Metamaterial perfect absorber is very important in the study of refractive index sensor. The time domain finite difference method is used to simulate the surface plasmon structure. The double nanorod periodic structure is designed, and the parameters of the top layer structure are optimized according to the impedance matching principle, and the absorption rate of the structure to the light wave reaches 99.6% when the wavelength is about 12 mm. The absorption spectroscopy of the structure is studied with the change of the refractive index of the spatial medium around the structure, and the sensitivity of the double nanorod structure is 4,008 nm/RIU, which can be used to measure the refractive index of the gas.
This work presents the results of the continuity of the research process carried out in the Energy Studies Center belonging to the Faculty of Technical Sciences of the University of Matanzas, which involves the establishment of a dimensionless model to determine the average condensation heat transfer coefficient of Air Coleed Condenser (ACC) systems in straight and inclined tubes. The research consists in obtaining in an analytical way the solution of the differential equation of the velocity profile, considering that condensation is of pellicular type, finally the empirical condition of Roshenow is combined with the theoretical solution to generate a numerical expression that allows obtaining with a 15.2% of deviation in 2,192 tests, a value of the average coefficient of heat transfer by condensation very similar to the one obtained with the use of the most referenced model in the consulted literature, the empirical model of Chato.
Embassies are important buildings, involving the diplomatic image of a country’s government in another foreign country. Given the rising tensions between countries, either political, economic, religion or war, attacks on embassies have been increasing in recent years. Thus, it is evident that appropriate measures are to be taken to reduce the potential impact of an attack. The paper discusses the measures in enhancing building security of embassies. The principles for Security Planning and Design are discussed, followed by an introduction to a systematic security risk assessment framework. The framework is evaluated regarding the potential security risk posed by an attack against elements of the mega infrastructure using explosives. Further options to increase the security of embassies are also explored to reduce the risk of a potential attack. A security-enhanced building, planned and constructed well to specifications, can provide benefits to the client, including greater cost advantage and increase of value for the structure.
The management of Mediterranean mountains need to know whether or not the flora is adapted to respond to fire and, if so, through what mechanisms. Serpentine outcrops constitute particular ecosystems in the Mediterranean Basin, and plants need to make an additional adaptive effort. The objective of this study is to know the response to fire of the main members of the group of serpentine plants, which habit the Spanish Mediterranean ultramafic mountain, to help in their management. For this purpose, monitoring plots were established on a burned ultramafic outcrop, which was affected by fire in August 2012.They were located in the Mediterranean south of the Iberian Peninsula, Andalusia region. The dominant vegetation of this serpentine ecosystem had been studied previously to fire; it was a shrubland composed of endemic serpentinophytes (small shrubs and perennial herbs) included in Digitali laciniatae-Halimietum atriplicifolii plant association (Cisto-Lavanduletea class) in an opened pine forest. The post-fire response of the plants was studied in the stablished burned plots by field works through permanent 200 x 10 m transect methods, consisting on checking whether they were resprouters, seeders, both of them or if they showed no survival response. Additional information about fire related functional traits is provided for the studied taxa from other studies. Of the total of plants studied (23 taxa), 74% acted as resprouters, 30% as seeders, some of which also had the capacity to resprout (13%), and only 9% of the plants did not show any survival strategy. The presence of a resprouting burl was not high (17%), although serpentine small shrubs such as Bupleurum acutifolium and the generalist Teucrium haenseleri had this kind of organ. The herbaceous taxa Sanguisorba verrucosa, Galium boissieranum and Linum carratracense were seen to be resprouters and seeders. The serpentine obligated Ni-accumulator, Alyssum serpyllifolium subsp. malacitanum, did not show any survival strategy in the face of fire and therefore their populations need monitoring after fires. In the studied ecosystems no species had traits that would protect the aerial part of the plant against fire, although most of the species are capable of post-fire generation by below ground buds. Our results show that the ecosystem studied, composed of taxa with a high degree of endemism and some of them threatened, is predominantly adapted to survival after a fire, although their response capacity may be decreased by environmental factors.
This report deals synthesis of CuInGa (CIG) nano materials along with doctor blade and spin coated thin films selenization and their physical properties. The doctor blade and spin coated CIGS/SLG thin films thicknesses are obtained ̴ 2 μm and ̴ 2.95 μm. Raman spectroscopy of these thin films leads the chalcopyrite phase formation by exhibiting the peak at wave number 171 cm-1. The well developed grain growths of spin coated thin film are appeared in the surface morphology. While the grain growths developments in doctoral blade coated thin film is rather hard and fuzzy. EDS measurement recognised the existence of the compositional ratio presence of the alloying elements Cu, In. Ga and Se. The doctor blade and spin coated CIGS/SLG thin films are exhibited the UV- Visible transmission peak in the wave length range 240 nm 320 nm. The optical energy band gaps for the doctor blade and spin coated CIGS thin films are obtained 1.41eV and 1.5 eV.
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