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Health risks associated with heavy metals in the drinking water of Swat,northern Pakistan

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Journal of Environmental Sciences 2013年第10期25卷 2003-2013页

作者： Kifayatullah khan Yonglong Lu Hizbullah khan Shahida Zakir Ihsanullah Sardar khan Akbar Ali khan Luo Wei Tieyu Wang Department of Environmental Sciences University of Peshawar State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-environmental Sciences Chinese Academy of Sciences Nuclear Institute for Food and Agriculture

The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources （surface and groundwater） collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake （CDI） and health risk index （HRI） were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr 〉 Mn 〉 Ni 〉 Zn 〉 Cd 〉 Cu 〉 Pb and Cd 〉 Ni 〉 Mn 〉 Cr 〉 Cu 〉 Pb 〉 Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.

关键词： daily intake drinking water health risk heavy metals multivariate analysis

Non-Maximal Tripartite Entanglement Degradation of Dirac and Scalar Fields in Non-Inertial Frames

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Communications in Theoretical Physics 2014年第3期61卷 281-288页

作者： Salman khan Niaz Ali khan M.K.khan Department of Physics COMSATS Institute of Information Technology Chak Shahzad Department of Physics Quaid-i-Azam University

The π-tangle is used to study the behavior of entanglement of a nonmaximal tripartite state of both Dirac and scMar fields in accelerated frame. For Dirac fields, the degree of degradation with acceleration of both one-tangle of accelerated observer and π-tangle, for the same initial entanglement, is different by just interchanging the values of probability amplitudes. A fraction of both one-tangles and the π-tangle always survives for any choice of acceleration and the degree of initial entanglement. For scalar field, the one-tangle of accelerated observer depends on the choice of values of probability amplitudes and it vanishes in the range of infinite acceleration, whereas for 1r-tangle this is not always true. The dependence of π-tangle on probability amplitudes varies with acceleration. In the lower range of acceleration, its behavior changes by switching between the values of probability amplitudes and for larger values of acceleration this dependence on probability amplitudes vanishes. Interestingly, unlike bipartite entanglement, the degradation of π-tangle against acceleration in the case of sca/ar fields is slower than for Dirac fields.

关键词： tripartite entanglement noninertial frame

Systematic Geometric Error Modeling for Workspace Volumetric Calibration of a 5-axis Turbine Blade Grinding Machine

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Chinese Journal of Aeronautics 2010年第5期23卷 604-615页

作者： Abdul Wahid khan School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics

A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficiency grinding of turbine blades by eliminating the hand grinding process. Although its topology is RPPPR （P： prismatic; R： rotary）, its design is quite distinct from the competitive machine tools. As error quantification is the only way to investigate, maintain and improve its accuracy, calibra- tion is recommended for its performance assessment and acceptance testing. Systematic geometric error modeling technique is implemented and 52 position dependent and position independent errors are identified while considering the machine as five rigid bodies by eliminating the set-up errors of workpiece and cutting tool. 39 of them are found to have influential errors and are accommodated for finding the resultant effect between the cutting tool and the workpiece in workspace volume. Rigid body kinematics techniques and homogenous transformation matrices are used for error synthesis.

关键词： 5-axis machine tools calibration modeling geometric errors kinematics homogenous transformation matrices

MODELING DAM-BREAK FLOOD OVER NATURAL RIVERS USING DISCONTINUOUS GALERKIN METHOD

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Journal of Hydrodynamics 2012年第4期24卷 467-478页

作者： khan Abdul A. Glenn Department of Civil Engineering Clemson University

A well-balanced numerical model is presented for two-dimensional, depth-averaged, shallow water flows based on the Discontinuous Galerkin （DG） method. The model is applied to simulate dam-break flood in natural rivers with wet/dry bed and complex topography. To eliminate numerical imbalance, the pressure force and bed slope terms are combined in the shallow water flow equations. For partially wet/dry elements, a treatment of the source term that preserves the well-balanced property is presented. A treatment for modeling flow over initially dry bed is presented. Numerical results show that the time step used is related to the dry bed criterion. The intercell numerical flux in the DG method is computed by the Harten-Lax-van Contact （HLLC） approximate Riemann solver. A two-dimensional slope limiting procedure is employed to prevent spurious oscillation. The robustness and accuracy of the model are demonstrated through several test cases, including dam-break flow in a channel with three bumps, laboratory dam-break tests over a triangular bump and an L-shape bend, dam-break flood in the Paute River, and the Malpasset dam-break case. Numerical results show that the model is robust and accurate to simulate dam-break flood over natural rivers with complex geometry and wet/dry beds.

