An Idealized Model of Meandering Tidal River

Abstract An idealized model is proposed for heating of a pneumatic tire. A solution is obtained for the temperature rise of such a model. Using known thermal properties of rubber and known heat transfer coefficients, the time to reach thermal equilibrium is estimated.

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Effect of Salinity on Reaeration Coefficient of Receiving Waters

Water Science & Technology ◽

10.2166/wst.1984.0127 ◽

1984 ◽

Vol 16 (5-7) ◽

pp. 139-154 ◽

Cited By ~ 1

Author(s):

Ching-Gung Wen ◽

Jao-Fuan Kao ◽

Lawrence K Wang ◽

Chii Cherng Liaw

Keyword(s):

Saline Water ◽

Chloride Concentration ◽

Practical Method ◽

Tidal River ◽

Quality Analysis ◽

Flow Conditions ◽

Water Quality Analysis ◽

Design Engineers ◽

Reaeration Coefficient ◽

Receiving Waters

A practical method of determining reaeration coefficients would greatly aid design engineers in determining the degree of wastewater treatment required for a proposed effluent discharge. Many previous tidal river and estuary studies emphasized mainly the effects of flow conditions (such as velocity, water depth, turbulent intensity, hydraulic gradient, etc.) and temperature on stream aeration, and the effect of salts was not seriously considered. In this research a new mathematical model of reaeration coefficient considering the effect of salts has been developed for water quality analysis in tidal rivers and estuaries. The reaeration coefficient in saline water, k2s(day−1, base e) at any chloride concentration C(g/l) and at 20°C, can be expressed byin which k2f is the reaeration coefficient in fresh water at 20°C. The correlation coefficient of k2s/k2f and C is 0.88.

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Comparison of Cell Culture and a Poliovirus Gene Probe Assay for the Detection of Enteroviruses in Environmental Water Samples

Water Science & Technology ◽

10.2166/wst.1993.0366 ◽

1993 ◽

Vol 27 (3-4) ◽

pp. 311-314 ◽

Cited By ~ 7

Author(s):

Aaron B. Margolin ◽

Charles P. Gerba ◽

Kenneth J. Richardson ◽

Jaime E. Naranjo

Keyword(s):

Cell Culture ◽

Activated Sludge ◽

Water Samples ◽

Cdna Probe ◽

Culture Method ◽

Tidal River ◽

Nucleic Acid Hybridization ◽

Treated Wastewater ◽

Gene Probe ◽

Naturally Occurring

Nucleic acid hybridization provides a rapid non-cell culture method for the detection of enteric viruses in water. The purpose of this work was to compare the detection of naturally occurring enteroviruses by cell culture with their detection by a poliovirus gene probe in various types of water samples. Samples of activated sludge effluent, tertiary treated wastewater (activated sludge, filtration and passage through reverse osmosis), ground water, surface water and tidal river water were processed through 1 MDS Virozorb filters to concentrate any naturally occurring virus. Viruses were eluted from the filters with pH 9.5 beef extract and reduced in volume by flocculation to 20-30 ml. These concentrates were then assayed in the BGM cell line by the cytopathogenic effects (CPE) method and by a poliovirus cDNA probe (base pairs 115-7440) labeled with 32P. A total of 233 samples were assayed in this manner. In slightly more than 93% of the samples gene probe and cell culture yielded the same results. Of these samples 36 were positive by gene probe and 28 by cell culture assay. Positive samples for gene probe were confirmed by treatment with NaOH or RNAse and then reprobed. Samples demonstrating CPE upon primary passage were confirmed positive by subsequent passage of cell lysate on a new monolayer of BGM cells. Ten samples were positive by gene probe and negative by cell culture, and 4 samples were negative by gene probe and positive by cell culture.

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Physical and bacterial processes affecting suspended particulate matter in a tidal river

Water Science & Technology ◽

10.2166/wst.1998.0268 ◽

1998 ◽

Vol 38 (6) ◽

pp. 327-335

Author(s):

Yasunori Kozuki ◽

Yoshihiko Hosoi ◽

Hitoshi Murakami ◽

Katuhiro Kawamoto

Keyword(s):

Particle Size ◽

Particulate Matter ◽

Suspended Particulate Matter ◽

River Mouth ◽

Tidal River ◽

Natural Soil ◽

Size Change ◽

Run Off ◽

Suspended Particulate ◽

And Behavior

In order to clarify the origin and behavior of suspended particulate matter (SPM) in a tidal river, variation of SPM in a tidal river was investigated with regard to its size and constituents. SPM was separated into three groups according to size. Change of contents of titanium and organic substances of each group of SPM was examined. SPM which was discharged by run-off was transported with decomposition and sedimentation in a tidal river. Concentration of SPM with a particle size greater than 0.45 μm increased due to resuspension in a tidal river. Origin of SPM with a size of less than 0.45 μm at upstream areas was from natural soil and most of such SPM which had been transported settled near a river mouth. It was determined from examination of the CN ratio and the ratio of the number of attached bacteria to free bacteria that SPM with a size greater than 1.0 μm at upstream areas was decomposing intensively. At the downstream areas, SPM with a size of less than 0.45 μm came from the sea. SPM with particle size greater than 1.0 μm consisted of plankton and substances which were decomposed sufficiently while flowing.

