8 research outputs found
Cercetări privind influenţa metodei de fertilizare şi irigare a culturii de tomate asupra producţiei
The research of this study was carried out at the University of Agricultural Sciences and Veterinary Medicine "Ion Ionescu de la Brad" in Iasi. The experience was set up in a semicircular solar cell where the fertilization regime was pursued: fertilization by irrigation water, fertilization with classical fertilizers, fertilization with microorganisms and non-fertilized. The irrigation was dripped. The tomato production showed a difference from the control of 52.43 t/ha, in the fertilized variant, being considered positively very significant. In the case of tomatoes it was found that the fertilization is clearly superior to the other methods used
Simularea CFD a curgerii mustului într-un hidrociclon
The hydrocyclone is an equipment for clarification and separation of the solid particles, in suspension in a liquid, based on the density difference. The flow description in a hydrocyclone is much more complex compared to a cyclone for gaseous dispersions, as it appears three liquid-gas-solid components (the appearance of the air core), although the overall separation mechanisms are similar. Over time, many experiments have been carried out to determine the flow in a hydrocyclone.The proposed experimental methods are expensive and difficult to implement in technical terms, being limited to a dispersed liquid phase.Given these deficiencies, in the last two decades, have been developed models of fluid flow dynamics (CFD) based on flow fundamentals.The paper aims is to CFD simulate the flow of must during the working process of a hydrocyclone
Separarea şi caracterizarea principalelor fracţiuni de proantocianidine din seminţele de struguri
Grape seeds, as waste products of the winemaking industry, contain large amounts of monomers, oligomers and more highly polymerised proanthocyanidins (PA), being a good source of phytochemicals for the production of antioxidative dietary supplements. PA from defatted grape seeds were extracted by precipitation with diethyl ether from the crude alcoholic extract and fractionated into monomers (FI), oligomers (FII) and polymers (FIII) of flavan-3-ols by their separation on C18 Sep-Pak cartridges. FIII was the predominant class of proanthocyanidins (82.22%), while monomeric PA has only 5.71% of total. The ratio PA (by vanillin assay) / tannins (Bate-Smith assay) indicates the highest degree of polymerisation (DP) in FIII fraction (1.28). Thin layer chromatography (TLC) confirmed the presence of monomers in FI, the DP increasing significantly for the next two fractions. Oligomeric and polymeric PA showed the highest antioxidant activity (% scavenged DPPH), but the synergic antioxidant effect of PA classes was also observed
Cercetări privind utilizarea ca biomasa a coardelor de viţă de vie rezultate de la tăierea în uscat a plantaţiilor viticole
At the global level, biomass is considered one of the main forms of renewable energy, as it ensures the conservation of the sun's energy in chemical form, being one of the most popular and universal resources on Earth, used for energy purposes since the discovery of fire by man. Today, biomass can be used for different purposes from room heating to the production of electricity and fuel for cars. Biomass is the biodegradable part of agricultural products, waste and residues, including plant and animal substances, forestry and related industries, as well as the biodegradable part of industrial and urban waste. Considering these elements, we can consider that vine plantations can make a significant contribution to the development of the biomass source, by using the vine ropes resulted from the cuts in the land.The research aimed the determination of the biomass potential of vine plantations, were harvested ropes from wine varieties and at different dates during plant rest to determine the evolution of their humidity. The samples were taken from the didactic resort farm "Vasile Adamachi" plantation of the University of Agricultural Sciences and Veterinary Medicine "Ion Ionescu de la Brad" of Iasi. The varieties studied were: Busuioaca de Bohotin, Cabernet Sauvignon, Feteasca Alba, Feteasca Neagra, Feteasca Regala, Muscat Ottonel, Pinot Noir and Sauvignon Petit.After the research carried out, it was found that the humidity of the strings is different, depending on the variety and the date of harvest
Cercetari privind utilizarea ca biomasa a ramurilor rezultate de la tăierile de fructificare de la diferite specii de pomi fructiferi
Biomass is the most abundant renewable resource on the planet. This includes absolutely all the organic material produced by the metabolic processes of living organisms. Biomass can be used in the form of solid or liquid fuels, being used both for direct combustion, for space heating, and for liquid biofuel (bioethanol) for supply the thermal engines. The research carried out had as an objective the collection of the branches resulting from the fruiting cuts from the varieties of apple, hair, cherry and plum, located in the plantations of the Experimental resortfrom the USAMV Iași, Farm “V. Adamachi”, and the determination of the calorific power for each category of fruit trees. From the analysis of the results it appears that the calorific power is different from one species to another, as well as depending on the variety of the respective species. Also, the energy value of the harvested branches is high, being close to that of firewood, which allows us to specify that they can be valued as biomass, constituting an important renewable source of solid biofuel, which can be used in the form of pellets and lighter
Assessment of quality characteristics of new Vitis vinifera L. cultivars for temperate climate vineyards
Since quality requirements for table grapes are mainly related to their physico-chemical and mechanical features, the aim of this work was to provide useful data for grape producers and consumers concerning the quality characteristics of table grapes of five new Vitis vinifera L. cultivars created in Romania and tending to spread within the temperate climate vineyards. During grape maturation, sugar content increased in a lesser extent than the reducing of total acidity, a balanced taste of grapes was given by the decrease in total acidity rather than sugar accumulation. Grapes of analysed cultivars showed lower concentrations of ascorbic acid and a higher content of organic nitrogenous compound. Berries with higher weight and volume (Transilvania cv.) incurred a higher mechanical deformation, while long berries (Gelu cv.) showed higher resistance to detachment from the pedicel, indicating higher resistance of grapes to packing, transport and storage. Antioxidant activity of mature grapes was high, but involvement of nonflavonoids in increasing the antioxidant capacity was statistically non-significant. Seeded table grapes of new Vitis vinifera L. cultivars showed superior physico-chemical and mechanical characteristics, indicating their high quality in the conditions of temperate continental climate, and promoting the studied cultivars as important grapevine germplasm resources
Evaluarea rezistenţei la desprindere şi compresiune a bacelor unor soiuri noi Vitis vinifera L. pentru struguri de masă
Since quality requirements for table grapes are closely relatedto their mechanical characteristics, the aim ofthis work was the assessment of berry resistance to detachment from the pedicel and its resistance to compression at five new Vitis vinifera L. cultivars for table grapes: Gelu, Milcov, Napoca, Splendid and Transilvania. The determinations made on the mature berries consisted in the analysis of the normal pressing force and the deformation under its influence, as well as the force required for the detachment of berries from the pedicels, using a CETR UMT-2 tribometer. Grape berries with higher weight and volume and larger diameter (Transilvania cv.) incurred a higher mechanical deformation, while long berries (Gelu cv.) showed higher resistance to detachment from the pedicel probably due to a more pronounced development of vascular bundles, indicating a higher resistance of grapes to handling, packing, transport and storage