Adsorption and ion exchange are examples of fixed-bed sorption processes that show transient behavior. This means that differential equations are needed to design them. As a result, numerical methods are commonly utilized to solve these equations. The solution frequently used in analytical methods is called the Thomas solution. Thomas gave a complete solution that adds a nonlinear equilibrium relationship that depends on second-order reaction kinetics. A computational approach was devised to solve the Thomas model. The Thomas model's validity was established by conducting three distinct sets of experiments. The first entails the adsorption of acetic acid from the air through the utilization of activated carbon. Following this, zeolite-5A adsorbs trichloroethylene (TCE) from the air. Finally, activated carbon is employed for the purpose of adsorbing o-cresol from aqueous solutions. A study was done to estimate phase equilibria and interphase mass transfer rates. To find the kinetic mass-transfer coefficient (K) for gases, the phase coefficients for mass transfer in the fluid phase ( ) and the pore phase ( ) were added together. The estimation of (K) for liquid was performed using the mass transfer coefficient for the solid phase and togather. The results suggest that the adsorption of acetic acid from air on activated carbon gives a good agreement with the Thomas model. The other sets of data demonstrate a disparity due to the underlying assumptions inherent in the Thomas model.
The study was conducted to evaluate the antibacterial activity of water and alcoholic extracts (cold and hot) of plant Zingiber officinale against different types of bacteria includeing (Staphylococcus aureus ، Staphylococcus epidermis ، Escherichia coli ، Pseudomonas aeruginosa
ØŒProteus spp.and Klebsilla pneumoniae). High effect of the hot (water and alcoholic) extracts of plant Zingiber officinale was on the different types of bacteria. Investigation of presence of active compounds (Alkaloids, Glycoside, Tannins, Saponine and Resine) in this plant parts was carried out. Sensitivity test of the isolate
Recent developments in two main phases of cumulus cloud studies are discussed; first the relations between the clouds and their energy sources in the subcloud layer and second, the interaction between the clouds and their environment in the cloud layer. Under the first heading, the various originating impulses for cumulus formation are mentionitd. and how the character of this impulse affects the spacing, scale and temperature structure of the clouds. The possible origins of trade cumuli are considered.
Abstract
The multiple linear regression model of the important regression models used in the analysis for different fields of science Such as business, economics, medicine and social sciences high in data has undesirable effects on analysis results . The multicollinearity is a major problem in multiple linear regression. In its simplest state, it leads to the departure of the model parameter that is capable of its scientific properties, Also there is an important problem in regression analysis is the presence of high leverage points in the data have undesirable effects on the results of the analysis , In this research , we present some of
... Show MoreTwelve stations in the cities of Kufa and Mishkhab were selected for studying the geotechnical, including physical, engineering, chemical and mineralogical, properties of soils in the river banks along the Euphrates River. Grain size distribution of the bank soils showed higher silt than clay and sand percentages. Soil samples from the 12 stations were classified according to the USCS standards. Silt with low plasticity constituted 91% of the silt fraction, whereas that with high plasticity composed 9%. The saturated density values ranged between 1.75-2.073 g/cm3 with an average of 1.953 g/cm3, while the dry density values ranged between 1.307-1.740 g/cm3 with an average of 1.553 g/cm3. The val
... Show MoreSmoking has multiple effects on sex hormone , some of which are associated with important clinical implication .The present study was undertaken to investigate the biochemical changes of sex hormones associated with long standing cigarette smoking in 40 heavy smokers comparing with non- smoker and to correlate it with BMI for each .The sex hormones levels were determined by RIA technique . Atomic absorption technique was used to measure the zinc levels. The serum testosterone and estrogen levels of non – smoker group were 17.775ng\ml and 38.65ng\ml at p< 0.05, respectively .While the serum testosterone and estrogen levels of smoker group were 17.615n
... Show MoreThe parasite E.histolytica was first isolated from a stool sample, and then cultivated and maintained in vitro using Locke-egg medium (LEM) and Liver infusion agar medium (LIAM) . Then, the effect of some types of erythrocytes (human and sheep), on the growth and activity of the parasite in the two culture media was investigated. The parasite was able to ingest and lysis erythrocytes of human and sheep that were supplemented to the culture media and such manipulation was able to augment the reproduction rate of the cultivated E. histolytica, however, such consequence was media- and concentration-dependent. The reproduction rate was significantly increased (66.0, 57.5 and 58.6%, respectively) in LEM medium containing human erythrocytes ty
... Show MoreBackground: Porcelain veneers are under a great deal of stress which may lead to clinical failure as fracture or dettachment. This study examined whether different finishing lines and lingual shoulder preparations in the incisal area of the maxillary central incisor affect the bond of the porcelain veneers. Materials and methods: A two- dimensional finite element model was made. Location and magnitude of maximum Von Mises stresses were calculated in porcelain veneer. Six types of preparations were drawn as:incisal overlap of 0.5mm, 1mm and 1.5mm depth and lingual shoulder, and incisal overlap of 0.5mm, 1mm and 1.5mm depth without shoulder preparation. Results: Stress formation is maximum in the incisal edge region. All the lingual shoulder
... Show MoreThe aim of the research is to reveal the reality of teacher performance evaluation in the Sultanate of Oman in light of some global models. The study followed a qualitative descriptive research design. Seven forms of teacher formative and summative assessments were analyzed. Besides, an analytical template was developed, consisting of six areas related to the teaching performance of teachers. These included: lesson planning and preparation, learning environment, education, professional development, student academic, and community and parental partnership. The study reached a number of results; the most notable is the lack of change of forms for more than a decade despite the rapid development of the educational system in the sultanate in
... Show MoreThe present study aims to identifying the effect of Eurygaster integriceps infection on the quality features of the local wheat varity IBA 99. The result revealed significant decrease in the percentage of protein of infected wheat at (4, 5)% compared to sound wheat values for the sound wheat were (10.9%) whereas those for the infected wheat were(9.0, 8.4 )% also the result revealed significant increased in the percentage of ash in the infected wheat flour. The result showed significant decrease in the percentage of wet and dry gluten in the infected wheat by sun bug at the rate of (2, 3, 4, 5)% compared to sound wheat value (27, 9% and 25, 23, 22, 22, 20%) for wet gluten and (8.2, 7.8, 7, 7.2, 6%) for dry glutin . The value of sedimentati
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