THE HYDROGEN-ION CONCENTRATION OF CERTAIN THREE SALT NUTRIENT SOLUTIONS FOR PLANTS

PERIODIC SOLUTIONS OF CERTAIN THREE DIMENSIONAL AUTONOMOUS SYSTEMS

There has been extensive work on the existence of periodic solutions for nonlinear second order autonomous differantial equations, but little work regarding the third order problems. The popular Poincare-Bendixon theorem applies well to the former but not the latter (see [2] and [3]). We give a necessary condition for the existence of periodic solutions for the third order autonomous system...

The effect of hydrogen ion concentration on the anatomy of tobacco

The Hydrogen-Ion Concentration of Cholera Stools

The Hydrogen-Ion Concentration of Human Fæces

Howe and Hawk (1912) were the first to determine the exact hydrogen-ion concentration of human fjeces. They examined samples of fa}ces from three individuals and found that the reaction of the material examined by them was always alkaline, varying with the different subjects and conditions from pH 7.01 to 8.77. Nelson and Williams (1916) recorded that 29 of the 30 individuals examined by them p...

The Optimum Hydrogen Ion Concentration for the Growth of Pneumococcus

1. The optimum hydrogen ion concentration for the growth of the various types of pneumococcus is a pH of about 7.8. 2. The limiting hydrogen ion concentrations for the growth of pneumococcus are a pH of 7.0 and a pH of 8.3. 3. Phosphates used in adjusting reactions of media retard growth if present in a concentration greater than 0.1 molecular. 4. Culture media for pneumococci should, therefore...