Journal articles: 'Sedimentation and deposition – Kansas'

1

deNoyelles, Frank, and Jude H. Kastens. "Reservoir Sedimentation Challenges Kansas." Transactions of the Kansas Academy of Science 119, no. 1 (January 2016): 69–81. http://dx.doi.org/10.1660/062.119.0110.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Miller, Keith B., and Ronald R. West. "Chaetetid skeletons as short-term records of physical disturbance events." Paleontological Society Special Publications 6 (1992): 212. http://dx.doi.org/10.1017/s2475262200007723.

Full text

Abstract:

The growth records of spongiomorph and colonial skeletons have great potential for revealing the short-term depositional dynamics of ancient shallow marine environments. The utility of such skeletons for understanding the type and frequency of physical disturbance is illustrated by chaetetid-bearing limestones from Pennsylvanian (Desmoinesian) cyclothems of southeastern Kansas. Individual chaetetids frequently contain growth-interruption surfaces that are marked by clay partings or encrusting overgrowths of epibionts. Such interruptions occur irrespective of the growth form of the chaetetids, although they are more conspicuous in laminar and domical growth forms with ragged margins. Growth forms with smooth margins and fewer interruptions are more commonly high domical to columnar. The latter occur in cleaner carbonates with higher rates of carbonate accumulation and little siliciclastic influx.Interruption surfaces, which may be accompanied by reorientation of skeletal growth, record significant depositional and erosive events during the life history of the chaetetids. Similar surfaces have been described from a variety of other organisms including stromotoporoids, fistuliporoid and trepostome bryozoans, and favositid corals. In most environments, physical disturbance events of this time scale are invariably destroyed by subsequent bioturbation or current reworking. For this reason, chaetetid skeletons provide a valuable means of inferring the frequency and intensity of physical distubance and the rate of sediment accumulation.The temporal significance of growth interruptions must be determined before their environmental significance can be assessed. Geometry of calicle growth at these surfaces is critical for recognizing the manner in which growth was reestablished. Colonization by the settling of larvae on a dead surface has a much different implication than rejuvenation from surviving calicles. The former could occur on long dead skeletal hardgrounds, and the latter indicates physical disruptions during the life of a single chaetetid. Clay partings and clay-filled calicles record mud burial events resulting in partial mortality, followed by rapid rejuvenation and overgrowth of the sediment. Encrustation of growth-interruption surfaces by auloporid corals, and more rarely bryozoans and stromatolitic algae, indicate prolonged exposure of the skeletal surface and subsequent recolonization. Interestingly, auloporid encrustation appears to be more common in clay-rich carbonates having evidence of more frequent and higher-energy disturbance events. Evidence of dissolution or biocorrosion of the skeletal surface may imply an even longer period of exposure between disturbance and recolonization.Local development of chaetetid mounds and biostromes also permits larger-scale environmental fluctuations to be recognized. Changes in growth form, typically associated with changes in clay content of the enclosing carbonates, appear to reflect fluctuations in clastic sediment influx and water turbidity. Subtle clay-rich intervals and unconformity surfaces are recognized within chaetetid-bearing units only a few meters thick. The thin sedimentation units thus defined appear to be correlative between outcrops separated by tens of kilometers.Close examination of spongiomorph and colonial skeletons therefore has the potential to shed light on depositional processes and environmental changes at time scales of tens to thousands of years normally inaccessible to paleoecologists.

APA, Harvard, Vancouver, ISO, and other styles

3

Stovin, Virginia R., and Adrian J. Saul. "Sedimentation in Storage Tank Structures." Water Science and Technology 29, no. 1-2 (January 1, 1994): 363–72. http://dx.doi.org/10.2166/wst.1994.0684.

Full text

Abstract:

Although storage tanks provide an effective means of reducing the magnitude and frequency of combined sewer overflow discharges, and thereby of alleviating urban watercourse pollution, poorly designed storage structures frequently suffer from maintenance problems arising from sedimentation. The development of design guidelines that optimise the self-cleansing operation of storage structures is clearly a priority for urban drainage research. This paper describes a system that has been developed to study sediment deposition in laboratory model-scale storage structures. The patterns of deposition resulting from a selection of flow regimes are described, and the need for time-varying and time series storm tests is highlighted. Sedimentation patterns are shown to predominantly depend on the flow field, and the critical bed shear stresses for deposition and erosion in the model situation are identified. Hence, the potential application of numerical models to the design problem is discussed.

APA, Harvard, Vancouver, ISO, and other styles

4

YU, C. P., B. ASGHARIAN, and B. M. YEN. "Impaction and Sedimentation Deposition of Fibers in Airways." American Industrial Hygiene Association Journal 47, no. 2 (February 1986): 72–77. http://dx.doi.org/10.1080/15298668691389388.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Bonnas, Sylvia, Jan Tabellion, and Jürgen Haußelt. "Effect of Particle Size Distribution and Sedimentation Behaviour on Electrophoretic Deposition of Ceramic Suspensions." Key Engineering Materials 314 (July 2006): 69–74. http://dx.doi.org/10.4028/www.scientific.net/kem.314.69.

Full text

Abstract:

By systematic interaction of sedimentation and electrical field in electrophoretic deposition the particle size distribution of the deposited green body can be influenced. This can be employed for producing coatings with a very smooth surface by deposition of only the nanosized fraction of a conventional powder with broad or non-monomodal size distribution, thus avoiding preceding classification. In this paper, the preparation of stabilised slurries is described focussing on the criteria particle size distribution, zeta-potential and sedimentation behaviour. The effectiveness of the interaction of sedimentation and electrophoretic deposition is to be shown.

APA, Harvard, Vancouver, ISO, and other styles

6

Kerkweg, A., J. Buchholz, L. Ganzeveld, A. Pozzer, H. Tost, and P. Jöckel. "Technical Note: An implementation of the dry removal processes DRY DEPosition and SEDImentation in the Modular Earth Submodel System (MESSy)." Atmospheric Chemistry and Physics 6, no. 12 (October 12, 2006): 4617–32. http://dx.doi.org/10.5194/acp-6-4617-2006.

Full text

Abstract:

Abstract. We present the submodels DRYDEP and SEDI for the Modular Earth Submodel System (MESSy). Dry deposition of gases and aerosols is calculated within DRYDEP, whereas SEDI deals with aerosol particle sedimentation. Dry deposition velocities depend on the near-surface turbulence and the physical and chemical properties of the surface cover (e.g. the roughness length, soil pH or leaf stomatal exchange). The dry deposition algorithm used in DRYDEP is based on the big leaf approach and is described in detail within this Technical Note. The sedimentation submodel SEDI contains two sedimentation schemes: a simple upwind zeroth order scheme and a first order approach.

APA, Harvard, Vancouver, ISO, and other styles

7

Kerkweg, A., J. Buchholz, L. Ganzeveld, A. Pozzer, H. Tost, and P. Jöckel. "Technical Note: an implementation of the dry removal processes DRY DEPosition and SEDImentation in the Modular Earth Submodel System (MESSy)." Atmospheric Chemistry and Physics Discussions 6, no. 4 (July 24, 2006): 6853–901. http://dx.doi.org/10.5194/acpd-6-6853-2006.

Full text

Abstract:

Abstract. We present the submodels DRYDEP and SEDI for the Modular Earth Submodel System (MESSy). Gas phase and aerosol dry deposition are calculated within DRYDEP, whereas SEDI deals with aerosol particle sedimentation. Dry deposition velocities depend on the near-surface turbulence and the physical and chemical properties of the surface cover (e.g. the roughness length, soil pH or leaf stomatal exchange). The dry deposition algorithm used in DRYDEP is based on the big leaf approach and is described in detail within this Technical Note. The sedimentation submodel SEDI contains two sedimentation schemes: a simple upwind zeroth order scheme and a first order approach.

