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H-M Bearing Capacity of A Modified suction Caisson Determined by Using Load-/Displacement-Controlled Methods

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China Ocean Engineering 2016年第6期30卷 926-941页

作者：张雨坤高玉峰李大勇 Ali H.mahfouz Key Laboratory of Ministry of Education for Geomechanies and Embankment Engineering Hohai UniversityNanjing 210098China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Faculty of Petroleum and Mining Engineering Suez UniversityIsmailiaEgypt

This paper presents a series of monotonically combined lateral loading tests to investigate the bearing capacity of the MsCs （modified suction caissons） in the saturated marine fine sand. The lateral loads were applied under load- and displacement-controlled methods at the loading eccentricity ratios of 1.5, 2.0 and 2.5. Results show that, in the displacement-controlled test, the deflection-softening behavior of load-deflection curves for MsCs was observed, and the softening degree of the load-deflection response increased with the increasing external skirt length or the decreasing loading eccentricity. It was also found that the rotation center of the MsC at failure determined by the load-controlled method is slightly lower than that by the displacement-controlled method. The calculated MsC capacity based on the rotation center position in serviceability limit state is relatively conservative, compared with the calculated capacity based on the rotation center position in the ultimate limit state. In the limit state, the passive earth pressures opposite the loading direction under load- and displacement-controlled methods decrease by 46% and 74% corresponding to peak values, respectively; however, the passive earth pressures in the loading direction at failure only decrease by approximately 3% and 7%, compared with their peak values.

关键词： MsC (modified suction caisson) saturated marine fine sand model tests load- and displacement-controlled loading laterally combined bearing capacity earth pressure

Convenient One Pot synthesis and Antibacterial Evaluation of some New Mannich Bases Carrying 1,2,4-Triazolyl Moiety

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Chinese Journal of Chemistry 2011年第8期29卷 1661-1668页

作者： Arafa, Wael A. A mohamed, Asmaa s Department of Chemistry Faculty of Science Fayoum University Fayoum Egypt Department of Medical Chemistry Theodor Bilharz Research Institute Egypt

A series of Mannich bases were synthesized by a three-component Mannich reaction. The newly synthesized compounds were well characterized by elemental analyses, IR, NMR and mass spectroscopic studies. The potential antibacterial effects of the synthesized compounds were investigated using standard bacterial strains： Gram-positive and Gram-negative bacteria. Interestingly, all the synthesized compounds were observed to be promising leads, possessing moderate to significant inhibitory activity as compared to standard.

关键词： bi- 1,2,4-triazoles schiff bases Mannich bases regioselectivity antibacterial activity

Development of new potentiometric sensors for the determination of proguanil hydrochloride in serum and urine

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Chinese Chemical Letters 2016年第6期27卷 857-863页

作者： Fatehy M.Abdel-Haleem mohamed saad mohamed s.Rizk Chemistry Department Faculty of Science Cairo University

Potentiometric electrodes were developed for the rapid determination of proguanil hydrochloride in pure samples, pharmaceutical preparations and spiked serum and urine samples using PVC membrane,screen printed（sPE）, coated wired（CWE）, carbon paste（CPE） and modified carbon paste（MCPE）electrodes based on the ion-exchanger of proguanil with phosphotungestic acid（Pr-PT） as a chemical modifier. The prepared electrodes showed Nernestian slopes of 59.7, 58.1, 58.5, 58.5 and 57.0 for the PVC,sPE, CWE, CPE and MCPE for the proguanil ions in a wide concentration range of 1.0 ＊ 10^-5–1.0 ＊ 10^-2mol L^-1 at 25°C with detection limits of 7.94 ＊ 10^-6, 1.0 ＊ 10^-5, 1.0 ＊ 10^-6, 7.07 ＊ 10^-6 and 2.5 ＊ 10^-6 mol L^-1, respectively. The prepared electrodes exhibited high proguanil selectivity in relation to several inorganic ions and sugars and they could be successfully utilized for its determination in pure solutions, pharmaceutical preparations and serum and urine samples using the direct potentiometry and standard addition methods with very good recovery values.

