方法一，大部分模板可用

1、在latex 文档的开头导入cuted 宏包 \usepackage{cuted}

2、输入 

\begin{strip}

\rule{0.5\textwidth}{.4pt}%添加横线

\begin{equation}

a+b=c

\end{equation}

\hspace{0.5\textwidth}\rule{0.5\textwidth}{.4pt}%添加横线

\end{strip}

方法二，一部分模板可用

1、在latex 文档的开头导入widetext 宏包 \usepackage{widetext}

2、输入 

\begin{widetext}

\begin{equation}

a+b=c

\end{equation} 

\end{widetext}

3、此方法会自动添加横线。

4、一部分latex没有widetext 宏包，需要自行创建。

5、widetext 宏包创建方法，在latex编辑器新建文件，然后输入

\NeedsTeXFormat{LaTeX2e}

\ProvidesPackage{widetext}

%% Mimics the widetext environment of revtex4 for any other class package

%% Eg: article.cls

%%

%% Compiled by: Anjishnu Sarkar

%%

%% Advantages:

%% *) Supports float (eg: figure) in two column format (Advantage over

%%      multicol package)

%% *) One and twocolumn exist on the same page

%% *) Flow of text shown via rule

%% *) Equal height of text when in two column format

%%

%% Acknowledgment(s):

%% 1. Instead of re-inventing the wheel, two packages (flushend, cuted) of

%% the sttools bundle are used. The sttools bundle is available from CTAN.

%% Lisence of these packages rests with their corresponding author.

%% Any bug/problem with flushend and cuted should be forwarded to their

%% corresponding package authors.

%% 2. The idea of the rule came from the following latex community website

%% http://www.latex-community.org/forum/viewtopic.php?f=5&t=2770

%%

%% This package just defines the widetext environment and the rules.

%%

%% Usage:

%% \documentclass[a4paper,12pt,twocolumn]{article}

%% \usepackage{widetext}

%%

%% \begin{document}

%%

%% Some text in twocolumn

%%

%% \begin{widetext}

%% Text in onecolumn format.

%% \end{widetext}

%%

%% Some more text in twocolumn

%%

%% \end{document}

%%%%%%%%%%%%%%%%%%%%

%% Package required for equal height while in 2 columns format

\IfFileExists{flushend.sty}

{\RequirePackage{flushend}}

{\typeout{}

\typeout{Package widetext error: Install the flushend package which is

a part of sttools bundle. Available from CTAN.}

\typeout{}

\stop

}

%% Package required for onecolumn and twocolumn to exist on the same page.

%% and also required for widetext environment.

\IfFileExists{cuted.sty}

{\RequirePackage{cuted}}

{\typeout{}

\typeout{Package widetext error: Install the cuted package which is

a part of sttools bundle. Available from CTAN.}

\typeout{}

\stop

}

\newlength\@parindent

\setlength\@parindent{\parindent}

\if@twocolumn

\newenvironment{widetext}

{%

\begin{strip}

\rule{\dimexpr(0.5\textwidth-0.5\columnsep-0.4pt)}{0.4pt}%

\rule{0.4pt}{6pt}

\par %\vspace{6pt}

\parindent \@parindent

}%

{%

\par

\hfill\rule[-6pt]{0.4pt}{6.4pt}%

\rule{\dimexpr(0.5\textwidth-0.5\columnsep-1pt)}{0.4pt}

\end{strip}

}

\else

\newenvironment{widetext}{}{}

\fi

保存成 .sty文件，放在模板根目录下即可使用。