Volatile Fatty Acids in Some Brands of Whisky, Cognac and Rum

SUMMARY— Gas chromatography was applied to eight different types of whisky, two of cognac, one of brandy, and four of rum to determine the relative proportions of volatile fatty acids; with the lower molecular acids as free acids, but upwards from caprylic acid as methyl esters. Acetic acid and the total amount of volatile acids were measured quantitatively. Rum contained the largest amount of volatile acids, 600 mg/L, while one of the brands of Scotch whisky contained the least, 90 mg/L. Acetic acid represented 40–95% of the total amount of volatile acids in the whisky; for cognac and brandy, the value was .50–75%, and for rum 75–90%. The relative amounts have been reported for 21 acids, with acetic acid excluded. Capric, caprylic and lauric acid were the main components in whisky, cognac and brandy. Of the beverages analyzed, rum contained the largest quantity of lower fatty acids, particularly propionic and butyric acid; the main component of Jamaican rum was propionic acid. The main components of the group of long-chain fatty acids were myristic, palmitic and palmitoleic acids. Scotch whisky contained equal amounts of palmitic and palmitoleic acid; palmitoleic acid regularly appeared in smaller amounts in the other beverages     

CO2 methanation on hard-templated NiOCeO2 mixed oxides

Mesostructured NiOCeO₂ mixed oxides, with Ni loadings in the range 5–35 wt% (g_Ni/g_CeO2), were synthesized by the hard template procedure using SBA-15 as the template. A hard-templated CeO₂ was also prepared and used as the support for depositing Ni (5–35 wt%) by impregnation. Two NiOAl₂O₃ catalysts were synthesized for comparison, by impregnating nickel on a commercial γ-alumina. All the samples were characterized by different techniques as to their chemical composition, structure, morphology, texture, and redox features. The catalytic performance was investigated in the CO₂ methanation reaction after mild reduction pretreatment (H₂ at 400 °C for 1 h). Catalytic testing was performed under atmospheric pressure, 300 °C, 72,000 cm³ h^?1 g_cat^?1, and stoichiometric H₂/CO₂ molar ratio. High catalytic activity, with CH₄ selectivity values ≥ 93 mol%, was obtained with the NiOCeO₂ mixed oxides (CO₂ conversions up to 76 mol%). When γ-Al₂O₃ was used as the support, catalysts with low activity (CO₂ conversion ≤ 20 mol%) were obtained. On selected samples, additional catalytic runs were also performed for reaction times up to 30 h or with a higher space velocity value. The catalytic results were explained by taking into account the role of the nickel-ceria interactions both during the reduction of NiO and in the reactants activation.     

钇-90微球治疗肝脏恶性肿瘤的术前肝血管评估 ——钇-90微球放射栓塞系列回顾（三）

【摘要】 钇-90（90Y）放射栓塞的潜在风险是在灌注微球过程中意外发生非靶血管栓塞。因此,术前采用肝动脉造影的方法来仔细确认有无潜在风险的动脉和血管交通尤其重要。完整的术前肝血管评估包括选择性肝动脉造影、预防性栓塞有导致90Y微球异位栓塞风险的动脉和确定继发于肿瘤病理性动静脉瘘产生的肝肺分流。本文将讨论90Y栓塞治疗过程中有可能引起非靶血管栓塞的相关动脉解剖以及如何评估这些血管的风险,预防非靶血管栓塞发生的方法。
     

Monitoring of Anionic Surfactants in a Wastewater Treatment Plant of Algiers Western Region by a Simplified Spectrophotometric Method

Evaluation of anionic surfactant (AS) quantities in the environment has been the subject of intensive worldwide investigation. Even so, significant questions related to their presence in Algerian wastewaters discharged into the Mediterranean Sea remain. For the first time, monitoring of AS in a wastewater treatment plant (WWTP) located about 30 km west of Algiers was carried out. Four sampling points were selected to inspect the behavior of AS and investigate surfactant removal efficiencies of the WWTP: untreated wastewaters (UW), samples clarified via primary treatment, samples biologically treated and treated waters. To achieve this work, a spectrophotometric method of AS determination has been developed. Dioctyl sulfosuccinate sodium was chosen as a reference because of its low costs and its high response, compared to other AS commonly used by this method. The effects of pH, time of extraction, and washing step were studied. The volume of solvent was optimized. The calibration curve was linear and exhibited a significant coefficient of correlation. The lower limit of detection was found to be around 10^?6 M. Mechanical and biological treatments remove 53 % of AS from wastewaters before being discharged into the aquatic environment. It was found that the concentration of AS discharged into the Mediterranean Sea in the studied region reaches 10^?4 M.     

Bringing maker practices to school: tracing discursive and materially mediated aspects of student teams’ collaborative making processes

The present investigation aimed to analyze the collaborative making processes and ways of organizing collaboration processes of five student teams. As a part of regular school work, the seventh-grade students were engaged in the use of traditional and digital fabrication technologies for inventing, designing, and making artifacts. To analyze complex, longitudinal collaborative making processes, we developed the visual Making-Process-Rug video analysis method, which enabled tracing intertwined with social-discursive and materially mediated making processes and zoomed in on the teams’ efforts to organize their collaborative processes. The results indicated that four of the five teams were able to take on multifaceted epistemic and fabrication-related challenges and come up with novel co-inventions. The successful teams’ social-discursive and embodied making actions supported each another. These teams dealt with the complexity of invention challenges by spending a great deal of their time in model making and digital experimentation, and their making process progressed iteratively. The development of adequate co-invention and well-organized collaboration processes appeared to be anchored in the team’s shared epistemic object.

     

Investigation of the Importance of Spatial Resolution for Two-Dimensional Shallow-Water Model Accuracy

The importance of spatial resolution for two-dimensional shallow-water model accuracy has been investigated by testing the effect of mesh refinement on two test cases based on laboratory dam-break experiments. A balanced first-order accurate upwind Q-Scheme and a second-order accurate upwind Hancock Monotone Upstream-centered Scheme for Conservation Laws scheme were both first validated on an analytical test, and then applied to the experimental dam-break test cases on four meshes of different density. Simulation results were evaluated through comparison of experimental and computed water level values at several available gauge points. Model sensitivity analysis showed that (1) mesh density was not critical for results accuracy; (2) excessive mesh refinement somewhat deteriorated the results; and (3) optimal spatial resolution was relatively low. Response is shown to be highly complex and no simple relation between spatial resolution and model accuracy has been found.