关键词： Proguanil hydrochloride PVC membrane electrode Carbon paste electrode screen printed electrode MWCNTs Coated wire electrode

A significant improvement in adsorption behavior of mesoporous TUD-1 silica through neodymium incorporation

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Journal of Rare Earths 2021年第4期39卷 469-476页

作者： Badria M.Al-shehri sahar K.mohamed shaykha Alzahly mohamed s.Hamdy Catalysis Research Group(CRG) Department of ChemistryCollage of ScienceKing Khalid UniversityP.O.Box 2009Abha61413Saudi Arabia Chemistry Department Collage of ScienceUmm Al-Qura UniversityMakkah21421Saudi Arabia Chemistry Department Faculty of ScienceHelwan UniversityAin HelwanCairo11795Egypt King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh11451Saudi Arabia

Neodymium was incorporated into the three-dimensional mesoporous siliceous material *** order to understand the chemical and morphological structure of the prepared material,several characterization techniques were *** characterization results show the formation of highly distributed isolated Nd3+ions incorporated in the silica matrix in tetrahedrally coordinated structure,moreover no aggregation of separate phase(s)was/were *** prepared material was investigated as an adsorbent for methyl green(MG)dye in aqueous solution as a model cationic *** results show higher adsorption capacity for Nd-TUD-1 by almost 24 times higher than the neat parent TUD-1 material and more than 100 times higher than bulky Nd_(2)O_(3)under neutral *** adsorption results were fitted perfectly with pseudo-second-order ***,the adsorption isotherms were perfectly fitted with Freundlich isotherm model which indicates the formation of a multilayer of the dye molecules onto the Nd-TUD-1 surface as a physisorption with endothermic nature.

关键词： Adsorption Neodymium TUD-1 Mesoporous silica Water treatment Kinetics

Networked Control Approach for Distributed Generation systems

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IEEE/CAA Journal of Automatica sinica 2018年第4期5卷 836-851页

作者： Magdi s.Mahmoud mohamed saif Ur Rahman systems Engineering Department King Fahd University of Petroleum and MineralsP.O.Box 5067Dhahran 31261Saudi Arabia

Microgrid has emerged as an answer to growing demand for distributed generation(DG) in power systems. It contains several DG units including microalternator, photovoltaic system and wind generation. It turns out that sustained operation relies on the stability of these constituent systems. In this paper, a microgrid consisting of microalternator and photovoltaic system is modeled as a networked control system of systems(so s)subjected to packet dropouts and delays. Next, an observerbased controller is designed to stabilize the system in presence of the aforementioned communication constraints and simulation results are provided to support the control design methodology.

关键词： Microalternator microgrid systems networked control observer-based controller photovoltaic systems

Hot Forging of Nitrogen Alloyed Duplex stainless steels

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Journal of Materials science & Technology 2007年第1期23卷 111-117页

作者： P. Chandramohan s.s.mohamed Nazirudeen s. s.Ramakrishnan Department of Mechatronics Eng Sri Krishna College of Eng and TechCoimbatore 641008India Dept. of Metallurgy PSG College of TechnologyCoimbatore 641004India Mechanical Eng VLB Janakiammal college of Eng and TechCoimbatore 641004India

Duplex stainless steels are gaining global importance because of the need for a high strength corrosion resistant material. Three compositions of this group were selected with three different nitrogen contents ciz, 0.15 wt pct （alloy 1）, 0.23 wt pct （alloy 2） and 0.32 wt pct （alloy 3）. The steels were melted in a high frequency induction furnace and hot forged to various reductions from 16% to 62%. In this work, the effect of hot forging on the ferrite ***, hardness, yield strength, impact strength and grain orientation （texture） were studied. Fracture analysis on all the forged specimens using sEM reveals that a size reduction of 48% results in maximum ductility and impact strength as well as minimal ferrite content and grain size. Thus the mechanical properties are found to have a direct correlation to ferrite content and grain size. The highest impact strength was observed in specimens with the smallest grain size, which was observed in specimens forged to 48% reduction in size.

