检索结果-南通市图书馆

Heavy Metal Levels and Ecological Risk in Crude Oil-Contaminated Soils from Okpare-Olomu, Niger Delta, Nigeria

Journal of Environmental Protection 2024年第4期15卷 415-438页

作者： Adedoyin Olubunmi Bankole Akinyemi Olufemi Ogunkeyede Harrison Agboro Prince Alex Ekhorutomwen Osasenaga Israel Otuomagie khadijah ateda isimekhai Ekaette Akpan Fadairo Efe Jeffery Isukuru Department of Environmental Management and Toxicology College of Science Federal University of Petroleum Resources Effurun Nigeria Department of Biology and Environmental Science College of Arts and Sciences University of New Haven West Haven USA Department of Chemistry University of Abuja Abuja Nigeria Department of Science Laboratory Technology Petroleum Training Institute Effurun Nigeria

Crude oil spills have inflicted extensive disruption upon the Niger Delta ecosystem, resulting in crop loss and severe environmental damage. Such spills exacerbate heavy metal concentration within soil due to the presence of metallic ions. The Okpare-Olomu community has borne the brunt of crude oil pollution from illicit bunkering, sabotage, and equipment malfunction. This study targets an evaluation of ecological hazards linked to heavy metals (HMs) in crude oil impacted agriculturally soils within Okpare-Olomu in Ughelli South LGA of Delta State. In this study, 24 topsoil samples were obtained from areas affected by crude oil pollution;the heavy metal content was evaluated through atomic absorption spectrometry. The concentration ranges for HMs (mg/kg) in soil were: 24.1 - 23,174 (Cu);0.54 - 37.1 (Cd);9.05 - 54 (Cr);12 - 174 (Ni);18.5 - 8611 (Pb);and 148 - 9078 (Zn) at a soil depth of 0 - 15 cm. Notably, metal concentrations were recorded to be above permissible World Health Organization limits. Predominantly, Zn and Pb recorded higher heavy metal concentration when compared to other heavy metals analysed, notably at sampling points PT7 through PT24. Zinc and Pb contamination exhibited highly significant contamination factors, and contamination severity was evidenced across all sample points, signifying a grave risk level. Pollution load indices indicated pervasive extreme pollution levels. Geoaccumulation indices signaled moderate to strong pollution, mainly by Pb and Zn. Ecological risk assessments revealed variable levels of heavy metal contamination, from low to very high, with potential ecological risk reflecting markedly elevated levels. This study underscores the imperative for soil remediation to rectify ecological imbalances in agriculturally affected soil constituents.

关键词： Heavy Metals Crude Oil Pollution Degree of Contamination Potential Risk Index

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On a Critical Fourth Order PDE with Navier Boundary Condition

引用

Acta Mathematica Sinica,English Series 2019年第12期35卷 1906-1916页

作者： khadijah SHARAF Department of Mathematics King Abdulaziz University

We consider a fourth order nonlinear PDE involving the critical Sobolev exponent on a bounded domain of R^n,n≥5 with Navier condition on the *** study the lack of compactness of the problem and we provide an existenc... 详细信息

关键词： Fourth order PDE critical nonlinearity variational problem critical points at infinity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Feature-Limited Prediction on the UCI Heart Disease Dataset

引用

Computers, Materials & Continua 2023年第3期74卷 5871-5883页

作者： khadijah Mohammad Alfadli Alaa Omran Almagrabi Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia

Heart diseases are the undisputed leading causes of death ***,the conventional approach of relying solely on the patient’s medical history is not enough to reliably diagnose heart *** potentially indicative factors exist,such as abnormal pulse rate,high blood pressure,diabetes,high cholesterol,*** analyzing these health signals’interactions is challenging and requires years of medical training and ***,this work aims to harness machine learning techniques that have proved helpful for data-driven applications in the rise of the artificial intelligence *** specifically,this paper builds a hybrid model as a tool for data mining algorithms like feature *** goal is to determine the most critical factors that play a role in discriminating patients with heart illnesses from healthy *** contribution in this field is to provide the patients with accurate and timely tentative results to help prevent further complications and heart attacks using minimum *** developed model achieves 84.24%accuracy,89.22%Recall,and 83.49%Precision using only a subset of the features.

关键词： Machine learning feature selection heart disease

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

TiC-Maraging stainless steel composite:microstructure, mechanical and wear properties

引用

Rare Metals 2006年第6期25卷 630-635页

作者： Akhtar Farid khadijah Ali Shah Syed Javid Askari School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Particulate TiC reinforced 17-4PH and 465 maraging stainless steel matrix composites were processed by conventional powder metallurgy （P/M）. TiC-maraging stainless steel composites with theoretical density 〉97% were produced using conventional P/M. The microstructure, and mechanical and wear properties of the composites were evaluated. The microstructure of the composites consisted of （core-rim structure） spherical and semi-spherical TiC particles depending on the wettability of the matrix with TiC particles. In TiC-maraging stainless steel composites, 465 stainless steel binder phase showed good wettability with TiC particles. Some microcracks appeared in the composites, indicating the presence of tensile stresses in the composites produced during sintering. The typical properties, hardness, and bend strength were reported for the composites. After heat treatment and aging, an increase in hardness was observed. The increase in hardness was at- tributed to the aging reaction in maraging stainless steel. The specific wear behavior of the composites strongly depends on the content of TiC particles and their interparticle spacing, and on the heat treatment of the maraging stainless steel.