APA, Harvard, Vancouver, ISO, and other styles

8

Huang, Shu You, Zhi Gang Yin, Jin Guang Zhang, Yu Shan Ren, and Jing Hai Zhou. "Research the Problem about the Silted Deposition of the Broken Model." Applied Mechanics and Materials 204-208 (October 2012): 279–83. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.279.

Full text

Abstract:

On the foundation of the item that the residence flood controlled technique and standard tested and the analysis according to the formation of the sediment and the regulation of the sedimentation in the actual river. In the process of the studied item, design a kind of a new sedimentation basin in order to lower the sand carrying capacity of the down water in the limited distance and the biggest limit. Through the model experiment of this kind of the sedimentation basin and find out the result of the sink the sand under the different discharge, in order to guide the actual engineering application.

APA, Harvard, Vancouver, ISO, and other styles

9

Lee, H. N., and J. K. Shi. "An alternative approach for atmospheric plume deposition and sedimentation." International Journal of Environmental Studies 25, no. 1-2 (June 1985): 109–26. http://dx.doi.org/10.1080/00207238508710214.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Campos, Jody, Iran Eduardo Lima Neto, Ticiana Marinho Studart, and José Nilson Beserra Campos. "Influence of sediment distribution on the relationships among reservoir yield, spill, and evaporation losses." Engenharia Sanitaria e Ambiental 23, no. 5 (October 2018): 849–56. http://dx.doi.org/10.1590/s1413-41522018177058.

Full text

Abstract:

ABSTRACT This study shows how the sedimentation process in reservoirs affects the yield-spill-evaporation losses in reservoirs of Ceará State, Brazilian Northeast. Reservoirs are assumed to have, initially, inverted conical shape. Three forms of sedimentation were investigated: type 1, with deposition occurring parallel to the wetted perimeter; type 2, deposition distributed proportionally to the water depth; and, type 3, deposition concentrated in the reservoir bottom. These sedimentation patterns were found in many reservoirs in Ceará, with capacity ranging from about 0.5 to 100 hm3. Nevertheless, type 2 pattern was the most frequent. In this paper, five large reservoirs, over 100 hm3, were studied using Monte Carlo approach, and considering the silting over the time horizon. It was found that sediment distribution can significantly affect the yield-spill-evaporation trade-off on large reservoirs. Type 1 results have the lowest impact on reservoir yield, followed by type 2 and type 3. For Cedro reservoir, the yield would go to zero in 2115, assuming a type 3 deposition pattern. These results reinforce the need for monitoring sedimentation in large reservoirs in the Brazilian semiarid region. In addition, this study provides a relatively simple methodology to predict the impact of siltation on reservoir yield-spill-evaporation relationships, for the three most found patterns of sedimentation.

APA, Harvard, Vancouver, ISO, and other styles

11

Ren, Zhihui, Ting Wang, Yuanjian Wang, and Shaojun Qu. "A study on the characteristics and influencing factors of reservoir sedimentation in Wanjiazhai Reservoir." MATEC Web of Conferences 246 (2018): 01046. http://dx.doi.org/10.1051/matecconf/201824601046.

Full text

Abstract:

Based on measured data of the Wanjiazhai Reservoir in different periods, the characteristics of the spatial and temporal distribution of sedimentation in the reservoir area were preliminarily analyzed and the impact of reservoir operation on this distribution was discussed. Primary conclusions are as followed: in terms of temporal distribution, sedimentation continuously accumulated over the period from 2000 to 2017, with the sediment deposition ratio dramatically decreasing between 2011 and 2017; in terms of spatial distribution, the sedimentation in the reservoir area was mainly concentrated downstream of the WD54 section, with the highest concentration being downstream of the WD23 section. The characteristics of sedimentation distribution in the reservoir area were closely related to inflow and sediment conditions and reservoir operation water level. When the water level was lower than 952 m, the sediment deposition ratio was lower than 0. To further improve the sediment deposition form in the reservoir area, lowering water level and ejecting the sediment are recommended in a timely manner.

APA, Harvard, Vancouver, ISO, and other styles

12

Ismayilova, F. B. "Formation of sedimentation in oil mixing." Azerbaijan Oil Industry, no. 12 (December 15, 2020): 36–38. http://dx.doi.org/10.37474/0365-8554/2020-12-36-38.

Full text

Abstract:

As a result of the studies on the impact of the mixing of various sorts of Azerbaijani oils on their quality parameters, it was defined that in some correlations oil mixing is impossible as both rheological and physico-chemical parameters of these oils after mixing abnormally change. In the context of the oils from Bulla and Garachukhur fields it was specified that in 58:42 ratio percentage correspondingly, abnormal phenomenon is observed in parameter change. Moreover, various ballast deposition occurs due to the mixing. The paper studies the kinetics of deposition of different ballasts (resin, asphaltene and paraffins, as well as water, salt and mechanical impurities) in the mixture of incompatible oils. It was defined that the main mass of all ballasts is deposited during 8–10 hours. The studies justified that depending on the chemical composition of the oils, the incompatibility in the mixture may also be occured in intensive seperation of various ballasts.

APA, Harvard, Vancouver, ISO, and other styles

13

Markova, Irina, and Yuliya Bryanskaya. "Restrained fall velocity of suspended solids particles sedimentation in still water." E3S Web of Conferences 91 (2019): 07004. http://dx.doi.org/10.1051/e3sconf/20199107004.

Full text

Abstract:

The deposition rate is sufficiently studied in the case of single particles or in conditions of low concentrations of suspended matter, in which the precipitating particles do not affect each other. In the article, the method of calculation of the rate of the constrained deposition is offered, comparative calculations of the rate of the free and constrained deposition of particles are executed, the settlement results reflecting essential difference of the speed of the constrained and free deposition of particles are presented. The factors influencing the rate of confined deposition, among which the main one is the concentration of suspended matter in water, are considered. The experimental data confirming the reduction of speed of the constrained deposition of more than 3 times in a five-fold increase in the concentration of suspended solids is given. The dependence of the strained deposition rate of particles on the concentration of the suspension is obtained.

APA, Harvard, Vancouver, ISO, and other styles

14

Hanzlicek, Andrew S., Kenneth R. Harkin, Michael W. Dryden, Ruthanne Chun, Patricia A. Payne, Jerome C. Nietfeld, and Brad M. Debey. "Canine Schistosomiasis in Kansas: Five Cases (2000–2009)." Journal of the American Animal Hospital Association 47, no. 6 (November 1, 2011): e95-e102. http://dx.doi.org/10.5326/jaaha-ms-5580.

Full text

Abstract:

This is a retrospective case series consisting of five dogs diagnosed with schistosomiasis. The purpose of this article is to report the presence of naturally occurring canine schistosomiasis in Kansas and to provide clinical details regarding schistosomiasis. Medical records of dogs diagnosed with schistosomiasis from 2000 to 2009 were reviewed, and information extracted included signalment, history, clinical signs, diagnostic test results, treatment, and outcome. Affected dogs were primarily medium to large breed and young to middle aged. All dogs were considered outdoor dogs, with three having known access to surface water. Common clinical signs included gastrointestinal disease and signs associated with hypercalcemia. Fecal flotation was negative in all dogs in contrast to fecal saline sedimentation and fecal polymerase chain reaction, which were both positive in all dogs in which it was performed. All dogs treated specifically for schistosomiasis fully recovered. This article describes the first reported cases of canine schistosomiasis in the Midwest and the first reported case of intestinal intussusception secondary to schistosomiasis. Recognizing that canine schistosomiasis is present in Kansas and possibly other Midwestern states should prompt veterinarians to perform appropriate diagnostic investigation in suspect animals as the diagnosis is straight forward and relatively inexpensive.

