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Exhaust gas recirculation (EGR) sweeps were performed on ethanol partially premixed combustion (PPC) to show different emission and efficiency trends as compared with diesel PPC. The sweeps showed that when the EGR rate is increased, the efficiency does not diminish, HC trace is flat, and CO is low even with 45% of EGR. N[O.sub.x] exponentially decreases by increasing EGR while soot levels are nearly zero throughout the sweep. The EGR sweeps underlined that at high EGR levels, the pressure rise rate is a concern. To overcome this problem and keep high efficiency and low emissions, a sweep in the timing of the pilot injection and pilot-main ratio was done at ~16.5 bars gross IMEP. It was found that with a pilot-main ratio of 50:50, and by placing the pilot at -60 with 42% of EGR, N[O.sub.x] and soot are below EURO VI levels; the indicated efficiency is 47% and the maximum pressure rise rate is below 10 bar/CAD. Low load conditions were examined as well. It was found that by placing the start of injection at -35 top dead center, the efficiency is maximized, on the other hand, when the injection is at -25, the emissions are minimized, and the efficiency is only 1.64% lower than its optimum value. The idle test also showed that a certain amount of EGR is needed in order to minimize the pressure rise rate. [DOI: 10.1115/1.4000291]

The synthesis of the gas chromatography stationary phase by molecular self-assembly of carbon nanotubes (CNTs) via a novel ethanol chemical vapor deposition process is presented. A major advantage is that ethanol was found to be an excellent carbon source that generated highly pure multiwalled carbon nanotubes with very little nontubular carbon impurities. The nanotubes were not vertically aligned but lay fiat out on the column surface in a randomly distributed configuration. The CNT phase was able to separate a wide range of organic compounds with diverse polarity and volatility, where the number of plates per meter ranged from 900 to 1280. It also showed classical chromatographic behavior and good precision. 10.1021/ac100428m

This article presents results of detailed and direct real-time observations of the wide variety of Sn[O.sub.2] nanobelt motions induced by ac dielectrophoresis (DEP) in an innovative microfluidic setup. High ac electric fields were generated on a gold microelectrode (~20 [micro]m electrode gap) array, patterned on a glass substrate and covered by a ~10 [micro]m tall polydimethylsiloxane (PDMS) microchannel. Ethanol suspended Sn[O.sub.2] nanobelts were introduced into the microchannel, and the DEP experiments were performed. Negative DEP (repulsion) of the nanobelts was observed in the low-frequency range (< 100 kHz) of the applied electric field, which caused rigid body motion as well as deformation of the nanobelts. The negative DEP effect observed in ethanol is unusual and contrary to what is predicted by the Clausius--Mossotti factor (using bulk Sn[O.sub.2] conductivity and permittivity values) of the dipole approximation theory. In the high-frequency range (~1-10 MHz), positive DEP (attraction) of the nanobelts was observed. Pearl chain formation involving short nanobelts and particles was also observed in the two DEP regimes. 10.1021/ac901287z

Two isomeric ester fuels, methyl acetate, C[H.sub.3](CO)OC[H.sub.3], and ethyl formate, H(CO)O[C.sub.2][H.sub.5], were used as model representatives for biodiesel compounds to determine the influence of fuel-specific destruction pathways on flame chemistry and also address their potential for forming air pollutants. The results indicate that H-abstraction from the methoxy group of the methyl ester leads to preferential formation of formaldehyde while H-abstraction from the ethoxy group of the ethyl ester leads to substantially greater concentrations of acetaldehyde for the ethyl formate flame.

