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Reactions on the surface of catalysts are rather complex, and many possible reaction pathways and intermediates are involved. We here propose a method that is able to automatically generate a catalytic reaction network and identify the preferred reaction pathway with determined uncertainty. Taking syngas conversion to ethanol on Rh(111) as an example, a reaction network consisting of 95 elementary steps was generated. Using energies calculated with an ensemble of 2000 functionals, the occurrence frequency of different ethanol formation pathways was obtained through pruning of the reaction network with mean-field microkinetic modeling. We found that CHCO is the most important reaction intermediate for ethanol formation with the highest confidence, even at varied temperatures and pressures. The transition state of CH3CH2O hydrogenation, i.e. CH3CH2O-H, possesses the highest possibility to be rate-controlling. CO has the highest possibility to be the surface dominant species at all the temperatures and pressures considered. The method developed in the current work substantially reduces the complexity of identifying the mechanism of catalytic reactions and shows great potential in expediting future catalyst design.

OBJECTIVE To determine the association of temperature, time duration, and preservatives with ethanol neo-genesis in postmortem whole blood samples. STUDY DESIGN Observational cross-sectional study. PLACE AND DURATION OF STUDY Department of Chemical Pathology and Toxicology, Armed Forces Institute of Pathology, Rawalpindi, in collaboration with Combined Military Hospital, Rawalpindi from August 2020 to January 2021. METHODOLOGY Whole blood samples were obtained from cardiac chamber of an autopsy case with aseptic measures and were drawn into six tubes (3 x EDTA tubes and 3 x NaF tubes). These six tubes were stored at 4˚C, 25˚C, and 37˚C. All samples were analysed along with internal standard, on head space gas-chromatography on Day-0, Day-07, Day-14, Day-21, and Day-28 of sampling. RESULTS A total of 60 samples out of 10 autopsies, were analysed. Blood alcohol concentrations of all samples were negative on 1st day (Day-0) of analysis. Samples stored at 4˚C did not produce any ethanol at any day of analysis, regardless of preservatives used. Neo-ethanol levels of blood samples stored in EDTA preservative were significantly raised (p

Ethanol is one of the most commonly used and abused substances worldwide. Identifying whether the source of ethanol detected in corpses is antemortem ingestion or postmortem generation is especially important for determining the cause of death, which remains a vibrant field of research. During the synthesis of ethanol in the putrefaction process of corpses, other small molecules such as acetaldehyde and n-propanol could also be produced. According to our prospective statistical analysis based on authentic samples from forensic cases, it is rational to suspect ethanol generation after death when the concentration of acetaldehyde detected in blood exceeds 0.014 g/dL. Through in vitro simulation experiments, in addition to confirming that ethyl glucuronide and ethyl sulfate are the reliable biomarkers of antemortem ingestion of ethanol, we propose that acetaldehyde is far more sensitive than n-propanol as a potential marker in the blood of corpses for postmortem ethanol formation.

In this work the influence of acerola (Malpighiae marginata DC) pulp, at concentrations of 0, 10, 15, 25 and 30%, on mead production by Saccharomyces cerevisiae AWRI 796 was evaluated. A novel approach based on cell growth to obtain high accuracy fits for the data and to estimate optimization parameters such as Gibbs free energy was used. Fermentation was done using 107 cells/mL at pH 5.0 and 30 °C for up to 288 h. The addition of increasing concentrations of acerola pulp progressively enhanced the cell growth, with the highest cell concentration reached being ∼2.09 × 108 cells/mL. Under these conditions, the lowest Gibbs free energy of growth was −4.81 kJ/mol after fermentation for 288 h at a pulp concentration of ∼18%. The velocity of substrate consumption was −14 × 10−3 A.U./h whereas the velocity of ethanol formation was 17 × 10−3 A.U./h with ethanol production of 15.2% v/v or 120.1 g/L.