APA, Harvard, Vancouver, ISO, and other styles

15

Pavlenko, Ivan, Marek Ochowiak, Praveen Agarwal, Radosław Olszewski, Bernard Michałek, and Andżelika Krupińska. "Improvement of Mathematical Model for Sedimentation Process." Energies 14, no. 15 (July 28, 2021): 4561. http://dx.doi.org/10.3390/en14154561.

Full text

Abstract:

In this article, the fractional-order differential equation of particle sedimentation was obtained. It considers the Basset force’s fractional origin and contains the Riemann–Liouville fractional integral rewritten as a Grunwald–Letnikov derivative. As a result, the general solution of the proposed fractional-order differential equation was found analytically. The belonging of this solution to the real range of values was strictly theoretically proven. The obtained solution was validated on a particular analytical case study. In addition, it was proven numerically with the approach based on the S-approximation method using the block-pulse operational matrix. The proposed mathematical model can be applied for modeling the processes of fine particles sedimentation in liquids, aerosol deposition in gas flows, and particle deposition in gas-dispersed systems.

APA, Harvard, Vancouver, ISO, and other styles

16

Layzell, Anthony L., Rolfe D. Mandel, Greg A. Ludvigson, Tammy M. Rittenour, and Jon J. Smith. "Forces driving late Pleistocene (ca. 77–12 ka) landscape evolution in the Cimarron River valley, southwestern Kansas." Quaternary Research 84, no. 1 (July 2015): 106–17. http://dx.doi.org/10.1016/j.yqres.2015.05.003.

Full text

Abstract:

This study presents stratigraphic, geomorphic, and paleoenvironmental (δ13C) data that provide insight into the late Pleistocene landscape evolution of the Cimarron River valley in the High Plains of southwestern Kansas. Two distinct valley fills (T-1 and T-2) were investigated. Three soils occur in the T-2 fill and five in the T-1 fill, all indicating periods of landscape stability or slow sedimentation. Of particular interest are two cumulic soils dating to ca. 48–28 and 13–12.5 ka. δ13C values are consistent with regional paleoenvironmental proxy data that indicate the prevalence of warm, dry conditions at these times. The Cimarron River is interpreted to have responded to these climatic changes and to local base level control. Specifically, aggradation occurred during cool, wet periods and slow sedimentation with cumulic soil formation occurred under warmer, drier climates. Significant valley incision (~ 25 m) by ca. 28 ka likely resulted from a lowering of local base level caused by deep-seated dissolution of Permian evaporite deposits.

APA, Harvard, Vancouver, ISO, and other styles

17

Kadko, David. "Late Cenozoic sedimentation and metal deposition in the North Pacific." Geochimica et Cosmochimica Acta 49, no. 3 (March 1985): 651–61. http://dx.doi.org/10.1016/0016-7037(85)90160-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Feng, Xiao Xiang, Zhe Liu, and Xing Kui Wang. "Application Comparison about Sediment Deposition in Outer Channel by Three-Layer Mode and Analog Analysis Mode." Applied Mechanics and Materials 130-134 (October 2011): 1638–44. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.1638.

Full text

Abstract:

Sudden sedimentation is an important subject for building ports in silt-sandy coast. It elaborates calculation methods detailed about three-layer deposition mode and analogy analysis mode. And they are used to predict the deposition in outer channel of Binzhou Port. Comparative results show that they are basically same on the distribution of sudden sedimentation, deposition thickness and volume along the channel. And it is larger from three-layer deposition mode than analogy analysis mode. The formal mode is propitious to project security. By analyzing the characteristics and applicability about two methods, basic law is obtained for sediment movement and predicting methods under strong wind in the outer channel of silt-sandy coast.

APA, Harvard, Vancouver, ISO, and other styles

19

Koster, Kay, Jan Stafleu, Peter C. Vos, and Michiel J. van der Meulen. "Can we elevate the subsiding coastal plain of the Netherlands with controlled sedimentation?" Proceedings of the International Association of Hydrological Sciences 382 (April 22, 2020): 767–73. http://dx.doi.org/10.5194/piahs-382-767-2020.

Full text

Abstract:

Abstract. Half the surface area of the coastal plain of the Netherlands has been subsiding below mean sea-level as a result of peatland drainage. At present, the low elevation is sustained, because sedimentation necessary to aggrade the coastal plain back to natural elevations is hampered by engineering structures. Alternatively, controlled sedimentation is a discussed method to elevate the coastal plain. This can either be achieved by allowing water courses to deliver sediments to designated areas, or by anthropogenic deposition. Here, we assess the possibilities of this strategy by determining whether natural systems or anthropogenic deposition are sufficient to elevate the surface to mean high water (MHW), taking into account IPCC projected minimum and maximum forecasted sea-level rise (RCP2.6 and RCP8.5), and predicted future subsidence. We use the 3D geological subsurface model GeoTOP to quantify sediments; i.e. clay and sand that were naturally delivered to the coastal plain by series of tidal inlets and the Rhine river system. Furthermore, we quantify the amount of anthropogenic deposition, and analyze documented supplies. Finally, we discuss the implications of controlled sedimentation in designated areas by providing examples of past embankment breaches. We quantify that 16.98 km3 of sediments are required to elevate the surface to MHW, and between 22.41 and 29.29 km3 at the end of the 21st century. We estimate that 45.30 km3 of sediments were delivered by the tidal systems during 3000 years (52 % sand), 20.18 km3 by the Rhine river system during 8000 years (29 % sand), and 3.59 km3 of anthropogenic deposition. We conclude that the coastal plain of the Netherlands cannot be elevated to more safe levels with controlled sedimentation. Exceptions are areas proximal to tidal systems with high sediment yields. Anthropogenic deposition, combining natural sedimentation with supplied sediments, or allowing peat growth in inundated areas could be viable alternatives as well as.

APA, Harvard, Vancouver, ISO, and other styles

20

van der Burg, Max Post, Karen E. Jenni, Timothy L. Nieman, Josh D. Eash, and Gregory A. Knutsen. "Understanding and Finding Solutions to the Problem of Sedimentation in the National Wildlife Refuge System." Journal of Fish and Wildlife Management 8, no. 2 (July 1, 2017): 648–60. http://dx.doi.org/10.3996/012016-jfwm-004.

Full text

Abstract:

Abstract The National Wildlife Refuge System (Refuge System) is a collection of public lands maintained by the U.S. Fish and Wildlife Service for migratory birds and other wildlife. Wetlands on individual National Wildlife Refuges (Refuges) may be at risk of increased sedimentation because of land use and water management practices. Increased sedimentation can reduce wetland habitat quality by altering hydrologic function, degrading water quality, and inhibiting growth of vegetation and invertebrates. On Refuges negatively affected by increased sedimentation, managers have to address complex questions about how to best remediate and mitigate the negative effects. The best way to account for these complexities is often not clear. On other Refuges, managers may not know whether sedimentation is a problem. Decision makers in the Refuge System may need to allocate resources to studying which Refuges could be at risk. Such analyses would help them understand where to direct support for managing increased sedimentation. In this paper, we summarize a case study demonstrating the use of decision-analytic tools in the development of a sedimentation management plan for Agassiz National Wildlife Refuge, Minnesota. Using what we learned from that process, we surveyed other Refuges in U.S. Fish and Wildlife Service Region 3 (an area encompassing the states of Illinois, Indiana, Iowa, Ohio, Michigan, Minnesota, Missouri, and Wisconsin) and Region 6 (an area encompassing the states of Colorado, Kansas, Montana, Nebraska, North Dakota, South Dakota, Utah, and Wyoming) about whether they experience sediment-related impacts to management. Our results show that cases of management being negatively affected by increased sedimentation are not isolated. We suggest that the Refuge System conduct a comprehensive and systematic assessment of increased sedimentation among Refuges to understand the importance of sedimentation in context with other management problems that Refuges face. The results of such an assessment could guide how the Refuge System allocates resources to studying and managing widespread stressors.

