OALib Journal期刊

ISSN: 2333-9721




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匹配条件: “Viorel F?tu” ,找到相关结果约147078条。
Data on the Hawthorn Psyllid Cacopsylla melanoneura (F rster) Populations in Southeast Romania
Constantina Chireceanu,Viorel Ftu
Ecologia Balkanica , 2012,
Abstract: In 2009, the hawthorn psyllid, Cacopsylla melanoneura (F rster) (Hemiptera: Psyllidae) was investigated in B neasa area within the framework of a pests monitoring program initiated at the Research Development Institute for Plant Protection Bucharest. This psyllid is an important pest for apple orchards in Europe, as it is a vector of the apple proliferation phytoplasma. The overwintered adults colonized the hawthorn and apple as well as the sweet cherry plants in the neighboring of the apple orchards starting with the beginning of March. Egg laying period began in late March (on hawthorn) and early April (on apple). The larvae completed their development on hawthorn and on apple between middle April and June. No eggs or larvae were found on sweet cherry. The adults of the new generation were observed since the beginning of May until June, after that they left the hawthorn and apple plants. Our data indicated that the hawthorn, compared with apple, is mostly preferred as host plant for C. melanoneura, thus the most abundant populations of this insect have been observed on this.
Every Tiling of the First Quadrant by Ribbon L n-Ominoes Follows the Rectangular Pattern  [PDF]
Viorel Nitica
Open Journal of Discrete Mathematics (OJDM) , 2015, DOI: 10.4236/ojdm.2015.52002
Abstract: Let \"\" and let \"\" be the set of four ribbon L-shaped n-ominoes. We study tiling problems for regions in a square lattice by \"\". Our main result shows a remarkable property of this set of tiles: any tiling of the first quadrant by \"\", n even, reduces to a tiling by \"\"and \"\" rectangles, each rectangle being covered by two ribbon L-shaped n-ominoes. An application of our result is the characterization of all rectangles that can be tiled by \"\", n even: a rectangle can be tiled by \"\", n even, if and only if both of its sides are even and at least one side is divisible by n. Another application is the existence of the local move property for an infinite family of sets of tiles: \"\", n even, has the local move property for the class of rectangular regions with respect to the local moves that interchange a tiling of an \"\" square by n/2 vertical rectangles, with a tiling by n/2 horizontal rectangles, each vertical/horizontal rectangle being covered by two ribbon L-shaped n-ominoes. We show that none of these results are valid for any odd n. The rectangular pattern of a tiling of the first quadrant persists if we add an extra \"\" tile to \"\", n even. A
Journal of Central European Agriculture , 2004,
Abstract: The researches took place in natural conditions of storage from October to March, and were aimed at two apple cultivars: Jonathan and Golden delicious. We had determinate the field and storage mycological flora which produces rotten stuff. The cultivar Golden delicious behaved as resistant in the storage period; the frequency (F%), the intensity (I%) and the degree of attack (D.A%) was low, for example the degree of attack in March touched 5,52%. The cultivar Jonathan breaked down after three month of storage, the frequency of attack being above 30%.
On the Large Synchronous Machine Parameters Calculatioin
Ioan Adrian Viorel,Jean Jacques Simond,Mai Tu Xuan,Liliana Vicol
Advances in Electrical and Electronic Engineering , 2004,
Abstract: The large synchronous generators were intensively studied, but not so many papers are entirely dedicated to the analythical calculation of the generator′s parameters. Therefore any contribution should be welcomed if it offers an improvement in the existing procedures or formulae. The paper is dealing with the large synchronous generator smagnetizing and leakage inductances calculation. A coherent algorithm is presented and the calculated parameters for a generator are given.
Nanocomposites Based on Conducting Polymers and Functionalized Carbon Nanotubes with Different Dopants Obtained by Electropolymerization  [PDF]
Florina Branzoi, Viorel Branzoi
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2014, DOI: 10.4236/jsemat.2014.43020

Nanocomposite films based on poly (3,4-ethylenedioxy thiophene) (PEDOT), functionalized single-walled carbon nanotubes and different dopants were studied. It was fabricated by a simple oxidative electropolymerization method. The dopant substances used were SDS (Sodium dodecyl sulfate) and tiron (1,2-Dihydroxybenzene-3,5-disulfonic acid disodium salt hydrate). These nano-composite films were grown electrochemically from aqueous solutions such that constituents were deposited simultaneously onto substrate electrode. The synthetic, morphological and electrical properties of the nanocomposite films obtained were compared. Scanning electron microscopy (SEM) revealed that the composite films consisted of nanoporous networks of SWCNTS (single-walled carbon nanotubes) coated with polymeric film. Cyclic voltammetry (CV), electro-chemical impedance spectroscopy (EIS) and FT-IR spectroscopy demonstrated that these composite films had similar electrochemical response rates to pure polymeric films but a lower resistance and much improved mechanical integrity. The negatively charged functionalized carbon nano-tubes (CNTSF) served as anionic dopant during the electropolymerization to synthesize polymer/CNTSF composite films. The specific electrochemical capacitance of the composite films is a significantly higher value than that for pure polymer films prepared similarly. Using these composite films, the modified electrodes with improved properties were obtained. (In this paper, for simplicity, the SWANTs-COOH group will be noted CNTsF which means functionalized carbon nanotubes.)