Solid-phase microextraction fibers (SPME) were tested as tools to determine freely dissolved alcohol ethoxylate (AE) surfactants in seawater matrixes. Partitioning of a wide range of AE homologues into a 35-[micro]m polyacrylate fiber coating was linearly related to aqueous concentrations as low as submicrograms per liter, with high reproducibility. The exposure time needed to reach equilibrium between aqueous phase and the SPME fiber depended on the fiber-water partitioning coefficient ([K.sub.fw]) of the AE homologue. Specific attention was given to the influence of various matrixes on the analysis via SPME. The presence of sediment increases the uptake kinetics of AE homologues for which diffusion in the aqueous phase is rate limiting. The [K.sub.fw] in equilibrated systems was not affected by the presence of other homologues, micelles, or varying amounts of sediment phase. SPME is therefore a suitable tool for analysis of AE in sorption studies and sediment toxicity tests. A strong linear relation was observed between [K.sub.fw] and the hydrophobicity of the AE homologue, using estimated octanol-water partition coefficients. This relation can be used to predict the partitioning coefficient of any AE homologue to the SPME fiber, which facilitates the analysis of complex mixtures.

The energetics of the C F, C-Cl, C-Br, and C-I bonds in 2-haloethanols is examined by employing a combination of experimental and theoretical methods. It is concluded that the major qualitative trends exhibited by the C-X bond dissociation enthalpies for the series of compounds can be predicted by Pauling's electrostatic-covalent model.

A combination of static and dynamic laser light scattering (LLS) is used to study the aqueous solutions of tetrahydrofuran, ethanol, urea and [alpha]-cyclodextrin. The results have indicated that the formation of nanobubbles is stable and the measurement of isothermal compressibility has confirmed the existence of a low density microphase in the aqueous solutions.

Uncovering genetic control of variation in ethanol tolerance in natural populations of yeast Saccharomyces cerevisiae is essential for understanding the evolution of fermentation, the dominant lifestyle of the species, and for improving efficiency of selection for strains with high ethanol tolerance, a character of great economic value for the brewing and biofuel industries. To date, as many as 251 genes have been predicted to be involved in influencing this character. Candidacy of these genes was determined from a tested phenotypic effect following gene knockout, from an induced change in gene function under an ethanol stress condition, or by mutagenesis. This article represents the first genomics approach for dissecting genetic variation in ethanol tolerance between two yeast strains with a highly divergent trait phenotype. We developed a simple but reliable experimental protocol for scoring the phenotype and a set of STR/SNP markers evenly covering the whole genome. We created a mapping population comprising 319 segregants from crossing the parental strains. On the basis of the data sets, we find that the tolerance trait has a high heritability and that additive genetic variance dominates genetic variation of the trait. Segregation at five QTL detected has explained ~50% of phenotypic variation; in particular, the major QTL mapped on yeast chromosome 9 has accounted for a quarter of the phenotypic variation. We integrated the QTL analysis with the predicted candidacy of ethanol resistance genes and found that only a few of these candidates fall in the QTL regions.

The complex [H(ETOH)2][{OsCl([(eta).sup.4]-COD)}2(mu-H)(mu-Cl2] is prepared in high yield by treament of OsCl3.H2O with 1,5-cyclooctadiene in ethanol under reflux. It is unstable under air and undergoes oxidation by action of O2 to afford the neutral derivative {OsCl([eta.sup.4]-COD)}2(mu-H)(mu-Cl2).

An investigation on the adsorption, desorption, and reactions of ethanol is conducted on pure and promoted ZSM-5 catalysts. FTIR spectroscopy indicated the formation of a strongly bonded ethoxy species on ZSM-5(80) at 300 K.

The gene expression profiles of yeast cells during sake brewing using DNA microarray analysis are analyzed. Analysis revealed some characteristics of yeast gene expression during sake brewing and provided a scaffold for a molecular level understanding of the sake brewing process.