Remediation of electronic gas CF4 using commercially available technologies results in another kind of greenhouse gas and corrosive side products. This investigation aimed to develop CF4 removal at room temperature with formation of useful product by attempting an electrogenerated Cu1+[Ni2+(CN)4]1− mediator. The initial electrolysis of the bimetallic complex at the anodized Ti cathode demonstrated Cu1+[Ni2+(CN)4]1− formation, which was confirmed by additional electron spin resonance results. The degradation of CF4 followed mediated electrochemical reduction by electrogenerated Cu1+[Ni2+(CN)4]1−. The removal efficiency of CF4 of 95% was achieved by this electroscrubbing process at room temperature. The spectral results of online and offline Fourier transform infrared analyzer, either in gas or in solution phase, demonstrated that the product formed during the removal of CF4 by electrogenerated Cu1+[Ni2+(CN)4]1− by electroscrubbing was ethanol (CH3CH2OH), with a small amount of trifluoroethane (CF3CH3) intermediate.

The degradation of CF4 gas using existing technologies produces other types of greenhouse gas (CO2) and corrosive side products. The main aim of this study is to degrade CF4 gas at room temperature into useful products without producing corrosive side products by mediated electrochemical reduction (MER) process using an electrogenerated Cu1+[Ni2+(CN)4]1− mediator. Initial studies on the electrolytic reduction of the hetero-bimetallic complex in catholyte solution at anodized Ti cathode was monitored by oxidation/reduction potential (ORP) variation whether the Cu2+ or Ni2+ was reduced in the Cu2+[Ni2+(CN)4] and confirmed by electron spin resonance (ESR) spectroscopy the Cu1+[Ni2+(CN)4]1− formation. The concentration variation of Cu1+[Ni2+(CN)4]1− during CF4 injection demonstrated the degradation of CF4 followed the MER by electrogenerated Cu1+[Ni2+(CN)4]1−. Maximum removal efficiency of CF4 using electroscrubbing process was 96% at room temperature. Through the variation in gas phase parameters, the gas phase mass transfer coefficient was calculated that can facilitate scale up the developed process. Fourier transform infrared spectroscopy analysis in both the gas and solution phases showed that CH3CH2OH was the main product that formed during the removal of CF4 by electrogenerated Cu1+[Ni2+(CN)4]1− at electroscrubber along with a small amount of CF3CH3 intermediate. Importantly, this mechanism also avoided formation of the corrosive product HF.

Density functional theory calculations have been employed to investigate the effect of promoter Co on C2 oxygenate formation from syngas on pure Cu(100) and two kinds of Co-Cu bimetallic surfaces. Based on the results of previous studies that CH3O is a key intermediate in ethanol formation on Cu catalyst, five reactions starting from CH3O were taken into consideration. Different from the results on Cu(100) that CH3OH is the most favorable product on pure Co sites, CH3 formation is more favorable both kinetically and thermodynamically than CH3OH formation, which leads to more CH3 available for CHO insertion to form C2 oxygenates. On the other hand, Co-Cu bimetallic sites can facilitate CHO insertion into CH3 energetically, which is favorable for carbon chain growth. And the addition of Co can make the barrier of CH3 hydrogenation and CH3 coupling to CH4 and CH3CH3 higher, making CH3CHO much more selective than hydrocarbons. In conclusion, by introducing Co into Cu catalyst, the productivity and selectivity of C2 oxygenate precursor of ethanol can be effectively improved. The optimum Co-Cu catalyst should contain Cu ensembles and Co ensembles with proper sizes, and offer enough Co-Cu bimetallic sites at the same time.

A Fe-based catalyst exhibits extremely high selectivity (89.6%) besides excellent catalytic activity in gas-phase dimethyl oxalate hydrogenation. The ethanol formation occurs via hydrogenation of methyl acetate instead of ethylene glycol over the active species Fe5C2.