关键词： Discontinuous Galerkin (DG) method shallow water flows dam-break flood well-balanced scheme

SmokerViT: A Transformer-Based Method for Smoker Recognition

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Computers, Materials & Continua 2023年第10期77卷 403-424页

作者： Ali khan Somaiya khan Bilal Hassan Rizwan khan Zhonglong Zheng College of Mathematics and Computer Science Zhejiang Normal UniversityJinhua321004China School of Electronics Engineering Beijing University of Posts and TelecommunicationsBeijing100876China Department of Electrical Engineering and Computer Science Khalifa University of Science and TechnologyAbu Dhabi127788United Arab Emirates Key Laboratory of Intelligent Education of Zhejiang Province Zhejiang Normal UniversityJinhua321004China

Smoking has an economic and environmental impact on society due to the toxic substances it *** Neural Networks(CNNs)need help describing low-level features and can miss important ***,accurate smoker detection is vital with minimum false *** answer the issue,the researchers of this paper have turned to a self-attention mechanism inspired by the ViT,which has displayed state-of-the-art performance in the classification *** effectively enforce the smoking prohibition in non-smoking locations,this work presents a Vision Transformer-inspired model called SmokerViT for detecting ***,this research utilizes a locally curated dataset of 1120 images evenly distributed among the two classes(Smoking and NotSmoking).Further,this research performs augmentations on the smoker detection dataset to have many images with various representations to overcome the dataset size *** convolutional operations used in most existing works,the proposed SmokerViT model employs a self-attention mechanism in the Transformer block,making it suitable for the smoker classification ***,this work integrates the multi-layer perceptron head block in the SmokerViT model,which contains dense layers with rectified linear activation and linear kernel regularizer with L2 for the recognition *** work presents an exhaustive analysis to prove the efficiency of the proposed SmokerViT *** performance of the proposed SmokerViT performance is evaluated and compared with the existing methods,where it achieves an overall classification accuracy of 97.77%,with 98.21%recall and 97.35%precision,outperforming the state-of-the-art deep learning models,including convolutional neural networks(CNNs)and other vision transformer-based models.

关键词： Smoker recognition SmokerViT deep learning transformer for vision

Energy behavior of Boris algorithm

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Chinese Physics B 2021年第5期30卷 492-498页

作者： Abdullah Zafar Majid khan Department of Engineering and Applied Physics University of Science and Technology of ChinaHefei 230026China Department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan

Boris numerical scheme due to its long-time stability,accuracy and conservative properties has been widely applied in many studies of magnetized *** algorithms conserve the phase space volume and hence provide accurate charge particle ***,this algorithm does not conserve the energy in some special electromagnetic configurations,particularly for long simulation ***,we empirically analyze the energy behavior of Boris algorithm by applying it to a 2D autonomous *** energy behavior of the Boris method is found to be strongly related to the integrability of our Hamiltonian *** find that if the invariant tori is preserved under Boris discretization,the energy error can be bounded for an exponentially long time,otherwise the said error will show a linear *** the contrary,for a non-integrable Hamiltonian system,a random walk pattern has been observed in the energy error.

关键词： Boris algorithm invariant tori chaotic system Hénon-Heiles potential

The Fractional Investigation of Fornberg-Whitham Equation Using an Efficient Technique

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 259-273页

作者： Hassan khan Poom Kumam Asif Nawaz Qasim khan Shahbaz khan Department of Mathematics AbdulWali Khan UniversityMardan23200Pakistan Department of Mathematics Near East University TRNCMersin10Turkey Center of Excellence in Theoretical and Computational Science(TaCS-CoE)&KMUTTFixed Point Research Laboratory Room SCL 802 Fixed Point LaboratoryScience Laboratory BuildingDepartments of MathematicsFaculty of ScienceKing Mongkut’s University of Technology Thonburi(KMUTT)Bangkok10140Thailand Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40402Taiwan

