537 research outputs found

    Kinetic Analysis of the Hydrogenolysis of Lower Polyhydric Alcohols: Glycerol to Glycols

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    The production of ethylene glycol and propylene glycol from higher polyhydric alcohols has been parametrically examined numerous times. However, efforts to develop improved catalyst systems require a better understanding of the reaction mechanism. Glycerol conversion to the glycols represents an initial system for developing an improved mechanistic understanding of the conversion of the more complex higher polyhydric alcohols. Batch reactor studies with ruthenium on carbon catalysts were performed at two pH levels to obtain kinetic data. Langmuir-Hinshelwood-type models were developed from the experimental data to describe the hydrogenolysis of glycerol into ethylene glycol and propylene glycol as well as further degradation of the glycols. Detailed information on the competitive adsorption coefficients for the reaction species was determined, which led to conclusions about the limitations of previous parametric analysis

    Quantifying the sustainability of agriculture

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    The rural sustainability index is a scientifically based tool to quantify the performance of agriculture. The sustainability of crop production is quantified from three perspectives; people, planet and profit. Within each perspective, one condition was selected that must be met to warrant agriculture. These are: No hazardous work should be used within the crop production chain; agricultural crops should not be grown on land allocated to nature by national law or regulations and, when a GM-crop is present or is introduced in a region, it should not harm development opportunities of other farmers. If these excluding conditions are met, the sustainability of agriculture is assessed through five performance indicators on school attendance, water use and consumption, fertilizer use, pesticide use, and farm income. For each of the five indicators, critical values and target values have been given that limit the transition range between non-sustainable and sustainable production. The five indicators are combined into a sustainability index. The index aims at improving the socio-economic position of farmers while protecting the environment

    Caracterização física das chapas de partículas com os rejeitos oriundos da cana-de-açúcar e das folhas de bambu

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    A problemática do descarte correto dos resíduos sólidos gerados nos diferentes processos industriais faz parte das questões ambientais discutidas na atualidade. Nesse sentido, este trabalho visa estabelecer uma nova alternativa na disposição final de dois rejeitos por meio da produção compósitos para chapas de partículas e, a avaliação das propriedades físicas. O enfoque foi dado à reutilização do bagaço da cana-de-açúcar, originário do processamento da Saccharum officinarum, resíduo oriundo da usina Paraíso Bioenergia, produtora de açúcar e álcool, localizada no município de Torrinha-SP; além das folhas caulinares do bambu da espécie Dendrocalamus giganteus. Para tanto, foram produzidas chapas em seis diferentes tratamentos – 100%, 75%, 50%, 40%, 25% e 0% de bagaço de cana, em relação à massa total dos compósitos, sendo completadas com as folhas de bambu trituradas. Tais chapas foram produzidas e distinguidas por meio de ensaios normalizados da norma NBR 14.810-3 (2002), nas quais foram determinados os coeficientes de teor de umidade (variação de 8,8% a 11,94%) e, absorção (56,3% a 71,3%) e massa específica (0,69 g/cm3 a 0,74 g/cm3).In present days, the disposition of solid residues generated in industrial processes is one of the most important environment questions. In this context, the aim of this work is to establish an alternative to employ these residues, producing particleboards, and evaluation of physical property. The mean focus of the word is reusing: sugar cane bagasse, from processing Saccharum officinarum in Paraíso Bioenergia plant (Torrinha, SP), that produces sugar and ethanol; and caulinar leaves of bamboo Dendrocalamus giganteus. Particleboards were produced in six different insume fractions: 100%, 75%, 50%, 40%, 25% e 0% (sugar cane bagasse) related to total composite mass, completed with bamboo caulinar leaves. The panels were evaluated using normative recommendations from NBR14810-3 (2002) to determine moisture content (ranging from 8.8 % to 11.9%), water absorption (56,3 % to 71,3 %), and density (0,69 g/cm3 to 0,74g/cm3

    Developing an ML pipeline for asthma and COPD: The case of a Dutch primary care service

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    A complex combination of clinical, demographic and lifestyle parameters determines the correct diagnosis and the most effective treatment for asthma and Chronic Obstructive Pulmonary Disease patients. Artificial Intelligence techniques help clinicians in devising the correct diagnosis and designing the most suitable clinical pathway accordingly, tailored to the specific patient conditions. In the case of machine learning (ML) approaches, availability of real-world patient clinical data to train and evaluate the ML pipeline deputed to assist clinicians in their daily practice is crucial. However, it is common practice to exploit either synthetic data sets or heavily preprocessed collections cleaning and merging different data sources. In this paper, we describe an automated ML pipeline designed for a real-world data set including patients from a Dutch primary care service, and provide a performance comparison of different prediction models for (i) assessing various clinical parameters, (ii) designing interventions, and (iii) defining the diagnosis

    The Thickness of a Rigid Water Layer on Quartz From Measurements of Newton\u27s Rings (Abstracts)

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    Newton\u27s rings produced by a quartz plate and lens in a slit source of light were observed in a low power traveling microscope. The square of the radius of the rings ( r) plotted against the order of the ring ( n) from the center yields a straight line whose intercept on the axis where n = 0 is shown to be a function of the vertical separation of the lens and plate but not a function of the index of refraction of the medium between them nor the angle of incidence of the light. The ring radii were measured with air and with water between the lens and plate. The graphs for the two cases have different intercepts which is interpreted as indicating a rigid water multilayer between the quartz surfaces of the order of 200 AO in thickness

    Antibiotica in de bodem. Een pilotstudie.

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    In het kader van een overeenkomst tussen Stichting Kennisontwikkeling Kennisoverdracht Bodem (SKB) en een breed consortium en klankbordgroep is een pilotstudie uitgevoerd naar veterinaire antibiotica in de bodem en het grondwater

    Post-discharge Telemonitoring of Physical Activity, Vital Signs, and Patient-Reported Symptoms in Older Patients Undergoing Cancer Surgery

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    BACKGROUND: Postoperative home monitoring could potentially detect complications early, but evidence in oncogeriatric surgery is scarce. Therefore, we evaluated whether post-discharge physical activity, vital signs, and patient-reported symptoms are related to post-discharge complications and hospital readmissions in older patients undergoing cancer surgery. METHODS: In this observational cohort study, we monitored older patients (≥65 years of age) undergoing cancer surgery, for 2 weeks post-discharge using tablet-based applications and connected devices. Outcome measures were post-discharge complications and readmissions; physical activity and patient-reported symptoms over time; and threshold violations for physical activity (step count 38°C; blood pressure 150/100 mmHg; heart rate 100 bpm; weight -5% or +5% of weight at discharge); and patient-reported symptoms (pain score greater than the previous day; presence of dyspnea, vomiting, dizziness, fever). RESULTS: Of 58 patients (mean age 72 years), 24 developed a post-discharge complication and 13 were readmitted. Measured parameters indicated 392 threshold violations out of 5379 measurements (7.3%) in 40 patients, mostly because of physical inactivity. Patients with readmissions had lower physical activity at discharge and at day 9 after discharge and violated a physical activity threshold more often. Patients with post-discharge complications had a higher median pain score compared with patients without these adverse events. No differences in threshold violations of other parameters were observed between patients with and without post-discharge complications and readmissions. CONCLUSION: Our results show the potential of telemonitoring older patients after cancer surgery but confirm that detecting post-discharge complications is complex and multifactorial
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