JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.10.6/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment-timezone/0.4.0/moment-timezone-with-data.js"></script>
<div id="result"></div>

JavaScript

var data = [
  [1442437200,1442470500],

  [1442473200,1442479500],

  [1442483100,1442489400],

  [1442493000,1442495700],

  [1442499300,1442505600],

  [1442508300,1442509200]
] 

var times = [];


for (var i=0;i<data.length;i++){
     for (var j=0;j<data[i].length;j++){
         var item = moment.tz(data[i][j]*1000, "Europe/Moscow").format(),
             itemTime = item.slice(item.indexOf('T')+1, item.indexOf('+')),
             timeFormat = itemTime.slice(0,5).split(':');

         var secondsHours = parseInt(timeFormat[0])*60*60,
             secondsMinutes = parseInt(timeFormat[1])*60,
             seconds = secondsHours + secondsMinutes;

         times.push(seconds)
     }
     var difference = times[1] - times[0];
     console.log('times__________' + times);
     times = [];
     console.log(difference);
 }