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Evaluation of sediment contamination in the Red Sea coastal area combining multiple pollution indices and multivariate statistical techniques

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International Journal of Sediment Research 2021年第2期36卷 243-254页

作者： Yousef saeed Saleh Biology Department Faculty of Science Taiz University

In the recent years, the Red Sea coast of Yemen has been severely affected by intensive anthropogenic activities. The current study constitutes a thorough inquiry to evaluate the extent of heavy metals pollution in Yemen’s Red Sea coast sediment and identifies the possible sources of pollution. The concentrations of five metals(copper(Cu), zinc(Zn), cadmium(Cd), lead(Pb), and nickel(Ni)) collected from nine sites along the Red Sea coast of Yemen were assessed using an atomic absorption spectrophotometer(ASS). Sediment quality indices, such as the sediment quality guidelines(SQGs), potential ecological risk(RI), contamination factor(CF), pollution load index(PLI), geoaccumulation index(Igeo), and modified degree of contamination(m Cd) were computed. In addition, multivariate statistical techniques(principal component analysis(PCA),hierarchical cluster analysis, and Pearson’s correlation analysis) were applied to identify the potential sources of metals. The mean concentrations of Cu, Zn, Cd, Pb, and Ni were 51.3, 61.9, 4.02, 9.9, and 33.4 mg/kg dry wt, respectively. The spatial distribution revealed that the metals concentrations were high at the middle zone and low southward of Hodeida city. According to the SQGs, the adverse biological effects of metals were occasionally associated with Cu and Cd, frequently associated with Ni, and not expected to occur with Zn and Pb. The RI indicated that the sediment of the studied sites pose low(RI mean effect range-median quotient(m-ERm-Q) indicated that the combination of the studied metals had the toxicity probability of 21% at all studied sites. Igeo and CF indicated that the metals concentrations were in the descending order of: Zn > Ni > Pb > Cd > Cu,whereas the PLI and m Cd indicated that Ras Isa(Site 5) and Urj village(Site 6) were the most polluted ***, cluster analysis, and correlation analysis found that Cd, Pb, and Ni mostly originated from anthropogenic

关键词： Red Sea Heavy metals Pollution Spatial distribution Sediment quality

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粒用高粱的产量因素分析

国外农学-杂粮作物 1987年第3期 33-37页

作者： m.saeed 傅景昌

由于产量因素拥用多重特性,并且气候对它们的表达也随时产生影响,因此高粱籽粒的产量形成是很复杂的。虽然产量的其它因素也能通过粒数和籽粒大小两个主要因素来影响产量,但籽粒的最终产量主要由这两个主要产量因素来决定。Eastin 等（1... 详细信息

由于产量因素拥用多重特性,并且气候对它们的表达也随时产生影响,因此高粱籽粒的产量形成是很复杂的。虽然产量的其它因素也能通过粒数和籽粒大小两个主要因素来影响产量,但籽粒的最终产量主要由这两个主要产量因素来决定。Eastin 等（1974）曾指出与高粱产量有关的三个关键生长阶段,即 GS1(播

关键词：产量高粱杂交种粒重籽粒大小

Study of Thermal Reactivity and Kinetics of HmX and Its PBX by Different methods

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火炸药学报 2017年第2期40卷 24-32页

作者： mohamed Abd-Elghany Thomas m.Klapotke Ahmed Elbeih saeed Hassanein Tamer Elshenawy Department Chemie Ludwig-Maximilians Universitat Munchen 81377 Munchen Germany military Technical College Kobry Elkobbah Cairo Egypt Technical Research Center Cairo Egypt

Vacuum Stability Test(VST)was used to determine the thermal behavior and kinetic parameters of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HmX)and its mixture with hydroxyl-terminated polybutadiene(HTPB)as a binder coded as HmX/*** fitting and isoconversional method were applied to determine the kinetic parameters based on VST *** comparison,non-isothermal thermogravimetry analysis data(TGA)was also used to calculate the kinetic parameters by using Kissinger,OFW(Ozawa,Flynn,and Wall)and KAS(Kissinger-Akahira-Sunose)*** Kinetics and Technology Solution(AKTS)software was also used to determine the decomposition kinetics of the studied *** Scanning Calorimetry(DSC)was employed to determine the decomposition heat flow properties of the studied *** show that the activation energies obtained using VST results is 360.1kJ/mol for pure HmX and 186.9kJ/mol for HmX/*** activation energies obtained by the three different methods using TGA results are in the range of 360-368kJ/mol for pure HmX and 190-206kJ/mol for HmX/*** is concluded that values of kinetic parameters obtained by VST are close to that obtained by the different techniques using TG/DTG *** onset decomposition peak of HmX/HTPB is lower than that of HmX where the HTPB binder has negative effect on the thermal stability of *** results of all the applied techniques prove that HmX/HTPB has lower activation energy and heat release than the pure *** polymeric matrix has negative effect on the kinetic parameters of HmX.

