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Preconcentration and Determination of Trace Amounts of Heavy Metals in Water Samples Using Membrane Disk and Flame Atomic Absorption Spectrometry

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Chinese Journal of Chemistry 2007年第5期25卷 640-644页

作者： ali, Moghimi Department of Chemistry Varamin Campus Islamic Azad University Varamin Iran

A fast and simple method for preconcentration of Ni^2＋, Cd^2＋, Pb^2＋, Zn^2＋, Cu^2＋ and Co^2＋ from natural water samples was developed. The metal ions were complexed with sodium diethyldithiocarbamate （Na-DDTC）, then adsorbed onto octadecyl silica membrane disk, recovered and determined by FAAS. Extraction efficiency, influence of sample volume and eluent flow rates, effects of pH, amount of Na-DDTC, nature and amount of eluent for elution of metal ions from membrane disk, break through volume and limit of detection have been evaluated. The effect of foreign ions on the percent recovery of heavy metal ions has also been studied. The limit of detection of the proposed method for Ni^2＋, Cd^2＋, Pb^2＋, Zn^2＋, Cu^2＋ and Co^2＋was found to be 2.03, 0.47, 3.13, 0.44, 1.24 and 2.05 ng·mL^-1, respectively. The proposed （DDTC） method has been successfully applied to the recovery and determination of heavy metal ions in different water samples.

关键词： preconcentration atomic absorption spectrometry solid phase extraction octadecyl bonded silica

Stability analysis of Markovian jumping stochastic Cohen Grossberg neural networks with discrete and distributed time varying delays

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Chinese Physics B 2014年第6期23卷 131-137页

作者： M.Syed ali Department of Mathematics Thiruvalluvar University

In this paper, the global asymptotic stability problem of Markovian jumping stochastic Cohen-Grossberg neural networks with discrete and distributed time-varying delays （MJSCGNNs） is considered. A novel LMI-based stability criterion is obtained by constructing a new Lyapunov functional to guarantee the asymptotic stability of MJSCGNNs. Our results can be easily verified and they are also less restrictive than previously known criteria and can be applied to Cohen-Grossberg neural networks, recurrent neural networks, and cellular neural networks. Finally, the proposed stability conditions are demonstrated with numerical examples.

关键词： Cohen-Grossberg neural networks global asymptotic stability linear matrix inequality Lyapunovfunctional time-varying delays

Computer-aided Prediction of the ZrO_2 Nanoparticles' Effects on Tensile Strength and Percentage of Water Absorption of Concrete Specimens

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Journal of Materials Science & Technology 2012年第1期28卷 83-96页

作者： ali Nazari Shadi Riahi Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing ZrO2 nanoparticles have been developed at different ages of curing. For building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models were arranged in a format of eight input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models, the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles. It has been found that neural network （NN） and gene expression programming （GEP） models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network have predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

关键词： Concrete Curing medium Zr02 nanoparticles Artificial neural network Geneticprogramming Split tensile strength Percentage of water absorption

Extraordinary adsorption of acidic fuchsine and malachite green onto cheap nano-adsorbent derived from eggshell

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1591-1602页

作者： Atefeh Moosavi ali Akbar Amooey ali alinejad mir Mojtaba Hedayati Marzbali Faculty of Chemistry University of MazandaranBabolsarIran Department of Chemical Engineering University of MazandaranBabolsarIran Chemical&Environmental Engineering School of EngineeringRMIT UniversityMelbourneVictoria 3000Australia

Removal of dyestuffs such as Acidic Fuchsine(AF)and Malachite Green(MG)being present in many forms in industries is vital to protect water reservoirs from their catastrophic effects on the *** study attempts to effectively eliminate these dyes using a low-cost and eco-friendly ***,as a biocompatible by-product,was initially characterized,then some modifications were conducted,and its morphology and chemical structure were then examined through(Atomic force microscopy)AFM,(Fourier-Transform Infrared Spectroscopy)FTIR,(Energy-Dispersive X-ray Spectroscopy)EDS and(Brunauer–Emmett–Teller)BET *** revealed that the modifications on raw material gave rise to a natural nano-adsorbent presenting porous medium appropriate for targeted adsorbate molecules with the average particle size and average pore diameter of 54 and^2 nm,*** groups on the adsorbent surface were also of importance to assist the adsorption of AF and *** effect of contact time,adsorbent dose,solution p H and initial concentration was ***-second order model accurately correlated the experimental kinetic data for both ***,the participation of intra-particle diffusion along with film diffusion in controlling the process was *** isotherm model fitted very well to the equilibrium data for both dyes and maximum monolayer adsorption capacity of AF and MG was accordingly calculated to be 5000 and 3333.33 mg·g-1 *** inherent characteristics of eggshell make it a potential material to remove contaminants from wastewater in future applications.