APA, Harvard, Vancouver, ISO, and other styles

21

Liverman, David G. E. "Sedimentation in ice-dammed Hazard Lake, Yukon." Canadian Journal of Earth Sciences 24, no. 9 (September 1, 1987): 1797–806. http://dx.doi.org/10.1139/e87-171.

Full text

Abstract:

"Hazard Lake," located in Kluane National Park, the Yukon, is an ice-dammed lake formed in 1966 by the surge of the Steele Glacier. Since 1975 it has drained annually by means of a subglacial tunnel. During July 1979, observations were made of lake processes before drainage and of sections described in the lake bottom after drainage. Three facies associations are believed to represent prelake, stable lake, and annual draining phases. Gravel commonly found at the base of sections represents deposition in a braided fluvial system prior to 1966. Lake sediments deposited between 1966 and 1975 are dominantly graded laminated silt deposited by turbid underflow from the major inflow stream. Lamination is probably caused by diurnal underflow events or daily variation in strength of underflow. No "winter" clay component of varved sediments is observed. During drainage a regressive sequence is deposited as the lake level drops, with sand-dominated sediments overlapping laminated silt where the main inflow stream enters the lake. This is followed by local fluvial deposition along the course of the reestablished stream. During filling a transgressive sequence is deposited as the lake level rises. Sand-dominated deltaic sedimentation is followed by deposition from underflow, resulting in laminated and massive silt and clay. These fine-grained facies separate sand facies and demark individual filling events but are easily eroded. Thus it is not possible to identify the effects of each individual drainage–filling cycle in the sediments. After drainage the lake remains empty until the next melt season, during which time a braided stream is established in the lake basin, depositing sands and gravels and eroding lake sediments.

APA, Harvard, Vancouver, ISO, and other styles

22

Bowen, Mark W., and William C. Johnson. "Sediment accumulation and sedimentation rates in playas on the High Plains of western Kansas, USA." Geomorphology 342 (October 2019): 117–26. http://dx.doi.org/10.1016/j.geomorph.2019.06.014.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Wang, Jianfu, Xin Kang, and Chunyin Peng. "Modelling and Experimental Investigation on the Settling Rate of Kaolinite Particles in Non-Ideal Sedimentation Stage under Constant Gravity." Materials 13, no. 17 (August 27, 2020): 3785. http://dx.doi.org/10.3390/ma13173785.

Full text

Abstract:

We compared the catalytic effects of two polymers (soluble starch and apple pectin) on the flocculation of kaolinite suspension. Moreover, the relationship between the zeta potential value and the time when kaolin particle sedimentation occurred was verified, and the mechanism of flocculation was analyzed. Additionally, a constitutive model was proposed to simulate the non-ideal sedimentation of clay particles in an aqueous system under constant gravity. This model not only considers the inhomogeneity of the solute but also simulates the change in clay concentration with time during the deposition process. This model proposes a decay constant (α) and sedimentation coefficient (s). The model can also be used to calculate the instantaneous sedimentation rate of the clay suspensions at any time and any depth for the settling cylinder. These sedimentary characteristics were simulated by adopting the established deposition model. The results show that the model is capable of predicting the time required for the complete sedimentation of particles in the aqueous system, suggesting the feasibility of engineering wastewater treatment, site dredging, etc.

APA, Harvard, Vancouver, ISO, and other styles

24

Darquenne, C., K. L. Zeman, R. C. Sá, T. K. Cooper, J. M. Fine, W. D. Bennett, and G. K. Prisk. "Removal of sedimentation decreases relative deposition of coarse particles in the lung periphery." Journal of Applied Physiology 115, no. 4 (August 15, 2013): 546–55. http://dx.doi.org/10.1152/japplphysiol.01520.2012.

Full text

Abstract:

Lung deposition of >0.5-μm particles is strongly influenced by gravitational sedimentation, with deposition being reduced in microgravity (μG) compared with normal gravity (1G). Gravity not only affects total deposition, but may also alter regional deposition. Using gamma scintigraphy, we measured the distribution of regional deposition and retention of radiolabeled particles (99mTc-labeled sulfur colloid, 5-μm diameter) in five healthy volunteers. Particles were inhaled in a controlled fashion (0.5 l/s, 15 breaths/min) during multiple periods of μG aboard the National Aeronautics and Space Administration Microgravity Research Aircraft and in 1G. In both cases, deposition scans were obtained immediately postinhalation and at 1 h 30 min, 4 h, and 22 h postinhalation. Regional deposition was characterized by the central-to-peripheral ratio and by the skew of the distribution of deposited particles on scans acquired directly postinhalation. Relative distribution of deposition between the airways and the alveolar region was derived from data acquired at the various time points. Compared with inhalation in 1G, subjects show an increase in central-to-peripheral ratio ( P = 0.043), skew ( P = 0.043), and tracheobronchial deposition ( P < 0.001) when particles were inhaled in μG. The absence of gravity caused fewer particles to deposit in the lung periphery than in the central region where deposition occurred mainly in the airways in μG. Furthermore, the increased skew observed in μG likely illustrates the presence of localized areas of deposition, i.e., “hot spots”, resulting from inertial impaction. In conclusion, gravity has a significant effect on deposition patterns of coarse particles, with most of deposition occurring in the alveolar region in 1G but in the large airways in μG.

APA, Harvard, Vancouver, ISO, and other styles

25

Maina, Caroline W., Joseph K. Sang, Benedict M. Mutua, and James M. Raude. "A review of radiometric analysis on soil erosion and deposition studies in Africa." Geochronometria 45, no. 1 (January 24, 2018): 10–19. http://dx.doi.org/10.1515/geochr-2015-0085.

Full text

Abstract:

Abstract Soil erosion is one of the main soil degradation phenomena that threaten sustainable use of soil productivity thus affecting food security. In addition, it leads to reservoir storage capacity loss because of sedimentation. This not only affects water quantity but also water quality. Worldwide, annual loss in reservoir storage capacity due to sedimentation is 0.5 to 1%. Similarly, about 27% of land in Africa is largely degraded by erosion. As a result, there is need to minimize soil erosion and deposition through site specific estimation of soil erosion and deposition rates in the reservoirs. To achieve this, Fallout RadioNuclides (FRNs) are some of the methods in use. The most common radionuclides include; 137Cs, 210Pb and 7Be. Only few countries in Africa have exploited these FRNs. In these countries, 137Cs has been largely exploited but in some regions, it has been reported to be below minimum detection limit. Using 137Cs and 210Pb, maximum reference inventory in Africa is found to be 1450 and 2602 Bq/m2, respectively. However, there is minimal application of 7Be within the continent. Also, very little has been done in Africa to assess chronology and sedimentation rates of reservoirs using FRNs measured from sediment cores. In conclusion, a gap still exists on FRNs application in Africa in assessing soil erosion, deposition and reservoir sedimentation.

APA, Harvard, Vancouver, ISO, and other styles

26

Castro, Clovis Barreira e., Bárbara Segal, Fábio Negrão, and Emiliano Nicolas Calderon. "Four-year monthly sediment deposition on turbid southwestern Atlantic coral reefs, with a comparison of benthic assemblages." Brazilian Journal of Oceanography 60, no. 1 (March 2012): 49–63. http://dx.doi.org/10.1590/s1679-87592012000100006.

