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in subjects: "X Radiation"

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Effects of Ionizing Radiation on Seeds of Barley

For some time we have been interested in the influence of radiation with different specific ionizations on the relation of the production of genetic changes to survival and seedling injury in irradiated seeds of barley. Our studies have shown that barley seeds subjected to any given dose of thermal neutrons or fast neutrons are much more uniformly affected than seeds treated with any given dose of x-rays or 2 Mev electrons. In addition, it has been demonstrated that when dormant seeds of barley… more

Date: unknown

Creator: Caldecott, Richard, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The Effect of Certain Gases on the Radiosensitivity of Habrobracon During Development

Groups of Habrobracon during postembryonic development were exposed to X-rays in the presence of oxygen, carbon dioxide, nitrogen and hydrogen. The effects on development to adulthood were observed. Pupae exposed to 100 per cent oxygen (without X-radiation) were arrested in their development. Diploid female pupae were more resistant to X-rays and more sensitive to oxygen than were comparable haploid male pupae. Groups of Habrobracon irradiated during the larva-in-cocoon stage in the presence of… more

Date: unknown

Creator: Clark, A. M. & Herr, E. B., Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Secondary Tetanus Antitoxin Responses in Mice Elicited Prior to Irradiation

The pioneer study by Benjamin and Sluka in 1908 on inhibition of antibody formation by X-rays revealed the importance of the temporal relationship between exposure to radiation and injection of antigen. X-radiation delivered three days before injection of beef serum inhibited precipitin formation in rabbits. A similar exposure to X-rays delivered three days after injection of the antigen failed to repress production of specific antibody. These observations were partially confirmed in 1915 when … more

Date: March 6, 1963

Creator: Hale, William M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Hanford Special X-Ray Photometer: Mark II

The special x-ray photometer was designed to measure various characteristics of high-absorption materials by comparing the attenuation of an x- ray beam in passing through a sample of known size with the attenuation through a standard. A general description, discussion of elements, safety features and cautions alignment and adjustment, and operation and maintenance are presented.

Date: unknown

Creator: Cartmell, T. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Calculation of Control Rod Worth in APPR-1

7 rods were used in the APPR-1 rather than 5. The critical experiments and calculations from the use of the rods, including the capability of any four to shut down the cold reactor are examined in this study.

Date: unknown

Creator: Giesler, H. W. & Gallagher, J. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Soft x-ray camera for internal shape and current density measurements on a noncircular tokamak

Soft x-ray measurements of the internal plasma flux surface shaped in principle allow a determination of the plasma current density distribution, and provide a necessary monitor of the degree of internal elongation of tokamak plasmas with a noncircular cross section. A two-dimensional, tangentially viewing, soft x-ray pinhole camera has been fabricated to provide internal shape measurements on the PBX-M tokamak. It consists of a scintillator at the focal plane of a foil-filtered pinhole camera,… more

Date: May 1, 1988

Creator: Fonck, R. J.; Jaehnig, K. P.; Powell, E. T.; Reusch, M.; Roney, P. & Simon, M. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Summary of radiation-induced transient absorption and recovery in fiber optic waveguides. [Pulsed electrons and x-rays]

The absorption induced in fiber optic waveguides by pulsed electron and X-ray radiation has been measured as a function of optical wavelength from 450 to 950 nm, irradiation temperature from -54 to 71/sup 0/C, and dose from 1 to 500 krads. The fibers studied are Ge-doped silica core fibers (Corning Low Loss), ''pure'' vitreous silica core fibers (Schott, Bell Laboratories, Fiberoptic Cable Corp., and Valtec Fiberoptics), polymethyl-methacrylate core fibers (DuPont CROFON and PFX), and polystyre… more

Date: November 1, 1976

Creator: Skoog, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

X-ray-induced chromosome aberrations in the leukocytes of mouse and man

In our earlier studies we showed that the frequency of dicentrics induced by x-rays in human leukocytes was about twice that induced in mouse leukocytes. The frequencies of deletions were similar in both species. However, the mouse cultures were fixed at 60 hrs and the human cultures at 54 hrs. In both cases it was likely that some of the cells analyzed were in their second post-treatment mitosis. Further studies were carried out using fixation times of 48 hrs for both human and mouse cultures.… more

