Showing papers by "Oregon State University published in 1977"

Threshold of sediment motion under unidirectional currents

Abstract: Carefully selected data for the threshold of sediment movement under unidirectional flow conditions have been utilized to re-examine the various empirical curves that are commonly employed to predict this threshold. After a review of the existing data, we employed only that data obtained from open channel flumes with parallel sidewalls where flows were uniform and steady over flattened beds of unigranular, rounded sediments. Without these restrictions, an unmanageable amount of scatter is introduced. This selected data is used to develop a modified Shields-type threshold diagram that extends the limits of the original diagram by three orders of magnitude in the grain-Reynolds number. The equally general but more easily employed Yalin diagram for sediment threshold is also examined. Although the Shields and Yalin diagrams are general in that they apply to a wide range of different liquids, in both cases somewhat different curves are obtained for threshold under air than for the liquids. The often used empirical curves of the friction velocity u,, the velocity 100 cm above the bed ul,,,,, the bottom stress T, and Shields’ relative stress Bt, all versus the grain diameter D, are limited in their ranges of application to certain combinations of grain density, fluid density, fluid viscosity and gravity. These conditions must be selected before the curves are generated from either the more general Shields or Yalin curves. For example, on the basis of the data selected for use in this paper, empirical threshold relationships for quartz density material in water are uloo = 122.6 Do.2B for D 0.2 crn where the velocity uloo measured 100 cm above the sediment bed is given in cmjsec and the grain diameter D is in cm. The limitations on any of the threshold relationships are severe. These limitations should be properly understood so that the empirical curves and relationships are not improperly employed.

Irradiance Measurements in the Upper Ocean

Abstract: Observations were made of downward solar radiation as a function of depth during an experiment in the North Pacific (35°N, 155°W). The irradiance meter employed was sensitive to solar radiation of wavelength 400–1000 nm arriving from above at a horizontal surface. Because of selective absorption of the short and long wavelengths, the irradiance decreases much faster than exponential in the upper few meters, falling to one-third of the incident value between 2 and 3 m depth. Below 10 m the decrease was exponential at a rate characteristic of moderately clear water of Type IA. Neglecting one case having low sun altitude, the observations are well represented by the expression I/I0=Rez/ζ1+(1−R)ezζ2, where I is the irradiance at depth −z, I0 is the irradiance at the surface less reflected solar radiation, R=0.62, ζ1 and ζ2 are attenuation lengths equal to 1.5 and 20 m, respectively, and z is the vertical space coordinate, positive upward with the origin at mean sea level. The depth at which the irrad...

Partition coefficient and bioaccumulation of selected organic chemicals

Abstract: An empirical equation is established to relate the experimental n-octanol/water partition coefficients to the aqueous solubilities of a wide variety of chemicals including aliphatic and aromatic hydrocarbons, aromatic acids, organochlorine and organophosphate pesticides, and polychlorinated biphenyls. Such a correlation, covering more than eight orders of magnitude in solubility (from 10-3 to 104 ppm) and six orders of magnitude in partition coefficient (from 10 to lo7), allows an assessment of partition coefficient from solubility with a predicted error of less than one order of magnitude. A correlation is observed between the bioconcentration factors in rainbow trout and the aqueous solubilities for some stable organic compounds.

Some Aspects of Wind Power Statistics

Abstract: Some of the problems of wind power statistics are examined. The exact relationship between the mean wind speed and the mean of the cube of the wind speed is discussed. The Weibull probability density function, a good model for wind speed distributions, leads to a Weibull model for the distribution of the cube of the wind speed. This model facilitates the computation of the mean and the standard deviation of the total wind power density, the usable wind power density, and the wind power density during the hours when an aerogenerator is operating. The Weibull model is applied to data from three Oregon wind power sites located in rugged terrain. It is concluded that the mean and standard deviation of the wind speed are the minimum statistics necessary for wind power estimates, that the Weibull model for the wind power density has many computational advantages, and that the existing wind power studies based solely on the total mean wind power density omit much valuable information about the wind powe...

Calcium oxalate: occurrence in soils and effect on nutrient and geochemical cycles.

Abstract: Whewellite and weddellite, calcium salts of oxalic acid, have been found in the litter layer of several different soils, indicating that oxalate is a major metabolic product of fungi in natural environments. The presence of oxalate in soil solution speeds weathering of soil minerals and increases the availability of nutrients to vegetation.

