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N-butanol is well known to be a flammable and harmful liquid that is a potential threat to human health and property. Therefore, it is important to monitor the concentration of n-butanol in the surroundings. The need for highly efficient toxic gas detection is urgent and has been driving the research on gas sensors for practical applications. Molybdenum disulfide (MoS2) has been attracting significant interest for gas detection at room temperature. Herein, we report biofunctionalized magnetic nanoparticles incorporated MoS2 for sensing n-butanol. The biosynthesized magnetite nanoparticles (CT-Fe3O4) were synthesized by the addition of Cinnamomum Tamala (CT) leaf extract, and subsequently, the nanocomposite was synthesized using a hydrothermal method. Highly sensitive sensors based on MoS2-CT-Fe3O4 were fabricated and tested for sensing different concentrations of n-butanol. The nanocomposites showed a good sensing performance (Δ R/Rair %) of 72% towards 20 ppm of n-butanol, indicating the potential use of MoS2-CT-Fe3O4 nanocomposite for sensing n-butanol at room temperature. [ABSTRACT FROM AUTHOR]

Catalysts based on KL-zeolite exchanged with alkali metal ions (Rb+ and Cs+) were studied for conversion of ethanol to oligomerization through the Guerbet reaction pathway. The catalysts were characterized by techniques such as ICP-AES, FESEM-EDX, N2-adsorption-desorption, and CO2-TPD to assess their physio-chemical properties. Effects of operating parameters, namely reaction temperature, pressure, and feed flow rate on catalytic activity for the conversion of ethanol to n-butanol were examined. Furthermore, influence of alkali metal loading on KL-zeolite was explored. Substantial ethanol conversion (42.6%) and n-butanol yield (13.9%) were achieved at 450°C and 30 kg/cm2 after a 6 h reaction employing Cs-KL zeolite catalyst. Observations indicated that the butanol selectivity is highest among the reported literature. Additionally, this catalyst has exhibited low deactivation rate attributable to coke formation. Spent catalysts were studied for XRD and DTG/TGA analysis. Present investigation establishes that KL-zeolite, particularly when modified with alkali metal ions, proves to be an efficient catalyst for the Guerbet conversion of ethanol, highlighting its potential for ethanol upgrading. [ABSTRACT FROM AUTHOR]

In this paper, we studied the alcohol-sensing properties of CoMn2O4 nanoparticles for the first time. The CoMn2O4 nanoparticles were prepared via a simple microwave-assisted colloidal method using cobalt nitrate, manganese nitrate, dioctyl sulfosuccinate sodium salt, and ethylene glycol as a solvent. Various techniques were used to characterize the structural, morphological, and optical properties of CoMn2O4. The crystal structure of CoMn2O4 was found after calcination at a temperature of 400 °C. The Raman spectrum showed seven vibrational bands, while the optical absorption spectrum showed three bands, confirming the spinel CoMn2O4. Morphological analysis revealed that the porous microstructure of CoMn2O4 was composed of nanoparticles with a size distribution of 16 to 58 nm. Gas sensors were fabricated with the CoMn2O4 powders calcined at 400 °C using the brush-coating method, and experimental results showed that CoMn2O4 nanoparticles were more sensitive to n-butanol than isopropanol and ethanol at an operating temperature of 185 °C. The CoMn2O4 sensor showed a response of 6.6 at 50 ppm n-butanol with good stability, reproducibility, and repeatability. The present article provides a new sensing material that could be used as an n-butanol sensor with significant benefits for human health. [ABSTRACT FROM AUTHOR]

The adsorption/desorption of n-butanol and butyl acetate on the SiO2 surface was studied experimentally by thermokinetic spectrometry and computer molecular dynamic (MD) simulations (temperature, energy, and structural characteristics of adsorption). Radial distribution function (RDF) profiles were constructed and analyzed based on the MD modeling data for the "surface (SiO2)–carrier gas (Ar)–target molecule (n-butanol/butyl acetate)" ternary system at three temperatures of the system: T = 300, 500, and 700 K. A comparative analysis of the results suggests that the addition of an acetate group enhances the affinity of the butyl acetate molecule for the SiO2 surface. Consequently, the adsorption of butyl acetate occurs more completely at higher temperatures compared with the adsorption of n-butanol. In addition, changes in the size influence the atomic arrangement in the butyl acetate molecule relative to the SiO2 surface atoms, leading to the observed "displacement" of the carbon skeleton atoms of the ( – – – – ) chain for both (n-butanol and butyl acetate) molecules. According to the experimental data on n‑butanol and butyl acetate desorption from the SiO2 surface in the n-butanol/SiO2/argon (butyl acetate/SiO2/argon) ternary system, the activation energy of desorption is 78.83 (87.58) kJ/mol, and the pre-exponential factor is 4.41 × 107 (1.81 × 1010) s–1. [ABSTRACT FROM AUTHOR]

The goal of this study is to see how greater the exhaust gas recirculation (EGR) and quaternary blend approach affect the performance, emission, and combustion parameters of a Common Rail Direct Injection (CRDI) engine with various quaternary blends. In this study, we will use bio-fuels in replacement of diesel by 30–40% that emits less oxides of nitrogen (NOx) and soot. In light of this, combustion, exhaust emissions, and performance parameters of 1-cylinder CRDI engine powered by quaternary blends (QB) of diesel, vegetable oil, biodiesel, and 1-butanol by volume% were explored experimentally. To determine the effect on engine characteristics, with no EGR, 6% EGR and 12% were evaluated with various blends and base fuels. At peak load with 12% EGR, the experimental examination revealed a 2-percent decline in brake thermal efficiency (BTE), a small rise of 3.8% in brake-specific fuel consumption (BSFC) among blends in performance. In emissions, 12% EGR rate reported best results, i.e. average of 54% NOx reduction among blends, 14% rise in hydrocarbon (HC) and carbon monoxide (CO) at full load. The maximum NOx reduction has been reported by QB3 blend at 12% EGR rate and at full load is 54%. EGR rate of 12% was helpful in decreasing NOx emissions in a greater extend while little sacrificing in HC and CO. [ABSTRACT FROM AUTHOR]

Herein, a novel Co3O4/ZnO heterostructured composite was successfully fabricated using a facile one-pot method in combination with subsequent heat treatment, which showed excellent performance in detecting n-butanol. The crystal structure, micromorphology, pore structure, molecular structure, and surface elemental valence structure of the composite were subjected to systematic characterization including XRD, TEM, SEM, BET, and XPS techniques. It was demonstrated that Co3O4/ZnO composite mainly existed in the form of mesoporous pores with an average pore size of 46.64 nm. While applied in gas sensing experiments, all sensors tended to increase at 280 °C and then decreased as the temperature continued to rise. Furthermore, at each working temperature, the response values of Co3O4/ZnO sensors outweighed that of pure ZnO sensors, with Co3O4/ZnO-2 sensor (108) six times greater than pure ZnO (18). The response recovery time also exhibited a 25 s and 10 s improvement, respectively. Eventually, the behind gas sensitivity mechanism of Co3O4/ZnO sensor was explored and the formation of heterojunctions and bigger pore sizes in composites was proved to be key contributors to the improved gas sensitivity. [ABSTRACT FROM AUTHOR]