This paper improves the tetraethoxysilane (TEOS) oxidation mechanism proposed by Nurkowski et al. (2015) [17] by refining the rate parameters of the key reaction channels in the mechanism. A skeletal version of the mechanism is proposed for hydrogen–oxygen environment. The rates of ethylene-loss from (tetra-, tri-, di- and dimethyldi-) ethoxysilane are computed using transition state theory. The energetics of the main pathways are refined by performing detailed ab initio calculations using the CBS-Q technique. An analysis of ethanol formation via silicates is also performed resulting in the addition of 27 new silica species to the model. Thermodynamic properties for these species are calculated via the balanced reactions method. Reasonably good agreement between the improved model and available experimental data is observed. The subsequent elimination of unimportant species and reactions is achieved via a three-stage reduction procedure. The first and second stages involve the Direct Relation Graph with Error Propagation (DRGEP) method, whereas the third stage analyses rate of progress of each reaction. The investigated conditions are taken from the experimental studies of TEOS oxidation in oxygen–hydrogen flames. The final skeletal mechanism comprises 70 species and 457 reactions and retains good reproduction of the key model properties across the chosen operating conditions as compared to the full mechanism.

The influence of short-term storage in air atmosphere and modified atmosphere (MA) conditions obtained by different film perforations and storage conditions on carrot root quality was studied. The carrots were stored at temperature conditions simulating the commercial distribution chain. The quality was evaluated using chemical analyses, descriptive sensory analyses and evaluation of decay at the end of storage. One kilogram of carrots were packaged at a commercial packing house in pouches with (1) 13 laser perforations, (2) 11 warm needle perforations and 3) approximately 560 warm needle perforations per 10 × 10 cm (“bread pouch”). The packages were stored at optimal (chill) storage conditions of 4 °C for 6 d followed by 6 °C for 9 d, or at an abusive temperatures (common retail storage) conditions of 4 °C for 3 d, 20 °C for 3 d and 6 °C for 9 d. The highest weight loss during storage was observed for the “bread” perforated packages stored at retail conditions (2.3%) and at chill conditions (1.4%). The weight loss was below 0.34% for all the other packages with different perforation and storage combinations. The gas concentration in the needle perforated packages was close to air both at chill and retail storage conditions. In laser perforated packages at chill conditions, the O 2 -concentration stabilised at 12–13 kPa and the CO 2 -concentration at 9–10 kPa, whereas at abused temperature the O 2 concentration decreased to 4 kPa the last day of storage at 20 °C (day 6) and CO 2 concentration approximately at 32 kPa at day 6. The low O 2 concentration and high CO 2 concentration in laser perforated packages stored at retail conditions and the high ethanol content measured in these carrots could indicate anaerobic respiration. These carrots also had significantly higher scores for ethanol odour and flavour. The carrots in laser and needle perforated packages stored at chill conditions had the highest scores for terpene odour and flavour. Percentage diseased carrots were highest in the laser perforated packages stored at retail conditions. The experiment showed that the overall carrot quality was best maintained in needle perforated packages with a gas atmosphere close to air, giving no major weight loss, no ethanol formation and the lowest incidences of storage diseases at both chill and retail conditions.

This study investigates the simultaneous saccharification and fermentation (SSF) process for bioethanol production from corn cobs with prehydrolysis (PSSF) and without prehydrolysis (OSSF). Two response surface models were developed with high coefficients of determination (>0.90). Process optimization gave high bioethanol concentrations and bioethanol conversions for the PSSF (36.92 ± 1.34 g/L and 62.36 ± 2.27%) and OSSF (35.04 ± 0.170 g/L and 58.13 ± 0.283%) models respectively. Additionally, the logistic and modified Gompertz models were used to study the kinetics of microbial cell growth and ethanol formation under microaerophilic and anaerobic conditions. Cell growth in the OSSFmicroaerophilic process gave the highest maximum specific growth rate (µmax) of 0.274 h−1. The PSSFmicroaerophilic bioprocess gave the highest potential maximum bioethanol concentration (Pm) (42.24 g/L). This study demonstrated that microaerophilic rather than anaerobic culture conditions enhanced cell growth and bioethanol production, and that additional prehydrolysis steps do not significantly impact on the bioethanol concentration and conversion in SSF process.