Rb-Sr and K-Ar geochronometry of Mesozoic granitic rocks and their Sr isotopic composition, Oregon, Washington, and Idaho

Abstract: Mesozoic orogeny and magmatism began in the northwestern United States soon after deposition of Permian strata, but no rocks have yet been dated from the Permian-Triassic orogenic period. Middle Triassic to Late Jurassic sediment sequences include major unconformities and evidence of several episodes of igneous activity. An early culmination of magmatism occurred in Late Triassic and Early Jurassic time (200–217 m.y. ago) in eugeosynclinal parts of far western Idaho. A widespread and intense culmination in Late Jurassic time was the final major orogenic event in the Oregon eugeosyncline. The Bald Mountain (147 to 158 m.y. old), Wallowa (probably 143 to 160 m.y. old but affected by Cretaceous metamorphism), Deep Creek (at least 137 m.y. old), and many other plutons in the Blue and Klamath Mountain regions in Oregon and in western Idaho were emplaced shortly before the end of Jurassic. The bulk of the Idaho batholith was emplaced during a Cretaceous culmination of igneous activity — the southern (Atlanta) lobe about 75 to 100 m.y. ago and the northern (Bitterroot) lobe about 70 to 80 m.y. ago. Much of the batholith was affected by Eocene magmatism which resulted in widespread resetting of isotopic dates for older rocks to values of 50 m.y. or less. Between 55 and 70 m.y. ago, there was a lull in igneous activity in the northwestern United States. Sr isotope initial ratios change abruptly across a boundary in western Idaho from ∼0.7040 or less, to the west, to ∼0.7060 or greater, to the east. This change marks the boundary between Precambrian crust and Phanerozoic eugeosyncline. The geologic setting of the observed transition and its time independence suggest that it is due to contamination and assimilation processes involving magmas from the mantle and enclosing crustal rocks. Contamination of magmas with radiogenic Sr renders the Sr whole-rock isochron technique useless in dating the Idaho batholith and other intrusive rocks in central and eastern Idaho, areas underlain by Precambrian basement.

The 2-Thiobarbituric Acid Reaction, An Objective Measure of the Oxidative Deterioration Occurring in Fats and Oils

Abstract: More than 30 years ago Kohn and Liver sedges' noted that aerobic oxidation of brain tissue produced a compound that when heated in an acid solution with 2-thiobarbituric acid (TBA) gave a brilliant red color with an absorption maximum at 532 nm. They postulated that the TBA reactive material was a carbonyl compound since the reaction was blocked by semicarbazine or phenylhydrazine. Bernheim et al.2' isolated an impure red TBA

Morphology and tectonics of the inner rift valley at lat 36°50′N on the Mid-Atlantic Ridge

Abstract: A segment of the inner rift valley of the Mid-Atlantic Ridge was investigated in detail from the American submersible Alvin . Fifteen traverses were made across the floor and up the first major fault scarps in the valley walls. The asymmetric morphology of the inner floor is found to be the primary result of volcanic activity modified by tectonic activity. Analysis of the tectonic features revealed that the rift is evolving within a single stress field that has its least principal strain axis (the compressional axis) aligned with the valley axis of N20°E. This is in contrast to the direction normal to plate divergence (N0°E). The tectonic elements in the inner floor are primarily vertically dipping tension fractures, whereas the fault scarps of the flanking walls are closer to a 60° dip and reflect a component of downdip shear. The information base obtained from Alvin was broadened with information collected in the area with more conventional techniques. Through an analysis of this information, primarily the topography, it was possible to extrapolate the detailed observations obtained from the submersible to intervening areas to produce a comprehensive geological interpretation of the study area. An evolutionary model was developed which suggests that the inner rift is a product of axial volcanic activity. Shortly after formation, the original volcanic edifice is modified by vertical collapse, which leads to a reduction of the bottom relief. This process is reversed in the outer portions of the valley as uplift begins. Tensional extension changes into vertical shear as the volcanic blocks are incorporated into the walls and elevated. During the various stages of uplift, readjustment takes place on the terraces, which results in the preservation of the original volcanoes as recognizable units. This model, which spans 180,000 yr of inferred time, is examined in detail in an attempt to identify its weaknesses as well as to delineate the specific factual constraints upon which it is built. Alternate interpretations are proposed and tested in a similar fashion; the result is the identification of key problems that need to be solved.