Oxygen oxidation of the styrene epoxide (SE)–p-toluene sulfonic acid (TSA) double system (DS) in solutions of three primary alcohols, 1-octanol (OCT), n-butanol (BUT), and ethanol (ET), is studied. The corresponding concentration expressions of oxidation rates are as follows: VOCT = k [SE]0 [TSA]1, VBUT = k [SE]0 [TSA]0.63, and VET = k [SE]0 [TSA]0.7 at [SE] [TSA]. The proximity of the oxidation activation energies in three alcohols contrasts with the difference in the oxidation rates: the oxidation rate in ET is three times the rate in n-butanol and thirty times the oxidation rate in 1-octanol. [ABSTRACT FROM AUTHOR]

The kinetics of butyl lactate production by the interaction of ammonium lactate with n-butanol in the presence of water in the temperature range of 130–170°C in a closed system was studied for the first time as one of the stages of a new integrated technology for the production of lactic acid and polylactide. Also for the first time, a reaction scheme and kinetic model of ammonium lactate esterification with n-butanol were proposed, taking into account the side formation of lactamide and the acid catalysis of esterification by lactic acid. The developed kinetic model can be used for mathematical modeling of a reactor for the synthesis of butyl lactate. [ABSTRACT FROM AUTHOR]

Flame spread over a thin film of various liquid fuels with an flash point below ambient temperature has been studied experimentally using thin copper and thick glass substrates in environments with different oxygen concentrations. It has been shown that with an increase in the oxygen concentration, the flame speed increases faster than the normal speed of the corresponding homogeneous stoichiometric mixture. When the proportion of oxygen in the mixture with nitrogen was changes from 0.21 (air) to 1, the flame speed changes from 0.02 to 2.4 m/s. At flame speeds above 0.3 m/s, the thermal thinness condition is not satisfied even for thin copper substrates. The flame speed ceases to depend on the substrate properties and the fuel layer thickness and becomes dependent only on the fuel properties. In this speed range, the flame speed increases linearly with increasing thermal effect of a unit volume of the stoichiometric mixture of fuel vapor with oxidizer and decreases with increasing difference between the temperature of formation of the stoichiometric composition under equilibrium conditions and the ambient temperature . [ABSTRACT FROM AUTHOR]

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Unsustainable energy sources are one of the preeminent supply specks of power generation in the prevailing scenario. The production and utilization of energy have brought about serious ecological effects all over the globe. Exceptionally unpredictable fossil fuel expenses are making increasingly more ambiguity for the worldwide economy while simultaneously giving an ambiguous motivation for putting resources into sustainable power source advancements, which are now accepted as a viable solution. Biodiesel, higher alcohol, and gaseous fuel are considered to be suitable replacements for dwindling natural resources. These substitute fuels not only aid in enhancing the engine performance but also cooperate in contracting the injurious tailpipe emissions. In this review article, a study has been made to evaluate the domination of biodiesel, n-butanol, and biogas on the performance and emission characteristics of the diesel engine in comparison to fossil diesel. Conclusions of empirical analysis considering emission and performance characteristics with different permutation and combination are put forwarded to understand the commuted result on various characteristics of the diesel engine. The comprehensive study recommends that the performance characteristics of the engine degrade with substitute fuels, whereas its emission characteristics are depicted to have abated. [ABSTRACT FROM AUTHOR]

The growing population increases the need to develop advanced biological methods for utilizing renewable and sustainable resources to produce environmentally friendly biofuels. Currently, energy resources are limited for global demand and are constantly depleting and creating environmental problems. Some higher chain alcohols, like butanol and ethanol, processing similar properties to gasoline, can be alternate sources of biofuel. However, the industrial production of these alcohols remains challenging because they cannot be efficiently produced by microbes naturally. Therefore, butanol is the most interesting biofuel candidate with a higher octane number produced naturally by microbes through Acetone–Butanol–Ethanol fermentation. Feedstock selection as the substrate is the most crucial step in biobutanol production. Lignocellulosic biomass has been widely used to produce cellulosic biobutanol using agricultural wastes and residue. Specific necessary pretreatments, fermentation strategies, bioreactor designing and kinetics, and modeling can also enhance the efficient production of biobutanol. The recent genetic engineering approaches of gene knock in, knock out, and overexpression to manipulate pathways can increase the production of biobutanol in a user friendly host organism. So far various genetic manipulation techniques like antisense RNA, TargeTron Technology and CRISPR have been used to target Clostridium acetobutylicum for biobutanol production. This review summarizes the recent research and development for the efficient production of biobutanol in various aspects. [ABSTRACT FROM AUTHOR]

The energy efficiency of using nonadiabatic distillation in the process of extractive distillation of an acetone–chloroform–n-butanol mixture with dimethylformamide as an entrainer is evaluated. Two options for organizing heat integration are considered: (1) between the regeneration column of the entrainer and the extractive column; and (2) between the regeneration column, the extractive column, and the chloroform-recovery column. It is shown that the use of nonadiabatic distillation schemes makes it possible to decrease the energy consumption by 7.4–12.7% during heat integration between the extractive distillation and dimethylformamide regeneration columns; in the case of heat integration of all columns of the scheme, energy consumptions is reduced by up to 20% compared to the original scheme. [ABSTRACT FROM AUTHOR]

Copper nanoparticles on silica support are cheap and effective catalysts for dehydrogenation of n-butanol, a biomass-derived building block which is increasingly used. Ultrasonically assisted Cu catalysts are prepared, characterized, and tested for the conversion of n-butanol to n-butanal. The best performance in terms of overall conversion of n-butanol and selectivity to butanal was offered by ultrasound-prepared process of the Cu nanoparticles. In conventional wet impregnation method, Cu nanoparticles on the surface of support tend to aggregate in some sort of cubic aggregates with the size of 4–5 µm and because of this, the percentage of the centers of silica (on which intermolecular dehydration reactions occur) is higher compared to Cu metallic centers (that promotes the dehydrogenation reaction). The ultrasound reduction stage used in the preparation of catalysts provides a better coverage of the catalyst surface by Cu nanoparticles that have a more uniform dimension, which offers a greater selectivity to butanal (more than 95%) and a negligible selectivity to butene. [ABSTRACT FROM AUTHOR]