Low cost Cu-based catalysts have became an attractive option in catalyzing ethanol formation from syngas (2CO + 4H 2 = C 2 H 5 OH + H 2 O). In this study, the complex mechanism of ethanol formation from syngas on Cu(1 0 0) surface has been investigated using density functional theory (DFT) calculations together with periodic slab models, in which all possible formation pathways of CH x ( x = 1–3) and C 2 oxygenates of ethanol precursor, as well as the hydrogenation of C 2 oxygenates to ethanol have been considered. Our results suggest that ethanol formation starts with CO hydrogenation to CHO, subsequently, CHO is further hydrogenated to CH 3 O via CH 2 O intermediate, CH 3 O is eventually hydrogenated to CH 3 OH; alternatively, CH 3 O dissociation with hydrogen-assisted can also produce CH 3 ; then, CHO insertion into CH 3 can lead to the key intermediate CH 3 CHO, which is successively hydrogenated to ethanol via CH 3 CH 2 O intermediates; moreover, among all reactions related to CH 3 species, CHO insertion into CH 3 to CH 3 CHO is the most favorable reaction, which is responsible for C 2 oxygenates formation. In the overall process of ethanol synthesis, CH 3 OH is more easily formed than CH 3 , and ethanol formation is controlled by CH 3 formation, which means that the preferable CH 3 OH formation rather than CH 3 is responsible for the low productivity and selectivity of ethanol. Therefore, aiming to obtain high productivity and selectivity to ethanol from syngas on Cu catalyst, we need to selectively modify Cu catalyst by using the promoters and/or supports, which should be able to boost CH 3 formation and/or suppress CH 3 OH formation, this result can be applied to selectively modify and develop the novel Cu-based catalyst towards ethanol formation from syngas.

Density functional theory calculations have been employed to investigate the effect of promoter Mn on ethanol formation from syngas on a Mn-promoted MnCu(211) surface. Our results show that CO + 3H → CHO + 2H → CH2O + H → CH3O is an optimal pathway for the overall CO conversion. Starting with CH3O, CH3 is formed via CH3O → CH3 + O. Then, CHO insertion into CH3 can form CH3CHO, and further, CH3CHO is successively hydrogenated to ethanol via CH3CH2O intermediate. Meanwhile, CH3OH is formed via CH3O + H → CH3OH. Compared to the pure Cu(211) surface, CH3 formation is found to be energetically compatible with CH3OH formation on the MnCu(211) surface, which can lead to more CH3 sources and less CH3OH; thus, the productivity and selectivity of ethanol can be improved. On the other hand, starting from CH3, the MnCu(211) surface is more favorable for CHO insertion into CH3 to CH3CHO in comparison with CH3 hydrogenation, dissociation and coupling to CH4, CH2, and C2H6 due to their high activation barriers; namely, ...

Batch cultures of C. utilis CBS 621 were carried out in a pressurized reactor under increased air pressure up to 6 bar. The effect of total air pressure was also investigated in a high cell density fed-batch culture, raising the total air pressure from 1 bar to 12 bar. The results showed that the rise of air pressure, for both operation modes, led to a substantial enhancement of biomass production. Moreover, ethanol formation was significantly reduced at 6 bar and 12 bar air pressure, respectively for batch and fed-batch processes. A method using automatic image analysis for classification of C. utilis cells based on their morphology was developed and applied to experimental data. Morphological parameters such as single and budding cells, cell size and elongation factor, were analyzed to assess the pressure effect on yeast culture. No significant differences were observed in cell size distribution and yeast cells retained the typical oval form, even at 12 bar air pressure. In what biological aspects are concerned, it is possible to state that C. utilis CBS 621 can cope with hyperbaric stress, meaning that the use of increased air pressure is a suitable method for oxygenation enhancement of high density cultures of this strain., The authors acknowledge the financial support provided by "Fundacao para a Ciencia e Tecnologia", Portugal.

