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Electrowinning of Copper Using Rotating Cylinder Electrode Utilizing Lead Anode

Engineering（科研） 2011年第4期3卷 340-358页

作者： Hesham Soliman ahmed abd El-Moneim 不详

The effect of lead anode, rotating cylinder electrode (RCE), amount of 1,2-dihydroxypropane (12-DHP), temperature and rotation on the electrowinning of copper from low concentration acidified copper sulphate solution has been investigated. Copper powder was electrodeposited onto RCE that made of pure copper. From cyclic voltammetry experiments, an empirical parameter called the departure percent, S, was obtained which may represent the stability of the organic additive in the given medium and under the experimental conditions. The inhibition percentage, P, was 0.00 - 89.91% depending on the experimental variables. P was affected by temperature and mole fraction of 12-DHP, while rotation did not show any influence on it. Values of activation energy of electrodeposition process, Ea, were found to be less than 28 kJ mol-1 indicating diffusion controlled process. The overall mass transfer correlations under the present conditions have been computed using the dimensional analysis method. The data were valid for 90 < Sh < 1098, 737 < Sc < 59284 and 271 < Re < 7046 and the results agreed with the previous studies of mass transfer to rotating cylinders in turbulent flow regimes. The effect of time, content of 12-DHP, temperature and the speed of rotation on the morphological changes of the electrodeposited copper powder as well as deposits composition and crystallite size have been studied. Various crystallite sizes ranged 7.1 nm - 250.6 nm were obtained and characterized by EDS and XRD. Different topographs proved that the rate of copper electrodeposition increased by increasing deposition time, temperature and the speed of rotation. Also, they proved that the deposition rate decreased by adding 12-DHP to the solution. Therefore, the results obtained by SEM supported those achieved by measuring the limiting current density and follow the normal manner when organic solvents were added to the electrodeposition bath.

关键词： Electrodeposition Electrowinning Lead Anode Rotating Cylinder Electrode (RCE) 1 2-Dihydroxypropane (12-DHP) Copper Powder

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Integration of Multi-Constellation GNSS Precise Point Positioning and MEMS-Based Inertial Systems Using Tightly Coupled Mechanization

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Positioning 2015年第4期6卷 81-95页

作者： Mahmoud abd Rabbou ahmed El-Rabbany Department of Civil Engineering Ryerson University Toronto Canada

We develop a new integrated navigation system, which integrates multi-constellations GNSS precise point positioning (PPP), including GPS, GLONASS and Galileo, with low-cost micro-electro-mechanical sensor (MEMS) inertial system, for precise positioning applications. To integrate GNSS and the MEMS-based inertial system, the process and measurement models are developed. Tightly coupled mechanism is adopted, which is carried out in the GNSS raw measurements domain. Both un-differenced and between-satellite single-difference (BSSD) ionosphere-free linear combinations of pseudorange and carrier phase GNSS measurements are processed. Rigorous models are employed to correct GNSS errors and biases. The GNSS inter-system biases are considered as additional unknowns in the integrated error state vector. The developed stochastic model for inertial sensors errors and biases are defined based on first order Gaussian Markov process. Extended Kalman filter is developed to integrate GNSS and inertial measurements and estimate inertial measurements biases and errors. Two field experiments are executed, which represent different real-world scenarios in land-based navigation. The data are processed by using our developed Ryerson PPP GNSS/MEMS software. The results indicate that the proposed integrated system achieves decimeter to centimeter level positioning accuracy when the measurement updates from GNSS are available. During complete GNSS outages the developed integrated system continues to achieve decimeter level accuracy for up to 30 seconds while it achieves meter-level accuracy when a 60-second outage is introduced.

关键词： GNSS GPS Galileo GLONASS MEMS PPP Tightly Coupled

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The Use of Hinged Craniotomy in Comparison to Cisternostomy for Avoiding Bone Flap Replacement Second Surgery in Cases of Decompressive Craniotomy in Traumatic Brain Injury

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Open Journal of Modern Neurosurgery 2019年第1期9卷 7-16页

作者： ahmed El-Fiki Ehab abd-Haleem Department of Neurosurgery Cairo University Cairo Egypt