Genesis and transformation of metalliferous sediments from the East Pacific Rise, Bauer Deep, and Central Basin, northwest Nazca plate

Abstract: Analytical data for northwest Nazca plate sediments can be described in terms of a mixture of hydrothermal, detrital, hydrogenous, and biogenous material. Fe, Mn, Cu, Zn, Ni, Ba, Si, and Al are more than 50 percent hydrothermal in East Pacific Rise samples from lat 10° to 25 °S. The first four elements are dominantly hydrothermal in the Bauer Deep and Central Basin as well. Seventy to 80 percent of the Ni, 60 to 80 percent of the Ba, and 30 to 60 percent of the Cu and Zn in Bauer Deep and Central Basin sediments are hydrogenous. Si, Ba, and Zn are dominantly biogenous on the northern East Pacific Rise crest, where more than one-third of the Cu also is derived from this source. Detrital Al and Si are dominant away from the rise crest, particularly in the Central Basin, where about 40 percent of the Fe and 15 percent of the Zn may also be detrital. Much of the hydrothermal Fe and biogenous Si have been transformed to an iron-rich smectite. The proportion of total Fe bound in this phase varies from less than 20 percent on the southern rise crest to about 40 percent in the Bauer Deep. The distribution of each element is governed by (1) supply from the four basic sources; (2) lateral transport by bottom currents moving east and then south across the northern East Pacific Rise and Bauer Deep to the Central Basin and moving west from the Peru Basin to the Central Basin; and (3) transformation of the unstable metalliferous hydroxides into more stable smectite and ferromanganese oxyhydroxides.

Survival of a psychrophilic marine Vibrio under long-term nutrient starvation.

Abstract: Ant-300, a psychrophilic marine vibrio isolated from the surface water of the Antarctic convergence, was starved for periods of more than 1 year. During the first week of starvation, cell numbers increased from 100 to 800% of the initial number of cells. Fifty percent of the starved cells remained viable for 6 to 7 weeks while a portion of the population remained viable for more than 1 year. During the first 2 days of starvation, the endogenous respiration of the cells decreased over 80%. After 7 days, respiration had been reduced to 0.0071% total carbon respired per hour and remained constant thereafter. After 6 weeks of starvation, 46% of the cellular deoxyribonucleic acid had been degraded. Observation of the cellular deoxyribonucleic acid with Feulgen staining before starvation showed the average number of nuclear bodies per cell varied from 1.44 to 4.02 depending on the age of the culture. A linear relationship was found between the number of nuclear bodies per cell and the increase in cell numbers upon starvation. Our data suggest that Ant-300 is capable of surviving long periods of time with little or no nutrients and is therefore well adapted for the sparse nutrient conditions of the colder portions of the open ocean.

Pyrrolizidine alkaloids: their occurrence in honey from tansy ragwort (Senecio jacobaea L.).

Abstract: The hepatotoxic alkaloids known to occur in tansy ragwort (Senecio jacobaea L.) are also present in honey produced from the nectar of this species. These alkaloids, which inclued senecionine, seneciphylline, jacoline, jaconine, jacobine, and jacozine, are potentially carcinogenic, mutagenic, and teratogenic and may pose health hazards to the human consumer.

Growth rules in the marine copepod genus Acartia1,2

Abstract: Supported by the Oregon State University Sea Grant College Program, under Office of Sea Grant (NOAA), 04-6-158-44004.

Neoplasms in rainbow trout, a sensitive animal model for environmental carcinogenesis*

Abstract: The following topics are discussed: susceptibility of rainbow trout (Salmo gairdneri) to aflatoxins and other mycotoxins; the Oregon test diet; carcinogenic effects of cyclopropenoid fatty acids; carcinogenic response of the rainbow trout embryo; metabolism of mycotoxins by rainbow trout; and pathogenesis of rainbow trout liver cancer. (HLW)

Misconceptions of probability: An experiment with a small-group, activity-based, model building approach to introductory probability at the college level

Abstract: The day-by-day observations made by the experimenter during one of the activity-based classes indicate that college students can learn to discover some elementary probability models and formulas for themselves while working on probability experiments in small groups. Furthermore, the effects of sample size upon measures of central tendency and variability can be learned by students working on activities such as those developed for the experimental course in this study. Making guesses for the probability of events and checking guesses with a hand-held calculator seems to help college students to be more cautious about probability estimates, and helps to make them aware about some of their own misconceptions about probability. Small-group problem solving, keeping a log of all class work and activities, and investigating the misuses of statistics all appeared to have a positive effect upon college students' attitudes towards mathematics, as indicated in the questionnaires filled out by the subjects in the experimental sections.