After moisture, fat is the major constituent of table olives. However, scarce studies have been carried out to determine the influence of microorganisms and type of processing on the modification of their quality indexes. The present survey studies the influence of lipolytic (Candida boidinii TOMC Y5 and Wickerhamomyces anomalus TOMC Y10) and nonlipolytic (Debaryomyces etchellsii TOMC Y9 and Pichia galeiformis TOMC Y27) yeasts on the oil quality indexes of Manzanilla and Hojiblanca green fruits processed as directly brined and lye-treated table olives. Overall, the inocula scarcely used available sugars, except the lipolytic C. boidinii strain in lye-treated olives. Acetic acid production was limited in all conditions, except for the D. etchellsii strain in directly brined Manzanilla fruits. Ethanol formation was also reduced, although the W. anomalus (in both types of elaboration) and the C. boidinii (in lye-treated olives) strains produced significantly higher proportions. Apparently, changes in the oil quality indexes of processed olives were not related to the presence of yeasts, and hence, could have been caused by the endogenous activity of the fruits. A principal component analysis using the microbiological, physicochemical, and oil quality data supported this hypothesis, grouping treatments according to olive variety and type of elaboration, while segregation due to yeast inocula was not observed.

Saccharomyces cerevisiae is a popular expression system for recombinant proteins. In most cases, production processes are performed as carbon-limited fed-batch cultures to avoid aerobic ethanol formation. Especially for constitutive expression systems, the specific product formation rate depends on the specific growth rate. The development of optimal feeding strategies strongly depends on laboratory scale cultivations, which are time and resource consuming, especially when continuous experiments are carried out. It is therefore beneficial for accelerated process development to look at alternatives. In this study, S. cerevisiae AH22 secreting a heterologous endo-polygalacturonase (EPG) was characterized in microwell plates with an enzyme-based fed-batch medium. Through variation of the glucose release rate, different growth profiles were established and the impact on EPG secretion was analyzed. Product formation rates of 200- 400 U (gx h)−1 were determined. As a reference, bioreactor experiments using the change-stat cultivation technique were performed. The growth-dependent product formation was analyzed over dilution rates of D = 0.01 – 0.35 with smooth change of D at a rate of 0.003 h−2. EPG production was found to be comparable with a qp of 400 U (gx h)−1 at D = 0.27 h−1. The presented results indicate that parallel miniaturized fed-batch cultures can be applied to determine product formation profiles of putative production strains. With further automation and parallelization of the concept, strain characterization can be performed in shorter time. This article is protected by copyright. All rights reserved

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A new biocatalyst was prepared by immobilization of Saccharomyces cerevisiae AXAZ-1 yeast cells on whole corn grains. This biocatalyst was used for 30 repeated batch fermentations of glucose and grape musts at various temperatures. The biocatalyst retained its operational stability for a long period and it proved able to produce dry wines of fine clarity, even at extremely low temperatures (5 °C). The produced wines were analyzed for volatile byproducts by GC and GC–MS. The results showed an increase in the number and amount of esters produced when immobilized cells were used. In addition, an increase in the percentages of esters and a decrease in those of alcohols with the decrease of fermentation temperature were observed. Finally a model, appropriate for describing sugar consumption and the simultaneous ethanol formation by immobilized cells, was proposed. The results of this model fit almost perfectly with the experimental data.

The increasing interest of consumers in health and alcohol abuse issues motivates breweries to expand the assortment of products with low alcohol content. The goal of producing beers with low alcohol content can be achieved by two main strategies; namely by gentle removal of alcohol from regular beer and by limited ethanol formation during the beer fermentation. Within these two basic strategies, there are a number of techniques that vary in performance, efficiency and usability. This paper presents an overview and comparison of these techniques and provides an evaluation of sensorial properties of low-alcohol and an alcohol-free beer produced as well as suggests possibilities for their additional improvement.

The visible-light responsive photocatalyst BiVO4 was synthesized, and its photocatalytic reduction of CO2 in water was examined. Our study shows the selective formation of ethanol under the condition of high intensity visible-light irradiation, and suggests that intense irradiation generates a large number of C1 intermediate species anchored on the surface of BiVO4, which dimerize to form ethanol. For the photocatalytic reduction of CO2 into ethanol, monoclinic BiVO4 is more efficient than tetragonal BiVO4.