Full text

Abstract:

High sedimentation is often related to stress in coral reef communities. Most southwestern Atlantic reefs are characterized by high sedimentation. However, there are no temporal series of sediment deposition rates. We evaluated sediment deposition, the sediment carbonate composition and coral and zoanthid covers on six reefs in Brazil over four-years. Sediment deposition rates varied from near zero to 233 mg cm-2 day-1, with peaks between August and December, and yearly averages ranging from nine to 104 mg cm-2 day-1. Deposition rates presented site-specific correlations with wind, indicating that resuspension must be a major factor. The presence of carbonates varied from 38% to 90%, with two sites showing seasonal differences. Benthic communities were fairly similar among sites, but the analyses suggested particular frequencies at each site. There was no significant correlation between sediment and benthic communities. However, Palythoa caribaeorum usually occur in high sediment deposition areas. Our results did not corroborate previous data that suggested that a 10 mg cm-2 day-1 would be a "critical limit for coral survival". Some coral reefs may be associated with high sedimentation environments including carbonatic fractions, but which does not per se hinder the development of southwestern Atlantic coral reef communities.

APA, Harvard, Vancouver, ISO, and other styles

27

Lee, S. S., and J. E. Penner. "Aerosol effects on ice clouds: can the traditional concept of aerosol indirect effects be applied to aerosol-cloud interactions in cirrus clouds?" Atmospheric Chemistry and Physics Discussions 10, no. 4 (April 21, 2010): 10429–62. http://dx.doi.org/10.5194/acpd-10-10429-2010.

Full text

Abstract:

Abstract. Cirrus clouds cover approximately 20–25% of the globe and thus play an important role in the Earth's radiation budget. This indicates that aerosol effects on cirrus clouds can have a substantial impact on the variation of global radiative forcing if the ice-water path (IWP) changes. This study examines the aerosol indirect effect (AIE) through changes in the IWP for a cirrus cloud case. We use a cloud-system resolving model (CSRM) coupled with a double-moment representation of cloud microphysics. Intensified interactions among the cloud ice number concentration (CINC), deposition and dynamics play a critical role in the IWP increases due to aerosol increases. Increased aerosols lead to increased CINC, providing increased surface area for water vapor deposition. The increased deposition causes depositional heating which produces stronger updrafts, and leads to the increased IWP. The conversion of ice crystals to aggregates through autoconversion and accretion plays a negligible role in the IWP responses to aerosols, as the sedimentation of aggregates. The sedimentation of ice crystals plays a more important role in the IWP response to aerosol increases than the sedimentation of aggregates, but, not more important than the interactions among the CINC, deposition and dynamics.

APA, Harvard, Vancouver, ISO, and other styles

28

Theol, Shaimaa A., Bert Jagers, F. X. Suryadi, and Charlotte de Fraiture. "The Role of Gate Operation in Reducing Problems with Cohesive and Non-Cohesive Sediments in Irrigation Canals." Water 11, no. 12 (December 6, 2019): 2572. http://dx.doi.org/10.3390/w11122572.

Full text

Abstract:

Sediments cause serious problems in irrigation systems, adversely affecting canal performance, driving up maintenance costs and, in extreme cases, threatening system sustainability. Multiple studies were done on the deposition of non-cohesive sediment and implications for canal design, the use of canal operation in handling sedimentation problems is relatively under-studied, particularly for cohesive sediments. In this manuscript, several scenarios regarding weirs and gate operation were tested, using the Delft3D model, applied to a case study from the Gezira scheme in Sudan. Findings show that weirs play a modest role in sedimentation patterns, where their location influences their effectiveness. On the contrary, gate operation plays a significant role in sedimentation patterns. Reduced gate openings may cause canal blockage while intermittently fully opening and closing of gates can reduce sediment deposition in the canal by 54% even under conditions of heavy sediment load. Proper location of weirs and proper adjusting of the branch canal’s gate can substantially reduce sedimentation problems while ensuring sufficient water delivery to crops. The use of 2D/3D models provides useful insights into spatial and temporal patterns of deposition and erosion but has challenges related to running time imposing a rather coarse modelling resolution to keep running times acceptable.

APA, Harvard, Vancouver, ISO, and other styles

29

Saraiva, L. B., C. G. Ribeiro Meneses, H. N. de Souza Melo, A. L. Calado Araújo, and H. Pearson. "Determination of the sedimentation constants for total suspended solids and the algal component in a full-scale primary facultative pond operating at high wind velocities under tropical conditions." Water Science and Technology 51, no. 12 (June 1, 2005): 213–16. http://dx.doi.org/10.2166/wst.2005.0465.

Full text

Abstract:

This study evaluated the amount, distribution and sedimentation constant of solids in a full-scale primary facultative pond operating mostly under high wind conditions and the contribution made by the algal biomass. Solids deposition rates were measured using sedimentation traps placed in the inlet and outlet zones of the pond. Most sludge accumulation occurred, not surprisingly, in the inlet zone A1 with a sludge volume of 9072 m3 accumulating over an operating time of approximately 3 years. However, sludge deposition within this zone was uneven and affected by wind action. Mean proportionality constant (K) values for solids sedimentation were 3.02 and 5.70 for depths of 50 cm and 100 cm respectively for A1. In contrast in zone A3, (the outlet zone), reduced K values of 1.38 and 3.22 were obtained for depths of 50 cm and 100 cm respectively. The algal sedimentation constant varied from 0.8 d−1 in zone A1 to 0.02 d−1 in A3. These data suggest that in this large facultative pond the wind, blowing predominantly from the direction of the outlets towards the pond inlets, had a greater influence on solids deposition than the bulk hydraulic flow and also kept the pond completely mixed for most of the time.

APA, Harvard, Vancouver, ISO, and other styles

30

Dun, Hongchao, Guowei Xin, Ning Huang, Guangtian Shi, and Jie Zhang. "Wind-Tunnel Studies on Sand Sedimentation Around Wind-Break Walls of Lanxin High-Speed Railway II and Its Prevention." Applied Sciences 11, no. 13 (June 27, 2021): 5989. http://dx.doi.org/10.3390/app11135989.

Full text

Abstract:

Wind-break walls along Lanxin High-Speed Railway II were studied and approved as effective measures to reduce strong wind damage to the high-speed trains. The results show that sand sedimentation on the leeward sides of wind-break walls along the railway within Gobi Desert could significantly threaten the operation safety of running trains. Different from the current sand sedimentation prevention measures without adequate consideration of the deposition process of airborne sand particles, this study revealed the mechanism of sand sedimentation on the leeward sides of three wind-break walls within different terrains. A series of wind-tunnel experiments were carried out to measure the horizontal velocity, number density, transport flux, and deposition rate of sand particles, and it was found that the horizontal speed of sand particles was first increased and then decreased on the railway track, and the peak speed over the concave subgrade was much smaller than those over convex and flat subgrades. The number density and horizontal sand flux were largest over the concave subgrade, and were the smallest over the convex subgrade. The sand particle deposition rate and distribution were also the largest within the concave subgrade, and some measures were also proposed to prevent sand sedimentation on the leeward sides of wind-break walls.

APA, Harvard, Vancouver, ISO, and other styles

31

Guo, Shuai Jie, Bao Tian Wang, Fu Hai Zhang, and Liang Chen. "Settlement and Consolidation Mechanism of Cohesive Sedimentation in Estuarine Environment." Advanced Materials Research 261-263 (May 2011): 1454–58. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1454.