At present, IC engines are the primary power source in transit and must never be modified. The palm oil was collected from the palm tree and used in an internal combustion engine as an alternative fuel. In the present investigation, the palm oil is preheated to 110 °C using a heat exchanger to get a homogeneous mixture. The two additives, i.e., butylated hydroxytoluene (BHT) and n-butanol, were combined with preheated palm oil. The four fuels were prepared PN100, PND20, PND20 mixing with the 2000 ppm BHT of 1000 mL oil and other blends preheated PND20 palm oil mixing with the 2000 ppm n-butanol of 1000 mL oil. The blend 20 brake thermal efficiency was increased by 11.70% when compared with the mineral fuel, because the proper air–fuel mixture takes place. The oxides of nitrogen and smoke opacity were decreased by 15.32% and14.53%, respectively, for the blend of preheated palm oil and n-butanol as compared to mineral fuel due to the burning of more fuel through the combustion process. The hydrocarbon and carbon monoxide emissions were decreased for PND20AB and PNDAN blends by 35.71% and 14.53%, respectively, as compared to diesel. The preheated palm oil mixed with antioxidants was utilized as the alternative fuel in the conventional engine. [ABSTRACT FROM AUTHOR]

Ethanol Guerbet condensation (EGC) is a green process for preparing n-butanol and the development of highly effective solid catalysts is still the bottleneck of this reaction. In this work, a series of multifunctional catalysts Ni–X/TiO2 (X = Ru, Pt, Ir, Au, Cu, Mn, Co, Fe) were prepared by a co-impregnation method in order to improve the catalytic performance, especially the stability. It was found that the addition of the second metal component changed the acidity and alkalinity of Ni/TiO2 catalyst. What is more, acid site number affected ethanol conversion while alkali site number affected n-butanol selectivity. Among the Ni–X/TiO2 catalysts, Ni–Cu/TiO2 showed the best catalytic performance. The effects of preparation conditions on the catalytic performance of Ni–Cu/TiO2 were investigated and the results showed that the suitable preparation conditions were as follows: a Ni/Cu mass ratio of 59 : 1, a Ni–Cu loading of 12.5 wt %, a calcination temperature of 450°C, a calcination time of 2 h, a reduction temperature of 400°C, and a reduction time of 4 h. At a 10 wt % of catalyst loading, a reaction temperature of 210°C and a reaction time of 10 h, the ethanol conversion and the selectivity of n-butanol were 47.9 and 44.4%, respectively. Moreover, the stability of Ni–Cu/TiO2 catalyst was greatly improved due to the interaction between Ni and Cu as compared with the Ni/TiO2 catalyst: the catalytic activity of Ni–Cu/TiO2 did not decline significantly for reuse in three cycles. [ABSTRACT FROM AUTHOR]

Dilution of diesel/biodiesel fuel with n-butanol in engines has a significant role in reducing the pollutants and improving the performance of compression ignition engines. This can be achieved using microfluidic networks, which allow an optimum dilution ratio to be precisely defined in an automated and controlled manner. This paper presents a novel, comprehensive study for such a process. The dilution profile of n-butanol-diesel/biodiesel fuel blends in a microfluidic hierarchical network system was predicted at different conditions. An analytical model was provided for the prediction of the variables' distribution within the network. The model allowed for a wide range of n-butanol-diesel/biodiesel blends dilution to be investigated and validated experimentally and with CFD simulations. The mathematical model proved successful, returning precise results. Excellent agreement was found with the real data for the distributions of the variables within the network including the volume fractions, viscosity, and density. It showed that mixing 10 vol% with 90 vol% of n-butanol in diesel fuel resulted in maximum deviations of: 0.037% and 0.061% in the volume fractions of outlet streams; 0.19% and 0.08% in the density, and 2.32% and 14.13% in the viscosity, from the experimental and CFD simulation results, respectively. In addition, finer dilution of 30 vol % n-butanol in diesel fuel with 10 vol% n-butanol in diesel fuel showed maximum deviations of 0.006% and 0.08% in the volume fraction, 0.018% and 0.008% in the density, and 2.86% and 14.27% in the viscosity distribution, from the experimental and CFD simulations, respectively. The network's performance with n-butanol-biodiesel blends compared with n-butanol-diesel blends was also presented. This study is of great importance for optimizing alcohol ratios in diesel/biodiesel for the best engine performance and minimum greenhouse gas emissions. It also allows for predicting the properties of un-experimented ratios of blends. Possible applications of this study include areas where precise control of the additives to diesel/biodiesel has a significant effect such as improving the lubricity in an engine, monitoring the fuel droplets, and/or precisely specifying the fuel spray characteristics. [ABSTRACT FROM AUTHOR]

In the present work, Ni-M/TiO2 (M = Au, Pt, and Ir) were prepared and their catalytic performances were evaluated for ethanol Guerbet condensation. The characterization and evaluation results showed that the addition of noble metal adjusted the acid–base properties of catalyst and improved its catalytic performance. The number of acid sites of catalyst promoted the conversion of ethanol while the strength of basic sites of catalyst boosted the formation of n-butanol. Ni-Pt/TiO2 presented the best catalytic performance: n-butanol selectivity of 48.1% was reached at an ethanol conversion of 40.0% at 210 °C and 10 h. Furthermore the catalytic stability of Ni-Pt/TiO2 was improved significantly; it was used for 3 runs without a significant loss in its catalytic performance. [ABSTRACT FROM AUTHOR]

Dwindling petroleum products and environment degradation, owing to the gases from the exhaust tailpipe of compression ignition engines, have obligated the investigators to invent some unconventional fuel. Current experimentation aimed to evaluate the combustion, performance and emission characteristics of a dual fuel engine by using blends of diesel and n-butanol as pilot fuel with biogas as primary fuel. Under dual fuel mode, biogas at different mass flow rates (0.5, 1.2 and 2.0 kg h−1) was admitted into the engine through inlet manifold and blends of n-butanol with diesel (D90/nb10 and D80/nb20) were injected as a pilot fuel to initiate the combustion. The fuel properties of the tested fuels were measured as per ASTM standards. The engine testing was carried out at constant speed of 1500 rpm and different engine loads. The experimental results depict that under dual fuel mode, brake-specific fuel consumption increased by 22.6% and brake thermal efficiency of the engine decreased by 11.9% in comparison to conventional diesel. As far as emissions are concerned, carbon monoxide and hydrocarbon emissions increased by 50.8 and 11.9%, respectively, whereas NOx and smoke opacity decreased by 19.8 and 40.9%, respectively, when compared to conventional diesel. Thus, such fuel combinations can be used in existing diesel engines for addressing long term energy needs and solving environmental associated challenges. [ABSTRACT FROM AUTHOR]

This paper presents the results of investigations on the removal of cyclohexane vapors from air using a peat-perlite packed biotrickling filter. Effects of basic process parameters i.e. inlet loading and empty bed residence time as well as introduction of n-butanol to the treated air stream and starvation periods on the process performance were evaluated. The results show that the introduction of hydrophilic n-butanol results in an enhanced removal of hydrophobic cyclohexane comparing to the experiments where only cyclohexane was treated. Additionally, the biotrickling filter performance after the starvation events is regained to more extent for mixed system than for the single cyclohexane. A novel and interesting element of the paper is the application of an electronic nose for the process monitoring. Obtained results are discussed in the perspective of an influence of the presence of a compound with different affinity to aqueous phase on the removal efficiency of the compound with opposite chemical properties. [ABSTRACT FROM AUTHOR]