Date: January 1, 1977

Creator: Preston, R. J. & Brewen, J. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, July--September 1975

Twenty-one coal samples have been collected and characterized. Sixty coals have been provided to other agencies at their request. The capability of controlling coal characteristics during preparation is being developed: large variations in volatile content occur within a given raw coal but, by controlling the preparation, a uniform product with the devised specifications can be produced. Studies have begun on the suitability of various coals and cokes for use in pressurized fixed bed gasifiers.… more

Date: December 1, 1975

Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Roles of scattered radiation in SRIXE

The scattering of x-rays is the major source of background and hence is a limiting factor in the minimum detectable limits available with SRIXE measurements. The scattering can be utilized for normalizing the net peak areas to fluctuations in sample thickness or mass on a relative basis or on a comparative basis. Even then measurement of the scattered x-rays should be made at backward angles. Measurement at forward angles should be avoided because of diffraction problems. The uncertainties in t… more

Date: January 1, 1988

Creator: Hanson, A. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Remarks on the radiation chemistry of radiation damage in cells. [X radiation, electrons]

Several models of the actions of compounds that sensitize cells to x-irradiation are reviewed and commented on. The electron sequestration model is described in detail and typical experimental results upon which it is based are reviewed. The varieties of responses induced by a number of sensitizers and their antagonists are stressed; there is no single, simple chemical explanation that can account for all the results. However, the importance of the e/sup -//sub aq/ -- .OH relation is evident in… more

Date: January 1, 1975

Creator: Powers, E. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Decay of /sup 99/Mo

Relative intensities for K x-rays and gamma rays emanating from /sup 99/Mo in equilibrium with its /sup 99/Tc* daughter have been measured using several Ge photon detectors. Combining these intensities with an evaluated set of electron-conversion coefficients has provided a set of absolute intensities for the observed gamma rays. The absolute intensity for the dominant 140.5-keV gamma ray in /sup 99/Tc was determined to be 90.7 +- 0.6/100 /sup 99/Mo disintegrations for /sup 99/Mo decay in equil… more

Date: December 14, 1976

Creator: Dickens, J. K. & Love, T. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Flow cytogenetics: progress toward chromosomal aberration detection. [X Radiation]

Using clonal derivatives of the Chinese hamster M3-1 cell line, we demonstrate the potential of flow systems to karyotype homogeneous aberrations (aberrations which are identical and present in every cell) and to detect heterogeneous aberrations (aberrations which occur randomly in a population and are not identical in every cell). Flow cytometry (FCM) of ethidium bromide stained isolated chromosomes from clone 650A of the M3-1 cells distinguishes nine chromosome types from the fourteen present… more

Date: July 1, 1977

Creator: Carrano, A. V.; Gray, J. W. & Van Dilla, M. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Biomedical and Environmental Research Program of the LASL Health Division. Progress report, January--December 1975

Separate abstracts were prepared for the six sections of the report. (HLW)

Date: April 1, 1976

Creator: Petersen, D. F. & Sullivan, E. M. (comps.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail.

Date: April 28, 1976

Creator: Baldini, M G

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Characteristics of American coals in relation to their conversion into clean energy fuels. Quarterly technical progress report, October--December 1975

The actual coal gasification reaction is controlled diffusionally in the lower part of the bed and kinetically in the upper part of the bed. When closely size-graded pulverized coal particles undergo rapid devolatilization in a laminar flow reactor, the effect of heating-up time on weight loss is negligibly small. All other experimental conditions being equal, the smaller the particle, the greater is the weight loss. Reactivity of a char increases with increase in partial pressure of oxygen in … more

Date: February 1, 1976

Creator: Spackman, W.; Davis, A.; Walker, P. L.; Lovell, H. L.; Essenhigh, R. H.; Vastola, F. J. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Application of mammalian cytogenetics to mutagenicity studies. [Triethylone melamine, x radiation, gamma radiation, LET]