关键词： HmX HmX/HTPB 火炸药质量管理研究工作 PBX

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An autoregressive integrated moving average model for short-term prediction of hepatitis C virus seropositivity among male volunteer blood donors in Karachi,Pakistan

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World Journal of Gastroenterology 2009年第13期15卷 1607-1612页

作者： saeed Akhtar Shafquat Rozi Department of Community medicine and Behavioral Sciences Faculty of MedicineKuwait University Department of Community Health Sciences Medical CollegeAga Khan University

AIm： To identify the stochastic autoregressive integrated moving average （ARImA） model for short term forecasting of hepatitis C virus （HCV） seropositivity among volunteer blood donors in Karachi, Pakistan.mETHODS： Ninety-six months （1998-2005） data on HCV seropositive cases （1000-1 x month1） among male volunteer blood donors tested at four major blood banks in Karachi, Pakistan were subjected to ARImA modeling. Subsequently, a fitted ARImA model was used to forecast HCV seropositive donors for 91-96 mo to contrast with observed series of the same months. To assess the forecast accuracy, the mean absolute error rate （%） between the observed and predicted HCV seroprevalence was calculated. Finally, a fitted ARImA model was used for short-term forecasts beyond the observed series.RESULTS： The goodness-of-fit test of the optimum ARImA （2,1,7） model showed non-significant autocorrelations in the residuals of the model. The forecasts by ARImA for 91-96 mo closely followed the pattern of observed series for the same months, with mean monthly absolute forecast errors （%） over 6 mo of 6.5%. The short-term forecasts beyond the observed series adequately captured the pattern in the data and showed increasing tendency of HCV seropositivity with a mean ± SD HCV seroprevalence （1000^-1× month^-1） of 24.3 ±1.4 over the forecast interval.CONCLUSION： To curtail HCV spread, public health authorities need to educate communities and health care providers about HCV transmission routes based on known HCV epidemiology in Pakistan and its neighboring countries. Future research may focus on factors associated with hyperendemic levels of HCV infection.

关键词： Hepatitis C virus Blood donor Ecologicalanalysis Autoregressive integrated moving averagemodel Pakistan

Effects of magnetic Field on Entropy Generation in Flow and Heat Transfer due to a Radially Stretching Surface

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Chinese Physics Letters 2013年第2期30卷 155-159页

作者： Adnan saeed Butt Asif Ali Department of mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan

We investigate the effects of magnetic field on the entropy generation during fluid flow and heat transfer due to the radially stretching *** partial differential equations governing the flow and heat transfer phenomenon are transformed into nonlinear ordinary differential equations by using suitable similarity *** equations are then solved by the homotopy analysis method and the shooting *** effects of the magnetic field parameter m and the Prandtl number Pr on velocity and the temperature profiles are ***,influence of the magnetic field parameter m and the group parameter Br/Ω on the local entropy generation number Ns as well as the Bejan number Be are *** is observed that the magnetic field is a strong source of entropy production in the considered problem.

关键词： technique. surface. entropy

Effect of chemical activation process on adsorption of As(V) ion from aqueous solution by mechano-thermally synthesized zinc ferrite nanopowder

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International Journal of minerals,metallurgy and materials 2020年第4期27卷 526-537页

作者： mohammad Sefidmooy Azar Shahram Raygan saeed Sheibani School of metallurgy and materials Engineering College of EngineeringUniversity of TehranTehranIran

Nanostructured ZnFe2O4 was synthesized by the heat treatment of a mechanically activated mixture of ZnO/α-Fe2O3.X-ray diffraction(XRD)and differential thermal analysis(DTA)results demonstrated that,after 5 h of the mechanical activation of the mixture,ZnFe2O4 was formed by heat treatment at 750°C for 2 *** improve the characteristics of ZnFe2O4 for adsorption applications,the chemical activation process was *** 2 h chemical activation with 1 mol·L?1 HNO3 and co-precipitation of 52%?57%dissolved ZnFe2O4 led to an increase in the saturated magnetization from 2.0 to 7.5 emu·g?1 and in the specific surface area from 5 to 198 m2·g?*** addition,the observed particle size reduction of chemically activated ZnFe2O4 in field emission scanning electron microscopy(FESEm)micrographs was in agreement with the specific surface area *** improvements in ZnFe2O4 characteristics considerably affected the adsorption performance of this *** results revealed that mechano-thermally synthesized ZnFe2O4 had the maximum arsenic adsorption of 38%with the adsorption capacity of 0.995 mg·g?1 in a 130 mg·L?1 solution of As(V)after 30 min of ***,chemically activated ZnFe2O4 showed the maximum arsenic adsorption of approximately 99%with the adsorption capacity of 21.460 mg·g?1 under the same *** results showed that the weak adsorption performance of mechano-thermally synthesized ZnFe2O4 was improved by the chemical activation process.

