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Representation of He-Ne laser irradiation effect on radish seeds with selected germination indices
S. Muszy？…？？ski,B. G？…？？adyszewska
International Agrophysics , 2008,
Abstract: In this paper the effect of He-Ne laser irradiation of radish seeds as a potential means to accelerate the germination rates have been investigated. We examined whether the change of final germination percentage (FGP) of irradiated seeds is accompanied by changes of other germination indices. Germination tests were carried out at the temperatures of 15 and 20oC, and the selected germination indices were: mean germination rate, mean germination time, relative frequency, time for the first seed to germinate, time to reach 50% germination, time between 25 and 75% and time between 10 and 90% of final germination. The results showed that He-Ne laser light irradiation could significantly affect the FGP when compared to the control seeds, although these depended on the germination temperature. The irradiation improves the FGP only at 20oC, although there were no differences detected in any other examined germination indices. The results led to the conclusion that irradiation did not affect any time-related properties describing the germination process. A simple comparison of the FGP of control and the irradiated seeds was found to be the only germination index which indicated the influence of He-Ne laser irradiation on germination.
Effect of storage time and temperature on Poisson ratio of tomato fruit skin
I. Kuna-Broniowska , B. G adyszewska , A. Ciupak
International Agrophysics , 2012, DOI: 10.2478/v10247-012-0006-x
Abstract: The results of studies investigating the effects of storage time and temperature on variations in Poisson ratio of the skin of two greenhouse tomato varieties - Admiro and Encore were presented. In the initial period of the study, Poisson ratio of the skin of tomato fruit cv. Admiro, stored at 13°C, varied between 0.7 and 0.8. After the successive 10 days of the experiment, it decreased to approximately 0.6 and was stabilized until the end of study. By contrast, the skin of tomatoes cv. Encore was characterized by lower values and lower variability of Poisson ratio in the range of 0.4 to 0.5 during storage. The examinations involving tomato fruit cv. Admiro stored at 21°C were completed after 12 days due to fruit softening and progressive difficulty with preparing analytical specimens. The value of Poisson ratio for both varieties stored at room temperature fluctuated throughout the experiment to approximate 0.5.
Analysis of Various Ventilation Systems Due to the Quality of Indoor Air in Educational Buildings？
Andrii Pushchinskyi,Katarzyna G？adyszewska-Fiedoruk,Vasyl Zhelykh
Proceedings | An Open Access Journal from MDPI , 2019, DOI: https://doi.org/10.3390/proceedings2019016029
Abstract: The quality of internal air is one of the factors that affect the pace and quality of knowledge acquisition. Therefore, it is important that the classrooms have high air quality. Using computer simulation, the effect of various building ventilation variants on air quality in classrooms was analyzed. As an indicator of air quality, the concentration of carbon dioxide in school halls was assumed
Physical assessment, spectroscopic and chemometric analysis of starch-based foils with selected functional additives
Agnieszka Niemczynowicz,Agnieszka Wójtowicz,Anna Oniszczuk,Arkadiusz Matwijczuk,Bo？ena G？adyszewska,Dariusz Karcz,Grzegorz Czernel,Janusz Podle？ny,Maciej Combrzyński,Tomasz Oniszczuk
- , 2019, DOI: 10.1371/journal.pone.0212070
Abstract:
Fourier Transforms of Tubular Objects with Spiral Structures  [PDF]
G. B. Mitra
Journal of Crystallization Process and Technology (JCPT) , 2012, DOI: 10.4236/jcpt.2012.24024
Abstract: Crystal structures of several naturally occurring minerals are known to contain various deformities such as cones, cylinders, and tapered hollow cylinders with different apex angles, which have been described as solid and hollow cones, “cups”, “lampshades” as well as rolled cylindrical planes. The present study was undertaken to determine how these different shapes within a crystal structure can be explained. Since the usual method of observing them is by either X-ray and electron diffraction or electron microscopy, we investigated Fourier transforms of these forms, which were considered in terms of spirals with varying radii. Three types of spirals were considered, namely: 1) Archimedean spiral; 2) Involute of a circle or power spiral and 3) Logarithmic spiral. Spiraling caused the radius r to be modified by a factor f(θ), so that r becomes rf(θ), where f(θ) = θ for Archimedean helix, θn for power helices like θ1/2 for Fermat’s helix, θ-1 for hyperbolic helix and eθ or e-θ for logarithmic helix, r and θ being co-ordinates of the map on which the helix has to be drawn, f(θ) is unaffected by the magnitude of r. Expressions have been derived that explain the diffraction of structures containing the distortions described above, and bring all of these phenomena under one “umbrella” of a comprehensive theory.