关键词： TiC-maraging stainless steel composites aging wear powder metallurgy microcracks

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Physical aspects of magnetized Jeffrey nanomaterial flow with irreversibility analysis

引用

Chinese Physics B 2022年第8期31卷 485-493页

作者： Fazal Haq Muhammad Ijaz Khan Sami Ullah Khan khadijah M Abualnaja M A El-Shorbagy Department of Mathematics Karakoram International University Main CampusGilgit 15100Pakistan Department of Mathematics and Statistics Riphah International University I-14Islamabad 44000Pakistan Department of Mechanics and Engineering Science Peking UniversityBeijing 100871China Department of Mathematics COMSATS University IslamabadSahiwal 57000Pakistan Department of Mathematics and Statistics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Mathematics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj 11942Saudi Arabia Department of Basic Engineering Science Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt

This research presents the applications of entropy generation phenomenon in incompressible flow of Jeffrey nanofluid in the presence of distinct thermal features. The novel aspects of various features, such as Joule heating, porous medium,dissipation features, and radiative mechanism are addressed. In order to improve thermal transportation systems based on nanomaterials, convective boundary conditions are introduced. The thermal viscoelastic nanofluid model is expressed in terms of differential equations. The problem is presented via nonlinear differential equations for which analytical expressions are obtained by using the homotopy analysis method(HAM). The accuracy of solution is ensured. The effective outcomes of all physical parameters associated with the flow model are carefully examined and underlined through various curves. The observations summarized from current analysis reveal that the presence of a permeability parameter offers resistance to the flow. A monotonic decrement in local Nusselt number is noted with Hartmann number and Prandtl ***, entropy generation and Bejan number increases with radiation parameter and fluid parameter.

关键词： Jeffrey nonmaterial entropy generation magnetohydrodynamics(MHD) Bejan number porous medium Brownian motion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Temperature effect on the corrosion and passivation characterization of Ni_(82.3)Cr_7Fe_3Si_(4.5)B_(3.2) alloy in acidic media

引用

International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 205-214页

作者： khadijah M.Emran Sanaa T.Arab Aisha M.Al-Turkustani Hamad A.Al-Turaif Chemistry Department Faculty of Science Taibah University Department of Chemistry Faculty of Sciences Al-Faisaliah King Abdulaziz University Department of Chemical and Materials Engineering King Abdulaziz University

The effects of temperature on corrosion and the electrochemical behavior of Ni82.3Cr7Fe3Si4.5B3.2 glassy alloy in HC1,H2SO4,and H3PO4 acids were studied using AC and DC *** data reveal that the susceptibility to localized corrosion increases with increasing *** polarization curves reveal that the bulk glassy alloy is spontaneously passivated at all the investigated temperature in H2SO4 and H3PO4 solutions.A localized corrosion effect in HCl solution is clearly *** apparent activation energies in the regions of Tafel,active,and passive,as well as the enthalpies and entropies of the dissolution process were determined and *** high apparent activation energy（Ea） value for H3PO4 solution in Tafel region is explained by the low aggressivity of PO4^3- ions.

关键词： nickel alloys corrosion temperature effect acidic environment passivation polarization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Sialic Acid from Edible Bird Nest on Cell Viability Associated with Brain Cognitive Performance in Mice

引用

World Journal of Traditional Chinese Medicine 2019年第4期5卷 214-219页

作者： Siti khadijah Abdul Khalid Aswir Abd Rashed Saleha Abdul Aziz Hafandi Ahmad Departments of Veterinary Preclinical Sciences Faculty of Veterinary MedicineUniversiti Putra MalaysiaSerdangSelangor Departments of Veterinary Pathology and Microbiology Faculty of Veterinary MedicineUniversiti Putra MalaysiaSerdangSelangor Department of Nutrition Metabolic and Cardiovascular ResearchInstitute for Medical ResearchJalan PahangKuala LumpurMalaysia