Structure and Transport of the Antarctic Circumpolar Current at Drake Passage from Short-Term Measurements

Abstract: Three-week average speeds from an array of current meter moorings which spanned Drake Passage were used in conjunction with geostrophic calculations to estimate the short-term transport of the Antarctic Circumpolar Current. Closely spaced hydrographic stations show that the current consists of three vertically coherent bands of relatively high speed within the generally eastward flow. These bands separate four water mass regimes which have distinct T-S relationships at depths above the core of the Circumpolar Deep Water. The geostrophic transport relative to 3000 db averaged 95×106 m3 s−1 for five transects of the Passage and is consistent with previous measurements. Referencing the geostrophic transport to the current meter measurements gives an adjusted transport of 124×106 m3 s−1 to the east. This estimate is about midway between values obtained in the two previous attempts to adjust relative transport through Drake Passage to observed velocities. The previous estimates are reconsidered and co...

Eye Movements in Curve Negotiation

Abstract: Eye movements and fixations of five drivers were recorded and superimposed on a videotaped recording of the dynamic visual scene as they drove on a two-lane rural road. The results showed that (1) on curved roads, the fixation pattern follows the road geometry, whereas on straight roads, the search behavior is less active, and most of the fixations are close to the focus of expansion. The results indicate that in driving through curves drivers direct foveal fixations to lateral placement cues rather than rely on peripheral vision; (2) the process of curve scanning begins in the approach zone prior to the curve itself, suggesting that perceptually the curve negotiating process precedes the curve by several seconds; (3) the search patterns on right and left curves are not symmetrical; visual excursions to the right on right curves are greater than eye movements to the left on left curves; and (4) fixation duration statistics may be related to accident rates on curves. Implications of this study for the location of curve warning signs are given.

Glacial/Interglacial response rate of subpolar North Atlantic waters to climatic change: the record in oceanic sediments

Abstract: Estimated rates of response of northeast Atlantic surface waters to large-scale palaeoclimatic changes have been reconstructed in two forms: (1) as changes through time of estimated temperature at selected points in space, and (2) as movements through space of the polar front during particular intervals in time. Three periods of rapid change between the glacial and interglacial climatic extremes were examined: a short cold episode during isotopic stage 7 (the next-to-last interglaciation); the deglacial warming into the last interglaciation at the isotopic stage 6/5 boundary; and the most recent deglacial warming into the present interglaciation at the isotopic stage 2/1 boundary. Changes in sea-surface temperature of 7-11 °G (estimated from transfer function analysis) are characteristically registered in these cores in a few thousand years. The corresponding temporal rates of cooling or warming recorded usually average 1-5 °C/1000 years (a) for the complete climatic shift. During local passage of the polar front, these rates are even higher. Regional advance and retreat rates of the polar front along a NW/SE axis from Cape Farewell, Greenland, to Spain characteristically range from 200 to 1600 m/a during these intervals. These estimates represent the rates of change presently recorded in the sediments. The actual (faster) rates of oalaeo-oceanographic change in the overlying North Atlantic surface waters will only be determined once the smoothing effects of vertical mixing can be removed.