Full text

Abstract:

Estuarine area is the intersection zone of river estuary, coastal and land-phase. Cohesive sediment deposition for mutation affects estuary channel transport and brings great challenges to dredging project. Consolidation indicators are closely related to sedimentation and dredging, and there are apparent errors in application of Terzaghi theory in cohesive sediment consolidation evaluation for large stain characteristics. Then it is necessary to modify some consolidation parameters to extend Terzaghi theory in cohesive sediment consolidation. Considering a whole process of sedimentation and consolidation, a unified equation can be established based on sediment deposition and consolidation theory. Equation parameters can be determined by the simulation test (settlement column experiment). According to the settlement curves and volume fraction distribution curves by simulation experiment, modified consolidation coefficient and the trends can be determined, and modified consolidation coefficient can apply in dredging and deposition project.

APA, Harvard, Vancouver, ISO, and other styles

32

Stratmann, Frank, Heinz Fissan, and Thomas Peterson. "Particle Deposition Onto a Flat Surface from a Point Particle Source." Journal of the IEST 31, no. 6 (November 1, 1988): 39–41. http://dx.doi.org/10.17764/jiet.1.31.6.n65256516m648901.

Full text

Abstract:

A series of two-dimensional calculations are performed to determine particle fluxes to wafers in a stagnation flow configuration. Mechanisms that influenced particle deposition included convection, diffusion, sedimentation, and thermophoresis. Particle deposition patterns resulting from a uniform freestream concentration are compared with deposition patterns from a narrow particle beam.

APA, Harvard, Vancouver, ISO, and other styles

33

Roushangar, Kiyoumars, and Roghayeh Ghasempour. "Prediction of non-cohesive sediment transport in circular channels in deposition and limit of deposition states using SVM." Water Supply 17, no. 2 (September 23, 2016): 537–51. http://dx.doi.org/10.2166/ws.2016.153.

Full text

Abstract:

Sedimentation in sewer pipes has a negative impact on the performance of sewerage systems. However, due to the complex nature of sedimentation, determining the governing equations is difficult and the results of the available classic models for computing bedload transport rate often differ from each other. This paper focuses on the capability of a support vector machine (SVM) as a meta-model approach for predicting bedload transport in pipes. The method was applied for the deposition and limit of deposition states of sediment transport. Two different scenarios were proposed: in Scenario 1, the input combinations were prepared using only hydraulic characteristics, on the other hand, Scenario 2 was built using both hydraulic and sediment characteristics as model inputs of bedload transport. A comparison between the SVM and the employed classic approaches in predicting sediment transport indicated the supreme performance of the SVM, in which more accurate results were obtained. Also it was found that for estimation of bedload transport in pipes, Scenario 2 led to a more valid outcome than Scenario 1. Based on the sensitivity analysis, parameters Frm and d50/y in the limit of deposition state and Frm in the deposition state had the more dominant role in prediction of bedload discharge in pipes than other parameters.

APA, Harvard, Vancouver, ISO, and other styles

34

Sehsah, E. M. E. "SPRAY SPECTRA, DEPOSITION AND SEDIMENTATION CHARACTERISTICS FOR LOW PRESSURE LIQUID ATOMIZERS." Misr Journal of Agricultural Engineering 27, no. 3 (July 1, 2010): 839–62. http://dx.doi.org/10.21608/mjae.2010.105748.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Markelonis, Andrew R., Joanna S. Wang, Bruno Ullrich, Chien M. Wai, and Gail J. Brown. "Nanoparticle film deposition using a simple and fast centrifuge sedimentation method." Applied Nanoscience 5, no. 4 (July 25, 2014): 457–68. http://dx.doi.org/10.1007/s13204-014-0338-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Hoque, Ashabul, Dipankar Kumar, Anip Kumar Paul, Masudar Rahman, Gour Chandra Paul, and Shin Ichi Aoki. "Sedimentation in Dune Forests, Mangrove Forests and CC Block System and Associated Topographic Changes." Journal of Bangladesh Academy of Sciences 43, no. 1 (July 16, 2019): 67–78. http://dx.doi.org/10.3329/jbas.v43i1.42235.

Full text

Abstract:

This paper is concerned with the deposition of sediment due to dune forests (Nakatajima dune, Japan) and CC block system on a riverbank (Padma, Bangladesh). Measurements of sediment deposition were carried out at Nakatajima dune, Japan and at Padma riverbank, Rajshahi, Bangladesh using Global Positioning System (GPS). 2442 m3 sediment migrates each year to the East side of Nakatajima dune by wind and the edge of the dune develops about 6-7 m/year due to the existence of forests. Sedimentation rate is also greater in shallower mangrove areas. The trapped sediment height varies from 8.0 to 10.0 cm in the mangrove-lined bank. Mangrove forests help to trap 25% more sedimentation at low tide than at high tide. On the other hand, only for setting up the CC block and groynes along the bank, the sedimentation rate is observed almost twice than that of the previous year. An analysis shows that there is a similarity of sedimentation among dune, beach forests, mangrove forests and CC blocks. Journal of Bangladesh Academy of Sciences, Vol. 43, No. 1, 67-78, 2019

APA, Harvard, Vancouver, ISO, and other styles

37

Cuddington, K., and P. R. Leavitt. "An individual-based model of pigment flux in lakes: implications for organic biogeochemistry and paleoecology." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 10 (October 1, 1999): 1964–77. http://dx.doi.org/10.1139/f99-108.

Full text

Abstract:

Vertical fluxes of pigments are used in limnology to monitor phytoplankton abundance, herbivore grazing, ecosystem efficiency, and historical changes in production. However, significant pigment degradation can occur during algal sedimentation. We used an individual-based model of pigment flux to quantify the relative importance of production and degradation as controls of pigment sedimentation. Pigment deposition increased with production, sinking rate, and phytoplankton depth and declined as lake depth and the depth of oxygen penetration increased. Unexpectedly, pigment sedimentation rate was not sensitive to variation in photooxidation rates, even though bleaching accounted for the second greatest amount of pigment loss. Digestion by zooplankton caused the most pigment degradation, but grazing increased pigment deposition when digestive losses were less than those due to oxidation of pigments in ungrazed cells. The model suggests that algal production may be underestimated in sedimentation studies that do not consider variability in water column depth. Further, comparisons with paleoecological analyses suggest that some inferred increases in production during lake ontogeny may arise from changes in regulation of pigment fluxes rather than from increased algal production.

APA, Harvard, Vancouver, ISO, and other styles

38

Tsuda, A., J. P. Butler, and J. J. Fredberg. "Effects of alveolated duct structure on aerosol kinetics. II. Gravitational sedimentation and inertial impaction." Journal of Applied Physiology 76, no. 6 (June 1, 1994): 2510–16. http://dx.doi.org/10.1152/jappl.1994.76.6.2510.

Full text

Abstract:

We studied the effects of alveolated duct structure on deposition processes for particle diameters > or = 1 micron. For such large particles, Brownian motion is insignificant but gravity and inertial forces play an important role. A Lagrangian description of particle dynamics in an alveolated duct flow was developed, and computational analysis was performed over the physiologically relevant range. At low flow rates gravity caused deposition. Gravitational cross-streamline motion depended on the coupled effects of curvature of gas streamlines and duct orientation relative to gravity. The detailed convective flow pattern was an important factor in determining deposition. At higher flow rates, inertial impaction contributed markedly to deposition. The curved nature of streamlines again played a major role on deposition, but duct orientation had little effect. In the medium range of flow rates, both gravitational and inertial forces simultaneously influenced particle motion. Particle inertia, per se, did not cause deposition but substantially suppressed gravitational deposition. The deposition mechanism was complex; contrary to what is often assumed in past analyses, the interaction between gravitational and inertial effects could not be described in a simple additive fashion. We conclude that the structure of the alveolar duct has an important role in gravitational sedimentation and inertial impaction in the lung acinus.