Organic acids are produced as by-product in food waste by acid fermentation process for biogas production. Particularly, butyric acid is one of the main organic acids and can be converted to n-butanol via the butyrate kinase pathway. However, bacterial toxicity of butyric acid limits its use as a major carbon source. Here, we produced n-butanol from butyric acid using Clsotrdium beijerinckii KCTC 2203, which was the most suitable strain among the six Clostridia strains tested. We produced up to 9.84 g/L of n-butanol using a mixed carbon source composed of 25 g/L of glucose and 10 g/L of butyric acid in a flask culture. The pH-stat fed-batch fermentation method was also performed to increase the production rate. To maximize the effect of pH-stat feeding, substrate feeding solutions with various butyrate/glucose (B/G) ratios were fed. As a result, 9.69 g/L of n-butanol could be produced at a B/G ratio of 0.5, and the pH-stat fed-batch feeding strategy exhibited an enhanced n-butanol production rate of 0.40 g/L/hr without substrate depletion. Finally, we integrated this method with gas stripping using the volatility of n-butanol to prevent product inhibition, resulting in the production of 41.27 g/L of n-butanol in 124 h. [ABSTRACT FROM AUTHOR]

Ethanol conversion into n-butanol was performed over ZrO2–CeO2 mixed oxide catalysts. The effect of ceria content on the acid–base and catalytic properties of ZrO2–CeO2 compositions has been studied. The introduction of CeO2 additives into zirconia stabilizes the tetragonal phase of ZrO2 leading to an increase in basicity of the samples and, as a result, increases the activity of catalysts towards n-butanol. The highest ethanol conversion, selectivity and the rate of n-butanol formation were obtained over the ZrO2–CeO2 sample with 10% of ceria, which exhibited the highest concentration and strength of base sites. This sample consists of a solid solution of ZrO2–CeO2, whereas at higher concentrations of additive, CeO2 forms an individual phase. [ABSTRACT FROM AUTHOR]

NAD(P)H-dependent enzymes are ideal biocatalysts for the industrial production of chiral compounds, such as chiral alcohols, chiral amino acids, and chiral amines; however, efficient strategies for the regeneration of coenzyme are expected as costly of the coenzymes. Herein, a solvent-tolerant isopropanol dehydrogenase (IDH) showing lower similarity (37%) with other proteins was obtained and characterized. The enzyme exhibits high catalysis ability of its substrates methanol, ethanol, ethylene glycol, glycerol, isopropanol, n-butanol, isobutanol, and acetone. And it has good adaptability in organic solvents (isopropanol, acetonitrile, acetone, and acetophenone). Interaction force and the corresponding amino acid residues between IDH and NAD+ or NADP+ were parsed by docking. The wide substrate spectrum, excellent organic solvent tolerance, and good biocatalytic activity make the excavated enzyme a promising biocatalyst for the production of chiral compounds industrially and the construction of coenzyme regeneration systems in aqueous organic phase or organic phase. [ABSTRACT FROM AUTHOR]

The present work is aimed at developing an n-butanol sensor based on the chemi-resistive principle using MoO3 nanostructures as a sensing element. Highly ordered free-standing α-MoO3 nanobelts were synthesized using hydrothermal technique. The synthesis parameters adapted in the present work have paved a way in obtaining distinct MoO3 nanostructure with minimal process time as compared with the earlier reports. Initially, the formation of monoclinic crystals with an end centered lattice of β-Mo9O26 was observed, which then is transformed into orthorhombic α-MoO3 on calcination at 450 °C for 5 h. XPS profiles of the nanobelts revealed the presence of molybdenum and oxygen in a stoichiometric ratio of 2.6. Penta- and hexa-coordinated defect centers of Mo5+ and oxygen vacancies were observed from the photoluminescence spectra. The nanobelts respond to n-butanol vapors at room temperature with a 75-fold signal increase and response-recovery times of 17 & 10 s, respectively. The lowest detection limit is 1 ppm. The influence of relative humidity on the sensing response was also studied. [ABSTRACT FROM AUTHOR]

The reaction of the synthesis of benzylbutyl ether via the intermolecular dehydration of benzyl and n-butyl alcohols under the action of copper-containing catalysts is studied by mathematical means. The mechanism of the reaction was proposed, and the values of kinetic parameters are determined. A comparative analysis of the activation energies of possible stages of chemical conversions is performed, and possible routes of the reactions and the catalytic cycles of reactions are determined. Variations in stage rates and the concentrations of all substances participating in the reaction are analyzed. [ABSTRACT FROM AUTHOR]

Currently, production of high-purity hydrogen (H2) in a viable and sustainable manner is highly sought. H2 generation is possible by water splitting or biomass conversion as renewable resources. Bio-based n-butanol is a potential candidate for H2 production via catalytic steam reforming (SR) which is both of industrial and scientific significance. In the current work, a new catalyst is developed using La–Mg-based mixed metal oxide as support loaded with Ni–Cu as metals promoted by a suitable noble metal from Pt, Ru and Pd for steam reforming of n-butanol (SRB) in a fixed bed reactor. The effects of temperature, steam to carbon (S/C) ratio and gas hourly space velocity on hydrogen production from n-butanol were studied systematically. High n-butanol conversion (> 75%) and H2 yield (> 70%) were obtained. Particularly, the promotion with Pt resulted in the highest H2 concentration (> 90 mol%) with long-term stability of 25 h. The process optimization studies revealed that at T = 773 K, steam/carbon ratio (S/C) = 6 mol/mol and GHSV = 3120 h−1, maximum H2 concentration was obtained. The promotion with noble metals was further justified by the absence of coke formation and minimal metal sintering because noble metals help avert oxidation of Ni and Cu maintaining their active form. It was further bolstered through the cyclic stability studies which demonstrated that all catalysts remained stable for longer periods. A possible reaction mechanism on the synthesized catalysts is proposed in consonance with experimental data. [ABSTRACT FROM AUTHOR]

