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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
open access

Low-cost solar array project. Task I. Silicon material. Investigation of the hydrogenation of SiCl/sub 4/

Description: Reaction kinetic measurements on the hydrochlorination of SiCl/sub 4/ and m.g. silicon metal were last reported as a function of reaction temperature, reactor pressure, H/sub 2//SiCl/sub 4/ ratio and silicon metal particle size distribution, 3 SiCl/sub 4/ + 2 H/sub 2/ + Si reversible 4 SiHCl/sub 3/. The effect of impurities in the m.g. silicon metal on the rate of this reaction has been investigated in this quarter. The m.g. silicon was replaced with high purity, electronic grade silicon metal … more
Date: October 7, 1980
Creator: Mui, J. Y. P. & Seyferth, D.
open access

Some Scoping Experiments for a Space Reactor

Description: Some scoping experiments were performed to evaluate fuel performance in a lithium heat pipe reactor operating at a nominal 1500K heat pipe temperature. Fuel-coolant and fuel-coolant-clad relationships showed that once a failed heat pipe occurs temperatures can rise high enough so that large concentrations of uranium can be transported by the vapor phase. Upon condensation this uranium would be capable of penetrating heat pipes adjacent to the failed pipe. The potential for propagation of failur… more
Date: July 7, 1983
Creator: Alexander, C. A. & Ogden, J. S.
open access

An MS-DOS-based program for analyzing plutonium gamma-ray spectra

Description: A plutonium gamma-ray analysis system that operates on MS-DOS-based computers has been developed for the International Atomic Energy Agency (IAEA) to perform in-field analysis of plutonium gamma-ray spectra for plutonium isotopics. The user interacts with the system by means of menus and screens that allow the user to select various applications and to enter information pertinent to a measurement. This information, along with the plutonium weight-percent-abundance results from the data analysis… more
Date: September 7, 1989
Creator: Ruhter, W. D. & Buckley, W. M.
open access

Hyper filter-fluorescer spectrometer for x rays above 120 keV

Description: An apparatus utilizing filter-fluorescer combinations is provided to measure short bursts of high fluence x-rays above 120 keV energy, where there are no practical absorption edges available for conventional filter-fluorescer techniques. The absorption edge of the prefilter is chosen to be less than that of the fluorescer, i.e., E/sub PRF/ < E/sub F/, contrary to the prior art technique E/sub PRF/ > E/sub F/. In this way, the response function is virtually zero between E/sub PRF/ and E/sub F/ a… more
Date: July 7, 1981
Creator: Wang, C. L.
open access

Design studies of a laser fusion power plant

Description: The conceptual design of a laser fusion power plant has been undertaken to exploit recent developments in target design. Advanced high-gain targets which have been developed make it possible to significantly relax the laser and optical system requirements. The power plant design features a reactor concept which utilizes a thick falling region of liquid lithium to protect the first-wall from the neutrons, x-rays, and charged particles that are produced in the thermonuclear microexplosion. The li… more
Date: October 7, 1977
Creator: Maniscalco, J. A.; Meier, W. R. & Monsler, M. J.
open access

Search for narrow states produced in the reaction. pi. /sup -/p. --&gt;. n +. gamma. &#x27;s at 13 GeV/c

Description: A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..--&gt;.. ..gamma gamma..n, ..pi../sup -/p ..--&gt;.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..--&gt;.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR &lt; 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma… more
Date: July 7, 1980
Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.
open access

Geotomography applied at the Stripa Mine in Sweden

Description: LLNL made ultrahigh-frequency (450-MHz) electromagnetic borehole-to-borehole transmissions in the Stripa Mine near Guldsmedshyttan, Sweden, in April 1979. Transmission loss measurements were made between four sets of 76-mm boreholes 30 m long, located at the end of a drift. Distances between the boreholes varied from 2 to 22 m. More than 25,000 data points were taken. A geotomograph was constructed to show the variation of attenuation between boreholes. The observed spatial variation of electro… more
Date: April 7, 1980
Creator: Okada, J.T.; Laine, E.F.; Lytle, R.J. & Daily,W.D.
open access

PWR Blowdown Heat Transfer Separate-Effects Program. Thermal-Hydraulic Test Facility experimental data report for test 103

Description: Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) test 103, which is part of the ORNL Pressurized-Water Reactor (PWR) Blowdown Heat Transfer Separate-Effects Program. The objective of the program is to investigate the thermal-hydraulic phenomenon governing the energy transfer and transport processes that occur during a loss-of-coolant accident in a PWR system.
Date: March 7, 1978
Creator: Clemons, V. D.; White, M. D.; Moore, P. A. & Hedrick, R. A.
open access