关键词： zinc ferrite mechano-thermal chemical activation adsorption arsenic(V)

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A comparison of elderly (20～65 yrs) life style with body mass index (BmI)25 附视频

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海南医学院学报 2010年第3期16卷 311-314页

作者： m.saeed Heydarnejad Ali Hassanpour Dehkordi Department of Biology Faculty of Sciences Faculty of medical Sciences Shahrekord University

Objective:compare the habits and features of obese (BmI>25) and normal (BmI25 kg/m2 were assigned to the case (obsess) group and those with BmI ranging from 20 to 25 were assigned to control (normal) *** miller-Smith ... 详细信息

Objective:compare the habits and features of obese (BmI>25) and normal (BmImethod to ameliorate the life styles using a cross-sectional ***:A total of 220 randomly selected cases were divided into case group (n=110) and control group (n=100) according to the calculated BmI *** with BmI>25 kg/m2 were assigned to the case (obsess) group and those with BmI ranging from 20 to 25 were assigned to control (normal) *** miller-Smith life style questionnaires consisting 20 questions each with 5 different answers were given to both *** of the questionnaires were collected and analyzed using t-test and Chi-square with ***:No significant differences were found among the two groups in terms of the mean age,gender,level of education,marital status,insurance,breakfast,lunch or dinner,fried meat,legumes,caffeinated beverages,the length of sleep during 24 h,cigarette smoking and losing job or ***,in regards to use of vegetables,sausage,fried potatoes,enriched breads,low fat milk,low salt,candies and chocolates significant relations were found (Pmeliorate the life *** is a relation between health and stress and irregularity of meals,such as breakfast skipping,is associated with overweight and obesity in adolescence.

关键词： Life style Obsess Body mass index (BmI)

Three-dimensional oscillation of an acoustic microbubble between two rigid curved plates

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Journal of Hydrodynamics 2021年第5期33卷 1019-1034页

作者： Kawa m.A.manmi Imad A.Aziz Arun Arjunan Rostam K.saeed Abdolrahman Dadvand Department ofmathematics College of ScienceSalahaddin University-ErbilKurdistan RegionIraq Department of Information Technology College of Engineering and Computer ScienceLebanese French UniversityKurdistan RegionIraq Faculty of Science and Engineering University of WolverhamptonWolverhamptonUK Faculty of mechanical Engineering Urmia University of TechnologyUrmiaIran Karlsruhe Institute of Technology(KIT) Institute for Chemical Technology and Polymer ChemistryKarlsruheGermany

Understanding the near boundary acoustic oscillation of microbubbles is critical for the effective design of ultrasonic biomedical devices and surface cleaning ***,this study investigates the three-dimensional microbubble oscillation between two curved rigid plates experiencing a planar acoustic field using boundary integral method(BIm).The numerical model is validated via comparison with the nonlinear oscillation of the bubble governed by the modified Rayleigh-Plesset equation and with the axisymmetric model for an acoustic microbubble in infinite fluid ***,the influence of the wave direction and horizontal standoff distance(h)on the bubble dynamics(including jet velocity,jet direction,centroid movement,total energy,and Kelvin impulse)were *** was concluded that the jet velocity,the maximum radius and the total energy of the bubble are not significantly influenced by the wave direction,while the jet direction and the high-pressure region depend strongly on *** importantly,it was found that the jet velocity and the high-pressure region around the jet in acoustic bubble are drastically larger than their counterparts in the gas bubble.

关键词： Acoustic microbubble bubble dynamics boundary integral method(BIm) two curved plates potential flow

URL Phishing Detection Using Particle Swarm Optimization and Data mining

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Computers, materials & Continua 2022年第12期73卷 5625-5640页

作者： saeed m.Alshahrani Nayyar Ahmed Khan Jameel Almalki Waleed Al Shehri College of Computing and IT-Shaqra University Shaqra155572Saudi Arabia Department of Computer Science College of Computer in Al-LeithUmm Al-Qura UniversityMakkahSaudi Arabia

The continuous destruction and frauds prevailing due to phishing URLs make it an indispensable area for *** techniques are adopted in the detection process,including neural networks,machine learning,or hybrid techniques.A novel detection model is proposed that uses data mining with the Particle Swarm Optimization technique(PSO)to increase and empower the method of detecting phishing *** selection based on various techniques to identify the phishing candidates from the URL is *** this approach,the features mined from the URL are extracted using data mining *** features are selected on the basis of URL *** classification of these features identified by the data mining rules is done using PSO *** selection of features with PSO optimization makes it possible to identify phishing *** a large number of rule identifiers,the true positive rate for the identification of phishing URLs is maximized in this *** experiments show that feature selection using data mining and particle swarm optimization helps tremendously identify the phishing URLs based on the structure of the URL ***,it can minimize processing time for identifying the phishing website ***,the approach can be beneficial to identify suchURLs over the existing contemporary detecting models proposed before.

关键词： Phishing particle swarm optimization feature selection data mining classification cloud application