关键词： Egg shell Acidic Fuchsine Malachite Green Ultrahigh adsorption

Binding energy produced within the framework of the accretion of millisecond pulsars

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Chinese Physics C 2023年第4期47卷 11-15页

作者： ali Taani Physics Department Faculty of ScienceAl Balqa Applied University19117 SaltJordan

The role and implication of binding energy through the accretion-induced collapse(AIC)of accreting white dwarfs(WDs)for the production of millisecond pulsars(MSPs)are *** binding energy model is examined due to the dynamic process in closed binary systems,and the possible mass of the companion sufficient to induce their orbital parameters is *** deterministic nature of this interaction has a strong sensitivity to the equation of state of the binary systems(where the compactness of a neutron star is proportional to the amount of binding energy)associated with their initial *** behavior mimics the commonly assumed mass and amount of accreted matter under the instantaneous mass loss(ΔM~0.18M_(⊙)).As a result,this indicates an increase in the MSP’s gravitational mass due to angular momentum *** outcome of such a system is then a circular binary MSP in which the companion is a low-mass WD,thus distinguishing the binary formation *** addition,the results of this work could provide constraints on the expected mass and binding energy of a neutron star based on the accretion rate.

关键词： binding energy pulsars evolution kinematics and dynamics

Towards a coherent nomenclature of plant viruses

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Virologica Sinica 2016年第3期31卷 197-198页

作者： Muhammad ali Atta-ur-Rahman School of Applied Biosciences (ASAB) National University of Sciences and Technology(NUST)

The International Committee on Taxonomy of Viruses（ICTV）has the decree to set the rules for the classification and naming of *** species is the lowest level considered in the taxonomic *** general,virus species are ... 详细信息

关键词： Genus coherent isolation taxonomic mosaic instance letter names abbreviated mottle

Minimizing the Discrepancy Between Source and Target Domains by Learning Adapting Components

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Journal of Computer Science & Technology 2014年第1期29卷 105-115页

作者： Fatemeh Dorri ali Ghodsi Department of Computer Science University of British Columbia Department of Statistics and Actuarial Science University of Waterloo

Predicting the response variables of the target dataset is one of the main problems in machine learning. Predictive models are desired to perform satisfactorily in a broad range of target domains. However, that may not be plausible if there is a mismatch between the source and target domain distributions. The goal of domain adaptation algorithms is to solve this issue and deploy a model across different target domains. We propose a method based on kernel distribution embedding and Hilbert-Schmidt independence criterion （HSIC） to address this problem. The proposed method embeds both source and target data into a new feature space with two properties： 1） the distributions of the source and the target datasets are as close as possible in the new feature space, and 2） the important structural information of the data is preserved. The embedded data can be in lower dimensional space while preserving the aforementioned properties and therefore the method can be considered as a dimensionality reduction method as well. Our proposed method has a closed-form solution and the experimental results show that it works well in practice.

关键词： domain adaptation kernel embedding Hilbert-Schmidt independence criterion

Robustness of Genuine Tripartite Entanglement under Collective Dephasing

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Chinese Physics Letters 2015年第6期32卷 6-9页

作者： MAZHAR ali Department of Electrical Engineering Faculty of EngineeringIslamic University in Madinah

We study the robustness of genuine multipartite entanglement for a system of three qubits under collective dephasing. Using a computable entanglement monotone for multipartite systems, we find that almost every state is quite robust under this type of decoherence. We analyze random states and weighted graph states at infinity and find all of them to be genuinely entangled.

关键词： Robustness of Genuine Tripartite Entanglement under Collective Dephasing

A Simple Human Vulnerability Index to Climate Change Hazards for Pakistan

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International Journal of Disaster Risk Science 2012年第3期3卷 163-176页

作者： Fazal ali Khan ali Salman Social Science and Economics Department Shaheed Zulfikar Ali Bhutto Institute of Science and Technology(SZABIST)Islamabad 44000Pakistan Rural Support Programmes Network(RSPN) Islamabad 44000Pakistan Development Pool Islamabad 44000Pakistan

This article explores the spatial pattern of vulnerability to climate change hazards in Pakistan by developing a Human Vulnerability Index(HVI). For this purpose, we use Population Census 1998 and Agriculture Census 2000 data. The HVI places the 103 districts of Pakistan in rank order and looks at whether there is a correlation between human vulnerability and exposure to disaster of the districts with respect to climate change hazards such as floods. The HVI is further validated using an independent flood recovery data set. The study found that the HVI is a useful tool for identifying vulnerable regions and districts for resource allocation. But the HVI is a poor tool for vulnerability assessment at community and household levels. For this purpose we used logistic regression analysis, which indicates that the adult literacy rate, ownership of livestock, and access to electricity are the three(out of six) key variables that play a critical positive role in recovery after the 2010 floods. The primary data collected from households also reveal that the 2010 Pakistan floods have equally affecte d standing crops, livestock, and house structures. More than two-thirds of sample households had rebuilt their house structures, whereas livestock recovery was negligible since the floods. We also found that the 2010 floods affected some of the poverty regions of the country, but that there is a very weak systematic correlation between human vulnerability and disaster exposure.

关键词： floods disaster district