Background:Edible bird nest(EBN)is a natural food product rich in glycoprotein such as sialic acid,which has been reported to improve brain *** EBN is widely consumed due to its higher nutritional contents and antioxidant status;however,an interaction of EBN on brain cell metabolic activity and viability are still ***:The objectives of this study were to identify the effect of sialic acid from EBN on the cell viability and to determine the appropriate concentration of sialic acid on cognitive performance in *** and Methods:The viability of pheochromocytoma and neuroblastoma cell lines were tested using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide *** in vivo study,7-week-old female BALB/c mice were randomly assigned into four treatment groups and were treated with sialic acid for 21 *** day 22,all mice were tested on cognitive performance by Y-maze ***:Treatment concentration of sialic acid extract and sialic acid standard at 60μg/mL(0.6 ppm)increased cell viability and showed no cytotoxicity effects in pheochromocytoma and neuroblastoma cell *** addition,an administration of higher dose of sialic acid at 0.6 ppm in animals improved Y-maze test performance,which they showed significantly higher number of entries and time spent in the novel ***:Thus,the current study shows that the sialic acid extract at 0.6 ppm improved brain cognitive performance in mice associated with an increased viability of pheochromocytoma and neuroblastoma cell lines.

关键词： Cell viability cognitive function edible bird nest mice sialic acid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Block Procedure with Linear Multi-Step Methods Using Legendre Polynomials for Solving ODEs

引用

Applied Mathematics 2015年第4期6卷 717-723页

作者： khadijah M. Abualnaja Department of Mathematics and Statistics College of Science Taif University Taif Saudi Arabia

In this article, we derive a block procedure for some K-step linear multi-step methods (for K = 1, 2 and 3), using Legendre polynomials as the basis functions. We give discrete methods used in block and implement it for solving the non-stiff initial value problems, being the continuous interpolant derived and collocated at grid and off-grid points. Numerical examples of ordinary differential equations (ODEs) are solved using the proposed methods to show the validity and the accuracy of the introduced algorithms. A comparison with fourth-order Runge-Kutta method is given. The ob-tained numerical results reveal that the proposed method is efficient.

关键词： Collocation Methods with Legendre Polynomials Initial Value Problems Perturbation Function Fourth-Order Runge-Kutta Method

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Predictive modeling of COVID-19 death cases in Pakistan

引用

Infectious Disease Modelling 2020年第1期5卷 897-904页

作者： Muhammad Daniyal Roseline Oluwaseun Ogundokun khadijah Abid Muhammad Danyal Khan Opeyemi Eyitayo Ogundokun Department of Statistics Islamia University of BahawalpurPakistan Department of Computer Science Landmark University Omu AranNigeria Research Evaluation Unit College of Physicians&SurgeonsPakistan Gillani Law College BZU MultanPakistan Directoriate Department Audit SectionAgricultural and Rural Management Training InstituteIlorinNigeria

Background:The world is presently facing the challenges posed by COVID-19(2019-nCoV),especially in the public health sector,and these challenges are dangerous to both health and *** disease results in an acute respiratory infection that may result in pain and *** Pakistan,the disease curve shows a vertical trend by almost 256K established cases of the diseases and 6035 documented death cases till August 5,***:The primary purpose of this study is to provide the statistical model to predict the trend of COVID-19 death cases in *** age and gender of COVID-19 victims were represented using a descriptive ***:ology:Three regression models,which include Linear,logarithmic,and quadratic,were employed in this study for the modelling of COVID-19 death cases in *** three models were compared based on R2,Adjusted R2,AIC,and BIC *** data utilized for the modelling was obtained from the National Institute of Health of Pakistan from February 26,2020 to August 5,***:The finding deduced after the prediction modelling is that the rate of mortality would decrease by the end of *** total number of deaths will reach its maximum point;then,it will gradually *** indicates that the curve of total deaths will continue to be flat,i.e.,it will shift to be constant,which is also the upper bound of the underlying function of absolute death.

关键词： Coronavirus COVID-19 Public health Epidemic Modelling Model selection criteria

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Explicit High-Order Method to Solve Coupled Nonlinear Schrödinger Equations

引用

Advances in Pure Mathematics 2021年第5期11卷 472-482页

作者： khadijah Alamoudi Mohmmad Said Hammoudeh Department of Math King Abdulaziz University Jeddah Saudi Arabia

Models of the coupled nonlinear Schrödinger equations submit various critical physical phenomena with a typical equation for optical fibres with linear refraction. In this article, we will presuppose the Compact Finite Difference method with Runge-Kutta of order 4 (explicit) method, which is sixth-order and fourth-order in space and time respectively, to solve coupled nonlinear Schrödinger equations. Many methods used to solve coupled nonlinear Schrödinger equations are second order in time and need to use extra-technique to rise up to fourth-order as Richardson Extrapolation technique. The scheme obtained is immediately fourth-order in one step. This approach is a conditionally stable method. The conserved quantities and the exact single soliton solution indicate the competence and accuracy of the article’s suggestion schemes. Furthermore, the article discusses the two solitons interaction dynamics.

关键词： Coupled Nonlinear Schrodinger Equations Sixth Order Method Interaction of Two Solitons Compact Finite Difference Runge-Kutta of Order 4 Method

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：