The fluctuation and expansion ratios have been studied for cylindrical gas-solid fluidized columns by using air as fluidizing medium and Paracetamol as the bed material. The variables were the column diameter (0.0762, 0.15, and 0.18 m), static bed height (0.05, 0.07, and 0.09 m), and air velocity to several times of minimum fluidization velocity. The results showed that both the fluctuation and expansion ratios had a direct relation with air velocity and an inverse one with column diameter and static bed height. A good agreement was between the experimental results and the calculated values by using the correlation equations from the literature.

  The influence of annealing on quaternary compound Ag0.9Cu0.1InSe2 (ACIS) thin film is considered a striking semiconductor for second-generation solar cells. The film deposited by thermal evaporation with a thickness of about 700 nm at R.T and vacuum annealing at temperatures (373,473) K for 1 hour. It was deposited in a vacuum of 4.5*10-5 Torr on a glass substrate. From XRD and AFM analysis, it is evident that Ag0.9Cu0.1InSe2 films are polycrystalline in nature, having ideal stoichiometric composition. Structural analysis indicated that annealing the films following the deposition resulted in the increasing polycrystalline phase with the preferred orientation along (112) direction. , increasing crystallite size and average grain size

This study was conducted according to contract with the North Refineries Company-Baiji and deals with the hydrodesulphurization of vacuum gas oil of Kirkuk crude oil, boiling range 611-833 K. A trickle bed reactor packed with a commercial cobalt-molybdenum on alumina catalyst was used. The operating conditions were: temperature range 583-643 K, liquid hourly space velocity range 1.50-3.75 1/h, hydrogen to oil ratio about 250 l/l and pressure kept constant at 3.5MPa.
The results showed that the aromatic content decreased and sulfur removal increased with increasing temperature and decreasing space velocity. The properties (viscosity, density, flash point and carbon residue) of the products decrease with temperature increasing, but the

In this study NiO - CoO bimetallic catalysts are prepared with two Ni/Co ratios (70:30 and 80: 20) using the precipitation method of nitrate salts. The effects of Ni /Co ratio and preparation methods on the catalyst are analyzed by using different characterization techniques, i.e. atomic absorption (AA) , XRD, surface area and pore volume measurements according to the BET method . The results indicate that the best catalyst is the one containing the percentage of Ni :Co ( 70 : 30 ). Experiments indicate that the optimal conditions to prepare catalyst are stirring for three hours at a temperature of 60oC of the preparation , pH= (8-9) , calcination temperature at 400oC for two hours

Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60 test block w

Background: Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60

The coma gasses consist of molecules liberated from the nucleus by solar heating and relative sublimation. Once they have left the nucleus, these molecules in the coma are exposed to direct solar radiation and can be damaged in various ways due to the combined action of these reactions.

   One of some complex problems facing the research in this field is that the Maxwell-Boltzmann equation gives distribution function for one kind of particles which have same masses, but the gas has multi-groups of particles (Carbon, Neon, Sodium … etc.), where all these components must be in one program to extract average velocity of all and calculate particles velocity to each band. This problem is solved here by Matlab program a

In this work, polyvinylpyrrolidone (PVP), multi-walled carbon nanotubes (MWCNTs) nanocomposite was prepared and hybridized with Graphene (Gr) by the solution casting method.  The morphological and electrical properties were investigated by field effect scanning electron microscopy (FESEM) images, portraying a uniform dispersion of graphene within the PVP-MWCNT nanocomposite. The AC conductivity increased from (1.45552) to (2.34812) (Ω cm)^-1 with the use of nanocomposite. The increasing continues for the AC conductivity after hybridized with graphene up to (7.20641) (Ω cm)^-1. In addition, the performances of the prepared samples for gas sensor application have been investigated.

The main objective of" this paper is to study a subclass of holomrphic and univalent functions with negative coefficients in the open unit disk U= defined by Hadamard Product. We obtain coefficients estimates, distortion theorem , fractional derivatives, fractional integrals, and some results.