APA, Harvard, Vancouver, ISO, and other styles

39

Li, Yuhao, Bruce R. Sutherland, Murray K. Gingras, George W. Owttrim, and Kurt O. Konhauser. "A novel approach to investigate the deposition of (bio)chemical sediments: The sedimentation velocity of cyanobacteria–ferrihydrite aggregates." Journal of Sedimentary Research 91, no. 4 (April 22, 2021): 390–98. http://dx.doi.org/10.2110/jsr.2020.114.

Full text

Abstract:

ABSTRACT Sedimentation velocities of various chemical sediments are typically calculated using Stokes's law. However, applying it to chemical sediments that form in situ in the water column is not ideal because the particle properties do not fulfill many of the assumptions underpinning the applicability of Stokes' law. As a consequence, it has been difficult to predict the sedimentation rate of ancient chemical sediments, such as Precambrian banded iron formations (BIF), because their primary sediments likely comprised aggregates of ferric hydroxides, such as ferrihydrite [Fe(OH)3], and marine bacterial biomass, including cyanobacteria. In this work we use a new experimental method to address the mechanisms by which primary BIF sediment, formed by the oxidation of dissolved Fe(II) by O2 and simultaneously incubated with cyanobacterium Synechococcus sp., were deposited to the Archean ocean. Specifically, we formed the aggregates in situ over a wide range of initial pH and Fe(II) concentrations, continuously recorded the entire settling processes of aggregates under each condition, and then processed the data in MATLAB according to different settling mechanisms. Our results demonstrate that ferrihydrite–cyanobacteria aggregates settled to the ocean floor either through the formation of uniformly descending concentration fronts or through convective plumes. The sedimentation mechanism depended on both initial Fe(II) concentration and the pH. Correspondingly, two algorithms were developed to characterize the sedimentation velocity. These algorithms tracked the alteration of light intensity from low to high as sediments descended from an initially homogeneous state through a water tank, and as well calculated the average light intensity over time, from which vertical time series were constructed allowing calculation of the sedimentation velocity. Our method not only provides an accurate estimation of the in situ sedimentation velocity of cell–mineral aggregates, but also provides new insights into the physical mechanisms by which the primary sediments composing BIF were deposited.

APA, Harvard, Vancouver, ISO, and other styles

40

Dobson, Evan P., and Gerald L. Mackie. "Increased deposition of organic matter, polychlorinated biphenyls, and cadmium by zebra mussels (Dreissena polymorpha) in western Lake Erie." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 5 (May 1, 1998): 1131–39. http://dx.doi.org/10.1139/f97-321.

Full text

Abstract:

Biodeposition of organic matter, polychlorinated biphenyls (PCBs), and cadmium (Cd) by zebra mussels (Dreissena polymorpha) was investigated at five stations in the western basin of Lake Erie during the summer of 1992. Biodeposition rates at the five stations were determined by using sediment traps and converted to per unit area values to facilitate comparisons with natural sedimentation rates. Biodeposition of suspended material by zebra mussels was up to 8 times greater than sedimentation in the traps. Concentrations of organic matter, PCBs, and Cd were determined for the biodeposits and the sedimented material. There were no significant differences in concentration of organic matter, PCBs, or Cd between the two types of material. Biodeposition rates per unit area of organic matter, PCBs, and Cd were 8-10 times greater than corresponding values for natural sedimentation; therefore, the natural sedimentation processes of these factors appear to be greatly accelerated in the presence of zebra mussels. Results support the possibility that zebra mussels are altering contaminant movement in western Lake Erie, as well as clarifying the water column by removing suspended material.

APA, Harvard, Vancouver, ISO, and other styles

41

Ghorbani, Mohammad, and Milad Roushanafshar. "Electrophoretic Deposition of Titania Nanopowders." Key Engineering Materials 412 (June 2009): 77–82. http://dx.doi.org/10.4028/www.scientific.net/kem.412.77.

Full text

Abstract:

Titania Nanopowders were successfully deposited on stainless steel sheet by means of electrophoretic deposition method from titania suspension in which isopropanol was employed as a solvent and Triethanolamine as a dispersant. The effect of TEA addition on the stability of nanopowders in suspensions was examined by sedimentation test; in addition, Malvern zeta sizer was employed for determination their particle size. Electrophoretic Deposition was done at different deposition conditions of voltage (5-20 volts) and time (5-60 sec) and the scanning electron microscopy (SEM) was used to investigate the effect of suspension composition and deposition parameters on the microstructure of coatings. Furthermore, the effect of deposition parameters on the consistencies of different coatings was analyzed by Scanning Probe Microscope (SPM).

APA, Harvard, Vancouver, ISO, and other styles

42

Lee, S. S., and J. E. Penner. "Aerosol effects on ice clouds: can the traditional concept of aerosol indirect effects be applied to aerosol-cloud interactions in cirrus clouds?" Atmospheric Chemistry and Physics 10, no. 21 (November 4, 2010): 10345–58. http://dx.doi.org/10.5194/acp-10-10345-2010.

Full text

Abstract:

Abstract. Cirrus clouds cover approximately 20–25% of the globe and thus play an important role in the Earth's radiation budget. Therefore the effect of aerosols on cirrus clouds can have a substantial impact on global radiative forcing if either the ice-water path (IWP) and/or the cloud ice number concentration (CINC) changes. This study examines the aerosol indirect effect (AIE) through changes in the CINC and IWP for a cirrus cloud case. We use a cloud-system resolving model (CSRM) coupled with a double-moment representation of cloud microphysics. Intensified interactions among CINC, deposition and dynamics play a critical role in increasing the IWP as aerosols increase. Increased IWP leads to a smaller change in the outgoing LW radiation relative to that for the SW radiation for increasing aerosols. Increased aerosols lead to increased CINC, providing increased surface area for water vapor deposition. The increased deposition causes depositional heating which produces stronger updrafts, and leads to the increased IWP. The conversion of ice crystals to aggregates through autoconversion and accretion plays a negligible role in the IWP response to aerosols, and the sedimentation of aggregates is negligible. The sedimentation of ice crystals plays a more important role in the IWP response to aerosol increases than the sedimentation of aggregates, but not more than the interactions among the CINC, deposition and dynamics.

APA, Harvard, Vancouver, ISO, and other styles

43

Apak, S. N., W. J. Stuart, and N. M. Lemon. "COMPRESSIONAL CONTROL ON SEDIMENT AND FACIES DISTRIBUTION SW NAPPAMERRI SYNCLINE AND ADJACENT MURTEREE HIGH, COOPER BASIN." APPEA Journal 35, no. 1 (1995): 190. http://dx.doi.org/10.1071/aj94013.

Full text

Abstract:

The northeast-trending Nappamerri Syncline and its flanking high to the southeast, the Murteree-Nappacoongee (NM) Trend, show structural development throughout the deposition of the Permo-Triassic Cooper Basin sequences. Pre-existing topography, such as around Moomba, influenced early depositional patterns within the area. Rates of sedimentation were influenced by the rate of uplift of source areas around the basin, largely as a consequence of buckling. Periods of active tectonism resulted in non-deposition and stripping of sediments from uplifted blocks while deposition continued in deeper areas. Hangingwall blocks, pushed up along reverse faults, strongly influenced the areas of sedimentation and the facies being deposited. This is particularly evident along the NM Trend. Phases of uplift were immediately followed by increased sedimentation where fluvial deposition dominated. The effect of displacement along the northwest-trending basement lineaments was to subdivide the northeast trends into compartments which contain similar facies within each time slice. Adjacent compartments may display different facies and different tectonic histories. An inversion episode, particularly evident in the Big Lake/Moomba area, resulted in a reversal of the depocentre and was related to phases of Sakmarian compression.Facies distribution and sandstone percentage maps of the chronostratigraphic units of the Patchawarra Formation suggest that a northeast-trending major channel system entered this part of basin along the NW edge of the Murteree area.

