List of Articles Kjeldahl method Open Access Article Abstract Page Full-Text 1 - Comparative study on the effect of natural rubber protein content obtained by two Kjeldahl and Fourier transform infrared spectroscopy (FTIR) methods on the tensile properties of natural rubber based compound Masoomeh Sadeghi Mercedeh Malekzadeh saeed taghvaei Fereshteh Motiee 10.30495/jacr.2022.1948413.2006