacokinetic studies. Keywords: Liquid chromatography–tandem mass, Ramipril, Stability, Biological fluids, Plasma

Elucidation of the substituted nitrobenzenes transformations sequence, in particular, containing several reactive groups and the development of approaches to the control of the selectivity of processes involving them is of interest from both theoretical and practical points of view. The article is devoted to the analysis of the hydrogenation kinetics of 2-nitro-2'-hydroxy-5'-methylazobenzene, 4-nitro-2'-hydroxy-5'-methyl-isobenzene, 4-nitroaniline, 4-amino-2'-hydroxy-5'-methylazobenzene on skeletal nickel in 2-propanol aqueous solutions of different composition, including with the addition of acetic acid or sodium hydroxide with various initial amounts of organic compound. The rise in the 4-nitro-2'-hydroxy-5'-methylazobenzene initial amount leads to increase in the nitro group transformation rate in the starting compound and to decrease in the azo-group transformation rate. The effect of sodium hydroxide additives in the 2-propanol aqueous solution on the nitro- and azo-groups conversion rate into 4-nitro-2'-hydroxy-5'-methyl-isobenzene is analogous to the change in the individual compounds hydrogenation rates (4-nitroaniline and 4-amino-2'-hydroxy-5'-methylazobenzene). Obtained results do not contradict the parallel-sequential scheme concept for the 4-nitro-2'-hydroxy-5'-methylazobenzene transformations. One of the directions is associated with the azo-group transformation into 4-nitro-2'-hydroxy-5'-methylazobenzene and 4-nitroaniline and 2-amino-4-methylphenol formation, and the second with the 4-nitro-2'-hydroxy-5'-methyl-isobenzene conversion through 4-amino-2'-hydroxy-5'-methyl-isobenzene by the nitro-group reducing. At the reaction end, all intermediate compounds are reduced to 2-amino-4-methylphenol and 1,4-phenylenediamine. When 2-nitro-2'-hydroxy-5'-methylazobenzene is hydrogenated, one of the directions leads to the 2-nitro-2'-hydroxy-5'-methylhydrazobenzene formation, and the second to the product containing the triazole cycle - N-oxide 2-2'-hydroxy-5'-methylphenylbenzotriazole. At the reaction end, these compounds are reduced to 2-2'-hydroxy-5'-methylphenylbenzotriazole and 2-amino-4-methylphenol and 1,2-phenylenediamine, respectively. In the solution at the sodium hydroxide presence, 2-nitro-2'-hydroxy-5'-methylhydrazobenzene transforms into the N-oxide 2-2'-hydroxy-5'-methylphenylbenzotriazole as a result of intramolecular rearrangement.

A cosurfactant is a chemical used in combination with a surfactant to enrich the properties of the primary surfactant formulation. Understanding the roles of a cosurfactant is of great importance in designing a chemical solution with desired features. Herein, we report a molecular dynamics simulation study to explore the roles of alcohol (propanol) as a cosurfactant at a brine-oil interface in chemical flooding under a typical reservoir condition (353 K and 200 bar). We demonstrate that propanol, as a cosurfactant, can be transported through oil and brine phases; such a dislocation of propanol in the system is a dynamic process. The interfacial tension between brine and oil decreases as propanol concentration in the system increases. This is because propanol can form hydrogen bonds with water molecules while it decreases the density of hydrogen bonds formed between the surfactant and water. The introduction of propanol does not always increase the local fluidity of surfactants at the interfaces. A local maximum fluidity was observed when the surfactants are more perpendicular to the interfaces. Our work should provide important insights into the design of the surfactant formulas for chemical flooding during enhanced oil recovery.

An analysis is made of the kinetic characteristics of the hydrogenation of 4-nitro- and 2-nitro-2'-hydroxy-5'-methylazobenzenes, 4-nitroaniline and 4-aminoazobenzene over skeletal nickel in neutral azeotropic 2-propanol–water mixture and in the same solvent in the presence of acetic acid or sodium hydroxide. It is found that the selectivity of the hydrogenation of these isomers to the intermediate products depends on the composition and nature of the solvent, and is determined by the rate of reactive group conversion. Compared to the process in the presence of sodium hydroxide, which suppresses the route leading to the predominant hydrogenation of the nitro group, the contribution from the transformation of azo group is considerably greater in the hydrogenation of 4-nitro-2'-hydroxy-5'-methylazobenzene in the presence of acetic acid. Adding a base to the solvent during the hydrogenation of 2-nitro-2'-hydroxy-5'-methylazobenzene accelerates the rate of nitro group conversion and the intramolecular cyclization of the intermediate compound, increasing the selectivity towards the products containing the benzotriazole cycle (particularly 2-(2-hydroxy-5-methylphenyl)benzotriazole-N-oxide). The almost linear correlation between the selectivity of the catalytic hydrogenation of isomers of nitro-2'-hydroxy-5'-methylazobenzene and the kinetic characteristics of the hydrogenation of nitro and azo groups in compounds containing a single reactive substituent at different values of medium’s pH is estimated.

This paper investigates the effects of propanol isomers enrichment on natural gas TFR engine via experiment and simulation. The results indicate that the reforming effect of TFR cylinder with n-propanol enrichment is the best, followed by that with iso-propanol, and with that of the natural gas being the worst. The impact of negative effect due to lack of fire was the most significant on the reforming effects with n-propanol enrichment, less on those with iso-propanol, and the least on those with natural gas. According to the kinetics analysis, the rate of H2 formation depends on the rates of H, O, OH, and HO2 formation. The n-propanol had the fastest production rate for H, O, OH, and HO2 radicals in the early stage of combustion, compared with iso-propanol and methane. The performance analysis of the normal cylinder shows that n-propanol enriched normal cylinders produced the lowest fuel consumption.

The catalysis of ionic liquids (ILs) in the traditional stirred reactor suffers from insufficient mass and heat transfer, which always needs a long reaction time and results in a low reaction rate. In this work, highly efficient synthesis of 1-methoxy-2-propanol via the alcoholysis reaction of propylene oxide (PO) with methanol was proposed and achieved by the combination of micro-tubular circulating reactor with the IL [N4444][Buty] catalyst. Compared with the stirred reactor, the rate of alcoholysis reaction in a micro-tubular circulating reactor was found to be significantly improved. The reaction time was remarkably shortened to 20 min from 180 min as well as the yield of 1-methoxy-2-propanol reached 92%. Moreover, the kinetic study further demonstrated that the main reaction rate to 1-methoxy-2-propanol (K1) was about 20 times larger than the side reaction rate to byproduct 2-methoxy-1-propanol (K2) in the temperature range of 363–383 K. Such combination of micro-tubular circulating reactor with IL catalysts is believed to be a class of effective process intensification technique for highly efficient synthesis of 1-methoxy-2-propanol.