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The Occupational Safety and Health Administration has advanced engineering controls over administrative controls and protective equipment to reduce exposures to chemicals in the workplace. The application of employee training and motivation programs (such as job safety analysis) to reduce exposures to chemicals has not been emphasized. To determine the effectiveness of such programs, a pilot project in an alkyl lead production facility was conducted with 35 employees in an effort to reduce exposures to organic and inorganic lead. Results after 12 months show a 40% reduction in lead-in-urine and a 24% reduction in lead-in-blood, both indicators of total exposure to organic and inorganic lead.

Postprandial changes in osmolality, mineral, and volatile fatty acid concentrations in rumen fluid were examined in three cattle fed six widely differing diets. Mineral concentrations varied with diet and postprandial time. However, net changes in postprandial mineral concentrations did not contribute significantly to changes in osmotic pressure. There was an effect of diet and time after feeding on concentrations of volatile fatty acids. Postprandial changes in osmotic pressure were primarily due to changes in concentrations of volatile fatty acids. Magnesium oxide and sodium bicarbonate were fed to sheep to increase the osmotic pressure in rumen fluid. The salt supplement decreased acetate, propionate, heat, and methane production. However, rumen water flux was unaffected by the salt supplementation. Diets which produce hypertonic rumen fluid due to high mineral and/or concentrations of volatile fatty acids may reduce fermentation in rumen.

Abstract Over 300 matrix and fracture acidizing treatments, utilizing a thermally stable acid gelling agent, were performed in carbonate formations, worldwide. The initial results of several treatments were presented earlier (Ref. 1). Since then, trends toward sustained increases in production have been documented and are presented. Reductions in production decline rates have resulted in improved recovery of reserves. Improved live acid penetration results from the effects of stable viscosity, retarded reaction rate and proper treatment design. In addition, the gelling agent must be non-damaging, requiring tolerance to calcium and magnesium ions in the spent acid during cleanup. A gelling agent is described that provides the features of thermal stability and solubility in the live and spent acid. Introduction Commercial utilization of hydrochloric acid for stimulating oil and gas production from carbonate reservoirs began in the early 1930's. The beauty of using acid in treating carbonates lies in it's utter simplicity. Injected at matrix rates, significant amounts of new permeability are generated, thus removing the effects of formation damage near the wellbore. Under fracturing conditions, substantial fracture conductivity is created through the dissolution of the fracture face. This apparent simplicity, however, belies a complexity of interrelated and interdependent factors that determine the success of it's application. During the past fifty six years, much of the technological developments in acidizing have focused on the understanding of the processes limiting treatment results, and on methods and materials that could be used to overcome these limitations. In particular, recent years have seen the development of viscosifiers for acid, which are intended to impart characteristics that, if present, would enhance treatment results by increasing live acid penetration. Many of these materials have been used with only limited success, due to their inherent instability in live or spent acid, or incompatibility with common additives and contaminants. In 1983, a polymer was introduced, which provides the desired characteristics of stable viscosity, acid retardation and compatibility with most of the common acid additives. It has since been successfully applied in more than 300 matrix and fracture acidizing treatments. This paper provides a description of this gelling agent and details of several case histories. Discussion A synthetic polymer has been developed for use as a viscosifying agent for hydrochloric acid, tested under extremes of field conditions and found to be successful in enhancing the results of carbonate acidizing treatments. This material (Polymer A) was originally developed as a thermally stable viscosifier for brine solutions containing calcium and magnesium ions. It's composition is designed to resist thermal degradation and hydrolysis at high temperatures. Early in it's development, it was recognized that Polymer A also resisted acid hydrolysis and could be effectively employed as an acid gelling agent. Polymer A is readily soluble in hydrochloric acid, and develops viscosity rapidly. Figure 1 illustrates the relationship between the polymer concentration and fluid viscosity. As would be expected, the relationship is non-linear, with viscosity increasing rapidly at the higher polymer concentrations. Polymer A is effective in all commonly used hydrochloric acid systems, and the viscosity is independent of acid concentration. It's resistance to thermal degradation and acid hydrolysis provides stable viscosity and continued solubility at elevated temperatures. P. 259^

