Temperature-Time Relations in Canned Foods During Sterilization

Bacteriologists have found that the death rate of the bacteria which cause spoilage in canned goods depends upon the temperature to which the bacteria are subjected. In order, therefore, to establish the bacteriology of canning on a firm scientific basis it is necessary to know the time at which certain critical temperatures are attained by the foods which are subjected to the sterilization process. This paper shows the result of an attempt to work out by a combination of mathematical theory and experiment the temperature-time curves for certain foods in containers of any size and for any practical temperature range

Effect of Air Pressure on the Vibration of Quartz Crystals

A quartz crystal which controls an oscillator is placed in a chamber which may be evacuated. The output of the oscillator increases as the air pressure is reduced

The Velocity of Ultra Waves in Ether Vapor

The velocity of high frequency sound waves has been determined in ether vapor at several pressures. The velocity is slightly less at the higher pressures

A Concave Ultrasonic Diffraction Grating

A new concave ultrasonic diffraction grating has been constructed and used in the measurement of wave-lengths between one and three millimeters. An oscillating quartz crystal is used as generator and receiver of the sound waves. Results are compared with those obtained by the Pierce interferometer and found to agree

Localization and Diagonalization: A review of functional integral techniques for low-dimensional gauge theories and topological field theories

We review localization techniques for functional integrals which have recently been used to perform calculations in and gain insight into the structure of certain topological field theories and low-dimensional gauge theories. These are the functional integral counterparts of the Mathai-Quillen formalism, the Duistermaat-Heckman theorem, and the Weyl integral formula respectively. In each case, we first introduce the necessary mathematical background (Euler classes of vector bundles, equivariant cohomology, topology of Lie groups), and describe the finite dimensional integration formulae. We then discuss some applications to path integrals and give an overview of the relevant literature. The applications we deal with include supersymmetric quantum mechanics, cohomological field theories, phase space path integrals, and two-dimensional Yang-Mills theory.Comment: 72 pages (60 A4 pages), LaTeX (to appear in the Journal of Mathematical Physics Special Issue on Functional Integration (May 1995)

Political and Policy Dimensions of Foreign Trade Zones: Expansion or the Beginning of the End?

Foreign Trade Zones ( zones ) have been touted as an essential element in expanding United States foreign commerce since their authorization in 1934. Over the last fifty years, structural changes have expanded the scope of the zone program, permitting the explosive growth of zone utilization. This expansion has caused renewed scrutiny of the entire zone program by the public and private sectors. Both United States industry and labor interests have objected to using zones for the manufacturing of products that subsequently are imported at substantial savings in customs duty. Further, opponents of the present zone program claim that the rapid increase in the number of zones and the manufacturing operations conducted therein have stolen jobs from more traditional domestic manufacturing operations. Proponents of zone expansion, including municipal and state authorities, argue that zone facilities attract industrial development to areas of the United States that otherwise might be outside of traditional international trade patterns. Proponents claim that zone operations have created a substantial number of jobs and have made domestic corporations more competitive

Relativistic Precessing Jets and Cosmological Gamma Ray Bursts

We discuss the possibility that gamma-ray bursts may result from cosmological relativistic blob emitting neutron star jets that precess past the line of sight. Beaming reduces the energy requirements, so that the jet emission can last longer than the observed burst duration. One precession mode maintains a short duration time scale, while a second keeps the beam from returning to the line of sight, consistent with the paucity of repeaters. The long life of these objects reduces the number required for production as compared to short lived jets. Blobs can account for the time structure of the bursts. Here we focus largely on kinematic and time scale considerations of beaming, precession, and blobs--issues which are reasonably independent of the acceleration and jet collimation mechanisms. We do suggest that large amplitude electro-magnetic waves could be a source of blob acceleration.Comment: 15 pages, plain TeX, accepted to ApJ

Velocity of Ultra-Sonic Waves in Vapor

The velocity of sound waves having a frequency of 107,500 cycles per second has been measured in water vapor and in ether vapor. The waves are generated by a quartz crystal oscillator and velocities measured by an interference method similar to that used by Pierce. The sound chamber is made air tight. After thorough exhaustion of the chamber with an air pump the vapor is introduced through a stop cock which connects the chamber with a glass bottle containing vapor. The sliding joint, through which the rod carrying the sound reflector passes, is made air tight by means of a rubber tube, which, by stretching and contracting, allows the reflector to be moved back and forth by a screw mounted outside the chamber