The effects of different n-butanol blending ratios (Rb) on the formation of propargyl radical (C3H3), an important benzene precursor, during the combustion of n-butanol/n-butane blends are studied. A detailed kinetic combustion model of n-butanol/n-butane is developed and the premixed n-butanol/n-butane flames are calculated at an equivalence ratio of 1.5, an initial pressure of 1.0 atm, and a temperature range from 800 to 2000 K in a perfectly stirred reactor (PSR), with Rb varying from 0 to 1.0. The results show that under the investigated conditions, the peak value of the mole fraction of C3H3 decreases non-linearly with the increase of Rb. Due to the interaction between combustion products of n-butane and n-butanol during the combustion process, the actual peak mole fraction of C3H3 is higher than the theoretical value. A rate of production (ROP) analysis reveals that the number of β-carbon atoms in the molecule of n-butane and n-butanol affects the efficiency of H-abstraction reactions in generating 2-butyl (sC4H9) and C4H8OH-3 (CH3–*CH–CH2–CH2–OH), which are the two major original sources of C3H3. For both n-butane and n-butanol, the main pathway of forming C3H3 from propene (C3H6) is basically the same, which is C3H6 → C3H5-a (symmetric allyl radical) → C3H4-a (allene) → C3H4-p (propyne) → C3H3. When Rb ranges from 0.4 to 0.6, the deviation degrees of the peak mole fraction of the involved C3 species reach a maximum, indicating that the interaction between the two fuels is the most significant. The non-linear decrease in the mole fraction of C3H3 can attribute to three reasons: (a) the increase of Rb promotes the increase of the conversion ratios of n-butane to sC4H9 and n-butanol to C4H8OH-3; (b) the contribution ratios of the reactions involved in the C3H5-a → C3H4-a → C3H4-p → C3H3 pathway decrease with increasing Rb; (c) C3H5-t (tertiary allyl radical) → C3H4-p → C3H3 is the secondary pathway for the formation of C3H3. With the increase of Rb, the dependence of C3H4-p on C3H5-t increases and the conversion ratio of C3H5-t to C3H4-p increases. This study investigates the non-linear decrease of the mole fraction of C3H3 by revealing the interactions between n-butanol and n-butane during the combustion, which can help better understand the effect of n-butanol on the formation of benzene. [ABSTRACT FROM AUTHOR]

n-Butanol represents a key commodity chemical and holds significant potential as a biofuel. It can be produced naturally by Clostridia species via the ABE pathway. However, butanol production via such systems can be associated with significant drawbacks. Therefore, substantial efforts have been made toward engineering a suitable industrial host for butanol production. For instance, we previously generated a metabolically engineered Saccharomyces cerevisiae strain that produces ~300 mg/L butanol from combined endogenous and exogenous pathways. In this current study, the endogenous and exogenous pathways of butanol production were further characterised, and their relative contribution to the overall butanol titre was assessed. Deletion of any single component of the exogenous ABE pathway was sufficient to significantly reduce butanol production. Further evidence for a major contribution from the ABE pathway came with the discovery that specific yeast deletion mutants only affected butanol production from this pathway and had a significant impact on butanol levels. In previous studies, the threonine-based ketoacid (TBK) pathway has been proposed to explain endogenous butanol synthesis in ADH1 mutants. However, we find that key mutants in this pathway have little impact on endogenous butanol production; hence, this pathway does not explain endogenous butanol production in our strains. Instead, endogenous butanol production appears to rely on glycine metabolism via an α-ketovalerate intermediate. Indeed, yeast cells can utilise α-ketovalerate as a supplement to generate high butanol titres (> 2 g/L). The future characterisation and optimisation of the enzymatic activities required for this pathway provides an exciting area in the generation of robust butanol production strategies. [ABSTRACT FROM AUTHOR]

n-Butanol is considered as the next-generation biofuel, because its physiochemical properties are very similar to fossil fuels and it could be produced by Clostridia under anaerobic culture. Due to the difficulties of strict anaerobic culture, a host which can be used with facultative environment was being searched for n-butanol production. As an alternative, Shewanella oneidensis MR-1, which is known as facultative bacteria, was selected as a host and studied. A plasmid containing adhE2 encoding alcohol dehydrogenase, various CoA transferases (ctfAB, atoAD, pct, and ACT), and acs encoding acetyl-CoA synthetase were introduced and examined to S. oneidensis MR-1 to produce n-butanol. As a result, ctfAB, acs, and adhE2 overexpression in S. oneidensis-pJM102 showed the highest n-butanol production in the presence of 2% of N-acetylglucosamine (NAG), 0.3% of butyrate, and 0.1 mM of IPTG for 96 h under microaerobic condition. When more NAG and butyrate were fed, n-butanol production was enhanced, producing up to 160 mg/L of n-butanol. When metal ions or extra electrons were added to S. oneidensis-pJM102 for n-butanol production, metal ion as electron acceptor or supply of extra electron showed no significant effect on n-butanol production. Overall, we made a newly engineered S. oneidensis that could utilize NAG and butyrate to produce n-butanol. It could be used in further microaerobic condition and electricity supply studies. [ABSTRACT FROM AUTHOR]

This report details our experimental study investigating particulate matter (PM) emissions from a diesel generator fueled with wood pyrolysis oil (WPO)-butanol blended fuel for electricity generation. Particle number-size distributions and PM mass concentrations from diesel, n-butanol, and WPO-butanol blended fuels were investigated via aerosol measurements using a fast mobility particle sizer and an aerosol monitor with three generator outputs (0, 3.3, and 6.6 kWe). For the n-butanol and WPO-blended fuels, the total number concentrations of exhaust particles were higher than that of conventional diesel combustion; however, the PM mass was observed to be nearly zero for all the engine operating conditions due to the higher number concentration in the nuclei mode. The morphology of the exhaust particles was investigated by analyzing transmission electron microscopy (TEM) micrographs. The morphology of the particles was drastically changed according to the test fuels and engine loads. Two types of particles were observed, including soot and coke shaped particles. These results were directly related to the immaturity of incipient soot particles due to the different physical properties and chemical compositions of the fuels. [ABSTRACT FROM AUTHOR]

Laminar flame speeds of n-butanol/air premixed flames were measured experimentally and numerically at elevated pressures and temperatures for a wide range of equivalence ratios. Laminar flame speeds were obtained experimentally from the temporal evaluation of the flame front of spherically outwardly propagating flames at zero stress rate. The shadowgraph technique was employed to gain optical access to the constant volume combustion chamber. Flame propagation images were captured by a high-speed camera and MATLAB codes were used to process the images and calculate laminar flame speeds. Flame speeds have been calculated numerically using CHEMKIN-Pro based on a short reaction mechanism for n-butanol oxidation, which was derived from a previously published full reaction mechanism. Numerical predictions were in qualitative agreement with experimental data. The effects of initial pressure and temperature elevation were analyzed. Also, the effect of simultaneous elevation of initial pressures and temperatures is documented. For all experimental conditions, the maximum flame speed was found at around equivalence ratio 1.1. In general, flame speeds decreased with the elevation of initial pressure and increased with initial temperature elevation. [ABSTRACT FROM AUTHOR]

