Coffee is the most essential drink today, aside from water, the high consumption of coffee and the byproducts of its soluble industries such as spent coffee grounds can have a negative effect on the environment as a source of toxic organic compounds. Therefore, caffeine removal from the spent coffee ground can be applied as a method to limit the effect of its production on the environment. The aim of this study is to determine the kinetics and thermodynamics parameters and develop models for both processes based on the process parameters by using traditional solid-liquid extraction and Ultrasound-assisted extraction methods. The processes were performed at a temperature range of 25 to 55 °C for traditional and ultrasound baths, and experimental time ranged from 5- 60 min. The results demonstrated that under the above conditions, the extraction process applies to the pseudo-first-order reaction, where the rate constant K value increases with temperature. The transition state parameters were also discussed where these parameters indicated that the system of the process exhibited an activated complex formation state resulting in a thermodynamically unfavorable process, and the thermodynamic parameters at the equilibrium state were also evaluated in terms of the obtained yield percentage. The results also showed that the ultrasound-assisted bath process showed a spontaneous behavior at temperatures of 45 °C and 55 °C with D°G of -1192.9703 and - 2725.25 J/mole. On the other hand, for the traditional method, the extraction process was approaching a spontaneous behavior with the temperature increasing where at 25 °C the D°G value was 10379.944 J and at a temperature of 55 °C it reached 8004.26 J/mole.
One of the most demanded studies is wind turbine site assessment. It is difficult to build a simulation program because of the many variables that affect the wind speed and direction. The procedure of this research depend on two approaches, the Wind Atlas Analysis model and the Inverse Distance Wait interpolation. These procedures give the estimated annual energy production for each turbine (V82) with 82m blades diameter at 70m hub heights. The output at this location for each turbine is about (4.3 GWh). The studied area is about 20x20km2 and could be plant at least 600 turbine and have about 2500 GWh of annual energy production.
The appliance of milligauss meter was designed by Qusay Ismail to measure the induce of electromagnetic field for home appliance which are put at a distance from milligauss meter (15-30-60)cm .The results showed some appliance has recorded higher than normal acceptable level of electromagnetic radiation emissions and produced radiation of (350650)milligauss as for the rest of appliances has recorded values which are ranged between (1200)milligauss ,laptop was recorde radiation generally lower than from desktop and computer moniter (CRT).The radiation ,intensity decrease with increasing distance.
Equilrium, kinetic and mechanistic studies for thcoordination of
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some amino acids "'AA'1
glycine, alanine, .a:ncl histidine, to Cr (Ill)
center of trans .[Cr(ox}2(B.2 0hr {TJ'} cornplein monderarely acidic
range ofpH=4.8-6-.7 ( p =Q.4M NaN03) are reported. The equili rium
c.onsta:nts at 25°C .were found logKequ.=4.95J ,5.206and5.128for glycine, alap.ine, md
... Show MoreRefrigerant R134a has been widely utilized in automotive air conditioning systems (AACSs); R134a has a high global warming potential (GWP) of 1430 despite having zero ozone depletion potential (ODP). Coming refrigeration systems must include refrigerants with low GWP and zero ODP. The aim of this experimental study is to evaluate the thermal performance of an (AAC) with different values of compressor speeds, i.e., (1000, 1700, and 2400 rpm) and two thermal loads, i.e., (500 and 1000 Watt) with the absence and presence of liquid suction heat exchanger (LSHX) using R134a. The results showed that adding LSHX enhanced the COP cycle by 7.18%, 10.7%, and 3.09% for the first, second, and third speed, respectively, at 500 Watt, while the en
... Show MoreBackground: Masseter muscle is one of the most obvious muscles of mastication and considered as one indicator of jaw muscle activity. It has a major influence on the transverse growth of the midface and the vertical growth of the mandible. This study undertaken to determine the role of cephalometric analysis for discrimination between Cl I and Cl III skeletal relationships, determine the role of ultrasonography in determination of masseter muscle thickness, compare masseter muscle thickness between Cl I and Cl III skeletal relationships, and determine the effect of gender on masseter muscle thickness. Material and Method: The sample of the current study consisted of 70 Iraqi subjects 40 males and 30 females with age ranging 18-25 years. The
... Show MoreThe heavy metal cadmium is extremely harmful to both humans and animals. Zinc supplementation protects the biological system and reduces cadmium-induced toxicity. This study aimed to determine whether zinc chloride (ZnCl2) could protect male mice with the damaged liver induced by cadmium chloride (CdCl2). The protective role of zinc chloride and expression of the metallothionein (MT), Ki-67, and Bcl-2 apoptotic proteins in hepatocytes were studied after subchronic exposure of mice to cadmium chloride for 21 days. Thirty male mice were randomly categorized into 6 groups (5 mice/group) as follows: a control group that did not receive any treatment, a group given ZnCl2 at 10 mg/kg alone, and two groups received ZnCl2 (10 mg/kg) i
... Show MoreThe Boltzmann transport equation is solved by using two- terms approximation for pure gases . This method of solution is used to calculate the electron energy distribution function and electric transport parameters were evaluated in the range of E/N varying from . 172152110./510.VcmENVcm
From the results we can conclude that the electron energy distribution function of CF4 gas is nearly Maxwellian at (1,2)Td, and when E/N increase the distribution function is non Maxwellian. Behavior of electrons transport parameters is nearly from the experimental results in references. The drift velocity of electron in carbon tetraflouride is large compared with other gases
The crystal compounds Tl2-xAg2-ySryBayCa2Cu3O10+& are successfully prepared in different concentrations (x, y=0.1, 0.2, 0.3, 0.4, 0.5) by solid state reaction process. The samples were then subjected to Nano technique under hydrolic pressure 8 ton/cm2. samples have been annealed in (850 C0) for 72 hours. The results show a best value at x, y=0.3 ratio of Ag, Ba. Electrical resistivity at x, y= 0.3 of Ag, Ba are obtained when the best value of Tc= 141 K. Samples morphology were also observed by AFM (in three dimensions), the best value of Nano is 91.74 nm at x, y= 0.3. Morphological structures of the surface were also observed by (SEM) and (EDX) show that there are dark regions and light which indicate the presence of heavy elements a
... Show MoreBackground: The bonded orthodontic retainer constructed from multistrand wire and composite is an efficient esthetic retainer, which can be maintained long-term. Clinical failures of bonded orthodontic retainers, most commonly at the wire/composite interface, have been reported. This in vitro investigation aimed to evaluate the tensile forces of selected multistrand wires and composite materials that are available for use in the construction of bonded fixed retainers. Materials and Methods: The study sample includes 120 wires with three types of retainer wires (3 braided strands\ Orthotechnology, 8 braided strands\ G&H Orthodontics, 6 coaxial strands\ Orthoclassic wires), two types of adhesive (flowable\ Orthotechnology, non flowable\ G&H O
... Show MoreIn this research, the study effect of irradiation on structural and optical properties of thin film (CdO) by spray pyrolysis method, which deposited on glasses substrates at a thickness of (350±20)nm , The flow rate of solution was 5 ml/min and the substrate temperature was held constant at 400˚C.The investigation of (XRD) indicates that the (CdO) films are polycrystalline and type of cubic. The results of the measuring of each sample from grain size, micro strain, dislocation density and number of crystals the grain size decreasing after irradiation with gamma ray from(27.41, 26.29 ,23.63)nm . The absorbance and transmittance spectra have been recorded in the wavelength range (300-1100) nm in order to study the optical properties.
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