Method and apparatus for producing concentric hollow spheres

Hollow spheres with precisely concentric inner and outer spherical surfaces are formed by applying vibrations to a nonconcentric hollow sphere while it is at an elevated temperature at which it is fluid or plastic, the vibrations producing internal flows which cause the inner and outer surfaces to become precisely concentric. Concentric spheres can be mass produced by extruding a material such as glass or metal while injecting a stream of gas into the center of the extrusion to form a gas-filled tube. Vibrations are applied to the extruded tube to help break it up into individual bodies of a desired uniform size, the bodies tending to form spherical inner and outer surfaces by reason of surface tension, and the continuing application of vibrations causing these surfaces to become concentric

Acoustic energy shaping

A suspended mass is shaped by melting all or a selected portion of the mass and applying acoustic energy in varying amounts to different portions of the mass. In one technique for forming an optical waveguide slug, a mass of oval section is suspended and only a portion along the middle of the cross-section is heated to a largely fluid consistency. Acoustic energy is applied to opposite edges of the oval mass to press the unheated opposite edge portions together so as to form bulges at the middle of the mass. In another technique for forming a ribbon of silicon for constructing solar cells, a cylindrical thread of silicon is drawn from a molten mass of silicon, and acoustic energy is applied to opposite sides of the molten thread to flatten it into a ribbon

Normal modes of a compound drop

The modes are characterized by their frequency, the attendant displacement of fluid boundaries, and the flow pressure fields within the fluids. The drops consist of three fluids; a core fluid, a fluid shell surrounding the core, and a host fluid surrounding the shell. These fluids are assumed to be inviscid and incompressible, and the core and the shell to be concentric. The theory is obtained by linearization of the equations of fluid motion to the lowest order of nonlinearity that yields the normal modes. Numerical values of mode frequencies and the associated relative displacements of the fluid boundaries are presented for several specific systems, and the results compared with observations

Analyses of the Nmr Spectra of the Vinyl Protons of Cyclopentadiene and Cyclohexadiene Using Spin Decoupling

Nuclear magnetic resonance spectra of vinyl protons of cyclopentadiene and cyclohexadiene from spin decouplin

Acoustic bubble removal method

A method is described for removing bubbles from a liquid bath such as a bath of molten glass to be used for optical elements. Larger bubbles are first removed by applying acoustic energy resonant to a bath dimension to drive the larger bubbles toward a pressure well where the bubbles can coalesce and then be more easily removed. Thereafter, submillimeter bubbles are removed by applying acoustic energy of frequencies resonant to the small bubbles to oscillate them and thereby stir liquid immediately about the bubbles to facilitate their breakup and absorption into the liquid

Noncontact temperature pattern measuring device

Laser pyrometer techniques are utilized to accurately image a true temperature distribution on a given target without touching the target and without knowing the localized emissivity of the target. The pyrometer utilizes a very high definition laser beam and photodetector, both having a very narrow focus. The pyrometer is mounted in a mechanism designed to permit the pyrometer to be aimed and focused at precise localized points on the target surface. The pyrometer is swept over the surface area to be imaged, temperature measurements being taken at each point of focus

At Cross Purposes: U.S.-Taiwan Relations since 1942,

For years, “one China” has meant two completely different Chinas masquerading as one country—the People’s Republic of China (PRC) and Taiwan (a.k.a. the Republic of China [ROC]). The PRC is huge, with a population of 1.3 billion, while Taiwan has only twenty-two million people in comparison. There are other differences as well: Taiwan is rich, with a per capita income in 2003 of over $23,000, versus the PRC’s per capita$5,000; Taiwan’s 5 percent unemployment rate is half, its 1 percent poverty rate is a tenth, and its seventy-seven-year life expectancy is five years more than those of the PRC. More importantly, during the past de- cade Taiwan adopted a multiparty democracy, while the PRC has only one legal political party that is holding tightly onto its autocratic powers—the Chinese Communist Party

Review Essay

At the end of the Cold War, the Soviet navy was eliminated almost overnight as the world’s second most powerful naval force. Russia’s Pacific fleet is now so poorly supplied and equipped that it rarely leaves port. This unprecedented reversal of fortune has created a maritime vacuum throughout East Asia, leaving a wide range of regional powers, including the People’s Republic of China (PRC), Taiwan, the Republic of Korea, and Japan, hoping to fill that vacuum

The Geopolitics of East Asia: The Search for Equilibrium, by Robyn LimChinese Grand Strategy and Maritime Power

One of the most intriguing questions about the People’s Republic of China (PRC) today is whether its communist government does or does not have the “ambition” to acquire a blue-water navy. If building an oceangoing fleet is among Beijing’s long-term goals, then China may one day become a dan- gerous peer competitor of the United States. If so, a future Sino-U.S. mari- time conflict is possible; if not, Wash- ington’s primarily maritime power and Beijing’s primarily continental power need never meet in battle