47 research outputs found

    Számítástechnikai és kibernetikai módszerek alkalmazása az orvostudományban és a biológiában

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    A Neumann János Számítógép-tudományi Társaság Szegeden, 1971 december 6-8-án tartott 2. Neumann Kollokviumának anyaga,  mely a Kollokviumon elhangzott 30 belföldi és 3 külföldi előadást, a kisszámitógépek orvosi alkalmazásairól tartott kerekasztal konferencia anyagát, valamint a résztvevők névsorát tartalmazza

    Hydroconversion of acetic acid over carbon aerogel supported molybdenum catalyst

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    High surface area carbon aerogels with increasing molybdenum content were obtained by carbonization of resorcinol-formaldehyde polymer aerogels after incipient wetness impregnation (IWI). The Mo(VI) form of the impregnant was converted into different molybdenum species during the heat treatment, resulting in samples with substantially different surface and bulk compositions. The samples were tested in the hydroconversion reaction of acetic acid, a model biomass. The reaction pathways and the product distribution were governed by the accessibility of the carbon surface as well as by the amount and form of Mo. The highest selectivity for ethanol was 16 %, when 85 % of the acetic acid was converted. Post-catalyst analysis of the aerogels revealed that their morphology and chemistry changed substantially during the redox processes. The products of each of the three potential pathways (hydrogenolysis, ketonization and consecutive reduction) oxidized the surface even in the reductive hydrogen flow

    Environmental and Toxicological Impacts of Glyphosate with Its Formulating Adjuvant

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    Environmental and toxicological characteristics of formulated pesticides may substantially differ from those of their active ingredients or other components alone. This phenomenon is demonstrated in the case of the herbicide active ingredient glyphosate. Due to its extensive application, this active ingredient was found in surface and ground water samples collected in Békés Country, Hungary, in the concentration range of 0.54–0.98 ng/ml. The occurrence of glyphosate appeared to be somewhat higher at areas under intensive agriculture, industrial activities and public road services, but the compound was detected at areas under organic (ecological) farming or natural grasslands, indicating environmental mobility. Increased toxicity of the formulated herbicide product Roundup compared to that of glyphosate was observed on the indicator aquatic organism Daphnia magna Straus. Acute LC50 values of Roundup and its formulating adjuvant polyethoxylated tallowamine (POEA) exceeded 20 and 3.1 mg/ml, respectively, while that of glyphosate (as isopropyl salt) was found to be substantially lower (690-900 mg/ml) showing good agreement with literature data. Cytotoxicity of Roundup, POEA and glyphosate has been determined on the neuroectodermal cell line, NE-4C measured both by cell viability test and holographic microscopy. Acute toxicity (LC50) of Roundup, POEA and glyphosate on NE-4C cells was found to be 0.013±0.002%, 0.017±0.009% and 6.46±2.25%, respectively (in equivalents of diluted Roundup solution), corresponding to 0.022±0.003 and 53.1±18.5 mg/ml for POEA and glyphosate, respectively, indicating no statistical difference between Roundup and POEA and 2.5 orders of magnitude difference between these and glyphosate. The same order of cellular toxicity seen in average cell area has been indicated under quantitative cell visualization. The results indicate that toxicity of the formulated herbicide is caused by the formulating agent, but in some parameters toxicological synergy occurs between POEA and glyphosate

    Process Design of Continuous Powder Blending Using Residence Time Distribution and Feeding Models

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    The present paper reports a thorough continuous powder blending process design of acetylsalicylic acid (ASA) and microcrystalline cellulose (MCC) based on the Process Analytical Technology (PAT) guideline. A NIR-based method was applied using multivariate data analysis to achieve in-line process monitoring. The process dynamics were described with residence time distribution (RTD) models to achieve deep process understanding. The RTD was determined using the active pharmaceutical ingredient (API) as a tracer with multiple designs of experiment (DoE) studies to determine the effect of critical process parameters (CPPs) on the process dynamics. To achieve quality control through material diversion from feeding data, soft sensor-based process control tools were designed using the RTD model. The operation block model of the system was designed to select feasible experimental setups using the RTD model, and feeder characterizations as digital twins, therefore visualizing the output of theoretical setups. The concept significantly reduces the material and instrumental costs of process design and implementation
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