Studies on induction of chromosome damage in germ cells by triethylene melamine (TEM) included determination of frequencies of chromosomal aberrations observed in human leukocytes after treating different stages of the cell cycle with TEM, frequencies of chromatid aberrations in metaphase I oocytes and the female pronuclear chromosomes following treatment of female mice with TEM, and frequencies of labeled diplotene-diakinesis figures and chromosome abberations at various intervals after treatm… more

Date: January 1, 1977

Creator: Brewen, J. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of krypton-85 sources for the Bureau of Mines coal dust combustion analyzer. Operations Division final report. [Gaseous /sup 85/Kr encapsulated in Ta; x-ray source]

Americium-241 used as a radiation source in a field instrument for measuring coal concentrations in mine dust presents a contamination hazard if the instrument is damaged. Alternative source designs based on /sup 85/Kr were developed and evaluated. Krypton-85 beta particles were used to excite x-rays from a target and the x-rays were used in place of the /sup 241/Am gamma radiation. Output of sources using /sup 85/Kr foils was not high enough because the concentration of /sup 85/Kr in the foils… more

Date: June 1, 1976

Creator: Bradley, N. C.; Case, F. N.; Cutshall, N. H. & Haff, K. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

First wall response to energy disposition in conceptual laser fusion reactors

Discussed are energy depositions in the first wall of various proposed laser-fusion reactors and the effect of pulse time on the stress and temperature in the first wall. Simple models can be used to estimate the temperature and stress rise from x-rays and neutrons. More complex analysis is needed to estimate the response of the first wall to reflected laser light and the pellet debris.

Date: February 1, 1976

Creator: Hovingh, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Kinetic and biochemical studies on tumor growth. Final report, October 1, 1967--July 14, 1976. [X radiation, /sup 125/I tracer technique]

The normal growth kinetics and the recovery kinetics following therapeutic perturbations with drugs and x-irradiation for the mouse duodenal crypt cells and the S102F and slow line tumor cells have been studied in depth, the rationale being that a detailed understanding of these phenomena would enhance our knowledge about tumor biology per se and also expand our appreciation of how normal and malignant tissues respond to and recover from therapeutic insults. Hopefully, such knowledge will event… more

Date: unknown

Creator: Dethlefsen, L. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of core analysis procedures using x-ray computerized tomography

In a letter from John C. Lorenz of Sandia National Laboratories dated November 8, 1988, analyses of interest included. With the core received, measurements are not possible. Core must be loaded into a passive vessel to flow various fluids for permeability measurements. Because the core was slabbed and plugged, this was not possible. Microfractures or porosity distribution can also be seen by flowing two fluids with contrasting attenuation coefficients and using a subtractive imaging technique. … more

Date: December 30, 1988

Creator: Sharer, J. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Genetic effects of radiation. [Extrapolation of mouse data to man]

Data are reviewed from studies on the genetic effects of x radiation in mice and the extrapolation of the findings for estimating genetic hazards in man is discussed. Data are included on the frequency of mutation induction following acute or chronic irradiation of male or female mice at various doses and dose rates.

Date: January 1, 1976

Creator: Selby, P. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Some aspects of the mechanism of bacteriophage function. Final progress report. [Mechanisms of inactivation of bacteriophages by ionizing radiation]

Data are summarized from a ten-year study on the radiobiology of phages. The results showed that: phages are inactivated principally by damage to DNA; DNA damage is of two types, base damage and double-strand breakage; double-strand breakage may be lethal because of interruption within a gene, however in phage systems the damage is more fundamental in that only a single DNA fragment is injected into the host; E. coli phage T4 is relatively resistant to inactivation by x-rays; and the rate of pr… more

Date: June 12, 1977

Creator: Freifelder, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effect of aging and radiation in mice of different genotypes

Data are presented on the life span of nine inbred strains and five hybrid strains of mice based on 400 mice of each sex for inbred and 200 mice of each sex for hybrid. Some of these mice were exposed when 120 days old to 250 R or 450 R of x radiation delivered at a dose rate of 60 R/min. Data on strain, sample size, and mean survival times are presented in tables.

Date: January 1, 1976

Creator: Storer, J. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department