Preferred Language
Articles
/
ijcpe-346
ESTIMATION OF MASS TRANSFER COEFFICIENTS IN A PACKED DISTILLATION COLUMN USING BATCH MODE
...Show More Authors

This research adopts the estimation of mass transfer coefficient in batch packed bed distillation column as function of physical properties, liquid to vapour molar rates ratio (L / V), relative volatility (α), ratio of vapour and liquid diffusivities (DV / DL), ratio of vapour and liquid densities (ρV / ρL), ratio of vapour and liquid viscosities (μV/ μL).
The experiments are done using binary systems, (Ethanol Water), (Methanol Water), (Methanol Ethanol), (Benzene Hexane), (Benzene Toluene). Statistical program (multiple regression analysis) is used for estimating the overall mass transfer coefficient of vapour and liquid phases (KOV and KOL) in a correlation which represented the data fairly well.

KOV = 3.3 * 10-10 α-0.7 (DV / DL) 0.65 (L / V) 3.5 (ρV / ρL) 1.25 (μV / μL) -5.0

KOL = 2.8 * 10-6 α-0.95 (DV / DL) 0.03 (L / V) 1.15 (ρV / ρL )0.077 (μV / μL) -0.9

In this research a method where the resistances to mass transfer in both phases are accounted for separately through the use of HTU-NTU model for each phase

Z=HTUOV.NTUOV and Z=HTUOL.NTUOL

Results show that both overall vapour and liquid mass transfer coefficient are increased with liquid to vapour molar rates ratio, vapour to liquid diffusivities ratio and vapor to liquid densities ratio, but decreased with increasing the relative volatility and vapour to liquid viscosities ratio.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Feb 17 2019
Journal Name
Iraqi Journal Of Physics
A Study of the electronic structure of CdS Nanocrystals using density functional theory
...Show More Authors

Density Functional Theory at the generalized-gradient approximation level coupled with large unit cell method is used to simulate the electronic structure of (II-VI) zinc-blende cadmium sulfide nanocrystals that have dimensions 2-2.5 nm. The calculated properties include lattice constant, conduction and valence bands width, energy of the highest occupied orbital, energy of the lowest unoccupied orbital, energy gap, density of states etc. Results show that lattice constant and energy gap converge to definite values. However, highest occupied orbital, lowest unoccupied orbital fluctuates indefinitely depending on the shape of the nanocrystal.

View Publication Preview PDF
Crossref
Publication Date
Wed Dec 25 2019
Journal Name
Journal Of Engineering
Link Failure Recovery for a Large-Scale Video Surveillance System using a Software-Defined Network
...Show More Authors

The software-defined network (SDN) is a new technology that separates the control plane from data plane for the network devices. One of the most significant issues in the video surveillance system is the link failure. When the path failure occurs, the monitoring center cannot receive the video from the cameras. In this paper, two methods are proposed to solve this problem.  The first method uses the Dijkstra algorithm to re-find the path at the source node switch. The second method uses the Dijkstra algorithm to re-find the path at the ingress node switch (or failed link).

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Apr 30 2022
Journal Name
Iraqi Journal Of Science
Comparison Different Estimation Method for Reliability Function of Rayleigh Distribution Based On Fuzzy Lifetime Data
...Show More Authors

    In this study, we present different methods of estimating fuzzy reliability of a two-parameter Rayleigh distribution via the maximum likelihood estimator, median first-order statistics estimator, quartile estimator, L-moment estimator, and mixed Thompson-type estimator. The mean-square error MSE as a measurement for comparing the considered methods using simulation through different values for the parameters and unalike sample sizes is used. The results of simulation show that the fuzziness values are better than the real values for all sample sizes, as well as  the fuzzy reliability at the estimation  of the Maximum likelihood Method, and Mixed Thompson Method perform better than the other methods in the sense of MSE, so that

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Mon Jul 01 2024
Journal Name
Alexandria Engineering Journal
Comparison of some Bayesian estimation methods for type-I generalized extreme value distribution with simulation
...Show More Authors

The Weibull distribution is considered one of the Type-I Generalized Extreme Value (GEV) distribution, and it plays a crucial role in modeling extreme events in various fields, such as hydrology, finance, and environmental sciences. Bayesian methods play a strong, decisive role in estimating the parameters of the GEV distribution due to their ability to incorporate prior knowledge and handle small sample sizes effectively. In this research, we compare several shrinkage Bayesian estimation methods based on the squared error and the linear exponential loss functions. They were adopted and compared by the Monte Carlo simulation method. The performance of these methods is assessed based on their accuracy and computational efficiency in estimati

