\documentclass[english,german]{scrartcl}
\usepackage[latin1]{inputenc}
\usepackage{geometry}
\geometry{verbose,a4paper,tmargin=1.75cm,bmargin=2cm,lmargin=2cm,rmargin=2cm,headheight=0.8cm,headsep=0.5cm,footskip=0.5cm}
\usepackage{babel}
\usepackage{url}
\urlstyle{same}
\newcommand\email{\begingroup \urlstyle{same}\Url}\usepackage{graphicx}
\usepackage{units}
\usepackage{tabularx}
\usepackage{wasysym} % enable use of \permil instead of \textperthousand
\usepackage{marvosym}
\usepackage{arabtex}
\usepackage{hyphenat}
\usepackage{booktabs}
\usepackage{mdwlist}
\renewcommand{\thefootnote}{\relax}
\usepackage{index}
\newindex{key}{kdx}{knd}{Keywords}
\newindex{author}{idx}{ind}{Authors}
\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\usepackage{ifpdf}
\ifpdf
%\usepackage[activate]{pdfcprot}
%\usepackage[owner=Tapioka, print=true, copy=true, edit=false, annotate=false,set]{pdfcrypt}
%encryption: not supported any more (since pdftex 1.10)
\usepackage[pdftex]{thumbpdf}
\usepackage[pdftex]{hyperref}
\hypersetup{pdftitle={Investigation and Comparison of Organic Pollution (polycyclic Aromatic Hydrocarbons (PAHs)) in Water of Gorganrod River and Talar River in Iran},pdfauthor={Leila Taheri Azad, Abbas Esmaili Sari, Kamran Rezai Tavabe},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Gorganrood and Talar Rivers, PAHs, pollution water},pdfpagemode=None,colorlinks=true}
\else
\usepackage{ae}
\usepackage{textcomp}
\fi
\begin{document}
\ifpdf
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2010.jpg}}}
\else
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2010.eps}}}
\fi
\hfill
\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 14-16, 2010, Zurich}}\\[1ex] \Large{``World Food System  ---\\A Contribution from Europe''\\[2ex]}}
\hspace{0.1cm}
\begin{center}
\Large{\textbf{Investigation and Comparison of Organic Pollution (polycyclic Aromatic Hydrocarbons (PAHs)) in Water of Gorganrod River and Talar River in Iran\footnote{\textbf{Contact Address:} Leila Taheri Azad, Tarbiyat Modares University, Department of Environmental Science, 3814894383~Arak, Iran, \mbox{e-mail}: \email{ltaheriazad@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Leila Taheri Azad$^{1}$, Abbas Esmaili Sari$^{2}$, Kamran Rezai Tavabe$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Tarbiyat Modares University, Department of Environmental Science, Iran}}}
\item[]{\small{\textit{$^{2}$Tarbiyat Modares University, Department of Environmental Science, Natural Recourses Faculty, }}}
\item[]{\small{\textit{$^{3}$University of Tehran, Department of Fishery, Iran}}}
\end{itemize*}
\index[author]{Taheri Azad, Leila}
\index[author]{Esmaili Sari, Abbas}
\index[author]{Rezai Tavabe, Kamran}
\begin{center}
\vspace{1.1cm}
\textbf{Abstract}
\begin{abstract}
\normalsize{
The Rivers are typical ecosystem and important source for drinking water.PAHs compounds are such as cancerous factors, mutation factors and environmental pollutant that mainly are produced from imperfect combustion of fossil fuel. To investigate and determination of PAHs contamination in surface water in the north of Iran Gorganrod River and Talar River has done assessment for ecological importance. In this study Water samples from input and discharge rivers were taken monthly during four season in 2006 year. In this survey after transferring samples to laboratory and processing, they were analysed by GC-1000 (Dany model). Determination and revelation were done with FID (flame ionisation detector). Extraction method in this survey was SPE (Solid"=phase extraction).The results of this study indicated that the maximum concentration of PAHs between input and discharge water was benzo \textbf{(a)}~pyrene compound in input water of Talar River (0/427 ppb) and 0/228 ppb of this compound in discharge water of Talar River and the maximum concentration of PAHs compounds in input water of Gorganrod river was naphthalene ( l/g$\mu$301/0)  and chrysene ( 0/\unitfrac[326]{l}{g}$\mu$) in discharge water in summer and the maximum level of these compounds  belong to benzo[k]fluoranthene in autumn (0/\unitfrac[509]{l}{g}$\mu$ and 0/\unitfrac[139]{l}{g}$\mu$ in input water and discharge water respectively). Also the result showed that indeno(1,2,3-c,d)pyrene, benzo(g,h,i)perylene, dibenzo[a,h]anthracene not detect in any water samples. On the other hand, during the season study the mean values of total PAHs in comparison with the US EPA permissible levels for fresh waters and drinking water were significantly less than the standards during this time zone but for separable PAHs such as benzo \textbf{(a)}~pyrene the mean values in comparison with the permissible levels for drinking water and fresh water were significantly high than the standards during this time zone in Talar river.}

\vspace{0.5cm}
\end{abstract}
\end{center}
\noindent \textbf{Keywords:} Gorganrood and Talar Rivers, PAHs, pollution water
\index[key]{Gorganrood and Talar Rivers}
\index[key]{PAHs}
\index[key]{Pollution water}
\end{document}