Purpose: The production of ethyl acetate and n-butyl acetate was investigated through two different pathways: either by independent reactions or by coproduction. In the coproduction pathway, the n-butyl acetate was produced by reusing the by-products of the synthesis of ethyl acetate. This study provides a comparison of the environmental impacts of these two pathways using a life cycle assessment (LCA). A discussion about the use of LCA on chemicals and its challenges was also developed. Methods: Ethyl acetate and n-butyl acetate were synthesized with maximum respect to the principles of green chemistry (use of heterogeneous catalyst, energy savings, minimum steps). An innovative pathway was developed to avoid waste production, by reusing all the by-products of syntheses. After characterizing the feasibility of using these solvents in paint formulations, their potential impacts on the environment were evaluated through a cradle to gate analysis, up to the synthesis at laboratory scale. Most of the foreground data were directly collected with experimental trials. The background data that were not available in the Ecoinvent 3.1 database were estimated thanks to literature or proxys. Evaluations were then performed on the SimaPro 8.1.1 LCA software, using a derivative of ILCD 2011 1.05 as life cycle impact assessment methodology. Results and discussion: The coproduction of both acetates led to the synthesis of purified ethyl acetate (purity of 92.1% w/ w) and n-butyl acetate (purity of 97.1% w/ w), after distillation. These results were quite similar to those obtained when independent syntheses were carried out. On an environmental point of view, it was found that the reagents preparation was always the step of the process responsible of the majority of the environmental impacts. The comparison between independent syntheses and coproduction showed that recycling the acetic acid produced during the first esterification (ethyl acetate from ethanol and acetic anhydride) led to a decrease of the impacts from 5 to 23% for all the impact categories. Conclusions: This innovative coproduction of ethyl and n-butyl acetates led to interesting results from both a technical and environmental perspective, with a clear reduction of the environmental impacts. In a context of sustainable chemistry, this appears to be a very interesting way of production. Concerning the LCA of chemicals, a lot of work is still needed in order to improve the accuracy and the reliability of the assessment. [ABSTRACT FROM AUTHOR]

Substantial quantities of energy are required in conventional distillation columns applied in high-purity separation of close-boiling mixtures. To achieve energy saving of distillation, a novel different pressure thermally coupled distillation (DPTCD) was proposed for separating the close-boiling mixture of n-butanol and iso-butanol. Both this intensified energy integration technique and two other processes, namely conventional distillation (CD) and vapor recompression column (VRC), were simulated in process simulator Aspen Plus. The optimization was carried out to determine the optimal values of design and operating variables on the basis of minimizing energy consumption. Subsequently, the energy saving and economic efficiency of the DPTCD scheme were evaluated through the comparison with the other two processes. The results showed that, compared to the CD and VRC processes, the energy consumption of DPTCD process was decreased by 65.21 and 15.79%, respectively, and the total annual cost (TAC) of DPTCD process can be reduced by 33.75 and 10.46%. It demonstrated that DPTCD scheme was the most promising alternative to reduce the total energy consumption and TAC with high purity (99.1 wt%) n-butanol and iso-butanol products among these separation processes. [ABSTRACT FROM AUTHOR]

In this work, n-butyl levulinate a potential renewable chemical in the energy sector and in the field of fine chemical synthesis has been synthesized via alcoholysis of furfuryl alcohol in batch process at atmospheric pressure over SBA-16 supported tungstophosphoric acid (TPA) catalyst. In order to characterize and correlate the catalytic activity, the wet impregnated TPA/SBA-16 catalysts were subjected to the physico chemical characterization techniques such as X-ray diffraction, N-physisorption, SEM, TEM, FT-IR, NH-TPD and pyridine adsorbed FT-IR analysis. The retention of 3D mesoporous structure and TPA structure even after impregnation was confirmed by XRD and N-physisorption. The impregnation of TPA over SBA-16 creates the more number of available active acidic sites for the reactants. 25 wt% TPA/SBA-16 offers 97% selectivity to n-butyl levulinate with complete conversion of furfuryl alcohol in 3 h. Various reaction parameters were optimized to achieve the best catalytic activity. These results imply that the conversion of furfuryl alcohol to n-butyl levulinate go on with the formation of the intermediate 2-butoxymethylfuran. The recyclability of the catalyst and characterization of the spent catalyst was also studied. Graphical Abstract: SBA-16 supported TPA catalyst is effective in the conversion of furfuryl alcohol to n-butyl levulinate at atmospheric pressure. [ABSTRACT FROM AUTHOR]

Anther culture can be used as a powerful tool to produce doubled haploid (DH) lines in medicinal plants, thus accelerating breeding programs. In the particular case of borage ( Borago officinalis L.), a method to produce DH plants has not been yet published. In this work we evaluated the effect of different culture media and of different chemical (colchicine and n-butanol) and physical stresses (centrifugation and electroporation) on androgenesis induction and plant regeneration in borage anther cultures. We found that the highest response can be obtained with culture medium containing B salts and NLN vitamins, the addition of 200 mg/l colchicine during 4 days, a pretreatment of anthers with 0.2% n-butanol for 5 h, or the application to anthers of single physical stresses (either centrifugation at 300× g or a 100 V electrical shock, but not combined). This is the first report on the production of DH plants in borage. Together, the results presented hereby can be used as a basic framework for large-scale generation of DH plants in this important medicinal species. [ABSTRACT FROM AUTHOR]

This study experimentally focuses on finding the optimum blend ratio for Direct injection (D.I) diesel engine fuelled with mahua oildiesel and n-butanol- diesel without any modifications in the engine. Test fuels were prepared by choosing 8 different concentrations as B10 (10 % Biodiesel and 90 % Diesel), B20 (20 % Biodiesel and 80 % Diesel), B30 (30 % Biodiesel and 70 % Diesel), B40 (40 % Biodiesel and 60 % Diesel), BU10 (10 % n-butanol and 90 % Diesel), BU20 (20 % n-butanol and 80 % Diesel), BU30 (30 % n-butanol and 70 % Diesel), BU40 (40 % n-butanol and 60 % Diesel). Experiments were performed at constant speed and variable loads at standard injection timing of 23 Crank angle degree BTDC and standard compression ratio of 16.5:1 to determine the engine performance indicators and exhaust gas emissions such as carbon monoxide, carbon dioxide, hydrocarbon, soot content and oxides of nitrogen. The optimum blend ratio for mahua biodiesel- diesel blend and n-butanol- diesel blend were determined and compared on eco-friendly and economical basis to gain the suitable substitute fuel. The result showed that Mahua biodiesel blend is eco-friendly and economically apt alternative fuel for diesel. [ABSTRACT FROM AUTHOR]

Biofuel alcohols have severe consequences on the microbial hosts used in their biosynthesis, which limits the productivity of the bioconversion. The cell envelope is one of the most strongly affected structures, in particular, as the external concentration of biofuels rises during biosynthesis. Damage to the cell envelope can have severe consequences, such as impairment of transport into and out of the cell; however, the nature of butanol-induced envelope damage has not been well characterized. In the present study, the effects of n-butanol on the cell envelope of Escherichia coli were investigated. Using enzyme and fluorescence-based assays, we observed that 1 % v/ v n-butanol resulted in the release of lipopolysaccharides from the outer membrane of E. coli and caused 'leakiness' in both outer and inner membranes. Higher concentrations of n-butanol, within the range of 2-10 % ( v/ v), resulted in inner membrane protrusion through the peptidoglycan observed by characteristic blebs. The findings suggest that strategies for rational engineering of butanol-tolerant bacterial strains should take into account all components of the cell envelope. [ABSTRACT FROM AUTHOR]