... Show More
View Publication
Scopus (2)
Scopus Clarivate Crossref
Publication Date
Sun Dec 01 2019
Journal Name
Indian Journal Of Ecology
Evaluation of maize hybrids, their inbred lines and estimation of genetic divergence based on cluster analysis
...Show More Authors

Scopus (3)
Scopus
Publication Date
Sun Dec 29 2019
Journal Name
Iraqi Journal Of Science
Estimation of Average of Global Solar Radiation Depending on Sunshine Duration Hours for Iraqi Metrological Stations
...Show More Authors

In this study, the global solar radiation for the locations of fourteen Iraqi metrological stations was studied and calculated. This was performed because most of the Iraqi stations lack solar radiation measuring devices. The equation postulated by Angström (1924) and modified by Prescott (1940) was utilized for the estimation of the solar radiation for the fourteen Iraqi metrological stations depending on sunshine duration measurements of these stations. Empirical constants of Angstrom-Prescott equation that are adopted by the Food and Agriculture Organization (FAO) were used for obtaining the results. The utilized data reported in this study were taken from the Republic of Iraq Meteorological Office (RIMO). The calculations and diag

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Dec 01 2020
Journal Name
Gulf Economist
The Bayesian Estimation in Competing Risks Analysis for Discrete Survival Data under Dynamic Methodology with Application to Dialysis Patients in Basra/ Iraq
...Show More Authors

Survival analysis is one of the types of data analysis that describes the time period until the occurrence of an event of interest such as death or other events of importance in determining what will happen to the phenomenon studied. There may be more than one endpoint for the event, in which case it is called Competing risks. The purpose of this research is to apply the dynamic approach in the analysis of discrete survival time in order to estimate the effect of covariates over time, as well as modeling the nonlinear relationship between the covariates and the discrete hazard function through the use of the multinomial logistic model and the multivariate Cox model. For the purpose of conducting the estimation process for both the discrete

... Show More
View Publication Preview PDF
Publication Date
Sun Sep 06 2009
Journal Name
Baghdad Science Journal
Estimation of cellular immune response by evaluation of some cytokines in immunopathogenesis of chronic hepatitis B and C pre- and post- treated Iraqi patients (in vivo and in vitro)
...Show More Authors

Two groups of chronic hepatitis B and C virus patients were divided into Pre-treated patients (25 CHB patients with positive HBs Ag for more than 6 months and 40 CHC patients), and post-treated patients [12 CHB patients (4, 6, and 2 were treated with lamivudine, IFN-? and combination of LMV + IFN-? respectively), and 27 patients for CHC (3, 13 and 11 patients were treated with Ribavirin, IFN-? and combination therapy (RBV+ IFN-?) respectively].These patients were followed up for 6 months. By using ELISA technique, levels of IL-6, IL-10, IFN-? and TNF-? were measured in vivo and in vitro (supernatant of PBMCs stimulated with PHA) and compared with healthy control. The mean level of IL-6, IL-10 and TNF-? in CHB patients showed significant dif

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 23 2021
Journal Name
Iraqi Journal Of Science
Using and Evaluating the Efficiency of GRIMs Model in Making Some Simulations of Weather Variables in Three Countries in Middle East: A Snowfall Case Study
...Show More Authors

    Predicting weather by numerical models have been used extensively in research works for Middle East, mostly for dust storms, rain showers, and flash floods with a less deal of interest on snow precipitation. In this study, the Global/Regional Integrated Model System (GRIMs) that was developed in South Korea was used to predict a rare snowfall event occurred in three countries in Middle East (Syria, Jordan and Iraq) located between (25-65 oE; 12-42 oN) in year 2008. The main aim of this study was to test GRIMs efficiency, which would be used for the first time in Middle East, to make predictions of weather parameters such as pressure, temperature, and relative humidity especially in the selected ar

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Thu Aug 04 2022
Journal Name
Journal Of Nanomaterials
Thermal Management of the Melting Process in a Latent Heat Triplex Tube Storage System Using Different Configurations of Frustum Tubes
...Show More Authors

In this study, the energy charging mechanism is mathematically modeled to determine the impact of design modifications on the thermofluidic behavior of a phase change material (PCM) filled in a triplex tube containment geometry. The surface area of the middle tube, where the PCM is placed, is supported by single or multi-internal frustum tubes in vertical triplex tubes to increase the performance of the heating and cooling of the system. In addition to the ordinary straight triplex tubes, three more scenarios are considered: (1) changing the middle tube to the frustum tube, (2) changing the inner tube to the frustum tube, and (3) changing both the internal and central tubes to the frustum tubes. The impact of adopting the tube desig

... Show More
View Publication
Scopus (33)
Crossref (26)
Scopus Clarivate Crossref