Introduction: Acute post traumatic subdural hematoma is a clinical condition with increased morbidity and mortality despite the developments in neurosurgery and urgent intervention is required to have best clinical outcome. We will evaluate hinged craniotomy technique in terms of offering adequate brain decompression plus avoiding removal of bone flap which requires second replacement surgery in comparison to cisternostomy effect. Material and Methods: A prospective study was conducted over 30 patients with traumatic acute subdural hematoma presented to neurotrauma unit in Cairo University hospitals from January 2017 to February 2018, operated by hinged craniotomy plus evacuation of hematoma and duroplasty. We avoid rapping the head with elastic bandage post-operative. Generous subcutaneous dissection (5 - 7 cm) all around skin flap was done routinely. Effect of brain decompression was evaluated by measuring the level of brain in relation to skull in post-operative computerized topography. Results: Twenty-one patients operated with initial GCS less than eight. Ten cases (33%) show that cortical surface in relation to skull bone was at inner table, nine cases (30%) at diploid layer and two cases (6.7%) at outer table in post-operative CT brain. Twenty patients died (66.7%);eight patients (26.6%) became fully conscious and two patients (6.7%) had vegetative outcome. No re-operation was done in any of our patients. Conclusion: Hinged craniotomy may be a safe and effective alternative technique with comparable results to cisternotomy in cases of traumatic brain injury that require decompression to avoid second surgery, especially in centres lacking cisternostomy experience. Although gaining cisternostomy experience may help in other indications, future prospective studies with larger number are required.

关键词： Decompression Subdural Hematoma Cisternostomy Traumatic Brain Injury

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PPP Accuracy Enhancement Using GPS/GLONASS Observations in Kinematic Mode

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Positioning 2015年第1期6卷 1-6页

作者： Mahmoud abd Rabbou ahmed El-Rabbany Department of Civil Engineering Ryerson University Toronto Canada

Commonly, kinematic PPP techniques employ un-differenced ionosphere-free linear combination of GPS observations. This, however, may not provide continuous solution in urban areas as a result of limited satellite visibility. In this paper, the traditional un-differenced as well as between-satellite single-difference (BSSD) ionosphere-free linear combinations of GPS and GLONASS measurements are developed. Except GLONASS satellite clock products, the final precise GPS and GLONASS satellites clock and orbital products obtained from the multi-GNSS experiment (MGEX) are used. The effects of ocean loading, earth tide, carrier-phase windup, sagnac, relativity, and satellite and receiver antenna phase-center variations are rigorously modeled. Extended Kalman filter (EKF) is developed to process the combined GPS/GLONASS measurements. A comparison is made between three kinematic PPP solutions, namely standalone GPS, standalone GLONASS, and combined GPS/ GLONASS solutions. In general, the results indicate that the addition of GLONASS observations improves the kinematic positioning accuracy in comparison with the standalone GPS PPP positioning accuracy. In addition, BSSD solution is found to be superior to that of the traditional un-diffe- renced model.

关键词： GPS GLONASS PPP Kalman Filter (KF)

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Web Quest and EFL Critical Reading and Writing

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Cultural and Religious Studies 2016年第3期4卷 175-184页

作者： Mervat abd Elfatah Ali Said ahmed Qassim University Qassim Saudi Arabia

This study aimed at investigating the effect of using a Web Quest program on developing some EFL critical reading and writing skills of the first year experimental secondary school students. The participants of the study were 60 students from one of the Experimental Secondary Schools in Egypt. Instruments of the study were EFL critical reading and writing tests. Students in both the experimental and the control groups were pre-tested using the critical reading test and the writing test. Then, students of the experimental group were using Web Quest. Finally, students in both groups were post-tested using the same instruments. The study showed that there was statistically significant difference between the mean scores of the pre and the post critical reading test and writing test of the experimental group in favor of the post tests. This difference can be attributed to using Web Quest.

关键词： Web Quest EFL critical reading and writing

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Some Notes on the Paper “New Common Fixed Point Theorems for Maps on Cone Metric Spaces”

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International Journal of Modern Nonlinear Theory and Application 2013年第2期2卷 150-151页

作者： Mohamed abd El-Rahman ahmed Department of Mathematics Faculty of Science Assiut University Assiut Egypt

In this paper, we show that Theorem 2.1 [1] (resp. Theorem 2.2 [1]) is a consequence of Corollary 2.1 [1] ( resp. Corollary 2.2 [1]).