A novel sensor array using seven room-temperature ionic liquids (ILs) as sensing materials and a quartz crystal microbalance (QCM) as a transducer was developed for the detection of organic vapors at ambient and elevated temperatures. Ethanol, dichloromethane, benzene, and heptane were selected as representative gas analytes for various kinds of environmental pollutants and common industrial solvents. The QCM/IL sensors responded proportionately and reversibly to the organic vapor concentrations (i.e., ethanol, heptane, and benzene) in the gas phase from 0 to 100% saturation at room and elevated temperatures (e.g., 120 [degrees]C) but deviated from this linear relationship at high concentrations for dichloromethane, a highly volatile compound. Linear discriminant analysis was used to analyze the sensing patterns. Excellent classifications were obtained for both known and unknown concentrations of vapor samples. The correct classifications were 100% for known concentration samples and 96% for samples with unknown concentrations. Thermodynamics and ATR-FT-IR studies were conducted to understand specific molecular interactions, the strength of the interaction between ILs and organic vapors, and the degree of ordering that takes place upon dissolution of the vapors in ILs. The different response intensity of the QCM/IL sensors to the organic vapors depends on the different solubilities of organic vapors in ILs and varying molecular/ion interactions between each organic vapor and IL. The diverse set of IL studied showed selective responses due to structural differences. Therefore, a sensor array of ILs would be able to effectively differentiate different vapors in pattern recognitions, facilitating discrimination by their distinctive patterns in response to organic vapors in both room and high temperatures.

The study was conducted to verify the titration constants for metal ions in ethanol solution including the lanthanides and two transition metal ions, which have promoted acyl and phosphoryl, transfer from various substrates to alcohol solvents. It is shown that utility of titration/speciation analysis in kinetic analysis of [La.sup.3}- catalyzed ethanolysis of paraoxon, a pesticide used as a chemical weapons simulant.

Abstract -- The voltammetric reduction of acetaldehyde was studied in 0.1 M LiOH: LiCl (60 : 40 v/v). Well-defined waves can be seen at -1.77 and -1.60 V with the [...]

Sum-frequency spectroscopy (SFS) is used to investigate the interface between a model catalyst support ([Al.sub.2][O.sub.3]-coated Ca[F.sub.2]) and liquid consisting of neat acetonitrile and acetonitrile in ethanol. The lack of curvature in the isotherm has indicated the lack of affinity for the surface by acetonitrile in ethanol.

A liquid chromatography--tandem mass spectrometry (LC--MS/MS) method for the determination of the ethanol consumption markers ethyl glucuronide (EtG), ethyl phosphate (EtP), and ethyl sulfate (EtS) in human urine was developed. A reversed-phase/weak anion exchange type stationary phase demonstrated particular suitability for the analysis of these highly polar acids. Sample preparation was minimized to centrifugation and dilution of urine prior to injection. The method was validated in the range of 5-750 [micro]g * [L.sup.-1] with 1:20 and 1:1000 diluted urine, which corresponds to actual concentration ranges of 0.1-15 and 5-750 mg * [L.sup.-1] in undiluted samples. Method validation was carried out using six different lots of human urine. Over the entire calibration range intraday and interday precision (each n = 5, three concentration levels per dilution factor) adopted values between 0.6 and 4.7% and 0.8 and 12.1%, relative standard deviation, respectively. Corresponding accuracy values ranged between 94.2 and 113.5% and 86.6 and 110.9%, respectively. Matrix effects (absolute/relative) were found to be present in minor extent (~ -30% to +15% MS/MS signal alterations) and were well corrected by the employed isotopically labeled internal standards. The validated assay was applied to urine samples of a drinking study as well as postmortem specimens. It was possible to assess the principal potential of EtP as ethanol consumption marker. Elevated concentration levels were found in real samples; however, EtP seems to be less sensitive compared to the previously known ethanol phase II conjugates EtG and EtS.

The surface tension and dynamic light scattering (DLS) are used to investigate the surface and bulk properties of two amphiphilic penicillins cloxacillin and dicloxacillin in aqueous solution and in the presence of ethanol. The stability curves for both penicillins have indicated the predominance of electrostatic repulsion, leading to a stable system over the drug-ethanol concentration range, but the height of the reduced pair interaction potential energy barrier has deceased with ethanol concentration.

The infrared (IR) vibrational spectra of acetaminophen (N(4-hydroxyphenyl) acetamide or paracetamol) complexes formed with ethanol and acetone is investigated. It is argued that the exchange-correlation contribution taken into account in density functional theory calculations is likely significant in determining the main IR spectral features of acetaminophen complexes formed with acetone or involving hydrogen-bonded as with ethanol.

