INCREASING THE BIOLOGICAL RESISTANCE OF GYPSUM BY MEANS OF SILVER, CALCIUM AND COPPER IONS

The article focuses on the effects of additives increasing biological resistance of gypsum against degradation of the material. In this study we use silver nitrate, calcium oxide and copper sulphate as an additive that improves biological resistance of gypsum composites. The amount of addition was calculated so that the amount of ions was 0.1, 0.3 and 0.5 wt. %. Microbial degradation was determined as the degree of resistance of materials to the occurrence of bacteria and molds by optical and electron microscope. The results obtained from these samples were compared with references materials created in the laboratory and available on today’s market. The results show a positive effect of silver and copper ions on the bioresistance of gypsum.

Species effect on decay resistance of wood exposed to exterior conditions above the ground in Spain

The objective of this study is to evaluate the effect of the species on the biological resistance of wood against decay and to propose corrective values of the critical dose. To evaluate the species effect, the evolution of the number of days per year with moisture content exceeding 18% was assessed in flat sawn 20x100x750 mm3 test samples of Laricio, Scots and Radiata pines and also of Norway spruce, Eucalypt (globulus) and sweet chestnut during the years 2016, 2017 and 2018, exposed at seven locations in Spain with the most representative Spanish climates. A value of 1.0 is proposed for the four conifers, 2.51 for the Eucalypt and 1.84 for the Sweet chestnut. As regards the species effect it was not possible to separate that corresponding to the different wetting/releasing ability of each species and that of their crack susceptibility, both aspects having to be evaluated together as “species factor”.

Propriedade da Fibra de Coco: Uma Revisão Sistemática

O coco é um fruto presente na agricultura de diversos países, estimando-se um consumo 61,3 milhões de toneladas colhidas por ano em cerca de 12 milhões de hectares. O principal consumo do fruto está relacionado com a indústria alimentícia, sendo consumida a sua água, a polpa que é a parte comestível do fruto e que gera demais derivados alimentícios. Entretanto, após a utilização das partes comestíveis do fruto, é possível utilizar o seu subproduto extraindo a fibra do mesocarpo do fruto, sendo este compósito conhecido como fibra de coco. A fibra vegetal proveniente do coco, fibra de coco, é amplamente utilizada em diversos setores econômicos em função de suas características de durabilidade, rigidez, impermeabilidade, resistência contra ataques biológicos, resistência à tração e termoacústica, se destacando das demais fibras vegetais. Estas características estão ligadas com a sua composição de lignocelulósicos desta fibra, sendo que esta apresenta maiores concentrações de lignina (45 – 46%) em comparação com outras fibras naturais. Esta revisão narrativa é baseada em livros, artigos, seminários e demais obras científicas que abordam o tema de fibras vegetais e fibra de coco, sendo que o principal objetivo é fazer um levantamento sobre este compósito abordando sua origem, comportamentos químicos, físicos, mecânicos e características gerais. Palavras-chave: Fibra de Coco. Coco. Fibra Vegetal. Abstract Coconut is a fruit present in agriculture in several countries, with an estimated consumption of 61.3 million tons of tons per year in about 12 million hectares. The main fruit consumption is related to the food industry, being consumed its water, the pulp that is the edible part of the fruit and that generates other food derivatives. However, after using the edible parts of the fruit, it is possible to use its by-product by extracting the fiber from the fruit's mesocarp, this composite being known as coconut fiber. Vegetable fiber from coconut, coconut fiber, is widely used in several different sectors due to its characteristics of durability, rigidity, impermeability, resistance against biological resistance, tensile and thermoacoustic resistance, standing out from other vegetable fibers. These characteristics are associated with its lignocellulosic composition of this fiber, being present higher lignin (45 - 46%) in comparison with other natural fibers. This narrative review is based on books, articles, seminars and other scientific works that address the topic of vegetable fibers and coconut fiber, and the main objective is to survey this composite addressing its origin, chemical, organic, mechanical and general features. Keywords: Coconut Fiber. Coconut. Vegetable Fiber.

EVALUATION OF THE AGROBIOLOGICAL AND TECHNOLOGICAL POTENTIAL OF SOME VALUABLE HYBRID ELITE OBTAINED AT R.D.S.V.O. ODOBEŞTI

Over time at Research and Development Stationfor Viticulture and Oenology Odobeşti, numerous intra- and interspecific sexual hybridizations have been carried out, in order to obtain new cultivars, with high productive and qualitative potential, with disease tolerances, resistant to stress factors, very well adapted to the climatic conditions specific to Vrancea vineyards.Thus, valuable hybrid elites were obtained, which represent a permanent source for the selection, approval and promotion of new grape cultivars. In order to evaluate the agrobiological and technological potential of some valuable hybrid elites, in the period 2016 - 2018, two elites were studied: ‘E.H. 10-1-6’ and ‘E.H. 6-1-1’. The results obtained from this study showed that these hybrid elites have a high productive and qualitative potential, show high biological resistance to the main diseases of the vine, and can be proposed for approval in order to improve the national assortment, in the context of sustainable viticulture.