Solubility of metallic-salt in acid nutrients in acid fertilizer solutions of urea phosphate,urea sulfate and urea nitrate

Solubilities of individual metallic-salt micronutrients were determined at 0°C in saturated acid fertilizer solutions of urea phosphate, urea sulfate, and urea nitrate. By using the acid pH mechanism, less expensive metallic salts can be used with drip irrigation applications to supply specific micronutrient needs to crops.Solubility of the sulfates of Cu, Fe, Mn, and Zn varied with each acid solution. Solubility of the above sources in the urea sulfate solutions also varied with the amount of sulfate in solution. The solubility of molybdenum decreased with the acidic conditions of the urea nitrate acid solution but appeared to increase for the urea phosphate and urea sulfate acid solutions. Boron was only slightly soluble in all the acid solutions.     

Small scale BWR core debris eutectics formation and melting experiment

A small scale experiment has recently been performed at Oak Ridge under the auspices of the Boiling Water Reactor Severe Accident Technology (BWRSAT) program to provide information concerning the formation of mixtures during heatup of representative BWR reactor vessel bottom head debris and to determine the composition and melting temperatures of these mixtures. The initial structure of the bottom head debris layers modeled in the experiment was taken from the results of recent Boiling Water Reactor Severe Accident Response (BWRSAR) code predictions for the short-term station blackout accident sequence.The experimental results provide useful information concerning the mixtures formed and their proportions and properties. The observed run-off of a stainless steel-zirconium eutectic alloy supports the contention that the initial pour from a BWR reactor vessel would consists of molten metals at relatively low temperatures.     

Intravenous adenosine and lidocaine in patients with acute mycocardial infarction

TCRhigh cells are generated by the mainstream of T cell differentiation in the thymus, whereas TCRint cells (or NK1.1+ T cells) are generated extrathymically in the liver and by an alternative intrathymic pathway. It is still unknown how these T cell populations interact in vivo with each other. To investigate the interaction of TCRint cells with TCRhigh cells, we used congenitally athymic nude (B6-nu/nu) mice which carry only TCRint cells in all immune organs. When TCRhigh cells from B6-C-H-2bm12 (bm12) mice (i.e. I-Abm12) were injected into B6-nu/nu mice (i.e. 1-Ab), the expanding T cell population was a mixture of TCRhigh cells of donor origin and TCRint cells of recipient origin. However, 9 Gy-irradiated nude mice permitted a full expansion of TCRhigh cells which expressed the IL-2Ralpha+beta+ phenotype, namely, they were at the most activated state. These mice died of acute graft-versus-host disease (GVHD) within 5 days. On the other hand, non-irradiated nude mice suppressed the expansion of TCRhigh cells of donor origin and such TCRhigh cells continued to have the IL-2Ralpha(+/-)beta+ phenotype. These mice could survive but showed signs of chronic GVHD thereafter. In both situations, CD4+alphabeta T cells expanded irrespective of donor or recipient origin. These results suggest that TCRint cells in the recipient mice possess a regulatory function in relation to donor TCRhigh cells; as a result, fully activated TCRhigh cells acquired the IL-2Ralpha+beta+ phenotype and injured the host, but TCRhigh cells suppressed in vivo remained as the IL-2Ralpha(+/-)beta+ phenotype and only partially injured the host.     

Computation of non-unique solutions of elastic-plastic trusses

It has recently been shown that the solution to certain well-defined boundary value problems for elastic/perfectly-plastic structures is non-unique. The present paper is concerned with the ability of finite-element computer programs to handle such solutions. Some problems arising from non-uniqueness are documented and techniques for circumventing those problems are evaluated by exploring the response of the program NonSAP to a variety of trusses with non-unique solutions.     

Production of high-quality liquid fertilizers from wet-process acid via urea phosphate

A pilot-plant process is described that purifies wet-process phosphoric acid for the production of a high-quality urea-ammonium polyphosphate base solution. An intermediate product, crystalline urea phosphate, is produced from urea and merchant-grade (54% P₂O₅) wet-process phosphoric acid. The urea phosphate crystals contain only about 15 to 20% of the objectionable impurities (iron, aluminum, and magnesium) originally contained in the feed wet-process acid. The urea phosphate crystals are pyrolyzed, converting orthophosphate to polyphosphate with very little energy consumption. The resulting melt is dissolved and neutralized with ammonia to produce 14-29-0 liquid product of high polyphosphate content.     

A Survey of Computational Paradigms in Undergraduate Mechanical Engineering Education

Undergraduate mechanical engineering programs in the United States were surveyed to determine the usage of structured programming languages (such as C or FORTRAN) versus the use of computational software systems (such as Matlab or Mathcad). A survey form was e‐mailed to all mechanical engineering programs. The survey form was used to determine the following: (1) programming courses required, (2) use of structured programming in mechanical engineering curricula, (3) use of computational systems in mechanical engineering curricula, (4) junior‐level analysis courses required, and (5) computer ownership requirements. Seventy‐four responses, representing a good cross section (size, research mission, and geographical location) of mechanical engineering programs were received. The survey showed that about three‐fourths required at least one course in a structured programming language but that only about one‐third of the programs requiring a formal programming course used structured programming in two or more required courses. More than three‐fourths of all programs used computational systems such as Matlab or Mathcad, and about the same number required a junior‐level analysis course. Thirteen of the seventy‐four mechanical engineering programs that responded to the survey required students to own computers.