565 research outputs found
Reduction of Furan and the Preparation of Tetramethylene Derivatives
During the study of the nitrogen heterocyclics, a convenient method of preparing δ-chlorovaleronitrile was desired. The synthesis developed involved the procedure of Gilman and Louisinian for decarboxylation of furoic acid. The furan obtained was reduced in the presence of palladous oxide palladium black giving a 95 per cent yield of tetrahydrofuran which was split with hydrogen chloride yielding 55 per cent of the theoretical tetramethylene chlorohydrin. Treatment of the chlorohydrin with phosphorus tribromide gave a 98 per cent yield of tetramethylene chlorobromide which gave a 52 per cent yield of δ-chlorovalero nitrile when reacted with sodium cyanide. The chemicals required and the operations involved lend themselves to the preparation of appreciable quantities
Waxy Corn a New Crop
When Japan took the Netherland East Indies, we not only lost our main supply of rubber and tin, but also our tapioca starch
Alcohol Motor Fuels
The proposal to encourage the use of power alcohol made from farm crops grown in the Continental United States, as an aid to agriculture, is not new. Since the last consideration, something more than ten years ago, anhydrous ethyl alcohol has become commercially available. This development makes it feasible to use alcohol-gasoline mixtures. The power alcohol project is thus placed upon a new basis and is worthy of a new consideration
Comparison of Numerical Schemes for a Realistic Computational Aeroacoustics Benchmark Problem
In this work, a nonlinear structured-multiblock CAA solver, the NASA GRC BASS code, will be tested on a realistic CAA benchmark problem. The purpose of this test is to ascertain what effect the high-accuracy solution methods used in CAA have on a realistic test problem, where both the mean flow and the unsteady waves are simultaneously computed on a fully curvilinear grid from a commercial grid generator. The proposed test will compare the solutions obtained using several finite-difference methods on identical grids to determine whether high-accuracy schemes have advantages for this benchmark problem
Unsteady Validation of a Mean Flow Boundary Condition for Computational Aeroacoustics
In this work, a previously developed mean flow boundary condition will be validated for unsteady flows. The test cases will be several reference benchmark flows consisting of vortical gusts convecting in a uniform mean flow, as well as the more realistic case of a vortical gust impinging on a loaded 2D cascade. The results will verify that the mean flow boundary condition both imposes the desired mean flow as well as having little or no effect on the instantaneous unsteady solution
The Effect of Steffen Waste on the Fermentation of Pentosans from the Corn Stalk
It was found that Steffen waste furnishes a suitable source of nitrogen, salts, and buffers for the growth of Aerobacter pectinovorum on pentosan material prepared from corn-stalks
The Production of Propionic Acid from Pentoses by Propionibacterium pentosaceum
Propionibacterium pentosaceum attacks pentoses (xylose, arabinose) with the production of propionic and acetic acids
Anthropogenic versus fish‐derived nutrient effects on seagrass community structure and function
Humans are altering nutrient dynamics through myriad pathways globally. Concurrent with the addition of nutrients via municipal, industrial, and agricultural sources, widespread consumer exploitation is changing consumer‐mediated nutrient dynamics drastically. Thus, altered nutrient dynamics can occur through changes in the supply of multiple nutrients, as well as through changes in the sources of these nutrients. Seagrass ecosystems are heavily impacted by human activities, with highly altered nutrient dynamics from multiple causes. We simulate scenarios of altered nutrient supply and ratios, nitrogen:phosphorus (N:P), from two nutrient sources in seagrass ecosystems: anthropogenic fertilizer and fish excretion. In doing so we tested expectations rooted in ecological theory that suggest the importance of resource dynamics for predicting primary producer dynamics. Ecosystem functions were strongly altered by artificial fertilizer (e.g., seagrass growth increased by as much as 140%), whereas plant/algae community structure was most affected by fish‐mediated nutrients or the interaction of both treatments (e.g., evenness increased by ~140% under conditions of low fish nutrients and high anthropogenic nutrients). Interactions between the nutrient sources were found for only two of six response variables, and the ratio of nutrient supply was the best predictor for only one response. These findings show that seagrass structure and function are well predicted by supply of a single nutrient (either N or P). Importantly, no single nutrient best explained the majority of responses—measures of community structure were best explained by the primary limiting nutrient to this system (P), whereas measures of growth and density of the dominant producer in the system were best explained by N. Thus, while our findings support aspects of theoretical expectations, the complexity of producer community responses belies broad generalities, underscoring the need to manage for multiple simultaneous nutrients in these imperiled coastal ecosystems.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/1/ecy2388_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/2/ecy2388-sup-0003-AppendixS3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/3/ecy2388-sup-0005-AppendixS5.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/4/ecy2388-sup-0006-AppendixS6.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/5/ecy2388-sup-0001-AppendixS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/6/ecy2388-sup-0002-AppendixS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/7/ecy2388.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145341/8/ecy2388-sup-0004-AppendixS4.pd
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