Although oxygenated fuel additives are effective in reducing soot emissions, the extent to which molecular structure of the oxygenate plays a role in soot reduction has remained unclear and controversial. To gain a deeper insight in this field, a detailed chemical kinetic modeling approach was used to examine the phenomenon of suppression of sooting by the addition of oxygenated hydrocarbon species to the fuel. For this task, the PREMIX code in conjunction with Chemkin II and models resulting from the merging of validated kinetic schemes describing the oxidation of the components of the n-butanol-benzene mixtures were used to investigate the effect of n-butanol addition on the formation−depletion of acetylene recognized as soot precursor in flames under fuel-rich conditions. The first part of this study treats the dependence of the soot precursor amounts on n-butanol percentage in the fuel mixture, whereas the second part defines the key reaction mechanisms responsible for the observed reduction in CH and consequently in polycyclic aromatic hydrocarbons and soot amounts induced by the oxygenate additive. The principal objective of the current study was to obtain fundamental understanding of the mechanisms through which the oxygenate compound affects the soot precursor amounts. The modeling results indicated that there was a dramatic decrease in the acetylene peak height with the addition of the oxygenated addtitive. This finding was found to be due to the increase in the CH consumption rates induced by n-butanol addition. Finally, the modeling results provided evidence that n-butanol played a role in changing acetylene formation mechanism by enhancing the role of CHP, CH and aCH and by eliminating the role of CH, CH, CH, HCCCCH, CH, CHO, CH, CHCHCHO, HCO and CH. [ABSTRACT FROM AUTHOR]

The diminishing oil reserves, environmental degradation and increasing prices of petroleum-derived fuels have necessitated the search for cleaner and renewable alternative fuels, such as biodiesel. In this context, the objective of this research is to evaluate the suitability of n-butanol as a blending stock in jatropha methyl ester (JME) for use in a C.I. engine as substitute of diesel and to evaluate the performance and emission characteristics of an unmodified diesel engine. Three blends of n-butanol-JME (5, 10 and 20 % n-butanol with JME on volumetric basis) were prepared. Fuel properties including calorific value, kinematic viscosity and density of blends were found to decrease with increasing percentage of n-butanol in JME. The brake thermal efficiency of the engine was higher for blends and was found to increase by increasing the percentage of n-butanol in the blends. Carbon monoxide (CO), the oxides of nitrogen (NO) and smoke opacity of blends were found lower than JME during the whole experimental range. However, unburnt hydrocarbon (HC) emission was found to have slightly increased. The experimental results suggested that the engine performance had improved and emissions have significantly reduced (except HC) with blends of n-butanol and JME in comparison with neat JME. Therefore, it could be concluded that n-butanol is a potential alternative fuel to be blended with JME for diesel engine application. [ABSTRACT FROM AUTHOR]

Density and surface tension have been measured for mixtures of biodiesel+ n-butanol, biodiesel+diesel, and diesel+ n-butanol over the entire concentration range at 283.15 K and 293.15 K and atmospheric pressure, with the combined expanded uncertainties of 1.32 kg·m and 1%, receptively. Densities were determined by a single-sinker densimeter; surface tensions were measured using the surface laser light scattering method. The experimental data showed that densities and surface tensions decreased as temperature increased. The excess surface tensions and excess densities were all negative, and further fitted to the Redlich-Kister equation. [ABSTRACT FROM AUTHOR]

A global kinetic model was constructed from the combination of two existing and broadly validated kinetic schemes for benzene and butanol. Then the combined model, which was able to predict the combustion behavior of benzene-butanol fuel mixtures, was implemented in the PREMIX code in conjunction with CHEMKIN II in order to investigate the effect of n-butanol addition on the formation-depletion of propargil radical CH, which is known to be soot precursor, in fuel-rich n-butanol-benzene flames. It was treated the dependence of the soot precursor amounts on n-butanol percentage in the fuel mixture. Then was considered the causes of the variation of this species mole fractions with benzene replacement percentage by oxygenate additive. The principal objective of the current study was to obtain fundamental understanding of the mechanisms through which the oxygenate compound affects the soot precursor amounts. It was found that n-butanol-benzene fuel mixture displayed lower propargyl radical concentrations as compared to the pure benzene flame. [ABSTRACT FROM AUTHOR]

We investigate the emission and combustion characteristics of a biomass-based fuel that is primarily comprised of two biofuels, namely, wood pyrolysis oil (WPO) and n-butanol in a DI diesel engine. WPO has been of interest as an alternative fuel to conventional fossil fuels in several countries. The use of WPO in conventional internal combustion engines, however, requires modifications of their fuel supply systems due to its poor fuel properties of high viscosity, high water content, and low cetane number. In addition, since WPO is chemically unstable, gummy polymers are spontaneously generated, increasing the viscosity of the fuel. In the present study, it is shown that n-butanol plays an important role in facilitating the use of WPO in an internal combustion engine. Principally, n-butanol can be mixed with WPO without any phase separation. Additionally, n-butanol has a viscosity of 3.1 cSt that is similar to the viscosity value of 2.7 cSt for diesel, and can effectively lower the viscosity of the blended fuel. As an organic solvent, n-butanol is capable of dissolving solid particles existing in WPO and suppressing polymerization. In order to achieve a stable combustion of WPO-butanol blended fuels, we introduce a high compression ratio diesel engine. Experimental results show that the combustion of WPO-butanol blended fuels yields lower particulate matter emissions than diesel fuel combustion. [ABSTRACT FROM AUTHOR]

The improvement of androgenic induction efficiency of anther cultures is an important goal for plant biotechnology. Although n-butanol has been proven to enhance the androgenic induction, the structural background of this effect has not been investigated in detail. In the present study, the cytological and ultrastructural alterations triggered by two treatments that improve androgenic induction, n-butanol (0.2 % n-butanol for 6 h) and cold pretreatment (7 °C for 10 days) were studied in maize anther cultures. Both treatments increased the frequency of responding microspores, and the highest embryo yield (20.9 embryos per 100 plated anthers compared to 0.5/100 anthers in control) was achieved when a combination of both treatments was applied. To study the effect of the treatments on the cytoskeleton, we labeled microtubules using indirect immunofluorescence and actin filaments by rhodamine phalloidin. Cold pretreatment increased the quantity of actin filaments, whereas the microtubule network remained unaffected. In contrast, n-butanol treatment triggered the reversible depolymerization of microtubules, without having any effect on the actin network. Transmission electron microscopy revealed that n-butanol induced the formation of irregular cell walls. Autophagy-related structures were present during the early development of embryogenic microspores following both treatments, but autophagy was only sustained after fourteen days in microspore-derived structures treated with n-butanol. The results support the concept that the androgenic developmental switch is assisted by cytoskeletal rearrangements, which may facilitate androgenic induction through the promotion of symmetric divisions. The longer duration of autophagic processes may also play a role in the elevated embryo induction after n-butanol treatment. [ABSTRACT FROM AUTHOR]

