20 years after the discovery of the first planets outside our solar system,the current exoplanetary population includes more than 700 confirmed planets around m
The adsorption of cationic-nordonic mixed surfactant onto bentonite and its effect on bentonite structure were investigated.The objective was to improve the und
Background Pregnant women with heart disease are at high risk.Studies of risk factors of these patients are of great significance to improve maternal and fetal