The Higher Dimensional Universe  [PDF]
B. G. Sidharth
Journal of High Energy Physics, Gravitation and Cosmology (JHEPGC) , 2016, DOI: 10.4236/jhepgc.2016.24051
Abstract: We examine how and under what conditions we encounter higher dimensions. This would be of relevance to, for example String Theory where indeed we come across higher dimensions.
On the Thermodynamics of a Two-Dimensional Electron Gas with Non-Parabolic Dispersion  [PDF]
G. Gulyamov, B. T. Abdulazizov
World Journal of Condensed Matter Physics (WJCMP) , 2016, DOI: 10.4236/wjcmp.2016.64028
Abstract: A thermodynamic density of states, electron density in the subband and the entropy of the gas as function of the temperature and the total two-dimensional electron density are studied. Semiconductor conduction band dispersion is described by the simplified Kane model. Numerical simulation shows that with an increase in the total electron concentration, thermodynamic density of states at low temperatures changes abruptly and smoothes jumps at high temperatures. This change manifests itself in the peculiar thermodynamic characteristics. The results are used to interpret existing experimental data.
Role of Metallic Nanofillers on Mechanical and Tribological Behaviour of Carbon Fabric Reinforced Epoxy Composites  [PDF]
G. S. Divya, B. Suresha
Materials Sciences and Applications (MSA) , 2018, DOI: 10.4236/msa.2018.99054
Abstract: In this study, hybrid composites based on carbon fabric and epoxy (C/Ep) were fabricated by hand lay-up method followed by compression moulding. The C/Ep with optimum carbon fiber (60 wt%) was chosen as a reference material, and to it, the metallic nanoparticles like aluminum (Al) and zinc (Zn) of different wt% (0.5 and 1.0) were included as secondary fillers. To understand the synergism effect of these hybrid reinforcements, mechanical properties and tribological behavior of composites were studied. From the test results, it was proved that hybridization improved the mechanical and tribological properties. The C/Ep consisting of 0.5 wt% Zn and Al showed higher tensile properties in comparison with all other fabricated composites. Increase in flexural strength and flexural modulus also observed as the filler content increased in C/Ep composite. Higher impact strength is noted at 1 wt% Zn filled C/Ep composite. Wear test data revealed that 0.5 wt% Zn in C/Ep has got superior wear resistance. Wear mechanisms were discussed using scanning electron micrographs of selected worn surfaces of the composites.
Innovation Clusters Effects on Adoption of a General Purpose Technology under Uncertainty  [PDF]
B. G. Jean Jacques Iritié
Theoretical Economics Letters (TEL) , 2018, DOI: 10.4236/tel.2018.814184
Abstract: This paper analyzes the effect of innovation clusters on the adoption of a general purpose technology (GPT) and on firms R&D investment levels in imperfect information situation. We developed a theoretical model of vertical relation, described as a four-step game between an upstream firm providing innovative GPT and an innovative downstream associated sector, integrator of this technology. The downstream sector ignores the quality of the GPT and we model the innovation cluster as a coordination mode of firms, improving the probability of the downstream firm to receive information about the quality of the GPT technology. Then, we determine firms equilibria (i.e. prices and technological qualities) and we showed that the effect of innovation clusters on the choice of qualities, the adoption behavior, levels of R&D investment as well as that social welfare depends on the quality of R&D activities carried out before the establishment of the clusters and a threshold effect (i.e. cluster critical mass); if the critical mass in terms of information sharing and interaction is not reached, the cluster may have negative effects. In other words, the consensual idea of expected positive effects of innovation clusters must be put into perspective.
Les aspects productifs de l'économie informelle: recherche des indicateurs pour une réponse au développement en Afrique
B. B. G. Muheme
Afrika Focus , 1992,
Abstract: This article aims at deepening our understanding of the concept informal economy.It is the case that definitions with regard to the reality of this phenomenon vary in function of the author and the countries studied. Indeed, the concept needs to be discussed right across the countries of the West, the East European countries under the old system, i.e. until 1990, and the countries of Africa.With regard to the informal economy in Africa, the characteristics of irrationality and the lack of initiative on the part of economic agents has often been posited.However, this economic phenomenon is neither exclusive to Africa nor is it confined to the present time. Only a comparative approach will enable one to arrive at some precision with regard to the concepts used in the economic literature.Our primary goal is to place this informal economy within the global perspective of African development. This informal economy sets itself up as a creative attempt, often able to give efficient answers, whether in the field of agriculture or in other forms of activity, to the challenges of badly mismanaged societies.
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