Summary A permeable membrane coating can be produced on fruit surfaces by dipping in an aqueous dispersion of Pro-long, a mixture of sucrose esters of fatty acids and the sodium salt of carboxymethylcellulose. Mangoes (Mangifera indica L. cv. Julie) were treated with 0.75 and 1.0% w/v aqueous suspensions of Pro-long and stored at 252°C/85–95% RH. Treatment with 0.75% Pro-long significantly increased the storage life of mangoes, retarding ripening and reducing weight loss, without adversely affecting the sensory quality of the fruit. Treatment at 1% resulted in increased ethanol formation in the pulp of some mangoes.

Metabolic enzymes are very specific. However, most of them show weak side activities toward compounds that are structurally related to their physiological substrates, thereby producing side products that may be toxic. In some cases, 'metabolite repair enzymes' eliminating side products have been identified. We show that mammalian glyceraldehyde 3-phosphate dehydrogenase and pyruvate kinase, two core glycolytic enzymes, produce 4-phosphoerythronate and 2-phospho-L-lactate, respectively. 4-Phosphoerythronate strongly inhibits an enzyme of the pentose phosphate pathway, whereas 2-phospho-L-lactate inhibits the enzyme producing the glycolytic activator fructose 2,6-bisphosphate. We discovered that a single, widely conserved enzyme, known as phosphoglycolate phosphatase (PGP) in mammals, dephosphorylates both 4-phosphoerythronate and 2-phospho-L-lactate, thereby preventing a block in the pentose phosphate pathway and glycolysis. Its yeast ortholog, Pho13, similarly dephosphorylates 4-phosphoerythronate and 2-phosphoglycolate, a side product of pyruvate kinase. Our work illustrates how metabolite repair enzymes can make up for the limited specificity of metabolic enzymes and permit high flux in central metabolic pathways.

During the investigation of aviation accidents, postmortem samples obtained from fatal accident victims are submitted to the FAA's Civil Aerospace Medical Institute (CAMI) for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Many species of bacteria, yeast, and fungi have the ability to produce ethanol and other volatile organic compounds in postmortem specimens. The potential for postmortem ethanol formation complicates the interpretation of ethanol-positive results from accident victims. Therefore, the prevention of ethanol formation at all steps following specimen collection is a priority. Sodium fluoride is the most commonly used preservative for postmortem specimens. Several studies have been published detailing the effectiveness of sodium fluoride for the prevention of ethanol formation in blood and urine specimens; however, our laboratory receives blood or urine in approximately 70% of cases. Thus, we frequently rely on tissue specimens for ethanol analysis. The postmortem tissue specimens received by our laboratory have generally been subjected to severe trauma and may have been exposed to numerous microbial species capable of ethanol production. With this in mind, we designed an experiment utilizing unadulterated tissue specimens obtained from aviation accident victims to determine the effectiveness of sodium fluoride at various storage temperatures for the prevention of microbial ethanol formation. We found that without preservative, specimens stored at 4 degrees C for 96 h showed an increase in ethanol concentration ranging from 22 to 75 mg/hg (average 42 +/- 15 mg/hg). At 25 degrees C, these same specimens showed an increase ranging from 19 to 84 mg/hg (average 45 +/- 22 mg/hg). With the addition of 1.00% sodium fluoride, there was no significant increase in ethanol concentration at either temperature.

The effects of temperature, pH, inoculum level, and NaCl on the growth and metabolism of Lactobacillus sanfranciscensis and Candida humilis in rye sourdough were determined. The temperature optima for growth of C. humilis and L. sanfranciscensis were 28 and 32 °C, respectively. Yeast growth was inhibited at 35 °C. The pH did not affect yeast growth in the range 3.5–5.5, whereas growth of L. sanfranciscensis was inhibited at pH 4.0. A NaCl concentration of 4% (flour base) inhibited growth of L. sanfranciscensis but not C. humilis. The effects of the process parameters on the formation of lactate, acetate, ethanol, and CO2 by the organisms were generally in agreement with their effects on growth. However, decreased formation of acetate by L. sanfranciscensis was observed at 35 °C although lactate and ethanol formation were not affected. In conclusion, the study provides a rationale for the stable persistence of L. sanfranciscensis and C. humilis in traditional sourdoughs and will facilitate the optimisation of sourdough fermentations in traditional and new applications.

