The power factors and electronic thermal conductivities in bismuth telluride (Bi2Te3), lead-telluride (PbTe), and gallium arsenide (GaAs) at room temperature (300K) quantum wires and quantum wells are theoretically investigated. Our formalism rigorously takes into account modification of these power factors and electronic thermal conductivities in free-surface wires and wells due to spatial confinement. From our numerical results, we predict a significant increase of the power factor in quantum wires with diameter w=20 Ã…. The increase is always stronger in quantum wires than in quantum wells of the corresponding dimensions. An unconfined phonon distribution assumed based on the bulk lattice thermal conductivity is then employed to evaluate the possible enhancement of the thermoelectric figure of merit. The electronic thermal conductivity of a 20Ã… diameter wire and a 20Ã… layer thickness is found to be of no significant decrease. The resultant ZT, calculated for Bi2Te3, PbTe and GaAs, quantum wires and quantum wells, showed increase significantly. The additional thermoelectric figure of merit enhancement is mostly due to the two- and one-dimensional carrier confinement which lead to the enhancement of power factor.
The purpose of this interview study was to explore teachers’ perceptions of Response to Intervention (RtI) implementation in their school. Particularly, the study explored teachers’ knowledge of RtI, teachers’ perceptions of RtI their intervention/instruction in school, and teachers’ suggestions of RtI implementation in their school. The study design was a qualitative interview in nature and data were collected from face-to-face interviews with four teachers in one school. The findings revealed that RtI means to identify students’ problems; the positive teachers’ perceptions of their implementation included: (a) students who demonstrate progress through RtI are those who receive private education services, (b) progress monito
... Show MoreIn this paper, the effect of wear in the fluid film journal bearings on the dynamic behavior of rotor bearing system has been studied depending on the analytical driven of dynamic stiffness and damping coefficients of worn journal bearing. The finite element method was used to modeling rotor bearing system. The unbalance response, critical speed and natural frequency of rotor bearing system have been studied to determine the changes in these parameters due to wear. MATLAB software was used to find the analytical values of dynamic coefficients of journal bearing. The results of rotor mounted on fluid film journal bearings showed that the wear in journal bearing increases the amplitude of unbalance response and decrease critical speed, sta
... Show MoreOur main interest in this study is to look for soft semi separations axioms in soft quad topological spaces. We talk over and focus our attention on soft semi separation axioms in soft quad topological spaces with respect to ordinary points and soft points. Moreover study the inherited characteristics at different angles with respect to ordinary points and soft points. Some of their central properties in soft quad topological spaces are also brought under examination.
Human interferon as is the case in all kinds of interferon has complex effects but all share their impact on preventing the proliferation of viruses and preventing or reducing human Alantervjørn conversion occurs if the cell is in preventing the growth of the virus when interferon Balnmstqubl connects
Serum Creatine Kinase (SCK) activity was investigated in hyper
and hypqtbyroidim objects. Estimated Levels were compared with
healty controls.
Optimizat.im of SCK. activity has. been achieved using 0.95 mJ of
the Semtl.l and 25 m mol/L of -the subslratet creatitie phosphate . Reaction mixture was incubated at 37C for 1 0 minutes . Data obtained were r:cflects an elevation in the enzme activity in hyperthyroidism objec. Determination of the physical parameters (Vma-x and Km). were ol-,tained applying lit1eweaver- l3:urk Plot analysis. All detemi
... Show MoreNeutral and semi-synthetic hydrophilic polymers are widely used
in pharmaceutical technology to fomlUlate as controlled release drugs
delivery systems ,cellulose derivatives is biocompatibilily, biodegradability , non-toxicity, its is a good candidate as drug carrier. In this study, polymers were used as cellulose derivatives like Methylcellulose (MC) & Soditun Carboxymetl1ylcellulose (NaCMC) as hydrogels for controlled delivery for two kinds of drugs, Cefotaxine
& Amoxycill ine trihydrate i n different media (Distilled water, Normal Saline & Buffer solution PH=2). It has been shown that for sodium Carboxymethylcellulnse the drug release rate is more than the Mcthylcellulose and that the release
... Show MoreThe article considers a creolized text as a means of modern communication, describing its key verbal and visual components; the relationship of concepts polycode and creolized text has been shown; the universal basic image features have been called; the following kinds of creolized texts have been distinguished; it has been proved that the effective means of attracting the attention of the addressee is the use of expressive font features, which are divided into two groups: topographics (mechanisms of varying of areal syntagmatic of a text) and supragraphcs (change of typeface of font).
In a global context increasingly concerned with climate change, understanding the impact of economic growth on the environment is becoming crucial, especially for developing countries. Morocco has been committed to the United Nations Framework Convention on Climate Change (UNFCCC) to achieve the objectives set for reducing greenhouse gas (GHG) emissions by 13% by 2030, with 2010 as the reference year. Such a target could reach 32% by the same horizon under certain technical, financial and capacity building support conditions.
The main emitters of greenhouse gases (CH4 and CO2) are landfills because during the decomposition of solid waste CO2 is the most present gas pollutant is for this reason focuses this case study carried out in a
In this paper, the effects of hematocrit of red blood cells on blood flow through a stenosed human carotid artery was considered by taking blood as a Newtonian fluid. The governing equations on blood flow were derived. The mathematical content involved in the equations are the variables of interest such as number of stenosis , percentage of hematocrit of red blood cells in the blood, flow rate, wall shear stress, and viscosity of the blood. Guided by medical data collected on the constraint of blood flow in stenosed human carotid arteries, the governing equations were used to check the effects of pressure gradient, wall shear stress, velocity, and volumetric flow rate of blood in the human carotid arteries. Also, the one-dimensiona
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