The Electrochemical Behaviour of PEDOT Film Electrosynthesized in Presence of Some Dopants  [PDF]
Florina Branzoi, Viorel Branzoi
Open Journal of Organic Polymer Materials (OJOPM) , 2015, DOI: 10.4236/ojopm.2015.54010
Abstract: Electropolymerization and characterization of poly(3,4-ethylene dioxythiophene) (PEDOT) doped with functionalized single-walled carbon nanotubes (SWANTs) polyaminobenzene sulfonic acid (PABS) and different dopants were studied. It was fabricated by a simple oxidative electropolymerization method. The nanocomposite coatings have been prepared by using electrochemical methods from aqueous solutions, such that the components were deposited onto platinum electrode substrate. The morphology of composite films was analyzed by scanning electron microscopy (SEM). The electrochemical and physical properties of the resulting composites were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR) techniques in 0.1 M LiClO4 aqueous solutions. The value of specific electrochemical capacitance of the composite films is considerably higher than that of the pure polymers films. The improved properties of the electrodes were obtained by using these composite films. The dopant substances used were sodium dodecyl sulfate (SDS) and 1,2-Dihydroxy- benzene-3,5-disulfonic acid disodium salt hydrate (tiron).
New Products against Apple Scab and Powdery Mildew Attack in Organic Apple Production
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2010,
Abstract: A study was undertaken on the effectiveness of some fungicides such as wettable sulphur, copper hydroxide, potassium bicarbonate and potassium bicarbonate mixed with potassium silicate against apple scab and apple powdery mildew attack, in the environmental conditions of Cluj-Napoca, Romania. The following cultivars were analyzed ‘Jonathan’, ‘Gala’, ‘Jonagold’, ‘Jonica’, ‘Golden Delicious’, ‘Idared’, ‘Granny Smith’ and ‘Starkrimson’, in an experiment conducted over two growing seasons (2009-2010), in five treatment variants. Potassium bicarbonate and a mixture between potassium bicarbonate and potassium silicate proved to be more effective in reducing the attack of apple scab and powdery mildew on leaves and fruit. Results were obtained for two years with favourable conditions of apple scab and powdery mildew development, when untreated variants exhibited an attack degree at a mean value of 49.77% for scab and 52.13% for powdery mildew. Potassium bicarbonate and potassium bicarbonate mixed with potassium silicate assured the best results in the case of the ‘Idared’, ‘Jonathan’, ‘Jonica’ cultivars regarding apple scab, and ‘Golden Delicious’, ‘Starkrimson’ and ‘Granny Smith’, regarding powdery mildew, where the mean value attack degree was reduced by about three times. The treatments with the products used in the experiments did not register symptoms of phytotoxicity on leaves or flowers. Given that this product is not toxic to human health, it becomes a perspective fungicide, especially for organic fruit tree growing in order to control apple scab and powdery mildew attack.
A Threefold Assessment of the Romanian Economy’s Eco-efficiency
Viorel Ni??
Romanian Journal of European Affairs (RJEA) , 2012,
Abstract: The present paper assesses the ecological sustainability of the Romanian economy from three different angles. The first two applications use the economy's energy and material consumption as proxy for its overall environmental impact. The third assessment approach is a qualitative and context-based one: the main obstacles to and opportunities for incorporating sustainability-competitiveness synergies into the Romanian industrial firms' management are identified. In the period 2000-2007, GDP growth was an important contributor to the Romanian economy's eco-efficiency levels, while the material and energy consumption remained constant or even increased. The predominance of competitive advantages based on low labour costs, high potential of increasing labour productivity, deficient environmental and industrial policies, and lack of awareness in both business and policy environment as to the beneficial role of resource productivity increase constitute significant obstacles to adopting competitive sustainability strategies. Fortunately, the relatively low levels of eco-efficiency and eco-innovation in industry offer in fact a wide scope of still unexploited win-win solutions. On the basis of the results, further research directions are sketched and several desirable public policy actions for enhancing the ecological sustainability of the Romanian economy are put forward.
Viorel Ro
Lex et Scientia , 2009,
Abstract: Tax avoidance, tax escaping represents tax evasion. Both in theory and in practice it is admitted that tax evasion takes two shapes: i) legal, or protected by the law and ii) fraudulent. He/She who reduces his/her taxable material in agreement with the law does not yet commit an illegal act. He/She only manages his/her business cleverly. But the fact that we use the term of legal “tax evasion”, besides the fact that it causes confusion between legal tax dodgers” and fraudulent tax dodgers”, makes us look at those who run their business cleverly as if they were criminals. We also unjustly apply this label to those who organize their business in offshore centers.
Viorel RO
Lex et Scientia , 2010,
Abstract: Taxes are the evil” in the absence of which the established companies cannot exist. The states need taxes in order to be able to fulfill the tasks for which they exist, and people – social beings by their nature – need states. But in their increasing need for revenues, states misuse the taxation right and the defense means of taxpayers for this purpose are limited. Between the need of the state for resources and the tax liabilities of taxpayers there must be a balance, its lack being injurious for both parties to the legal and tax report

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