7 research outputs found

    PREVENTION MEASURES OF ENVIRONMENTAL RISKS GENERATED BY UNCONTROLLED STORAGE OF WASTES – A REVIEW

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    The issue regarding the negative impact on the human health and environment, as a result of waste storage by using improper methods remains of great actuality, especially with the increasing trend of the generated wastes quantity. The present paper aims to present the most efficient methods that can be used to reduce and prevent environmental risks caused by uncontrolled storage of agricultural waste. Will be treated theoretical aspects related to the actual state of waste management in the E.U. but also in Romania, methods of treating organic waste, as well as prevention measures of environmental risks

    PREVENTION MEASURES OF ENVIRONMENTAL RISKS GENERATED BY UNCONTROLLED STORAGE OF WASTES – A REVIEW

    Get PDF
    The issue regarding the negative impact on the human health and environment, as a result of waste storage by using improper methods remains of great actuality, especially with the increasing trend of the generated wastes quantity. The present paper aims to present the most efficient methods that can be used to reduce and prevent environmental risks caused by uncontrolled storage of agricultural waste. Will be treated theoretical aspects related to the actual state of waste management in the E.U. but also in Romania, methods of treating organic waste, as well as prevention measures of environmental risks

    Aspects regarding FEM simulation of stress in hammer mill working tool

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    Considering the need for development and improvement of biomass processing equipment, researchers bring contribution by making suggestions to design also through simulation and modelling of different stresses that occur on equipment’s working tools. In this paper the stress in hammer mill working tools was analysed using FEM simulation with the help of SolidWorks 2016 Premium, projecting the geometric model and FEM simulation for a MC 22 hammer mill. The hammer mill has a four bolts rotor on which are the hammer disposed. The hammer mills rotor frequency is about 2940 rot/min. An important result in FEM simulation was the fact that the maximum reaction in the hammer joint was 11635 N. After FEM simulation experimental research were done using shredded miscanthus and energetic willow, the mill being equipped alternately with 4 types of hammers, with corners processed differently

    Food Waste Management for Biogas Production in the Context of Sustainable Development

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    In the context of increasing pressure regarding the sustainable utilization of food waste in a circular economy, one of the trends is their biological transformation, through anaerobic digestion, into biogas as a renewable source of energy. We presented the physical-chemical properties of the main categories of food waste from different sources: dairy, meat, and poultry, fish, fruit and vegetable, cereal and bakery, brewing and winery industries, and others. Due to the high organic load, the presence of a multitude of nutrients, and an insignificant amount of inhibitors, food waste can be successfully used in the biogas production process in co-digestion with other materials. Physical (mechanical and thermal), chemical (alkali, acid, and oxidative), and biological (enzymatic, bacterial, and fungal) techniques have been widely used for pretreatment of different substrate types, including food waste. These pretreatments facilitate the degradation of pretreated food waste during anaerobic digestion and thus lead to an enhancement in biogas production. The purpose of this study is to review the situation of food waste generated in the food industry and to formulate the main trends of progress in the use of this waste in the anaerobic digestion process

    Influence of the process parameters on mechanical properties of the final parts obtained by selective laser sintering from PA2200 powder

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    The paper describes how the process parameters affects the mechanical characteristics of laser selective sintered (SLS) parts used in applications of medical, automotive and aerospace fields. The greatest advantage of the additive manufacturing (AM) technology in the medical field is that it allows the use of the patient's medical CT images to obtain specific implants, providing high benefits for both patients and physicians. Despite its increasing use and advantages, the AM process has a series of problemssuch as: the difficulty in obtaining quality part, process interruption or manufacturing part failure. As such, there have been developed experimental researches in order to establish a correlation between the process parameters and the finished part properties. For this analysis, PA 2200 polyamide specimenswere obtained by SLS and subjected to tensile tests. The results correlate the process parameters, providing proof that the tensile properties of SLS specimen are dependent of orientation, position and preheating temperature. Based on the correlation between the process parameters and properties of the PA2200 polyamide, this paper provides a better understanding of the AM process and allows an anticipation onthe best parameters to be used on different parts, leading the optimizing of component properties for medical applications

