This research studied the methods and techniques that can be applied to measure the surface finish of a cylindrical part during the grinding process. The applicability, capability, and feasibility of the techniques and roughness measurement methods are the main research objectives. Through a literature survey and various technique investigations, it was established that an ultrasonic technique has the greatest promise.
In unhairing operations, the tanner desires a dis-solution of the epidermis with a minimum breakdown of hair and corium tissues. Comparatively little is known about the chemical structure of epidermis, due to practical difficulties in obtaining relatively complete, unmodified, uncontaminated samples of this tissue. Epidermis for this work was obtained from three animals by two methods calculated to yield a minimum of modification. These methods were (1) removal at less than 10°C with dilute sodium chloride solutions, with precautions taken against bacterial action, and (2) removal by the action of distilled water at 60°C. for a period of ten minutes.
One of the important steps in the making of leather is the process known as bating or puering. This operation consists in treating the limed, unhaired skins with materials containing a proteolytic enzyme absorbed on an inert material, plus a deliming salt such as ammonium sulfate. The object of the process is to reduce some of the alkalinity of the skin and remove, from the grain surface particularly, any substance which would interfere with subsequent tanning operations.
Two of the properties of skin collagen which are of fundamental interest to the biochemist, and of practical concern the tanner, are the water-holding power of the protein, and the shrinkage temperature phenomenon. It was felt that the most worthwhile results could best be obtained by employing the most modern instrumental methods. In consequence a large part of the work was devoted to the development of electronic instrumentation, to aid in obtaining the desired information. The versatile high frequency oscillator titrimeter was adapted for the dielectric constant work on the water relationships of collagen, and an electrical strain gauge, and associated high-gain electronic amplifier, was developed to study the force shrinkage behavior of the collagen.
Metaplastic charges due to vitamin A-deficiency and overstimulation with estrogen were studied in the uterus of the rat. The investigation was concerned with the following problems: (1) the role of the ovaries in producing uterine metaplasia in vitamin A-deficient rats; (2) whether uterine metaplasia which is induced by estrogen is a gradual process or a rapid one, which takes place a short time after the beginning of treatment; (3) whether the age of the animal at the start of estrogen treatment has any effect on the production of metaplasia; and (4) a cytologic comparison of the metaplastic processes resulting from vitamin A-deficiency with those resulting from overstimulation with estrogen.