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Measurement of Density Currents in an Idealized Model

Coastal Engineering 1970 ◽

10.1061/9780872620285.120 ◽

1970 ◽

Author(s):

Timm Stuckrath

Keyword(s):

Density Currents ◽

Idealized Model

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Crocodylus johnstoni and C. porosus Coexisting in a Tidal River

Wildlife Research ◽

10.1071/wr9830639 ◽

1983 ◽

Vol 10 (3) ◽

pp. 639 ◽

Cited By ~ 27

Author(s):

GJW Webb ◽

SC Manolis ◽

GC .Sack

Keyword(s):

Competitive Exclusion ◽

Dry Season ◽

Tidal River ◽

Main Stream ◽

Wet Season ◽

Seasonal Movements ◽

Crocodylus Johnstoni ◽

Seasonal Factors

A 52.5-km section of the Adelaide River, N.T. (12�13'S., 131�13'E.). was spotlight-surveyed 20 times between June 1979 and September 1981. C, johnstoni (15.3 � 9.2 sighted per survey) were less abundant than C. porosus (137.6 � 36.5 sighted per survey), and were mainly in the upstream 20 km of the survey route (96% of C. johnstoni sightings); here considered a zone of syntopy within the survey route. C. johnstoni congregate in the main stream during the dry season and disperse from it during the wet season, which parallels similar seasonal movements to and from dry-season refuges in non-tidal areas lacking C. porosus. As the dry season progresses, C. johnstoni are located further and further upstream, and this movement (or loss ofanimals) appears unrelated to changes in salinity. Numbers of C.johnstoni within the zone of syntopy are negatively correlated with numbers of C. porosus (r*2 = 0.50, P=0.005). and competitive exclusion may be occurring. Independent of seasonal factors, numbers of C. johnstoni within the zone of syntopy declined with consecutive month (1979-81: r*2=0.47, P= O.004), whereas numbers ofthe more recently protected C, porosus increased (r2 = 0.48, P= 0,006). The location of the syntopic zone was unchanged.

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Turbidity hysteresis in an estuary and tidal river following an extreme discharge event

10.1002/essoar.10502535.2 ◽

2020 ◽

Author(s):

David Keith Ralston ◽

Brian Yellen ◽

Jonathan D. Woodruff ◽

Sarah Fernald

Keyword(s):

Tidal River

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Along-wind dispersion by horizontal turbulent jets in the upper ocean

Journal of Physical Oceanography ◽

10.1175/jpo-d-20-0285.1 ◽

2021 ◽

Author(s):

Tobias Kukulka ◽

Todd Thoman

Keyword(s):

Turbulent Jets ◽

Surface Boundary ◽

Surface Boundary Layer ◽

Near Surface ◽

Idealized Model ◽

Eddy Simulation ◽

Wind Dispersion ◽

Shear Dispersion ◽

Coherent Jet ◽

Local Shear

AbstractDispersion processes in the ocean surface boundary layer (OSBL) determine marine material distributions such as those of plankton and pollutants. Sheared velocities drive shear dispersion, which is traditionally assumed to be due to mean horizontal currents that decrease from the surface. However, OSBL turbulence supports along-wind jets; located in near-surface convergence and downwelling regions, such turbulent jets contain strong local shear. Through wind-driven idealized and large eddy simulation (LES) models of the OSBL, this study examines the role of turbulent along-wind jets in dispersing material. In the idealized model, turbulent jets are generated by prescribed cellular flow with surface convergence and associated downwelling regions. Numeric and analytic model solutions reveal that horizontal jets substantially contribute to along-wind dispersion for sufficiently strong cellular flows and exceed contributions due to vertical mean shear for buoyant surface-trapped material. However, surface convergence regions also accumulate surface-trapped material, reducing shear dispersion by jets. Turbulence resolving LES results of a coastal depth-limited ocean agree qualitatively with the idealized model and reveal long-lived coherent jet structures that are necessary for effective jet dispersion. These coastal results indicate substantial jet contributions to along-wind dispersion. However, jet dispersion is likely less effective in the open ocean because jets are shorter lived, less organized, and distorted due to spiraling Ekman currents.

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