The effects of different culture conditions on the expression level of human interferon-alpha2a (IFN-alpha2a) by using recombinant yeast were investigated in a 2.6-L jar fermentor. Appropriate supplement of glucose and the maintenance of residual glucose at a low level resulted in the reduction of ethanol formation and enhancement of the bioactivity of IFN-alpha2a to 4.9 x 106 from 3.1 x 10(6) IU/mL. When adenine was added evenly for 10-20 h of fermentation into the basal culture medium at a speed of 2 microg/mL of medium/h, OD600 was greatly increased to 24, and the protein increased to 276 mg/L. The content of ethanol generated was also reduced tremendously during the process, and as a result, 1.3 x 10(7) IU/mL of biologic activity was achieved. In the expression phase, pH had an important impact on expression level, which should be controlled at 5.5.

CO2 hydrogenation was carried out over alkali metals such as Li, Na and K promoted silica-supported Rh–Co catalysts (Rh–Co–M/SiO2). Na additive was most effective of the three alkali metals for ethanol formation over 5 wt% Rh–Co(1 : 1)/SiO2. The added amount of Na influenced product selectivity as well as CO2 conversion. The highest ethanol selectivity was obtained over 5 wt% Rh–Co–Na (1 : 1 : 0.5)/SiO2 catalyst. The mechanism of promotion effect of Na added amount was investigated by means of in situ FT-IR observation during reaction. The variation of Na added amount changed the ratio of Rh2–(CO)3 and bridged type adsorbed CO species to linear type one. This finding suggested that the amount of Na affected on the hydrogenation ability of Rh–Co/SiO2 catalysts, leading to the difference in CO2 hydrogenation activity.

Postmortem ethanol formation is a well-known problem in forensic toxicology. The aim of this study was to interpret findings of ethanol in blood, in a large collection of forensic autopsy cases, by use of the nonoxidative ethanol metabolites, ethyl glucuronide (EtG), and ethyl sulfate (EtS). In this study, according to previously published literature, antemortem ethanol ingestion was excluded in EtS-negative cases. Among 493 ethanol-positive forensic autopsy cases, collected during the study period, EtS was not detected in 60 (12 %) of the cases. Among cases with a blood alcohol concentration (BAC) of ≤ 0.54 g/kg, antemortem ethanol ingestion was excluded in 38 % of the cases, while among cases with a BAC of ≥ 0.55 g/kg, antemortem ethanol ingestion was excluded in 2.2 % of the cases. For all cases where ethanol was measured at a concentration >1.0 g/kg, EtS was detected. The highest blood ethanol concentration in which EtS was not detected was 1.0 g/kg. The median concentrations of EtG and EtS in blood were 9.5 μmol/L (range: not detected (n.d.) 618.1) and 9.2 μmol/L (range: n.d. 182.5), respectively. There was a statistically significant positive correlation between concentration levels of ethanol and of EtG (Spearman's rho=0.671, p

The hydration of ethene was carried out over H3PO4/SiO2 having various amounts of H3PO4. The rate of the ethanol formation increased markedly with the increasing H3PO4 loadings, in particular above 60–70 wt%. By X-ray diffraction (XRD), and 31 P and 29 Si MAS NMR methods, it was revealed that various silicon phosphates were produced in the preparation of the catalysts. The structures of the phosphates depended on the H3PO4 loadings. It was suggested that Si(HPO4)2·H2O species which formed at higher H3PO4 loadings were hydrolyzed to H3PO4 and SiO2 during the course of the reaction, yielding the catalysts with high performance. The bulk phase of the H3PO4 was involved in the reaction.