关键词： Duplex Austenite Ferrite Forging solutionizing

Paleoecology of Benthic Foraminifera in Coral Reefs Recorded in the Jurassic Tuwaiq Mountain Formation of the Khashm Al-Qaddiyah Area, Central saudi Arabia

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Journal of Earth science 2015年第2期26卷 224-235页

作者： mohamed Youssef Abdelbaset s.El-sorogy Department of Geology and Geophysics College of Science King Saud University Department of Geology Faculty of Science South Valley University Department of Geology Faculty of Science Zagazig University

Thirty three benthic foraminiferal species belong to 23 genera and 16 families have been recorded from the coral reefs of the Callovian Tuwaiq Formation, Khashm AI-Qaddiyah area, Central saudi Arabia. Three species： Astacolus qaddiyahensis, Nodosaria riyadhensis, siderolites jurassica are believed to be new. Nearly all identified foraminifera are of Atlantie-Miditeranean affinity. The foraminiferal assemblage recorded in the present work is mixed of open marine, moderately deep marine conditions associations and shallow to deep lagoon. The reefal part of upper Twiaq Formation may have been deposited in shallow water of lower to middle shelf depth （20-50 m） as indicated by abundant corals and benthic foraminifera. The coral fauna and bearing benthic foraminifera indicated moderate water energy.

关键词： coral reef benthic foraminifera Jurassic Tuwaiq Formation saudi Arabia.

Men’s Perception of Domestic Violence, Rural Minia, Egypt

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Open Journal of Preventive Medicine 2016年第2期6卷 106-114页

作者： Ebtesam Esmail Hassan Amany Edward seedhom Eman mohamed mahfouz Public Health Department Faculty of Medicine Minia University Minia Egypt

Background: Domestic violence is an important prevalent, yet hidden and ignored health concern with significant impact on women’s health and wellbeing. This research was guided by the belief that men could play a role in preventing domestic violence as the majority of domestic violence is perpetrated by men. Aim: To assess attitudes of men towards domestic violence and factors affecting violence supportive attitude. Methods: A cross-sectional community-based study conducted in a rural area, Minia District, 2015. A systematic random sample was used. An interview-administered questionnaire was used including questions related to violence supportive environments, and opinion of men of causes and existence of domestic violence within families. Gender equity score (GEs) was applied. Results: A total of 440 males participated. 57.3% of the participants reported that domestic violence was sometimes justified and needed in certain cases, and nearly two third (69%) of them practiced violence against their wives mostly in the form of physical one (64%). small proportion of males reported high support for gender equity (7%). The study identified reasons for domestic violence, as perceived by men: The commonest was marital disputes (48.9%), followed by financial problems (36.4%) and social and economic disparity between the spouses (12.7%). Regarding the effect of violence on families, 30.9% of males reported that it led to lack of proper education. Conclusion and Recommendations: There is a tendency to describe this community as abusive. There is a need for development of relevant and culturally sensitive domestic violence education/prevention program in rural Egypt.

关键词： Domestic Violence Male Perception Rural Minia Egypt

Digital Watermarking scheme for securing Textual Database Using Histogram shifting Model

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Computers, Materials & Continua 2022年第6期71卷 5253-5270页

作者： Khalid A.El Drandaly Walid Khedr Islam s.mohamed Ayman mohamed Mostafa Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt College of Computer and Information sciences Jouf UniversitySakaka72314Saudi Arabia

Information security is one of the most important methods of protecting the confidentiality and privacy of internet *** greater the volume of data,the more the need to increase the security methods for protecting data from *** task can be challenging for researchers in terms of managing enormous data and maintaining their safety and *** of digital content is a major issue in maintaining the privacy and secrecy of *** this end,digital watermarking is based on the concept of information security through the insertion and detection of an embedded watermark in an efficient *** methodologies in the research on digital watermarking result in data distortion after embedding the *** scenario can reduce the efficiency of detecting watermarks as well as violate data *** study adapts a robust reversible histogram shifting(Hs)technique for textual data in relational ***,the study presents a digital watermarking scheme intended for document copyright protection and proof of *** major advantage of the proposed watermarking scheme is that it can protect digital data and preserve data *** the best of our knowledge,this research methodology is promising for use in the Hs expansion model for watermarking data on nonnumeric *** addition,the results showed that despite exposing the database to an insertion attacks at 50%and 75%of the watermark,the proposed algorithm can recovermore than half of the embedded watermark in all addition and alteration attacks *** a result,the watermark information can be retained and restored completely.

关键词： Information security digital watermarking information hiding histogram shifting technique