\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{}



\author[1]{Yang He}%
\author[1]{Jin-Wei Liu}%
\author[1]{Si Chen}%
\author[2]{Si-Tong Liu}%
\author[1]{Hua-Zhang Zhao}%
\affil[1]{Peking University}%
\affil[2]{Qinghai University}%


\vspace{-1em}



  
  \date{May 27, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup








\sloppy


\par\null

\textbf{}

\textbf{}

\par\null



\textbf{Hosted file}

\verb`image1.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 1. Schematic illustration showing the structure, coagulation and
regeneration of MHC.

\textbf{Hosted file}

\verb`image2.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 2. Synthesis and structure of MHC.

\textbf{Hosted file}

\verb`image3.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 3. TEM images of MHC (a) and
Fe\textsubscript{3}O\textsubscript{4} (b), and FT-IR spectra (c) of MHC
and Fe\textsubscript{3}O\textsubscript{4}. Scale bars, 50 nm.

\textbf{Hosted file}

\verb`image4.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 4. Turbidity (a), UV\textsubscript{254} (b), TP (c) and
NO\textsubscript{3}\textsuperscript{-}-N (d) removal after the
coagulation of the secondary biological effluent using MHC and MSC as a
function of settling time with coagulant dosage of 0.8 mmol/L as total
Fe and PAM dosage in MSC is 0.4 mg/L.

\textbf{Hosted file}

\verb`image5.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 5. The relative abundance of CHO, CHON, CHOS, and CHONS in the
raw water and MHC coagulated water (a). Van Krevelen diagrams of CHON of
the raw water (b) and MHC coagulated water (c) with dosage of 0.8 mmol/L
as total Fe. Colored dots express the relative abundance. The black
lines in Van Krevelen diagrams divide CHON to seven major classes. The
bar diagram shows the relative abundance of seven classes of CHON in the
raw water and MHC coagulated water (d).

\textbf{Hosted file}

\verb`image6.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 6. Effect of initial NO\textsubscript{3}\textsuperscript{-}-N
concentration (a), pH (b), and ions (c) on the removal of
NO\textsubscript{3}\textsuperscript{-} and selectivity coefficient of
NO\textsubscript{3}\textsuperscript{-} to phosphate and sulfate (d). MHC
dose in c and d was 0.8 mmol/L as total Fe.

\textbf{Hosted file}

\verb`image7.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 7. Interaction energy between
NO\textsubscript{3}\textsuperscript{-} and N atom of quaternary ammonium
group at different relative positions (a). Nitrate positions during
removal categorized by total interaction potential (b). Van der Waals
and electrostatic interaction energy between nitrate and MHC (c). Number
of H bonds between NO\textsubscript{3}\textsuperscript{-} and
coordinating water molecules during removal process (d). Snapshots of
nitrate removal pathway by quaternary ammonium groups (e). O, red; N,
dark blue; H, gray; C, green. Methyl group C atoms on quaternary
ammonium N atoms in (a) were highlighted in light blue.

\textbf{Hosted file}

\verb`image8.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 8. Nitrate removal using MHC with and without magnetic field (a).
The MATLAB simulation of interaction potential energy between magnetic
particles under different magnetic field strengths (b). The parameters
used in the modeling process are in Table S3, and the raw water quality
is shown in Table S2.

\textbf{Hosted file}

\verb`image9.emf`  available at \url{https://authorea.com/users/339652/articles/465784-untitled-document}

Figure 9. MHC regeneration process schematic (a).
NO\textsubscript{3}\textsuperscript{-}-N concentration variations in the
desorption solution (b) and stripping solution (c) during regeneration.
Nitrate removal after repeated MHC regeneration (d).

\selectlanguage{english}
\FloatBarrier
\end{document}