关键词： Cone Metric Weakly Compatible Fixed Point

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Using Facebook to Develop Grammar Discussion and Writing Skills in English as a Foreign Language for University Students

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Sino-US English Teaching 2016年第12期13卷 932-952页

作者： Mervat abd Elfatah Ali Said ahmed Oklt Alsqoor College of Science and Arts Qassim University Qassim Saudi Arabia

This study aimed at investigating the effect of Facebook on grammar discussion and writing skill in English as a foreign language for university students, The study sample consisted of 60 students at Oklt AI Sqoor College of Science and Arts in Saudi Arabia and was divided into two groups： 30 students for the experimental group and 30 students for the control group. The instrument of the study was an EFL grammar and writing test. Students in both the experimental and the control group were pre-tested using the EFL （English as a Foreign Language） grammar and writing test, After that the experimental group was taught using Facebook while the control group was taught using the traditional method. Finally, students in both groups were post-tested using the EFL grammar and writing test. Results of the study showed that the experimental group outperformed the control group in the post-test of EFL grammar and writing. This difference can be attributed to using Facebook.

关键词： Facebook grammar discussion writing skill English as a foreign language

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A Note on the Paper “Generalized -Contraction for a Pair of Mappings on Cone Metric Spaces”

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Advances in Pure Mathematics 2012年第1期2卷 6-7页

作者： Mohamed abd El-Rahman ahmed 不详

We note that Theorem 2.3 [1] is a consequence of the same theorem for one map.

关键词： Generalized φ-Contraction Weakly Compatible Solid Cone

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Correlation between Mode of Delivery and Newborn’s Cord Blood Composition

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Open Journal of Obstetrics and Gynecology 2019年第3期9卷 395-403页

作者： abd El-Naser abd El-Gaber Ali ahmed Mustafa Mahmoud Obstetrics & Gynecology Department Qena Faculty of Medicine South Valley University Qena Egypt Medical Physiology Department Faculty of Medicine Sohag University Sohag Egypt

OBJECTIVE: The aim of this study is to find out the effect of delivery mode on newborn’s cord blood parameters particularly hemoglobin and hematocrite values. SETTING: Obstetrics and Gynecology Department, Qena Faculty of Medicine, South Valley University, Egypt. DURATION: From April 2015 to December 2017. STUDY DESIGN: A cross sectional study. METHODS: 900 live born neonates for healthy mothers were included in this study;all cases were delivered at full-term, with birth weight ranged from 2.5 to 3.5 Kg and had APGAR scores above 7 at 1 and 5 minutes. Newborns were divided into three groups (Group I included 300 newborns delivered by vaginal delivery without augmentation of labor, Group II included 300 newborns delivered vaginally with augmentation of labor and Group III included 300 newborns delivered by elective cesarean section). Blood sample was collected from the umbilical vein of each neonate for estimation of hemoglobin, hematocrit, RBCs count, platelets, WBCs count and reticulocytes. RESULTS: Cesarean section delivery had a statistically significant decrease in the level of iron-related hematologic indices including hemoglobin, hematocrit and RBCs count (p value 0.05). CONCLUSIONS: Cesarean section delivery had a significant decrease in the level of iron-related hematologic indices including hemoglobin, hematocrit and RBCs count and has a non-significant decrease in WBCs and platelets counts in neonatal cord blood, which suggest high prevalence of newborn iron-deficiency anemia among cesarean births particularly in developing communities.

关键词： Correlation Mode of Delivery Newborn Cord Blood Composition

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Cancellable Multi-Biometric Template Generation Based on Arnold Cat Map and Aliasing

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Computers, Materials & Continua 2022年第8期72卷 3687-3703页

作者： ahmed M.Ayoup Ashraf A.M.Khalaf Walid El-Shafai Fathi E.abd El-Samie Fahad Alraddady Salwa M.Serag Eldin Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMinia61111Egypt Electronics and Electrical Communications Engineering Department Faculty of Electronic EngineeringMenoufia University32952MenoufEgypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of EngineeringTanta UniversityTantaEgypt

The cancellable biometric transformations are designed to be computationally difficult to obtain the original biometric *** paper presents a cancellable multi-biometric identification scheme that includes four stages:biometric data collection and processing,Arnold’s Cat Map encryption,decimation process to reduce the size,and finalmerging of the four biometrics in a single generated ***,a 2D matrix of size 128×128 is created based on Arnold’s Cat Map(ACM).The purpose of this rearrangement is to break the correlation between pixels to hide the biometric patterns and merge these patterns together for more *** decimation is performed to keep the dimensions of the overall cancellable template similar to those of a single template to avoid data ***,some sort of aliasing occurs due to decimation,contributing to the intended distortion of biometric *** hybrid structure that comprises encryption,decimation,andmerging generates encrypted and distorted cancellable *** simulation results obtained for performance evaluation show that the system is safe,reliable,and feasible as it achieves high security in the presence of noise.

关键词： Aliasing technique selective encryption ACM decimation process

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