In the last few decades,it has become increasingly clear that fractional calculus always plays a very significant role in various branches of applied *** this reason,fractional partial differential equations(FPDEs)are of more importance to model the different physical processes in nature more ***,the analytical or numerical solutions to these problems are taken into serious consideration and several techniques or algorithms have been developed for their *** the current work,the idea of fractional calculus has been used,and fractional FornbergWhithamequation(FFWE)is represented in its fractional view ***-knownmethod which is residual power series method(RPSM),is then implemented to solve *** are discussed through graphs and tables which conform to the higher accuracy of the proposed *** solutions at different fractional orders are obtained and shown to be convergent toward an integer-order *** the RPSM procedure is simple and straightforward,it can be extended to solve other FPDEs and their systems.

关键词： Caputo derivative fractional partial differential equations fornberg-whitham residual power series method

Heat Transfer Analysis for Dropwise-Filmwise Hybrid Surface of Steam on Vertical Plate

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Journal of Thermal Science 2021年第3期30卷 962-972页

作者： ALHASHEM Abdulwahab khan Jamil School of Technological Studies Public Authority for Applied Education and TrainingSafat 13092Kuwait Mechanical Engineering Department College of Engineering and ComputingUniversity of South CarolinaColumbiaSC 29201USA

A model is proposed to predict and evaluate the heat transfer characteristics of dropwise-filmwise hybrid *** is approached by modifying the original drop-size distribution,which is defined for fully dropwise condensation(DWC)and making it applicable for dropwise-filmwise condensation(DFC).The modification is achieved by simulation work to determine two parameters:the area fraction occupied by large drops f and the ratio of the maximum radius of newly formed drops to that of larger drops γ.Simulation results show a good agreement with the literature for fully DWC and provide a correlation for each parameter with respect to DWC region width in the DFC hybrid *** present model evaluates the heat transfer performance of DFC by utilizing these correlations.A comparison is made between the proposed model with experimental work from the literature and results show a good *** changing filmwise condensation(FWC)region width significantly affects the overall heat transfer performance,utilizing smaller width to that of DWC region has the advantage over fully ***,surface renewal within the hydrophobic region is controlled by adjusting the DWC region *** the ratio of drop maximum diameter to DWC region width is unity,surface renewal is achieved by drops merging to adjacent FWC regions *** the ratio is less than unity,surface renewal is achieved by sweeping of departing drops within the hydrophobic region and by *** each case,an optimum DWC region width which corresponds to the maximum DFC heat flux is defined.

关键词： dropwise-filmwise hybrid surface dropwise condensation region width filmwise condensation region width drop-size distribution maximum radius to region width ratio

Chemical composition and antioxidant activity of certain Morus species

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 973-980页

作者： Mohammad IMRAN Hamayun khan Mohibullah SHAH Rasool khan Faridullah khan Institute of Chemical Sciences University of Peshawar Department of Chemistry Islamia College University Pakistan Council of Scientific & Industrial Research (PCSIR) Laboratories Complex

In the present work,the fruits of four Morus species,namely Morus alba (white mulberry),Morus nigra (black mulberry),Morus laevigata (large white fruit),and Morus laevigata (large black fruit),were analyzed for proximate composition,essential minerals,and antioxidant *** this purpose,the ripe fruits were collected from the northern regions of *** major nutritional components moisture,ash,lipids,proteins,fibres,carbohydrates,and total sugar) were found to be in the suitable range along with good computed *** dry weight,pH,and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g,(3.20±0.07)–(4.78±0.15),and (0.84±0.40)%–(2.00±0.08)%,*** riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits,while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW).The mulberry fruits were rich with regard to the total phenol and alkaloid contents,having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW,*** quantities of essential macro-(K,Ca,Mg,and Na) and micro-(Fe,Zn,and Ni) elements were found in all the fruits.K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g,while Ca,Na,and Mg contents were (440±3.21)–(576±7.37),(260±3.86)–(280±3.50),and (240±3.51)–(360±4.20) mg/100 g,*** decreasing order of micro-minerals was Fe>Zn>*** radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective *** on the results obtained,mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.

关键词： Mulberry fruits Chemical composition 2 2-diphenyl-l-picrylhydrazyl (DPPH) radical scavenging activity Nutritional value. Pakistan