    Inflammatory-Driven Angiogenesis in Bone Augmentation with Bovine Hydroxyapatite, B-Tricalcium Phosphate, and Bioglasses: A Comparative Study

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    Introduction. The clinical use of bioactive materials for bone augmentation has remained a challenge because of predictability and effectiveness concerns, as well as increased costs. The purpose of this study was to analyse the ability to integrate bone substitutes by evaluating the immunohistochemical expression of the platelet endothelial cell adhesion molecules, vascular endothelial growth factor, collagen IV, laminin, and osteonectin, in the vicinity of bone grafts, enabling tissue revascularization and appearance of bone lamellae. There is a lack of in vivo studies of inflammatory-driven angiogenesis in bone engineering using various grafts. Methods. The study was performed in animal experimental model on the standardized monocortical defects in the tibia of 20 New Zealand rabbits. The defects were augmented with three types of bone substituents. The used bone substituents were beta-tricalcium phosphate, bovine hydroxyapatite, and bioactive glasses. After a period of 6 months, bone fragments were harvested for histopathologic examination. Endothelial cell analysis was done by analysing vascularization with PECAM/CD31 and VEGF and fibrosis with collagen IV, laminin, and osteonectin stains. Statistical analysis was realized by descriptive analysis which was completed with the kurtosis and skewness as well as the Kruskal-Wallis and Mann-Whitney statistical tests. Results. The discoveries show that the amount of bone that is formed around beta-tricalcium phosphate and bovine hydroxyapatite is clearly superior to the bioactive glasses. Both the lumen diameter and the number of vessels were slightly increased in favor of beta-tricalcium phosphate. Conclusion. We can conclude that bone substitutes as bovine bone and beta-tricalcium phosphate have significant increased angiogenesis (and subsequent improved osteogenesis) compared to the bioactive glass. In our study, significant angiogenesis is linked with a greater tissue formation, indicating that in bone engineering with the allografts we used, inflammation has more benefic effects, the catabolic action being exceeded by the tissue formation

    La phrase : carrefour linguistique et didactique

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    Les contributions rassemblĂ©es dans ce volume interrogent la notion de phrase, d’un double point de vue linguistique et didactique. Par leur diversitĂ© et leur complĂ©mentaritĂ©, elles apportent un Ă©clairage particulier sur cette notion plurielle, analysĂ©e pour le français et pour d’autres langues, dans une perspective contrastive. Un premier volet linguistique propose une rĂ©flexion sur la nature mĂȘme de la phrase et son identification, par le biais d’analyses portant sur certains constituants ciblĂ©s, ou de rĂ©flexions sur la dimension Ă©nonciative, discursive et interprĂ©tative de cette unitĂ©. Cette partie fait clairement apparaĂźtre la nĂ©cessitĂ© d’une rĂ©flexion sur les critĂšres dĂ©finitoires pertinents, susceptibles de rendre compte au mieux du fonctionnement de la langue. Le second volet offre une perspective didactique : Ă  partir d’analyses de supports d’enseignement, de dispositifs d’apprentissage ou encore de productions d’élĂšves, les contributions interrogent l’enseignement-apprentissage de la notion en Français Langue Maternelle comme en Français Langue ÉtrangĂšre. Ces analyses mettent notamment en Ă©vidence la nĂ©cessitĂ© d’établir des passerelles entre linguistique et didactique et interrogent de fait la formation des enseignants sur ces questions centrales.Actes du 10ecolloque international franco-roumain organisĂ© par les laboratoires Grammatica (EA 4521) et Circeft-Escol (EA 4384), UniversitĂ© d’Artois, 3-5 juin 2015. Ouvrage publiĂ© avec le concours du laboratoire Grammatica (EA 4521), de l’universitĂ© d’Artois et d’Arras UniversitĂ©
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