Strain tolerance to toxic metabolites remains an important issue in the production of biofuels. Here we examined the impact of overexpressing the heterologous groESL chaperone from Clostridium acetobutylicum to enhance the tolerance of Escherichia coli against several stressors. Strain tolerance was identified using strain maximum specific growth rate (μ) and strain growth after a period of solvent exposure. In comparison with control strain, the groESL overexpressing strain yielded a 27% increase in growth under 0.8% (v/v) butanol, a 9% increase under 1% (v/v) butanol, and a 64% increase under 1.75 (g/l) acetate. Moreover, after 10 h, groESL overexpression resulted in increase in relative tolerance of 58% compared with control strain under 0.8% (v/v) butanol, 56% increase under 1% (v/v) butanol, 42% increase under 1% (v/v) isobutanol, 36% increase under 4% (v/v) ethanol, 58% increase under 1.75 (g/l) acetate. These data demonstrate that overexpression of the groESL from C. acetobutylicum in E. coli increased tolerance to several stressors. Solvent tolerant strain of E. coli was developed to be used as a basic strain for biofuel production. [ABSTRACT FROM AUTHOR]

In this study, a three step purification of alkaline phosphatase from non-pasteurized milk has been described. It included cream extraction, n-butanol treatment and acetone precipitation. Different parameters such as buffer concentration, temperature, pH, substrate concentration, acetone and n-butanol treatment were optimized to maximize the enzyme activity. The enzyme was fruitfully purified up to homogeneity from the milk, with percentage recovery and fold purification of 56.17 and 17.67 respectively. The kinetic parameters were determined to be 0.927 mM (K) and 55.86 μM/min (V), with specific activity of 11.31 U/mg. Other optimized parameters were estimated as a buffer concentration of 0.5 M with pH 9.0, temperature optima at 37 °C, with n-butanol and acetone concentration of 20 % ( v/ v) and 50 % ( v/ v) respectively. This approach provides a simple and effective method for the purification of alkaline phosphatase from non-pasteurized milk. [ABSTRACT FROM AUTHOR]

Odorant pens are used by medical practitioners and researchers to assess olfactory dysfunction. Despite their routine use, there are currently no data on the gas-phase odorant concentrations released from the pen tips or whether these concentrations scale linearly with the aqueous-phase concentrations inside the pens. The commercially available Sniffin' Sticks odor threshold test containing n-butanol was chosen for evaluation. The gas-phase concentration of n-butanol at the tip of each pen was measured directly in a new set of pens via proton-transfer-reaction mass spectrometry (PTR-MS). Measurements were additionally made on the same pens after 6 months and two older pen sets, namely a 3-year-old (used) and 4-year-old (new) set. Furthermore, application-related tests were made to determine the performance of the pens during routine use and under stress. These data demonstrate that the gas-phase n-butanol concentrations of the threshold pens are linear over the entire set, both for brand-new pens and 6 months later; this reflects the expected performance that was previously only assumed. Furthermore, the application-simulation tests demonstrated a good performance of the pens when used according to their intended protocol. Measurements of the older pen sets suggest that storage conditions are more critical than usage for pen stability. The present findings confirm that the n-butanol odorant pens are an appropriate tool for threshold testing, provided they are stored and handled correctly. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Doubled haploid (DH) production is an efficient tool in barley breeding, but efficiency of DH methods is not consistent. Hence, the aim of this study was to study the effect of n-butanol application on DH barley plant production efficiency. Five elite cultivars of barley and thirteen breeding crosses with different microspore embryogenesis capacities were selected for n-butanol application in anther and isolated microspore cultures. Application of 0.1 % n-butanol after a mannitol stress treatment in anther culture significantly increased the number of embryos (up to almost twice) and green plants (from 1.7 to 3 times) in three low-responding cultivars: Albacete, Astoria and Majestic. No significant differences on microspore embryogenesis efficiency were observed in medium and high responding cultivars. The application of n-butanol treatment to isolated microspores from cold treated spikes in thirteen spring breeding crosses with a low or very low androgenetic response did not have a significant effect on the overall number of green plants. Nevertheless, an increase in the number of green plants was observed when 0.2 % n-butanol was applied in four out of seven low-responding crosses. Therefore, application of n-butanol could be routinely applied to anther cultures using mannitol treatment, in low-responding material. However, further studies are needed to determine optimal conditions in protocols using cold treatment and isolated microspore cultures. [ABSTRACT FROM AUTHOR]

Absorption bands corresponding to all types of hydroxyl associates [ν = 3476 cm (OH...OH); ν = 3472 cm (OH...N); and ν = 3457 cm (OH...O)] were assigned using IR spectroscopy in CHCl and n-butanol and its mixtures with various proton acceptors (THF, hexylazide, azide-containing oxetane monomers). The order of concentrations for these associates was $ {C_{{\mathrm{OH}\ldots \mathrm{O}\mathrm{H}}}}\ll {C_{{\mathrm{OH}\ldots {{\mathrm{N}}_3}}}}\ll {C_{{\mathrm{OH}\ldots \mathrm{O}}}} $. Equilibrium formation constants were estimated quantitatively. The proton-acceptor abilities of the studied additives were established. [ABSTRACT FROM AUTHOR]

Mesoporous Si-MCM-41 and Al-MCM-41 (Si/Al = 100) materials were synthesized via a hydrothermal method. Three different ratios (10, 20 and 30 wt%) of heteropoly tungstic acid (HPWA) was loaded on Si-MCM-41 by wet impregnation techniques. The characteristic structural features of the prepared materials were studied by various physico-chemical techniques such as X-ray diffraction (XRD), Nitrogen physisorption (BET), temperature programmed desorption of ammonia (TPD) and transmission electron microscopy (TEM). Transesterification of diethyl malonate (DEM) with n-butanol under autogeneous conditions in a temperature range from 50 to 125 °C was selected as the test reaction for the as synthesized materials. The reactants were fed with various mole ratios in order to determine the optimal feed composition leading to maximum yields of transesterified products. The results indicated that the conversion of diethylmalonate depends on the HPWA concentration on the support, temperature, reaction time and mole ratio of the reactants. Further, the catalytic efficiency of HPWA/MCM-41 was compared with that of Al-MCM-41. The solid acid HPWA/MCM-41 catalysts have several advantages in comparison to conventional mineral acid catalysts which are heterogeneous, eco-friendly, highly active and selective in the formation of transesters. [ABSTRACT FROM AUTHOR]