ZrO2-carbon nanotube (CNT) composites are synthesized through decomposition of Zr(NO3)4.5H2O in supercritical carbon dioxide-ethanol solution with dispersed CNTs at relatively low temperatures and the samples are characterized using various spectroscopies. The chemiluminescent sensor prepared from ZrO2-carbon nanotube composites has displayed dramatic sensitivity as well as high stability and selectivity to ethanol.

The solubility of gas phase ethanol in aqueous sulfuric acid solutions was measured in a Knudsen cell reactor over ranges of temperature and acid composition. No evidence for the formation of ethyl hydrogen sulfate was found under the experimental conditions.

The uptake of ethyl alcohol (ethanol) vapor by sulfuric acid solutions over the range ~40 to ~80 wt % [H.sub.2]S[O.sub.4] were investigated. Laboratory studies used a fast flow-tube reactor coupled to an electron-impact ionization mass spectrometer for detection of ethanol and reaction products.

The quasichemical model of the nonideal associated solution (QCNAS) was used to analyze the excess thermodynamic functions and permittivity of cyclohexane-ethanol mixtures in the entire range of compositions and in a wide temperature range. The results show that a relatively low fraction of cyclic nonpolar alcohol aggregates essentially influences the properties of cyclohexane-ethanol solution as whole and, in particular dielectric properties of dilute solutions.

The first example of a thermomorphic system for asymmetric hydrogenation and liquid/solid separation of the chiral catalyst is reported. The new BINAP derivative bearing alkyl ponytails proved to be a highly effective ligand for Ru-catalyzed hydrogenation of beta-ketoesters in the mixture of ethanol/1,4-dioxane.

Raman spectroscopy was used to examine the interactions of the free O-H bonds in n-octanol and ethanol with the organic solvents carbon tetrachloride [CCI(sub 4)], cyclohexane, and benzene. These spectra reveal that the solvents CCI(sub 4) and cyclohexane have a small effect on the free O-H peak of alcohols, whereas benzene as a solvent significantly red shifts the free O-H band.

A silver-free synthetic route is described for the synthesis of a number of Pt and Pd NCN pincer complexes containing hydroxy- and mercaptopyridine ligands. The X-ray crystallographic analysis shows that the binding mode of the substituted pyridine ligand is dependent on the type of heteroatoms present and the pyridine ring in the NCN-M thiolate systems is free of subsequent reactivity.

The novel pyridine-containing 14 membered macrocycle 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,-15-triene (L), which contains an N(sub 2)S(sub 2) donor set was synthesized and its protonation behavior was studied. The reactions between L and NiX(sub 2).6H(sub 2)O in ethanol or acetonitrile afforded the octahedral complexes and the square -planar complex [Ni(L)]-(X)(sub 2) were obtained by heating these octahedral complexes.

The dehydrogenation and decarbonylation of ethylene glycol and ethanol was studied using temperature programmed desorption on Pt(111) and Ni/PT(111) bimetallic surfaces. The reforming activity was correlated with the d-band center of the surface and displayed a linear trend for both ethylene glycol and ethanol, with activity increasing as the surface d-band center moved closer to the Fermi level.

The N-doped TiO(sub 2) layer was prepared by pretreating the TiO(sub 2) precursor in the NH(sub 3)/ ethanol fluid under supercritical, denoted as TiO(sub2)N(SC). The activity of the TiO(sub 2)N(SC) first increased and then decreased with the increase ind the N-content.

The reaction rate of the Diels-Alder reaction between N-ethylmaleimide and 9-hydroxymethylanthrance in CO(sub 2) + ethanol and CO(sub 2) + hexane mixed solvents of different compositions were determined by in situ UV/vis spectroscopy at 318.15 K and different pressures. The result states that at the same temperature the reaction can not be conducted in pure supercritical CO(sub 2) in the highly compressible region due to the solubility limitation of 9-hydroxymethylanthrance in supercritical CO(sub 2) at the lower pressures, while the reaction can be carried out in the highly compressible mixed solvents, and reaction rate is effective by pressure.