Publisher Summary This chapter presents results of recently conducted experiments which are designed to provide biochemical information on the fundamental biological issue of cellular specialization in the central nervous system. The chapter examines the development of dynamic metabolic processes rather than the genesis of specialized structural characters or electrical signals. Three processes are studied in the developing cerebral cortex of the rat: (1) the turnover of neuronal and glial proteins, (2) the degradative reactions exhibited by the lysosomes of the neurons and the glial cells, and (3) the differential ability of the neurons and glial cells to utilize cellular substrates for energy generation. Recently a cell separation procedure is developed that makes possible the preparation of mutually uncontaminated fractions of neuronal cell bodies and intact glial cells from gram amounts of brain tissue. This procedure is given in the chapter to examine the changing labelling rates in vivo of neuronal and glial proteins during early postnatal development and the decay of radioactivity in these proteins after a single intracerebral administration of phenylalanine. Some results relevant to each of these processes are presented in the chapter.

Conditions for the operation of a fungal spore-continuous column process are described wherein sucrose inversion is used as a model detection system. ECTEOLA-cellulose, acting as a solid support, provided good retention and flow-rate characteristics in columns prepared with Aspergillus and Penicillium spores. Spore columns so prepared were stable and needed only a cursory washing before storage or re-use. Germination on the column was negligible. The interactions occurring between variations in spore concentration, substrate concentration, and flow rate are reported, including the effect each has upon product yield.

The experimental procedures used and the results obtained in studying the plateout of nongaseous fission products that may escape from a helium gas stream are discussed. Results show that significant quantities of high-activity fission products are volatilized from powdered uranium dioxide at 1800 deg F, and the gross activity for each of the materials (Nichrome, type 302 stainless steel, and quartz) exposed to the fission product vapors follows the same general pattern. Some indication is given that high nickel content promotes plateout at high temperatures as is shown by testing nickel, Nichrome, types 310 and 405 stainless steel, and quartz. Radioisotopes that were identified as being deposited on the specimens were iodine-131 and -133, molybdenum-99, ruthenium- 103, and tellurium-132. Plateout occurred on all of the materials exposed to the helium stream from 1700 to 400 deg F. (N.W.R.)

One capsule containing BeO-30 vol% UO/sub 2/ fuel pellets was irradiated to a uranium burnup of approximately 30,000 Mwd/t. The results of a microscopic examination and physical measurements made during the hot-cell examination of the capsule were described. (auth)

A model of the beam-beam interaction has been used to explain the discrepancy between the luminosity as derived from experimental counting rates versus the luminosity derived from beam measurements. The physical picture is that the beam-beam interaction distorts the lattice functions of the machine. These distortions change the real luminosity by altering the beam size at the IR. The calculated luminosity is also affected in that the lattice distortions cause beam parameters to be incorrectly determined. >

Liberal development policies for rural areas, aimed at improving economic conditions and helping corporations find more profitable production sites, are found to fit the traditional role of intervention by government to encourage private investment in underdeveloped areas. Two strategies used in Wisconsin are analyzed to determine the level of community support and compare the social and intellectual support for growth centers of community elites with non-elites. Results indicate the general public does not support the concept of planned growth centers, with primary opposition coming from professional and farm groups rather than the ''traditionalism'' that is often used to characterize the area. Those favoring growth-center policies are primarily elites, who tend to limit their support to development of their own community. Elites also favor consolidating community and county delivery of services. Data for the study consisted of 231 personal interviews with leaders of 32 small- and mid-size communities. Their responses were then compared with a random sampling of non-elites. 27 references. (DCK)

An inexpensive, e8siiy constructed b8hnce ~8s mrdc to measure pi8nt phytom8ss from clipped qu8dnts. It c8n be f8brhted from m8terhls gener8Uy 8v8hbie in developing countries 8nd, within the designed rmge, it is 8ccunte enough to provide reli8bie estimites of standing crop. Since b8i8acee 8re easily md inexpensively constructed they c8n be m8de in qu8ntity urd distributed to ioc8i extension 8gents urd f8rmers.