14,190 research outputs found

    High-performance light-weight electrodes for hydrogen-oxygen fuel cells

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    High performance light weight electrodes for hydrogen oxygen fuel cell

    Effects of infrequent dried distillers grain supplementation on spring-calving cow performance

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    Feed and supplement costs and the expenses associated with delivery of winter supplements account for a large proportion of the total operating expenditures for cow-calf producers. Cattle grazing low-quality dormant native range (<6% crude protein) typically are unable to consume sufficient protein from the forage base, which limits microbial activity and forage digestion. Supplemental protein often is required to maintain cow body weight and body condition score during the last trimester of pregnancy. Low cow body condition scores at calving are common and may negatively affect lactation, rebreeding rates, and calf weaning weight. Failure to maintain proper nutritional status during this period severely affects short-term cow performance, reduces overall herd productivity, and limits profit potential. The most effective means of supplying supplemental protein to cows consuming dormant native range is to provide a small amount of high-protein feedstuff (>30% crude protein). Dried distillers grains with solubles (DDGS) are a by-product of the ethanol refining process. Distillers grains supply the recommended 30% crude protein level, are readily available, and often are favorably priced compared with more traditional feedstuffs. With the rising costs of inputs in today’s cow-calf sector, reducing cost is necessary to maintain viability of the national cowherd. Reducing the frequency of supplementation results in less labor and fuel use, effectively reducing input costs; however, this is viable only as long as cow performance is maintained at acceptable levels. Therefore, the objective of this study was to examine the effects of infrequent supplementation of dried distillers grains with solubles on cow body weight and body condition score

    Uncertainty in Measurements of Distance

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    Ng and van Dam have argued that quantum theory and general relativity give a lower bound of L^{1/3} L_P^{2/3} on the uncertainty of any distance, where L is the distance to be measured and L_P is the Planck length. Their idea is roughly that to minimize the position uncertainty of a freely falling measuring device one must increase its mass, but if its mass becomes too large it will collapse to form a black hole. Here we show that one can go below the Ng-van Dam bound by attaching the measuring device to a massive elastic rod. Relativistic limitations on the rod's rigidity, together with the constraint that its length exceeds its Schwarzschild radius, imply that zero-point fluctuations of the rod give an uncertainty greater than or equal to L_P.Comment: 5 pages LaTe

    Substance and semantics in the auditor\u27s standard report

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    The most recent effort at restating the auditor\u27s standard report, SAS 58, is the most comprehensive statement of the auditor\u27s role that has ever been adopted. It is an acknowledgment that the previous report had become an ineffective communication of the audit function and was perhaps too cautious in circumscribing the auditor\u27s public responsibilities. This paper compares and analyzes the terminology of the standard report throughout the professions\u27s history with particular emphasis on the recent years leading up to SAS 58. An exhibit compares the parallel terminology and the social, economic and political issues that resulted in each revision. Additionally, some assessment of the potential future changes to the report are presented

    Text Type And Text Structure: An Analysis Of Three Secondary Informal Reading Inventories

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    Reading educators (Cheek & Cheek, 1983; Roe, Stoodt, & Burns, 1978) urge secondary teachers to use informal reading inventories (IRIs) in order to diagnose students\u27 reading problems and to place students in textbooks at appropriate levels to optimize instruction. Advice of this nature is surely well-intended; nevertheless, educators have reservations about the merits of available IRIs. For example, readability levels of IRI passages (Gerke, 1980), passage dependency of questions (Marr & Lyon, 1980; Tuinman, 1971), classification of questions (Shell & Hanna, 1981), scoring criteria (Bormuth, 1969), validity (Cooper, 1952; Powell, 1971), and allowable errors or miscues (Ekwall, 1971; Harris & Sipay, 1980) have been the focus of serious questions by reading researchers

    Calf health and performance during receiving is not changed by fence-line preconditioning on flint hills range vs. drylot preconditioning

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    Ranch-of-origin preconditioning can improve the welfare and performance of beef calves by decreasing the stress associated with weaning, transport, diet change, and commingling with other calves. Preconditioning methods that involve pasture weaning coupled with maternal contact (i.e., fence-line weaning) have been promoted as possible best management practices for minimizing stress. Prior studies focused on performance and behavior during preconditioning on the ranch of origin. Little information has been published relating to carryover effects of fence-line preconditioning compared with conventional drylot preconditioning on performance and behavior during feedlot receiving. Our objectives were to measure growth and health during a 28-day ranch-of-origin preconditioning phase and during a 60-day feedlot receiving phase among beef calves subjected to 1 of 3 ranch-of-origin preconditioning programs: (1) drylot preconditioning + dam separation, (2) pasture preconditioning + fence-line contact with dams, and (3) pasture preconditioning + fence-line contact with dams + supplemental feed delivered in a bunk. In addition, we recorded incidences of behavioral distress among these treatments during first 7 days of feedlot receiving

    Comparison of Measured and Calculated Specific Resistances of Pd/Pt Interfaces

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    We compare specific resistances (AR equals area A times resistance R) of sputtered Pd/Pt interfaces measured in two different ways with no-free-parameter calculations. One way gives 2AR(Pd/Pt) of 0.29 (0.03) fohm-m(2) and the other 0.17 (0.13) fohm-m(2). From these we derive a best estimate of 2AR(Pd/Pt) of 0.28 (0.06) fohm-m(2), which overlaps with no-free-parameter calculations: 2AR(predicted) of 0.30 (0.04) fohm-m(2) for flat, perfect interfaces, or 0.33 (0.04) fohm-m(2) for interfaces composed of 2 monolayers of a 50percent-50percent PdPt alloy. These results support three prior examples of agreement between calculations and measurements for pairs of metals having the same crystal structure and the same lattice parameter to within 1 percent. We also estimate the spin-flipping probability at Pd/Pt interfaces as 0.13 (0.08).Comment: 3 pages, 3 figures, submitted for publication New version has corrected value of delta(Pd/Pt

    Occurrence, Composition and Formation of Ruppia, Widgeon Grass, balls in Saskatchewan Lakes

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    Widgeon Grass (Ruppia maritima) is an aquatic vascular plant (Ruppiaceae) which has been the source for rare balls of plant material found at the shores of lakes on four continents. In North America, the lakes involved were in North Dakota, Oregon, and now northern and southern Saskatchewan. The formation of the balls has not been observed in nature, but similar balls have been produced in other studies with Posidonia or Turtle Grass (Hydrocharitaceae) fibers under the wavelike action in a washing machine. Our samples are from a saline lake in southern Saskatchewan (49°N), and an over 40-year-old sample from an unknown lake north of the boreal transition zone (52°N). Comparisons of the plant material with herbarium specimens confirm that the balls are almost entirely comprised of Ruppia maritima, with minor items including invertebrate animal parts, sand pebbles and feathers. The context in which the material was found is consistent with the proposition that they are formed by Ruppia inflorescences breaking apart, drifting to near shore due to wind and being rolled into balls by wave action
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