The conformation effects on the sigma profiles, the vapor pressure predictions, and the vapor-liquid equilibrium (VLE) predictions were investigated for 1-hexanol, and 2-methoxy-ethanol. The results showed that the sigma profile for 1-hexanol varies only slightly using different conformations, while the sigma profile of 2-methoxy-ethanol shows a significant difference between the liquid and vapor phases.

The role of intracellular L-proline in cells of Saccharomyces cerevisiae grown under ethanol stress is evaluated. The strain that could accumulate L-proline was used to brew sake containing five times more L-proline than what is found in sake crewed with the control strain, without affecting the fermentation profiles.

An inverse metabolic engineering approach is used to identify gene targets for improved xylose assimilation in recombinant Saccharomyces cerevisiae. The results indicate that open reading frame (ORF) designated PsTAL1 is a better gene target for engineering of the pentose phosphate pathway in recombinant S. cerevisiae.

The effects of temperature on rates and pathways of CH4 production and on the abundance and structure of the archaeal community are examined in acidic peat from mire in northern Scandinavia. The results have shown that the ethanol pool was oxidized to acetate by syntrophic oxidation with methanogenesis as an H2 sink and as a reductant for Fe(III).

The effect of water on diamond synthesis was investigated in the hot-filament chemical vapor deposition process under atmospheric pressure. An ethanol-water-hydrogen system is adopted where an ethanol-water mixture was supplied by an electrospraying technique.

The dynamics of the B-A transition of DNA double helices with different GC contents and various chain lengths are characterized by an electric field pulse technique. The results show that the main features of the B-A dynamics in natural DNA are similar to those of poly[d(A-T)], though there is some difference in detail, revealing a special signature of GC base pairs in the B-A dynamics.

Rate constants and product selectivities are reported for solvolyses of chloroacetyl chloride at 10 degree Celsius and phenylacetyl chloride at 0 degree Celsius in ethanol/ and methanol/water mixtures. The reasons for change in reaction channels are discussed in terms of the gas-phase stabilities of acylium ions, calculated using Gaussian 03.

A novel class of four-connecting three-dimensional molecular 2-5 based on biaryls for supramoelcular self-assembly is synthesized. The X-ray crystal structure analysis of tetraphenol with ethanol reveals a novel O-H...O hydrogen-bonded helical self-assembly in three dimensions leading to the generation of channels in the crystal lattice.

A procedure is described for acyloxyallylation of unprotected aldoses with two functionalized reagents, namely, 3-bromopropenyl acetate and 3-bromopropenyl benzoate. The reaction is performed in ethanol or a dioxane/water mixture in the presence of indium metal.

The reactions of anilines with 4-nitrophenyl, 4-methylphenyl, and 4-chlorophenyl 4-nitrophenyl carbonates are studied in the aqueous ethanol, to clarify the mechanisms of the aminolysis of diaryl carbonates. The main goal is to evaluate the influence of the amine nature and that of the leaving and nonleaving groups of the carbonate on the kinetics and mechanisms.

Closed loop automated pulse shaping experiments are conducted to investigate population transfer in solutions of the laser dye LD750 in acetonitrile and ethanol. It is concluded from the weak solvent dependence that rapid spectral evolution in emission of LD750 is not strongly altered by the shift between these solvents.

Large-angle X-ray scattering (LAXS) measurements are made at 298 K on 2,2,2-trifluoroethanol (TFE), 2,2,2-trichloroethanol (TCE), and their aqueous mixtures to clarify the structure of solvent clusters formed in halogenoethanol-water mixtures at the molecular levels. The most likely structure models of solvent clusters predominantly formed in TFE-water and TCE-water mixtures are proposed.

The effect of CO2 on the phase behavior of the reaction system and equilibrium conversion for esterification of acetic acid and ethanol in ionic liquid is studied at 60.0 degree Celsius up to 15 MPa. There is only one phase in the reaction system in the absence of CO2 and the pressure of CO2 or the phase behavior of the system affected the equilibrium conversion of the reaction markedly.