Instead of displaying each piece of the string in the loop, you could append it onto a variable that is displayed once at the end:
ciphertxt='nilesh';
disp(ciphertxt);
l=length(ciphertxt);
strOutput = '';
for i=1:l
t=ciphertxt(i);
n=abs(t);
b1=dec2bin(n,8);
strOutput = [strOutput ' ' b1];
% disp(b1);
end
disp(strOutput);
If you need different formatting of the string, use SPRINTF.
