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Dive into the research topics where James R. Valentine is active.

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Featured researches published by James R. Valentine.


Toxicology and Applied Pharmacology | 1984

Two-year toxicity/carcinogenicity study of fresh-brewed coffee in rats initially exposed in utero.

Paul E. Palm; Elsie P. Arnold; M.Susan Nick; James R. Valentine; Thomas E. Doerfler

Fresh-brewed regular coffee at concentrations of 25, 50, and 100% was consumed ad libitum as the sole fluid intake of F1 Sprague-Dawley rats (55 male and 55 female/group), derived from P0-treated females which were provided 50% coffee for about 5 weeks prior to copulation and throughout gestation and lactation. P0 males, P0 control females, and two groups of F1 control rats received tap water. Ten rats/sex/level were killed and examined after 1 year; survivors were killed after 2 years. Smaller mean body weights (50 and 100% coffee concentrations) occurred with increased feed and liquid consumption. Mean serum alkaline phosphatase, bilirubin, BUN, and calcium values occasionally were elevated. Serum cholesterol levels at 2 years were elevated in males (25 and 100%) and at 1 and 2 years in females (100%). Bone calcium was slightly reduced in females consuming 25 or 100% coffee for 1 year, but not after 2 years. Treatment-related increases in relative weights of lungs, kidneys, liver, and epididymides were recorded. Significantly increased mortality was observed in females receiving 50 or 100% coffee. There also was some evidence of a relationship between coffee consumption and the number of primary tumor-bearing animals; however, this finding appeared ambiguous, dependent on the assumption that tumors were the probable cause of death.


Journal of the Air Pollution Control Association | 1975

Development of a High Purity Filter for High Temperature Particulate Sampling and Analysis

Arthur L. Benson; Philip L. Levins; Arthur A. Massucco; Donald B. Sparrow; James R. Valentine

This paper is directed to those interested in measuring trace metals in high-temperature particulate emissions. Particulate handsheet filters with satisfactory purity, efficiency, thermal stability, cost, strength (about 1 lb/in.), and flexibility for analysis of particulates in gases up to 800°C have been made with 99.2% Si02 Microquartzfibers. Almost all purity requirements for optimum atomic absorption and flame emission spectrophotometric analysis for trace metals have been achieved. The filters appear highly promising for X-ray fluorescence analysis but should be further evaluated. Suitability of the filters for neutron activation analysis is uncertain and should also be further evaluated. Dioctyl phthal-ate (DOP) aerosol efficiencies of 99 to 99.99% have been achieved by using fibers of various diameters. The filters are insensitive to humidity, insoluble In most acids and organic solvents. The handsheet filters have a slightly alkaline pH, but similar filters have been made on a papermaking machine...


Journal of the Air Pollution Control Association | 1972

Determination of Oxides of Nitrogen in Combustion Effluents with a Nitrate Ion Selective Electrode

J.N. Driscoll; A.W. Berger; J.H. Becker; J.T. Funkhouser; James R. Valentine

The nitrate ion selective electrode was investigated as an alternative approach to the present colorimetric determination of nitrate resulting from oxidative absorption of nitrogen oxides from combustion effluents. The electrode offers advantages of speed and relatively simple experimental procedure. Replicate measurements of 10−4–10−2M nitric acid solutions using bracketing standards show that the electrode approach is capable of good precision (coefficient of variation = ±4%). Comparison of a method utilizing the nitrate electrode with the more laborious phenol disulfonic acid method for the measurement of nitrogen oxides in both oil and gas fired combustion effluents showed agreement within 4% of the mean even in the presence of high levels of SO2. The correlation coefficient found for PDS vs nitrate electrode is 0.987.


international conference on evolvable systems | 1990

A volatile organics concentrator for use in monitoring Space Station water quality

Daniel J. Ehntholt; Itamar Bodek; James R. Valentine; Rudy Trabanino; Johanna E. Vincze; Richard L. Sauer

The process used to identify, select, and design an approach to the isolation and concentration of volatile organic compounds from a water sample prior to chemical analysis in a microgravity environment is discerned. The trade analysis leading to the recommended volatile organics concentrator (VOC) concept to be tested in a breadboard device is presented. The system covers the areas of gases, volatile separation from water, and water removal/gas chromatograph/mass spectrometer interface. Five options for potential use in the VOC and GC/MS system are identified and ranked, and also nine options are presented for separation of volatiles from the water phase. Seven options for use in the water removal/GC column and MS interface are also identified and included in the overall considerations. A final overall recommendation for breadboard VOC testing is given.


international conference on evolvable systems | 1991

The Development of a Volatile Organics Concentrator for Use in Monitoring Space Station Water Quality

Itamar Bodek; Daniel J. Ehntholt; Thomas J. Stolki; James R. Valentine; Rudy Trabanino; Johanna Webb; Richard L. Sauer

A breadboard concept of a volatile organics concentrator (VOC) is manufactured and tested for optimized water-quality analysis in a space environment. The VOC system is attached to a gas chromatograph/mass spectrometer to analyze the volatile chemicals relevant to the operation of Space Station Freedom. The preliminary tests include: (1) comparisons with analyses based on direct on-column injections of standards; (2) analyses of iodinated volatile organics; (3) comparisons of nitrogen vs helium as the chromatography carrier gas; and (4) measurements of collection efficiency. The VOC can analyze EPA method-624 analytes at comparable detection using flame-ionization detection and can analyze volatile iodinated compounds. The breadboard has good reproducibility and can use nitrogen as a carrier gas; good results are noted for the collection and concentration levels and for water removal.


Archive | 1997

Machine-readable optical disc with reading-inhibit agent

Philip E. Rollhaus; John R. Powell; Eric J. Carlson; Daniel J. Ehntholt; Irwin C. Winkler; Christopher J. Marmo; James R. Valentine


Archive | 1979

Process for recovering precious metals from bimetallic material

James R. Valentine; Ravindra M. Nadkarni


Archive | 1996

Chemical gas generator

Arthur Cortellucci; Itamar Bodek; Roy J. Grabski; James R. Valentine


international conference on evolvable systems | 1991

Development of a portable contamination detector for use during EVA

Peter E. Glaser; Gary Koger; Dale N. Larson; James R. Valentine; Joseph H. Brooks; Albert Copeland; Robert L. Frost


international conference on evolvable systems | 1998

Open Path Fourier Transform Infrared (OP-FTIR) Spectrometry as a Multi-Analyte Sensor for Spacecraft Air

Melissa D. Tucker; Rebecca C. Rowe; James R. Valentine

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Albert Copeland

Lockheed Missiles and Space Company

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Joseph H. Brooks

Lockheed Missiles and Space Company

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