Microscale temperature and velocity spectra in the atmospheric boundary layer

Abstract: High-frequency fluctuations in temperature and velocity were measured at a height of 2 m above a harvested, nearly level field of rye grass. Conditions were both stably and unstably stratified. Reynolds numbers ranged from 370000 to 740000. Measurements of velocity were made with a hot-wire anemometer and measurements of temperature with a platinum resistance element which had a diameter of 0[sdot ]5 μm and a length of 1 mm. Thirteen runs ranging in length from 78 to 238 s were analysed.Spectra of velocity fluctuations are consistent with previously reported universal forms. Spectra of temperature, however, exhibit an increase in slope with increasing wavenumber as the maximum in the one-dimensional dissipation spectrum is approached. The peak of the one-dimensional dissipation spectrum for temperature fluctuations occurs at a higher wavenumber than that of simultaneous spectra of the dissipation of velocity fluctuations. It is suggested that the change in slope of the temperature spectra and the dissimilarity between temperature and velocity spectra may be due to spatial dissimilarity in the dissipation of temperature and velocity fluctuations. The temperature spectra are compared with a theoretical prediction for fluids with large Prandtl number, due to Batchelor (1959). Even though air has a Prandtl number of 0[sdot ]7, the observations are in qualitative agreement with predictions of the theory. The non-dimensional wavenumber at which the increase in slope occurs is about 0[sdot ]02, in good agreement with observations in the ocean reported by Grant et al. (1968).For the two runs for which the stratification was stable, the normalized spectra of the temperature derivative fall on average slightly below the mean of the spectra of the remaining runs in the range in which the slope is approximately one-third. Hence the Reynolds number may not have always been sufficiently high to satisfy completely the conditions for an inertial subrange.Universal inertial-subrange constants were directly evaluated from one-dimensional dissipation spectra and found to be 0[sdot ]54 and 1[sdot ]00 for velocity and temperature, respectively. The constant for velocity is consistent with previously reported values, while the value for temperature differs from some of the previous direct estimates but is only 20% greater than the mean of the indirect estimates. This discrepancy may be explained by the neglect in the indirect estimates of the divergence terms in the conservation equation for the variance of temperature fluctuations. There is weak evidence that the one-dimensional constant, and hence the temperature spectra, may depend upon the turbulence Reynolds number, which varied from 1200 to 4300 in the observations reported.

Corticoid stress responses to handling and temperature in salmonids.

Abstract: Plasma corticoid concentrations in juvenile chinook salmon (Oncorhynchus tshawytscha) netted and confined in a small live-cage rose from approximately 100 ng/ml to about 500 ng/ml in 24 h, then fell to 250 ng/ml at 48 h. In juvenile chinook salmon dip netted into a bucket containing aerated water and sampled serially at 90-s intervals, plasma corticoids increased from < 10 ng/ml to approximately 100 ng/ml in 20 min. In juvenile cutthroat trout (Salmo clarki clarki) acclimated to 13 C and subjected to a rapid increase in water temperature to 26 C, plasma corticoid concentration increased from about 20 ng/ml to 70 ng/ml in 25 min and remained elevated for more than 3 h. Juvenile cutthroat trout acclimated to diurnal temperature cycles (13–23 C) had no substantial changes in plasma corticoid concentration throughout the cycles. Juvenile cutthroat trout acclimated to 23 C had the same initial corticoid concentration as cutthroat trout acclimated to 9 C. When both groups were subjected to identical ne...

Hydrodynamic properties of a rigid molecule: Rotational and linear diffusion and fluorescence anisotropy

Abstract: The fluorescence anisotropy of a general rigid body is formally the sum of five exponentials We show that, to a high degree of approximation, there are relationships between the five time constants As we define the time constants here, τ1 ≅ τ5, τ2 ≅ τ3, and τ1−1 + 3τ4−1 ≅ 4τ2−1 In practical cases, at most only three exponentials will be observed, and, of these, only two are independent Using a numerical integration procedure, Perrin's equations for the rotational and translational diffusion of a general ellipsoid are solved Rotational friction coefficients, frictional ratio, rotational relaxation times, and the five exponential terms in the fluorescence anisotropy are tabulated as functions of the axial ratios of the ellipsoid In principle, the three axes of a general ellipsoid may be determined by a simultaneous measurement of the anisotropy and the linear diffusion constant We examine, and illustrate, the effect of experimental error on such a determination

On the Analysis of Symmetrical Three-Line Microstrip Circuits

Abstract: The immittance parameters for the case of symmetrical coupled three-line microstrip or other inhomogeneous six-port structures are derived in terms of the normal modes of the coupled system. The analytical results obtained reduce to the heretofore known results when the line parameters are interrelated in a specified manner, and should be useful in the study and accurate design of three-line couplers and other microwave circuit elements.