MTX (Microwave Tokamak Experiment) facility and machine grounding plan

Description: A key issue in the design of fusion research experiments and their related facilities is the control of ground currents. Because of the large magnetic field, high voltages and high currents present in most of these installations, it is essential to avoid ground loops, and to control ground currents during both normal operations and fault conditions. This paper describes the grounding policy that was developed for MTX. The vault area was divided into zones, and each of the four walls was treated… more
Date: October 7, 1987
Creator: Bell, H.H.; Rice, B.W.; Petersen, D.E. & Herrera, C.H.
open access

A miniature inexpensive, oxygen sensing element

Description: An exhaustive study was conducted to determine the feasibility of Nernst-type oxygen sensors based on ceramics containing Bi{sub 2}O{sub 3}. The basic sensor design consisted of a ceramic sensing module sealed into a metal tube. The module accommodated an internal heater and thermocouple. Thermal-expansion-matched metals, adhesives, and seals were researched and developed, consistent with sequential firings during sensor assembly. Significant effort was devoted to heater design/testing and to m… more
Date: October 7, 1991
Creator: Arenz, R. W.
open access

MFTF-B quasi-optical ECRH transmission system

Description: The microwave transmission system for ERCH on MFTF-B will utilize quasi-optical transmission techniques. The system consists of ten gyrotron oscillators: two gyrotrons at 28 GHz, two at 35 GHz, and six at 56 GHz. The 28 and 35 GHz gyrotrons both heat the electrons in the end plug (potential peak) while the 56 GHz sources heat the minimum-B anchor region (potential minimum). Microwaves are launched into a pair of cylindrical mirrors that form a pseudo-cavity which directs the microwaves through … more
Date: November 7, 1983
Creator: Yugo, J. J.; Shearer, J. W. & Ziolkowski, R. W.
open access

Acceleration using total internal reflection

Description: This report considers the use of a dielectric slab undergoing total internal reflection as an accelerating structure for charged particle beams. We examine the functional dependence of the electromagnetic fields above the surface of the dielectric for polarized incident waves. We present an experimental arrangement for testing the performance of the method, using apparatus under construction for the Grating Acceleration experiment at Brookhaven National Laboratory. 13 refs., 4 figs., 2 tabs.
Date: June 7, 1991
Creator: Fernow, R.C.
open access

Superconducting (radiation hardened) magnets for mirror fusion devices

Description: Superconducting magnets for mirror fusion have evolved considerably since the Baseball II magnet in 1970. Recently, the Mirror Fusion Test Facility (MFTF-B) yin-yang has been tested to a full field of 7.7 T with radial dimensions representative of a full scale reactor. Now the emphasis has turned to the manufacture of very high field solenoids (choke coils) that are placed between the tandem mirror central cell and the yin-yang anchor-plug set. For MFTF-B the choke coil field reaches 12 T, whil… more
Date: December 7, 1983
Creator: Henning, C. D.; Dalder, E. N. C.; Miller, J. R. & Perkins, J. R.
open access

Estimating and coping with public response to radioactive waste repository siting

Description: The siting and construction of a radioactive waste disposal operation is likely to be controversial in the communities being considered, and at the state and national levels as well. Public response can be conceptualized at two levels: individual, and group or organizational. At the individual level, public response is the behavior of people motivated by their attitudes, knowledge, and perceptions of radioactive waste and its hazards and risks. On the group or organizational level, public respo… more
Date: February 7, 1984
Creator: Payne, B.A.
open access

Evaluation of macroreticular anion exchange resin - RTA-893-R

Description: The macroreticular anion exchange resin, Amberlite IRA-900-OH, and an experimental resin from Ionac Chemical Company were irradiated by a /sup 60/Co source to doses of 5 x 10/sup 7/ rad and 10/sup 8/ rad. These doses approximate or exceed the dose encountered by the deionizer resins in 100-Area service. The loss in exchange capacity and the volume changes of Amberlite IRA-900 on irradiation were similar to those found previously for Amberlite IRA-400. The Ionac experimental resin, which had a c… more
Date: June 7, 1965
Creator: Baumann, E. W.
open access

Spatial averaging algorithms for ultrasonic inspection of austenitic stainless steel welds

Description: Interpretation of ultrasonic inspection data from stainless steel welds is difficult because the signal-to-noise ratio is very low. The three main reasons for this are the granular structure of the weld, the high attenuation of stainless steel, and electronic noise. Averaging in time at the same position in space reduces electronic noise, but does not reduce ultrasonic noise from grain boundary scattering. Averaging wave-forms from different spatial positions helps reduce grain noise, but desir… more
Date: April 7, 1980
Creator: Horn, J. E.; Cooper, C.S. & Michaels, T.E.
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