APA, Harvard, Vancouver, ISO, and other styles

44

Lin, Chung-Po, Jonathon W. Lott, and Ashish J. Mehta. "TURBIDITY - SEDIMENTATION IN CLOSED-END CHANNELS." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 98. http://dx.doi.org/10.9753/icce.v20.98.

Full text

Abstract:

In order to investigate the mechanism by which turbidity currents cause sedimentation in closed-end channels such as pier slips or residential canals, a laboratory investigation using fine-grained sediments was carried out. Two similar flume systems were used, each consisting of a main channel carrying sediment-laden flow and an orthogonally placed closed-end channel with a gate at the entrance. Characteristics of the turbidity current and sediment deposition in the closed-end channel were investigated following gate opening. Behavioral similarities between turbidity current and non-settling gravity currents were observed. Several properties, e.g. suspension concentration, showed exponential-type decay with distance. The ratio of sediment settling velocity to the densimetric velocity was found to be a useful parameter for comparing different test results. A relationship for estimating the sediment influx through the entrance is presented.

APA, Harvard, Vancouver, ISO, and other styles

45

Henderson, Penny J. "Sedimentation in an esker system influenced by bedrock topography near Kingston, Ontario." Canadian Journal of Earth Sciences 25, no. 7 (July 1, 1988): 987–99. http://dx.doi.org/10.1139/e88-098.

Full text

Abstract:

Late Wisconsinan sand and gravel deposits on the Frontenac Arch, Ontario, record a major meltwater drainage system developed subglacially and subaqueously in one or more glacial lake phases of the Lake Ontario basin during retreat of the Laurentide Ice Sheet. Factors influencing channel location, morphology, and sediment deposition are ice flow direction and the Precambrian bedrock topography, in turn dependent upon bedrock structure and composition. Meltwater drainage across the Frontenac Arch is localized within a broad depression oriented approximately parallel to glacial flow. Sediment deposition within the regional depression follows ice-flow direction despite irregular bedrock relief, indicating formation of the meltwater system and associated sediments in three stages: (i) establishment of a continuous meltwater system subglacially under high hydrostatic pressure with minor erosion of underlying Precambrian bedrock; (ii) deposition of poorly sorted, coarse-grained sediment in cavities or channels associated with irregular bedrock topography; and (iii) deposition of several coalescing subaqueous outwash fans at the ice margin as the glacier receded from the area. The discontinuous nature of the deposits and the association of proximal to distal outwash fan facies within a deposit suggest that esker sedimentation occurred during periodic stabilization of the ice front during deglaciation.

APA, Harvard, Vancouver, ISO, and other styles

46

Kusumgar, Sheela, D. P. Agrawal, and Prabhakar Sharma. "Radiocarbon Chronology and Magnetic Susceptibility Variation in Kumaon Lake Sediments." Radiocarbon 31, no. 03 (1989): 957–64. http://dx.doi.org/10.1017/s0033822200012583.

Full text

Abstract:

This study was carried out to determine time controls of erosion and sedimentation in the catchment area and lakes of the Naini Tal district in the Kumaon Himalayas. We present here our preliminary data from five lakes, Beon Tal, Garud Tal, Sukha Tal, Bhim Tal and Kamal Tal (Naukuchia Tal). A number of 14C dates are now available to estimate the sedimentation rate of the five lakes and magnetic susceptibility (xL; xfd) variation to determine the signature of sediment source. High xfd values indicate a higher proportion of soil component generally characterized by a slower rate of deposition, and low xfd values with a higher rate of sedimentation indicate rock-debris-derived sediment. A 14C chronology enables us to estimate the mean sedimentation rate whereas rock magnetic properties help us to characterize the type of source responsible for sedimentation.

APA, Harvard, Vancouver, ISO, and other styles

47

Isdarmanto, Isdarmanto, and Oentoeng Soebyanto. "ANALISIS POTENSI PANTAI GLAGAH SEBAGAI EKOWISATA UNGGULAN DI KABUPATEN KULONPROGO." Kepariwisataan: Jurnal Ilmiah 12, no. 02 (May 31, 2018): 1–12. http://dx.doi.org/10.47256/kepariwisataan.v12i02.82.

Full text

Abstract:

Glagah Beach is one of the most potential beaches and has the uniqueness as the charm and excellence of other southern seas. Glagah Beach located in Kulon Progo Regency is the only beach in Java that has a breakwater and has a lagoon on the edge of the sea separated by the sea so that large waves do not reach the lagoon. According to the typology of Glagah beach it self can be included in the classification of marine deposition coast. This is because the beach is formed due to the deposition deposition of river sedimentation material to the sea. This condition can be indicated by the emergence of a barrier coast emerging due to sedimentation from the river that empties into the location, then subject to marine effects that result in the formation of the lagoon. The process of sedimentation that occurs due to the flow and sedimentation of the river mouth that causes sedimentation in the coastal area. Qualitative research methods used with data collection techniques in the form of observation, interviews, documents, and various sources of data so it can be more clearly known geographical aspects of Glagah Beach, tourism profile, tourist visit conditions, tourism potential Glagah Beach, and to know the constraints which faced Glagah Beach tourism object and how the development strategy of Glagah Beach tourist attraction area in the future. Glagah Beach is a natural attraction that has the privilege and excellence compared to other beaches in Yogyakarta that need to keep the sustainability and need to be managed more effectively by the community and the local government as a policy holder so Glagah Beach became one of the leading ecotourism object which is interesting in Kulon Progo Regency Yogyakarta. Keywords: Glagah Beach; Sea Lagoon; Barrier Coast

APA, Harvard, Vancouver, ISO, and other styles

48

Podsetchine, V., and T. Huttula. "Modelling Sedimentation and Resuspension in Lakes." Water Quality Research Journal 29, no. 2-3 (May 1, 1994): 309–42. http://dx.doi.org/10.2166/wqrj.1994.020.

Full text

Abstract:

Abstract A 2-D vertical flow and suspended matter transport model and a 3-D transport model are described. Existing parameterizations of resuspension and deposition of sediments on the bottom are discussed. Models were applied for calculation of unsteady sediment transport in Lake Karhijärvi, Finland, for a five-day period with high winds and heavy rain in autumn 1992. A parabolic distribution of vertical eddy diffusivity was found to be applicable. Erosion was approximated with cubic dependence on bed shear stress. The 3-D model showed that the observed turbidity peak in the middle of the lake was caused by suspended matter transport through the River Susikoski. Sediment resuspension was found to be limited in the areas with depth less than 1 m. The 2-D vertical model was useful for determination of erosion under certain weather conditions, but for detailed analysis in space and time a 3-D model with high resolution is required.

APA, Harvard, Vancouver, ISO, and other styles

49

Park, Woncheol, Chanjong Yu, and Hayong Kim. "Sedimentation Management Plan for Ara Stream Navigation Waterway Using Soil Deposition Analysis." Korean Society of Hazard Mitigation 17, no. 6 (December 31, 2017): 463–72. http://dx.doi.org/10.9798/kosham.2017.17.6.463.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

韩, 吉薇. "Fabrication of Opal/Inverse Opal Structure by Vertical Deposition and Centrifugal Sedimentation." Material Sciences 07, no. 03 (2017): 353–61. http://dx.doi.org/10.12677/ms.2017.73048.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Sedimentation and deposition – Kansas'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles