AERO: A Decision Support Tool for Wind Erosion Assessment in Rangelands and Croplands

Science.gov (United States)

Galloza, M.; Webb, N.; Herrick, J.

2015-12-01

Wind erosion is a key driver of global land degradation, with on- and off-site impacts on agricultural production, air quality, ecosystem services and climate. Measuring rates of wind erosion and dust emission across land use and land cover types is important for quantifying the impacts and identifying and testing practical management options. This process can be assisted by the application of predictive models, which can be a powerful tool for land management agencies. The Aeolian EROsion (AERO) model, a wind erosion and dust emission model interface provides access by non-expert land managers to a sophisticated wind erosion decision-support tool. AERO incorporates land surface processes and sediment transport equations from existing wind erosion models and was designed for application with available national long-term monitoring datasets (e.g. USDI BLM Assessment, Inventory and Monitoring, USDA NRCS Natural Resources Inventory) and monitoring protocols. Ongoing AERO model calibration and validation are supported by geographically diverse data on wind erosion rates and land surface conditions collected by the new National Wind Erosion Research Network. Here we present the new AERO interface, describe parameterization of the underpinning wind erosion model, and provide a summary of the model applications across agricultural lands and rangelands in the United States.

Determination of wind erosion intensity on heavy clay soils

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Jana Kozlovsky Dufková

2010-01-01

Full Text Available Wind erosion, common problem of light-textured soils, was determined on heavy clay soils in the foothills of Bílé Karpaty Mountains, Czech Republic. Soil erodibility by wind was determined from the Map of potential erodibility of soil by wind and from the calculation of potential and real soil loss by wind. All the determinations show underestimation of soil erodibility by wind on heavy clay soils, because methods that are used for this are based above all on the assessment of clay particles content and the presumption the more clay particles soil contains, the less vulnerable to wind erosion is. The potential erodibility of soil by wind is 0,09 t . ha−1 per year. The determined value does not exceed the tolerable soil loss limit 10 t . ha−1 per year for deep soils. The real average erodibility of soil by wind has the highest value 1,47 g . m−2 on November 30th, 2008. Other soil losses that do not exceed the tolerable soil loss limit 1,4 g . m−2, were determined on March 18th and 28th, 2008. Big difficulties come with the assessment of the erodibility of heavy clay soils in the areas, where soil erosion ve­ri­fia­bly exists, but it is not assessable by objective calculating methods. Evident necessity of new know­ledge concerning the determination of wind erosion intensity follows from the results.

Climate change and wind erosion by dust storms

International Nuclear Information System (INIS)

Wheaton, E.E.; Wittrock, V.

1991-01-01

Dust storms and their associated wind erosion are thought to be almost synonymous with drought. Dust storms have varying impacts including sandblasting and burying crops, wind erosion of soil, health effects and traffic accidents. A comparison of drought periods for southern Saskatchewan with dust storm frequencies for the period 1977-1988 revealed that the worst drought conditions coincided with the greatest April dust storm frequencies, with 1981 having the worst drought, and secondary spring droughts occurring in 1977, 1988, 1980 and 1982, and spring dust storm peaks occurring, in order of magnitude, in 1981, 1977, 1987, and 1982. An increase in atmospheric dust particles may lead to enhanced atmospheric subsidence and associated drought, and could be a positive feedback for drought intensity. Wind erosion potential may rise with rising temperature due to decreased vegetation cover, but the effect might be offset by rising precipitation

Soil erosion rates caused by wind and saltating sand stresses in a wind tunnel

International Nuclear Information System (INIS)

Ligotke, M.W.

1993-02-01

Wind erosion tests were performed in a wind tunnel in support of the development of long-term protective barriers to cap stabilized waste sites at the Hanford Site. Controlled wind and saltating sand erosive stresses were applied to physical models of barrier surface layers to simulate worst-case eolian erosive stresses. The goal of these tests was to provide information useful to the design and evaluation of the surface layer composition of an arid-region waste site barrier concept that incorporates a deep fine-soil reservoir. A surface layer composition is needed that will form an armor resistant to eolian erosion during periods of extreme dry climatic conditions, especially when such conditions result in the elimination or reduction of vegetation by water deprivation or wildfire. Because of the life span required of Hanford waste barriers, it is important that additional work follow these wind tunnel studies. A modeling effort is planned to aid the interpretation of test results with respect to the suitability of pea gravel to protect the finite-soil reservoir during long periods of climatic stress. It is additionally recommended that wind tunnel tests be continued and field data be obtained at prototype or actual barrier sites. Results wig contribute to barrier design efforts and provide confidence in the design of long-term waste site caps for and regions

Crater Mound Formation by Wind Erosion on Mars

Science.gov (United States)

Steele, L. J.; Kite, E. S.; Michaels, T. I.

2018-01-01

Most of Mars' ancient sedimentary rocks by volume are in wind-eroded sedimentary mounds within impact craters and canyons, but the connections between mound form and wind erosion are unclear. We perform mesoscale simulations of different crater and mound morphologies to understand the formation of sedimentary mounds. As crater depth increases, slope winds produce increased erosion near the base of the crater wall, forming mounds. Peak erosion rates occur when the crater depth is ˜2 km. Mound evolution depends on the size of the host crater. In smaller craters mounds preferentially erode at the top, becoming more squat, while in larger craters mounds become steeper sided. This agrees with observations where smaller craters tend to have proportionally shorter mounds and larger craters have mounds encircled by moats. If a large-scale sedimentary layer blankets a crater, then as the layer recedes across the crater it will erode more toward the edges of the crater, resulting in a crescent-shaped moat. When a 160 km diameter mound-hosting crater is subject to a prevailing wind, the surface wind stress is stronger on the leeward side than on the windward side. This results in the center of the mound appearing to "march upwind" over time and forming a "bat-wing" shape, as is observed for Mount Sharp in Gale crater.

An extreme wind erosion event of the fresh Eyjafjallajökull 2010 volcanic ash.

Science.gov (United States)

Arnalds, Olafur; Thorarinsdottir, Elin Fjola; Thorsson, Johann; Waldhauserova, Pavla Dagsson; Agustsdottir, Anna Maria

2013-01-01

Volcanic eruptions can generate widespread deposits of ash that are subsequently subjected to erosive forces which causes detrimental effects on ecosystems. We measured wind erosion of the freshly deposited Eyjafjallajökull ash at a field site the first summer after the 2010 eruption. Over 30 wind erosion events occurred (June-October) at wind speeds > 10 m s(-1) in each storm with gusts up to 38.7 m s(-1). Surface transport over one m wide transect (surface to 150 cm height) reached > 11,800 kg m(-1) during the most intense storm event with a rate of 1,440 kg m(-1) hr(-1) for about 6½ hrs. This storm is among the most extreme wind erosion events recorded on Earth. The Eyjafjallajökull wind erosion storms caused dust emissions extending several hundred km from the volcano affecting both air quality and ecosystems showing how wind erosion of freshly deposited ash prolongs impacts of volcanic eruptions.

Mechanics of interrill erosion with wind-driven rain

Science.gov (United States)

The vector physics of wind-driven rain (WDR) differs from that of wind-free rain, and the interrill soil detachment equations in the Water Erosion Prediction Project (WEPP) model were not originally developed to deal with this phenomenon. This article provides an evaluation of the performance of the...

A New Instrument for Testing Wind Erosion by Soil Surface Shape Change

International Nuclear Information System (INIS)

Hai, C.; Yuan, X.; Jiang, H.; Zhou, R.; Wang, J.; Liu, B.; Ye, Y.; Du, P.

2010-01-01

Wind erosion, a primary cause of soil degeneration, is a problem in arid and semiarid areas throughout the world. Many methods are available to study soil erosion, but there is no an effective method for making quantitative measurements in the field. To solve this problem, we have developed a new instrument that can measure the change in the shape of the soil surface, allowing quick quantification of wind erosion. In this paper, the construction and principle of the new instrument are described. Field experiments are carried out using the instrument, and the data are analyzed. The erosion depth is found to vary by 11% compared to the average for measurement areas ranging from 30 x 30 cm 2 to 10 x 10 cm 2 . The results show that the instrument is convenient and reliable for quantitatively measuring wind erosion in the field.

Using albedo to reform wind erosion modelling, mapping and monitoring

Science.gov (United States)

Chappell, Adrian; Webb, Nicholas P.

2016-12-01

Wind erosion and dust emission models are used to assess the impacts of dust on radiative forcing in the atmosphere, cloud formation, nutrient fertilisation and human health. The models are underpinned by a two-dimensional geometric property (lateral cover; L) used to characterise the three-dimensional aerodynamic roughness (sheltered area or wakes) of the Earth's surface and calibrate the momentum it extracts from the wind. We reveal a fundamental weakness in L and demonstrate that values are an order of magnitude too small and significant aerodynamic interactions between roughness elements and their sheltered areas have been omitted, particularly under sparse surface roughness. We describe a solution which develops published work to establish a relation between sheltered area and the proportion of shadow over a given area; the inverse of direct beam directional hemispherical reflectance (black sky albedo; BSA). We show direct relations between shadow and wind tunnel measurements and thereby provide direct calibrations of key aerodynamic properties. Estimation of the aerodynamic parameters from albedo enables wind erosion assessments over areas, across platforms from the field to airborne and readily available satellite data. Our new approach demonstrated redundancy in existing wind erosion models and thereby reduced model complexity and improved fidelity. We found that the use of albedo enabled an adequate description of aerodynamic sheltering to characterise fluid dynamics and predict sediment transport without the use of a drag partition scheme (Rt) or threshold friction velocity (u∗t). We applied the calibrations to produce global maps of aerodynamic properties which showed very similar spatial patterns to each other and confirmed the redundancy in the traditional parameters of wind erosion modelling. We evaluated temporal patterns of predicted horizontal mass flux at locations across Australia which revealed variation between land cover types that would not

Response of wind erosion dynamics to climate change and human activity in Inner Mongolia, China during 1990 to 2015.

Science.gov (United States)

Zhang, Haiyan; Fan, Jiangwen; Cao, Wei; Harris, Warwick; Li, Yuzhe; Chi, Wenfeng; Wang, Suizi

2018-10-15

Soil erosion caused by wind is a serious environmental problem that results in land degradation and threatens sustainable development. Accurately evaluating wind erosion dynamics is important for reducing the hazard of wind erosion. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. Based on meteorological, remote sensing and field observation data, we applied the Revised Wind Erosion Equation (RWEQ) to simulate wind erosion in Inner Mongolia, China from 1990 to 2015. We used the variable control method by input of the average climate conditions to calculate human-induced wind erosion. The difference between natural wind erosion and human-induced wind erosion was determined to assess the effect of climate change on wind erosion. The results showed that the wind erosion modulus had a remarkable decline with a slope of 52.23 t/km 2 /a from 1990 to 2015. During 26 years, the average wind erosion for Inner Mongolia amounted to 63.32 billion tons. Wind erosion showed an overall significant decline of 49.23% and the partial severer erosion hazard significantly increased by 7.11%. Of the significant regional decline, 40.72% was caused by climate changes, and 8.51% was attributed to ecological restoration programs. For the significant regional increases of wind erosion, 4.29% was attributed to climate changes and 2.82% to human activities, mainly overgrazing and land use/cover changes. During the study, the driving forces in Inner Mongolia of wind erosion dynamics differed spatially. Timely monitoring based on multi-source data and highlighting the importance of positive human activities by increasing vegetation coverage for deserts, reducing grazing pressure on grasslands, establishing forests as windbreaks and optimizing crop planting rotations of farmlands can all act to reduce and control wind erosion. Copyright © 2018 Elsevier B.V. All rights reserved.

Wind erosion in the Sahelian zone of Niger : processes, models, and control techniques

NARCIS (Netherlands)

Sterk, G.

1997-01-01

In the Sahelian zone of Niger, severe wind erosion occurs mainly in the first half of the rainy season (May - July), when violent winds preceding thunderstorms result in intense sediment transport. Quantification of this wind erosion is difficult due to a high degree of temporal and spatial

Effect of vegetation cover and transitions on regional wind erosion in drylands

NARCIS (Netherlands)

Youssef, I.F.

2012-01-01

Wind erosion is a critical environmental problem that threatens mainly the arid and semi-arid regions of our planet. Usually this problem is associated with desertification, poverty and other environmental and socioeconomic problems. Wind erosion causes the loss of fertile topsoil, and has a

Farmers' perceptions of erosion by wind and water in northern Burkina Faso

NARCIS (Netherlands)

Visser, S.M.; Leenders, J.K.; Leeuwis, M.

2003-01-01

Wind and water erosion are widespread phenomena throughout the Sahel, especially in the early rainy season, when high-intensity rainstorms are often preceded by severe windstorms. This paper describes the results of a survey on the farmers' perceptions of wind and water erosion processes and control

Estimation of wind erosion from construction of a railway in arid Northwest China

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Benli Liu

2017-06-01

Full Text Available A state-of-the-art wind erosion simulation model, the Wind Erosion Prediction System and the United States Environmental Protection Agency's AP 42 emission factors formula, were combined together to evaluate wind-blown dust emissions from various construction units from a railway construction project in the dry Gobi land in Northwest China. The influence of the climatic factors: temperature, precipitation, wind speed and direction, soil condition, protective measures, and construction disturbance were taken into account. Driven by daily and sub-daily climate data and using specific detailed management files, the process-based WEPS model was able to express the beginning, active, and ending phases of construction, as well as the degree of disturbance for the entire scope of a construction project. The Lanzhou-Xinjiang High-speed Railway was selected as a representative study because of the diversities of different climates, soil, and working schedule conditions that could be analyzed. Wind erosion from different working units included the building of roadbeds, bridges, plants, temporary houses, earth spoil and barrow pit areas, and vehicle transportation were calculated. The total wind erosion emissions, 7406 t, for the first construction area of section LXS-15 with a 14.877 km length was obtained for quantitative analysis. The method used is applicable for evaluating wind erosion from other complex surface disturbance projects.

Wind Erosion Processes and Control Techniques in the Sahelian Zone of Niger

NARCIS (Netherlands)

Sterk, G.; Stroosnijder, L.; Raats, P.A.C.

1999-01-01

Wind Erosion Processes and Control Techniques in the Sahelian Zone of Niger G. Sterk, L. Stroosnijder, and P.A.C. Raats Abstract The objective of this paper is to present the main results and conclusions from three years of field research on wind erosion processes and control techniques in the

Early-season wind erosion influenced by soil-incorporated green manure in the Pacific Northwest

Science.gov (United States)

Management strategies are sought to minimize wind erosion of irrigated agricultural soils along the Columbia River of the Inland Pacific Northwest, particularly during the early season (March-April) when high winds coincide with sowing of vegetable crops. Early-season wind erosion potential from soi...

Wind erosion potential of a winter wheat-summer fallow rotation after land application of biosolids

Science.gov (United States)

Pi, Huawei; Sharratt, Brenton; Schillinger, William F.; Bary, Andrew I.; Cogger, Craig G.

2018-06-01

Conservation tillage is a viable management strategy to control soil wind erosion, but other strategies such as land application of biosolids that enhance soil quality may also reduce wind erosion. No studies have determined the effects of biosolids on wind erosion. Wind erosion potential of a silt loam was assessed using a portable wind tunnel after applying synthetic and biosolids fertilizer to traditional (disk) and conservation (undercutter) tillage practices during the summer fallow phase of a winter wheat-summer fallow (WW-SF) rotation in 2015 and 2016 in east-central Washington. Soil loss ranged from 12 to 61% lower for undercutter than disk tillage, possibly due to retention of more biomass on the soil surface of the undercutter versus disk tillage treatment. In contrast, soil loss was similar to or lower for biosolids as compared with synthetic fertilizer treatment. Our results suggest that biosolids applications to agricultural lands will have minimal impact on wind erosion.

Mechanics of Interrill Erosion with Wind-Driven Rain (WDR)

Science.gov (United States)

This article provides an evaluation analysis for the performance of the interrill component of the Water Erosion Prediction Project (WEPP) model for Wind-Driven Rain (WDR) events. The interrill delivery rates (Di) were collected in the wind tunnel rainfall simulator facility of the International Cen...

Wind Erosion Induced Soil Degradation in Northern China: Status, Measures and Perspective

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Zhongling Guo

2014-12-01

Full Text Available Soil degradation is one of the most serious ecological problems in the world. In arid and semi-arid northern China, soil degradation predominantly arises from wind erosion. Trends in soil degradation caused by wind erosion in northern China frequently change with human activities and climatic change. To decrease soil loss by wind erosion and enhance local ecosystems, the Chinese government has been encouraging residents to reduce wind-induced soil degradation through a series of national policies and several ecological projects, such as the Natural Forest Protection Program, the National Action Program to Combat Desertification, the “Three Norths” Shelter Forest System, the Beijing-Tianjin Sand Source Control Engineering Project, and the Grain for Green Project. All these were implemented a number of decades ago, and have thus created many land management practices and control techniques across different landscapes. These measures include conservation tillage, windbreak networks, checkerboard barriers, the Non-Watering and Tube-Protecting Planting Technique, afforestation, grassland enclosures, etc. As a result, the aeolian degradation of land has been controlled in many regions of arid and semiarid northern China. However, the challenge of mitigating and further reversing soil degradation caused by wind erosion still remains.

WIND EROSION INTENSITY DETERMINATION USING SOIL PARTICLE CATCHER DEVICES

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Lenka Lackóová

2013-12-01

Full Text Available To analyze wind erosion events in the real terrain conditions, we proposed to construct a prototype of soil particle catcher devices to trap soil particles. With these devices we are able to measure the intensity of wind erosion at six different heights above the soil surface in one location or at three different heights in two places. It is possible to use them for six different places at the same time as well. We performed field measurements to determine the amount of soil particles transported by the wind between 26th – 31st March 2012. Each measuring took 60 minutes. After this time the soil particle catchers were emptied and further measurements carried out. At the beginning we selected two places for measurement (soil HPJ 16 and 37 at two heights, one above the other. Then we used two measuring systems 40 m apart at two sites (D2 and D4 and the soil captured at two heights (0, 1. The maximum weight of soil particles trapped in measuring system D2 at height (0 was 1242.7 g at a wind speed of 9.6 ms-1. At measurement height (1 the maximum weight was 72.7 g trapped at the same average hourly rate, but during different measurement events. The measuring system at D4 trapped the highest amount of soil at a wind speed of 8.9 ms-1 (1141.7 g at height (0 and at a speed of 9.3 ms-1 (22.3 g at height (1. During the measurements with the two basic measuring systems D4 and D2, we measured the wind erosion intensity together with soil particle catchers D1 and D3. D3 was placed between devices D4 and D2, D1 was 20 m ahead D2. Soil particle catchers were placed on the soil surface at height position (0. We measured increasing soil erosion downwind on four locations spaced at 20 m. The results show that with there is an increasing quantity of particles collected as the erosive surface length increases, due to the so-called snowball effect. We analyzed selected trapped soil samples in order to determine the size of the soil particles and their proportion

Wind erosion in semiarid landscapes: Predictive models and remote sensing methods for the influence of vegetation

Science.gov (United States)

Musick, H. Brad

1993-01-01

The objectives of this research are: to develop and test predictive relations for the quantitative influence of vegetation canopy structure on wind erosion of semiarid rangeland soils, and to develop remote sensing methods for measuring the canopy structural parameters that determine sheltering against wind erosion. The influence of canopy structure on wind erosion will be investigated by means of wind-tunnel and field experiments using structural variables identified by the wind-tunnel and field experiments using model roughness elements to simulate plant canopies. The canopy structural variables identified by the wind-tunnel and field experiments as important in determining vegetative sheltering against wind erosion will then be measured at a number of naturally vegetated field sites and compared with estimates of these variables derived from analysis of remotely sensed data.

Wind tunnel experiments on the effects of tillage ridge features on wind erosion horizontal fluxes

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M. Kardous

2005-11-01

Full Text Available In addition to the well-known soil factors which control wind erosion on flat, unridged surfaces, two specific processes affect the susceptibility of tillage ridged surfaces to wind erosion: ridge-induced roughness and ridge- trapping efficiency. In order to parameterize horizontal soil fluxes produced by wind over tillage ridges, eight-ridge configurations composed of sandy soil and exhibiting ridge heights to ridge spacing (RH/RS ratios ranging from 0.18 to 0.38 were experimented in a wind tunnel. These experiments are used to develop a parameterization of the horizontal fluxes over tillage ridged surfaces based only on the geometric characteristics of the ridges. Indeed, the key parameters controlling the horizontal flux, namely the friction velocity, threshold friction velocity and the adjustment coefficient, are derived through specific expressions, from ridge heights (RH and ridge spacing (RS. This parameterization was evaluated by comparing the results of the simulations to an additional experimental data set and to the data set obtained by Hagen and Armbrust (1992. In both cases, predicted and measured values are found to be in a satisfying agreement. This parameterization was used to evaluate the efficiency of ridges in reducing wind erosion. The results show that ridged surfaces, when compared to a loose, unridged soil surface, lead to an important reduction in the horizontal fluxes (exceeding 60%. Moreover, the effect of ridges in trapping particles contributes for more than 90% in the flux reduction while the ridge roughness effect is weak and decreases when the wind velocity increases.

Wind erosion potential of a winter wheat–summer fallow rotation after land application of biosolids

Science.gov (United States)

While land application of biosolids is recognized as a sustainable management practice for enhancing soil health, no studies have determined the effects of biosolids on soil wind erosion. Wind erosion potential of a silt loam was assessed using a portable wind tunnel after applying synthetic and bio...

Wind erosion control with scattered vegetation in the Sahelian zone of Burkina Faso

NARCIS (Netherlands)

Leenders, J.K.

2006-01-01

The Sahelian zone ofAfricais the region that is globally most subjected to land degradation, with wind erosion being the most important soil degradation process. By using control measures, the negative effects of wind erosion can be reduced. At present, adoption of

Wind driven erosion and the effects of particulate electrification

Science.gov (United States)

Merrison, J. P.; Bak, E.; Finster, K.; Gunnlaugsson, H. P.; Holstein-Rathlou, C.; Knak Jensen, S.; Nørnberg, P.; Rasmussen, K. R.

2012-09-01

Several related aspects of Aeolian activity are presently being studied in the laboratory, the most recent advances in this field will be presented. These include simulating wind driven erosion in the laboratory, quantifying erosion rates and the study of mineral change due to mechanical activation. Also advances in our understanding of the electrification of sand/dust particles is being made and how this phenomenon affects their behavior.

Soil deflation analyses from wind erosion events

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Lenka Lackóová

2015-09-01

Full Text Available There are various methods to assess soil erodibility for wind erosion. This paper focuses on aggregate analysis by a laser particle sizer ANALYSETTE 22 (FRITSCH GmbH, made to determine the size distribution of soil particles detached by wind (deflated particles. Ten soil samples, trapped along the same length of the erosion surface (150–155 m but at different wind speeds, were analysed. The soil was sampled from a flat, smooth area without vegetation cover or soil crust, not affected by the impact of windbreaks or other barriers, from a depth of maximum 2.5 cm. Prior to analysis the samples were prepared according to the relevant specifications. An experiment was also conducted using a device that enables characterisation of the vertical movement of the deflated material. The trapped samples showed no differences in particle size and the proportions of size fractions at different hourly average wind speeds. It was observed that most of particles travelling in saltation mode (size 50–500 μm – 58–70% – moved vertically up to 26 cm above the soil surface. At greater heights, particles moving in suspension mode (floating in the air; size < 100 μm accounted for up to 90% of the samples. This result suggests that the boundary between the two modes of the vertical movement of deflated soil particles lies at about 25 cm above the soil surface.

A history of wind erosion prediction models in the United States Department of Agriculture: The Wind Erosion Prediction System (WEPS)

Science.gov (United States)

Development of the Wind Erosion Prediction System (WEPS) was officially inaugurated in 1985 by United States Department of Agriculture-Agricultural Research Service (USDA-ARS) scientists in response to customer requests, particularly those coming from the USDA Soil Conservation Service (SCS), for im...

Wind tunnel experiments on the effects of tillage ridge features on wind erosion horizontal fluxes

Directory of Open Access Journals (Sweden)

M. Kardous

2005-11-01

Full Text Available In addition to the well-known soil factors which control wind erosion on flat, unridged surfaces, two specific processes affect the susceptibility of tillage ridged surfaces to wind erosion: ridge-induced roughness and ridge- trapping efficiency.

In order to parameterize horizontal soil fluxes produced by wind over tillage ridges, eight-ridge configurations composed of sandy soil and exhibiting ridge heights to ridge spacing (RH/RS ratios ranging from 0.18 to 0.38 were experimented in a wind tunnel. These experiments are used to develop a parameterization of the horizontal fluxes over tillage ridged surfaces based only on the geometric characteristics of the ridges. Indeed, the key parameters controlling the horizontal flux, namely the friction velocity, threshold friction velocity and the adjustment coefficient, are derived through specific expressions, from ridge heights (RH and ridge spacing (RS. This parameterization was evaluated by comparing the results of the simulations to an additional experimental data set and to the data set obtained by Hagen and Armbrust (1992. In both cases, predicted and measured values are found to be in a satisfying agreement.

This parameterization was used to evaluate the efficiency of ridges in reducing wind erosion. The results show that ridged surfaces, when compared to a loose, unridged soil surface, lead to an important reduction in the horizontal fluxes (exceeding 60%. Moreover, the effect of ridges in trapping particles contributes for more than 90% in the flux reduction while the ridge roughness effect is weak and decreases when the wind velocity increases.

The Dust Storm Index (DSI): A method for monitoring broadscale wind erosion using meteorological records

Science.gov (United States)

O'Loingsigh, T.; McTainsh, G. H.; Tews, E. K.; Strong, C. L.; Leys, J. F.; Shinkfield, P.; Tapper, N. J.

2014-03-01

Wind erosion of soils is a natural process that has shaped the semi-arid and arid landscapes for millennia. This paper describes the Dust Storm Index (DSI); a methodology for monitoring wind erosion using Australian Bureau of Meteorology (ABM) meteorological observational data since the mid-1960s (long-term), at continental scale. While the 46 year length of the DSI record is its greatest strength from a wind erosion monitoring perspective, there are a number of technical challenges to its use because when the World Meteorological Organisation (WMO) recording protocols were established the use of the data for wind erosion monitoring was never intended. Data recording and storage protocols are examined, including the effects of changes to the definition of how observers should interpret and record dust events. A method is described for selecting the 180 long-term ABM stations used in this study and the limitations of variable observation frequencies between stations are in part resolved. The rationale behind the DSI equation is explained and the examples of temporal and spatial data visualisation products presented include; a long term national wind erosion record (1965-2011), continental DSI maps, and maps of the erosion event types that are factored into the DSI equation. The DSI is tested against dust concentration data and found to provide an accurate representation of wind erosion activity. As the ABM observational records used here were collected according to WMO protocols, the DSI methodology could be used in all countries with WMO-compatible meteorological observation and recording systems.

Soil erosion rates from mixed soil and gravel surfaces in a wind tunnel: A preliminary report

International Nuclear Information System (INIS)

Ligotke, M.W.

1988-12-01

Tests of wind erosion were performed in a controlled-environment wind tunnel to support the development of natural-material protective barriers for long-term isolation of radioactive waste. Barrier performance standards currently being developed for internal and external barrier performance are expected to mandate a surface layer that is resistant to wind erosion. The purpose of this study was to initiate a series of tests to determine suitable soil and gravel mixtures for such a barrier and to test worst-case surface layer conditions under the influence of high wind speeds. Six mixed soil and gravel surfaces were prepared, weathered to represent natural wind-blown desert areas, and subjected to controlled wind erosion forces in a wind tunnel. The applied erosive forces, including surface shear forces, were characterized to provide a means of relating wind tunnel results with actual field conditions. Soil particle losses from the surfaces caused by suspension, saltation, and surface creep were monitored by aerosol sample probes and mass balance measurements. 23 refs., 22 figs., 3 tabs

Soil tillage and windbreak effects on millet and cowpea: I. Wind speed, evaporation, and wind erosion

International Nuclear Information System (INIS)

Banzhaf, J.; Leihner, D.E.; Buerkert, A.; Serafini, P.G.

1992-01-01

Deforestation, overgrazing, and declining soil regeneration periods have resulted in increased wind erosion problems in dry areas of the West African Sahel, but little is known about the bio-physical factors involved. This research was conducted to determine the effects of ridging and four different windbreak spacings on wind erosion, potential evaporation, and soil water reserves. A field trial was conducted from 1985 to 1987 on 12 ha of a Psammentic Paleustalf in Southern Niger. Millet, Pennisetum glaucum (L.), and cowpea, Vigna unguiculata (L.) Walp., were seeded in strips on flat and ridged soil. Windbreaks of savannah vegetation were spaced at 6, 20, 40, and 90 m. The effects of ridging on wind speed, evaporation, and wind erosion were small and mostly non-significant. However, average wind speed at 0.3 m above ground in the center of cowpea and millet strips was significantly reduced from 2.8 to 2.1 m s -1 as windbreak distances narrowed from 90 to 6 m. As a consequence, potential evaporation declined by 15% and the amount of windblown soil particles by 50% in ridged and by 70% in flat treatments. Despite reduced potential evaporation, average subsoil water reserves were 14 mm smaller in the 6- than in the 20-m windbreak spacing indicating excessive water extraction by the windbreak vegetation. Thus, establishing windbreaks with natural savannah vegetation may require a careful consideration of the agronomic benefits and costs to competing crops. 21 refs., 5 figs

Mapping wind erosion hazard in Australia using MODIS-derived ground cover, soil moisture and climate data

International Nuclear Information System (INIS)

Yang, X; Leys, J

2014-01-01

This paper describes spatial modeling methods to identify wind erosion hazard (WEH) areas across Australia using the recently available time-series products of satellite-derived ground cover, soil moisture and wind speed. We implemented the approach and data sets in a geographic information system to produce WEH maps for Australia at 500 m ground resolution on a monthly basis for the recent thirteen year period (2000–2012). These maps reveal the significant wind erosion hazard areas and their dynamic tendencies at paddock and regional scales. Dust measurements from the DustWatch network were used to validate the model and interpret the dust source areas. The modeled hazard areas and changes were compared with results from a rule-set approach and the Computational Environmental Management System (CEMSYS) model. The study demonstrates that the time series products of ground cover, soil moisture and wind speed can be jointly used to identify landscape erodibility and to map seasonal changes of wind erosion hazard across Australia. The time series wind erosion hazard maps provide detailed and useful information to assist in better targeting areas for investments and continuous monitoring, evaluation and reporting that will lead to reduced wind erosion and improved soil condition

Dryland Degradation by wind erosion and its control

NARCIS (Netherlands)

Sterk, G.; Riksen, M.; Goossens, D.

2001-01-01

Global population growth, is expected to impose an increasing pressure on agricultural production in the world's drylands, which cover approximately 41␘f the continental area. The land resources in drylands are severely threatened by soil degradation, with wind erosion being, one of the major

Wind born(e) landscapes: the role of wind erosion in agricultural land management and nature development

NARCIS (Netherlands)

Riksen, M.J.P.M.

2006-01-01

Wind has played an important role in the geological development of the north-western Europe. Various aeolian deposits such as inland dunes, river dunes, cover sands, drift sands and coastal dunes, form the base of large areas in our present landscape. The role of wind erosion in today's north-west

Implications of climate change on wind erosion of agricultural lands in the Columbia plateau

Directory of Open Access Journals (Sweden)

B.S. Sharratt

2015-12-01

Full Text Available Climate change may impact soil health and productivity as a result of accelerated or decelerated rates of erosion. Previous studies suggest a greater risk of wind erosion on arid and semi-arid lands due to loss of biomass under a future warmer climate. There have been no studies conducted to assess the impact of climate change on wind erosion in the Columbia Plateau of the Pacific Northwest United States where wind erosion of agricultural lands can cause exceedance of national air quality standards. The Wind Erosion Prediction System (WEPS was used to assess wind erosion and PM10 (particulate matter ≤10 µm in aerodynamic diameter emissions under a future climate projected by downscaling 18 Global Climate Models (GCM for a conservative emissions pathway. Wind erosion simulations were conducted at Lacrosse and Lind, WA and Moro, OR on a winter wheat-summer fallow (WW-SF rotation and at Lind on an additional winter wheat-camelina-summer fallow (WW-Cam-SF rotation. Each rotation was subject to conservation or conventional tillage practices for a baseline (1970–1999 and mid-21st century climate (2035–2064. A significant increase in temperature and nominal increases in precipitation were projected by an ensemble of climate models for the Columbia Plateau by the mid-21st century. Soil and PM10 losses were 25–84% lower for a mid-21st century climate, due in part to greater biomass production associated with CO2 fertilization and warmer temperatures. The reduction in soil and PM10 loss is projected to be more apparent for conservation tillage practices in the future. Soil and PM10 losses were greater from a WW-Cam-SF rotation than WW-SF rotation when conservation tillage practices were employed during the fallow phase of the rotations. Despite accounting for differences in the length of each rotation, annual soil and PM10 losses remained higher for the WW-Cam-SF rotation than the WW-SF rotation. Soil and PM10 losses were more variable across

Wind erosion on Deliblato (the largest European continental sandy terrain) studied using 210Pbex and 137Cs measurements

International Nuclear Information System (INIS)

Krmar, M.; Hansman, J.; Todorovic, N.; Mihailovic, A.; Vucinic-Vasic, M.; Savic, R.

2015-01-01

The objective of this paper is to estimate the difference in wind erosion between two extreme situations: sandy soil permanently covered by grass and the nearby frequently ploughed area highly susceptible to wind erosion. The spatial pattern of soil erosion rate was investigated using 137 Cs and 210 Pb ex tracing technique. The spatial pattern of erosion rate obtained within the studied area reveal influence of topography as well as direction of prevailing winds on mobilization and transport of the soil particles. (author)

Wind erosion of waste impoundments in arid climates and mitigation of dust pollution.

Science.gov (United States)

Blight, G E

2008-12-01

Wind can erode and disperse fine-grained material from an impoundment of mining, industrial or municipal waste that stands above the level of its surroundings. Such dust dispersion can be a serious nuisance as well as a health hazard to inhabitants and animals in nearby settlements. It can also degrade crops, making them less marketable, and pollute soil, surface water and ground water. Wind can seasonally erode waste impoundments in all types of climate, but the erosion intensifies and persists for more of each year as regional aridity increases. As clouds of dust are often observed billowing across the top surfaces of waste impoundments in dry windy weather, there is a common misconception that dust arises from erosion of the top surface of an impoundment, resulting in much effort and money being misspent on top treatments when in fact the sloped sides of the impoundments are the true source of blown dust. This paper offers a brief review of general waste impoundment wind erosion issues and then focuses in more detail on the mechanics of how wind erodes surfaces of waste impoundments. Recommendations are offered for mitigating the effects of wind-eroded dust.

Environmental risks associated to wind erosion in a metal mining area from SE Spain

International Nuclear Information System (INIS)

Garcia Fernandez, G.; Romero Diaz, A.

2009-01-01

Soils and mining wastes from the Mediterranean mining area placed in the Sierra Minera Mountains are highly enriched in heavy metals such as lead and zinc, but also other metals such as cadmium and arsenic. Wind erosion in this area could be considered extremely high and hazards associated to this eroded sediments seems to be high because the huge amount of metals present in this wastes. Therefore, combination of high erosion rates and high metal concentration in this mining waste, make those environmental risks can be considered high for the surrounding ecosystems, but also for public health of the nearby villages and towns. In order, to study these wind erosion processes over these mining materials, some experiments for the evaluation of the transportation of soil particles were carried out. Erosion rates in this realm is particularly important during spring months, when increased activity of the eastern winds brings intense soil dragging, with strong effects on the metals dispersion, including the massive removal of sediments. (Author) 16 refs.

Environmental risks associated to wind erosion in a metal mining area from SE Spain

Energy Technology Data Exchange (ETDEWEB)

Garcia Fernandez, G.; Romero Diaz, A.

2009-07-01

Soils and mining wastes from the Mediterranean mining area placed in the Sierra Minera Mountains are highly enriched in heavy metals such as lead and zinc, but also other metals such as cadmium and arsenic. Wind erosion in this area could be considered extremely high and hazards associated to this eroded sediments seems to be high because the huge amount of metals present in this wastes. Therefore, combination of high erosion rates and high metal concentration in this mining waste, make those environmental risks can be considered high for the surrounding ecosystems, but also for public health of the nearby villages and towns. In order, to study these wind erosion processes over these mining materials, some experiments for the evaluation of the transportation of soil particles were carried out. Erosion rates in this realm is particularly important during spring months, when increased activity of the eastern winds brings intense soil dragging, with strong effects on the metals dispersion, including the massive removal of sediments. (Author) 16 refs.

Literature review of models for estimating soil erosion and deposition from wind stresses on uranium-mill-tailings covers

International Nuclear Information System (INIS)

Bander, T.J.

1982-11-01

Pacific Northwest Laboratory (PNL) is investigating the use of a rock armoring blanket (riprap) to mitigate wind and water erosion of an earthen radon-suppression cover applied to uranium-mill tailings. The mechanics of wind erosion, as well as of soil deposition, are discussed in this report. Several wind erosion models are reviewed to determine if they can be used to estimate the erosion of soil from a mill-tailings cover. One model, developed by W.S. Chepil, contains the most-important factors that describe variables that influence wind erosion. Particular features of other models are also discussed, as well as the application of Chepil's model to a particular tailings pile. For this particular tailings pile, the estimated erosion was almost one inch per year for an unprotected tailings soil surface. Wide variability in the deposition velocity and lack of adequate deposition models preclude reliable estimates of the rate at which airborne particles are deposited

Literature review of models for estimating soil erosion and deposition from wind stresses on uranium-mill-tailings covers

Energy Technology Data Exchange (ETDEWEB)

Bander, T.J.

1982-11-01

Pacific Northwest Laboratory (PNL) is investigating the use of a rock armoring blanket (riprap) to mitigate wind and water erosion of an earthen radon-suppression cover applied to uranium-mill tailings. The mechanics of wind erosion, as well as of soil deposition, are discussed in this report. Several wind erosion models are reviewed to determine if they can be used to estimate the erosion of soil from a mill-tailings cover. One model, developed by W.S. Chepil, contains the most-important factors that describe variables that influence wind erosion. Particular features of other models are also discussed, as well as the application of Chepil's model to a particular tailings pile. For this particular tailings pile, the estimated erosion was almost one inch per year for an unprotected tailings soil surface. Wide variability in the deposition velocity and lack of adequate deposition models preclude reliable estimates of the rate at which airborne particles are deposited.

A history of wind erosion prediction models in the United States Department of Agriculture Prior to the Wind Erosion Prediction System

Science.gov (United States)

The Great Plains experienced an influx of settlers in the late 1850s to 1900. Periodic drought was hard on both settlers and the soil and caused severe wind erosion. The period known as the Dirty Thirties, 1931 to 1939, produced many severe windstorms, and the resulting dusty sky over Washington, D....

Crop production and economic loss due to wind erosion in hot arid ecosystem of India

Science.gov (United States)

Santra, Priyabrata; Moharana, P. C.; Kumar, Mahesh; Soni, M. L.; Pandey, C. B.; Chaudhari, S. K.; Sikka, A. K.

2017-10-01

Wind erosion is a severe land degradation process in hot arid western India and affects the agricultural production system. It affects crop yield directly by damaging the crops through abrasion, burial, dust deposition etc. and indirectly by reducing soil fertility. In this study, an attempt was made to quantify the indirect impact of wind erosion process on crop production loss and associated economic loss in hot arid ecosystem of India. It has been observed that soil loss due to wind erosion varies from minimum 1.3 t ha-1 to maximum 83.3 t ha-1 as per the severity. Yield loss due to wind erosion was found maximum for groundnut (Arachis hypogea) (5-331 kg ha-1 yr-1), whereas minimum for moth bean (Vigna aconitifolia) (1-93 kg ha-1 yr-1). For pearl millet (Pennisetum glaucum), which covers a major portion of arable lands in western Rajasthan, the yield loss was found 3-195 kg ha-1 yr-1. Economic loss was found higher for groundnut and clusterbean (Cyamopsis tetragonoloba) than rest crops, which are about

Wind erosion research at an uranium mill tailings site

International Nuclear Information System (INIS)

Sehmel, G.A.

1977-07-01

A uranium mill tailings pile at Grants, New Mexico, was selected for wind erosion research since the configuration provides flat area containing fine sand and made up of larger particles. The wind erosion experiment is discussed. Experimental equipment consists of meteorological instrumentation to automatically activate air samplers as a function of wind speed increments and direction, particle cascade impactors to measure airborne respirable concentrations as a function of particle size, inertial impaction devices to measure nonrespirable fluxes of airborne particles, a virtual particle cascade impactor to measure airborne concentrations of toxic trace elements, and soil depth gauges to measure changes in surface soil elevations as a function of time. Both radioactive particles as well as toxic trace element concentrations are measured. Radioactive particles are measured with both particle cascade impactors as well as high-volume air samplers. In contrast, toxic trace element airborne concentrations are measured only with a two-stage virtual particle cascade impactor. Fluxes of nonrespirable airborne particles are measured with inertial impaction devices. At particle cascade impactor sites, a rotating cyclone preseparator collects nonrespirable particles. In addition at all sites, fluxes of nonrespirable particles are measured using an open cavity inertial impaction device

Ice-Release and Erosion Resistant Materials for Wind Turbines

Science.gov (United States)

Zhang, Wei; Brinn, Cameron; Cook, Alex; Pascual-Marquez, Fernando

2017-11-01

Icing conditions may cause wind turbine generators to partially lose productivity or to be completely shut down to avoid structural damage. At present, commercially available technologies to mitigate this problem consist of expensive, energy hungry heating elements, which costs roughly 70,000 euro per medium size turbine. Conventional passive ice protection coating systems heavily rely on delicate surface structures and expensive materials to create water repellent superhydrophobic / low surface energy surfaces, which have been proven to be ineffective against ice accumulation. The lack of performance among conventional ice protection materials stems from a flaw in the approach to the problem: failure to recognize that water in its liquid form (WATER) and water in its solid form (ICE) are two different things. Something that works for WATER does not automatically work for ICE. Another reason is that many superhydrophobic materials are often reliant upon often fragile micro-structured surfaces to achieve their intended effects. This paper discusses a fundamentally different approach to the creation of a robust, low cost, durable, and multifunctional materials for ice release and erosion resistance. This National Science Foundation sponsored ice-release coating technology holds promise for protecting wind turbine blades and towers, thus potentially increasing reliability for power generation under icing conditions. Because of the vulnerability of wind turbine blades to ice buildup and erosion damages, wind farm facilities stand to reap considerable benefits.

Using Cesium-137 technique to study the characteristics of different aspect of soil erosion in the Wind-water Erosion Crisscross Region on Loess Plateau of China

International Nuclear Information System (INIS)

Li Mian; Li Zhanbin; Liu Puling; Yao Wenyi

2005-01-01

The most serious soil erosion on Loess Plateau exists in the Wind-water Erosion Crisscross Region. In the past 20 years, the types and intensity of soil erosion and its temporal and spatial distribution were studied, but studies on the difference of soil erosion between slope aspects and slope positions in this area have no report. However, it is very important to analyze and evaluate quantitatively the characteristics of different aspects and positions of soil loss for the prevention and treatment of soil erosion in this area. The spatial pattern of net soil loss on 4 downslope transects in four aspects (east, west, south and north) on a typical Mao (round loess mound) in Liudaogou catchment in Wind-water Erosion Crisscross Region was measured in 2000 using the resident cesium-137 deficit technique. The purposes of this investigation were undertaken to determine whether or not 137 Cs measurement would give a useful indication of the extent of soil loss and their characteristics from cultivated hillsides in different slope aspect and slope position in the study area. The results showed that the difference of soil erosion in different aspect was significant and the erosion rate was in this order: north>east>south>west. Compared with other areas, the difference of erosion rate between north hillside and south hillside was on the contrary, and the possible explanations could be the effect of wind erosion. Also, the percentage of wind erosion was estimated to be at least larger than 18% of total soil loss by comparing the difference of erosion amount in south hillside and north hillside. The erosion rates on different slope positions in all aspects were also different, the highest net soil loss occurred in the lower slope position, and the upper and middle slope positions were slight. The general trend of net soil loss on sloping surface was to increase in fluctuation with increasing downslope distance

Using Cesium-137 technique to study the characteristics of different aspect of soil erosion in the Wind-water Erosion Crisscross Region on Loess Plateau of China

Energy Technology Data Exchange (ETDEWEB)

Li Mian E-mail: hnli-mian@163.com; Li Zhanbin; Liu Puling; Yao Wenyi

2005-01-01

The most serious soil erosion on Loess Plateau exists in the Wind-water Erosion Crisscross Region. In the past 20 years, the types and intensity of soil erosion and its temporal and spatial distribution were studied, but studies on the difference of soil erosion between slope aspects and slope positions in this area have no report. However, it is very important to analyze and evaluate quantitatively the characteristics of different aspects and positions of soil loss for the prevention and treatment of soil erosion in this area. The spatial pattern of net soil loss on 4 downslope transects in four aspects (east, west, south and north) on a typical Mao (round loess mound) in Liudaogou catchment in Wind-water Erosion Crisscross Region was measured in 2000 using the resident cesium-137 deficit technique. The purposes of this investigation were undertaken to determine whether or not {sup 137}Cs measurement would give a useful indication of the extent of soil loss and their characteristics from cultivated hillsides in different slope aspect and slope position in the study area. The results showed that the difference of soil erosion in different aspect was significant and the erosion rate was in this order: north>east>south>west. Compared with other areas, the difference of erosion rate between north hillside and south hillside was on the contrary, and the possible explanations could be the effect of wind erosion. Also, the percentage of wind erosion was estimated to be at least larger than 18% of total soil loss by comparing the difference of erosion amount in south hillside and north hillside. The erosion rates on different slope positions in all aspects were also different, the highest net soil loss occurred in the lower slope position, and the upper and middle slope positions were slight. The general trend of net soil loss on sloping surface was to increase in fluctuation with increasing downslope distance.

Evaluation of chemical stabilizers and windscreens for wind erosion control of uranium mill tailings

International Nuclear Information System (INIS)

Elmore, M.R.; Hartley, J.N.

1984-08-01

Potential wind erosion of uranium mill tailings is a concern for the surface disposal of tailings at uranium mills. Wind-blown tailings may subsequently be redeposited on areas outside the impoundment. Pacific Northwest Laboratory (PNL) is investigating techniques for fugitive dust control at uranium mill tailings piles. Laboratory tests, including wind tunnel studies, were conducted to evaluate the relative effectiveness of 43 chemical stabilizers. Seventeen of the more promising stabilizers were applied to test plots on a uranium tailings pile at the American Nuclear Corporation-Gas Hills Project mill site in central Wyoming. The durabilities of these materials under actual site conditions were evaluated over time. In addition, field testing of commercially available windscreens was conducted. Test panels were constructed of eight different materials at the Wyoming test site to compare their durability. A second test site was established near PNL to evaluate the effectiveness of windscreens at reducing wind velocity, and thereby reduce the potential for wind erosion of mill tailings. Results of the laboratory land field tests of the chemical stabilizers and windscreens are presented, along with costs versus effectiveness of these techniques for control of wind erosion at mill tailings piles. 12 references, 4 figures, 6 tables

Leading edge erosion of coated wind turbine blades: Review of coating life models

NARCIS (Netherlands)

Slot, H.M.; Gelinck, E.R.M.; Rentrop, A.; van der Heide, Emile

2015-01-01

Erosion of the leading edge of wind turbine blades by droplet impingement wear, reduces blade aerodynamic efficiency and power output. Eventually, it compromises the integrity of blade surfaces. Elastomeric coatings are currently used for erosion resistance, yet the life of such coatings cannot be

Dust emission and soil loss due to anthropogenic activities by wind erosion simulations

Science.gov (United States)

Katra, Itzhak; Swet, Nitzan; Tanner, Smadar

2017-04-01

Wind erosion is major process of soil loss and air pollution by dust emission of clays, nutrients, and microorganisms. Many soils throughout the world are currently or potentially associated with dust emissions, especially in dryland zones. The research focuses on wind erosion in semi-arid soils (Northern Negev, Israel) that are subjected to increased human activities of urban development and agriculture. A boundary-layer wind tunnel has been used to study dust emission and soil loss by simulation and quantification of high-resolution wind processes. Field experiments were conducted in various surface types of dry loess soils. The experimental plots represent soils with long-term and short term influences of land uses such as agriculture (conventional and organic practices), grazing, and natural preserves. The wind tunnel was operated under various wind velocities that are above the threshold velocity of aeolian erosion. Total soil sediment and particulate matter (PM) fluxes were calculated. Topsoil samples from the experimental plots were analysed in the laboratory for physical and chemical characteristics including aggregation, organic matter, and high-resolution particle size distribution. The results showed variations in dust emission in response to surface types and winds to provide quantitative estimates of soil loss over time. Substantial loss of particulate matter that is < 10 micrometer in diameter, including clays and nutrients, was recorded in most experimental conditions. Integrative analyses of the topsoil properties and dust experiment highlight the significant implications for soil nutrient resources and management strategies as well as for PM loading to the atmosphere and air pollution.

Ecological site-based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands

Science.gov (United States)

Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.

2014-01-01

Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of

Ecological site‐based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands.

Science.gov (United States)

Webb, Nicholas P; Herrick, Jeffrey E; Duniway, Michael C

Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explored how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting, and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass–succulent states across the ecological sites at the plot scale (0.25 ha). We identified vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area could be effectively controlled when bare ground cover was 100 cm in length was less than ∼35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the

An index guiding temporal planting policies for wind erosion reduction

NARCIS (Netherlands)

Zhao, C.X.; Zheng, D.W.; Stigter, C.J.; He, W.Q.; Tuo, D.B.; Zhao, P.

2006-01-01

Vegetation cover has spatial as well as temporal characteristics, but the latter are often neglected. Temporal cover characteristics were explored to recommend planting policies for returning arable land into land better protected from serious wind erosion during late autumn, winter, and

Remote sensing of land use/cover changes and its effect on wind erosion potential in southern Iran

NARCIS (Netherlands)

Rezaei, Mahrooz; Sameni, Abdolmajid; Fallah Shamsi, Seyed Rashid; Bartholomeus, Harm

2016-01-01

Wind erosion is a complex process influenced by different factors. Most of these factors are stable over time, but land use/cover and land management practices are changing gradually. Therefore, this research investigates the impact of changing land use/cover and land management on wind erosion

Manufacturing issues which affect coating erosion performance in wind turbine blades

Science.gov (United States)

Cortés, E.; Sánchez, F.; Domenech, L.; Olivares, A.; Young, T. M.; O'Carroll, A.; Chinesta, F.

2017-10-01

Erosion damage, caused by repeated rain droplet impact on the leading edges of wind turbine blades, is a major cause for cost concern. Resin Infusion (RI) is used in wind energy blades where low weight and high mechanical performance materials are demanded. The surface coating plays a crucial role in the manufacturing and performance response. The Leading Edge coating is usually moulded, painted or sprayed onto the blade surface so adequate adhesion in the layers' characterization through the thickness is required for mechanical performance and durability reasons. In the current work, an investigation has been directed into the resulting rain erosion durability of the coating was undertaken through a combination of mass loss testing measurements with manufacturing processing parameter variations. The adhesion and erosion is affected by the shock wave caused by the collapsing water droplet on impact. The stress waves are transmitted to the substrate, so microestructural discontinuities in coating layers and interfaces play a key role on its degradation. Standard industrial systems are based on a multilayer system, with a high number of interfaces that tend to accelerate erosion by delamination. Analytical and numerical models are commonly used to relate lifetime prediction and to identify suitable coating and composite substrate combinations and their potential stress reduction on the interface. In this research, the input parameters for the appropriate definition of the Cohesive Zone Modelling (CZM) of the coating-substrate interface are outlined by means of Pull off testing and Peeling testing results. It allowed one to optimize manufacturing and coating process for blades into a knowledge-based guidance for leading edge coating material development. It was achieved by investigating the erosion degradation process using both numerical and laboratory techniques (Pull off, Peeling and Rain Erosion Testing in a whirling arm rain erosion test facility).

Wind erosion potential influenced by tillage in an irrigated potato-sweet corn rotation in the Columbia Basin

Science.gov (United States)

Wind erosion is a concern within the Columbia Basin of the Inland Pacific Northwest (PNW) United States due to the sandy texture of soils and small amount of residue retained on the soil surface after harvest of vegetable crops like potato. This study assessed potential wind erosion of an irrigated ...

Application of fuzzy logic approach for wind erosion hazard mapping in Laghouat region (Algeria) using remote sensing and GIS

Science.gov (United States)

Saadoud, Djouher; Hassani, Mohamed; Martin Peinado, Francisco José; Guettouche, Mohamed Saïd

2018-06-01

Wind erosion is one of the most serious environmental problems in Algeria that threatens human activities and socio-economic development. The main goal of this study is to apply a fuzzy logic approach to wind erosion sensitivity mapping in the Laghouat region, Algeria. Six causative factors, obtained by applying fuzzy membership functions to each used parameter, are considered: soil, vegetation cover, wind factor, soil dryness, land topography and land cover sensitivity. Different fuzzy operators (AND, OR, SUM, PRODUCT, and GAMMA) are applied to generate wind-erosion hazard map. Success rate curves reveal that the fuzzy gamma (γ) operator, with γ equal to 0.9, gives the best prediction accuracy with an area under curve of 85.2%. The resulting wind-erosion sensitivity map delineates the area into different zones of five relative sensitivity classes: very high, high, moderate, low and very low. The estimated result was verified by field measurements and the high statistically significant value of a chi-square test.

Wind Erosion Caused by Land Use Changes Significantly Reduces Ecosystem Carbon Storage and Carbon Sequestration Potentials in Grassland

Science.gov (United States)

Li, P.; Chi, Y. G.; Wang, J.; Liu, L.

2017-12-01

Wind erosion exerts a fundamental influence on the biotic and abiotic processes associated with ecosystem carbon (C) cycle. However, how wind erosion under different land use scenarios will affect ecosystem C balance and its capacity for future C sequestration are poorly quantified. Here, we established an experiment in a temperate steppe in Inner Mongolia, and simulated different intensity of land uses: control, 50% of aboveground vegetation removal (50R), 100% vegetation removal (100R) and tillage (TI). We monitored lateral and vertical carbon flux components and soil characteristics from 2013 to 2016. Our study reveals three key findings relating to the driving factors, the magnitude and consequence of wind erosion on ecosystem C balance: (1) Frequency of heavy wind exerts a fundamental control over the severity of soil erosion, and its interaction with precipitation and vegetation characteristics explained 69% variation in erosion intensity. (2) With increases in land use intensity, the lateral C flux induced by wind erosion increased rapidly, equivalent to 33%, 86%, 111% and 183% of the net ecosystem exchange of the control site under control, 50R, 100R and TI sites, respectively. (3) After three years' treatment, erosion induced decrease in fine fractions led to 31%, 43%, 85% of permanent loss of C sequestration potential in the surface 5cm soil for 50R, 100R and TI sites. Overall, our study demonstrates that lateral C flux associated with wind erosion is too large to be ignored. The loss of C-enriched fine particles not only reduces current ecosystem C content, but also results in irreversible loss of future soil C sequestration potential. The dynamic soil characteristics need be considered when projecting future ecosystem C balance in aeolian landscape. We also propose that to maintain the sustainability of grassland ecosystems, land managers should focus on implementing appropriate land use rather than rely on subsequent managements on degraded soils.

PM2.5 and PM10 Emission from agricultural soils by wind erosion

Science.gov (United States)

Soil tillage and wind erosion are a major source of particulate matter less than 2.5 and 10 µm (PM2.5 and PM10) emission from cultivated soil. Fifteen cultivated soils collected from 5 states were tested as crushed (<2.0 mm) and uncrushed (natural aggregation) at 8, 10, and 13 m s-1 wind velocity in...

Relative contributions of wind and water erosion to total soil loss and its effect on soil properties in sloping croplands of the Chinese Loess Plateau.

Science.gov (United States)

Tuo, Dengfeng; Xu, Mingxiang; Gao, Guangyao

2018-08-15

Wind and water erosion are two dominant types of erosion that lead to soil and nutrient losses. Wind and water erosion may occur simultaneously to varying extents in semi-arid regions. The contributions of wind and water erosion to total erosion and their effects on soil quality, however, remains elusive. We used cesium-137 ( 137 Cs) inventories to estimate the total soil erosion and used the Revised Universal Soil Loss Equation (RUSLE) to quantify water erosion in sloping croplands. Wind erosion was estimated from the subtraction of the two. We also used 137 Cs inventories to calculate total soil erosion and validate the relationships of the soil quality and erosion at different slope aspects and positions. The results showed that wind erosion (1460tkm -2 a -1 ) on northwest-facing slope was responsible for approximately 39.7% of the total soil loss, and water erosion (2216tkm -2 a -1 ) accounted for approximately 60.3%. The erosion rates were 58.8% higher on northwest- than on southeast-facing slopes. Northwest-facing slopes had lower soil organic carbon, total nitrogen, clay, and silt contents than southeast-facing slopes, and thus, the 137 Cs inventories were lower, and the total soil erosions were higher on the northwest-facing slopes. The variations in soil physicochemical properties were related to total soil erosion. The lowest 137 Cs inventories and nutrient contents were recorded at the upper positions on the northwest-facing slopes due to the successive occurrence of more severe wind and water erosion at the same site. The results indicated that wind and water could accelerate the spatial variability of erosion rate and soil properties and cause serious decreases in the nutrient contents in sloping fields. Our research could help researchers develop soil strategies to reduce soil erosion according to the dominant erosion type when it occurs in a hilly agricultural area. Copyright © 2018 Elsevier B.V. All rights reserved.

The combined effect of wind and rain on interrill erosion processes

International Nuclear Information System (INIS)

Erpul, G.; Gabriels, D.; Norton, L.D.

2004-01-01

flow-driven process begins to transport the detached soil particles. This is different from the approach of recent interrill erosion models that soil detached by the rain splash will be subsequently transported by overland flow. The results of the study showed that, when compared to the contribution of the flow-driven transport, the contribution of the rain splash transport was significant to the extent that it should not be neglected in accurately predicting water erosion from interrill areas under wind-driven rains

[Estimation of the effect derived from wind erosion of soil and dust emission in Tianjin suburbs on the central district based on WEPS model].

Science.gov (United States)

Chen, Li; Han, Ting-Ting; Li, Tao; Ji, Ya-Qin; Bai, Zhi-Peng; Wang, Bin

2012-07-01

Due to the lack of a prediction model for current wind erosion in China and the slow development for such models, this study aims to predict the wind erosion of soil and the dust emission and develop a prediction model for wind erosion in Tianjin by investigating the structure, parameter systems and the relationships among the parameter systems of the prediction models for wind erosion in typical areas, using the U.S. wind erosion prediction system (WEPS) as reference. Based on the remote sensing technique and the test data, a parameter system was established for the prediction model of wind erosion and dust emission, and a model was developed that was suitable for the prediction of wind erosion and dust emission in Tianjin. Tianjin was divided into 11 080 blocks with a resolution of 1 x 1 km2, among which 7 778 dust emitting blocks were selected. The parameters of the blocks were localized, including longitude, latitude, elevation and direction, etc.. The database files of blocks were localized, including wind file, climate file, soil file and management file. The weps. run file was edited. Based on Microsoft Visualstudio 2008, secondary development was done using C + + language, and the dust fluxes of 7 778 blocks were estimated, including creep and saltation fluxes, suspension fluxes and PM10 fluxes. Based on the parameters of wind tunnel experiments in Inner Mongolia, the soil measurement data and climate data in suburbs of Tianjin, the wind erosion module, wind erosion fluxes, dust emission release modulus and dust release fluxes were calculated for the four seasons and the whole year in suburbs of Tianjin. In 2009, the total creep and saltation fluxes, suspension fluxes and PM10 fluxes in the suburbs of Tianjin were 2.54 x 10(6) t, 1.25 x 10(7) t and 9.04 x 10(5) t, respectively, among which, the parts pointing to the central district were 5.61 x 10(5) t, 2.89 x 10(6) t and 2.03 x 10(5) t, respectively.

The National Wind Erosion Research Network: Building a standardized long-term data resource for aeolian research, modeling and land management

Science.gov (United States)

Webb, Nicholas P.; Herrick, Jeffrey E.; Van Zee, Justin W; Courtright, Ericha M; Hugenholtz, Ted M; Zobeck, Ted M; Okin, Gregory S.; Barchyn, Thomas E; Billings, Benjamin J; Boyd, Robert A.; Clingan, Scott D; Cooper, Brad F; Duniway, Michael C.; Derner, Justin D.; Fox, Fred A; Havstad, Kris M.; Heilman, Philip; LaPlante, Valerie; Ludwig, Noel A; Metz, Loretta J; Nearing, Mark A; Norfleet, M Lee; Pierson, Frederick B; Sanderson, Matt A; Sharrat, Brenton S; Steiner, Jean L; Tatarko, John; Tedela, Negussie H; Todelo, David; Unnasch, Robert S; Van Pelt, R Scott; Wagner, Larry

2016-01-01

The National Wind Erosion Research Network was established in 2014 as a collaborative effort led by the United States Department of Agriculture’s Agricultural Research Service and Natural Resources Conservation Service, and the United States Department of the Interior’s Bureau of Land Management, to address the need for a long-term research program to meet critical challenges in wind erosion research and management in the United States. The Network has three aims: (1) provide data to support understanding of basic aeolian processes across land use types, land cover types, and management practices, (2) support development and application of models to assess wind erosion and dust emission and their impacts on human and environmental systems, and (3) encourage collaboration among the aeolian research community and resource managers for the transfer of wind erosion technologies. The Network currently consists of thirteen intensively instrumented sites providing measurements of aeolian sediment transport rates, meteorological conditions, and soil and vegetation properties that influence wind erosion. Network sites are located across rangelands, croplands, and deserts of the western US. In support of Network activities, http://winderosionnetwork.org was developed as a portal for information about the Network, providing site descriptions, measurement protocols, and data visualization tools to facilitate collaboration with scientists and managers interested in the Network and accessing Network products. The Network provides a mechanism for engaging national and international partners in a wind erosion research program that addresses the need for improved understanding and prediction of aeolian processes across complex and diverse land use types and management practices.

Soil drying and wind erosion as affected by different types of shelterbelts planted in the desert region of western Rajasthan, India

Energy Technology Data Exchange (ETDEWEB)

Gupta, J.P.; Rao, G.G.S.N.; Gupta, G.N.; Rao, B.V.R.

1983-03-01

Studies on the effects of 8-year-old shelterbelt plantations indicate a general reduction in wind velocity, wind erosion and evaporative loss of moisture from fields protected with Prosopis juliflora, Cassia siamea and Acacia tortilis. Cassia siamea shelterbelts are the most effective in checking wind erosion and delaying drying of the soil. (Refs. 13).

Interactive effects of moss-dominated crusts and Artemisia ordosica on wind erosion and soil moisture in Mu Us sandland, China.

Science.gov (United States)

Yang, Yongsheng; Bu, Chongfeng; Mu, Xingmin; Shao, Hongbo; Zhang, Kankan

2014-01-01

To better understand the effects of biological soil crusts (BSCs) on soil moisture and wind erosion and study the necessity and feasibility of disturbance of BSCs in the Mu Us sandland, the effects of four treatments, including moss-dominated crusts alone, Artemisia ordosica alone, bare sand, and Artemisia ordosica combined with moss-dominated crusts, on rainwater infiltration, soil moisture, and annual wind erosion were observed. The major results are as follows. (1) The development of moss-dominated crusts exacerbated soil moisture consumption and had negative effects on soil moisture in the Mu Us sandland. (2) Moss-dominated crusts significantly increased soil resistance to wind erosion, and when combined with Artemisia ordosica, this effect became more significant. The contribution of moss-dominated crusts under Artemisia ordosica was significantly lower than that of moss-dominated crusts alone in sites where vegetative coverage > 50%. (3) Finally, an appropriate disturbance of moss-dominated crusts in the rainy season in sites with high vegetative coverage improved soil water environment and vegetation succession, but disturbance in sites with little or no vegetative cover should be prohibited to avoid the exacerbation of wind erosion.

Sonic anemometry and sediment traps to evaluate the effectiveness of windbreaks in preventing wind erosion

Directory of Open Access Journals (Sweden)

Alejandro López

Full Text Available ABSTRACT The present work analyzes the effectiveness of windbreaks against wind erosion through the study of streamline patterns and turbulent flow by means of sonic anemometry and sediment traps. To this end, windbreaks composed of plastic meshes (7.5 m long and 0.7 m tall were used. Windbreaks are a good means to reduce wind erosion, as they produce a positive effect on the characteristics of air currents that are related to wind erosion processes. Due to their ease of installation and dismantling, plastic meshes are widely used in areas where they are not required permanently. In our study, the use of a mesh of 13 × 30 threads cm−2 and 39 % porosity resulted in an average reduction of 85 % in face velocity at a height of 0.4 m and a distance of 1 m from the windbreak. The turbulence intensity i increased behind the windbreak because the reduction of mean of air speed on the leeside caused by the flow of air through the windbreak. Fluctuation levels, however, remained stable. The mean values of turbulence kinetic energy k decreased by 65 % to 86 % at a distance of 1 m from the windbreak and at a height of 0.4 m. The windbreak reduces erosion and sediment transportation 2 m downwind (2.9 times the windbreak height. Nevertheless, sediment transportation was not reduced at a height of 1.0 m and the effect of the windbreak was not observed at a distance of 6 m downwind (8.6 m times the windbreak height.

Development and validation of a method to estimate the potential wind erosion risk in Germany

Science.gov (United States)

Funk, Roger; Deumlich, Detlef; Völker, Lidia

2017-04-01

The introduction of the Cross Compliance (CC) regulations for soil protection resulted in the demand for the classification of the the wind erosion risk on agricultural areas in Germany nationwide. A spatial highly resolved method was needed based on uniform data sets and validation principles, which provides a fair and equivalent procedure for all affected farmers. A GIS-procedure was developed, which derives the site specific wind erosion risk from the main influencing factors: soil texture, wind velocity, wind direction and landscape structure following the German standard DIN 19706. The procedure enables different approaches in the Federal States and comparable classification results. Here, we present the approach of the Federal State of Brandenburg. In the first step a complete soil data map was composed in a grid size of 10 x 10 m. Data were taken from 1.) the Soil quality Appraisal (scale 1:10.000), 2.) the Medium-scale Soil Mapping (MMK, 1:25.000), 3.) extrapolating the MMK, 4.) new Soil quality Appraisal (new areas after coal-mining). Based on the texture and carbon content the wind erosion susceptibility was divided in 6 classes. This map was combined with data of the annual average wind velocity resulting in an increase of the risk classes for wind velocities > 5 ms-1 and a decrease for structure is regarded by allocating a height to each landscape element, corresponding to the described features in the digital "Biotope and Land Use Map". The "hill shade" procedure of ArcGIS was used to set virtual shadows behind the landscape elements for eight directions. The relative frequency of wind from each direction was used as a weighting factor and multiplied with the numerical values of the shadowed cells. Depending on the distance to the landscape element the shadowing effect was combined with the risk classes. The results show that the wind erosion risk is obviously reduced by integrating landscape structures into the risk assessment. After the renewed

Retrospection of recent 30-year changes in the process of soil wind erosion in the Luanhe River Source Area of North China using Cesium-137

Energy Technology Data Exchange (ETDEWEB)

Chen Zhifan [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xin Jie Kou Wai St., Beijing 100875 (China) and College of Environment and Planning, Henan University, Kaifeng 475001 (China)], E-mail: chenzhf0604@163.com; Zhao Ye [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xin Jie Kou Wai St., Beijing 100875 (China)], E-mail: zhaoye@bnu.edu.cn; Qiao Jiejuan [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xin Jie Kou Wai St., Beijing 100875 (China); Zhang Qing [National Institute for Radiological Protection, Chinese Center for Disease Control and Protection, Beijing 100088 (China); Zhu Yuen [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xin Jie Kou Wai St., Beijing 100875 (China); Xu Cuihua [National Institute for Radiological Protection, Chinese Center for Disease Control and Protection, Beijing 100088 (China)

2009-10-15

The Luanhe River Source Area belongs to typical semi-arid, agro-pastoral ecotone of North China. It is very important for the prevention and treatment of soil erosion in North China to analyze and evaluate quantitatively the recent 30-year changes in the process of soil wind erosion in this area. Based on long field observations, soil samples from different depths in a representative wind-deposited soil profile in the Luanhe River Source Area were collected. Then the {sup 137}Cs activity of soil samples from different depths in the soil profile was determined using a GEM series HPGe (high-purity germanium) coaxial detector system (ADCAM-100), and their soil properties, such as the soil particle fraction and so on, were analyzed. According to the detected {sup 137}Cs activity of different depths, a continuous time sequence of the wind-deposited soil profile in the study area was established. Furthermore, through assumption on a soil relative wind erosion intensity index (SWEI), recent 30-year changes in the process of soil wind erosion in the Luanhe River Source Area were retrospected . The analysis results revealed that weaker soil wind erosion occurred in the study area from the 1970s to the early 1980s and from the late 1980s to the mid to late 1990s. Conversely, intense periods of soil wind erosion occurred in the mid-1980s and from the late 1990s to 2002.

Retrospection of recent 30-year changes in the process of soil wind erosion in the Luanhe River Source Area of North China using Cesium-137

International Nuclear Information System (INIS)

Chen Zhifan; Zhao Ye; Qiao Jiejuan; Zhang Qing; Zhu Yuen; Xu Cuihua

2009-01-01

The Luanhe River Source Area belongs to typical semi-arid, agro-pastoral ecotone of North China. It is very important for the prevention and treatment of soil erosion in North China to analyze and evaluate quantitatively the recent 30-year changes in the process of soil wind erosion in this area. Based on long field observations, soil samples from different depths in a representative wind-deposited soil profile in the Luanhe River Source Area were collected. Then the 137 Cs activity of soil samples from different depths in the soil profile was determined using a GEM series HPGe (high-purity germanium) coaxial detector system (ADCAM-100), and their soil properties, such as the soil particle fraction and so on, were analyzed. According to the detected 137 Cs activity of different depths, a continuous time sequence of the wind-deposited soil profile in the study area was established. Furthermore, through assumption on a soil relative wind erosion intensity index (SWEI), recent 30-year changes in the process of soil wind erosion in the Luanhe River Source Area were retrospected . The analysis results revealed that weaker soil wind erosion occurred in the study area from the 1970s to the early 1980s and from the late 1980s to the mid to late 1990s. Conversely, intense periods of soil wind erosion occurred in the mid-1980s and from the late 1990s to 2002.

A universal meteorological method to identify potential risk of wind erosion on heavy-textured soils

Directory of Open Access Journals (Sweden)

Středová Hana

2015-06-01

Full Text Available The climate of Central Europe, mainly winter seasons with no snow cover at lower altitudes and a spring drought as well, might cause erosion events on heavy-textured soils. The aim of this paper is to define a universal method to identify the potential risk of wind erosion on heavy-textured soils. The categorization of potential wind erosion risk due to meteorological conditions is based on: (i an evaluation of the number of freeze-thaw episodes forming bare soil surfaces during the cold period of year; and (ii, an evaluation of the number of days with wet soil surfaces during the cold period of year. In the period 2001–2012 (from November to March, episodes with temperature changes from positive to negative and vice versa (thaw-freeze and freeze-thaw cycles and the effects of wet soil surfaces in connection with aggregate disintegration, are identified. The data are spatially interpolated by GIS tools for areas in the Czech Republic with heavy-textured soils. Blending critical categories is used to locate potential risks. The level of risk is divided into six classes. Those areas identified as potentially most vulnerable are the same localities where the highest number of erosive episodes on heavy-textured soils was documented.

Soil wind erosion in ecological olive trees in the Tabernas desert (southeastern Spain): a wind tunnel experiment

Science.gov (United States)

Asensio, Carlos; Lozano, Francisco Javier; Gallardo, Pedro; Giménez, Antonio

2016-08-01

Wind erosion is a key component of the soil degradation processes. The purpose of this study is to find out the influence of material loss from wind on soil properties for different soil types and changes in soil properties in olive groves when they are tilled. The study area is located in the north of the Tabernas Desert, in the province of Almería, southeastern Spain. It is one of the driest areas in Europe, with a semiarid thermo-Mediterranean type of climate. We used a new wind tunnel model over three different soil types (olive-cropped Calcisol, Cambisol and Luvisol) and studied micro-plot losses and deposits detected by an integrated laser scanner. We also studied the image processing possibilities for examining the particles attached to collector plates located at the end of the tunnel to determine their characteristics and whether they were applicable to the setup. Samples collected in the traps at the end of the tunnel were analyzed. We paid special attention to the influence of organic carbon, carbonate and clay contents because of their special impact on soil crusting and the wind-erodible fraction. A principal components analysis (PCA) was carried out to find any relations on generated dust properties and the intensity and behavior of those relationships. Component 1 separated data with high N and OC contents from samples high in fine silt, CO3= and available K content. Component 2 separated data with high coarse silt and clay contents from data with high fine sand content. Component 3 was an indicator of available P2O5 content. Analysis of variance (ANOVA) was carried out to analyze the effect of soil type and sampling height on different properties of trapped dust. Calculations based on tunnel data showed overestimation of erosion in soil types and calculation of the fraction of soil erodible by wind done by other authors for Spanish soils. As the highest loss was found in Cambisols, mainly due to the effect on soil crusting and the wind

Evaluation of the 137Cs technique for estimating wind erosion losses for some sandy Western Australian soils

International Nuclear Information System (INIS)

Harper, R.J.; Gilkes, R.J.

1994-01-01

The utility of the caesium-137 technique, for estimating the effects of wind erosion, was evaluated on the soils of a semi-arid agricultural area near Jerramungup, Western Australia. The past incidence of wind erosion was estimated from field observations of soil profile morphology and an existing remote sensing study. Erosion was limited to sandy surfaced soils (0-4% clay), with a highly significant difference (P 137 Cs values between eroded and non-eroded sandy soils, with mean values of 243±17 and 386±13 Bq m -2 respectively. Non-eroded soils, with larger clay contents, had a mean 137 Cs content of 421±26 Bq m -2 , however, due to considerable variation between replicate samples, this value was not significantly different from that of the non-eroded sands. Hence, although the technique discriminates between eroded and non-eroded areas, the large variation in 137 Cs values means that from 27 to 96 replicate samples are required to provide statistically valid estimates of 137 Cs loss. The occurrence of around 18% of the total 137 Cs between 10 and 20 cm depth in these soils, despite cultivation being confined to the surface 9 cm, suggests that leaching of 137 Cs occurs in the sandy soils, although there was no relationship between clay content and 137 Cs value for either eroded or non-eroded soils. In a multiple linear regression, organic carbon content and the mean grain size of the eroded soils explained 35% of the variation in 137 Cs content. This relationship suggests that both organic carbon and 137 Cs are removed by erosion, with erosion being more prevalent on soils with a finer sand fraction. Clay and silt contents do not vary with depth in the near-surface horizons of the eroded sandy soils, hence it is likely that wind erosion strips the entire surface horizon with its 137 Cs content, rather than selectively winnowing fine material. 71 refs., 6 tabs., 2 fig

Climatological changing effects on wind, precipitation and erosion: Large, meso and small scale analysis

International Nuclear Information System (INIS)

Aslan, Z.

2004-01-01

The Fourier transformation analysis for monthly average values of meteorological parameters has been considered, and amplitudes, phase angles have been calculated by using ground measurements in Turkey. The first order harmonics of meteorological parameters show large scale effects, while higher order harmonics show the effects of small scale fluctuations. The variations of first through sixth order harmonic amplitudes and phases provide a useful means of understanding the large and local scale effects on meteorological parameters. The phase angle can be used to determine the time of year the maximum or minimum of a given harmonic occurs. The analysis helps us to distinguish different pressure, relative humidity, temperature, precipitation and wind speed regimes and transition regions. Local and large scale phenomenon and some unusual seasonal patterns are also defined near Keban Dam and the irrigation area. Analysis of precipitation based on long term data shows that semi-annual fluctuations are predominant in the study area. Similarly, pressure variations are mostly influenced by semi-annual fluctuations. Temperature and humidity variations are mostly influenced by meso and micro scale fluctuations. Many large and meso scale climate change simulations for the 21st century are based on concentration of green house gases. A better understanding of these effects on soil erosion is necessary to determine social, economic and other impacts of erosion. The second part of this study covers the time series analysis of precipitation, rainfall erosivity and wind erosion at the Marmara Region. Rainfall and runoff erosivity factors are defined by considering the results of field measurements at 10 stations. Climatological changing effects on rainfall erosion have been determined by monitoring meteorological variables. In the previous studies, Fournier Index is defined to estimate the rainfall erosivity for the study area. The Fournier Index or in other words a climatic index

Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites

Science.gov (United States)

Chojnacki, Matthew; Banks, Maria; Urso, Anna

2018-01-01

Aeolian processes have likely been the predominant geomorphic agent for most of Mars’ history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low. PMID:29568719

Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites

Science.gov (United States)

Chojnacki, Matthew; Banks, Maria; Urso, Anna

2018-02-01

Aeolian processes have likely been the predominant geomorphic agent for most of Mars' history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low.

Soil Erosion. LC Science Tracer Bullet.

Science.gov (United States)

Buydos, John F., Comp.

Soil erosion is the detachment and movement of topsoil or soil material from the upper part of the soil profile. It may occur in the form of rill, gully, sheet, or wind erosion. Agents of erosion may be water, wind, glacial ice, agricultural implements, machinery, and animals. Soil conservation measures require a thorough understanding of the…

Separation of dry and wet periods from regular weather station data for the analysis of wind erosion risk

DEFF Research Database (Denmark)

Naeini, Mohammadali Saremi; Fister, Wolfgang; Heckrath, Goswin Johann

importance, soil moisture content is often ignored in the analysis of wind data for wind erosion studies. The main reason most probably being the lack of soil moisture sensors in conventional climate stations. Soil moisture at a given point in time is determined by rain (e.g. rainfall amount, duration......), climate (e.g. air temperature, solar radiation, evaporation) and soil (e.g. infiltration rate, adhesion). The purpose of this study is to overcome the lack of soil moisture data for wind erosion risk assessment by developing a method to estimate the soil wetness based on easy available weather data......, such as daily precipitation, hourly/sub hourly ambient air temperature and hourly/sub hourly relative humidity. This new method was used to identify periods of wet and dry soil moisture conditions of a time series from 20 weather stations in Denmark. The length of the time series varied between 8 to 37 years...

Drawing a representative sample from the NCSS soil database: Building blocks for the national wind erosion network

Science.gov (United States)

Developing national wind erosion models for the continental United States requires a comprehensive spatial representation of continuous soil particle size distributions (PSD) for model input. While the current coverage of soil survey is nearly complete, the most detailed particle size classes have c...

A simple method to downscale daily wind statistics to hourly wind data

OpenAIRE

Guo, Zhongling

2013-01-01

Wind is the principal driver in the wind erosion models. The hourly wind speed data were generally required for precisely wind erosion modeling. In this study, a simple method to generate hourly wind speed data from daily wind statistics (daily average and maximum wind speeds together or daily average wind speed only) was established. A typical windy location with 3285 days (9 years) measured hourly wind speed data were used to validate the downscaling method. The results showed that the over...

WECC Variable Generation Planning Reference Book: Appendices

Energy Technology Data Exchange (ETDEWEB)

Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

2013-05-13

The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

Assessing the vegetation canopy influences on wind flow using wind ...

Indian Academy of Sciences (India)

Artificial plastic vegetations with different porosity and canopy shape were introduced as ... Wind erosion is the Aeolian process by which soil particles are detached from ..... the stabilizing role of vegetation on wind erosion. And therefore, for ...

Appendiceal hemorrhage – An uncommon cause of lower gastrointestinal bleeding

Directory of Open Access Journals (Sweden)

Ching-Chung Chiang

2011-06-01

Full Text Available Lower gastrointestinal bleeding is a common disease among elderly patients. The common sources of lower gastrointestinal bleeding include vascular disease, Crohn’s disease, neoplasms, inflammatory bowel disease, hemorrhoids, and ischemic colitis. Lower gastrointestinal bleeding arising from the appendix is an extremely rare condition. We report a case of appendiceal hemorrhage in a young male. Diagnosis was made by multidetector computerized tomography during survey for hematochezia. The patient recovered well after appendectomy. The histological finding revealed focal erosion of appendix mucosa with bleeding.

75 FR 75961 - Notice of Implementation of the Wind Erosion Prediction System for Soil Erodibility System...

Science.gov (United States)

2010-12-07

... implementation of the WEPS system does not affect the Highly Erodible Map Unit List contained in the NRCS Field Office Technical Guide as of January 1, 1990. This 1990 list will continue to be used for all erodibility... plant damage, and predict PM-10 emissions when wind speeds exceed the erosion threshold. The WEPS model...

Changes in wind erosion over a 25-year restoration chronosequence on the south edge of the Tengger Desert, China: implications for preventing desertification.

Science.gov (United States)

Ma, Quanlin; Fehmi, Jeffrey S; Zhang, Dekui; Fan, Baoli; Chen, Fang

2017-08-23

Wind erosion is a primary cause of desertification as well as being a serious ecological problem in arid and semi-arid areas across the world. To determine mechanisms for restoring desertified lands, an unrestored shifting sand dune and three formerly shifting sand dunes (desertified lands) that had been enclosed and afforested for 5, 15, and 25 years were selected for evaluation on the south edge of the Tengger Desert, China. Based on sampling heights between 0.2 and 3 m, the critical threshold average wind speed was 6.5 m s -1 at 2 m where the sand transport rate was reduced from 285.9 kg m -2  h -1 on the unrestored dunes to 9.1 and 1.8 kg m -2  h -1 on the sites afforested and enclosed for 5 and 15 years, respectively. The percentage of wind eroded area was reduced from 99.9% on the unrestored dune to 94.5, 9.0, and 0.5% on the sites afforested and enclosed for 5, 15, and 25 years, respectively. Wind erosion was effectively reduced after 15 years. Although there were different driving factors for wind erosion mitigation on the different restoration stages, an increase in the vegetation cover, surface roughness, soil shear strength, soil clay content, organic matter, and reduction in the near-surface wind speed were the primary variables associated with the restoration chronosequence. We conclude that reducing the wind speed and developing a biological crust through vegetation restoration were the critical components for restoration of desertified land.

Contributions of solar-wind induced potential sputtering to the lunar surface erosion rate and it's exosphere

Science.gov (United States)

Alnussirat, S. T.; Barghouty, A. F.; Edmunson, J. E.; Sabra, M. S.; Rickman, D. L.

2018-04-01

Sputtering of lunar regolith by solar-wind protons and heavy ions with kinetic energies of about 1 keV/amu is an important erosive process that affects the lunar surface and exosphere. It plays an important role in changing the chemical composition and thickness of the surface layer, and in introducing material into the exosphere. Kinetic sputtering is well modeled and understood, but understanding of mechanisms of potential sputtering has lagged behind. In this study we differentiate the contributions of potential sputtering from the standard (kinetic) sputtering in changing the chemical composition and erosion rate of the lunar surface. Also we study the contribution of potential sputtering in developing the lunar exosphere. Our results show that potential sputtering enhances the total characteristic sputtering erosion rate by about 44%, and reduces sputtering time scales by the same amount. Potential sputtering also introduces more material into the lunar exosphere.

Flow and wakes in large wind farms. Final report for UpWind WP8

Energy Technology Data Exchange (ETDEWEB)

Barthelmie, R.J.; Frandsen, S.T.; Rathmann, O. (Risoe DTU (Denmark)); Hansen, K. (Technical Univ. of Denmark (DTU), Kgs. Lyngby (Denmark)); Politis, E.; Prospathopoulos, J. (CRES (Greece)); Schepers, J.G. (ECN, Petten (Netherlands)); Rados, K. (NTUA, Athens (Greece)); Cabezon, D. (CENER, Sarriguren (Spain)); Schlez, W.; Neubert, A.; Heath, M. (Garrad Hassan and Partners (Germany) (United Kingdom))

2011-02-15

This report summarises the research undertaken through the European Commission funded project UpWind Wp8:Flow. The objective of the work was to develop understanding of flow in large wind farms and to evaluate models of power losses due to wind turbine wakes focusing on complex terrain and offshore. A crosscutting activity was to improve and compare the performance of computational fluid dynamics models with wind farm models. The report contains 6 deliverable reports and guideline to wind farm wake analysis as appendices. (Author)

Quantifying accelerated soil erosion through ecological site-based assessments of wind and water erosion

Science.gov (United States)

This work explores how organising soil erosion assessments using established groupings of similar soils (ecological sites) can inform systems for managing accelerated soil erosion. We evaluated aeolian sediment transport and fluvial erosion rates for five ecological sites in southern New Mexico, USA...

Experimental study on influence of vegetation coverage on runoff in wind-water erosion crisscross region

Science.gov (United States)

Wang, Jinhua; Zhang, Ronggang; Sun, Juan

2018-02-01

Using artificial rainfall simulation method, 23 simulation experiments were carried out in water-wind erosion crisscross region in order to analyze the influence of vegetation coverage on runoff and sediment yield. The experimental plots are standard plots with a length of 20m, width of 5m and slope of 15 degrees. The simulation experiments were conducted in different vegetation coverage experimental plots based on three different rainfall intensities. According to the experimental observation data, the influence of vegetation coverage on runoff and infiltration was analyzed. Vegetation coverage has a significant impact on runoff, and the higher the vegetation coverage is, the smaller the runoff is. Under the condition of 0.6mm/min rainfall intensity, the runoff volume from the experimental plot with 18% vegetation coverage was 1.2 times of the runoff from the experimental with 30% vegetation coverage. What’s more, the difference of runoff is more obvious in higher rainfall intensity. If the rainfall intensity reaches 1.32mm/min, the runoff from the experimental plot with 11% vegetation coverage is about 2 times as large as the runoff from the experimental plot with 53%vegetation coverage. Under the condition of small rainfall intensity, the starting time of runoff in the experimental plot with higher vegetation coverage is later than that in the experimental plot with low vegetation coverage. However, under the condition of heavy rainfall intensity, there is no obvious difference in the beginning time of runoff. In addition, the higher the vegetation coverage is, the deeper the rainfall infiltration depth is.The results can provide reference for ecological construction carried out in wind erosion crisscross region with serious soil erosion.

Parametrization of the increase of the aeolian erosion threshold wind friction velocity due to soil moisture for arid and semi-arid areas

Directory of Open Access Journals (Sweden)

F. Fécan

1999-01-01

Full Text Available Large-scale simulation of the soil-derived dust emission in semi-arid regions needs to account for the influence of the soil moisture on the wind erosion threshold. Soil water retention consists of molecular adsorption on the soil grain surface and capillary forces between the grain. Interparticle capillary forces (characterized by the moisture tension are the main factor responsible for the increase of the wind erosion threshold observed when the soil moisture increases. When the soil moisture content is close to but smaller than the maximum amount of adsorbed water, w' (depending on the soil texture, these capillary forces are considered as not strong enough to significantly increase the erosion threshold. An expression of the moisture tension as a function of soil moisture and w' is derived from retention curves. From this expression, a parametrization of the ratio of the wet to dry erosion thresholds has been developed as a function of soil moisture and soil texture. The coefficients of this parametrization have been determined by using experimental data from the literature. An empirical relationship between w' and soil clay content has been established. The erosion threshold ratios simulated for different soil textures were found to be in good agreement with the experimental data.Key words. Atmospheric composition and structure (Aerosols and particles · Hydrology (soil moisture

The Major Cause of Observed Erosion Surge on the Beaches North ...

African Journals Online (AJOL)

Surges in coastal erosion north of Dar es Salaam city have been documented from 1977 to the early 1980s and around 1997/98. Analysis of the wind data shows that the documented increase in coastal erosion coincided with increased wind speeds. Extreme winds in excess of 10-11 m s-1 were experienced during ...

Effects of Long-term Conservation Tillage on Soil Nutrients in Sloping Fields in Regions Characterized by Water and Wind Erosion

Science.gov (United States)

Tan, Chunjian; Cao, Xue; Yuan, Shuai; Wang, Weiyu; Feng, Yongzhong; Qiao, Bo

2015-12-01

Conservation tillage is commonly used in regions affected by water and wind erosion. To understand the effects of conservation tillage on soil nutrients and yield, a long-term experiment was set up in a region affected by water and wind erosion on the Loess Plateau. The treatments used were traditional tillage (CK), no tillage (NT), straw mulching (SM), plastic-film mulching (PM), ridging and plastic-film mulching (RPM) and intercropping (In). Our results demonstrate that the available nutrients in soils subjected to non-traditional tillage treatments decreased during the first several years and then remained stable over the last several years of the experiment. The soil organic matter and total nitrogen content increased gradually over 6 years in all treatments except CK. The nutrient content of soils subjected to conservative tillage methods, such as NT and SM, were significantly higher than those in soils under the CK treatment. Straw mulching and film mulching effectively reduced an observed decrease in soybean yield. Over the final 6 years of the experiment, soybean yields followed the trend RPM > PM > SM > NT > CK > In. This trend has implications for controlling soil erosion and preventing non-point source pollution in sloping fields by sacrificing some food production.

Wind energy power plants (wind farms) review and analysis

Energy Technology Data Exchange (ETDEWEB)

Newbold, K B; McKeary, M [McMaster Univ., Hamilton, ON (Canada). McMaster Inst. of Environment and Health

2010-07-01

Global wind power capacity has increased by an average cumulative rate of over 30 percent over the past 10 years. Although wind energy emits no air pollutants and facilities can often share spaces with other activities, public opposition to wind power development is an ongoing cause of concern. Development at the local level in Ontario has been met with fierce opposition on the basis of health concerns, aesthetic values, potential environmental impacts, and economic risks. This report was prepared for the Town of Wasaga Beach, and examined some of the controversy surrounding wind power developments through a review of evidence found in the scientific literature. The impacts of wind power developments related to noise, shadow flicker, avian mortality, bats, and real estate values were evaluated. The study included details of interviews conducted with individuals from Ontario localities where wind farms were located. 77 refs., 1 tab., 1 fig., 2 appendices.

Rain erosion of wind turbine blade coatings using discrete water jets: Effects of water cushioning, substrate geometry, impact distance, and coating properties

DEFF Research Database (Denmark)

Zhang, Shizhong; Dam-Johansen, Kim; Bernad, Pablo L.

2015-01-01

Rapid and reliable rain erosion screening of blade coatings for wind turbines is a strong need in the coatings industry. One possibility in this direction is the use of discrete water jets, where so-called jet slugs are impacted on a coating surface. Previous investigations have mapped...... the influence of water jet slug velocity and impact frequency. In the present work, the effects on coating erosion of water cushioning, substrate curvature, and water nozzle-coating distance were explored. The investigations showed that in some cases water cushioning (the presence of a liquid film...... on the coating surface prior to impact) influences the erosion. Contrary to this, substrate curvature and the water nozzle-coating distance (

Erosion of Earthen Levees by Wave Action

Science.gov (United States)

Ozeren, Y.; Wren, D. G.; Reba, M. L.

2016-02-01

Earthen levees of aquaculture and irrigation reservoirs in the United States often experience significant erosion due to wind-generated waves. Typically constructed using local soils, unprotected levees are subjected to rapid erosion and retreat due to wind generated waves and surface runoff. Only a limited amount of published work addresses the erosion rates for unprotected levees, and producers who rely on irrigation reservoirs need an economic basis for selecting a protection method for vulnerable levees. This, in turn, means that a relationship between wave energy and erosion of cohesive soils is needed. In this study, laboratory experiments were carried out in order to quantify wave induced levee erosion and retreat. A model erodible bank was packed using a soil consisting of approximately 14% sand, 73% silt, and 13% clay in a 20.6 m long 0.7 m wide and 1.2 m deep wave tank at the USDA-ARS, National Sedimentation Laboratory in Oxford MS. The geometry of the levee face was monitored by digital camera and the waves were measured by means of 6 capacitance wave staffs. Relationships were established between levee erosion, edge and retreat rates, and incident wave energy.

CT features of appendiceal mucocele

Energy Technology Data Exchange (ETDEWEB)

Yu, Won Jong; Byun, Jae Young; Jung, Jung Im; Lee, Hae Gyu; Park, Young Ha; Shin, Kyung Sub [Catholic University Medical College, Seoul (Korea, Republic of)

1995-10-15

To evaluate the usefulness of CT features of appendiceal mucocele in the diagnosis and evaluation of complications. We retrospectively reviewed CT findings and compared with operative findings in 7 cases of pathologically proven appendiceal mucocele. CT findings such as location and extent of the lesion, tissue density, thickness or calcification of the wall, presence of adjacent inflammatory infiltration, and visualization of normal vermiform appendix were analyzed. Appendiceal mucocele was found as homogeneous low density cystic mass adjacent to the cecum, which has no surrounding inflammatory infiltration except in one case of perforation and one case of intussusception. Mean CT number measured in 4 cases was 21 Hounsfield unit. Thin curvilinear calcifications were noted along the cystic wall in 2 cases. Normal vermiform appendix couldn't be demonstrated in all cases. Appendiceal mucocele is characterized by homogeneously low density and thin walled cystic tumor adjacent to cecum without surrounding inflammatory infiltration, and absence of normal vermiform appendix on CT. Therefore, CT is valuable in preventing operative complications of appendiceal mucocele.

Bats and bat habitats : guidelines for wind power projects

International Nuclear Information System (INIS)

2010-03-01

Bat mortality has been documented at wind power projects in a number of habitats across North America. Wind power projects in Ontario have reported annual estimates ranging from 4 to 14 bat mortalities per turbine per year. This document presented guidance on identifying and addressing potential negative effects on bats and bat habitats during the planning, construction, and operation of wind power projects in Ontario. The guidelines supported the Ministry of Environment's renewable energy approval regulation and applied on both Crown and privately-owned land. The document presented the regulatory framework and discussed the assessment process for bats and bat habitats. This process included project site; records review; site investigation; and evaluation of significance. Other topics that were presented included an environmental impact study and an environmental effects monitoring plan such as post construction monitoring and post construction mitigation. Several appendices were also included regarding the potential effects of wind power project on bats; best management practices; methods for evaluating bat wildlife habitat; and post construction monitoring methods. 10 refs., 1 tab., 2 figs., 4 appendices.

Bats and bat habitats : guidelines for wind power projects

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-03-15

Bat mortality has been documented at wind power projects in a number of habitats across North America. Wind power projects in Ontario have reported annual estimates ranging from 4 to 14 bat mortalities per turbine per year. This document presented guidance on identifying and addressing potential negative effects on bats and bat habitats during the planning, construction, and operation of wind power projects in Ontario. The guidelines supported the Ministry of Environment's renewable energy approval regulation and applied on both Crown and privately-owned land. The document presented the regulatory framework and discussed the assessment process for bats and bat habitats. This process included project site; records review; site investigation; and evaluation of significance. Other topics that were presented included an environmental impact study and an environmental effects monitoring plan such as post construction monitoring and post construction mitigation. Several appendices were also included regarding the potential effects of wind power project on bats; best management practices; methods for evaluating bat wildlife habitat; and post construction monitoring methods. 10 refs., 1 tab., 2 figs., 4 appendices.

A pan-European quantitative assessment of soil loss by wind

Science.gov (United States)

Borrelli, Pasqualle; Lugato, Emanuele; Panagos, Panos

2016-04-01

Soil erosion by wind is a serious environmental problem often low perceived but resulting in severe soil degradation forms. On the long-term a considerable part of topsoil - rich in nutrient and organic matters - could be removed compromising the agricultural productivity and inducing an increased use of fertilizers. Field scale studies and observations proven that wind erosion is a serious problem in many European sites. The state-of-the-art suggests a scenario where wind erosion locally affects the temperate climate areas of the northern European countries, as well as the semi-arid areas of the Mediterranean region. However, observations, field measurements and modelling assessments are extremely limited and unequally distributed across Europe. It implies a lack of knowledge about where and when wind erosion occurs, limiting policy actions aimed at mitigating land degradation. To gain a better understanding about soil degradation process, the Soil Resource Assessment working group of the Joint Research Centre carried out the first pan-European assessments of wind-erodible fraction of soil (EF) (Geoderma, 232, 471-478, 2014) and land susceptibility to wind erosion (Land Degradation & Development, DOI: 10.1002/ldr.2318). Today's challenge is to integrate the insights archived by these pan-European assessments, local experiments and field-scale models into a new generation of regional-scale wind erosion models. A GIS version of the Revised Wind Erosion Equation (RWEQ) was developed with the aim to i) move a step forward into the aforementioned challenges, and ii) evaluate the soil loss potential due to wind erosion in the agricoltural land of the EU. The model scheme was designed to describe daily soil loss potential, combining spatiotemporal conditions of soil erodibility, crust factor, soil moisture content, vegetation coverage and wind erosivity at 1 km2 resolution. The average soil loss predicted by GIS-RWEQ in the EU arable land ranges from 0 to 39.9 Mg ha-1 yr

Evaluation of the RWEQ and SWEEP in simulating soil and PM10 loss from a portable wind tunnel

Science.gov (United States)

Wind erosion threatens sustainable agriculture and environmental quality in the Columbia Plateau region of the US Pacific Northwest. Wind erosion models such as Wind Erosion Prediction System (WEPS) and the Revised Wind Erosion Equation (RWEQ) have been developed as tools for identifying practices t...

Three procedures for estimating erosion from construction areas

International Nuclear Information System (INIS)

Abt, S.R.; Ruff, J.F.

1978-01-01

Erosion from many mining and construction sites can lead to serious environmental pollution problems. Therefore, erosion management plans must be developed in order that the engineer may implement measures to control or eliminate excessive soil losses. To properly implement a management program, it is necessary to estimate potential soil losses from the time the project begins to beyond project completion. Three methodologies are presented which project the estimated soil losses due to sheet or rill erosion of water and are applicable to mining and construction areas. Furthermore, the three methods described are intended as indicators of the state-of-the-art in water erosion prediction. The procedures herein do not account for gully erosion, snowmelt erosion, wind erosion, freeze-thaw erosion or extensive flooding

Analysis of ISEE-3/ICE solar wind data

Science.gov (United States)

Coplan, Michael A.

1989-01-01

Under the grant that ended November 11, 1988 work was accomplished in a number of areas, as follows: (1) Analysis of solar wind data; (2) Analysis of Giacobini/Zinner encounter data; (3) Investigation of solar wind and magnetospheric electron velocity distributions; and (4) Experimental investigation of the electronic structure of clusters. Reprints and preprints of publications resulting from this work are included in the appendices.

Interactions Between Wind Erosion, Vegetation Structure, and Soil Stability in Groundwater Dependent Plant Communities

Science.gov (United States)

Vest, K. R.; Elmore, A. J.; Okin, G. S.

2009-12-01

Desertification is a human induced global phenomenon causing a loss of biodiversity and ecosystem productivity. Semi-arid grasslands are vulnerable to anthropogenic impacts (i.e., groundwater pumping and surface water diversion) that decrease vegetation cover and increase bare soil area leading to a greater probability of soil erosion, potentially enhancing feedback processes associated with desertification. To enhance our understanding of interactions between anthropogenic, physical, and biological factors causing desertification, this study used a combination of modeling and field observations to examine the relationship between chronic groundwater pumping and vegetation cover change and its effects on soil erosion and stability. The work was conducted in Owens Valley California, where a long history of groundwater pumping and surface water diversion has lead to documented vegetation changes. The work examined hydrological, ecological and biogeochemical factors across thirteen sites in Owens Valley. We analyzed soil stability, vegetation and gap size, soil organic carbon, and we also installed Big Spring Number Eight (BSNE) catchers to calculate mass transport of aeolian sediment across sites. Mass transport calculations were used to validate a new wind erosion model that represents the effect of porous vegetation on surface windshear velocity. Results across two field seasons show that the model can be used to predict mass transport, and areas with increased groundwater pumping show a greater susceptibility to erosion. Sediment collected in BSNE catchers was positively correlated with site gap size. Additionally, areas with larger gap sizes have a greater threshold shear velocity and soil stability, yet mass transport was greater at these sites than at sites with smaller gap sizes. Although modeling is complicated by spatial variation in multiple model parameters (e.g., gap size, threshold shear velocity in gaps), our results support the hypothesis that soils

On the Material Characterisation of Wind Turbine Blade Coatings: The Effect of Interphase Coating–Laminate Adhesion on Rain Erosion Performance

Directory of Open Access Journals (Sweden)

Enrique Cortés

2017-09-01

Full Text Available Rain erosion damage, caused by repeated droplet impact on wind turbine blades, is a major cause for concern, even more so at offshore locations with larger blades and higher tip speeds. Due to the negative economic influence of blade erosion, all wind turbine Original Equipment Manufacturers (OEMs are actively seeking solutions. In most cases, since the surface coating plays a decisive role in the blade manufacture and overall performance, it has been identified as an area where a solution may be obtained. In this research, two main coating technologies have been considered: In-mould coatings (Gel coating applied during moulding on the entire blade surface and the post-mould coatings specifically developed for Leading Edge Protection (LEP. The coating adhesion and erosion is affected by the shock waves created by the collapsing water droplets on impact. The stress waves are reflected and transmitted to the laminate substrate, so microstructural discontinuities in coating layers and interfaces play a key role on its degradation and may accelerate erosion by delamination. Analytical and numerical models are commonly used to relate lifetime prediction and to identify suitable coating and composite substrate combinations based on their potential stress reduction on the interface. Nevertheless, in order to use them, it is necessary to measure the contact adhesion resistance of the multi-layered system interfaces. The rain erosion performance is assessed using an accelerated testing technique, whereby the test material is repeatedly impacted at high speed with water droplets in a Whirling Arm Rain Erosion Rig (WARER. The materials, specifically the coating–laminate interphase region and acoustic properties, are further characterised by several laboratory tests, including Differential Scanning Calorimetry (DSC, pull-off testing, peeling–adhesion testing and nanoindentation testing. This body of work includes a number of case studies. The first case

On the Material Characterisation of Wind Turbine Blade Coatings: The Effect of Interphase Coating–Laminate Adhesion on Rain Erosion Performance

Science.gov (United States)

Cortés, Enrique; Sánchez, Fernando; Madramany, Borja

2017-01-01

Rain erosion damage, caused by repeated droplet impact on wind turbine blades, is a major cause for concern, even more so at offshore locations with larger blades and higher tip speeds. Due to the negative economic influence of blade erosion, all wind turbine Original Equipment Manufacturers (OEMs) are actively seeking solutions. In most cases, since the surface coating plays a decisive role in the blade manufacture and overall performance, it has been identified as an area where a solution may be obtained. In this research, two main coating technologies have been considered: In-mould coatings (Gel coating) applied during moulding on the entire blade surface and the post-mould coatings specifically developed for Leading Edge Protection (LEP). The coating adhesion and erosion is affected by the shock waves created by the collapsing water droplets on impact. The stress waves are reflected and transmitted to the laminate substrate, so microstructural discontinuities in coating layers and interfaces play a key role on its degradation and may accelerate erosion by delamination. Analytical and numerical models are commonly used to relate lifetime prediction and to identify suitable coating and composite substrate combinations based on their potential stress reduction on the interface. Nevertheless, in order to use them, it is necessary to measure the contact adhesion resistance of the multi-layered system interfaces. The rain erosion performance is assessed using an accelerated testing technique, whereby the test material is repeatedly impacted at high speed with water droplets in a Whirling Arm Rain Erosion Rig (WARER). The materials, specifically the coating–laminate interphase region and acoustic properties, are further characterised by several laboratory tests, including Differential Scanning Calorimetry (DSC), pull-off testing, peeling–adhesion testing and nanoindentation testing. This body of work includes a number of case studies. The first case study compares

On the Material Characterisation of Wind Turbine Blade Coatings: The Effect of Interphase Coating-Laminate Adhesion on Rain Erosion Performance.

Science.gov (United States)

Cortés, Enrique; Sánchez, Fernando; O'Carroll, Anthony; Madramany, Borja; Hardiman, Mark; Young, Trevor M

2017-09-28

Rain erosion damage, caused by repeated droplet impact on wind turbine blades, is a major cause for concern, even more so at offshore locations with larger blades and higher tip speeds. Due to the negative economic influence of blade erosion, all wind turbine Original Equipment Manufacturers (OEMs) are actively seeking solutions. In most cases, since the surface coating plays a decisive role in the blade manufacture and overall performance, it has been identified as an area where a solution may be obtained. In this research, two main coating technologies have been considered: In-mould coatings (Gel coating) applied during moulding on the entire blade surface and the post-mould coatings specifically developed for Leading Edge Protection (LEP). The coating adhesion and erosion is affected by the shock waves created by the collapsing water droplets on impact. The stress waves are reflected and transmitted to the laminate substrate, so microstructural discontinuities in coating layers and interfaces play a key role on its degradation and may accelerate erosion by delamination. Analytical and numerical models are commonly used to relate lifetime prediction and to identify suitable coating and composite substrate combinations based on their potential stress reduction on the interface. Nevertheless, in order to use them, it is necessary to measure the contact adhesion resistance of the multi-layered system interfaces. The rain erosion performance is assessed using an accelerated testing technique, whereby the test material is repeatedly impacted at high speed with water droplets in a Whirling Arm Rain Erosion Rig (WARER). The materials, specifically the coating-laminate interphase region and acoustic properties, are further characterised by several laboratory tests, including Differential Scanning Calorimetry (DSC), pull-off testing, peeling-adhesion testing and nanoindentation testing. This body of work includes a number of case studies. The first case study compares two

[Biological soil crust nitrogenase activity and its responses to hydro-thermic factors in different erosion regions on the Loess Plateau, China].

Science.gov (United States)

Ming, Jiao; Zhao, Yun-Ge; Xu, Ming-Xiang; Yang, Li-Na; Wang, Ai-Guo

2013-07-01

Based on field survey, the biological soil crusts at their stable development stage were collected from the water erosion region, water-wind erosion region, and wind erosion region on the Loess Plateau, aimed to study the effects of the variations of moisture and temperature on the crusts nitrogenase activity (NA). The NA of the crusts in the erosion regions decreased in the order of water erosion region (127.7 micromol x m(-2) x h(-1)) > water-wind erosion region (34.6 micromol x m(-2) x h(-1)) > wind erosion region (6.0 micromol x m(-2) x h(-1)), and the optimal temperature for the crust nitrogen fixation was 35 degrees C, 25 degrees C, and 15 degrees C, respectively. At the optimal temperature and 100% -40% field water-holding capacity, the NA of the crusts from the water erosion and water-wind erosion regions had no significant difference. The NA of the crusts from the wind erosion region was more sensitive to the variation of moisture, showing a dramatic decline when the moisture decreased to 80% field water-holding capacity, and totally lost when the moisture decreased to 20% field water-holding capacity. The differences in the NA of the crusts from the three erosion regions and the responses of the NA to the variations of moisture and temperature were likely associated with the climate, environment, and the crust species composition.

Vegetation morphologic and aerodynamic characteristics reduce aeolian erosion.

Science.gov (United States)

Miri, Abbas; Dragovich, Deirdre; Dong, Zhibao

2017-10-09

Vegetation cover is crucial to controlling aeolian erosion but highly efficient vegetation is critical. How this efficiency is influenced by vegetation response to airflow is not clear. Here we evaluate the responses of Cosmos bipinnatus and Ligustrum lucidum Ait to a range of wind speeds in a wind tunnel. For both species, we calculate shelter effect and sand flux. We show that plant effectiveness in reducing wind speed and sediment transport is linked to their aerodynamic response to airflow which results from their morphology. We demonstrate that in low-density cover the flow-response and resistance of individuals is most critical in the optimal effectiveness of a canopy. Our wind tunnel experiment suggests that vegetation morphology and structure must be priority parameters in facilitating aeolian erosion control.

Control of Eolian soil erosion from waste site surface barriers

International Nuclear Information System (INIS)

Ligotke, M.W.

1994-11-01

Physical models were tested in a wind tunnel to determine optimum surface-ravel admixtures for protecting silt-loam soil from erosion by, wind and saltating, sand stresses. The tests were performed to support the development of a natural-material surface barrier for and waste sites. Plans call for a 2-m deep silt-loam soil reservoir to retain infiltrating water from rainfall and snowmelt. The objective of the study was to develop a gravel admixture that would produce an erosion-resistant surface layer during, periods of extended dry climatic stress. Thus, tests were performed using simulated surfaces representing dry, unvegetated conditions present just after construction, after a wildfire, or during an extended drought. Surfaces were prepared using silt-loam soil mixed with various grades of sand and Travel. Wind-induced surface shear stresses were controlled over the test surfaces, as were saltating, sand mass flow rates and intensities. Tests were performed at wind speeds that approximated and exceeded local 100-year peak gust intensities. Surface armors produced by pea gravel admixtures were shown to provide the best protection from wind and saltating sand stresses. Compared with unprotected silt-loam surfaces, armored surfaces reduced erosion rates by more than 96%. Based in part on wind tunnel results, a pea gravel admixture of 15% will be added to the top 1 in of soil in a prototype barrier under construction in 1994. Field tests are planned at the prototype site to provide data for comparison with wind tunnel results

Compressor Impeller Erosion Resistant Surface Treatment

National Research Council Canada - National Science Library

Riley, Michael

2000-01-01

...). Coatings based on tungsten carbide tantalum carbide. titanium carbide all with a cobalt matrix were evaluated for high velocity particle erosion in conventional wear test studies as well as wind tunnel testing...

Appendiceal Abscesses Reduced in Size by Drainage of Pus from the Appendiceal Orifice during Colonoscopy: A Report of Three Cases

Directory of Open Access Journals (Sweden)

Shinjiro Kobayashi

2014-11-01

Full Text Available Interval appendectomy (IA for appendiceal abscesses is useful for avoiding extended surgery and preventing postoperative complications. However, IA has problems in that it takes time before an abscess is reduced in size in some cases and in that elective surgery may result in a delay in treatment in patients with a malignant tumor of the appendix. In order to rule out malignancy, we performed colonoscopy on three patients with an appendiceal abscess that did not decrease in size 5 or more days after IA. After malignancy had been ruled out by examination of the area of the appendiceal orifice, the appendiceal orifice was compressed with a colonoscope, and a catheter was inserted through the orifice. Then, drainage of pus was observed from the appendiceal orifice into the cecal lumen. Computed tomography performed 3 days after colonoscopy revealed a marked reduction in abscess size in all patients. No endoscopy-related complication was noted. Colonoscopy in patients with an appendiceal abscess may not only differentiate malignant tumors, but also accelerate reduction in abscess size.

Wind-eroded silicate as a source of hydrogen peroxide on Mars

DEFF Research Database (Denmark)

Bak, Ebbe Norskov; Merrison, Jonathan P.; Jensen, Svend Knak

-sists of silicates [4] that due to wind erosion has a very fine grained texture. Based on the composition of the surface material and investigations showing that crushing of silicates can give rise to reactive oxygen species [5], we hypothesized that wind erosion of silicates can explain the reactivity of Martian...... soil. Wind-erosion of silicate could thus be one of several causes of the soil’s reactivity. As our experiments show, the globally distributed wind eroded silicate dust can lead to the production of hydrogen peroxide which might explain the reactivity of the Martian soil. The reactivity of eroded...

Birds and wind power. Technical report 1977-1982; Faglar och vindkraft. Teknisk rapport 1977-1982

Energy Technology Data Exchange (ETDEWEB)

Karlsson, Johnny

1983-02-15

The impact of wind power plants on birds has been studied. The risk of migrating birds colliding with high buildings has been investigated. Different hazards and accidents are described and reported in 12 appendices. Preliminary data from the sites of wind power plants are presented.

Assessment of wind erosion threat for soils in cadastral area of Hajske

International Nuclear Information System (INIS)

Muchova, Z.; Stredanska, A.

2008-01-01

This contribution illustrates the application of methods of erosion threat assessment in lan adaptation projects. Calculations of the soil erosion index of particular soil blocks are demonstrated for the cadastral area of Hajske. Two methods for assessment of erosion threat have been applied. First the assessment based on the ecological soil-quality units (ESQU) has been performed. Next, the Pasak method for a detailed analysis of the soil erosion threat was applied. Both of the mentioned approaches are recommended for the land adaption projects. Based on the results, the soil blocks have been ranked by their soil erosion threat. (authors)

Design, construction and calibration of a portable boundary layer wind tunnel for field use

Science.gov (United States)

Wind tunnels have been used for several decades to study wind erosion processes. Portable wind tunnels offer the advantage of testing natural surfaces in the field, but they must be carefully designed to insure that a logarithmic boundary layer is formed and that wind erosion processes may develop ...

Soil Erosion: Advanced Crop and Soil Science. A Course of Study.

Science.gov (United States)

Miller, Larry E.

The course of study represents the last of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil erosion. Upon completion of the two day lesson, the student will be able to: (1) define conservation, (2) understand how erosion takes place, and (3) list ways of controlling wind and water erosion.…

Effects of offshore wind energy developments on navigation and commercial shipping

Energy Technology Data Exchange (ETDEWEB)

Petts, J W

1999-07-01

This report summarises the findings of a study examining the impact of the development of offshore wind farms on commercial shipping and navigation in the area of the UK continental shelf. The study methodology is described, and a review of previous studies is carried out. Technological and current developments, wind farm layout and physical limitations, interaction with marine users, and a quantitative assessment are examined, and the protection of offshore wind farms is considered. Appendices give details of admiralty charts and publications, maps, and chart markings for wind turbines. (UK)

Sound wave contours around wind turbine arrays

International Nuclear Information System (INIS)

Van Beek, A.; Van Blokland, G.J.

1993-02-01

Noise pollution is an important factor in selecting suitable sites for wind turbines in order to realize 1000 MW of wind power as planned by the Dutch government for the year 2000. Therefore an accurate assessment of wind turbine noise is important. The amount of noise pollution from a wind turbine depends on the wind conditions. An existing standard method to assess wind turbine noise is supplemented and adjusted. In the first part of the investigation the method was developed and applied for a solitary sound source. In the second part attention is paid to the use of the method for wind turbine arrays. It appears that the adjusted method results in a shift of the contours of the permitted noise level. In general the contours are 15-25% closer to the wind farm, which means that the minimal permitted distance between houses and wind turbine arrays can be reduced. 14 figs., 1 tab., 4 appendices, 7 refs

Predicción de la erosión eólica potencial con el modelo EWEQ en dos suelos loesicos: efectos de las condiciones climáticas Wind erosion prediction with the EWEQ model in two loess soils: effects of climatic condition

Directory of Open Access Journals (Sweden)

Silvia Beatriz Aimar

2011-12-01

Full Text Available La erosión eólica potencial del suelo (EEP es un dato básico utilizado en varios modelos de predicción para calcular la erosión eólica de suelos agrícolas. El objetivo de este estudio fue cuantificar la EEP de un Haplustol y un Ustipsammente de la Región Semiárida Pampeana (RSP y compararla con las predicciones del modelo Ecuación de Erosión Eólica en Español (EWEQ, realizadas con diferentes factores climáticos (C. Se efectuaron mediciones de EEP a campo durante un año en ambos suelos, mantenidos sin cobertura y con mínima rugosidad. Los resultados indicaron que la EEP medida a campo fue mayor en el Ustipsammente (270 Mg ha-1 año-1 que en el Haplustol (40 Mg ha-1 año -1 , con una reducción en el espesor del horizonte de 21,3 y 3,1 mm, respectivamente. La erosión del Ustipsammente fue dos veces mayor en primavera-verano que en otoño-invierno. Este efecto no se observó en el Haplustol, debido a su menor desecamiento y mayores contenidos de humedad luego de las lluvias. La erosión del Haplustol, por desecarse más lentamente luego de una lluvia, fue más condicionada por las precipitaciones que la del Ustipsammente. Un 40% de la erosión de ambos suelos fue definida por la duración de las tormentas. Las tasas de erosión (EEP por unidad de tiempo, Qt se correlacionaron positivamente con la velocidad promedio del viento (V, ajustando a una función polinómica en ambos suelos. A la misma V, Qt fue siempre mayor en el Ustipsammente. La EEP calculada con la EWEQ, utilizando el factor C correspondiente al año de muestreo (30,3, fue la más semejante a la erosión medida a campo, aunque el modelo la subestimó en un 43% en el Haplustol y en un 18% en el Ustipsammente. La EWEQ deberá ofrecer al usuario distintos factores C para poder predecir EEP en escenarios climáticos variables.The potential wind erosion of a soil (EEP is a basic data for predicting wind erosion of agricultural soils in most wind erosion prediction models

Estimation Model of Soil Freeze-Thaw Erosion in Silingco Watershed Wetland of Northern Tibet

OpenAIRE

Kong, Bo; Yu, Huan

2013-01-01

The freeze-thaw (FT) erosion is a type of soil erosion like water erosion and wind erosion. Limited by many factors, the grading evaluation of soil FT erosion quantities is not well studied. Based on the comprehensive analysis of the evaluation indices of soil FT erosion, we for the first time utilized the sensitivity of microwave remote sensing technology to soil moisture for identification of FT state. We established an estimation model suitable to evaluate the soil FT erosion quantity in S...

Wind energy mission analysis. Final report, appendices A--J. [USA

Energy Technology Data Exchange (ETDEWEB)

1977-02-18

Information is presented concerning meteorological data and supporting analyses, gross energy consumption patterns and end-use analysis, analysis for industrial applications of wind energy conversion systems (WECS), analysis for residential applications of WECS, analysis for application of WECS to communities remote from utility grids, analysis for agricultural applications of WECS, regional evaluation of the economics of wind turbine generation to the U. S. electric utility district, impact of storage on WECS, financial analysis techniques, and system spacing.

Wind tunnel simulation of Martian sand storms

Science.gov (United States)

Greeley, R.

1980-01-01

The physics and geological relationships of particles driven by the wind under near Martian conditions were examined in the Martian Surface Wind Tunnel. Emphasis was placed on aeolian activity as a planetary process. Threshold speeds, rates of erosion, trajectories of windblown particles, and flow fields over various landforms were among the factors considered. Results of experiments on particles thresholds, rates of erosion, and the effects of electrostatics on particles in the aeolian environment are presented.

Microbiology of Wind-eroded Sediments: Current Knowledge and Future Research Directions

Science.gov (United States)

Wind erosion is a threat to the sustainability and productivity of soils that takes place at local, regional, and global scales. Current estimates of cost of wind erosion have not included the costs associated with the loss of soil biodiversity and reduced ecosystem functions. Microorganisms carrie...

Special Education Finance in California. Technical Appendices

Science.gov (United States)

Hill, Laura; Warren, Paul; Murphy, Patrick; Ugo, Iwunze; Pathak, Aditi

2016-01-01

This document presents the technical appendices that accompany the full report, "Special Education Finance in California." The appendices include: (1) Problems with AB 602 and Other State Funding Programs for Special Education; (2) Additional Figures for Analysis of Distribution of Students with Disabilities; (3) Using Supplemental and…

Wind tunnel tests of biodegradable fugitive dust suppressants being considered to reduce soil erosion by wind at radioactive waste construction sites

International Nuclear Information System (INIS)

Ligotke, M.W.; Dennis, G.W.; Bushaw, L.L.

1993-10-01

Wind tunnel tests were performed of three fugitive dust control agents derived from potato and sugar beet products. These materials are being considered for use as dust suppressants to reduce the potential for transport of radioactive materials by wind from radioactive waste construction and remediation sites. Soil and dust control agent type, solution concentrations, application quantities, aging (or drying) conditions, surface disturbance, and wind and saltating sand eolian erosive stresses were selected and controlled to simulate application and exposure of excavated soil surfaces in the field. A description of the tests, results, conclusions, and recommendations are presented in this report. The results of this study indicate that all three dust control agents can protect exposed soil surfaces from extreme eolian stresses. It is also clear that the interaction and performance of each agent with various soil types may differ dramatically. Thus, soils similar to that received from ML should be best protected by high concentration (∼2.5%) solutions of potato starch at low water application levels (∼1 to 2 L/m 2 ). Because the effectiveness of PS on this soil type is degraded after a moderate amount of simulated rainfall, other options or additives should be considered if surfaces are to be protected for long intervals or during periods of intermittent rainfall and hot, windy conditions. On the other hand, XDCA should be considered when excavating sandy soils. It should be noted, however, that because the Hanford soil test results are based on a small number of tests, it would be prudent to perform additional tests prior to selecting a fugitive dust control agent for use at the Hanford Site. While fermented potato waste was not the best fixative used on either soil, it did perform reasonably well on both soil types (better than XDCA on Idaho soil and better than PS on Hanford soil)

Wind erosion risk in the southwest of Buenos Aires Province, Argentina, and its relationship to the productivity index

Science.gov (United States)

Silenzi, Juan C.; Echeverría, Nora E.; Vallejos, Adrián G.; Bouza, Mariana E.; De Lucia, Martín P.

2012-01-01

Wind erosion risk (WER) for soils of each municipality in the southwest (SW) of Buenos Aires Province (10,491,172 ha) was determined using the wind erosion equation (WEQ) model. WER results from multiplying the soil erodibility index (" I") of the soil by the climatic factor ( C). WER (Mg ha -1 year -1) of each municipality was: Bahía Blanca: 22.4, Coronel Dorrego: 18.6, Coronel Pringles: 4.5, Coronel Rosales: 48.2, Coronel Suárez: 4.5, Guaminí: 3.0, Patagones: 104.6, Puan: 12.2, Saavedra: 3.0, Tornquist: 6.8, and Villarino: 31.7. The maximum weighted average of " I" (Mg ha -1 year -1) corresponded to Coronel Rosales (87.6), Patagones (87.2), Villarino (85.7), Puan (67.9); Guaminí (59.6), Coronel Dorrego (53.1), and Bahía Blanca (39.3); the remaining municipalities ranged between 34.9 and 32.1 Mg ha -1 year -1. The highest C (%) corresponded to Patagones (120), Bahía Blanca (57), Coronel Rosales (55), Villarino (37), Coronel Dorrego (35), Tornquist (21), and Puan (18); for the remaining municipalities it was 14%. The productivity index (PI) is known to establish a numerical value of the productive capacity of lands. The relationship between WER and PI, weighted averages, in all the studied municipalities was fitted by means of a linear model, WER (Mg ha -1 year -1) = 95.23 - 2.09 * PI (%) ( R2 = 66%), and a second-order polynomial model, WER (Mg ha -1 year -1) = 139.41 - 5.86 * PI (%) + 0.07 * PI 2 (%) ( R2 = 74%). No statistically significant relationship was found between WER and PI for each municipality.

Cumulative effects of wind turbines. Volume 3: Report on results of consultations on cumulative effects of wind turbines on birds

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

This report gives details of the consultations held in developing the consensus approach taken in assessing the cumulative effects of wind turbines. Contributions on bird issues, and views of stakeholders, the Countryside Council for Wales, electric utilities, Scottish Natural Heritage, and the National Wind Power Association are reported. The scoping of key species groups, where cumulative effects might be expected, consideration of other developments, the significance of any adverse effects, mitigation, regional capacity assessments, and predictive models are discussed. Topics considered at two stakeholder workshops are outlined in the appendices.

Appendiceal diameter: CT versus sonographic measurements

Energy Technology Data Exchange (ETDEWEB)

Orscheln, Emily S. [University of Cincinnati Medical Center, Department of Radiology, Cincinnati, OH (United States); Trout, Andrew T. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

2016-03-15

Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality. To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis. We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test. We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis. Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis. (orig.)

Appendiceal diameter: CT versus sonographic measurements

International Nuclear Information System (INIS)

Orscheln, Emily S.; Trout, Andrew T.

2016-01-01

Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality. To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis. We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test. We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis. Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis. (orig.)

Sand transport, erosion and granular electrification

DEFF Research Database (Denmark)

Merrison, J.P.

2012-01-01

is expanding our current understanding and outline the areas of advancement needed in the future. Presentation is made of current models for wind driven detachment/entrainment and the transport rates of sand and dust, including the effects of contact induced grain electrification. This ubiquitous phenomenon...... can affect grain transport through the generation of intense electric fields and processes of electrostatic assembly. Importantly the transport of sand is characterized by saltation, which is known to be an active process for erosion and therefore a source for dust and sand formation. Using novel...... erosion simulation techniques the link between grain transport rates and erosion rates has been quantified. Furthermore this can be linked to production rates for dust and has been associated with chemical and mineral alteration through a process of mechanical activation of fractured surfaces. This work...

Wind Energy and Air Emission Reduction Benefits: A Primer

Energy Technology Data Exchange (ETDEWEB)

Jacobson, D.; High, C.

2008-02-01

This document provides a summary of the impact of wind energy development on various air pollutants for a general audience. The core document addresses the key facts relating to the analysis of emission reductions from wind energy development. It is intended for use by a wide variety of parties with an interest in this issue, ranging from state environmental officials to renewable energy stakeholders. The appendices provide basic background information for the general reader, as well as detailed information for those seeking a more in-depth discussion of various topics.

Appendiceal Adenocarcinoma Presenting as a Rectal Polyp

Directory of Open Access Journals (Sweden)

Erin Fitzgerald

2016-02-01

Full Text Available Appendiceal adenocarcinoma typically presents as an incidentally noted appendiceal mass, or with symptoms of right lower quadrant pain that can mimic appendicitis, but local involvement of adjacent organs is uncommon, particularly as the presenting sign. We report on a case of a primary appendiceal cancer initially diagnosed as a rectal polyp based on its appearance in the rectal lumen. The management of the patient was in keeping with standard practice for a rectal polyp, and the diagnosis of appendiceal adenocarcinoma was made intraoperatively. The operative strategy had to be adjusted due to this unexpected finding. Although there are published cases of appendiceal adenocarcinoma inducing intussusception and thus mimicking a cecal polyp, there are no reports in the literature describing invasion of the appendix through the rectal wall and thus mimicking a rectal polyp. The patient is a 75-year-old female who presented with spontaneous hematochezia and, on colonoscopy, was noted to have a rectal polyp that appeared to be located within a diverticulum. When endoscopic mucosal resection was not successful, she was referred to colorectal surgery for a low anterior resection. Preoperative imaging was notable for an enlarged appendix adjacent to the rectum. Intraoperatively, the appendix was found to be densely adherent to the right lateral rectal wall. An en bloc resection of the distal sigmoid colon, proximal rectum and appendix was performed, with pathology demonstrating appendiceal adenocarcinoma that invaded through the rectal wall. The prognosis in this type of malignancy weighs heavily on whether or not perforation and spread throughout the peritoneal cavity have occurred. In this unusual presentation, an en bloc resection is required for a complete resection and to minimize the risk of peritoneal spread. Unusual appearing polyps do not always originate from the bowel wall. Abnormal radiographic findings adjacent to an area of

Analysis of wind energy market and jobs in France

International Nuclear Information System (INIS)

Perot, Olivier; Autier, Emmanuel

2014-10-01

This report presents an overview of wind energy production and of the wind energy sector in France. Illustrated by maps, graphs and tables, it notices and comments the steady situation of jobs, and the existence of a structured value chain, and a variety of actors. It describes and analyses job locations in metropolitan France and outlines that the wind energy sector is a lever for development and creates opportunities for regions. The second part addresses the wind energy market. It proposes an assessment of the French market (a new start in 2014, a competitive market with some dynamic regions) and a review of the technological evolution of the wind energy industry (continuous evolutions, strong emergence of wind farms, and an increasing production). Appendices propose presentations of actors per category (developers, operators, machine manufacturers, component manufacturer, public works and logistics, maintenance, consultants and experts), and sheets indicating the presence of actors, installed power and number of wind farms in the different French regions

Control of eolic erosion in a coal Port, by means of re-vegetation of arid areas and operational procedures

International Nuclear Information System (INIS)

Velasquez Pilar

1992-01-01

To the phenomenon of haulage of floor particles for the wind is known as erosion by deflation, and one in the ways of eolic erosion existent, although many authors constitutes they refer to her as eolic erosion. The eolic erosion includes the movement processes, transport, separation and deposition, it can present in any area that presents the following conditions: 1) Soil dry and loose until certain finely divided degree, 2) flat surface with little or any vegetable cover, 3) quite extensive land 4) sufficiently strong wind to transport the earth particles. It is considered that to begin the movement of particles 0.1 mm of diameter winds they are needed to 30 cm of height of 4,4m/s (FAO, 1961). All these conditions are presented in Port Bolivar in more or smaller measure. In port Bolivar two main groups of areas have been identified in process of material movement

Erosion and erosion-corrosion

International Nuclear Information System (INIS)

Isomoto, Yoshinori

2008-01-01

It is very difficult to interpret the technical term of erosion-corrosion' which is sometimes encountered in piping systems of power plants, because of complicated mechanisms and several confusing definitions of erosion-corrosion phenomena. 'FAC (flow accelerated corrosion)' is recently introduced as wall thinning of materials in power plant systems, as a representative of 'erosion-corrosion'. FAC is, however, not necessarily well understood and compared with erosion-corrosion. This paper describes firstly the origin, definition and fundamental understandings of erosion and erosion-corrosion, in order to reconsider and reconfirm the phenomena of erosion, erosion-corrosion and FAC. Next, typical mapping of erosion, corrosion, erosion-corrosion and FAC are introduced in flow velocity and environmental corrosiveness axes. The concept of damage rate in erosion-corrosion is finally discussed, connecting dissolution rate, mass transfer of metal ions in a metal oxide film and film growth. (author)

Significance of appendiceal thickening in association with typhlitis in pediatric oncology patients

International Nuclear Information System (INIS)

McCarville, M.B.; Thompson, J.; Adelman, C.S.; Lee, M.O.; Li, C.; Alsammarae, D.; Rao, B.N.; May, M.V.; Jones, S.C.; Sandlund, J.T.

2004-01-01

Background: The management of pediatric oncology patients with imaging evidence of appendiceal thickening is complex because they are generally poor surgical candidates and often have confounding clinical findings. Objective: We sought to determine the significance of appendiceal thickening in pediatric oncology patients who also had typhlitis. Specifically, we evaluated the impact of this finding on the duration of typhlitis, its clinical management, and outcome. Materials and methods: From a previous review of the management of typhlitis in 90 children with cancer at our institution, we identified 4 with imaging evidence of appendiceal thickening. We compared colonic wall measurements, duration of typhlitis symptoms, management, and outcome of patients with appendiceal thickening and typhlitis to patients with typhlitis alone. Results: There was no significant difference in duration of typhlitis symptoms between patients with typhlitis only (15.6 ± 1.2 days) and those with typhlitis and appendiceal thickening (14.5 ± 5.8 days; P = 0.9). Two patients with appendiceal thickening required surgical treatment for ischemic bowel, and two were treated medically. Only one patient in the typhlitis without appendiceal thickening group required surgical intervention. There were no deaths in children with appendiceal thickening; two patients died of complications of typhlitis alone. (orig.)

Market analysis of shale oil co-products. Appendices

Energy Technology Data Exchange (ETDEWEB)

1980-12-01

Data are presented in these appendices on the marketing and economic potential for soda ash, aluminia, and nahcolite as by-products of shale oil production. Appendices 1 and 2 contain data on the estimated capital and operating cost of an oil shales/mineral co-products recovery facility. Appendix 3 contains the marketing research data.

12 CFR Appendices F-I to Part 41 - [Reserved

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 1 2010-01-01 2010-01-01 false [Reserved] F Appendices F-I to Part 41 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY FAIR CREDIT REPORTING Appendices F-I to Part 41[Reserved] ...

Nourishment of perched sand dunes and the issue of erosion control in the Great Lakes

Science.gov (United States)

Marsh, William M.

1990-09-01

Although limited in coverage, perched sand dunes situated on high coastal bluffs are considered the most prized of Great Lakes dunes. Grand Sable Dunes on Lake Superior and Sleeping Bear Dunes on Lake Michigan are featured attractions of national lakeshores under National Park Service management. The source of sand for perched dunes is the high bluff along their lakeward edge. As onshore wind crosses the bluff, flow is accelerated upslope, resulting in greatly elevated levels of wind stress over the slope brow. On barren, sandy bluffs, wind erosion is concentrated in the brow zone, and for the Grand Sable Bluff, it averaged 1 m3/yr per linear meter along the highest sections for the period 1973 1983. This mechanism accounts for about 6,500 m3 of sand nourishment to the dunefield annually and clearly has been the predominant mechanism for the long-term development of the dunefield. However, wind erosion and dune nourishment are possible only where the bluff is denuded of plant cover by mass movements and related processes induced by wave erosion. In the Great Lakes, wave erosion and bluff retreat vary with lake levels; the nourishment of perched dunes is favored by high levels. Lake levels have been relatively high for the past 50 years, and shore erosion has become a major environmental issue leading property owners and politicians to support lake-level regulation. Trimming high water levels could reduce geomorphic activity on high bluffs and affect dune nourishment rates. Locally, nourishment also may be influenced by sediment accumulation associated with harbor protection facilities and by planting programs aimed at stabilizing dunes.

Solid particle erosion of polymers and composites

Science.gov (United States)

Friedrich, K.; Almajid, A. A.

2014-05-01

After a general introduction to the subject of solid particle erosion of polymers and composites, the presentation focusses more specifically on the behavior of unidirectional carbon fiber (CF) reinforced polyetheretherketone (PEEK) composites under such loadings, using different impact conditions and erodents. The data were analyzed on the basis of a newly defined specific erosive wear rate, allowing a better comparison of erosion data achieved under various testing conditions. Characteristic wear mechanisms of the CF/PEEK composites consisted of fiber fracture, matrix cutting and plastic matrix deformation, the relative contribution of which depended on the impingement angles and the CF orientation. The highest wear rates were measured for impingement angles between 45 and 60°. Using abrasion resistant neat polymer films (in this case PEEK or thermoplastic polyurethane (TPU) ones) on the surface of a harder substrate (e.g. a CF/PEEK composite plate) resulted in much lower specific erosive wear rates. The use of such polymeric films can be considered as a possible method to protect composite surfaces from damage caused by minor impacts and erosion. In fact, they are nowadays already successfully applied as protections for wind energy rotor blades.

Wind Energy Resource Assessment on Alaska Native Lands in Cordova Region of Prince William Sound

Energy Technology Data Exchange (ETDEWEB)

Whissel, John C. [Native Village of Eyak, Cordova, AK (United States); Piche, Matthew [Native Village of Eyak, Cordova, AK (United States)

2015-06-29

The Native Village of Eyak (NVE) has been monitoring wind resources around Cordova, Alaska in order to determine whether there is a role for wind energy to play in the city’s energy scheme, which is now supplies entirely by two run-of-the-river hydro plants and diesel generators. These data are reported in Appendices A and B. Because the hydro resources decline during winter months, and wind resources increase, wind is perhaps an ideal counterpart to round out Cordova’s renewable energy supply. The results of this effort suggests that this is the case, and that developing wind resources makes sense for our small, isolated community.

The Monitoring Erosion of Agricultural Land and spatial database of erosion events

Science.gov (United States)

Kapicka, Jiri; Zizala, Daniel

2013-04-01

In 2011 originated in The Czech Republic The Monitoring Erosion of Agricultural Land as joint project of State Land Office (SLO) and Research Institute for Soil and Water Conservation (RISWC). The aim of the project is collecting and record keeping information about erosion events on agricultural land and their evaluation. The main idea is a creation of a spatial database that will be source of data and information for evaluation and modeling erosion process, for proposal of preventive measures and measures to reduce negative impacts of erosion events. A subject of monitoring is the manifestations of water erosion, wind erosion and slope deformation in which cause damaged agriculture land. A website, available on http://me.vumop.cz, is used as a tool for keeping and browsing information about monitored events. SLO employees carry out record keeping. RISWC is specialist institute in the Monitoring Erosion of Agricultural Land that performs keeping the spatial database, running the website, managing the record keeping of events, analysis the cause of origins events and statistical evaluations of keeping events and proposed measures. Records are inserted into the database using the user interface of the website which has map server as a component. Website is based on database technology PostgreSQL with superstructure PostGIS and MapServer UMN. Each record is in the database spatial localized by a drawing and it contains description information about character of event (data, situation description etc.) then there are recorded information about land cover and about grown crops. A part of database is photodocumentation which is taken in field reconnaissance which is performed within two days after notify of event. Another part of database are information about precipitations from accessible precipitation gauges. Website allows to do simple spatial analysis as are area calculation, slope calculation, percentage representation of GAEC etc.. Database structure was designed

Erodibility of waste (Loess) soils from construction sites under water and wind erosional forces.

Science.gov (United States)

Tanner, Smadar; Katra, Itzhak; Argaman, Eli; Ben-Hur, Meni

2018-03-01

Excess soils from construction sites (waste soils) become a problem when exposed to soil erosion by water or wind. Understanding waste soil erodibility can contribute to its proper reuse for various surface applications. The general objective of the study was to provide a better understanding of the effects of soil properties on erodibility of waste soils excavated from various depths in a semiarid region under rainfall and wind erosive forces. Soil samples excavated from the topsoil (0-0.3m) and subsoil layers (0.3-0.9 and >1m depths) were subjected to simulated rainfall and wind. Under rainfall erosive forces, the subsoils were more erodible than the topsoil, in contrast to the results obtained under wind erosive forces. Exchangeable sodium percentage was the main factor controlling soil erodibility (K i ) under rainfall, and a significant logarithmic regression line was found between these two parameters. In addition, a significant, linear regression was found between K i and slaking values for the studied soil samples, suggesting that the former can be predicted from the latter. Soil erodibility under wind erosion force was controlled mainly by the dry aggregate characteristics (mean weight diameter and aggregate density): their higher values in the subsoil layers resulted in lower soil erodibility compared to the topsoil. Copyright © 2017 Elsevier B.V. All rights reserved.

Radiographic features of appendiceal colic in children

International Nuclear Information System (INIS)

Schisgall, R.M.

1986-01-01

The concept of appendiceal colic was introduced in 1980 to explain the common problem of recurrent crampy abdominal pain (RAP) in children. Children with appendiceal colic often have inspissated casts of stool as foreign bodies of the appendix. The radiographic findings of 115 children operated upon for appendiceal colic have been reviewed. The radiographic features of this syndrom have included: filling defects of the appendix (83% incidence of inspissated casts of stool within the appendix); partial filling of the appendix (44% incidence of fecal casts); retained barium behind 72 h (92% incidence of fecal casts blocking egress of barium); non-visualization of the appendix (42% incidence of fecal casts); and distention of the appendix (100% incidence of fecal casts). The correlation of radiographic and operative findings will be presented. A rational approach to the radiographic workup of a child with RAP will be presented. (orig.)

Computed tomography of appendiceal mucocele and peritoneal pseudomyxoma

International Nuclear Information System (INIS)

Lund, G.; Lien, H.H.

1982-01-01

Peritoneal pseudomyxoma is a colloidal growth, which develops on the peritoneum, often secondary to an ovarian tumor or mucocele of the appendix. The conventional radiographic findings of appendiceal mucocele were described by Akerlund, and the CT-pseudomyxoma have been reported by Seshul and Coulam. The present case illustrates the CT-findings of an appendiceal mucocele as well as the complicating peritoneal pseudomyxoma. (orig.)

Bladder metastases of appendiceal mucinous adenocarcinoma: a case presentation

Directory of Open Access Journals (Sweden)

Giusti Guido

2010-02-01

Full Text Available Abstract Background Appendiceal adenocarcinoma is rare with a frequency of 0.08% of all surgically removed appendices. Few cases of appendiceal carcinoma infiltrating the bladder wall for spatial contiguity have been documented. Case Presentation A case is reported of a 45-years old woman with mucinous cystadenocarcinoma of the appendix with bladder metastasis. Although ultrasonography and voided urinary cytology were negative, abdomen computed tomography (CT scan and cystoscopy and subsequent pathological examination revealed a mass exclusively located in the anterior wall of the bladder. Histopathology of the transurethral bladder resection revealed a bladder adenocarcinoma [6 cm (at the maximum diameter × 2,5 cm; approximate weight: 10 gr] with focal mucinous aspects penetrating the muscle and perivisceral fat. Laparotomy evidenced the presence of a solid mass of the appendix (2,5 cm × 3 cm × 2 cm extending to the loco-regional lymph nodes. Appendectomy and right hemicolectomy, linfoadenectomy and partial cystectomy were performed. The subsequent pathological examination revealed a mucinous cystadenocarcinoma of the appendix with metastatic cells colonising the anterior bladder wall and several colic lymph nodes. Conclusions The rarity of the appendiceal carcinoma invading the urinary bladder and its usual involvement of nearest organs and the posterior bladder wall, led us to describe this case which demonstrates the ability of the appendiceal cancer to metastasize different regions of urinary bladder.

Bladder metastases of appendiceal mucinous adenocarcinoma: a case presentation

International Nuclear Information System (INIS)

Taverna, Gianluigi; Graziotti, Pierpaolo; Corinti, Matteo; Colombo, Piergiuseppe; Grizzi, Fabio; Severo, Mauro; Piccinelli, Alessando; Giusti, Guido; Benetti, Alessio; Zucali, Paolo A

2010-01-01

Appendiceal adenocarcinoma is rare with a frequency of 0.08% of all surgically removed appendices. Few cases of appendiceal carcinoma infiltrating the bladder wall for spatial contiguity have been documented. A case is reported of a 45-years old woman with mucinous cystadenocarcinoma of the appendix with bladder metastasis. Although ultrasonography and voided urinary cytology were negative, abdomen computed tomography (CT) scan and cystoscopy and subsequent pathological examination revealed a mass exclusively located in the anterior wall of the bladder. Histopathology of the transurethral bladder resection revealed a bladder adenocarcinoma [6 cm (at the maximum diameter) × 2,5 cm; approximate weight: 10 gr] with focal mucinous aspects penetrating the muscle and perivisceral fat. Laparotomy evidenced the presence of a solid mass of the appendix (2,5 cm × 3 cm × 2 cm) extending to the loco-regional lymph nodes. Appendectomy and right hemicolectomy, linfoadenectomy and partial cystectomy were performed. The subsequent pathological examination revealed a mucinous cystadenocarcinoma of the appendix with metastatic cells colonising the anterior bladder wall and several colic lymph nodes. The rarity of the appendiceal carcinoma invading the urinary bladder and its usual involvement of nearest organs and the posterior bladder wall, led us to describe this case which demonstrates the ability of the appendiceal cancer to metastasize different regions of urinary bladder

I Got Them Dust Bowl Blues: Wind Erosion in the Music of the Southern Great Plains

Science.gov (United States)

Lee, J. A.

2017-12-01

This paper deals with the role of wind erosion and blowing dust on the music of the Dust Bowl region, a portion of the southern Great Plains of the United States. A defining characteristic of the region is dust storms, and in the 1930s, severe dust storms created dramatic images that came to symbolize all of the economic, social and environmental hardships suffered by the people during the 1930s. The music of the time, by Woody Guthrie and others, suggested that the region was being destroyed, never to recover. The region was resilient, however, and in recent decades, dust has been depicted in songs either as an adversity to be endured or simply as a normal part of life in the area. It may be that blowing dust has become a defining characteristic of the region because of a somewhat warped sense of pride in living in an often-difficult environment.

Active Anti-erosion Protection Strategy in Tamarisk (Tamarix aphylla)

Science.gov (United States)

Han, Zhiwu; Yin, Wei; Zhang, Junqiu; Niu, Shichao; Ren, Luquan

2013-12-01

Plants have numerous active protection strategies for adapting to complex and severe environments. These strategies provide endless inspiration for extending the service life of materials and machines. Tamarisk (Tamarix aphylla), a tree that thrives in raging sandstorm regions, has adapted to blustery conditions by evolving extremely effective and robust erosion resistant characteristics. However, the relationships among its surface cracks, internal histology and biomechanics, such as cracks, rings, cells, elasticity modulus and growth stress, which account for its erosion resistance, remain unclear. This present study reveals that the directionally eccentric growth rings of tamarisk, which are attributed to reduced stress and accelerated cell division, promote the formation of surface cracks. The windward rings are more extensive than the leeward side rings. The windward surfaces are more prone to cracks, which improves erosion resistance. Our data provide insight into the active protection strategy of the tamarisk against wind-sand erosion.

Estimation model of soil freeze-thaw erosion in Silingco watershed wetland of Northern Tibet.

Science.gov (United States)

Kong, Bo; Yu, Huan

2013-01-01

The freeze-thaw (FT) erosion is a type of soil erosion like water erosion and wind erosion. Limited by many factors, the grading evaluation of soil FT erosion quantities is not well studied. Based on the comprehensive analysis of the evaluation indices of soil FT erosion, we for the first time utilized the sensitivity of microwave remote sensing technology to soil moisture for identification of FT state. We established an estimation model suitable to evaluate the soil FT erosion quantity in Silingco watershed wetland of Northern Tibet using weighted summation method of six impact factors including the annual FT cycle days, average diurnal FT phase-changed water content, average annual precipitation, slope, aspect, and vegetation coverage. Finally, with the support of GIS, we classified soil FT erosion quantity in Silingco watershed wetland. The results showed that soil FT erosion are distributed in broad areas of Silingco watershed wetland. Different soil FT erosions with different intensities have evidently different spatial and geographical distributions.

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices. [Appendices only

Energy Technology Data Exchange (ETDEWEB)

Liverman, James L.

1977-09-01

Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant. (LK)

Cerebral Metastasis from a Previously Undiagnosed Appendiceal Adenocarcinoma

Directory of Open Access Journals (Sweden)

Antonio Biroli

2012-01-01

Full Text Available Brain metastases arise in 10%–40% of all cancer patients. Up to one third of the patients do not have previous cancer history. We report a case of a 67-years-old male patient who presented with confusion, tremor, and apraxia. A brain MRI revealed an isolated right temporal lobe lesion. A thorax-abdomen-pelvis CT scan showed no primary lesion. The patient underwent a craniotomy with gross-total resection. Histopathology revealed an intestinal-type adenocarcinoma. A colonoscopy found no primary lesion, but a PET-CT scan showed elevated FDG uptake in the appendiceal nodule. A right hemicolectomy was performed, and the specimen showed a moderately differentiated mucinous appendiceal adenocarcinoma. Whole brain radiotherapy was administrated. A subsequent thorax-abdomen CT scan revealed multiple lung and hepatic metastasis. Seven months later, the patient died of disease progression. In cases of undiagnosed primary lesions, patients present in better general condition, but overall survival does not change. Eventual identification of the primary tumor does not affect survival. PET/CT might be a helpful tool in detecting lesions of the appendiceal region. To the best of our knowledge, such a case was never reported in the literature, and an appendiceal malignancy should be suspected in patients with brain metastasis from an undiagnosed primary tumor.

Environmental assessment of remedial action at the Lakeview Uranium Mill Tailings Site, Lakeview, Oregon: Volume 2, Appendices

International Nuclear Information System (INIS)

1985-04-01

This document assesses and compares the environmental impacts of various alternatives for remedial action at the Lakeview uranium mill tailings site located one mile north of Lakeview, Oregon. The site covers 256 acres and contains 30 acres of tailings, 69 acres of evaporation ponds, and 25 acres of windblown materials. Remedial actions must be performed in accordance with standards and with the concurrence of the Nuclear Regulatory Commission. Three alternatives have been addressed in this document. The first alternative (the proposed action) is relocation of all contaminated materials to the Collins Ranch site. The contaminated materials would be consolidated into an embankment constructed partially below grade and covered with radon protection and erosion protection covers. A second alternative would relocate the tailings to the Flynn Ranch site and dispose of the contaminated materials in a slightly below grade embankment. A radon protection and erosion protection cover system would also be installed. The no-action alternative is also assessed. Stabilization in place is not considered due to potential seismic and geothermal hazards associated with the current tailings site, and the inability to meet EPA standards. Volume 2 contains 11 appendices

Appendiceal pathology at the time of oophorectomy for ovarian neoplasms.

Science.gov (United States)

Timofeev, Julia; Galgano, Mary T; Stoler, Mark H; Lachance, Jason A; Modesitt, Susan C; Jazaeri, Amir A

2010-12-01

To investigate the prevalence of appendiceal pathology in women undergoing surgery for a suspected ovarian neoplasm and the predictive value of intraoperative findings to determine the need for appendectomy at the time of surgery. Retrospective analysis of patients who underwent oophorectomy and appendectomy during the same surgical procedures at the University of Virginia Health System from 1992 to 2007. Observations were stratified based on the nature (benign, borderline, or malignant) and histology (serous compared with mucinous) of the ovarian neoplasm, frozen compared with final pathological diagnosis, and the gross appearance of the appendix. Among the 191 patients identified, frozen section was consistent with seven mucinous and 35 serous carcinomas, 16 serous and 33 mucinous borderline tumors, 71 mucinous and serous cystadenomas, and 29 cases of suspected metastatic tumor from a gastrointestinal primary. The highest rates of coexisting appendiceal pathology were associated with serous ovarian cancers (94.4% of grossly abnormal and 35.3% of normal appendices) and ovarian tumors suspected to be of primary gastrointestinal origin (83.3% grossly abnormal and 60.0% normal appendices harbored coexisting mucinous neoplasms). Linear regression analysis revealed that appearance of the appendix and frozen section diagnosis of the ovarian pathology were statistically significant predictors of coexisting appendiceal pathology, but the latter was more important. The prevalence of coexisting, clinically significant appendiceal pathology is low with a frozen section diagnosis of serous or mucinous cystadenoma. Appendectomy is recommended when frozen section diagnosis is mucinous or serous ovarian carcinoma, borderline tumor or metastatic carcinoma of suspected gastrointestinal origin.

Dust records in the Pleistocene sediments of Fraser Island: palaeoclimatic reconstruction of wind erosion over the last 600 ka

International Nuclear Information System (INIS)

Longmore, M.E.; McTainsh, G.H.

1997-01-01

Full text: Pleistocene lake sediments from a relic perched freshwater lake on Fraser Island have been found to date back to ca.600 ka using U/Th analysis of the organics. This sequence is one of the three longest terrestrial records of environmental change in Australia and the contained evidence of vegetation, fire and lake level changes (Longmore and Heijnis, 1996) and is an invaluable contribution to palaeoclimatic reconstruction. A younger sequence, dated by conventional radiocarbon analysis, has 6.5 m of continuous organic sedimentation from ca. 30 ka to the present. The last 8.5 ka has been analysed in detail, showing a mid-Holocene 'dry' period (Longmore, 1996). Continental aeolian dust from extreme wind erosional events has been measured in modern atmospheres (McTainsh, 1989; Knight et al., 1995) and deep sea cores (Hesse, 1994), but the terrestrial record of wind erosion during the Pleistocene is sparse. We will report on a pilot project to determine the presence of aeolian dust from extreme wind erosional events in the past in the sediments of Fraser Island lakes. Due to the highly weathered, well-sorted, siliceous nature of the dune sands forming the Island and the highly organic nature of the lake sediments (80-95% LOI), these are some of the few terrestrial sequences that permit separation of aeolian dust from local catchment materials. In the future, oxygen isotope and XRD analysis of the extracted dust will allow the most likely source of the entrained material to be determined and thus provide further evidence as to the wind regime during the last 600ka and 30ka respectively. The separation of dust from these terrestrial sequences is a major achievement and potentially may make a significant contribution to global palaeoclimatic models

Report on demonstrative research on photovoltaic power generation system in Myanmar. Appendices

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

With an objective of installation and demonstrative operation in Myanmar of a power generation system combining a small-scale photovoltaic power generation system, a wind power generation system, and a diesel generator, research and development is being made under a six year plan starting in 1999 and ending in 2004. This paper compiles the appendices related thereto. Collected for the climatic observation are the insolation data and wind velocity data in Chaungthar, and the insolation graph in both of Chaungthar and Lethokekone. Furthermore, materials for selection and decision on the installation location, and design materials for a hybrid power generation system were collected. Collected for procurement, construction, and installation of devices and facilities include test data for the diesel generator, drawings for the power generation control panel, test operation report, bill of lading for the diesel generator, a completion certificate of the diesel generator building, photographs of the building, a certificate of completion of installation of the diesel generator, photographs taken during the installation work, a certificate of completion of power transmission cable installation, photographs of the installation works, and the operation manual for the diesel engine. (NEDO)

Normal patterns of 18F-FDG appendiceal uptake in children

Energy Technology Data Exchange (ETDEWEB)

Reavey, Hamilton E. [Emory University, Department of Radiology and Imaging Sciences, Division of Nuclear Medicine Molecular Imaging, Atlanta, GA (United States); Alazraki, Adina L.; Simoneaux, Stephen F. [Emory University, Department of Radiology and Imaging Sciences, Division of Pediatric Imaging, Children' s Healthcare of Atlanta at Egleston, Atlanta, GA (United States)

2014-04-15

Prior to interpreting PET/CT, it is crucial to understand the normal biodistribution of fluorodeoxyglucose (FDG). It is also important to realize that the normal biodistribution can vary between adults and children. Although many studies have defined normal patterns of pediatric FDG uptake in structures like the thymus, brown fat and bone marrow, patterns of normal pediatric bowel activity, specifically uptake within the appendix, have not been well described. Active lymphoid tissue has increased FDG uptake when compared with inactive tissue. Since children have more active lymphoid tissue than adults, and because the appendix contains aggregated lymphoid tissue, we postulated that appendiceal uptake may be increased in pediatric patients. To define the normal level of appendiceal FDG activity in children by evaluating a series of consecutive FDG PET/CT scans performed for other indications. After obtaining IRB approval, we retrospectively reviewed 128 consecutive whole-body pediatric FDG PET/CT examinations obtained for a variety of clinical indications. CT scans on which the appendix could not be visualized were excluded from analysis. CT scans on which the appendix could be visualized were evaluated for underlying appendiceal pathology. Studies with appendiceal or periappendiceal pathology by CT criteria were excluded. A region of interest (ROI) was placed over a portion of each appendix and appendiceal maximum standardized uptake value (SUVmax) was calculated. If an adjacent loop of bowel activity interfered with accurate measurements of the appendix SUVmax, the scan was excluded from the analysis. A chart review was performed on patients with elevated appendiceal SUVmax values to ensure that the patients did not have clinical symptomatology suggestive of acute appendicitis. When the appendix or a portion of the appendix could be visualized and accurately measured, the SUVmax was determined. SUVmax of the appendix was compared to the SUVmax of normal liver and

Acute abdominal pain presenting as a rare appendiceal duplication: a case report

Directory of Open Access Journals (Sweden)

Mahmood Ali

2012-03-01

Full Text Available Abstract Introduction Appendiceal duplication is a rare anomaly that can manifest as right lower quadrant pain. There are several variations described for this condition. We recommend aggressive operative management should this anatomical variation present in the presence of acute appendicitis. Case presentation We report the case of a 15-year-old African American girl who presented to our hospital with right lower quadrant pain and was subsequently found to have appendiceal duplication. Conclusion There are two categorical systems that have described and stratified appendiceal duplication. Both classification systems have been outlined and referenced in this case report. A computed tomography scan has been included to provide a visual aid to help identify true vermiform appendiceal duplication. The presence of this anatomical abnormality is not a reason for surgical intervention; however, should this be found in the setting of acute appendicitis, aggressive resection of both appendices is mandatory.

Chronic appendicitis and complete appendiceal invagination: UC, CT and MRI findings

International Nuclear Information System (INIS)

Diaz, Gabriel; Seehaus, Alberto; Ocantos, Jorge; Diaz, Claudia; Coccaro, Nicolas; Piccioni, Hector

2003-01-01

The appendiceal intussusception is a rare entity. Usually there is a predisposing factor such as a tumor, mucocele, etc. We report the case of a 61 years old female patient, with recurrent abdominal pain, localized in the right lower quadrant. We performed different diagnostic imaging exams including: double-contrast barium enema, enteroclysis, ultrasonography, computed tomography and magnetic resonance. After endoscopy a surgical procedure removed the appendix. The pathological anatomy confirmed the diagnosis of an appendiceal intussusception, complicated with a chronic inflammatory process. Appendiceal intussusception and chronic appendicitis are infrequent; it is even more uncommon the association of both entities. In addition, it was not found a predisposing cause to intussusception. For the reasons described above, we conclude that this case is an unusual presentation of appendiceal intussusception, not previously reported. (author)

Vegetation in drylands: Effects on wind flow and aeolian sediment transport

Science.gov (United States)

Drylands are characterised by patchy vegetation, erodible surfaces and erosive aeolian processes. Empirical and modelling studies have shown that vegetation elements provide drag on the overlying airflow, thus affecting wind velocity profiles and altering erosive dynamics on desert surfaces. However...

[Species-associated differences in foliage-root coupling soil-reinforcement and anti-erosion].

Science.gov (United States)

Liu, Fu-quan; Liu, Jing; Nao, Min; Yao, Xi-jun; Zheng, Yong-gang; Li, You-fang; Su, Yu; Wang, Chen-jia

2015-02-01

This paper took four kinds of common soil and water conservation plants of the study area, Caragana microphylla, Salix psammophila, Artemisia sphaerocephala and Hippophae rhamnides at ages of 4 as the research object. Thirteen indicators, i.e., single shrub to reduce wind velocity ration, shelterbelt reducing wind velocity ration, community reducing wind velocity ration, taproot tensile strength, representative root constitutive properties, representative root elasticity modulus, lateral root branch tensile strength, accumulative surface area, root-soil interface sheer strength, interface friction coefficient, accumulative root length, root-soil composite cohesive, root-soil composite equivalent friction angle, reflecting the characteristics of windbreak and roots, were chose to evaluate the differences of foliage-root coupling soil-reinforcement and anti-erosion among four kinds of plants by analytic hierarchy process (AHP) under the condition of spring gale and summer rainstorm, respectively. The results showed the anti-erosion index of foliage-root coupling was in the sequence of S. psammophila (0.841) > C. microphylla (0.454) > A. sphaerocephala (-0.466) > H. rhamnides (-0.829) in spring gale, and C. microphylla (0.841) > S. psammophila (0. 474) > A. sphaerocephala (-0.470) > H. rhamnides (-0.844) in summer rainstorm. S. psammophila could be regarded as one of the most important windbreak and anti-erosion species, while C. microphylla could be the most valuable soil and water conservation plant for the study area.

Wear Resistance Performance of Conventional and Non-Conventional Wind Turbine Blades with TiN Nano-Coating

Directory of Open Access Journals (Sweden)

Muhammad Hasibul Hasan

2017-09-01

Full Text Available Efficiency and durability are critical issues that affect widely-adopted aerofoil-power generator as a sustainable source of electrical power. Even though high wind power density can be achieved; installing wind turbines in desert condition has difficulties including thermal variation, high turbulence and sand storms. Sand blasting on turbine blade surface at high velocities causes erosion resulting turbine efficiency drop. Damage-induced erosion phenomena and aeroelastic performance of the blades needed to be investigated. Suitable coating may prevent erosion to a great extent. A numerical investigation of erosion on NACA 4412 wind turbine blade has been performed using commercial computational fluid dynamics software ANSYS FLUENT 14.5 release. Discrete phase model (DPM has been used for modelling multi-phase flow of air and sand particles over the turbine blade. Governing equations have been solved by finite volume method (FVM. Conventional 30-70% glass fibre resin and non-conventional jute fibre composite have been used as turbine blade material. Sand particles of  diameter have been injected from 20, 30, 45, 60 and 90 degree angles at 500C temperature. Erosion rate, wall shear stress and strain rate have been calculated for different wind velocities and impingement angles. Simulation results for higher velocities deviate from the results observed at lower wind velocities. In simulation, erosion rate is highest for impingement angle at low wind velocities, which has been validated by experiment with a mean absolute error (MAE of 5.56%. Erosion rate and wall shear stress are higher on jute composite fibre than glass fibre resin. Developed shear stress on wind turbine blade surface is highest for  impingement angle at all velocities. On the other hand, exerted pressure on turbine blade surface is found highest for 9  angle of attack. Experimental results, with or without Titanium nitride(TiN nano-coating, also revealed that surface roughness

Quantification Of Erosion Rates Of Agriculturally Used Soils By Artificial

Science.gov (United States)

Jha, Abhinand

2010-05-01

0.0.1 1. Introduction to soil erosion measurement by radionuclides Soil erosion by water, wind and tillage affects both agriculture and the natural environment. Studying this phenomenon would be one of the advancements in science. Soil erosion occurs worldwide and since the last two decades it has been a main topic of discussion all over the world. The use of environmental radionuclides such as 90Sr, 137Cs to study medium term soil erosion (40 yrs) started in the early 1990's. Using these new techniques better knowledge about erosion can be gained and this knowledge can be implemented for erosion risk management. The erosion and sedimentation study by using man-made and natural radioisotopes is a key technique, which has developed over the past 30 years. Fallout 137Cs and Cosmogenic 7Be are radionuclides that have been used to provide independent measurements of soil-erosion and sediment-deposition rates and patterns [1] [2] [3] [4]. Erosion measurements using radionuclides 137Cs, 7Be Caesium-137 from atmospheric nuclear-weapons tests in the 1950s and 1960s (Fig.1) is a unique tracer of erosion and sedimentation, since there are no natural sources of 137Cs. Unique events such as the Chernobyl accident in April 1986 caused regional dispersal of 137Cs that affects the total global deposition budget. This yearly pattern of fallout can be used to develop a chronology of deposition horizons in lakes, reservoirs, and floodplains. 137Cs can be easily measured by gamma spectroscopy. Using 137Cs is a fast and cheap method to study erosion-deposition processes compared to the traditional methods like silt bags. PIC Figure 1: Global 137Cs fallout (Modified from SAAS Bulletin 353, Part E, DDR, 1986) When 137Cs, 7Be reach the soil surface by wet and dry deposition, they are quickly and strongly adsorbed by ion exchange and are essentially non exchangeable in most environments. Each radionuclide is distributed differently in the soil because of differences in half-lives (30 yrs

New perspectives on the soil erosion-soil quality relationship

International Nuclear Information System (INIS)

Pennock, D.J.

1998-01-01

The redistribution of soil has a profound impact on its quality (defined as its ability to function within its ecosystem and within adjacent ecosystems) and ultimately on its productivity for crop growth. The application of 137 Cs-redistribution techniques to the study of erosion has yielded major new insights into the soil erosion-soil quality relationship. In highly mechanized agricultural systems, tillage erosion can be the dominant cause of soil redistribution; in other agroecosystems, wind and water erosion dominate. Each causal factor results in characteristic landscape-scale patterns of redistribution. In landscapes dominated by tillage redistribution, highest losses occur in shoulder positions (those with convex downslope curvatures); in water-erosion-dominated landscapes, highest losses occur where slope gradient and length are at a maximum. Major impacts occur through the loss of organically-enriched surface material and through the incorporation of possibly yield-limiting subsoils into the rooting zone of the soil column. The potential impact of surface soil losses and concomitant subsoil incorporation on productivity may be assessed by examining the pedological nature of the affected soils and their position in the landscape. The development of sound conservation policies requires that the soil erosion-quality relationship be rigorously examined in the full range of pedogenic environments, and future applications of the 137 Cs technique hold considerable promise for providing this comprehensive global database. (author)

Soil physical properties affecting soil erosion in tropical soils

International Nuclear Information System (INIS)

Lobo Lujan, D.

2004-01-01

The total vegetated land area of the earth is about 11,500 hectare. Of this, about 12% is in South America. Of this, about 14% is degraded area. Water erosion, chemical degradation, wind erosion, and physical degradation have been reported as main types of degradation. In South America water erosion is a major process for soil degradation. Nevertheless, water erosion can be a consequence of degradation of the soil structure, especially the functional attributes of soil pores to transmit and retain water, and to facilitate root growth. Climate, soil and topographic characteristics determine runoff and erosion potential from agricultural lands. The main factors causing soil erosion can be divided into three groups: Energy factors: rainfall erosivity, runoff volume, wind strength, relief, slope angle, slope length; Protection factors: population density, plant cover, amenity value (pressure for use) and land management; and resistance factors: soil erodibility, infiltration capacity and soil management. The degree of soil erosion in a particular climatic zone, with particular soils, land use and socioeconomic conditions, will always result from a combination of the above mentioned factors. It is not easy to isolate a single factor. However, the soil physical properties that determine the soil erosion process, because the deterioration of soil physical properties is manifested through interrelated problems of surface sealing, crusting, soil compaction, poor drainage, impeded root growth, excessive runoff and accelerated erosion. When an unprotected soil surface is exposed to the direct impact of raindrops it can produce different responses: Production of smaller aggregates, dispersed particles, particles in suspension and translocation and deposition of particles. When this has occurred, the material is reorganized at the location into a surface seal. Aggregate breakdown under rainfall depends on soil strength and a certain threshold kinetic energy is needed to start

Sonographic study about differential diagnosis between acute appendicitis and non-appendicitis in appendices of borderline diameter

International Nuclear Information System (INIS)

Chung, Hwan Hoon; Kim, Yun Hwan; Kim, Hong Won; Park, Seung Cheol; Lee, Eun Jeong; Chung, Kyoo Byung; Suh, Won Hyuck

2000-01-01

To find out the sonographic criteria which can be effectively used to differentiate acute appendicitis from non-appendicitis in patients with appendices with borderline diameter(5-8 mm). Sixteen patients diagnosed as acute appendicitis, another 16 patients diagnosed as non-appendicitis were included in this study. They complained of RLQ pain and their appendices measured 5-8 mm in diameter on sonogram. Features such as appendiceal wall thickness, presence or absence of air in appendiceal lumen, movability of tip of the appendix, compressibility of the appendix were evaluated on gray-scale sonogram and thereafter, presence or absence of color flow in the wall of the appendix was evaluated on color Doppler sonogram. Thickness of appendiceal wall is 2.98 ± 0.77 mm in acute appendicitis group and 1.73 ± 0.44 mm in non-appendicitis group (p<0.05). When 2.5 mm thickness of appendiceal wall is applied for diagnosis of acute appendicitis, sensitivity is 81.3%, specificity is 87.5% and accuracy is 84.4%. With absence of air in appendiceal lumen, sensitivity is 93.8%, specificity is 68.8% and accuracy is 81.3%. With absence of movability of appendiceal tip, sensitivity is 87.5%, specificity is 50% and accuracy is 68.8%. With absence of compressibility of the appendix, sensitivity is 100%, specificity is 31.3% and accuracy is 65.6%. With color flow in appendiceal wall, sensitivity is 81.3%, specificity is 62.5% and accuracy is 71.9%. The above mentioned criteria show statistically significant difference between acute appendicitis and non-appendicitis groups (p<0.05). When the diameter of the appendix measures 5-8 mm on sonogram, evaluation of thickness of appendiceal wall, air in appendiceal lumen, movability of tip, compressibility and color flow in the wall will be helpful to diagnose the acute appendicitis with confidence.

Research reactor core conversion guidebook. V. 4: Fuels (Appendices I-K)

International Nuclear Information System (INIS)

1992-04-01

Volume 4 consists of detailed Appendices I-K, which contain useful information on the properties, irradiation testing, and specifications and inspection procedures for fuels with reduced uranium enrichments. Summaries of these appendices can be found in Chapters 9-11 of Volume 1 of this guidebook. Refs, figs, tabs and samples

Uranium milling: Draft generic environmental impact statement: Volume 2, Appendices

International Nuclear Information System (INIS)

1979-04-01

This volume contains appendices supporting the discussions in Volume 1. In some cases, the appendices expound upon arguments developed in the main document; in other cases, supplementary material considered to be relevant but not presented in Volume 1 is included. A third category encompasses reprinting of pertinent documents felt to be necessary for a comprehensive presentation of the current situation, e.g., Public Law 95-604

Erosion Testing of Coatings for V-22 Aircraft Applications

Directory of Open Access Journals (Sweden)

G. Y. Richardson

2003-01-01

Full Text Available High-velocity (183 m/sec sand erosion tests in a wind tunnel were conducted to evaluate developmental coatings from three separate companies under funding by the Navy's phase I small business innovative research program. The purpose of the coatings was to address a particular problem the V-22 tilt-rotor aircraft (Osprey was having with regard to ingestion of sand particles by a titanium impeller that was associated with the aircraft's environmental control system. The three coatings that were deposited on titanium substrates and erosion-tested included (1 SixCy/DLC multilayers deposited by chemical vapor deposition (CVD; (2 WC/TaC/TiC processed by electrospark deposition; and (3 polymer ceramic mixtures applied by means of an aqueous synthesis. The erosion test results are presented; they provided the basis for assessing the suitability of some of these coatings for the intended application.

Runoff erosion

OpenAIRE

Evelpidou, Niki (Ed.); Cordier, Stephane (Ed.); Merino, Agustin (Ed.); Figueiredo, Tomás de (Ed.); Centeri, Csaba (Ed.)

2013-01-01

Table of Contents PART I – THEORY OF RUNOFF EROSION CHAPTER 1 - RUNOFF EROSION – THE MECHANISMS CHAPTER 2 - LARGE SCALE APPROACHES OF RUNOFF EROSION CHAPTER 3 - MEASURING PRESENT RUNOFF EROSION CHAPTER 4 - MODELLING RUNOFF EROSION CHAPTER 5 - RUNOFF EROSION AND HUMAN SOCIETIES: THE INFLUENCE OF LAND USE AND MANAGEMENT PRACTICES ON SOIL EROSION PART II - CASE STUDIES CASE STUDIES – INTRODUCTION: RUNOFF EROSION IN MEDITERRANEAN AREA CASE STUDY 1: Soil Erosion Risk...

2008 wind farm submission requirements

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-05-01

Wind turbines used to generate electricity can have important visual, environmental and amenity impacts depending on their location. Planning can contribute to the provision of renewable energy by enabling wind energy development in appropriate locations in a manner that appropriately balances their environmental, social and economic benefits with any demonstrated visual, environmental and amenity impacts. The County of Bruce, Ontario and member municipalities are attempting to balance these matters in favour of an overall net community benefit. Planning applications need to include sufficient information and explanation to allow the approval authorities to come to a sound and timely decision, in order to facilitate a viable wind energy industry. This document outlined the County of Bruce application requirements in order to assist in the design and siting of proposed wind energy facilities and in preparing planning applications. The County of Bruce official plan and policies for large wind energy conversion systems (LWECS) were presented. Submissions requirements include an environmental screening report; a federal environmental assessment clearance; a prime agricultural land justification report; a general project description; turbine specifications; noise evaluation; shadow flicker calculations; visual effect modelling; NAV Canada/Transport Canada clearance; grid connections and routing; project staging; overshadowing study; electromagnetic interference study; turbine foundation drawings; and an environmental management plan. Other requirements include lot level maps; project area maps; sensitive receptor table; shadow flicker; stage 2 archaeological study; type certification; statement of planning policy conformity; and a submission checklist. 6 refs., 1 tab., 3 appendices.

Extra-appendiceal findings in pediatric abdominal CT for suspected appendicitis

Energy Technology Data Exchange (ETDEWEB)

Halverson, Mark; Delgado, Jorge; Mahboubi, Soroosh [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

2014-07-15

Much has been written regarding the incidence, types, importance and management of abdominal CT incidental findings in adults, but there is a paucity of literature on incidental findings in children. We sought to determine the prevalence and characteristics of extra-appendiceal and incidental findings in pediatric abdominal CT performed for suspected appendicitis. A retrospective review was performed of abdominal CT for suspected appendicitis in a pediatric emergency department from July 2010 to June 2012. Extra-appendiceal findings were recorded. Any subsequent imaging was noted. Extra-appendiceal findings were divided into incidental findings of doubtful clinical significance, alternative diagnostic findings potentially providing a diagnosis other than appendicitis explaining the symptoms, and incidental findings that were abnormalities requiring clinical correlation and sometimes requiring further evaluation but not likely related to the patient symptoms. One hundred sixty-five children had abdominal CT for suspected appendicitis. Seventy-seven extra-appendiceal findings were found in 57 (34.5%) patients. Most findings (64 of 77) were discovered in children who did not have appendicitis. Forty-one of these findings (53%) could potentially help explain the patient's symptoms, while 30 of the findings (39%) were abnormalities that were unlikely to be related to the symptoms but required clinical correlation and sometimes further work-up. Six of the findings (8%) had doubtful or no clinical significance. Extra-appendiceal findings are common in children who undergo abdominal CT in the setting of suspected appendicitis. A significant percentage of these patients have findings that help explain their symptoms. Knowledge of the types and prevalence of these findings may help radiologists in the planning and interpretation of CT examinations in this patient population. (orig.)

Cometary X-rays : solar wind charge exchange in cometary atmospheres

NARCIS (Netherlands)

Bodewits, Dennis

2007-01-01

The interaction of the solar wind with the planets and the interstellar medium is of key importance for the evolution of our solar system. The interaction with Earth's atmosphere is best known for the northern light. In case of Mars, the interaction with the solar wind might have lead to the erosion

Transport of biologically important nutrients by wind in an eroding cold desert

Science.gov (United States)

Sankey, Joel B.; Germino, Matthew J.; Benner, Shawn G.; Glenn, Nancy F.; Hoover, Amber N.

2012-01-01

Wind erosion following fire is an important landscape process that can result in the redistribution of ecologically important soil resources. In this study we evaluated the potential for a fire patch in a desert shrubland to serve as a source of biologically important nutrients to the adjacent, downwind, unburned ecosystem. We analyzed nutrient concentrations (P, K, Ca, Mg, Cu, Fe, Mn, Al) in wind-transported sediments, and soils from burned and adjacent unburned surfaces, collected during the first to second growing seasons after a wildfire that burned in 2007 in Idaho, USA in sagebrush steppe; a type of cold desert shrubland. We also evaluated the timing of potential wind erosion events and weather conditions that might have contributed to nutrient availability in downwind shrubland. Findings indicated that post-fire wind erosion resulted in an important, but transient, addition of nutrients on the downwind shrubland. Aeolian sediments from the burned area were enriched relative to both the up- and down-wind soil and indicated the potential for a fertilization effect through the deposition of the nutrient-enriched sediment during the first, but not second, summer after wildfire. Weather conditions that could have produced nutrient transport events might have provided increased soil moisture necessary to make nutrients accessible for plants in the desert environment. Wind transport of nutrients following fire is likely important in the sagebrush steppe as it could contribute to pulses of resource availability that might, for example, affect plant species differently depending on their phenology, and nutrient- and water-use requirements.

Mars power system concept definition study. Volume 2: Appendices

Science.gov (United States)

Littman, Franklin D.

1994-01-01

This report documents the work performed by Rockwell International's Rocketdyne Division on NASA Contract No. NAS3-25808 (Task Order No. 16) entitled 'Mars Power System Definition Study'. This work was performed for NASA's Lewis Research Center (LeRC). The report is divided into two volumes as follows: Volume 1 - Study Results; and Volume 2 - Appendices. The results of the power system characterization studies, operations studies, and technology evaluations are summarized in Volume 1. The appendices include complete, standalone technology development plans for each candidate power system that was investigated.

Bioengineering Technology to Control River Soil Erosion using Vetiver (Vetiveria Zizaniodes)

Science.gov (United States)

Sriwati, M.; Pallu, S.; Selintung, M.; Lopa, R.

2018-04-01

Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock or dissolved material from one location on the earth’s crust, and then transport it away to another location. Bioengineering is an attempt to maximise the use of vegetation components along riverbanks to cope with landslides and erosion of river cliffs and another riverbank damage. This study aims to analyze the bioengineering of Vetiver as a surface layer for soil erosion control using slope of 100, 200, and 300. This study is conducted with 3 variations of rain intensity (I), at 103 mm/hour, 107 mm/hour, and 130 mm/hour by using rainfall simulator tool. In addition, the USLE (Universal Soil Loss Equation) method is used in order to measure the rate of soil erosion. In this study, there are few USLE model parameters were used such as rainfall erosivity factor, soil erodibility factor, length-loss slope and stepness factor, cover management factor, and support practise factor. The results demonstrated that average of reduction of erosion rate using Vetiver, under 3 various rainfalls, namely rainfall intensity 103 mm/hr had reduced 84.971%, rainfall intensity 107 mm/hr had reduced 86.583 %, rainfall intensity 130 mm/hr had reduced 65.851%.

Impact of wind turbines on birdlife

International Nuclear Information System (INIS)

Benner, J.H.B.; Berkhuizen, J.C.; De Graaff, R.J.; Postma, A.D.; Hendriks, J.H.W.

1993-05-01

An overview of wind energy programmes is presented, as well as an analysis of recent studies on the title subject and data on the attitude of nature conservation organisations both from the USA and Europe. The studies were analyzed for legitimacy of assumptions and validity of the conclusions. Most of the wind energy programs and all European studies deal with bird kills and disturbance in coastal areas. The number of victims per turbine per year in this type of area appears to be acceptable. The disturbing effect of wind turbines on breeding birds appears to be negligible. The disturbance of resting and migrating birds by wind turbines however is reasonably clear. As a result of international concern several sites have been designated where siting of wind turbines is prohibited. Well known examples are wetlands of international importance (Ramsar-convention) and European Community Special Protection Areas. Major concern among conservationists is the location of many valuable and vulnerable environmental resources outside the protected areas. Negative attitudes towards wind energy projects are not particularly due to avian considerations, but rather to a general objective to protect landscapes and habitats, undisturbed by human infrastructures and disturbance. It is concluded that all new locations for wind energy projects should be weighed on the disturbance aspect. Reference data for such a weigh are available for coastal areas, although the impact on local migration between feeding grounds and high water refugee areas needs further research. Future research is also needed for application of wind energy both on off-shore locations, grasslands and farmlands. Wind energy developers and conservationists should have a close contact in order to establish consensus on how to deal with remaining uncertainties. 7 figs., 9 tabs., 5 appendices, 37 refs

Impact of wind turbines on birdlife

Energy Technology Data Exchange (ETDEWEB)

Benner, J H.B.; Berkhuizen, J C; De Graaff, R J; Postma, A D [Consultants on Energy and Environment CEA, Rotterdam (Netherlands); Hendriks, J H.W. [Rijksuniversiteit Leiden (Netherlands)

1993-05-01

An overview of wind energy programmes is presented, as well as an analysis of recent studies on the title subject and data on the attitude of nature conservation organisations both from the USA and Europe. The studies were analyzed for legitimacy of assumptions and validity of the conclusions. Most of the wind energy programs and all European studies deal with bird kills and disturbance in coastal areas. The number of victims per turbine per year in this type of area appears to be acceptable. The disturbing effect of wind turbines on breeding birds appears to be negligible. The disturbance of resting and migrating birds by wind turbines however is reasonably clear. As a result of international concern several sites have been designated where siting of wind turbines is prohibited. Well known examples are wetlands of international importance (Ramsar-convention) and European Community Special Protection Areas. Major concern among conservationists is the location of many valuable and vulnerable environmental resources outside the protected areas. Negative attitudes towards wind energy projects are not particularly due to avian considerations, but rather to a general objective to protect landscapes and habitats, undisturbed by human infrastructures and disturbance. It is concluded that all new locations for wind energy projects should be weighed on the disturbance aspect. Reference data for such a weigh are available for coastal areas, although the impact on local migration between feeding grounds and high water refugee areas needs further research. Future research is also needed for application of wind energy both on off-shore locations, grasslands and farmlands. Wind energy developers and conservationists should have a close contact in order to establish consensus on how to deal with remaining uncertainties. 7 figs., 9 tabs., 5 appendices, 37 refs.

Wind uplift of radioactive dust from the ground

International Nuclear Information System (INIS)

Makhon'ko, K.P.

1992-01-01

Near nuclear power plants the recontamination of the atmosphere near the ground becomes dangerous, if a radioactive zone has formed at the site. Wind can easily carry toxic dust from the polluted territory of neighboring industrial enterprises. Moreover, wind erosion of the soil during the summer or transport of radioactive snow by a snowstorm during the winter can displace the boundaries of the contaminated radioactive zone. In Russia the investigation of wind pickup of radioactive dust from the ground began after a radiation accident occurred at a storage facility in the Southern Urals in 1957, as a result of which a contaminated zone formed in the area. Since the direct mechanism of detachment of dust particles from the ground is not important in studying the results of the raising of radioactive dust into the atmosphere by wind, the authors do not distinguish between wind pickup and wind erosion, and the entire process wind pickup of radioactivity from the ground. After the radiation accident at the Chernobyl nuclear power plant a new generation of investigators began to study wind pickup of radioactive dust from the ground, and the process under consideration was sometimes referred to as wind uplift. The intensity of the process of wind pickup of radioactive dust from the ground is characterized by the wind pickup coefficient α, which is the coefficient of proportionality between the upward flux Q of radioactivity from the ground and the density A of radioactive contamination of the ground: α = Q/A. Physically, the coefficient α is the upward flux of the impurity from the ground with unit contamination density, i.e., the intensity of dust contamination or the fraction of radioactivity picked up by the wind from the ground per unit time. The greatest difficulty in determining α experimentally under dusty conditions is measuring correctly the upward radioactivity flux Q. The author discusses three methods for determining this quantity

Agriculture’s Soil Conservation Programs Miss Full Potential in the Fight against Soil Erosion.

Science.gov (United States)

1983-11-28

Soil Loss Equation ( USLE ) and Wind Erosion Equation can be used with a reasonable degree of accuracy. It is the intention of ASCS to expand VC/SL to...HD-R37 495 AGRICULTURE’S SOIL CONSERVATION PROGRAMS MISS FULL i/i POTENTIAL IN THE FIGHT.(U) GENERAL ACCOUNTING OFFICE WASHINGTON DC RESOURCES...GENERAL Report To The Congress OF THE UNITED STATES Agriculture’s Soil Conservation Programs Miss Full Potential In The Fight Against Soil Erosion

Evaluation of compost blankets for erosion control from disturbed lands.

Science.gov (United States)

Bhattarai, Rabin; Kalita, Prasanta K; Yatsu, Shotaro; Howard, Heidi R; Svendsen, Niels G

2011-03-01

Soil erosion due to water and wind results in the loss of valuable top soil and causes land degradation and environmental quality problems. Site specific best management practices (BMP) are needed to curb erosion and sediment control and in turn, increase productivity of lands and sustain environmental quality. The aim of this study was to investigate the effectiveness of three different types of biodegradable erosion control blankets- fine compost, mulch, and 50-50 mixture of compost and mulch, for soil erosion control under field and laboratory-scale experiments. Quantitative analysis was conducted by comparing the sediment load in the runoff collected from sloped and tilled plots in the field and in the laboratory with the erosion control blankets. The field plots had an average slope of 3.5% and experiments were conducted under natural rainfall conditions, while the laboratory experiments were conducted at 4, 8 and 16% slopes under simulated rainfall conditions. Results obtained from the field experiments indicated that the 50-50 mixture of compost and mulch provides the best erosion control measures as compared to using either the compost or the mulch blanket alone. Laboratory results under simulated rains indicated that both mulch cover and the 50-50 mixture of mulch and compost cover provided better erosion control measures compared to using the compost alone. Although these results indicate that the 50-50 mixtures and the mulch in laboratory experiments are the best measures among the three erosion control blankets, all three types of blankets provide very effective erosion control measures from bare-soil surface. Results of this study can be used in controlling erosion and sediment from disturbed lands with compost mulch application. Testing different mixture ratios and types of mulch and composts, and their efficiencies in retaining various soil nutrients may provide more quantitative data for developing erosion control plans. Copyright © 2010 Elsevier

Single-incision laparoscopic cecectomy for low-grade appendiceal mucinous neoplasm after laparoscopic rectectomy

Science.gov (United States)

Fujino, Shiki; Miyoshi, Norikatsu; Noura, Shingo; Shingai, Tatsushi; Tomita, Yasuhiko; Ohue, Masayuki; Yano, Masahiko

2014-01-01

In this case report, we discuss single-incision laparoscopic cecectomy for low-grade appendiceal neoplasm after laparoscopic anterior resection for rectal cancer. The optimal surgical therapy for low-grade appendiceal neoplasm is controversial; currently, the options include appendectomy, cecectomy, right hemicolectomy, and open or laparoscopic surgery. Due to the risk of pseudomyxoma peritonei, complete resection without rupture is necessary. We have encountered 5 cases of low-grade appendiceal neoplasm and all 5 patients had no lymph node metastasis. We chose the appendectomy or cecectomy without lymph node dissection if preoperative imaging studies did not suspect malignancy. In the present case, we performed cecectomy without lymph node dissection by single-incision laparoscopic surgery (SILS), which is reported to be a reduced port surgery associated with decreased invasiveness and patient stress compared with conventional laparoscopic surgery. We are confident that SILS is a feasible alternative to traditional surgical procedures for borderline tumors, such as low-grade appendiceal neoplasms. PMID:24868331

RECONSTRUCTING THE SOLAR WIND FROM ITS EARLY HISTORY TO CURRENT EPOCH

Energy Technology Data Exchange (ETDEWEB)

Airapetian, Vladimir S.; Usmanov, Arcadi V., E-mail: vladimir.airapetian@nasa.gov, E-mail: avusmanov@gmail.com [NASA Goddard Space Flight Center, Greenbelt, MD (United States)

2016-02-01

Stellar winds from active solar-type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties except for mass-loss rates cannot be directly derived from observations. We employed a three-dimensional magnetohydrodynamic Alfvén wave driven solar wind model, ALF3D, to reconstruct the solar wind parameters including the mass-loss rate, terminal velocity, and wind temperature at 0.7, 2, and 4.65 Gyr. Our model treats the wind thermal electrons, protons, and pickup protons as separate fluids and incorporates turbulence transport, eddy viscosity, turbulent resistivity, and turbulent heating to properly describe proton and electron temperatures of the solar wind. To study the evolution of the solar wind, we specified three input model parameters, the plasma density, Alfvén wave amplitude, and the strength of the dipole magnetic field at the wind base for each of three solar wind evolution models that are consistent with observational constrains. Our model results show that the velocity of the paleo solar wind was twice as fast, ∼50 times denser and 2 times hotter at 1 AU in the Sun's early history at 0.7 Gyr. The theoretical calculations of mass-loss rate appear to be in agreement with the empirically derived values for stars of various ages. These results can provide realistic constraints for wind dynamic pressures on magnetospheres of (exo)planets around the young Sun and other active stars, which is crucial in realistic assessment of the Joule heating of their ionospheres and corresponding effects of atmospheric erosion.

RECONSTRUCTING THE SOLAR WIND FROM ITS EARLY HISTORY TO CURRENT EPOCH

International Nuclear Information System (INIS)

Airapetian, Vladimir S.; Usmanov, Arcadi V.

2016-01-01

Stellar winds from active solar-type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties except for mass-loss rates cannot be directly derived from observations. We employed a three-dimensional magnetohydrodynamic Alfvén wave driven solar wind model, ALF3D, to reconstruct the solar wind parameters including the mass-loss rate, terminal velocity, and wind temperature at 0.7, 2, and 4.65 Gyr. Our model treats the wind thermal electrons, protons, and pickup protons as separate fluids and incorporates turbulence transport, eddy viscosity, turbulent resistivity, and turbulent heating to properly describe proton and electron temperatures of the solar wind. To study the evolution of the solar wind, we specified three input model parameters, the plasma density, Alfvén wave amplitude, and the strength of the dipole magnetic field at the wind base for each of three solar wind evolution models that are consistent with observational constrains. Our model results show that the velocity of the paleo solar wind was twice as fast, ∼50 times denser and 2 times hotter at 1 AU in the Sun's early history at 0.7 Gyr. The theoretical calculations of mass-loss rate appear to be in agreement with the empirically derived values for stars of various ages. These results can provide realistic constraints for wind dynamic pressures on magnetospheres of (exo)planets around the young Sun and other active stars, which is crucial in realistic assessment of the Joule heating of their ionospheres and corresponding effects of atmospheric erosion

Final Technical Report - Kotzebue Wind Power Project - Volume II

Energy Technology Data Exchange (ETDEWEB)

Rana Zucchi, Global Energy Concepts, LLC; Brad Reeve, Kotzebue Electric Association; DOE Project Officer - Doug Hooker

2007-10-31

The Kotzebue Wind Power Project is a joint undertaking of the U.S. Department of Energy (DOE); Kotzebue Electric Association (KEA); and the Alaska Energy Authority (AEA). The goal of the project is to develop, construct, and operate a wind power plant interconnected to a small isolated utility grid in an arctic climate in Northwest Alaska. The primary objective of KEA’s wind energy program is to bring more affordable electricity and jobs to remote Alaskan communities. DOE funding has allowed KEA to develop a multi-faceted approach to meet these objectives that includes wind project planning and development, technology transfer, and community outreach. The first wind turbines were installed in the summer of 1997 and the newest turbines were installed in the spring of 2007. The total installed capacity of the KEA wind power project is 1.16 MW with a total of 17 turbines rated between 65 kW and 100 kW. The operation of the wind power plant has resulted in a wind penetration on the utility system in excess of 35% during periods of low loads. This document and referenced attachments are presented as the final technical report for the U.S. Department of Energy (DOE) grant agreement DE-FG36-97GO10199. Interim deliverables previously submitted are also referenced within this document and where reasonable to do so, specific sections are incorporated in the report or attached as appendices.

Hyperbilirubinemia as a predictor for appendiceal perforation

DEFF Research Database (Denmark)

Burcharth, J; Pommergaard, H C; Rosenberg, J

2013-01-01

Delayed or wrong diagnosis in patients with appendicitis can result in perforation and consequently increased morbidity and mortality. Serum bilirubin may be a useful marker for appendiceal perforation. The purpose of this systematic review was to evaluate studies investigating elevated serum...

A large source of dust missing in Particulate Matter emission inventories? Wind erosion of post-fire landscapes

Directory of Open Access Journals (Sweden)

N.S. Wagenbrenner

2017-02-01

Full Text Available Wind erosion of soils burned by wildfire contributes substantial particulate matter (PM in the form of dust to the atmosphere, but the magnitude of this dust source is largely unknown. It is important to accurately quantify dust emissions because they can impact human health, degrade visibility, exacerbate dust-on-snow issues (including snowmelt timing, snow chemistry, and avalanche danger, and affect ecological and biogeochemical cycles, precipitation regimes, and the Earth’s radiation budget. We used a novel modeling approach in which local-scale winds were used to drive a high-resolution dust emission model parameterized for burned soils to provide a first estimate of post-fire PM emissions. The dust emission model was parameterized with dust flux measurements from a 2010 fire scar. Here we present a case study to demonstrate the ability of the modeling framework to capture the onset and dynamics of a post-fire dust event and then use the modeling framework to estimate PM emissions from burn scars left by wildfires in U.S. western sagebrush landscapes during 2012. Modeled emissions from 1.2 million ha of burned soil totaled 32.1 Tg (11.7–352 Tg of dust as PM10 and 12.8 Tg (4.68–141 Tg as PM2.5. Despite the relatively large uncertainties in these estimates and a number of underlying assumptions, these first estimates of annual post-fire dust emissions suggest that post-fire PM emissions could substantially increase current annual PM estimates in the U.S. National Emissions Inventory during high fire activity years. Given the potential for post-fire scars to be a large source of PM, further on-site PM flux measurements are needed to improve emission parameterizations and constrain these first estimates.

Appendiceal Mucocele in an Elderly Patient: How Much Surgery

Directory of Open Access Journals (Sweden)

C. Kim-Fuchs

2011-09-01

Full Text Available Appendiceal mucoceles are rare cystic lesions with an incidence of 0.3–0.7% of all appendectomies. They are divided into four subgroups according to their histology. Even though the symptoms may vary – depending on the level of complication – from right lower quadrant pain, signs of intussusception, gastrointestinal bleeding to an acute abdomen with sepsis, most mucoceles are asymptomatic and found incidentally. We present the case of a 70-year-old patient with an incidentally found appendiceal mucocele. He was seen at the hospital for backache. The CT scan showed a vertebral fracture and a 7-cm appendiceal mass. A preoperative colonoscopy displayed several synchronous adenomas in the transverse and left colon with high-grade dysplasia. In order to lower the cancer risk of this patient, we performed a subtotal colectomy. The appendiceal mass showed no histopathological evidence of malignancy and no sign of perforation. The follow-up was therefore limited to 2 months. In this case, appendectomy would have been sufficient to treat the mucocele alone. The synchronous high-grade dysplastic adenomas were detected in the preoperative colonoscopy and determined the therapeutic approach. Generally, in the presence of positive lymph nodes, a right colectomy is the treatment of choice. In the histological presence of mucinous peritoneal carcinomatosis, cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is indicated. In conclusion, mucoceles of the appendix are detected with high sensitivity by CT scan. If there is no evidence of synchronous tumor preoperatively and no peritoneal spillage, invasion or positive sentinel lymph nodes during surgery, a mucocele is adequately treated by appendectomy.

Low-grade appendiceal mucinous neoplasm mimicking an adnexal mass.

Science.gov (United States)

Cristian, Daniel Alin; Grama, Florin Andrei; Becheanu, Gabriel; Pop, Anamaria; Popa, Ileana; Şurlin, Valeriu; Stănilescu, Sorin; Bratu, Ana Magdalena; Burcoş, Traean

2015-01-01

We present a rare case of malignant epithelial neoplasm of the appendix, an uncommon disorder encountered in clinical practice, which poses a variety of diagnostic and therapeutic challenges. We report a particular case in which the appendix was abnormally located in the pelvis, mimicking an adnexal mass. Therefore, it was difficult to make the preoperative diagnosis on clinical examination, imaging studies and laboratory tests and we discovered the lesion during the diagnostic laparoscopy. No lymphadenopathy or mucinous ascites were found. The case was completely handled via the laparoscopic approach keeping the appendix intact during the operation. The frozen section, the detailed histopathology overview as well as multiple immunostaining with a complex panel of markers report diagnosed a low-grade appendiceal mucinous neoplasm (LAMN) with no invasion of the wall. No adjuvant therapy was considered needed. At a one-year follow-up oncological assessment, the patient was free of disease. In women with cystic mass in the right iliac fossa an appendiceal mucocele should be considered in the differential diagnosis. Laparoscopic appendectomy can represent an adequate operation for the appendiceal mucinous neoplasm if the histological report is clear and surgical precautionary measures are taken.

The possible hindrance of a 8 MW wind farm along the Zuidermeerdijk in the Noordoostpolder, Netherlands, for birds

International Nuclear Information System (INIS)

Van den Bergh, L.M.J.; Spaans, A.L.

1993-01-01

The title farm comprises 16 three-bladed 500 kW wind turbines. Hindrance of wind turbines are collisions with the wind turbines and in the wake behind the blades and loss or disintegration of the natural habitat because of the presence of the wind turbines (aspect of disturbance). The title study is focused on counting the number of collision bird victims per year, and analyzing the disturbance effects on hibernating and foraging birds. It appeared that almost 150 to more than 1500 birds will collide with one of the 16 wind turbines. A few hundred tufted ducks, some tens of pochard and some tens of wild ducks per kilometre of the wind farm will leave their natural habitat. Based on the results it is concluded that the dike area between kilometre marker 32.5 and kilometre marker 35.5 is the most suitable area for a wind turbine array along the Zuidermeerdijk in between Schokkerhaven and Ketelbrug, both Netherlands. 3 figs., 5 tabs., 2 appendices, 33 refs

An Assessment of the Impact of Urbanization on Soil Erosion in Inner Mongolia.

Science.gov (United States)

Wang, Li-Yan; Xiao, Yi; Rao, En-Ming; Jiang, Ling; Xiao, Yang; Ouyang, Zhi-Yun

2018-03-19

Inner Mongolia, an autonomous region of the People's Republic of China, has experienced severe soil erosion following a period of rapid economic development and urbanization. To investigate how urbanization has influenced the extent of soil erosion in Inner Mongolia, we used urbanization and soil erosion data from 2000 through 2010 to determine the relationship between urbanization and soil erosion patterns. Two empirical equations-the Revised Universal Soil Loss Equation (RUSLE) and the Revised Wind Erosion Equation (RWEQ)-were used to estimate the intensity of soil erosion, and we performed backward linear regression to model how it changed with greater urbanization. There was an apparent increase in the rate of urbanization and a decrease in the area affected by soil erosion in 2010 compared to the corresponding values for 2000. The urban population stood at 11.32 million in 2010, which represented a 16.47% increase over that in 2000. The area affected by soil erosion in 2000 totaled 704,817 km², yet it had decreased to 674,135 km² by 2010. However, a path of modest urban development (rural-urban mitigation) and reasonable industrial structuring (the development of GDP-2) may partially reduce urbanization's ecological pressure and thus indirectly reduce the threat of soil erosion to human security. Therefore, to better control soil erosion in Inner Mongolia during the process of urbanization, the current model of economic development should be modified to improve the eco-efficiency of urbanization, while also promoting new modes of urbanization that are environmentally sustainable, cost-effective, and conserve limited resources.

An Assessment of the Impact of Urbanization on Soil Erosion in Inner Mongolia

Directory of Open Access Journals (Sweden)

Li-Yan Wang

2018-03-01

Full Text Available Inner Mongolia, an autonomous region of the People’s Republic of China, has experienced severe soil erosion following a period of rapid economic development and urbanization. To investigate how urbanization has influenced the extent of soil erosion in Inner Mongolia, we used urbanization and soil erosion data from 2000 through 2010 to determine the relationship between urbanization and soil erosion patterns. Two empirical equations—the Revised Universal Soil Loss Equation (RUSLE and the Revised Wind Erosion Equation (RWEQ—were used to estimate the intensity of soil erosion, and we performed backward linear regression to model how it changed with greater urbanization. There was an apparent increase in the rate of urbanization and a decrease in the area affected by soil erosion in 2010 compared to the corresponding values for 2000. The urban population stood at 11.32 million in 2010, which represented a 16.47% increase over that in 2000. The area affected by soil erosion in 2000 totaled 704,817 km2, yet it had decreased to 674,135 km2 by 2010. However, a path of modest urban development (rural–urban mitigation and reasonable industrial structuring (the development of GDP-2 may partially reduce urbanization’s ecological pressure and thus indirectly reduce the threat of soil erosion to human security. Therefore, to better control soil erosion in Inner Mongolia during the process of urbanization, the current model of economic development should be modified to improve the eco-efficiency of urbanization, while also promoting new modes of urbanization that are environmentally sustainable, cost-effective, and conserve limited resources.

Thermal erosion of a permafrost coastline: Improving process-based models using time-lapse photography

Science.gov (United States)

Wobus, C.; Anderson, R.; Overeem, I.; Matell, N.; Clow, G.; Urban, F.

2011-01-01

Coastal erosion rates locally exceeding 30 m y-1 have been documented along Alaska's Beaufort Sea coastline, and a number of studies suggest that these erosion rates have accelerated as a result of climate change. However, a lack of direct observational evidence has limited our progress in quantifying the specific processes that connect climate change to coastal erosion rates in the Arctic. In particular, while longer ice-free periods are likely to lead to both warmer surface waters and longer fetch, the relative roles of thermal and mechanical (wave) erosion in driving coastal retreat have not been comprehensively quantified. We focus on a permafrost coastline in the northern National Petroleum Reserve-Alaska (NPR-A), where coastal erosion rates have averaged 10-15 m y-1 over two years of direct monitoring. We take advantage of these extraordinary rates of coastal erosion to observe and quantify coastal erosion directly via time-lapse photography in combination with meteorological observations. Our observations indicate that the erosion of these bluffs is largely thermally driven, but that surface winds play a crucial role in exposing the frozen bluffs to the radiatively warmed seawater that drives melting of interstitial ice. To first order, erosion in this setting can be modeled using formulations developed to describe iceberg deterioration in the open ocean. These simple models provide a conceptual framework for evaluating how climate-induced changes in thermal and wave energy might influence future erosion rates in this setting.

Using REE tracers to measure sheet erosion changing to rill erosion

International Nuclear Information System (INIS)

Liu Puling; Xue Yazhou; Song Wei; Wang Mingyi; Ju Tongjun

2004-01-01

Rare Earth Elements (REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different rare earth elements of different soil depth across a slope in an indoor plot, two simulated rainfalls were applied to study the change of erosion type and the rill erosion process. The results indicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happens after rill erosion appears. Accumulated sheet and rill erosion amounts increase with the rainfalls time. The percentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of the rainfalls, the total rill erosion amounts are 4-5 times more than sheet erosion. In this paper, a new REE tracer method was used to quantitatively distinguish sheet and rill erosion amounts. The new REE tracer method should be useful to future studying of erosion processes on slope lands. (authors)

Shelter Index and a simple wind speed parameter to characterize vegetation control of sand transport threshold and Flu

Science.gov (United States)

Gillies, J. A.; Nield, J. M.; Nickling, W. G.; Furtak-Cole, E.

2014-12-01

Wind erosion and dust emissions occur in many dryland environments from a range of surfaces with different types and amounts of vegetation. Understanding how vegetation modulates these processes remains a research challenge. Here we present results from a study that examines the relationship between an index of shelter (SI=distance from a point to the nearest upwind vegetation/vegetation height) and particle threshold expressed as the ratio of wind speed measured at 0.45 times the mean plant height divided by the wind speed at 17 m when saltation commences, and saltation flux. The results are used to evaluate SI as a parameter to characterize the influence of vegetation on local winds and sediment transport conditions. Wind speed, wind direction, saltation activity and point saltation flux were measured at 35 locations in defined test areas (~13,000 m2) in two vegetation communities: mature streets of mesquite covered nebkhas and incipient nebkhas dominated by low mesquite plants. Measurement positions represent the most open areas, and hence those places most susceptible to wind erosion among the vegetation elements. Shelter index was calculated for each measurement position for each 10° wind direction bin using digital elevation models for each site acquired using terrestrial laser scanning. SI can show the susceptibility to wind erosion at different time scales, i.e., event, seasonal, or annual, but in a supply-limited system it can fail to define actual flux amounts due to a lack of knowledge of the distribution of sediment across the surface of interest with respect to the patterns of SI.

Main results from Risoe's wind-diesel programme 1984-1990

International Nuclear Information System (INIS)

Lundsager, P.; Christensen, C.J.

1991-12-01

The report presents the results of the wind-diesel work done in projects at Risoe National Laboratory during the years 1984-90, including important earlier publications as appendices. The partners in the original joint project were Risoe National Laboratory, Denmark, and Chalmers University of Technology, Sweden. Chalmers has constructed and laboratory tested an advanced wind-diesel-battery system with variable speed operation of the wind turbine, while Risoe has established a flexible and versatile wind-diesel test facility and field tested Chalmers system. As part of the subsequent EFP projects Risoe designed and constructed a simple wind-diesel system without storage, characterized by several innovative features. This concept was part of a ''simple wind-diesel systems strategy'', in which immediate cost-effectiveness is ensured by the simplicity and reliability of the design. Dynamic computer models were developed for system design and analysis purposes, and a general logistic computer model was developed for the determination of fuel savings and power supply capabilities for a number of system configurations. In addition to a considerable body of experience the main results of activities are: A versatile wind-diesel test facility and a proposed standard wind-diesel test procedure. Two wind-diesel systems at each end of the spectrum of configurations. Computer models for logistic and dynamic modelling. The two systems represent the very simple system concept, believed to be a presently economically optimal configuration, and the very sophisticated concept believed to be a future optimal configuration. (au) (6 tabs., 67 ills., 25 refs.)

Erosion-corrosion synergistics in the low erosion regime

International Nuclear Information System (INIS)

Corey, R.G.; Sethi, V.K.

1986-01-01

Many engineering alloys display good high temperature corrosion resistance. However, when they are used in corrosive environments where they are subjected to erosion also, the corrosion resistance has been adversely affected. The phenomenon known as erosion-corrosion is complex and requires detailed investigation of how the erosion and corrosion kinetics interact and compete. At the Kentucky Center for Energy Research Laboratory, an erosion-corrosion tester was used to perform erosion-oxidation tests on 2 1/4 Cr-1 Mo steel at 500-600 0 C using alumina abrasive at low velocities. The erosion-oxidation rate data and morphology of exposed surfaces are consistent with oxide chipping and fracturing being the mode of material loss

Post-wildfire soil erosion in the Mediterranean: Review and future research directions

Science.gov (United States)

Shakesby, R. A.

2011-04-01

Wildfires increased dramatically in frequency and extent in the European Mediterranean region from the 1960s, aided by a general warming and drying trend, but driven primarily by socio-economic changes, including rural depopulation, land abandonment and afforestation with flammable species. Published research into post-wildfire hydrology and soil erosion, beginning during the 1980s in Spain, has been followed by studies in other European Mediterranean countries together with Israel and has now attained a sufficiently large critical mass to warrant a major review. Although variations in climate, vegetation, soil, topography and fire severity cause differences in Mediterranean post-wildfire erosion, the long history of human landscape impact up to the present day is responsible for some its distinctive characteristics. This paper highlights these characteristics in reviewing wildfire impacts on hydrology, soil properties and soil erosion by water. The 'mosaic' nature of many Mediterranean landscapes (e.g. an intricate land-use pattern, abandoned terraces and tracks interrupting slopes) may explain sometimes conflicting post-fire hydrological and erosional responses at different sites and spatial scales. First-year post-wildfire soil losses at point- (average, 45-56 t ha - 1 ) and plot-scales (many Aspect is important, with more erosion reported for south- than north-facing slopes, which is attributed to greater fire frequency, slower vegetation recovery on the former and with soil characteristics more prone to erosion (e.g. lower aggregate stability). Post-fire wind erosion is a potentially important but largely neglected process. Gauging the degradational significance of wildfires has relied on comparison with unburnt land, but the focus for comparison should be switched to other agents of soil disturbance and/or currently poorly understood soil renewal rates. Human impact on land use and vegetation may alter expected effects (increased fire activity and post

Low-Grade Appendiceal Mucinous Neoplasm Involving the Endometrium and Presenting with Mucinous Vaginal Discharge.

Science.gov (United States)

Vavinskaya, Vera; Baumgartner, Joel M; Ko, Albert; Saenz, Cheryl C; Valasek, Mark A

2016-01-01

Primary appendiceal mucinous lesions are uncommon and represent a spectrum from nonneoplastic mucous retention cysts to invasive adenocarcinoma. Low-grade appendiceal mucinous neoplasms (LAMNs) represent an intermediate category on this spectrum and can be classified according to whether or not they are confined to the appendix. Although LAMNs are frequently confined to the appendix, they can also spread to the peritoneum and clinically progress as pseudomyxoma peritonei (i.e., mucinous ascites). Thus, the appropriate classification of appendiceal primary neoplasia is essential for prognosis and influences clinical management. In addition, the precise classification, management, and clinical outcome of patients with disseminated peritoneal disease remain controversial. Here, we report an unusual case of LAMN with pseudomyxoma peritonei that initially presented with mucinous and bloody vaginal discharge. Pathological evaluation revealed low-grade appendiceal mucinous neoplasm with secondary involvement of the peritoneum, ovaries, and endometrial surface. Therefore, LAMN should be considered in the differential diagnosis of mucinous vaginal discharge.

Low-Grade Appendiceal Mucinous Neoplasm Involving the Endometrium and Presenting with Mucinous Vaginal Discharge

Directory of Open Access Journals (Sweden)

Vera Vavinskaya

2016-01-01

Full Text Available Primary appendiceal mucinous lesions are uncommon and represent a spectrum from nonneoplastic mucous retention cysts to invasive adenocarcinoma. Low-grade appendiceal mucinous neoplasms (LAMNs represent an intermediate category on this spectrum and can be classified according to whether or not they are confined to the appendix. Although LAMNs are frequently confined to the appendix, they can also spread to the peritoneum and clinically progress as pseudomyxoma peritonei (i.e., mucinous ascites. Thus, the appropriate classification of appendiceal primary neoplasia is essential for prognosis and influences clinical management. In addition, the precise classification, management, and clinical outcome of patients with disseminated peritoneal disease remain controversial. Here, we report an unusual case of LAMN with pseudomyxoma peritonei that initially presented with mucinous and bloody vaginal discharge. Pathological evaluation revealed low-grade appendiceal mucinous neoplasm with secondary involvement of the peritoneum, ovaries, and endometrial surface. Therefore, LAMN should be considered in the differential diagnosis of mucinous vaginal discharge.

Process-based coastal erosion modeling for Drew Point (North Slope, Alaska)

Science.gov (United States)

Ravens, Thomas M.; Jones, Benjamin M.; Zhang, Jinlin; Arp, Christopher D.; Schmutz, Joel A.

2012-01-01

A predictive, coastal erosion/shoreline change model has been developed for a small coastal segment near Drew Point, Beaufort Sea, Alaska. This coastal setting has experienced a dramatic increase in erosion since the early 2000’s. The bluffs at this site are 3-4 m tall and consist of ice-wedge bounded blocks of fine-grained sediments cemented by ice-rich permafrost and capped with a thin organic layer. The bluffs are typically fronted by a narrow (∼ 5  m wide) beach or none at all. During a storm surge, the sea contacts the base of the bluff and a niche is formed through thermal and mechanical erosion. The niche grows both vertically and laterally and eventually undermines the bluff, leading to block failure or collapse. The fallen block is then eroded both thermally and mechanically by waves and currents, which must occur before a new niche forming episode may begin. The erosion model explicitly accounts for and integrates a number of these processes including: (1) storm surge generation resulting from wind and atmospheric forcing, (2) erosional niche growth resulting from wave-induced turbulent heat transfer and sediment transport (using the Kobayashi niche erosion model), and (3) thermal and mechanical erosion of the fallen block. The model was calibrated with historic shoreline change data for one time period (1979-2002), and validated with a later time period (2002-2007).

Canton hydroelectric project: feasibility study. Final report, appendices

Energy Technology Data Exchange (ETDEWEB)

1979-05-01

These appendices contain legal, environmental, regulatory, technical and economic information used in evaluating the feasibility of redeveloping the hydroelectric power generating facilities at the Upper and Lower Dams of the Farmington River at Collinsville, CT. (LCL)

The impacts of grazing land management on the wind erodibility of the Mulga Lands of western Queensland, Australia

Science.gov (United States)

An estimated 100 Mt of dust is eroded by wind from the Australian land surface each year. Wind erosion may be widespread across the arid and semi-arid rangelands, with impacts on soil nutrients, carbon and ecosystem services, human health, and climate. The susceptibility of landscapes to wind erosio...

1986 resource strategy technical appendices. Volume 2

International Nuclear Information System (INIS)

1986-01-01

The following appendices are included: Decision Analysis Model Documentation; WNP-1 and WNP-3 Preservation Cost Analysis; Regional Costs vs. Net Benefits; Supplemental Conservation Results; National Science Foundation (NSF) Definition of Research and Development; Research and Development: ''Short-Term'' Need and ''Long-Term'' Capability Building; and Value of Energy

[Responses of soil fauna to environment degeneration in the process of wind erosion desertification of Hulunbeir steppe].

Science.gov (United States)

Lü, Shi-Hai; Lu, Xin-Shi; Gao, Ji-Xi

2007-09-01

To reveal the relationships between soil fauna and soil environmental factors in the process of steppe desertification, field survey combined with laboratory analysis was made to study the community structure, population density and biodiversity of soil fauna, and their relationships with the changes of soil organic matter, hydrolysable nitrogen, available phosphorus and moisture contents and soil pH at different stages of desertification of Hulunbeir steppe. The soil faunal specimens collected belonged to 4 phyla, 6 classes and 12 orders. Nematoda was the only dominant group of medium- and small-sized soil fauna, occupying 94.3% of the total, while Coleoptera and Hemiptera were the dominant groups of large-sized soil fauna, with the amount of 79.7%. The group amount, population density, diversity, and evenness of soil fauna had an obvious decreasing trend with the aggravation of steppe desertification. At serious stage of desertification, soil fauna vanished completely. The population density of soil fauna in 0-20 cm soil layer had significant linear correlations with soil nutrients and moisture contents, soil pH, and litter mass, indicating that soil fauna had stronger sensibility to the changes of soil environmental factors in the process of wind erosion desertification of Hulunbeir steppe.

Superconductivity for Large Scale Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

2012-10-12

A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

A New Global Regression Analysis Method for the Prediction of Wind Tunnel Model Weight Corrections

Science.gov (United States)

Ulbrich, Norbert Manfred; Bridge, Thomas M.; Amaya, Max A.

2014-01-01

A new global regression analysis method is discussed that predicts wind tunnel model weight corrections for strain-gage balance loads during a wind tunnel test. The method determines corrections by combining "wind-on" model attitude measurements with least squares estimates of the model weight and center of gravity coordinates that are obtained from "wind-off" data points. The method treats the least squares fit of the model weight separate from the fit of the center of gravity coordinates. Therefore, it performs two fits of "wind- off" data points and uses the least squares estimator of the model weight as an input for the fit of the center of gravity coordinates. Explicit equations for the least squares estimators of the weight and center of gravity coordinates are derived that simplify the implementation of the method in the data system software of a wind tunnel. In addition, recommendations for sets of "wind-off" data points are made that take typical model support system constraints into account. Explicit equations of the confidence intervals on the model weight and center of gravity coordinates and two different error analyses of the model weight prediction are also discussed in the appendices of the paper.

A terminological matter: paragenesis, antigravitative erosion or antigravitational erosion ?

Directory of Open Access Journals (Sweden)

Pasini G.

2009-07-01

Full Text Available In the speleological literature three terms are utilized to designate the “ascending erosion”: paragenesis (= paragénésis, coined in1968, antigravitative erosion (= erosione antigravitativa, coined in 1966 and antigravitational erosion (wrong English translation ofthe Italian term erosione antigravitativa, utilized later on. The term paragenesis should be abandoned because of the priority of theterm erosione antigravitativa - on the ground of the “law of priority” – and because of its ambiguous etimology. On the other hand,the term antigravitational erosion should be forsaken in favour of the term antigravitative erosion, given the meaning that the termsgravitation and gravity have in Physics. Therefore, to designate the phenomenon of the “ascending erosion” there would be nothingleft but the term antigravitative erosion.The antigravitative erosion process and its recognizability are illustrated.Examples of caves with evident antigravitative erosion phenomena, developed in different karstifiable rocks and in several partsof the world, are given.It is recalled that the antigravitative erosion is a phenomenon well-known since 1942 and widely proven and supported, and that it isrelatively easy – in many cases - to recognize the antigravitative origin of karstic passages.It is stressed that the antigravitative erosion is an important phenomenon, exclusive of the karstic caves and unique in nature.

Modeling the fluid/soil interface erosion in the Hole Erosion Test

Directory of Open Access Journals (Sweden)

Kissi B.

2012-07-01

Full Text Available Soil erosion is a complex phenomenon which yields at its final stage to insidious fluid leakages under the hydraulic infrastructures known as piping and which are the main cause of their rupture. The Hole Erosion Test is commonly used to quantify the rate of piping erosion. In this work, The Hole Erosion Test is modelled by using Fluent software package. The aim is to predict the erosion rate of soil during the hole erosion test. The renormalization group theory – based k–ε turbulence model equations are used. This modelling makes it possible describing the effect of the clay concentration in flowing water on erosion. Unlike the usual one dimensional models, the proposed modelling shows that erosion is not uniform erosion along the hole length. In particular, the concentration of clay is found to increase noticeably the erosion rate.

National Wind Technology Center sitewide, Golden, CO: Environmental assessment

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-11-01

The National Renewable Energy Laboratory (NREL), the nation`s primary solar and renewable energy research laboratory, proposes to expand its wind technology research and development program activities at its National Wind Technology Center (NWTC) near Golden, Colorado. NWTC is an existing wind energy research facility operated by NREL for the US Department of Energy (DOE). Proposed activities include the construction and reuse of buildings and facilities, installation of up to 20 wind turbine test sites, improvements in infrastructure, and subsequent research activities, technology testing, and site operations. In addition to wind turbine test activities, NWTC may be used to support other NREL program activities and small-scale demonstration projects. This document assesses potential consequences to resources within the physical, biological, and human environment, including potential impacts to: air quality, geology and soils, water resources, biological resources, cultural and historic resources, socioeconomic resources, land use, visual resources, noise environment, hazardous materials and waste management, and health and safety conditions. Comment letters were received from several agencies in response to the scoping and predecisional draft reviews. The comments have been incorporated as appropriate into the document with full text of the letters contained in the Appendices. Additionally, information from the Rocky Flats Environmental Technology Site on going sitewide assessment of potential environmental impacts has been reviewed and discussed by representatives of both parties and incorporated into the document as appropriate.

National Wind Technology Center sitewide, Golden, CO: Environmental assessment

International Nuclear Information System (INIS)

1996-11-01

The National Renewable Energy Laboratory (NREL), the nation's primary solar and renewable energy research laboratory, proposes to expand its wind technology research and development program activities at its National Wind Technology Center (NWTC) near Golden, Colorado. NWTC is an existing wind energy research facility operated by NREL for the US Department of Energy (DOE). Proposed activities include the construction and reuse of buildings and facilities, installation of up to 20 wind turbine test sites, improvements in infrastructure, and subsequent research activities, technology testing, and site operations. In addition to wind turbine test activities, NWTC may be used to support other NREL program activities and small-scale demonstration projects. This document assesses potential consequences to resources within the physical, biological, and human environment, including potential impacts to: air quality, geology and soils, water resources, biological resources, cultural and historic resources, socioeconomic resources, land use, visual resources, noise environment, hazardous materials and waste management, and health and safety conditions. Comment letters were received from several agencies in response to the scoping and predecisional draft reviews. The comments have been incorporated as appropriate into the document with full text of the letters contained in the Appendices. Additionally, information from the Rocky Flats Environmental Technology Site on going sitewide assessment of potential environmental impacts has been reviewed and discussed by representatives of both parties and incorporated into the document as appropriate

ENDF6-transformation of the MENDL-2 and WIND transmutation libraries

International Nuclear Information System (INIS)

Koning, A.J.

1997-09-01

The MENDL (Medium Energy Nuclear Data library) and WIND (Waste Incineration Nuclear Data library) transmutation libraries have been transformed to the ENDF6-format. A drawback of the original form of these libraries was that they were not processable due to an alternative method to store the residual production cross sections. The new representation of the data is outlined. The transformed library has been checked with the ENDF6 preprocessing tools CHECKR, FIZCON and PSYCHE. In the process of transformation, several errors have been corrected. 5 refs., 3 appendices

ENDF6-transformation of the MENDL-2 and WIND transmutation libraries

Energy Technology Data Exchange (ETDEWEB)

Koning, A.J.

1997-09-01

The MENDL (Medium Energy Nuclear Data library) and WIND (Waste Incineration Nuclear Data library) transmutation libraries have been transformed to the ENDF6-format. A drawback of the original form of these libraries was that they were not processable due to an alternative method to store the residual production cross sections. The new representation of the data is outlined. The transformed library has been checked with the ENDF6 preprocessing tools CHECKR, FIZCON and PSYCHE. In the process of transformation, several errors have been corrected. 5 refs., 3 appendices.

Wind Wave Behavior in Fetch and Depth Limited Estuaries

Science.gov (United States)

Karimpour, Arash; Chen, Qin; Twilley, Robert R.

2017-01-01

Wetland dominated estuaries serve as one of the most productive natural ecosystems through their ecological, economic and cultural services, such as nursery grounds for fisheries, nutrient sequestration, and ecotourism. The ongoing deterioration of wetland ecosystems in many shallow estuaries raises concerns about the contributing erosive processes and their roles in restraining coastal restoration efforts. Given the combination of wetlands and shallow bays as landscape components that determine the function of estuaries, successful restoration strategies require knowledge of wind wave behavior in fetch and depth limited water as a critical design feature. We experimentally evaluate physics of wind wave growth in fetch and depth limited estuaries. We demonstrate that wave growth rate in shallow estuaries is a function of wind fetch to water depth ratio, which helps to develop a new set of parametric wave growth equations. We find that the final stage of wave growth in shallow estuaries can be presented by a product of water depth and wave number, whereby their product approaches 1.363 as either depth or wave energy increases. Suggested wave growth equations and their asymptotic constraints establish the magnitude of wave forces acting on wetland erosion that must be included in ecosystem restoration design.

2004 Power marketing program final EIS - final environmental impact statement. Volume 2 - appendices

International Nuclear Information System (INIS)

1997-02-01

This volume contains appendices to the Final Environmental Impact Statement (FEIS) for the Power Marketing Program proposal of the Western Area Power Administration. The FEIS identified peaking power scheduling as the environmentally preferred alternative, and presented the analysis of alternatives and environmental impacts. Sixteen appendices to the FEIS are included in this document. The appendices are: Statutory and Legal Framework; Sierra Nevada Region Customer Groups and Economic Regions; Renewable Technology Cost Information Matrix; Hydrological Assumptions; Recreation Resources; Archaeological and Historical Resources; Incremental Power Resources; Air Quality Regulatory Structure; Energy Generation; Stage Contents Relationships for Regulating Reservoirs; Power Costs; Socioeconomic Impacts; Projected Air Resource Impacts; Land use, Water Quality, and Solid Waste Impact Factors; Draft Environmental Impact Statement Comments and Responses, and Contractor Disclosure Statements. 21 figs., 24 tabs

Subseabed disposal program annual report, January-December 1980. Volume II. Appendices (principal investigator progress reports). Part 1

International Nuclear Information System (INIS)

Hinga, K.R.

1981-07-01

Volume II of the sixth annual report describing the progress and evaluating the status of the Subseabed Disposal Program contains the appendices referred to in Volume I, Summary and Status. Because of the length of Volume II, it has been split into two parts for publication purposes. Part 1 contains Appendices A-Q; Part 2 contains Appendices R-MM. Separate abstracts have been prepared for each appendix for inclusion in the Energy Data Base

Subseabed disposal program annual report, January-December 1980. Volume II. Appendices (principal investigator progress reports). Part 1

Energy Technology Data Exchange (ETDEWEB)

Hinga, K.R. (ed.)

1981-07-01

Volume II of the sixth annual report describing the progress and evaluating the status of the Subseabed Disposal Program contains the appendices referred to in Volume I, Summary and Status. Because of the length of Volume II, it has been split into two parts for publication purposes. Part 1 contains Appendices A-Q; Part 2 contains Appendices R-MM. Separate abstracts have been prepared for each appendix for inclusion in the Energy Data Base.

Appendiceal immunoglobulin G4-related disease mimicking appendiceal tumor or appendicitis: A case report

International Nuclear Information System (INIS)

Kim, Hyun Soo; Kang, Won Kyung; Chung, Dong Jin

2016-01-01

Immunoglobulin G4 (IgG4)-related disease is an autoimmune disease that forms tumorous lesions. Several cases involving various organs are reported, however, IgG4-related disease involving appendix has not been reported yet. In this report, we presented a case of IgG4-related disease of appendix, which raised a suspicion of appendiceal tumor or usual appendicitis and, therefore, led to unnecessary surgical resection. IgG4-related disease should be considered in the differential diagnosis for a mass-like swelling of the appendix, in order to avoid unnecessary surgery

Appendiceal immunoglobulin G4-related disease mimicking appendiceal tumor or appendicitis: A case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Soo; Kang, Won Kyung; Chung, Dong Jin [Yeouido St. Mary' s Hospital, The Catholic University of Korea, Seoul (Korea, Republic of)

2016-02-15

Immunoglobulin G4 (IgG4)-related disease is an autoimmune disease that forms tumorous lesions. Several cases involving various organs are reported, however, IgG4-related disease involving appendix has not been reported yet. In this report, we presented a case of IgG4-related disease of appendix, which raised a suspicion of appendiceal tumor or usual appendicitis and, therefore, led to unnecessary surgical resection. IgG4-related disease should be considered in the differential diagnosis for a mass-like swelling of the appendix, in order to avoid unnecessary surgery.

Numerical modelling of concentrated leak erosion during Hole Erosion Tests

OpenAIRE

Mercier, F.; Bonelli, S.; Golay, F.; Anselmet, F.; Philippe, P.; Borghi, R.

2015-01-01

This study focuses on the numerical modelling of concentrated leak erosion of a cohesive soil by a turbulent flow in axisymmetrical geometry, with application to the Hole Erosion Test (HET). The numerical model is based on adaptive remeshing of the water/soil interface to ensure accurate description of the mechanical phenomena occurring near the soil/water interface. The erosion law governing the interface motion is based on two erosion parameters: the critical shear stress and the erosion co...

INEL environmental characterization report. Volume III. Appendices E-H

International Nuclear Information System (INIS)

1984-09-01

This volume contains the following appendices: (1) INEL subsurface hydrology; (2) cultural resources assessment of two study areas on the INEL; (3) description of INEL facilities; and (4) effluent measurements and environmental monitoring programs

A Case of Appendiceal Adenocarcinoma with Clinical Benefit from FOLFOX and Bevacizumab

Directory of Open Access Journals (Sweden)

Erin D. Powell

2009-07-01

Full Text Available A 44-year-old woman presented with lower abdominal pain and bilateral ovarian masses on ultrasound. Exploratory laparotomy revealed extensive peritoneal and intra-abdominal disease and an abnormal appendix. Bilateral salpingo-oophorectomy, infracolic omentectomy, ileocolic resection and primary anastomosis were performed. Final pathology revealed a primary appendiceal adenocarcinoma, poorly differentiated, of signet ring cell type. CT scan postoperatively revealed gross residual disease. The patient was treated with FOLFOX chemotherapy combined with bevacizumab. Repeat CT scan showed a decrease in residual disease and the patient clinically improved. After her treatment has been continued for 13 months, she remains clinically well and her CT scan shows sustained disease stability. Disseminated appendiceal carcinoma is generally considered to be refractory to 5-FU-based chemotherapy and, to our knowledge, this is the first reported case of a patient with appendiceal adenocarcinoma demonstrating clinical benefit and sustained stability of disease with combination chemotherapy plus bevacizumab.

Linking rapid erosion of the Mekong River delta to human activities.

Science.gov (United States)

Anthony, Edward J; Brunier, Guillaume; Besset, Manon; Goichot, Marc; Dussouillez, Philippe; Nguyen, Van Lap

2015-10-08

As international concern for the survival of deltas grows, the Mekong River delta, the world's third largest delta, densely populated, considered as Southeast Asia's most important food basket, and rich in biodiversity at the world scale, is also increasingly affected by human activities and exposed to subsidence and coastal erosion. Several dams have been constructed upstream of the delta and many more are now planned. We quantify from high-resolution SPOT 5 satellite images large-scale shoreline erosion and land loss between 2003 and 2012 that now affect over 50% of the once strongly advancing >600 km-long delta shoreline. Erosion, with no identified change in the river's discharge and in wave and wind conditions over this recent period, is consistent with: (1) a reported significant decrease in coastal surface suspended sediment from the Mekong that may be linked to dam retention of its sediment, (2) large-scale commercial sand mining in the river and delta channels, and (3) subsidence due to groundwater extraction. Shoreline erosion is already responsible for displacement of coastal populations. It is an additional hazard to the integrity of this Asian mega delta now considered particularly vulnerable to accelerated subsidence and sea-level rise, and will be exacerbated by future hydropower dams.

Ice Forces on Offshore Wind Power Plants. Descriptions of mechanisms and recommendations for dimensioning; Islaster paa vindkraftverk till havs. Beskrivning av mekanismer och rekommendationer foer dimensionering

Energy Technology Data Exchange (ETDEWEB)

Bergdahl, Lars [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept of Water Environment Transport

2002-02-01

Mechanisms for ice-loads on off-shore wind power plants are described, The ice-loads are due to thermal expansion, water level variations, drifting ice and ice-reefing. Ice accretion is briefly treated. Ice instance, ice thickness, ice retention time, water level variations and stream velocities in Swedish waters are compiled. The main text deals with recommendations for dimensioning wind power plants at sea. In the appendices, a thorough review of the physical and mechanical properties of ice is presented.

Appendiceal Endometriosis: A case Report and Literature Review ...

African Journals Online (AJOL)

Appendiceal endometriosis is a very rare and usually asymptomatic condiction, but can result in severe complications such as intestinal perforation, massive gastrointestinal bleeding or intussusception. We report a case of endometriosis of the appendix presenting as acute appendicitis. The patient was a 36 year old ...

LiDAR-based 2D Localization and Mapping System using Elliptical Distance Correction Models for UAV Wind Turbine Blade Inspection

DEFF Research Database (Denmark)

Nikolov, Ivan Adriyanov; Madsen, Claus B.

2017-01-01

The wind energy sector faces a constant need for annual inspections of wind turbine blades for damage, erosion and cracks. These inspections are an important part of the wind turbine life cycle and can be very costly and hazardous to specialists. This has led to the use of automated drone inspect...

Shoosing the appropriate size wind turbine

Energy Technology Data Exchange (ETDEWEB)

Lynette, R. [FloWind Corp., San Rafael, CA (United States)

1996-12-31

Within the past several years, wind turbines rated at 400 kW and higher have been introduced into the market, and some manufacturers are developing machines rated at 750 - 1,000+ kW. This raises the question: What is the appropriate size for utility-grade wind turbines today? The answer depends upon the site where the machines will be used and the local conditions. The issues discussed in the paper are: (1) Site-Related (a) Visual, noise, erosion, television interference, interference with aviation (b) Siting efficiency (2) Logistics (a) Adequacy of roads and bridges to accept large vehicles (b) Availability and cost of cranes for erection and maintenance (c) Capability of local repair/overhauls (3) Cost Effectiveness (a) Capital costs (1) Wind Turbine (2) Infrastructure costs (b) Maintenance costs (4) Technical/Financial Risk. 1 fig., 1 tab.

Usefulness of measurement of the outer appendiceal diameter on abdominal computer tomography in the diagnosis of acute appendicitis

International Nuclear Information System (INIS)

Chisuwa, Hisanao; Tauchi, Katsunori; Mori, Shusuke; Kishimoto, Hirofumi; Koike, Hideo; Higuchi, Kayoko; Ohmori, Toshihiro; Miyazawa, Masahisa

2008-01-01

The purpose of this study was to evaluate the accuracy of our computer tomography (CT)-based protocol and the usefulness of measurement of the outer appendiceal diameter on CT in the diagnosis of acute appendicitis. Two-hundred thirty-nine consecutive patients with clinical diagnoses of acute appendicitis during the period from January 2002 to Jun 2004 were evaluated. The CT criterion of acute appendicitis was the outer appendiceal diameter of 6 mm or more, and/or other associated inflammatory changes. The histological criterion of acute appendicitis was the presentation of polymorphic granulocytes throughout the appendiceal wall. Of 239 patients, 235 underwent CT examination. Among 222 patients with appendectomy, 205 had histologically proven acute appendicitis. Of 200 patients who had the outer appendiceal diameter of 6 mm or more on CT, 193 had histologically proven acute appendicitis. The positive predictive value for diagnosing acute appendicitis was 92.3% in the surgery group, and 96.5% in the group that the outer appendiceal diameter was 6 mm or more on CT. The recurrence rate of acute appendicitis diagnosed by CT following conservative therapy was 35.3%, and was high (50%) in the group with the appendiceal diameter of at least 10 mm. CT is useful in the diagnosis for acute appendicitis. (author)

Economic evaluation of the annual cycle energy system (ACES). Final report. Volume III, appendices

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

This volume consists of seven appendices related to ACES, the first three of which are concerned with computer programs. The appendices are entitled: (A) ACESIM: Residential Program Listing; (B) Typical Inputs and Outputs of ACESIM; (C) CACESS: Commercial Building Program Listing; (D) Typical Weather-Year Selection Requirements; (E) Building Characteristics; (F) List of Major Variables Used in the Computer Programs; and (G) Bibliography. 79 references.

Remote-handled transuranic system assessment appendices. Volume 2

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

Volume 2 of this report contains six appendices to the report: Inventory and generation of remote-handled transuranic waste; Remote-handled transuranic waste site storage; Characterization of remote-handled transuranic waste; RH-TRU waste treatment alternatives system analysis; Packaging and transportation study; and Remote-handled transuranic waste disposal alternatives.

Remote-handled transuranic system assessment appendices. Volume 2

International Nuclear Information System (INIS)

1995-11-01

Volume 2 of this report contains six appendices to the report: Inventory and generation of remote-handled transuranic waste; Remote-handled transuranic waste site storage; Characterization of remote-handled transuranic waste; RH-TRU waste treatment alternatives system analysis; Packaging and transportation study; and Remote-handled transuranic waste disposal alternatives

The June 2016 Australian East Coast Low: Importance of Wave Direction for Coastal Erosion Assessment

Directory of Open Access Journals (Sweden)

Thomas R. Mortlock

2017-02-01

Full Text Available In June 2016, an unusual East Coast Low storm affected some 2000 km of the eastern seaboard of Australia bringing heavy rain, strong winds and powerful wave conditions. While wave heights offshore of Sydney were not exceptional, nearshore wave conditions were such that beaches experienced some of the worst erosion in 40 years. Hydrodynamic modelling of wave and current behaviour as well as contemporaneous sand transport shows the east to north-east storm wave direction to be the major determinant of erosion magnitude. This arises because of reduced energy attenuation across the continental shelf and the focussing of wave energy on coastal sections not equilibrated with such wave exposure under the prevailing south-easterly wave climate. Narrabeen–Collaroy, a well-known erosion hot spot on Sydney’s Northern Beaches, is shown to be particularly vulnerable to storms from this direction because the destructive erosion potential is amplified by the influence of the local embayment geometry. We demonstrate the magnified erosion response that occurs when there is bi-directionality between an extreme wave event and preceding modal conditions and the importance of considering wave direction in extreme value analyses.

Jabiluka project - Draft Environmental Impact Statement. Appendices

International Nuclear Information System (INIS)

1996-01-01

The Appendices provide various technical data in support of studies presented in the Main Report, including the guidelines for an EIS at Jabiluka, environmental requirements, waste management plan, water management system criteria, water quality data, transport licensing and security procedures, rehabilitation plus specialist studies into ore characteristics, noise issues and haulage risk assessment. Copyright (1996) Energy Resources of Australia Limited

The safety of Ontario's nuclear power reactors. A scientific and technical review. Vol. 2: Appendices

International Nuclear Information System (INIS)

Hare, F.K.

1988-01-01

These appendices contain seven detailed elaborations of matters covered more superficially in the Technical Report. They have been written by well-known authorities, or by the professional staff of the Review. They are essential supplements to the condensed material of the Technical Report. Several of the appendices contain detailed recommendations. Some of these have been incorporated into the Review's overall conclusions and recommendations. Others stand alone, as the opinions of the appendices' authors. I am in broad agreement with most of them, but have preferred to leave them within the authors' material. I hope that they will be given detailed study by appropriate bodies, especially Ontario Hydro and the Atomic Energy Control Board

Immunohistochemistry - Microarray Analysis of Patients with Peritoneal Metastases of Appendiceal or Colorectal Origin

Directory of Open Access Journals (Sweden)

Danielle E Green

2015-01-01

Full Text Available BackgroundThe value of immunohistochemistry (IHC-microarray analysis of pathological specimens in the management of patients is controversial although preliminary data suggests potential benefit. We describe the characteristics of patients undergoing a commercially available IHC-microarray method in patients with peritoneal metastases (PM and the feasibility of this technique in this population.MethodsWe retrospectively analyzed consecutive patients with pathologically confirmed PM from appendiceal or colorectal primary who underwent Caris Molecular IntelligenceTM testing. IHC, microarray, FISH and mutational analysis were included and stratified by PCI score, histology and treatment characteristics. Statistical analysis was performed using non-parametric tests.ResultsOur study included 5 patients with appendiceal and 11 with colorectal PM. The median age of patients was 51 (IQR 39-65 years, with 11(68% female. The median PCI score of the patients was 17(IQR 10-25. Hyperthermic intra-peritoneal chemoperfusion (HIPEC was performed in 4 (80% patients with appendiceal primary tumors and 4 (36% with colorectal primary. KRAS mutations were encountered in 40% of appendiceal vs. 30% colorectal tumors, while BRAF mutations were seen in 40% of colorectal PM and none of the patients with appendiceal PM (p=0.06. IHC biomarker expression was not significantly different between the two primaries. Sufficient tumor for microarray analysis was found in 44% (n=7 patients, which was not associated with previous use of chemotherapy (p>0.20 for 5-FU/LV, Irinotecan and Oxaliplatin.ConclusionsIn a small sample of patients with peritoneal metastases, the feasibility and results of IHC-microarray staining based on a commercially available test is reported. The apparent high incidence of the BRAF mutation in patients with PM may potentially offer opportunities for novel therapeutics and suggest that IHC-microarray is a method that can be used in this population.

Role of grounded ship 'MV River Princess' in triggering erosion: A case study from Candolim Sinquerim Coast, Goa.

Digital Repository Service at National Institute of Oceanography (India)

ManiMurali, R.; Babu, M.T.; Sudhesh, K.; Mascarenhas, A.; Vethamony, P.

are conducive for sand bar formation on the lee side. The intensity of winds and higher significant wave height (Hs) during SW monsoon further deteriorates the shore front which has already become fragile due to severe erosion along beach front...

Evaluation, engineering and development of advanced cyclone processes. Final separating media evaluation and test report (FSMER). Appendices

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-05-01

This report consists of appendices pertaining to the separating media evaluation (calcium nitrate solution) and testing for an advanced cyclone process. Appendices include: materials safety data, aqueous medium regeneration, pH control strategy, and other notes and data.

Managing dental erosion.

Science.gov (United States)

Curtis, Donald A; Jayanetti, Jay; Chu, Raymond; Staninec, Michal

2012-01-01

The clinical signs of dental erosion are initially subtle, yet often progress because the patient remains asymptomatic, unaware and uninformed. Erosion typically works synergistically with abrasion and attrition to cause loss of tooth structure, making diagnosis and management complex. The purpose of this article is to outline clinical examples of patients with dental erosion that highlight the strategy of early identification, patient education and conservative restorative management. Dental erosion is defined as the pathologic chronic loss of dental hard tissues as a result of the chemical influence of exogenous or endogenous acids without bacterial involvement. Like caries or periodontal disease, erosion has a multifactorial etiology and requires a thorough history and examination for diagnosis. It also requires patient understanding and compliance for improved outcomes. Erosion can affect the loss of tooth structure in isolation of other cofactors, but most often works in synergy with abrasion and attrition in the loss of tooth structure (Table 1). Although erosion is thought to be an underlying etiology of dentin sensitivity, erosion and loss of tooth structure often occurs with few symptoms. The purpose of this article is threefold: first, to outline existing barriers that may limit early management of dental erosion. Second, to review the clinical assessment required to establish a diagnosis of erosion. And third, to outline clinical examples that review options to restore lost tooth structure. The authors have included illustrations they hope will be used to improve patient understanding and motivation in the early management of dental erosion.

Appendices for: Improper Signaling in Two-Path Relay Channels

KAUST Repository

Gaafar, Mohamed

2016-12-01

This document contains the appendices for the work in “Improper Signaling in Two-Path Relay Channels,” which is submitted to 2017 IEEE International Conference on Communications (ICC) Workshop on Full-Duplex Communications for Future Wireless Networks, Paris, France.

Appendices for: Improper Signaling in Two-Path Relay Channels

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Schaefer, Rafael F.; Alouini, Mohamed-Slim

2016-01-01

This document contains the appendices for the work in “Improper Signaling in Two-Path Relay Channels,” which is submitted to 2017 IEEE International Conference on Communications (ICC) Workshop on Full-Duplex Communications for Future Wireless Networks, Paris, France.

Low-Grade Appendiceal Mucinous Neoplasm Involving the Endometrium and Presenting with Mucinous Vaginal Discharge

OpenAIRE

Vavinskaya, Vera; Baumgartner, Joel M.; Ko, Albert; Saenz, Cheryl C.; Valasek, Mark A.

2016-01-01

Primary appendiceal mucinous lesions are uncommon and represent a spectrum from nonneoplastic mucous retention cysts to invasive adenocarcinoma. Low-grade appendiceal mucinous neoplasms (LAMNs) represent an intermediate category on this spectrum and can be classified according to whether or not they are confined to the appendix. Although LAMNs are frequently confined to the appendix, they can also spread to the peritoneum and clinically progress as pseudomyxoma peritonei (i.e., mucinous ascit...

Wind turbine environmental assessment -- Vol 1: Screening document

International Nuclear Information System (INIS)

2000-04-01

The environmental effects of the proposed construction and operation of up to three wind turbines on the Toronto waterfront are evaluated in accordance with the requirements of the Canadian Environmental Assessment Act (CEAA) and Regulations. The nine sections of the report provide background on the environmental assessment and the wind turbine project; provide justification for the project and describes alternative sites and wind turbine technologies; outlines the scope of the project; sketches the biophysical and socio-economic environment; presents an evaluation of the environmental impacts and proposed mitigating measures; describes the public consultation program that was carried out; summarizes the comments received from interested parties; presents the conclusion of the environmental impact assessment; and responds to the public comments received on the draft screening document. Most of the concerns raised involved avoidance reactions by birds, disruption or fragmentation of wildlife, the potential for high kill rate of small nocturnal migrants and young birds, and the effect of noise on breeding birds. The overall recommendation of the consultants is that the project is not likely to cause significant adverse environmental effects and its construction and operations should be authorized. 115 refs., 8 tabs., 2 figs. (14 appendices are in volume 2)

Nutrient losses by wind and water, measurements and modelling

NARCIS (Netherlands)

Visser, S.M.; Stroosnijder, L.; Chardon, W.J.

2005-01-01

In the Sahelian zone of West-Africa, erosion by both wind and water causes a serious decline in fertility of the already low fertile soils. Despite the fact that the flow of nutrients has been intensively investigated by the use of nutrient balances, little attention has been paid to the

Measurement and data analysis methods for field-scale wind erosion studies and model validation

NARCIS (Netherlands)

Zobeck, T.M.; Sterk, G.; Funk, R.F.; Rajot, J.L.; Stout, J.E.; Scott Van Pelt, R.

2003-01-01

Accurate and reliable methods of measuring windblown sediment are needed to confirm, validate, and improve erosion models, assess the intensity of aeolian processes and related damage, determine the source of pollutants, and for other applications. This paper outlines important principles to

Comparison of erosion and erosion control works in Macedonia, Serbia and Bulgaria

Directory of Open Access Journals (Sweden)

Ivan Blinkov

2013-12-01

Natural conditions in the Balkan countries contribute to the appearance of various erosion forms and the intensity of the erosion processes. Over the history of these countries, people who settled this region used the available natural resources to fill their needs (tree cutting, incorrect plugging, overgrazing, which contributed to soil erosion. Organized erosion control works in the Balkans started in the beginning of the 20th century (1905 in Bulgaria. The highest intensity of erosion control works were carried out during the period 1945 – 1990. Various erosion control works were launched. Bulgaria had a large anti-erosion afforestation, almost 1 million ha. Bulgaria's ecological river restoration approach has been in use for almost 50 years. Serbia contributed significant erosion and torrent control works on hilly agricultural areas. Specific screen barrages and afforestation on extremely dry areas are characteristic in Macedonia. A common characteristic for all countries is a high decrease in erosion control works in the last 20 years.

Erosion-corrosion

International Nuclear Information System (INIS)

Aghili, B.

1999-05-01

A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment

Economic optimization of offshore wind farms

International Nuclear Information System (INIS)

Pauling, T.

1996-09-01

The study on the title subject continues the development of a cost model for offshore wind farms started at the Institute for Wind Energy (IW) in 1995, and applies it on different kinds of cost analyses. The model will be considered within the European research project 'Structural and Economic Optimization of Bottom-Mounted Offshore Wind Energy Converters' (Opti-OWECS, JOR3-CT95-0087) co-ordinated by the IW, where also the cost analyses and optimization will be extended. The conclusions of the investigations have already been presented at the European Union Wind Energy Conference '96 at Goeteborg, Sweden. In Chapter 1, a short overview of former offshore studies and projects is given, especially those dealing with cost analysis. Typical cost breakdowns of offshore and onshore wind farms are compared. Chapter 2 contains a brief description of the cost model in its present state. The recent improvements and extensions are documented in Chapter 3, and a validation by means of a recalculation of two former offshore studies is carried out in Chapter 4. In Chapter 5, four different offshore sites are compared with respect to the same farm size and an optimized farm design: Jade in the German part of the North Sea near Wilhelmshafen; Swansea Bay in the Bristol Channel at the British Atlantic Coast; Rostock at the German Baltic Coast, and IJmuiden in the Dutch part of the North Sea. In Chapter 6, a sensitivity study is carried out for a variety of site, design and economical parameters. The results of this project are summarized in Chapter 7, and an outlook is given in Chapter 8. The appendix contains among others a description of the SCOptiM2 code, where the model is implemented, as well as data obtained from the parameter studies and design optimizations. 30 figs., 8 tabs., 6 appendices, 40 refs

Coupled Wave Energy and Erosion Dynamics along a Salt Marsh Boundary, Hog Island Bay, Virginia, USA

Directory of Open Access Journals (Sweden)

Anthony M. Priestas

2015-09-01

Full Text Available The relationship between lateral erosion of salt marshes and wind waves is studied in Hog Island Bay, Virginia USA, with high-resolution field measurements and aerial photographs. Marsh retreat is compared to wave climate calculated in the bay using the spectral wave-model Simulating Waves Nearshore (SWAN. We confirm the existence of a linear relationship between long-term salt marsh erosion and wave energy, and show that wave power can serve as a good proxy for average salt-marsh erosion rates. At each site, erosion rates are consistent across several temporal scales, ranging from months to decades, and are strongly related to wave power. On the contrary, erosion rates vary in space and weakly depend on the spatial distribution of wave energy. We ascribe this variability to spatial variations in geotechnical, biological, and morphological marsh attributes. Our detailed field measurements indicate that at a small spatial scale (tens of meters, a positive feedback between salt marsh geometry and wave action causes erosion rates to increase with boundary sinuosity. However, at the scale of the entire marsh boundary (hundreds of meters, this relationship is reversed: those sites that are more rapidly eroding have a marsh boundary which is significantly smoother than the marsh boundary of sheltered and slowly eroding marshes.

The Monsoon Erosion Pump and the Indian Monsoon since Eocene

Science.gov (United States)

Giosan, L.

2017-12-01

Lack of consensus on the Neogene establishment and evolution of the Indian Monsoon is remarkable after half a century of research. Conflicting interpretations point toward the possibility of periodic decoupling between monsoon winds and monsoon precipitation. Here I introduce the concept of a monsoon erosion pump based on terrestrial and oceanic records reconstructed from recent NGHP and IODP drilling and spanning the last 34 million years in the Bay of Bengal, Arabian and Andaman Seas. From millennial to orbital to tectonic timescales, these records suggest that vegetation land cover interacts and modulates the regime of erosion and weathering under perennial but variable monsoonal rain conditions. Under this new proposed paradigm the Indian monsoon exhibits two distinct flavours during the Neogene that can be largely explained by its heartbeat, or astronomical forcing, mediated by the global glacial state and interacting with the paleogeography of South Asia.

Temporal and spatial variation of maximum wind speed days during the past 20 years in major cities of Xinjiang

Science.gov (United States)

Baidourela, Aliya; Jing, Zhen; Zhayimu, Kahaer; Abulaiti, Adili; Ubuli, Hakezi

2018-04-01

Wind erosion and sandstorms occur in the neighborhood of exposed dust sources. Wind erosion and desertification increase the frequency of dust storms, deteriorate air quality, and damage the ecological environment and agricultural production. The Xinjiang region has a relatively fragile ecological environment. Therefore, the study of the characteristics of maximum wind speed and wind direction in this region is of great significance to disaster prevention and mitigation, the management of activated dunes, and the sustainable development of the region. Based on the latest data of 71 sites in Xinjiang, this study explores the temporal evolution and spatial distribution of maximum wind speed in Xinjiang from 1993 to 2013, and highlights the distribution of annual and monthly maximum wind speed and the characteristics of wind direction in Xinjiang. Between 1993 and 2013, Ulugchat County exhibited the highest number of days with the maximum wind speed (> 17 m/s), while Wutian exhibited the lowest number. In Xinjiang, 1999 showed the highest number of maximum wind speed days (257 days), while 2013 showed the lowest number (69 days). Spring and summer wind speeds were greater than those in autumn and winter. There were obvious differences in the direction of maximum wind speed in major cities and counties of Xinjiang. East of the Tianshan Mountains, maximum wind speeds are mainly directed southeast and northeast. North and south of the Tianshan Mountains, they are mainly directed northwest and northeast, while west of the Tianshan Mountains, they are mainly directed southeast and northwest.

Subseabed disposal program annual report, January-December 1979. Volume II. Appendices (principal investigator progress reports). Part 1 of 2

International Nuclear Information System (INIS)

Talbert, D.M.

1981-04-01

Volume II of the sixth annual report describing the progress and evaluating the status of the Subseabed Disposal Program contains the appendices referred to in Volume I, Summary and Status. Because of the length of Volume II, it has been split into two parts for publication purposes. Part 1 contains Appendices A-O; Part 2 contains Appendices P-FF. Separate abstracts have been prepared of each Appendix for inclusion in the Energy Data Base

Subseabed disposal program annual report, January-December 1979. Volume II. Appendices (principal investigator progress reports). Part 2 of 2

International Nuclear Information System (INIS)

Talbert, D.M.

1981-04-01

Volume II of the sixth annual report describing the progress and evaluating the status of the Subseabed Disposal Program contains the appendices referred to in Volume II, Summary and Status. Because of the length of Volume II, it has been split into two parts for publication purposes. Part 1 contains Appendices A-O; Part 2 contains Appendices P-FF. Separate abstracts have been prepared for each appendix for inclusion in the Energy Data Base

Appendiceal diverticulum associated with chronic appendicitis

OpenAIRE

Zubieta-O’Farrill, Gregorio; Guerra-Mora, José Raúl; Gudiño-Chávez, Andrés; Gonzalez-Alvarado, Carlos; Cornejo-López, Gilberto Bernabe; Villanueva-Sáenz, Eduardo

2014-01-01

INTRODUCTION: Appendiceal diverticulosis is a rare entity, with a global incidence between 0.004% and 2.1% of all appendectomies. It has been related with an elevated risk of perforation in comparison to acute appendicitis, as well as an increased risk for synchronic appendicular cancer in 48% of the cases, and colonic cancer in 43%. The incidence of chronic appendicitis has been reported in 1.5% of all appendicitis cases. PRESENTATION OF CASE: We present a 73-year-old female, with no rele...

Wind Vision. A New Era for Wind Power in the United States (Executive Summary, Full Report, and Appendices); U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

Energy Technology Data Exchange (ETDEWEB)

None, None

2015-03-02

The Wind Vision analysis demonstrates the economic value that wind power can bring to the nation, a value exceeding the costs of deployment. Wind’s environmental benefits can address key societal challenges such as climate change, air quality and public health, and water scarcity. Wind deployment can provide U.S. jobs, U.S. manufacturing, and lease and tax revenues in local communities to strengthen and support a transition of the nation’s electricity sector towards a low-carbon U.S. economy. The path needed to achieve 10% wind by 2020, 20% by 2030, and 35% by 2050 requires new tools, priorities, and emphases beyond those forged by the wind industry in growing to 4.5% of current U.S. electricity demand. Consideration of new strategies and updated priorities as identified in the Wind Vision could provide substantial positive outcomes for future generations.

Funding California Schools: The Revenue Limit System. Technical Appendices

Science.gov (United States)

Weston, Margaret

2010-01-01

This document presents the technical appendices accompanying the report, "Funding California Schools: The Revenue Limit System." Included are: (1) Revenue Limit Calculation and Decomposition; (2) Data and Methods; and (3) Base Funding Alternative Simulation Results. (Contains 5 tables and 26 footnotes.) [For the main report,…

Differential erosion and the formation of layered yardangs in the Loulan region (Lop Nur), eastern Tarim Basin

Science.gov (United States)

Lin, Yongchong; Xu, Lishuai; Mu, Guijin

2018-02-01

Yardangs are a type of wind-sculpted landform which generally form in hyper-arid regions. Several factors affect the development of yardangs, and the relative importance of these factors likely varies with differences in regional environmental factors. In the Loulan region of Lop Nur, wind dynamics are the principal factor affecting the development of yardangs. However, layered yardangs, which have undergone a unique form of differential erosion, are common in the region. These erosional landforms differ from typical yardangs which are eroded solely by abrasion and deflation. We conducted field and laboratory investigations of layered yardangs to determine their origin. The results indicate that there are two types of strata comprising the yardangs: uncompacted sand-silt layers, with a lower carbonate content; and compacted clay-silt layers, with a higher carbonate content. Both types of strata are horizontal and occur in alternating layers. This type of structure enables the wind to more easily erode the less resistant sand-silt layers at different heights, leaving the more resistant compacted clay-silt layers relatively intact. Eventually the undercut remnant clay-silt layers collapse once the weight of the suspended strata exceeds their elastic resistance (more than 90% of the fallen blocks have length/thickness ratios between 1.2 and 2.5). Therefore, in addition to wind dynamics, the lithology and structure of the strata are important factors affecting the development of the layered yardangs. This type of differential erosion accelerates the development of the yardangs in the Loulan region.

Intra-appendiceal air at CT: Is it a seful or a onfusing sign for the diagnosis of acute appendicitis?

International Nuclear Information System (INIS)

Hong, Hye Suk; Cho, Hyun Suk; Woo, Ji Young; Lee, Yul; Yang, Ik; Hwang, Ji Young; Kim, Han Myun; Kim, Jeong Won

2016-01-01

To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis. We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis. Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p < 0.001). The amount of appendiceal air was significantly lesser in patients having appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p < 0.05). Areas under the ROC curves were not significantly different between strategies 1 and 2 in reader 1 (0.971 vs. 0.985, respectively; p = 0.056), but showed a small difference in reader 2 (0.969 vs. 0.986, respectively; p = 0.042). Although significant differences were seen in the prevalence, amount, and appearance of intra-appendiceal air between patients with and without appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis

Intra-appendiceal air at CT: Is it a seful or a onfusing sign for the diagnosis of acute appendicitis?

Energy Technology Data Exchange (ETDEWEB)

Hong, Hye Suk; Cho, Hyun Suk; Woo, Ji Young; Lee, Yul; Yang, Ik; Hwang, Ji Young; Kim, Han Myun; Kim, Jeong Won [Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of)

2016-02-15

To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis. We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis. Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p < 0.001). The amount of appendiceal air was significantly lesser in patients having appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p < 0.05). Areas under the ROC curves were not significantly different between strategies 1 and 2 in reader 1 (0.971 vs. 0.985, respectively; p = 0.056), but showed a small difference in reader 2 (0.969 vs. 0.986, respectively; p = 0.042). Although significant differences were seen in the prevalence, amount, and appearance of intra-appendiceal air between patients with and without appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis.

Monitoring Soil Erosion of a Burn Site in the Central Basin and Range Ecoregion: Final Report on Measurements at the Gleason Fire Site, Nevada

Energy Technology Data Exchange (ETDEWEB)

Miller, Julianne [DRI; Etyemezian, Vicken [DRI; Shillito, Rose [DRI; Cablk, Mary [DRI; Fenstermaker, Lynn [DRI; Shafer, David [DOE Legacy Management

2013-10-01

The increase in wildfires in arid and semi-arid parts of Nevada and elsewhere in the southwestern United States has implications for post-closure management and long-term stewardship for Soil Corrective Action Units (CAUs) on the Nevada National Security Site (NNSS) for which the Nevada Field Office of the United States Department of Energy, National Nuclear Security Administration has responsibility. For many CAUs and Corrective Action Sites, where closure-in-place alternatives are now being implemented or considered, there is a chance that these sites could burn over at some time while they still pose a risk to the environment or human health, given the long half lives of some of the radionuclide contaminants. This study was initiated to examine the effects and duration of wildfire on wind and water erodibility on sites analogous to those that exist on the NNSS. The data analyzed herein were gathered at the prescribed Gleason Fire site near Ely, Nevada, a site comparable to the northern portion of the NNSS. Quantification of wind erosion was conducted with a Portable In-Situ Wind ERosion Lab (PI-SWERL) on unburned soils, and on interspace and plant understory soils within the burned area. The PI-SWERL was used to estimate emissions of suspendible particles (particulate matter with aerodynamic diameters less than or equal to 10 micrometers) at different wind speeds. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Based on nearly three years of data, the Gleason Fire site does not appear to have returned to pre burn wind erosion levels. Chemical composition data of suspendible particles are variable and show a trend toward pre-burn levels, but provide little insight into how the composition has been changing over time since the fire. Soil, runoff, and sediment data were collected from the Gleason Fire site to monitor the water erosion potential over the nearly three-year period. Soil

Modeling erosion of unsaturated compacted bentonite by groundwater flow; pinhole erosion test case

International Nuclear Information System (INIS)

Laurila, T.; Sane, P.; Olin, M.; Koskinen, K.

2012-01-01

Document available in extended abstract form only. Erosion of compacted clay material by water flow is a critical factor affecting the performance of radioactive waste confinement. Our emphasis in this work is the buffer of KBS-3V concept, proposed to be compacted MX-80 bentonite. Unsaturated erosion occurs during the saturation phase of the EBS, and the main quantity of interest is the total buffer mass carried away by a groundwater flow that induces erosion by forming piping channels near the buffer/rock interface. The purpose of this work is to provide modeling tools to support erosion experiments. Role of modeling is first to interpret experimental observations in terms of processes, and to estimate robustness of experimental results. Secondly, we seek to scale up results from the laboratory scale, particularly to time scales longer than those experimentally accessible. We have performed modeling and data analysis pertaining to tests of unsaturated clay erosion. Pinhole experiments were used to study this erosion case. The main differences to well-understood pinhole erosion tests are that the material is strongly swelling and that the water flow is not determined by the pressure head but by the total flux. Groundwater flow in the buffer is determined by the flux because pressure losses occur overwhelmingly in the surrounding rock, not in the piping channel. We formulate a simple model that links an effective solid diffusivity -based swelling model to erosion by flow on the solid/liquid interface. The swelling model is similar in concept to that developed at KTH, but simpler. Erosion in the model is caused by laminar flow in the pinhole, and happens in a narrow region at the solid/liquid interface where velocity and solid volume fraction overlap. The erosion model can be mapped to erosion by wall shear, and can thus be considered as extension of that classic erosion model. The main quantity defining the behavior of clay erosion in the model is the ratio of

Investigation of the interactions between wind turbines and radio systems aimed at establishing co-siting guidelines. Phase 1: Introduction and modelling of wind turbine scatter, appendices E, F and G

International Nuclear Information System (INIS)

Dabis, H.S.; Chignell, R.J.

1997-01-01

The potential for wind turbines to interfere with radio systems can be a source of conflict between radio operators and the wind energy community. In this report, the problem of accurately predicting the effects of wind turbines on radio systems with the aim of establishing guidelines for their installation is investigated. Initially models for the scatter mechanisms that occur at the wind turbine are developed. These models predict the wind turbine radar cross section and the modulation effects due to the rotation of the blades. Initial validation of these models is established by comparing the predicted results with a set of measurements obtained from experiments performed on a 20:1 scale model wind turbine. It is shown that generally these results agree well. These results are then used in the guideline formulation to compute, for specific radio systems, regions where wind turbines cannot be installed. Examples using realistic parameters for various radio systems are presented. Further validation of the derived models is required. (author)

Rainfall Erosivity in Europe

DEFF Research Database (Denmark)

Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale

2015-01-01

Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the Rfactor in the USLE model and its revised version, RUSLE. At national...... and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based...

CFD evaluation of erosion rate around a bridge near a sand dune

Science.gov (United States)

He, Wei; Huang, Ning; Dun, Hongchao; Wang, Wenbo

2017-04-01

This study performs a series of simulations through solving the Navier-Stokes equations and the RNG k-ε turbulence model to investigate the wind erosion rates around a bridge in a desert area with sand dunes. The digital elevation model of sand dunes and the bridge model are obtained respectively from hypsographic map and construction drawings. Through combining them into the CFD software of Fluent the simulation zone was formed. The data of wind speed obtained from field observation is fitted into a logarithm format, which was imported into Fluent model as a inlet wind speed condition. Then, the effect of Dun-Go railway on wind-blown sand movement of the neighbouring environment is simulated. The results exhibit that affected by both the sand dune and bridge, the flow field is in a complex condition. It is also shown that the bridge in upstream of the sand dune will not increase the sand transport rate intensively, but change both wind velocity gradient and turbulence kinetic energy over surface of sand dune. On the other hand, when the bridge is built downstream the sand dune, simulation results show that sand deposition rate would be decreased in reference region downstream the pier.

Estimating surface soil erosion losses and mapping erosion risk for Yusufeli micro-catchment (Artvin

Directory of Open Access Journals (Sweden)

Mustafa Tüfekçioğlu

2016-10-01

Full Text Available Sheet erosion, one of the most important types of water erosion, takes place on the top soil as tiny soil layer movement that affects lake and stream ecosystem. This type of erosion is very important because the productive soil layer on the top soil can be lost in a very short period of time. The goal of this study was to quantify the amount of surface (sheet and rill soil erosion, and to identify areas under high erosion risk within the study area at Yusufeli province in Artvin by using RUSLE erosion methodology. As a result of the study it was found that the average annual potential soil loss by surface erosion was 3.6 ton ha-1yr-1. Additionally, the maps produced and conclusions reached by the study revealed that the areas of high erosion risk were identified spatially and measures to control erosion on some of these high risk areas can be possible with appropriate erosion control techniques.

EOLICARE project: airborne wind turbine; Projet EOLICARE: eolienne aeroportee

Energy Technology Data Exchange (ETDEWEB)

Benhaiem, Pierre

2010-09-15

1 -- Introduction : a) General context b) Actual schematics of wind energy c)Towards a method for converting upper-level winds energy d) Planned airborne operating systems using kites. 2 - Study of the method called OrthoKiteBunch (OKB) :a) Technical aspects and comments of schematics in appendix b) Advantages and estimated costs) 3 - System implementation of OKB in the energy mix, study of synergies and possible complementarities :a) OKB installations-thermal plant b) Nuclear installation-OKB. 4 - Conclusion. References. Schematics. Appendices. Illustrations. [French] 1 -- Introduction : a) Contexte general b) Schemas actuels de l'energie eolienne c)Vers une methode de conversion de l'energie des vents de haute altitude d) Systemes d'exploitation aeroportes envisages mettant en oeuvre des cerfs-volants. 2 - Etude de la methode dite OrthoKiteBunch (OKB) :a) Aspects techniques et commentaires des schemas en annexe b) Avantages et couts estimes) 3 - Implantation du systeme OKB au sein du bouquet energetique,etude des synergies et complementarites possibles :a) Installations OKB-centrale thermique b) Installations nucleaire-OKB. 4 - Conclusion.References.Schemas annexes.Illustrations.

The comparison of various approach to evaluation erosion risks and design control erosion measures

Science.gov (United States)

Kapicka, Jiri

2015-04-01

In the present is in the Czech Republic one methodology how to compute and compare erosion risks. This methodology contain also method to design erosion control measures. The base of this methodology is Universal Soil Loss Equation (USLE) and their result long-term average annual rate of erosion (G). This methodology is used for landscape planners. Data and statistics from database of erosion events in the Czech Republic shows that many troubles and damages are from local episodes of erosion events. An extent of these events and theirs impact are conditional to local precipitation events, current plant phase and soil conditions. These erosion events can do troubles and damages on agriculture land, municipally property and hydro components and even in a location is from point of view long-term average annual rate of erosion in good conditions. Other way how to compute and compare erosion risks is episodes approach. In this paper is presented the compare of various approach to compute erosion risks. The comparison was computed to locality from database of erosion events on agricultural land in the Czech Republic where have been records two erosion events. The study area is a simple agriculture land without any barriers that can have high influence to water flow and soil sediment transport. The computation of erosion risks (for all methodology) was based on laboratory analysis of soil samples which was sampled on study area. Results of the methodology USLE, MUSLE and results from mathematical model Erosion 3D have been compared. Variances of the results in space distribution of the places with highest soil erosion where compared and discussed. Other part presents variances of design control erosion measures where their design was done on based different methodology. The results shows variance of computed erosion risks which was done by different methodology. These variances can start discussion about different approach how compute and evaluate erosion risks in areas

Intra-Appendiceal Air at CT: Is It a Useful or a Confusing Sign for the Diagnosis of Acute Appendicitis?

Science.gov (United States)

Cho, Hyun Suk; Woo, Ji Young; Lee, Yul; Yang, Ik; Hwang, Ji-Young; Kim, Han Myun; Kim, Jeong Won

2016-01-01

Objective To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis. Materials and Methods We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis. Results Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis. PMID:26798214

The possible hindrance of a 10 MW wind farm along the Noordermeerdijk in the Noordoostpolder, Netherlands, for birds

International Nuclear Information System (INIS)

Van den Bergh, L.M.J.; Spaans, A.L.

1993-01-01

The title farm comprises 14 two-bladed 750 kW wind turbines. Hindrance of wind turbines are collisions with the wind turbines and in the wake behind the blades and loss or disintegration of the natural habitat because of the presence of the wind turbines (aspect of disturbance). The title study is focused on counting the number of collision bird victims per year, and analyzing the disturbance effects on hibernating and foraging birds. It appeared that almost 150 to more than 1500 birds will collide with one of the 16 wind turbines. A few hundred tufted ducks, some tens of pochard and some tens of wild ducks per kilometer of the array will leave their natural habitat. Based on the results it is concluded that the site south of the kilometre marker 7.0 is preferred to the site directly south of kilometre marker 5.0. It is also concluded that the above-mentioned array is preferred to a wind turbine array of 16 wind turbines of 500 kW each. The results of the investigation on that array are published in a separate report for which a separate abstract has been prepared. 2 figs., 6 tabs., 2 appendices, 34 refs

Benefit-Cost Analysis of Integrated Paratransit Systems : Volume 6. Technical Appendices.

Science.gov (United States)

1979-09-01

This last volume, includes five technical appendices which document the methodologies used in the benefit-cost analysis. They are the following: Scenario analysis methodology; Impact estimation; Example of impact estimation; Sensitivity analysis; Agg...

Durability of Compressed Earth Bricks: Assessing Erosion Resistance Using the Modified Spray Testing

Directory of Open Access Journals (Sweden)

Malarvizhi Baskaran

2010-11-01

Full Text Available The discussion in this paper is part of research directed at establishing optimal stabilization strategy for compressed bricks. The deployment context for the use of the compressed bricks was Dar es Salaam (Tanzania where manually fabricated bricks are increasingly being used in low cost housing units. This discussion specifically focuses on strategies that can be used to counter deterioration due to wind-driven rain erosion. The impact of using cement, lime, fiber and a commercial stabilizing fluid was assessed. Factory-produced bricks were used for benchmarking. The durability of the bricks was assessed using the “modified” Bulletin 5 Spray Test. The different brick specimens were sprayed with water at 2.07 MPa and 4.14 MPa over one-hour time period while measuring the depth of erosion every 15 minutes. Factory-produced bricks hardly eroded at both 2.07 MPa and 4.14 MPa pressure levels. The maximum depth of erosion for Soil-Cement bricks ranged from a maximum of 0.5 mm at 2.07 MPa water pressure to 0.8 mm at 4.14 MPa. The maximum and minimum depths of erosion for Soil-Cement-Lime bricks were 25mm and 17 mm respectively. The inclusion of natural fiber in the bricks resulted in a sharp increase of the erosion depth to a maximum of 40 mm at 2.07 MPa and 55 mm at 4.14 Mpa. As the use of natural fibers and lime enhances some physio-mechanical properties, further research is necessary to determine ways of achieving this goal while maintaining acceptable levels of erosion resistance.

A tale of two appendices – an unexpected finding | Heetun | South ...

African Journals Online (AJOL)

Abstract. Anomalies of the appendix are uncommon and are usually discovered incidentally during surgery for appendicitis. We present a rare case of appendiceal duplication, which can have serious consequences if overlooked during an operation.

Focus on Mentee-Mentor Relationships: The 10th Grade Implementation of iMentor's College Ready Program. Technical Appendices

Science.gov (United States)

Merrill, Lisa; Kang, David; Siman, Nina; Soltani, Jasmine

2016-01-01

This document presents the technical appendices that accompany the full report entitled:"Focus on Mentee-Mentor Relationships: The 10th Grade Implementation of iMentor's College Ready Program." The appendices include: (1) Mentor Survey Construct Items; (2) Qualative Data Collection and Analysis Methods; and (3) Methods for Estimating the…

Predicting of soil erosion with regarding to rainfall erosivity and soil erodibility

Science.gov (United States)

Suif, Zuliziana; Razak, Mohd Amirun Anis Ab; Ahmad, Nordila

2018-02-01

The soil along the hill and slope are wearing away due to erosion and it can take place due to occurrence of weak and heavy rainfall. The aim of this study is to predict the soil erosion degree in Universiti Pertahanan Nasional Malaysia (UPNM) area focused on two major factor which is soil erodibility and rainfall erosivity. Soil erodibility is the possibilities of soil to detach and carried away during rainfall and runoff. The "ROM" scale was used in this study to determine the degree of soil erodibility, namely low, moderate, high, and very high. As for rainfall erosivity, the erosive power caused by rainfall that cause soil loss. A daily rainfall data collected from January to April was analyzed by using ROSE index classification to identify the potential risk of soil erosion. The result shows that the soil erodibilty are moderate at MTD`s hill, high at behind of block Lestari and Landslide MTD hill, and critical at behind the mess cadet. While, the highest rainfall erosivity was recorded in March and April. Overall, this study would benefit the organization greatly in saving cost in landslide protection as relevant authorities can take early measures repairing the most affected area of soil erosion.

Study of the French wind sector: assessment, prospective, and strategy. Final report + Synthesis

International Nuclear Information System (INIS)

Bellini, Robert; Berrou, Yolene; Blot, Jean-Francois; Bodiguel, Aude; Callonnec, Gael; Cals, Guilain; Eyang Mbeng, Rudy; Fiol, Jack; Galiano, Mila; Gerard, Rolland; Gerson, Raphael; Guenard, Vincent; Guillot, Frederic; Guyet, Samy; Khebchache, Bouzid; Marchal, David; Parrouffe, Jean-Michel; Puygrenier, Samuel; Roger, Christophe; Furois, Timothee; Lejzerzon, Victoire; Mouhamad, Sakina; Orta, Louis; Glita, Marc; Meteyer, Herve; Plante, Ludovic; Duclos, Paul; Lettry, Marion; Mathieu, Mathilde; Langlois, Pierre-Albert; Lioret, Sonia; Monnier, Matthieu; Robin-Chevallier, Lucas; Bourdier, Pierre; Duffes, Thomas; Nocodie, Serge; Neveux, Guillaume; Paulou, Julien; Vermeulen, Valentin; Hajjar, Ali; Bouchet, Alexandre; Clicquot De Mentque, Juliette; Jan, Etienne; Pinel, Julie; Haeusler, Laurence; Moro-Goubely, Anne-Gaelle; Berthoin, Guillaume

2017-09-01

This huge document comprises several reports, and first proposes an executive summary which gives a synthetic overview of the present status of wind energy in France and abroad, of an assessment of 15 years of a policy of support to wind energy, of perspectives of development on the medium term, of economic spin-off on the long term, and of the ADEME's role in a national strategy for wind energy. These issues are then addressed in a more detailed way with notably a presentation of complete wind energy costs in France, a synthesis of an international benchmark, a detailed analysis of the support policy (in terms of efficiency, usefulness, costs-benefits), a characterisation of market evolutions, a discussion of constraint evolutions and of development strategies. A synthetic version of this report is then provided. More detailed reports are proposed on the various issues: first, analysis of the chain value, status of the sector in France and international benchmark; secondly, an assessment of the support policy through an assessment, a prospective and strategy, and then a detailed discussion of macro-economic spin-off and of jobs in the sector on the long term in association with wind energy development. A third part proposes a presentation of ADEME's strategy and action plan in favour of wind energy. Finally, a set of appendices contains presentations of survey questionnaires and of survey result processing, presentations of results regarding actors and countries, and presentation of modelling methodologies

Mesh erosion after abdominal sacrocolpopexy.

Science.gov (United States)

Kohli, N; Walsh, P M; Roat, T W; Karram, M M

1998-12-01

To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management.

Business plan: Supplemental draft environmental impact statement. Volume 2. Appendices

International Nuclear Information System (INIS)

1995-02-01

This document contains the appendices for the Bonneville Power Administration (BPA) Business Plan: Supplemental Draft Environmental Impact Statement. Included are: BPA products and services; Rate design; Methodology and assumptions for numerical analysis; Retail utility operations; Comments and responses to the draft business plan EIS

The environmental energy sector programme. Poland: Appendices to feasibility study

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-07-01

The appendices contain Energy Law, Act of 10 April 1997 and also more specific details from the feasibility study for the procurement of a financial solution to the modernisation of the combined heat and power plant in the city of Zielona Gora, Poland. (EHS)

Business Plan : Supplemental Draft Environmental Impact Statement, Volume 2, Appendices.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1995-02-01

This document contains the appendices for the Bonneville Power Administration (BPA) Business Plan: Supplemental Draft Environmental Impact Statement. Included are: BPA products and services; Rate design; Methodology and assumptions for numerical analysis; Retail utility operations; Comments and responses to the draft business plan EIS.

Susceptibility of bovine dental enamel with initial erosion lesion to new erosive challenges.

Science.gov (United States)

Oliveira, Gabriela Cristina de; Tereza, Guida Paola Genovez; Boteon, Ana Paula; Ferrairo, Brunna Mota; Gonçalves, Priscilla Santana Pinto; Silva, Thiago Cruvinel da; Honório, Heitor Marques; Rios, Daniela

2017-01-01

This in vitro study evaluated the impact of initial erosion on the susceptibility of enamel to further erosive challenge. Thirty bovine enamel blocks were selected by surface hardness and randomized into two groups (n = 15): GC- group composed by enamel blocks without erosion lesion and GT- group composed by enamel blocks with initial erosion lesion. The baseline profile of each block was determined using the profilometer. The initial erosion was produced by immersing the blocks into HCl 0.01 M, pH 2.3 for 30 seconds, under stirring. The erosive cycling consisted of blocks immersion in hydrochloric acid (0.01 M, pH 2.3) for 2 minutes, followed by immersion in artificial saliva for 120 minutes. This procedure was repeated 4 times a day for 5 days, and the blocks were kept in artificial saliva overnight. After erosive cycling, final profile measurement was performed. Profilometry measured the enamel loss by the superposition of initial and final profiles. Data were analyzed by t-test (perosion on bovine dental enamel does not enhance its susceptibility to new erosive challenges.

Oxygen isotopic ratios of quartz from wind-erosive soils of southwestern United States in relation to aerosol dust

Energy Technology Data Exchange (ETDEWEB)

Sridhar, K.; Jackson, M.L.; Clayton, R.N.; Gillette, D.A.; Hawley, J.W.

1978-01-01

The oxygen isotopic ratios (expressed as parts per thousand relative to mean ocean water, SMOW, delta/sup 18/O) of the quartz from 13 soils undergoing much wind erosion during the study period of 1972-1975 in four southwestern states and from comparison areas were determined. The delta/sup 18/O for quartz from eight Texas (TX) and Arizona (AZ) soils range from 13.0 to 15.9 /sup 0///sub 00/. The quartz of the sands and silts coarser than 20 ..mu..m from three of the soils had delta/sup 18/O values ranging from 13.1 to 15.1 /sup 0///sub 00/, characteristic of an ultimate igneous-metamorphic origin. The delta/sup 18/O values increase greatly with decreasing particle size of quartz from three soils ranging from loamy fine sand to loam to clay in texture. The delta/sup 18/O of the 1-10 ..mu..m quartz fraction (aerosol size) ranged from 19.2 to 20.2 /sup 0///sub 00/ (19.55 +- 0.28 /sup 0///sub 00/; +- sigma) for the thirteen soils most affected by dust storms. The oxygen isotopic ratios of 1-10 ..mu..m quartz from three Hawaiian soils and two sediments from Lake Waiau occurring at 3,970 m altitude on the Mauna Kea summit on the Island of Hawaii give a delta/sup 18/O mean of 18.3 +- 0.2 /sup 0///sub 00/.

A linear relationship between wave power and erosion determines salt-marsh resilience to violent storms and hurricanes

Science.gov (United States)

Leonardi, Nicoletta; Ganju, Neil K.; Fagherazzi, Sergio

2016-01-01

Salt marsh losses have been documented worldwide because of land use change, wave erosion, and sea-level rise. It is still unclear how resistant salt marshes are to extreme storms and whether they can survive multiple events without collapsing. Based on a large dataset of salt marsh lateral erosion rates collected around the world, here, we determine the general response of salt marsh boundaries to wave action under normal and extreme weather conditions. As wave energy increases, salt marsh response to wind waves remains linear, and there is not a critical threshold in wave energy above which salt marsh erosion drastically accelerates. We apply our general formulation for salt marsh erosion to historical wave climates at eight salt marsh locations affected by hurricanes in the United States. Based on the analysis of two decades of data, we find that violent storms and hurricanes contribute less than 1% to long-term salt marsh erosion rates. In contrast, moderate storms with a return period of 2.5 mo are those causing the most salt marsh deterioration. Therefore, salt marshes seem more susceptible to variations in mean wave energy rather than changes in the extremes. The intrinsic resistance of salt marshes to violent storms and their predictable erosion rates during moderate events should be taken into account by coastal managers in restoration projects and risk management plans.

A linear relationship between wave power and erosion determines salt-marsh resilience to violent storms and hurricanes.

Science.gov (United States)

Leonardi, Nicoletta; Ganju, Neil K; Fagherazzi, Sergio

2016-01-05

Salt marsh losses have been documented worldwide because of land use change, wave erosion, and sea-level rise. It is still unclear how resistant salt marshes are to extreme storms and whether they can survive multiple events without collapsing. Based on a large dataset of salt marsh lateral erosion rates collected around the world, here, we determine the general response of salt marsh boundaries to wave action under normal and extreme weather conditions. As wave energy increases, salt marsh response to wind waves remains linear, and there is not a critical threshold in wave energy above which salt marsh erosion drastically accelerates. We apply our general formulation for salt marsh erosion to historical wave climates at eight salt marsh locations affected by hurricanes in the United States. Based on the analysis of two decades of data, we find that violent storms and hurricanes contribute less than 1% to long-term salt marsh erosion rates. In contrast, moderate storms with a return period of 2.5 mo are those causing the most salt marsh deterioration. Therefore, salt marshes seem more susceptible to variations in mean wave energy rather than changes in the extremes. The intrinsic resistance of salt marshes to violent storms and their predictable erosion rates during moderate events should be taken into account by coastal managers in restoration projects and risk management plans.

Susceptibility of bovine dental enamel with initial erosion lesion to new erosive challenges.

Directory of Open Access Journals (Sweden)

Gabriela Cristina de Oliveira

Full Text Available This in vitro study evaluated the impact of initial erosion on the susceptibility of enamel to further erosive challenge. Thirty bovine enamel blocks were selected by surface hardness and randomized into two groups (n = 15: GC- group composed by enamel blocks without erosion lesion and GT- group composed by enamel blocks with initial erosion lesion. The baseline profile of each block was determined using the profilometer. The initial erosion was produced by immersing the blocks into HCl 0.01 M, pH 2.3 for 30 seconds, under stirring. The erosive cycling consisted of blocks immersion in hydrochloric acid (0.01 M, pH 2.3 for 2 minutes, followed by immersion in artificial saliva for 120 minutes. This procedure was repeated 4 times a day for 5 days, and the blocks were kept in artificial saliva overnight. After erosive cycling, final profile measurement was performed. Profilometry measured the enamel loss by the superposition of initial and final profiles. Data were analyzed by t-test (p<0.05. The result showed no statistically significant difference between groups (GS = 14.60±2.86 and GE = .14.69±2.21 μm. The presence of initial erosion on bovine dental enamel does not enhance its susceptibility to new erosive challenges.

Erosion problems in Alexandroupolis coastline, North-Eastern Greece

Science.gov (United States)

Xeidakis, G. S.; Delimani, P.; Skias, S.

2007-12-01

This paper deals with the coastal erosion processes and the related problems around the city of Alexandroupolis, NE Aegean Sea, N. Greece. The area is very fast developing, as the city is an important port and a summer resort center in SE Balkans, and will become soon a transportation and energy center, as well. The coastline under study exhibits an east west orientation and has a length of more than 50 km. The spatial distribution and the characteristics of the changes in the shoreline were studied by comparing old and new air photographs and topographic maps, as well as through repeated series of field observations and local measurements regarding the erosion process. From these studies it was concluded that the greater stretch of the western part of the coast, under consideration, is of moderate to high relief, with a considerable participation of coastal cliffs. It consists of conglomerates of varying granulometry and consistency and is under moderate to severe erosion process. The erosion phenomena in the western part of the coast may be attributed, primarily, to strong S, SW winds, blowing in the area and to trapping of sediments by Alexandroupolis’ port breakwaters; the port stops or/and diverts the sediments to the open sea; and to the east to west longshore sea current, prevailing in the area. The eastern stretch of the coast is a plain area, formed by sandy silty sediments; being a part of the river Evros’ Delta, it is under deposition and accretes seawards. The majority of the coasts under consideration are classified as coasts of high wave energy potential. Hard structures, as shore protection measures, have been constructed in some places, but they were proved, in rather short time-period, ineffective and suffered extensive failures. Thus, it is argued that for a long-term cost-effective tackling of the various erosion problems on any stretch, priority must be given to soft engineering measures; although, certain hard measures, carefully selected

Fuel Rod Consolidation Project: Phase 2, Final report: Volume 2, Appendices

International Nuclear Information System (INIS)

1987-01-01

This document, Volume 2, provides the appendices to Volume 1 of the Fuel Rod Consolidation Project. It provides information on the following: References; Trade-off Studies; Instrument List; RAM Data; Fabrication Specifications; Software Specifications; and Design Requirements

Component Fragility Research Program: Phase 1, Demonstration tests: Volume 2, Appendices

International Nuclear Information System (INIS)

Holman, G.S.; Chou, C.K.; Shipway, G.D.; Glozman, V.

1987-08-01

Appendices are presented which contain information concerning: details of controller and relay installation; resonance search transmissibility plots; time-history data from runs 17, 31, 46, and 56; and response spectra from runs 17, 31, 46, and 56

Large scale solar district heating. Evaluation, modelling and designing - Appendices

Energy Technology Data Exchange (ETDEWEB)

Heller, A.

2000-07-01

The appendices present the following: A) Cad-drawing of the Marstal CSHP design. B) Key values - large-scale solar heating in Denmark. C) Monitoring - a system description. D) WMO-classification of pyranometers (solarimeters). E) The computer simulation model in TRNSYS. F) Selected papers from the author. (EHS)

Assessment of accident risks in the CRBRP. Volume 2. Appendices

Energy Technology Data Exchange (ETDEWEB)

None

1977-03-01

Appendices to Volume I include core-related accident-sequence definition, CRBRP risk-assessment sequence-probability determinations, failure-probability data, accident scenario evaluation, radioactive material release analysis, ex-core accident analysis, safety philosophy and design features, calculation of reactor accident consequences, sensitivity study, and risk from fires.

Theoretical studies of fusion physics. Volume II. Appendices. Final report

International Nuclear Information System (INIS)

1983-01-01

The following appendices are given: (1) absorption of waves near the cyclotron frequency by relativistic electrons in EBT, (2) power balance in a stable, adiabatic hot electron annulus, (3) whistler instability in a relativistic electron annulus, and (4) adiabatic limit on electron temperature in the EBT annulus

Wind reduction patterns around isolated biomass for wind erosion control in a desertified area of Central Sudan

NARCIS (Netherlands)

Nasr Al-amin, N.K.; Stigter, C.J.; El-Tayeb Mohammed, A.

2010-01-01

The aim of this study was to assess the effectiveness of sparse vegetation, feature common in arid zone, to reduce wind force (velocity) and hence protect the surface and regions downwind from drifting sand and their consequences. Respectively 4 (with heights h of 4, 3.2, 2 and 1.66 m), 2 (with h of

Protection from erosion following wildfire

Science.gov (United States)

Peter R. Robichaud; William J. Elliot

2006-01-01

Erosion in the first year after a wildfire can be up to three orders of magnitude greater than the erosion from undisturbed forests. To mitigate potential postfire erosion, various erosion control treatments are applied on highly erodible areas with downstream resources in need of protection. Because postfire erosion rates generally decline by an order of magnitude for...

Performance of Generating Plant: Managing the Changes. Part 3: Renewable energy plant: reports on wind, photovoltaics and biomas energies

Energy Technology Data Exchange (ETDEWEB)

Manoha, Bruno; Cohen, Martin [Electricite de France (France)

2008-05-15

The WEC Committee on the Performance of Generating Plant (PGP) has been collecting and analysing power plant performance statistics worldwide for more than 30 years and has produced regular reports, which include examples of advanced techniques and methods for improving power plant performance through benchmarking. A series of reports from the various working groups was issued in 2008. This reference presents the results of Working Group 3 (WG3). WG3 will promote the introduction of performance indicators for renewable energy generating plant (wind, geothermal, solar and biomass) developed by the Committee. It will also assess selected transitional technology issues and environmental factors related to non-conventional technologies. The WG3 report includes sections on Wind Energy Today, Photovoltaics Energy Today, Biomass Electricity Today and appendices.

N+3 Aircraft Concept Designs and Trade Studies. Volume 2; Appendices-Design Methodologies for Aerodynamics, Structures, Weight, and Thermodynamic Cycles

Science.gov (United States)

Greitzer, E. M.; Bonnefoy, P. A.; delaRosaBlanco, E.; Dorbian, C. S.; Drela, M.; Hall, D. K.; Hansman, R. J.; Hileman, J. I.; Liebeck, R. H.; Lovegren, J.;

Soil erosion in Iran: Issues and solutions

Science.gov (United States)

Hamidreza Sadeghi, Seyed; Cerdà, Artemi

2015-04-01

Journal of Geosciences, 7(5), 1941-1950. Khaledi Darvishan, A., Sadeghi, S. H., Homaee, M., Arabkhedri, M. 2013. Measuring sheet erosion using synthetic color-contrast aggregates. Hydrological Processes. Mahmoodabadi, M. Cerdà, A. 2013. WEPP calibration for improved predictions on interril erosion in semi-arid to arid enviorments. Geoderma, 204-205,75-83. http://dx.doi.org/10.1016/j.geoderma.2013.04.013, Mehdizade, B., Asadi, H., Shabanpour, M., Ghadiri, H. 2013. Impact of erosion and tillage on the productivity and quality of selected semiarid soils of Iran. International Agrophysics, 27(3), 291-297. Moghadam, B. K., Jabarifar, M., Bagheri, M., Shahbazi, E. 2015. Effects of land use change on soil splash erosion in the semi-arid region of Iran. Geoderma, 241, 210-220. Nosrati, K., Ahmadi, F. 2013. Monitoring of soil organic carbon and nitrogen stocks in different land use under surface water erosion in a semi-arid drainage basin of Iran. Journal of Applied Sciences and Environmental Management, 17(2), 225-230. Nourzadeh, M., Bahrami, H. A., Goossens, D., Fryrear, D. W. 2013. Determining soil erosion and threshold friction velocity at different soil moisture conditions using a portable wind tunnel. Zeitschrift für Geomorphologie, 57(1), 97-109. Sadeghi, S. H. R., Seghaleh, M. B., Rangavar, A. S. 2013. Plot sizes dependency of runoff and sediment yield estimates from a small watershed. Catena, 102, 55-61. Sadeghi, S. H. R., Seghaleh, M. B., Rangavar, A. S. 2013. Plot sizes dependency of runoff and sediment yield estimates from a small watershed. Catena, 102, 55-61. Sadeghi, S. H., Najafi, S., Riyahi Bakhtiari, A., Abdi, P. 2014. Ascribing soil erosion types for sediment yield using composite fingerprinting technique. Hydrological Sciences Journal, 59(9), 1753-1762. Taghizadeh-Mehrjardi, R., Minasny, B., Sarmadian, F., Malone, B. P. 2014. Digital mapping of soil salinity in Ardakan region, central Iran. Geoderma, 213, 15-28.

Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

Science.gov (United States)

Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

2013-11-01

This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil.

Shipping container response to severe highway and railway accident conditions: Appendices

International Nuclear Information System (INIS)

Fischer, L.E.; Chou, C.K.; Gerhard, M.A.; Kimura, C.Y.; Martin, R.W.; Mensing, R.W.; Mount, M.E.; Witte, M.C.

1987-02-01

Volume 2 contains the following appendices: Severe accident data; truck accident data; railroad accident data; highway survey data and bridge column properties; structural analysis; thermal analysis; probability estimation techniques; and benchmarking for computer codes used in impact analysis. (LN)

Friction, wear, and erosion atlas

CERN Document Server

Budinski, Kenneth G

2013-01-01

"Fundamental aspects of concepts are explained clearly and simply…[and] are supported by illustrations and images of worn surfaces. In addition the book contains a number of appendices, which provide useful engineering information related to tribology."-Raymond G. Bayer, Tribology Consultant, USA

Mapping erosion from space

NARCIS (Netherlands)

Vrieling, A.

2007-01-01

Soil erosion by water is the most important land degradation problem worldwide. Spatial information on erosion is required for defining effective soil and water conservation strategies. Satellite remote sensing can provide relevant input to regional erosion assessment. This thesis comprises a review

The possible hindrance of a 8 MW wind farm along the Zuidermeerdijk in the Noordoostpolder, Netherlands, for birds. De mogelijke hinder van een 8 MW windpark langs de Zuidermeerdijk (NOP) voor vogels

Energy Technology Data Exchange (ETDEWEB)

Van den Bergh, L M.J.; Spaans, A L

1993-01-01

The title farm comprises 16 three-bladed 500 kW wind turbines. Hindrance of wind turbines are collisions with the wind turbines and in the wake behind the blades and loss or disintegration of the natural habitat because of the presence of the wind turbines (aspect of disturbance). The title study is focused on counting the number of collision bird victims per year, and analyzing the disturbance effects on hibernating and foraging birds. It appeared that almost 150 to more than 1500 birds will collide with one of the 16 wind turbines. A few hundred tufted ducks, some tens of pochard and some tens of wild ducks per kilometre of the wind farm will leave their natural habitat. Based on the results it is concluded that the dike area between kilometre marker 32.5 and kilometre marker 35.5 is the most suitable area for a wind turbine array along the Zuidermeerdijk in between Schokkerhaven and Ketelbrug, both Netherlands. 3 figs., 5 tabs., 2 appendices, 33 refs.

[Expression of receptors of estrogens and androgens in the testicular appendices].

Science.gov (United States)

Paredes Esteban, R M; Luque Barona, R J; Velasco Sánchez, B; Rodríguez Vargas, J; Lorite, A; García Ruiz, M

2008-07-01

The appendices or hidátides of the testicle are structures that are considered an embryonic rest. In testicular hidátide estrogen receivers have been demonstrated but in the epididimys the results vary. Has been theorized that the elevation of the estrogen levels in the puberty can produce an inflammation and torsion of hidátide, nevertheless, in the epididimys in which the estrogen expression is not clear (and also they are twisted) the theory is put in doubt. This controversy takes us to the accomplishment of this work. A prospective study is made in 20 testicular appendices, of which 7 from the epididimys are extirpated of patients to whom an escrotal exploration is made in the development of surgery of processes of the inguino-escrotal channel (hidroceles, hernias). Optical microscopy and inmunohistoquímical study are analyzed by means of using prediluted monoclonales antibodies, for receivers of estrogens, androgens and proliferative index. The results were proceed and analyzed by means of SPSS statistical program. All hidátides, testicular and from the epididimarys expressed receivers for estrogens without significant difference among them, not existing differences as far as the location of receiving sayings within the three compartments of hidátide. The number of estrogen receivers was in relation to the age of the patient. Only hidátides from the epididimys fundamentally expressed receivers of located androgens and at level of ductus. We have not found significant relation between the proliferative index and the expression of estrogen receivers. The proliferative index was more elevated at level of ductus. 1) As much the testicular appendices as those from the epididimays expressed receivers of estrogens at level of the three compartments. It makes think about a same embryonic origin, although only the epididimal ones expressed androgen receivers. 2) the observation of estrogen receivers in both types of hidátides, as well as the relation of the

Erosive gastritis

International Nuclear Information System (INIS)

Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

1982-01-01

Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported. (orig.)

Erosive gastritis

Energy Technology Data Exchange (ETDEWEB)

Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

1982-08-01

Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported.

Assessing storm erosion hazards

NARCIS (Netherlands)

Ranasinghe, Ranasinghe W M R J B; Callaghan, D.; Ciavola, Paolo; Coco, Giovanni

2017-01-01

The storm erosion hazard on coasts is usually expressed as an erosion volume and/or associated episodic coastline retreat. The accurate assessment of present-day and future storm erosion volumes is a key task for coastal zone managers, planners and engineers. There are four main approaches that can

Measurement of erosion: Is it possible?

NARCIS (Netherlands)

Stroosnijder, L.

2005-01-01

Reasons for erosion measurements are: (1) to determine the environmental impact of erosion and conservation practices, (2) scientific erosion research; (3) development and evaluation of erosion control technology; (4) development of erosion prediction technology and (5) allocation of conservation

Mapping Soil Erosion Factors and Potential Erosion Risk for the National Park "Central Balkan"

Science.gov (United States)

Ilieva, Diliana; Malinov, Ilia

2014-05-01

Soil erosion is widely recognised environmental problem. The report aims at presenting the main results from assessment and mapping of the factors of sheet water erosion and the potential erosion risk on the territory of National Park "Central Balkan". For this purpose, the Universal Soil Loss Equation (USLE) was used for predicting soil loss from erosion. The influence of topography (LS-factor) and soil erodibility (K-factor) was assessed using small-scale topographic and soil maps. Rainfall erosivity (R-factor) was calculated from data of rainfalls with amounts exceeding 9.5 mm from 14 hydro-meteorological stations. The values of the erosion factors (R, K and LS) were presented for the areas of forest, sub-alpine and alpine zones. Using the methods of GIS, maps were plotted presenting the area distribution among the classes of the soil erosion factors and the potential risk in the respective zones. The results can be used for making accurate decisions for soil conservation and sustainable land management in the park.

Initial Northwest Power Act Power Sales Contracts : Final Environmental Impact Statement. Volume 2, Appendices A--L.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1992-01-01

This report consists of appendices A-L of the final environmental impact statement for the Bonneville Power Administration. The appendices provide information on the following: Ninth circuit Court opinion in Forelaws on Board v. Johnson; guide to Northwest Power act contracts; guide to hydro operations; glossary; affected environment supporting documentation; environmental impacts of generic resource types; information on models used; technical information on analysis; public involvement activities; bibliography; Pacific Northwest Electric Power Planning and Conservation Act; and biological assessment. (CBS)

The influence of rill density on soil erosion against USLE-soil erosion methode

OpenAIRE

Rizalihadi, A.M.; Faimah, B.E.; Nazia, C.L.

2013-01-01

Land and water is one of the major natural resource which has an important role for human life. Exploitation of land in catchment areas that not correspond to its carrying capacity will cause damage. One of the effect is increassing the soil erosion. Continuous erosion will also lead to increased sediment transport in rivers that disrupt the ship navigation on estuary due sediment accumulation. At present, soil erosion is estimated using USLE method, which is only limited to the erosion in th...

Hybrid Composite Material and Solid Particle Erosion Studies

Science.gov (United States)

Chellaganesh, D.; Khan, M. Adam; Ashif, A. Mohamed; Ragul Selvan, T.; Nachiappan, S.; Winowlin Jappes, J. T.

2018-04-01

Composite is one of the predominant material for most challenging engineering components. Most of the components are in the place of automobile structure, aircraft structures, and wind turbine blade and so on. At the same all the components are indulged to mechanical loading. Recent research on composite material are machinability, wear, tear and corrosion studies. One of the major issue on recent research was solid particle air jet erosion. In this paper hybrid composite material with and without filler. The fibre are in the combination of hemp – kevlar (60:40 wt.%) as reinforcement using epoxy as a matrix. The natural material palm and coconut shell are used as filler materials in the form of crushed powder. The process parameter involved are air jet velocity, volume of erodent and angle of impingement. Experiment performed are in eight different combinations followed from 2k (k = 3) factorial design. From the investigation surface morphology was studied using electron microscope. Mass change with respect to time are used to calculate wear rate and the influence of the process parameters. While solid particle erosion the hard particle impregnates in soft matrix material. Influence of filler material has reduced the wear and compared to plain natural composite material.

NEW CLASSIFICATION AND DIAGNOSIS OF APPENDICEAL CARCINOID TUMORS

Directory of Open Access Journals (Sweden)

Vuka Katić

2012-03-01

Full Text Available Carcinoid tumours are rare lesions that belong to the APUDoma category having the capacity of Amine Precursor Uptake and Decarboxylase. Gastrointestinal system comprises 90% of all carcinoids in the body and they are the most common type of primary malignant lesions of the appendix. New WHO classification of gastrointestinal carcinoids, diagnostic dilemmas of some carcinoid variants and, sometimes unpredictable prognosis are the reasons for the following study: clinical, macro- and microscopical as well as cytochemical and immunocytochemical examination of the vermiform appendix carcinoids, surgically removed from 16 patients. The appendectomy was induced by acute appendicitis or tumorous mass, without carcinoid syndrome. After two-day fixation in 10% formaldehyde, routinelly processed and embedded in paraffin, laboratory sections were stained with H&E, Fontana-Masson’s, Grimelius’, FIF and ABPAS methods. ABC method has been used for immunohistochemical examination. The antibodies for Chromogranin A, NSE, Synaptophysin, Cytokeratin 7, S-100 protein, Ki67 and CEA (primary antibodies and ABC (secondary antibody (Dako Kopenhagen were tested. The patients had no carcinoid syndrome. The most frequent was classic appendiceal carcinoid, well differentiated - NETG1 (8 cases, without metastases; goblet cell carcinoids were rare (3 cases, one case with liver metastases. The second case of goblet cell carcinoid was associated with cystadenoma papillare mucinosum, complicated by pseudomixoma peritonei and the third case was limited only to appendiceal wall. The patient with liver metastases died five months after appendectomy. The patient with goblet cell carcinoid associated with papillary mucinous cystadenoma and complicated by pseudomixoma peritonei had re-operation with both partial cecal and right ovarial resection, associated with washing the peritoneal cavity. The patient was feeling well during six years from the second operation. Based on our

Impact of erosion and accretion on the distribution of enterococci in beach sands.

Science.gov (United States)

Gast, Rebecca J; Gorrell, Levi; Raubenheimer, Britt; Elgar, Steve

2011-09-15

Bacterial pathogens in coastal sediments may pose a health risk to users of beaches. Although recent work shows that beach sands harbor both indicator bacteria and potential pathogens, it is not known how deep within beach sands the organisms may persist nor if they may be exposed during natural physical processes. In this study, sand cores of approximately 1 m depth were collected at three sites across the beach face in Kitty Hawk, North Carolina before, during and after large waves from an offshore hurricane. The presence of DNA from the fecal indicator bacterium Enterococci was detected in subsamples at different depths within the cores by PCR amplification. Erosion and accretion of beach sand at the three sites also was determined for each sampling day. The results indicate that ocean beach sands with persisting enterococci signals could be exposed and redistributed when wind, waves, and currents cause beach erosion or accretion.

Saliva and dental erosion.

Science.gov (United States)

Buzalaf, Marília Afonso Rabelo; Hannas, Angélicas Reis; Kato, Melissa Thiemi

2012-01-01

Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. This review discusses the role of salivary factors on the development of dental erosion. A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

Saliva and dental erosion

Directory of Open Access Journals (Sweden)

Marília Afonso Rabelo Buzalaf

2012-10-01

Full Text Available Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. Objective: This review discusses the role of salivary factors on the development of dental erosion. Material and Methods: A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Results: Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Conclusions: Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices

International Nuclear Information System (INIS)

1977-09-01

Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant

Auto consolidated cohesive sediments erosion; Erosion des sediments cohesifs en autoconsolidation

Energy Technology Data Exchange (ETDEWEB)

Ternat, F

2007-02-15

Pollutants and suspended matters of a river can accumulate into the sedimentary column. Once deposited, they are submitted to self-weight consolidation processes, ageing and burying, leading to an increase of their erosion resistance. Pollutant fluxes can be related to sedimentary fluxes, determined by threshold laws. In this work, an erosion threshold model is suggested by introducing a cohesion force into the usual force balance. A model of cohesion is developed on the basis of interactions between argillaceous cohesive particles (clays), particularly the Van der Waals force, whose parameterization is ensured by means of granulometry and porosity. Artificial erosion experiments were performed in a recirculating erosion flume with natural cored sediments where critical shear stress measurements were performed. Other analyses provided granulometry and porosity. The results obtained constitute a good database for the literature. The model is then applied to the experimental conditions and gives good agreement with measurements. An example of the accounting for self-weight consolidation processes is finally suggested, before finishing on a Mohr like diagram dedicated to soft cohesive sediment erosion. (author)

Transmission System Vegetation Management Program. Draft Environmental Impact Statement - Appendices

International Nuclear Information System (INIS)

1999-01-01

The appendices covered in this Draft Environmental Impact Statement are: Appendix A--Public involvement; Appendix B--Biological weed control agents; Appendix C--BPA herbicide licensing plan; Appendix D--Sample educational information; Appendix E--Clearance criteria; Appendix F--USFS mitigation measures and background; Appendix G--BLM mitigation measures and background and Appendix H--Pesticide fact sheets

Laboratory simulation of erosion by space plasma

International Nuclear Information System (INIS)

Kristoferson, L.; Fredga, K.

1976-04-01

A laboratory experiment has been made where a plasma stream collides with targets made of different materials of cosmic interest. The experiment can be viewed as a process simulation of the solar wind particle interaction with solid surfaces in space, e.g. cometary dust. Special interest is given to sputtering of OH and Na. It is shown that the erosion of solid particles in interplanetary space at large heliocentric distances is most likely dominated by sputtering and by sublimation near the sun. The heliocentric distance of the limit between the two regions is determined mainly by the material properties of the eroded surface, e.g. heat of sublimation and sputtering yield, a typical distance being 0,5 a.u. It is concluded that the observations of Na in comets at large solar distances, in some cases also near the sun, is most likely to be explained by solar wind sputtering. OH emission in space could be of importance also from 'dry', water-free, matter by means of molecule sputtering. The observed OH production rates in comets are however too large to be explained in this way and are certainly the results of sublimation and dissociation of H 2 O from an icy nucleus. (Auth.)

Rainfall erosivity in Europe.

Science.gov (United States)

Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale; Meusburger, Katrin; Klik, Andreas; Rousseva, Svetla; Tadić, Melita Perčec; Michaelides, Silas; Hrabalíková, Michaela; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Beguería, Santiago; Alewell, Christine

2015-04-01

Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the R-factor in the USLE model and its revised version, RUSLE. At national and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based on the best available datasets. Data have been collected from 1541 precipitation stations in all European Union (EU) Member States and Switzerland, with temporal resolutions of 5 to 60 min. The R-factor values calculated from precipitation data of different temporal resolutions were normalised to R-factor values with temporal resolutions of 30 min using linear regression functions. Precipitation time series ranged from a minimum of 5 years to a maximum of 40 years. The average time series per precipitation station is around 17.1 years, the most datasets including the first decade of the 21st century. Gaussian Process Regression (GPR) has been used to interpolate the R-factor station values to a European rainfall erosivity map at 1 km resolution. The covariates used for the R-factor interpolation were climatic data (total precipitation, seasonal precipitation, precipitation of driest/wettest months, average temperature), elevation and latitude/longitude. The mean R-factor for the EU plus Switzerland is 722 MJ mm ha(-1) h(-1) yr(-1), with the highest values (>1000 MJ mm ha(-1) h(-1) yr(-1)) in the Mediterranean and alpine regions and the lowest (<500 MJ mm ha(-1) h(-1) yr(-1)) in the Nordic countries. The erosivity density (erosivity normalised to annual precipitation amounts) was also the highest in Mediterranean regions which implies high risk for erosive events and floods

Incidencia potencial de la erosión eólica sobre la degradación del suelo y la calidad del aire en distintas regiones de la Argentina Potential effects of wind erosion on soil degradation and air quality in different regions of Argentina

Directory of Open Access Journals (Sweden)

Daniel E Buschiazzo

2009-12-01

ía relativamente más a la calidad del aire que a la del suelo. La magnitud de este proceso estaría regida, principalmente, por el área disponible para la erosión. En suelos sometidos a manejos agrícolas, frecuentemente desnudos y de bajo grado de evolución como los Ustipsammentes y Haplustoles, la erosión eólica tendría efectos intermedios, afectando tanto a la calidad del suelo como a la del aire. Finalmente, en suelos relativamente más evolucionados y sometidos a manejos agrícolas como los Hapludoles, la erosión afectaría en mayor medida a la calidad del suelo, siendo la emisión de partículas finas de relativa menor importancia.Wind erosion can impact soil and air quality. The magnitude of these effects depends on the soil type and management conditions, and is associated with the transport conditions of soil particles: saltation and rolling affect soil quality to a greater extent while suspension tends to increase the emission of fine particles to the atmosphere. The objective of this research was to determine the magnitude of both type of movements in soils of Argentina, in order to predict potential effects on soil or air quality. This study was carried out in four provinces of Argentina: Chaco (CHA, San Luis (SLU, La Pampa (LPA and Río Negro (PAT. In each case, wind erosion was measured in the 1 ha-square fields by means of BSNE samplers. Results indicated that the total amount of transported material, the so-called mass flux (FM as well as the absolute amount of eroded soil (Q were higher in sites with less developed soils of SLU (Ustipsamment and LPA (Haplustoll and lower in sites with a better developed soil of CHA (Hapludoll or with less developed soil but with permanent soil cover with natural grasses of PAT (Haplargid. Saltation and rolling were the main transport forms in SLU, LPA and CHA and suspension in PAT. Though low (10%, the plant coverage existing in this last site was enough to increase the height of the wind profile and to favor the transport

Immunohistochemical Study of p53 Expression in Patients with Erosive and Non-Erosive Oral Lichen Planus

Science.gov (United States)

Shiva, Atena; Zamanian, Ali; Arab, Shahin; Boloki, Mahsa

2018-01-01

Statement of the Problem: Oral lichen planus is a common mucocutaneous lesion with a chronic inflammatory process mediated by immune factors while a few cases of the disease become malignant. Purpose: This study aimed to determine the frequency of p53 marker as a tumor suppressor in patients with erosive and non-erosive oral lichen planus (OLP) by using immunohistochemical methods. Materials and Method: This descriptive cross-sectional study investigated the p53 expression in 16 erosive OLP, 16 non-erosive OLP samples, and 8 samples of normal oral mucosa through immunohistochemistry. The percentage of stained cells in basal and suprabasal layers, and inflammatory infiltrate were graded according to the degree of staining; if 0%, 50% of the cells were stained, they were considered as (-), (+), (++), (+++) and (++++), respectively. The obtained data was statistically analyzed and compared by using Chi square and Fisher’s exact test. Results: The mean percentage of p53 positive cells in erosive OLP (34.5±14.2) was considerably higher than that in non-erosive OLP (23.8±10.4) and normal mucosa (17.5±17). There was a significant difference among the three groups of erosive, non-erosive and control in terms of staining intensity. No significant difference existed between the patients’ age and sex in the two OLP groups. Conclusion: The increased incidence of p53 from normal mucosa to erosive OLP indicated the difference between biological behavior of erosive and non-erosive OLP. It can be claimed that the erosive OLP has great premalignant potential compared with the non-erosive one.

Multiple caeco-appendiceal fistulas and diverticulosis: a newly defined congenital anomaly of the appendix-report of the first case.

Science.gov (United States)

Yucel, Ahmet Fikret; Pergel, Ahmet; Kocakusak, Ahmet; Aydin, Ibrahim; Bagci, Pelin; Sahin, Dursun Ali

2011-11-01

Congenital anomalies of the appendix are extremely rare. They are usually found incidentally during operations other than appendectomies. Congenital appendix diverticula are even less frequent. Congenital caeco-appendiceal fistulae have not been reported until today. Herein, we present real diverticula of the appendix with multiple caeco-appendiceal fistulae which, to our knowledge, is the first in the literature.

Surface erosion and sedimentation caused by ejecta from the lunar crater Tycho

Science.gov (United States)

Shkuratov, Y.; Basilevsky, A.; Kaydash, V.; Ivanov, B.; Korokhin, V.; Videen, G.

2018-02-01

We use Kaguya MI images acquired at wavelengths 415, 750, and 950 nm to map TiO2 and FeO content and the parameter of optical maturity OMAT in lunar regions Lubiniezky E and Taurus-Littrow with a spatial resolution of 20 m using the Lucey method [Lucey et al., JGR 2000, 105. 20,297]. We show that some ejecta from large craters, such as Tycho and Copernicus may cause lunar surface erosion, transportation of the eroded material and its sedimentation. The traces of the erosion resemble wind tails observed on Earth, Mars, and Venus, although the Moon has no atmosphere. The highland material of the local topographic prominences could be mobilized by Tycho's granolometrically fine ejecta and caused by its transportation along the ejecta way to adjacent mare areas and subsequent deposition. The tails of mobilized material reveal lower abundances of Ti and Fe than the surrounding mare surface. We have concluded that high-Ti streaks also seen in the Lubiniezky E site, which show unusual combinations of the TiO2 and FeO content on the correlation diagram, could be the result of erosion by Tycho's ejecta too. In these locations, Tycho's material did not form a consolidated deposit, but resulted in erosion of the mare surface material that became intermixed, consequently, diluting the ejecta. The Taurus-Littrow did provide evidence of the mechanical effect of Tycho's ejecta on the local landforms (landslide, secondary craters) and do not show the compositional signature of Tycho's ejecta probably due to intermixing with local materials and dilution.

Potential impact of wind energy development of mountain flora and fauna in Rhone-Alpes

International Nuclear Information System (INIS)

Ladet, Alain; Bauvet, Corinne

2005-03-01

After a presentation of Rhone-Alpes mountain areas (massifs, constraints related to mountain climate, vegetation levels), this report proposes an overview of elements to be taken into account for the development of wind energy. It lists the different concerned public actors, reports a bibliographical study, indicates names and locations of sensitive species (fauna and flora) and natural environments. A synthesis indicates potential impacts, and outlines the patrimonial value, and then proposes an approach for the diagnosis and for the impact study. Appendices notably contain sheets which present the different concerned vegetal or animal species, and their important characteristics in terms of habitat and life

Appendicitis complicated by appendiceal metastasis via peritoneal dissemination from lung cancer.

Science.gov (United States)

Shiota, Naoki; Furonaka, Makoto; Kikutani, Kazuya; Haji, Keiko; Fujisaki, Seiji; Nishida, Toshihiro

2016-07-01

Peritoneal disseminations from lung cancer are difficult to detect during the patient's clinical course. Therefore, complications of this condition are unclear. We report a case in which peritoneal dissemination from lung cancer complicated appendicitis. A 74-year-old man with lung cancer who was receiving maintenance therapy presented at our hospital because of abdominal pain. It was the seventh day after the 14th cycle of maintenance therapy with bevacizumab. He was diagnosed with acute appendicitis. The resected appendix showed acute appendicitis complicated by appendiceal metastasis from lung cancer. Adenocarcinoma was observed predominantly in the serous membrane from the neck to the tail of the appendix. The distribution of the adenocarcinoma was diffuse. Peritoneal dissemination was considered the route of metastasis. He was admitted to the palliative care unit 10 months after appendectomy. Appendiceal metastasis via peritoneal dissemination from lung cancer complicated appendicitis in our patient who had been receiving bevacizumab.

An Evaluation of Project Learning Tree in British Columbia. Appendices.

Science.gov (United States)

Conry, Robert F.; And Others

The volume contains seven appendices (A-G) which accompany the first volume. Appendix A provides a list of project personnel and of teachers who participated in the unit development workshop. Appendix B, composed of six sections, includes the unit lesson plans and teachers' guides used in the field study for grades 3, 5, and 7. The grade materials…

Report on corrections and future considerations for Appendices II–VIII of the International Code of Nomenclature for Algae, Fungi, and Plants

Science.gov (United States)

For the first time, the main text and Appendices II–VIII of the International Code of Nomenclature were separately published following decisions of the Melbourne Nomenclature Section, which contributed to subsequent development of an online resource capable of producing the Appendices in real time. ...

Rainfall erosivity map for Ghana

International Nuclear Information System (INIS)

Oduro Afriyie, K.

1995-10-01

Monthly rainfall data, spanning over a period of more than thirty years, were used to compute rainfall erosivity indices for various stations in Ghana, using the Fournier index, c, defined as p 2 /P, where p is the rainfall amount in the wettest month and P is the annual rainfall amount. Values of the rainfall erosivity indices ranged from 24.5 mm at Sunyani in the mid-portion of Ghana to 180.9 mm at Axim in the south western coastal portion. The indices were used to construct a rainfall erosivity map for the country. The map revealed that Ghana may be broadly divided into five major erosion risk zones. The middle sector of Ghana is generally in the low erosion risk zone; the northern sector is in the moderate to severe erosion risk zone, while the coastal sector is in the severe to extreme severe erosion risk zone. (author). 11 refs, 1 fig., 1 tab

Socioeconomic effects of the DOE Gas Centrifuge Enrichment Plant. Volume 2: appendices

International Nuclear Information System (INIS)

1979-01-01

Volume 2 contains 18 appendices: schools; fire protection; law enforcement; water and sewer systems; solid waste; health care; transportation; recreation; labor force; economic effects; finance; school finance; bibliography; contacts; project methodology; service impacts; reference tables; and response to comments

A sink for methane on Mars? The answer is blowing in the wind

NARCIS (Netherlands)

Knak Jensen, Svend J.; Skibsted, Jørgen; Jakobsen, Hans J.; ten Kate, Inge L.; Gunnlaugsson, Haraldur P.; Merrison, Jonathan P.; Finster, Kai; Bak, Ebbe; Iversen, Jens J.; Kondrup, Jens C.; Nørnberg, Per

2014-01-01

Tumbling experiments that mimic the wind erosion of quartz grains in an atmosphere of 13C-enriched methane are reported. The eroded grains are analyzed by 13C and 29Si solid-state NMR techniques after several months of tumbling. The analysis shows that methane has reacted with the eroded surface to

No-migration variance petition. Appendices C--J: Volume 5, Revision 1

Energy Technology Data Exchange (ETDEWEB)

1990-03-01

Volume V contains the appendices for: closure and post-closure plans; RCRA ground water monitoring waver; Waste Isolation Division Quality Program Manual; water quality sampling plan; WIPP Environmental Procedures Manual; sample handling and laboratory procedures; data analysis; and Annual Site Environmental Monitoring Report for the Waste Isolation Pilot Plant.

Rill erosion rates in burned forests

Science.gov (United States)

Joseph W. Wagenbrenner; Peter R. Robichaud

2011-01-01

Introduction Wildfires often produce large increases in runoff and erosion rates (e.g., Moody and Martin, 2009), and land managers need to predict the frequency and magnitude of postfire erosion to determine the needs for hazard response and possible erosion mitigation to reduce the impacts of increased erosion on public safety and valued resources. The Water Erosion...

Evaluation of the serum zinc level in erosive and non-erosive oral lichen planus.

Science.gov (United States)

Gholizadeh, N; Mehdipour, M; Najafi, Sh; Bahramian, A; Garjani, Sh; Khoeini Poorfar, H

2014-06-01

Lichen planus is a chronic inflammatory immunologic-based disease involving skin and mucosa. This disease is generally divided into two categories: erosive and non-erosive. Many etiologic factors are deliberated regarding the disease; however, the disorders of immune system and the role of cytotoxic T-lymphocytes and monocytes are more highlighted. Zinc is an imperative element for the growth of epithelium and its deficiency induces the cytotoxic activity of T-helper2 cells, which seems to be associated with lichen planus. This study was aimed to evaluate the levels of serum zinc in erosive and non-erosive oral lichen planus (OLP) and to compare it with the healthy control group to find out any feasible inference. A total of 22 patients with erosive oral lichen planus, 22 patients with non erosive OLP and 44 healthy individuals as the control group were recruited in this descriptive-comparative study. All the participants were selected from the referees to the department of oral medicine, school of dentistry, Tabriz University of Medical Sciences. Serum zinc level was examined for all the individuals with liquid-stat kit (Beckman Instruments Inc.; Carlsbad, CA). Data were analyzed by adopting the ANOVA and Tukey tests, using SPSS 16 statistical software. The mean age of patients with erosive and non-erosive LP was 41.7 and 41.3 years, respectively. The mean age of the healthy control group was 34.4 years .The mean serum zinc levels in the erosive and non erosive lichen planus groups and control groups were 8.3 (1.15), 11.15 (0.92) and 15.74 (1.75) μg/dl respectively. The difference was statistically significant (poral lichen planus. This finding may probably indicate the promising role of zinc in development of oral lichen planus.

Modeling soil erosion in a watershed

OpenAIRE

Lanuza, R.

1999-01-01

Most erosion models have been developed based on a plot scale and have limited application to a watershed due to the differences in aerial scale. In order to address this limitation, a GIS-assisted methodology for modeling soil erosion was developed using PCRaster to predict the rate of soil erosion at watershed level; identify the location of erosion prone areas; and analyze the impact of landuse changes on soil erosion. The general methodology of desktop modeling or soil erosion at watershe...

Design tradeoff studies and sensitivity analysis. Appendices B1-B4. [HYBRID

Energy Technology Data Exchange (ETDEWEB)

1979-05-25

These four appendices to the report on the Near-Term Hybrid Vehicle (NTHV) report contain information on: HYBRID computer program documentation; material substitution study for advanced hybrid vehicles; NTHV market potential; battery compartment weight distribution; and vehicle handling dynamics. (LCL)

[Acute abdomen secondary to appendiceal intussusception].

Science.gov (United States)

Betancourth-Alvarenga, J E; Vázquez-Rueda, F; Murcia-Pascual, F J; Ayala-Montoro, J

2015-01-01

Appendiceal intussusception is a rare condition that can occur at any age. Only a few cases have been reported, and most are found during surgery. The therapeutic approach is usually surgical, ranging from an appendectomy to a hemicolectomy, primarily for biopsy and to rule out possible malignancy. Three cases of children under 14 years who underwent surgery for acute abdominal pain located in the right iliac fossa are presented; one with preoperative diagnosis by ultrasound, and the other two with positive intraoperative findings of intussusception of the cecal appendix, with acute appendicitis being histologically confirmed. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

International Photovoltaic Program Plan. Volume II. Appendices

Energy Technology Data Exchange (ETDEWEB)

Costello, D.; Koontz, R.; Posner, D.; Heiferling, P.; Carpenter, P.; Forman, S.; Perelman, L.

1979-12-01

This second volume of a two-part report on the International Photovoltaic Program Plan contains appendices summarizing the results of analyses conducted in preparation of the plan. These analyses include compilations of relevant statutes and existing Federal programs; strategies designed to expand the use of photovoltaics abroad; information on the domestic photovoltaic plan and its impact on the proposed international plan; perspectives on foreign competition; industry views on the international photovoltaic market and ideas about how US government actions could affect this market; international financing issues; and information on issues affecting foreign policy and developing countries.

STUDY OF RAINFALL RATES AND EROSIVE PROCESSES AT THE URBAN AREA OF SÃO LUÍS – MA

Directory of Open Access Journals (Sweden)

Antonio José Teixeira Guerra

2005-05-01

Full Text Available The study of the rain rates is here highlighted, in order to understand the mechanisms that generate the starting point of the erosive processes. The precipitation varies spatially not only in local and regional levels, due to mechanisms that generate rains, but also in short distances, due to the control of local variations, such as winds and constructions. In this way, the precipitations should be measured in different points of the study area, depending on the interest of the study and scale of analysis.The erosive process caused by rainfall covers almost the whole terrestrial surface, especially in tropical areas where the total rainfall is higher than in other regions of the planet. Besides that, the rain only falls on specific seasons in several areas, which worsens the erosion. The process tends to accelerate as the deforestation for wood exploitation and/or agricultural production takes place, once the soils become unprotected without the vegetal cover, so that the rains affect the surface of the grounds directly (GUERRA, 1999.This work presents the results of the monitoring of erosive processes along more than three years of studies at the urban area of São Luís City, relating rainfall rates to gullies evolution, an important instrument for the control and recovery of large-scale erosive processes.

Scales and erosion

Science.gov (United States)

There is a need to develop scale explicit understanding of erosion to overcome existing conceptual and methodological flaws in our modelling methods currently applied to understand the process of erosion, transport and deposition at the catchment scale. These models need to be based on a sound under...

Coastal erosion problem, modelling and protection

Science.gov (United States)

Yılmaz, Nihal; Balas, Lale; İnan, Asu

2015-09-01

Göksu Delta, located in the south of Silifke County of Mersin on the coastal plain formed by Göksu River, is one of the Specially Protected Areas in Turkey. Along the coastal area of the Delta, coastline changes at significant rates are observed, concentrating especially at four regions; headland of İncekum, coast of Paradeniz Lagoon, river mouth of Göksu and coast of Altınkum. The coast of Paradeniz Lagoon is suffering significantly from erosion and the consequent coastal retreating problem. Therefore, the narrow barrier beach which separates Paradeniz Lagoon from the Mediterranean Sea is getting narrower, creating a risk of uniting with the sea, thus causing the disappearance of the Lagoon. The aim of this study was to understand the coastal transport processes along the coastal area of Göksu Delta to determine the coastal sediment transport rates, and accordingly, to propose solutions to prevent the loss of coastal lands in the Delta. To this end, field measurements of currents and sediment grain sizes were carried out, and wind climate, wave climate, circulation patterns and longshore sediment transport rates were numerically modeled by HYDROTAM-3D, which is a three dimensional hydrodynamic transport model. Finally, considering its special importance as an environmentally protected region, some coastal structures of gabions were proposed as solutions against the coastal erosion problems of the Delta. The effects of proposed structures on future coastline changes were also modeled, and the coastlines predicted for the year 2017 are presented and discussed in the paper.

Plants and ventifacts delineate late Holocene wind vectors in the Coachella Valley, USA

Science.gov (United States)

Griffiths, P.G.; Webb, R.H.; Fisher, M.; Muth, Allan

2009-01-01

Strong westerly winds that emanate from San Gorgonio Pass, the lowest point between Palm Springs and Los Angeles, California, dominate aeolian transport in the Coachella Valley of the western Sonoran Desert. These winds deposit sand in coppice dunes that are critical habitat for several species, including the state and federally listed threatened species Uma inornata, a lizard. Although wind directions are generally defined in this valley, the wind field has complex interactions with local topography and becomes more variable with distance from the pass. Local, dominant wind directions are preserved by growth patterns of Larrea tridentata (creosote bush), a shrub characteristic of the hot North American deserts, and ventifacts. Exceptionally long-lived, Larrea has the potential to preserve wind direction over centuries to millennia, shaped by the abrasive pruning of windward branches and the persistent training of leeward branches. Wind direction preserved in Larrea individuals and clones was mapped at 192 locations. Compared with wind data from three weather stations, Larrea vectors effectively reflect annual prevailing winds. Ventifacts measured at 24 locations record winds 10° more westerly than Larrea and appear to reflect the direction of the most erosive winds. Based on detailed mapping of local wind directions as preserved in Larrea, only the northern half of the Mission-Morongo Creek floodplain is likely to supply sand to protected U. inornata habitat in the Willow Hole ecological reserve.

Does a more sophisticated storm erosion model improve probabilistic erosion estimates?

NARCIS (Netherlands)

Ranasinghe, R.W.M.R.J.B.; Callaghan, D.; Roelvink, D.

2013-01-01

The dependency between the accuracy/uncertainty of storm erosion exceedance estimates obtained via a probabilistic model and the level of sophistication of the structural function (storm erosion model) embedded in the probabilistic model is assessed via the application of Callaghan et al.'s (2008)

INEL environmental characterization report. Volume II. Appendices A-D

International Nuclear Information System (INIS)

1984-09-01

This volume contains appendices: (1) a socioeconomic data base for southeastern Idaho; (2) an ecological characterization of the INEL; (3) site-specific climatology summary, NPR primary and alternate sites; (4) NPR site borehole completion; (5) an investigation of the principal lineament at the INEL; (6) an investigation of Clay Butte, Idaho; (7) Arco and Howe fault study; (8) seismology of the INEL; (9) geologic map of the INEL; and (1) geologic ages of the INEL

Buffer erosion in dilute groundwater

International Nuclear Information System (INIS)

Schatz, T.; Kanerva, N.; Martikainen, J.; Sane, P.; Olin, M.; Seppaelae, A.; Koskinen, K.

2013-08-01

One scenario of interest for repository safety assessment involves the loss of bentonite buffer material in contact with dilute groundwater flowing through a transmissive fracture interface. In order to examine the extrusion/erosion behavior of bentonite buffer material under such circumstances, a series of experiments were performed in a flow-through, 1 mm aperture, artificial fracture system. These experiments covered a range of solution chemistry (salt concentration and composition), material composition (sodium montmorillonite and admixtures with calcium montmorillonite), and flow velocity conditions. No erosion was observed for sodium montmorillonite against solution compositions from 0.5 g/L to 10 g/L NaCl. No erosion was observed for 50/50 calcium/sodium montmorillonite against 0.5 g/L NaCl. Erosion was observed for both sodium montmorillonite and 50/50 calcium/sodium montmorillonite against solution compositions ≤ 0.25 g/L NaCl. The calculated erosion rates for the tests with the highest levels of measured erosion, i.e., the tests run under the most dilute conditions (ionic strength (IS) < ∼1 mM), were well-correlated to flow velocity, whereas the calculated erosion rates for the tests with lower levels of measured erosion, i.e., the tests run under somewhat less dilute conditions (∼1 mM < IS < ∼4 mM), were not similarly correlated indicating that material and solution composition can significantly affect erosion rates. In every experiment, both erosive and non-erosive, emplaced buffer material extruded into the fracture and was observed to be impermeable to water flowing in the fracture effectively forming an extended diffusive barrier around the intersecting fracture/buffer interface. Additionally, a model which was developed previously to predict the rate of erosion of bentonite buffer material in low ionic strength water in rock fracture environments was applied to three different cases: sodium montmorillonite expansion in a vertical tube, a

Dynamics of soil organic carbon and microbial biomass carbon in relation to water erosion and tillage erosion.

Science.gov (United States)

Xiaojun, Nie; Jianhui, Zhang; Zhengan, Su

2013-01-01

Dynamics of soil organic carbon (SOC) are associated with soil erosion, yet there is a shortage of research concerning the relationship between soil erosion, SOC, and especially microbial biomass carbon (MBC). In this paper, we selected two typical slope landscapes including gentle and steep slopes from the Sichuan Basin, China, and used the (137)Cs technique to determine the effects of water erosion and tillage erosion on the dynamics of SOC and MBC. Soil samples for the determination of (137)Cs, SOC, MBC and soil particle-size fractions were collected on two types of contrasting hillslopes. (137)Cs data revealed that soil loss occurred at upper slope positions of the two landscapes and soil accumulation at the lower slope positions. Soil erosion rates as well as distribution patterns of the erosion is the major process of soil redistribution in the gentle slope landscape, while tillage erosion acts as the dominant process of soil redistribution in the steep slope landscape. In gentle slope landscapes, both SOC and MBC contents increased downslope and these distribution patterns were closely linked to soil redistribution rates. In steep slope landscapes, only SOC contents increased downslope, dependent on soil redistribution. It is noticeable that MBC/SOC ratios were significantly lower in gentle slope landscapes than in steep slope landscapes, implying that water erosion has a negative effect on the microbial biomass compared with tillage erosion. It is suggested that MBC dynamics are closely associated with soil redistribution by water erosion but independent of that by tillage erosion, while SOC dynamics are influenced by soil redistribution by both water erosion and tillage erosion.

1992 Columbia River Salmon Flow Measures Options Analysis/EIS : Appendices.

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described. The document concludes with an evaluation of the potential effects that could result from implementing proposed actions. The conclusions are based on evaluation of existing data, utilization of numerical models, and application of logical inference. This volume contains the appendices.

1992 Columbia River salmon flow measures Options Analysis/EIS: Appendices

International Nuclear Information System (INIS)

1992-01-01

This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described. The document concludes with an evaluation of the potential effects that could result from implementing proposed actions. The conclusions are based on evaluation of existing data, utilization of numerical models, and application of logical inference. This volume contains the appendices

Wave-current induced erosion of cohesive riverbanks in northern Manitoba, Canada

Science.gov (United States)

Kimiaghalam, N.; Clark, S.; Ahmari, H.; Hunt, J.

2015-03-01

The field of cohesive soil erosion is still not fully understood, in large part due to the many soil parameters that affect cohesive soil erodibility. This study is focused on two channels, 2-Mile and 8-Mile channels in northern Manitoba, Canada, that were built to connect Lake Winnipeg with Playgreen Lake and Playgreen Lake with Kiskikittogisu Lake, respectively. The banks of the channels consist of clay rich soils and alluvial deposits of layered clay, silts and sands. The study of erosion at the sites is further complicated because the flow-induced erosion is combined with the effects of significant wave action due to the large fetch length on the adjacent lakes, particularly Lake Winnipeg that is the seventh largest lake in North America. The study included three main components: field measurements, laboratory experiments and numerical modelling. Field measurements consisted of soil sampling from the banks and bed of the channels, current measurements and water sampling. Grab soil samples were used to measure the essential physical and electrochemical properties of the riverbanks, and standard ASTM Shelby tube samples were used to estimate the critical shear stress and erodibility of the soil samples using an erosion measurement device (EMD). Water samples were taken to estimate the sediment concentration profile and also to monitor changes in sediment concentration along the channels over time. An Acoustic Doppler Current Profiler (ADCP) was used to collect bathymetry and current data, and two water level gauges have been installed to record water levels at the entrance and outlet of the channels. The MIKE 21 NSW model was used to simulate waves using historical winds and measured bathymetry of the channels and lakes. Finally, results from the wave numerical model, laboratory tests and current measurement were used to estimate the effect of each component on erodibility of the cohesive banks.

Wave-current induced erosion of cohesive riverbanks in northern Manitoba, Canada

Directory of Open Access Journals (Sweden)

N. Kimiaghalam

2015-03-01

Full Text Available The field of cohesive soil erosion is still not fully understood, in large part due to the many soil parameters that affect cohesive soil erodibility. This study is focused on two channels, 2-Mile and 8-Mile channels in northern Manitoba, Canada, that were built to connect Lake Winnipeg with Playgreen Lake and Playgreen Lake with Kiskikittogisu Lake, respectively. The banks of the channels consist of clay rich soils and alluvial deposits of layered clay, silts and sands. The study of erosion at the sites is further complicated because the flow-induced erosion is combined with the effects of significant wave action due to the large fetch length on the adjacent lakes, particularly Lake Winnipeg that is the seventh largest lake in North America. The study included three main components: field measurements, laboratory experiments and numerical modelling. Field measurements consisted of soil sampling from the banks and bed of the channels, current measurements and water sampling. Grab soil samples were used to measure the essential physical and electrochemical properties of the riverbanks, and standard ASTM Shelby tube samples were used to estimate the critical shear stress and erodibility of the soil samples using an erosion measurement device (EMD. Water samples were taken to estimate the sediment concentration profile and also to monitor changes in sediment concentration along the channels over time. An Acoustic Doppler Current Profiler (ADCP was used to collect bathymetry and current data, and two water level gauges have been installed to record water levels at the entrance and outlet of the channels. The MIKE 21 NSW model was used to simulate waves using historical winds and measured bathymetry of the channels and lakes. Finally, results from the wave numerical model, laboratory tests and current measurement were used to estimate the effect of each component on erodibility of the cohesive banks.

The environmental impact statement for the Nevada Test Site and off-site locations in the State of Nevada. Volume 1, Appendices A-F

International Nuclear Information System (INIS)

1996-01-01

This volume contains appendices to the named document. The Appendices are entitled (A) Description of Projects and Activities, (2) Federal Register Notice, (C) Relevant Regulatory Requirements, (D) Distribution Lists, (E) Impact Assessment Methods, and (F) Project-Specific Environmental Analysis

Erhversbetinget erosion?

DEFF Research Database (Denmark)

Dige, Irene; Gjørup, Hans; Nyvad, Bente

2012-01-01

Baggrund – I forbindelse med dental erosion er en grundig udredning af patienten vigtig, således at årsagen til erosionernes opståen findes, og der kan iværksættes adækvat forebyggende indsats. En sådan udredning er ikke mindst vigtig, når arbejdsmiljøet mistænkes. Patienttilfælde – En 30-årig...... arbejdsskade, men ikke anerkendt, da erosioner ikke er optaget på Arbejdsskadestyrelsens liste over erhvervssygdomme. En systematisk registrering af lignende tilfælde kunne imidlertid på sigt ændre retspraksis for fremtidige patienter med arbejdsbetinget erosion....... patient, der arbejder som pladesmed, blev henvist til Landsdels- og Videnscenter, Århus Sygehus, med henblik på udredning af patientens kraftige slid. Patienten udviste ikke-alderssvarende tandslid af emalje og dentin svarende til erosion forårsaget af syredampe i arbejdsmiljøet, muligvis forstærket af...

Farmers' identification of erosion indicators and related erosion damage in the Central Highlands of Kenya

NARCIS (Netherlands)

Sterk, G.; Okoba, B.O.

2006-01-01

Most soil and water conservation planning approaches rely on empirical assessment methods and hardly consider farmers' knowledge of soil erosion processes. Farmers' knowledge of on-site erosion indicators could be useful in assessing the site-specific erosion risk before planning any conservation

Magnetic fields in the solar system planets, moons and solar wind interactions

CERN Document Server

Wicht, Johannes; Gilder, Stuart; Holschneider, Matthias

2018-01-01

This book addresses and reviews many of the still little understood questions related to the processes underlying planetary magnetic fields and their interaction with the solar wind. With focus on research carried out within the German Priority Program ”PlanetMag”, it also provides an overview of the most recent research in the field. Magnetic fields play an important role in making a planet habitable by protecting the environment from the solar wind. Without the geomagnetic field, for example, life on Earth as we know it would not be possible. And results from recent space missions to Mars and Venus strongly indicate that planetary magnetic fields play a vital role in preventing atmospheric erosion by the solar wind. However, very little is known about the underlying interaction between the solar wind and a planet’s magnetic field. The book takes a synergistic interdisciplinary approach that combines newly developed tools for data acquisition and analysis, computer simulations of planetary interiors an...

Spatial and temporal assessment of back-barrier erosion on Cumberland Island National Seashore, Georgia, 2011–2013

Science.gov (United States)

Calhoun, Daniel L.; Riley, Jeffrey W.

2016-07-15

Much research has been conducted to better understand erosion and accretion processes for the seaward zones of coastal barrier islands; however, at Cumberland Island National Seashore, Georgia, the greater management concern is the effect that erosion is having on the resources of the island’s western shoreline, or the back barrier. Catastrophic slumping and regular rates of erosion greater than 1 meter per year threaten important habitat, historical and pre-historical resources, and modern infrastructure on the island. Prior research has helped National Park Service (NPS) staff identify the most severe and vulnerable areas, but in order to develop effective management actions, information is needed on what forces and conditions cause erosion. To this end, the U.S. Geological Survey, in cooperation with the NPS, conducted two longitudinal surveys, one each at the beginning and end of the approximately year-long monitoring period from late 2011 to early 2013, along five selected segments of the back barrier of the Cumberland Island National Seashore. Monitoring stations were constructed at four of these locations that had previously been identified as erosional hotspots. The magnitude of erosion at each location was quantified to determine the relative influence of causative agents. Results indicate that erosion is, in general, highly variable within and among these segments of the Cumberland Island National Seashore’s back barrier. Observed erosion ranged from a maximum of 2.5 meters of bluff-line retreat to some areas that exhibited no net erosion over the 1-year study period. In terms of timing of erosion, three of the four sites were primarily affected by punctuated erosional events that were coincident with above-average high tides and elevated wind speeds. The fourth site exhibited steady, low-magnitude retreat throughout the study period. While it is difficult to precisely subscribe certain amounts of erosion to specific agents, this study provides

Primary appendiceal lymphoma presenting as suspected perforated acute appendicitis: clinical, sonography and CT findings with pathologic correlation.

Science.gov (United States)

Guo, Jingjing; Wu, Gang; Chen, Xiaojun; Li, Xiaodong

2014-01-01

The gastrointestinal tract is the most common site for extranodal involvement by non-Hodgkin's lymphoma. However, primary appendiceal lymphomas presenting as perforated acute appendicitis are very rare: they occur in only 0.015% of all gastrointestinal lymphoma cases. The management of this condition is still controversial, and a multimodality approach (e.g., surgery, radiation therapy, and chemotherapy) is the optimal treatment. In these cases, appendiceal non-Hodgkin's lymphomas typically manifest with acute symptoms in patients with no prior lymphoma history. Additionally, we treated our patient with a right hemicolectomy and postoperative multiagent chemotherapy.

Local Agenda 21 in Apeldoorn, Netherlands. Appendices

International Nuclear Information System (INIS)

Dullens, M.; Schouw, J.C.; Straatman, T.G.

1999-08-01

The (im)possibilities of concrete projects to start Local Agenda 21 activities in Apeldoorn, Netherlands, are discussed. Attention is paid to options with respect to transportation, energy conservation, water use, soil pollution, waste management, and nature. Local Agenda 21 is a program by means of which local governments can contribute to sustainable targets as formulated during the 1992 conference Agenda 21 of the United Nations (UN). The appendices contain background information (reports of meetings, elaboration of ecological subjects in relation with socio-economic subjects, and a table with all the recommendations) and are published in this report. The main report is a separate publication

Divertor erosion in DIII-D

International Nuclear Information System (INIS)

Whyte, D.G.; Bastasz, R.; Wampler, W.R.; Brooks, J.N.; West, W.P.; Wong, C.P.C.

1998-05-01

Net erosion rates of carbon target plates have been measured in situ for the DIII-D lower divertor. The principal method of obtaining this data is the DiMES sample probe. Recent experiments have focused on erosion at the outer strike-point of two divertor plasma conditions: (1) attached (Te > 40 eV) ELMing plasmas and (2) detached (Te 10 cm/year, even with incident heat flux 2 . In this case, measurements and modeling agree for both gross and net carbon erosion, showing the near-surface transport and redeposition of the carbon is well understood and that effective sputtering yields are > 10%. In ELM-free discharges, this erosion rate can account for the rate of carbon accumulation in the core plasma. Divertor plasma detachment eliminates physical sputtering, while spectroscopically measured chemical erosion yields are also found to be low (Y(C/D + ) ≤ 2.0 x 10 -3 ). This leads to suppression of net erosion at the outer strike-point, which becomes a region of net redeposition (∼ 4 cm/year). The private flux wall is measured to be a region of net redeposition with dense, high neutral pressure, attached divertor plasmas. Leading edges intercepting parallel heat flux (∼ 50 MW/m 2 ) have very high net erosion rates (∼ 10 microm/s) at the OSP of an attached plasma. Leading edge erosion, and subsequent carbon redeposition, caused by tile gaps can account for half of the deuterium codeposition in the DIII-D divertor

Molybdenum erosion measurements in Alcator C-Mod

Energy Technology Data Exchange (ETDEWEB)

Wampler, W.R. [Sandia National Labs., Albuquerque, NM (United States); LaBombard, B.; Lipshultz, B.; Pappas, D.; Pitcher, C.S. [Massachusetts Inst. of Tech., Cambridge, MA (United States); McCracken, G.M. [JET Joint Undertaking, Abingdon (United Kingdom)

1998-05-01

Erosion of molybdenum was measured on a set of 21 tiles after a run campaign of 1,090 shots in the Alcator C-Mod tokamak. The net erosion of molybdenum, was determined from changes in the depth of a thin chromium marker layer measured by Rutherford backscattering. Net Mo erosion was found to be approximately 150 nm near the outer divertor strike point, and much less everywhere else. Gross erosion rates by sputtering were estimated using ion energies and fluxes obtained from Langmuir probe measurements of edge-plasma conditions. Predicted net erosion using calculated gross erosion with prompt redeposition and measured net erosion agree within a factor of 3. Sputtering by boron and molybdenum impurities dominates erosion.

Mapping monthly rainfall erosivity in Europe.

Science.gov (United States)

Ballabio, Cristiano; Borrelli, Pasquale; Spinoni, Jonathan; Meusburger, Katrin; Michaelides, Silas; Beguería, Santiago; Klik, Andreas; Petan, Sašo; Janeček, Miloslav; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Tadić, Melita Perčec; Diodato, Nazzareno; Kostalova, Julia; Rousseva, Svetla; Banasik, Kazimierz; Alewell, Christine; Panagos, Panos

2017-02-01

Rainfall erosivity as a dynamic factor of soil loss by water erosion is modelled intra-annually for the first time at European scale. The development of Rainfall Erosivity Database at European Scale (REDES) and its 2015 update with the extension to monthly component allowed to develop monthly and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part of Britain and Ireland) in May and the highest values are registered during summer months. Starting from September, R-factor has a decreasing trend. The mean rainfall erosivity in summer is almost 4 times higher (315MJmmha -1 h -1 ) compared to winter (87MJmmha -1 h -1 ). The Cubist model has been selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency, the sum of all months has to be close to annual erosivity. The performance of the Cubist models proved to be generally high, resulting in R 2 values between 0.40 and 0.64 in cross-validation. The obtained months show an increasing trend of erosivity occurring from winter to summer starting from western to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive events. Consequently, spatio-temporal mapping of rainfall erosivity permits to identify the months and the areas with highest risk of soil loss where conservation measures should be

The Effect of Air Density on Sand Transport Structures and the Adobe Abrasion Profile: A Field Wind-Tunnel Experiment Over a Wide Range of Altitude

Science.gov (United States)

Han, Qingjie; Qu, Jianjun; Dong, Zhibao; Zu, Ruiping; Zhang, Kecun; Wang, Hongtao; Xie, Shengbo

2014-02-01

Aeolian sand transport results from interactions between the surface and the airflow above. Air density strongly constrains airflow characteristics and the resulting flow of sand, and therefore should not be neglected in sand transport models. In the present study, we quantify the influence of air density on the sand flow structure, sand transport rate, adobe abrasion profiles, and abrasion rate using a portable wind-tunnel in the field. For a given wind speed, the flow's ability to transport sand decreases at low air density, so total sand transport decreases, but the saltation height increases. Thus, the damage to human structures increases compared with what occurs at lower altitudes. The adobe abrasion rate by the cloud of blowing sand decreases exponentially with increasing height above the surface, while the wind erosion and dust emission intensity both increase with increasing air density. Long-term feedback processes between air density and wind erosion suggest that the development of low-altitude areas due to long-term deflation plays a key role in dust emission, and will have a profound significance for surface Aeolian processes and geomorphology.

Membranous appendices of spherosomes (oleosomes) : Possible role in fat utilization in germinating oil seeds.

Science.gov (United States)

Wanner, G; Theimer, R R

1978-01-01

Spherosomes (oleosomes) of cotyledons of rape (Brassica napus L.), sunflower (Helianthus annuus L.), and watermelon (Citrullus vulgaris, Schrad.) seedlings are delimited by a "half unit membrane" that appears to be continuous with each of the osmiophilic layers of a tripartite unit membrane forming a handlelike appendix of the spherosomes. Prior to any noticeable utilization of the spherosomal storage fat, ribosomes were found to be attached to these "handles". At later stages appendices of the spherosomes are smooth, showing a diameter of about 22 nm that greatly exceeds the thickness of any other unit membrane profiles identical in structure and diameter osomes appears to be continuous with the thick lipid layer of the handles. In intermediate stages of fat depletion the spherosomal bodies become invaginated with cytoplasmic material. Finally vesicles with cytoplasmic contents surrounded by a membrane with a typically thick lipid layer are left in the cells. Membrane profiles indentical in structure and diameter to the spherosomal appendices were also present in electron micrographs of the lipolytic membrane fraction recovered from sucrose density gradients after centrifugation of a microsomal cell fraction. The ultrastructural observations are taken for evidence that the spherosomal appendices represent the lipase-carrying membranes isolated previously (Theimer and Rosnitschek, 1978). A novel hypothesis for development and utilization of fat-storing spherosomes is also proposed.

Dynamics of organic carbon losses by water erosion after biocrust removal

Directory of Open Access Journals (Sweden)

Cantón Yolanda

2014-12-01

Full Text Available In arid and semiarid ecosystems, plant interspaces are frequently covered by communities of cyanobacteria, algae, lichens and mosses, known as biocrusts. These crusts often act as runoff sources and are involved in soil stabilization and fertility, as they prevent erosion by water and wind, fix atmospheric C and N and contribute large amounts of C to soil. Their contribution to the C balance as photosynthetically active surfaces in arid and semiarid regions is receiving growing attention. However, very few studies have explicitly evaluated their contribution to organic carbon (OC lost from runoff and erosion, which is necessary to ascertain the role of biocrusts in the ecosystem C balance. Furthermore, biocrusts are not resilient to physical disturbances, which generally cause the loss of the biocrust and thus, an increase in runoff and erosion, dust emissions, and sediment and nutrient losses. The aim of this study was to find out the influence of biocrusts and their removal on dissolved and sediment organic carbon losses. One-hour extreme rainfall simulations (50 mm h-1 were performed on small plots set up on physical soil crusts and three types of biocrusts, representing a development gradient, and also on plots where these crusts were removed from. Runoff and erosion rates, dissolved organic carbon (DOC and organic carbon bonded to sediments (SdOC were measured during the simulated rain. Our results showed different SdOC and DOC for the different biocrusts and also that the presence of biocrusts substantially decreased total organic carbon (TOC (average 1.80±1.86 g m-2 compared to physical soil crusts (7.83±3.27 g m-2. Within biocrusts, TOC losses decreased as biocrusts developed, and erosion rates were lower. Thus, erosion drove TOC losses while no significant direct relationships were found between TOC losses and runoff. In both physical crusts and biocrusts, DOC and SdOC concentrations were higher during the first minutes after runoff

Foothills Parkway Section 8B Final Environmental Report, Volume 4, Appendices E-I

Energy Technology Data Exchange (ETDEWEB)

Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

1999-07-01

In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NPS, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical, resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this ER, there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constructing Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER consists of Appendices E through I (all ecological survey reports), which are summarized individually in the sections that follow. The following conclusions result from the completion of these surveys and the ER impact analysis: (1) Forest clearing should be limited as much as possible; (2) Disturbed areas should be replanted with native trees; (3) Drainages should be bridged rather than leveled with cut and fill; (4) For areas of steep slopes and potential erosion

Developing maintainability for tokamak fusion power systems. Phase I report. Volume II. Appendices

International Nuclear Information System (INIS)

Zahn, H.S.

1977-10-01

This volume contains the following appendices: (1) baseline large module time estimates, (2) baseline intermediate module time estimates, (3) baseline small module time estimates, (4) alternate concept estimates, (5) maintenance equipment concepts, (6) additional reactor design definition, and (7) TOCOMO supplements

The history and assessment of effectiveness of soil erosion control measures deployed in Russia

Directory of Open Access Journals (Sweden)

Valentin Golosov

2013-09-01

Full Text Available Research activities aimed at design and application of soil conservation measures for reduction of soil losses from cultivated fields started in Russia in the last quarter of the 19th century. A network of "zonal agrofor-estry melioration experimental stations" was organized in the different landscape zones of Russia in the first half of the 20th century. The main task of the experiments was to develop effective soil conservation measures for Russian climatic,soil and land use conditions. The most widespread and large-scale introduction of coun-termeasures to cope with soil erosion by water and wind into agricultural practice supported by serious governmental investments took place during the Soviet Union period after the Second World War. After the Soviet Union collapse in 1991 ,general deterioration of the agricultural economy sector and the absence of investments resulted in cessation of organized soil conservation measures application at the nation-wide level. However, some of the long-term erosion control measures such as forest shelter belts, artificial slope terracing, water diversion dams above formerly active gully heads survived until the present. In the case study of sediment redistribution within the small cultivated catchment presented in this paper an attempt was made to evaluate average annual erosion rates on arable slopes with and without soil conservation measures for two time intervals. It has been found that application of conservation measures on cultivated slopes within the experimental part of the case study catchment has led to a decrease of average soil loss rates by at least 2. 5 2. 8 times. The figures obtained are in good agreement with previously published results of direct monitoring of snowmelt erosion rates, reporting approximately a 3 -fold decrease of average snowmelt erosion rates in the experimental sub-catchment compared to a traditionally cultivated control sub-catchment. A substantial decrease of soil

Gastric Mucosal Erosions - Radiologic evaluation -

International Nuclear Information System (INIS)

Kim, Seung Hyup

1985-01-01

70 cases of gastric mucosal erosions were diagnosed by double contrast upper gastrointestinal examinations and endoscopic findings. Analyzing the radiologic findings of these 70 cases of gastric mucosal erosions, the following results were obtained. 1. Among the total 70 cases, 65 cases were typical varioliform erosions showing central depressions and surrounding mucosal elevations. Remaining 5 cases were erosions of acute phase having multiple irregular depressions without surrounding elevations. 2. The gastric antrum was involved alone or in part in all cases. Duodenal bulb was involved with gastric antrum in 4 cases. 3. The majority of the cases had multiple erosions. There were only 2 cases of single erosion. 4. In 65 cases of varioliform erosions; 1) The diameter of the surrounding elevations varied from 3 to 20 mm with the majority (47 cases) between 6 and 10 mm. 2) In general, the surrounding elevations with sharp margin on double contrast films were also clearly demonstrated on compression films but those with faint margin were not. 3) The size of the central barium collections varied from pinpoint to 10 mm with the majority under 5 mm. The shape of the central barium collections in majority of the cases were round with a few cases of linear, triangular or star-shape. 5. In 5 cases of acute phase erosions; 1) All the 5 cases were females. 2) On double contrast radiography, all the cases showed multiple irregular depressed lesions without surrounding elevations. 3) 1 case had the history of hematemesis. 4) In 1 case, there was marked radiological improvement on follow-up study of 2 months interval. 6. In 23 cases, there were coexistent diseases with gastric mucosal erosions. These were 13 cases of duodenal bulb ulcers,7 cases of benign gastric ulcers and 3 others

Inflammatory markers in blood and serum tumor markers predict survival in patients with epithelial appendiceal neoplasms undergoing surgical cytoreduction and intraperitoneal chemotherapy.

Science.gov (United States)

Chua, Terence C; Chong, Chanel H; Liauw, Winston; Zhao, Jing; Morris, David L

2012-08-01

The study examines the role inflammatory and tumor markers as biomarkers to preoperatively predict outcome in patients with epithelial appendiceal neoplasm undergoing cytoreduction and intraperitoneal chemotherapy. Associations between baseline variables, tumor markers [CEA (carcinoembyronic antigen], CA125, CA199), inflammatory markers including neutrophils-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and C-reactive protein (CRP) with progression-free survival (PFS) and overall survival (OS) were examined in patients undergoing surgical cytoreduction and intraperitoneal chemotherapy for epithelial appendiceal neoplasm. A total of 174 patients with epithelial appendiceal neoplasm (low-grade pseudomyxoma, n = 117; appendiceal cancer, n = 57) underwent cytoreduction. On univariate analysis, all 3 inflammatory and tumor markers predicted for both PFS and OS, respectively; NLR ≤ 2.6 (P = 0.01, P = 0.002), PLR ≤ 166 (P = 0.006, P = 0.016), CRP ≤ 12.5 (P = 0.001, P = 0.008), CEA (P 37 (P = 0.003), and a CRP > 12.5 (P = 0.013). A higher peritoneal cancer index (PCI > 24) was associated with elevation in CEA > 12, CA125 > 39, CA199 > 37, PLR > 166 and CRP > 12. The tumor histologic subtype was associated with CA 199 levels. The results from this investigation suggest that preoperative inflammatory markers in blood and serologic tumor markers may predict outcomes and are associated with tumor biology in patients with epithelial appendiceal neoplasm undergoing cytoreduction and intraperitoneal chemotherapy treatment.

Comment Hobbes tente de rendre son matérialisme acceptable dans les appendices du Léviathan

Directory of Open Access Journals (Sweden)

Anne Staquet

2011-11-01

Full Text Available Le Léviathan de Hobbes [1651] a subi de nombreuses attaques, au point qu’il est jugé responsable de la grande peste de 1665 et de l’incendie de Londres l’année suivante et que le parlement ouvre une procédure contre l’ouvrage. Aussi, lorsqu’en 1666, Thomas Hobbes veut publier la traduction latine de ce livre, il y adjoint trois appendices. La version latine de l’œuvre est généralement jugée plus acceptable que le texte originaire anglais. En étudiant la manière dont Hobbes traite de son matérialisme dans ces appendices, je tente de montrer que les addenda latins ne constituent en aucune manière un retour en arrière du texte, mais que le philosophe enrobe simplement davantage des propos que, par ailleurs, il rend plus radicaux.Hobbes’s Leviathan [1651] has been critiqued so much that it was held responsible for the Great Plague of 1665 and the Fire of London during the following year, resulting in the Parliament instituting proceedings against the book. Therefore, when in 1666 Thomas Hobbes wanted to publish a Latin translation of this book, he added three appendices. Generally, the Latin version of the work is considered more acceptable than the English original text. By studying how Hobbes deals with his materialism in these appendices, I try to show that the Latin additions are in no way a reversal of the text, but that the philosopher simply veiled more propositions, while at the same time making them more radical.

Mobilization of dust and exfoliation of erosion product films in tokamaks

International Nuclear Information System (INIS)

Martynenko, Yu. V.; Nagel, M. Yu.

2012-01-01

The mobilization of dust (i.e., detachment and removal of dust grains from a substrate) and the exfoliation of a film of erosion products in tokamaks have been studied theoretically. The following mechanisms of dust mobilization have been taken into account: (i) sharp heating (thermal shock) as a result of, e.g., plasma disruption and edge instabilities; (ii) substrate vibrations; and (iii) gas and plasma flow (wind) action. The most effective mobilization takes place under the action of sharp heating. Power fluxes that are characteristic of edge instabilities can mobilize dust grains with dimensions within or even greater than 0.1–1 μm. The velocities of detached grains reach ν ∼ 100 m/s for heavy grains and up to ν ∼ 300 m/s for the light ones. Conditions favoring the exfoliation of a film of erosion products are determined. It is shown that exfoliation under the action of edge instabilities can take place at a film thickness of h > 1 μm. Under the action of thermal-shock-induced stresses, the exfoliated film flakes with a size ranging from fractions of a millimeter to several centimeters break into pieces.

Mobilization of dust and exfoliation of erosion product films in tokamaks

Energy Technology Data Exchange (ETDEWEB)

Martynenko, Yu. V.; Nagel, M. Yu. [National Research Centre Kurchatov Institute (Russian Federation)

2012-04-15

The mobilization of dust (i.e., detachment and removal of dust grains from a substrate) and the exfoliation of a film of erosion products in tokamaks have been studied theoretically. The following mechanisms of dust mobilization have been taken into account: (i) sharp heating (thermal shock) as a result of, e.g., plasma disruption and edge instabilities; (ii) substrate vibrations; and (iii) gas and plasma flow (wind) action. The most effective mobilization takes place under the action of sharp heating. Power fluxes that are characteristic of edge instabilities can mobilize dust grains with dimensions within or even greater than 0.1-1 {mu}m. The velocities of detached grains reach {nu} {approx} 100 m/s for heavy grains and up to {nu} {approx} 300 m/s for the light ones. Conditions favoring the exfoliation of a film of erosion products are determined. It is shown that exfoliation under the action of edge instabilities can take place at a film thickness of h > 1 {mu}m. Under the action of thermal-shock-induced stresses, the exfoliated film flakes with a size ranging from fractions of a millimeter to several centimeters break into pieces.

Coastal Erosion Control Methods

Science.gov (United States)

Greene, V.

2016-12-01

Coastal erosion is bad because the ecosystem there will be washed away and the animals could drown or be displaced and have to adapt to a new ecosystem that they are not prepared for. I'm interested in this problem because if there aren't beaches when I grow up I won't be able to do the things I would really like to do. I would like to be a marine biologist. Secondly, I don't want to see beach houses washed away. I would like to see people live in harmony with their environment. So, to study ways in which to preserve beaches I will make and use models that test different erosion controls. Two different ideas for erosion control I tested are using seaweed or a rock berm. I think the rock berm will work better than the model of seaweed because the seaweed is under water and the waves can carry the sand over the seaweed, and the rock berm will work better because the rocks will help break the waves up before they reach the shore and the waves can not carry the sand over the rocks that are above the water. To investigate this I got a container to use to model the Gulf of Mexico coastline. I performed several test runs using sand and water in the container to mimic the beach and waves from the Gulf of Mexico hitting the shoreline. I did three trials for the control (no erosion control), seaweed and a rock berm. Rock berms are a border of a raised area of rock. The model for seaweed that I used was plastic shopping bags cut into strips and glued to the bottom of my container to mimic seaweed. My results were that the control had the most erosion which ranged from 2.75 - 3 inches over 3 trials. The seaweed was a little better than the control but was very variable and ranged from 1.5 - 3 inches over 3 trials. The rock berm worked the best out of all at controlling erosion with erosion ranging from 1.5 - 2 inches. My hypothesis was correct because the rock berm did best to control erosion compared to the control which had no erosion control and the model with seaweed.

Developing maintainability for tokamak fusion power systems. Phase I report. Volume II. Appendices

Energy Technology Data Exchange (ETDEWEB)

Zahn, H.S.

1977-10-01

This volume contains the following appendices: (1) baseline large module time estimates, (2) baseline intermediate module time estimates, (3) baseline small module time estimates, (4) alternate concept estimates, (5) maintenance equipment concepts, (6) additional reactor design definition, and (7) TOCOMO supplements. (MOW)

Monthly Rainfall Erosivity Assessment for Switzerland

Science.gov (United States)

Schmidt, Simon; Meusburger, Katrin; Alewell, Christine

2016-04-01

Water erosion is crucially controlled by rainfall erosivity, which is quantified out of the kinetic energy of raindrop impact and associated surface runoff. Rainfall erosivity is often expressed as the R-factor in soil erosion risk models like the Universal Soil Loss Equation (USLE) and its revised version (RUSLE). Just like precipitation, the rainfall erosivity of Switzerland has a characteristic seasonal dynamic throughout the year. This inter-annual variability is to be assessed by a monthly and seasonal modelling approach. We used a network of 86 precipitation gauging stations with a 10-minute temporal resolution to calculate long-term average monthly R-factors. Stepwise regression and Monte Carlo Cross Validation (MCCV) was used to select spatial covariates to explain the spatial pattern of R-factor for each month across Switzerland. The regionalized monthly R-factor is mapped by its individual regression equation and the ordinary kriging interpolation of its residuals (Regression-Kriging). As covariates, a variety of precipitation indicator data has been included like snow height, a combination of hourly gauging measurements and radar observations (CombiPrecip), mean monthly alpine precipitation (EURO4M-APGD) and monthly precipitation sums (Rhires). Topographic parameters were also significant explanatory variables for single months. The comparison of all 12 monthly rainfall erosivity maps showed seasonality with highest rainfall erosivity in summer (June, July, and August) and lowest rainfall erosivity in winter months. Besides the inter-annual temporal regime, a seasonal spatial variability was detectable. Spatial maps of monthly rainfall erosivity are presented for the first time for Switzerland. The assessment of the spatial and temporal dynamic behaviour of the R-factor is valuable for the identification of more susceptible seasons and regions as well as for the application of selective erosion control measures. A combination with monthly vegetation

2016 wind energy observatory. Analysis of market, of jobs, and of the future of wind energy in France

International Nuclear Information System (INIS)

Wolff, Nicolas; Petit, Frederic; Autier, Emmanuel

2016-09-01

Illustrated by many graphs and tables of data, this publication first focuses on jobs in the wind energy sector as this sector keeps on growing (a stronger growth, a confirmed dynamics, a value chain in evolution, a diversity of actors all along the value chain) and keeps on creating jobs on the French territory (a fine meshing of the territory, a lever for regional development on the whole value chain). The second part focuses on the market and proposes an assessment of the wind energy market (a still growing market but still under objectives defined by the multi-annual energy programme or PPE, a competitive market which carries on its consolidation, a European growth with high discrepancies among countries) and a comment of the evolution of technologies (more powerful and more efficient machines, a concentrated technical offer, an always more important share in electricity production in France). The third part addresses the future of the sector by evoking adapted training programmes (training on all aspects, specialised training at all levels, a set of international training), research and development activities present on the whole French territory (a French sector strengthened by the offshore, new comers in the chain value), and the structuring of the sector with its multiple actors. Appendices respectively propose maps of locations of actors of the sector in French regions with additional information (number of jobs, main employer, distribution of jobs among the value chain, installed power, number of wind farms, main actors), and an analysis of the main characteristics of actors of different categories (developer or operator, machine manufacturer and maintenance activities, component manufacturer, civil or electric engineering and logistics, maintenance and subcontracting, engineering consulting and expertise)

RF model of the distribution system as a communication channel, phase 2. Volume 3: Appendices

Science.gov (United States)

Rustay, R. C.; Gajjar, J. T.; Rankin, R. W.; Wentz, R. C.; Wooding, R.

1982-01-01

Program documentation concerning the design, implementation, and verification of a computerized model for predicting the steady-state sinusoidal response of radial configured distribution feeders is presented in these appendices.

Report of the Bulletins and Orders Task Force. Volume II. Appendices

International Nuclear Information System (INIS)

1980-01-01

Appendices include: Office of Inspection and Enforcement bulletins; NRR status report on feedwater transients in BWR plants; orders on Babcock and Wilcox Company plants; letters lifting orders; letters issuing auxiliary feedwater system requirements; letter to licensees of all operating reactors, dated October 30, 1979 concerning short-term lessons learned requirements; and letters approving guidelines for preparation of small-break LOCA operating procedures

Risk of appendiceal endometriosis among women with deep-infiltrating endometriosis.

Science.gov (United States)

Moulder, Janelle K; Siedhoff, Matthew T; Melvin, Kathryn L; Jarvis, Elizabeth G; Hobbs, Kumari A; Garrett, Joanne

2017-11-01

To determine whether deep-infiltrating endometriosis (DE) carries an increased risk of appendiceal endometriosis (AppE) as compared with superficial endometriosis or no endometriosis. In a retrospective study, data were obtained by chart review of an internal database for women who underwent coincidental appendectomy during benign gynecologic surgery between July 2009 and February 2014 at a tertiary referral center in the USA. Univariate, bivariate, and regression analyses were performed. The primary exposure was surgically documented endometriosis (DE, superficial, or no endometriosis). The primary outcome was AppE. Endometriosis was diagnosed for 151 (38.2%) of 395 women; 82 (54.3%) had DE. The prevalence of AppE was 13.2% (52/395) overall; 8 (11.6%) of 69 women with superficial endometriosis and 32 (39.0%) of 82 with DE were affected. Frequency of AppE was increased among women with DE, abnormal appendix appearance, and surgical indication (all Pendometriosis, controlling for appendiceal appearance and surgical indication, and a 2.7-fold (95% CI 1.2-6.2) higher risk of AppE compared with those with superficial endometriosis. Women with DE have increased risk of AppE. Coincidental appendectomy should form part of complete endometriosis excision for these patients. © 2017 International Federation of Gynecology and Obstetrics.

Divertor erosion in DIII-D

International Nuclear Information System (INIS)

Whyte, D.G.; Bastasz, R.; Wampler, W.R.; Brooks, J.N.; West, W.P.; Wong, C.P.C.; Buzhinskij, O.I.; Opimach, I.V.

1998-08-01

Net erosion rates of carbon target plates have been measured in situ for the DIII-D lower divertor. The principal method of obtaining this data is the DiMES sample probe. Recent experiments have focused on erosion at the outer strike-point (OSP) of two divertor plasma conditions: attached (T e > 40 eV) ELMing plasmas, and detached (T e 2 . In this case, measurements and modeling agree for both gross and net carbon erosion, showing the near-surface transport and redeposition of the carbon is well understood. In the attached cases, physical sputtering (with enhancement from self-sputtering and oblique incidence) is dominant, and the effective sputtering yield, Y, is greater than 10%. In ELM-free discharges, the total OSP net erosion rate is equal to the rate of carbon accumulation in the core plasma. For the detached divertor cases, the cold incident plasma eliminates physical sputtering. Attempts to measure chemically eroded hydrocarbon molecules spectroscopically indicate an upper limit of Y ≤ 0.1% for the chemical sputtering yield. Net erosion is suppressed at the outer strike-point, which becomes a region of net redeposition (∼ 4 cm/exposure-year). The private flux wall is measured to be a region of net redeposition with dense, high neutral pressure, attached divertor plasmas. Leading edges intercepting parallel heat flux (∼ 50 MW/m 2 ) have very high net erosion rates at the OSP of an attached plasma (∼ 10 microm/s > 1,000x erosion rate of aligned surfaces). Leading edge erosion, and subsequent carbon redeposition, caused by tile gaps can account for half of the deuterium codeposition in the DIII-D divertor

C-reactive Protein may Predict the Recurrence of Appendicitis in Children Formerly with Appendiceal Mass after Successful Non-operative Treatment.

Science.gov (United States)

Chang, Yi-Jung; Chao, Hsun-Chin; Chen, Chyi-Liang; Chen, Shin-Yann; Yan, Dah-Chin; Tsai, Ming-Han

2017-08-01

This study identified factors associated with the recurrence of appendicitis in children with appendiceal masses after successful nonsurgical treatment. In this retrospective study, children who were diagnosed as having appendiceal masses after undergoing conservative treatment between 2000 and 2014 were enrolled and the medical records of those who did not undergo an interval appendectomy were reviewed. The clinical features and outcomes of patients with and those without recurrent appendicitis were compared. Regression analysis was used to identify risk factors of appendicitis recurrence. Seventy patients were included and successfully discharged after receiving nonsurgical treatment for appendiceal masses. Of the patients, 35 (50.0%) developed recurrent appendicitis and 85.7% (30/35) recurrences developed within 3 months. Multivariate analyses showed that patients with a higher serum C-reactive protein (CRP) level and peritonitis more frequently developed recurrence. The appendicitis recurrence rate was significantly higher in the patients with CRP levels of ≥103 mg/L with an odds ratio of 16.9 or in those with peritonitis with an odds ratio of 4.9. Children with appendiceal masses who develop peritonitis or have CRP levels of ≥103 mg/L have a higher recurrence rate of appendicitis and should undergo an interval appendectomy. Copyright © 2017. Published by Elsevier B.V.

A Curriculum Activities Guide to Water Pollution and Environmental Studies, Volume II - Appendices.

Science.gov (United States)

Hershey, John T., Ed.; And Others

This publication, Volume II of a two volume set of water pollution studies, contains seven appendices which support the studies. Appendix 1, Water Quality Parameters, consolidates the technical aspects of water quality including chemical, biological, computer program, and equipment information. Appendix 2, Implementation, outlines techniques…

Analysis and evaluation of GAVE chains. Part 3 of 3. Appendices; Analyse en evaluatie van GAVE-ketens. Deel 3 van 3. Appendices

Energy Technology Data Exchange (ETDEWEB)

Bosma, W.J.P. [Arthur D. Little International, Rotterdam (Netherlands)

1999-12-01

The final report (part 2) contains the detailed findings of the analysis, evaluation, and integration of Novem GAVE options and aims at the reader who is interested in the detailed findings, as well as an overview of the results. For readers who are mainly interested in the high-level results, and are comfortable with Dutch, there is a short text summary of our results, entitled 'Analyse en evaluatie van GAVE-ketens, management summary' (part 1). These appendices is for readers who are interested in the underlying data and detailed assumptions. 70 refs.

X-ray diagnosis of erosive gastritis

International Nuclear Information System (INIS)

Taskov, A.; Krastin, A.

1993-01-01

A series of 602 patients are studied according to a standard protocol including double contrast examination, taking films with dosed compression and complete filling (accordingly 3+3+1 radiographs). A barium suspension at concentration 200.0 BaSO 4 in 100 ml water is used as a positive contrast medium, and effervescent powder or pills - as a negative contrast. Erosive gastritis is diagnosed in 48 patients (7.9%) of which 38 present complete erosions (79.2%), 6 (12.6%) - incomplete, and 4 (8.3%) - mixed erosions. In 35 cases (72.9%) erosions are differentiated in double-contrast films, while in 21 (43.8%) - in those with compression. The advantage of the double contrast technique consists in visualization of erosions of the body of the stomach and discovering of incomplete erosions. In 483 patients a comparative assessment is done of the X-ray and endoscopic findings. There are recorded 5 false-positive and 25 false-negative radiological results. The sensitivity of the X-ray study in terms of erosive gastritis amounts to 59.7%. 15 refs., 4 figs. (orig.)

Mapping monthly rainfall erosivity in Europe

DEFF Research Database (Denmark)

Ballabio, C; Meusburger, K; Klik, A

2017-01-01

to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive...... and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part...... selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency...

Electric and Magnetic Fields (EMF) RAPID Program Engineering Project 8: FINAL REPORT, Evaluation of Field Reduction Technologies, Volume 1 (Report) and Volume 2 (Appendices)

Energy Technology Data Exchange (ETDEWEB)

Commonwealth Associates, Inc.; IIT Research Institute

1997-08-01

This draft report consists of two volumes. Volume 1, the main body, contains an introducto~ sectionj an overview of magnetic fields sectio~ and field reduction technology evaluation section. Magnetic field reduction methods are evalpated for transmission lines, distribution Iines,sulxtations, building wiring applkmd machinery, and transportation systems. The evaluation considers effectiveness, co% and other ftiors. Volume 2 contains five appendices, Append~ A presents magnetic field shielding information. Appendices B and C present design assumptions and magnetic field plots for transmission and distribution lines, respectively. Appendices D and E present cost estimate details for transmission and distribution limes, respectively.

Erosion can't hide from laser scanner

International Nuclear Information System (INIS)

Konstant, D.A.

1991-01-01

Particles of topsoil blown by wind will bounce along the soil surface and finally escape a field, leaving it less able to support crops. Water will wash away valuable topsoil and nutrients. And how rough the soil surface is influences whether the soil will erode. Until now, soil scientists have had no suitable technique to measure soil roughness - or microtopography - on the small scale. ARS soil scientists Joe M. Bradford and Chi-hua Huang, of the National Soil Erosion Research Laboratory in West Lafayette, Indiana, have developed a portable scanner that can. It measures the tiny ridges left in the soil by tilling or clods of soil particles that clump together naturally. What does the scanner do? It measures soil elevation by shining a low-power laser beam onto the surface and detecting the position of the laser spot reflected from the soil with a 35-mm camera. In place of film, the scanner camera uses electronic circuitry somewhat similar to that in a video camera to transmit the spot's position to a small computer about 30,000 times a minute. The laser and camera are mounted on the frame of a motor-driven carriage. The computer controls the carriage movement. At the end of a scan, a microtopographic map is stored in the computer. Scientists can analyze it immediately and can compare it to previous maps to see whether erosion has occurred

EFFECTS OF SLOPE SHAPES ON SOIL EROSION

Directory of Open Access Journals (Sweden)

Hüseyin ŞENSOY, Şahin PALTA

2009-01-01

Full Text Available Water is one of the most important erosive forces. A great number of factors also play a role in erosion process and slope characteristic is also one of them. The steepness and length of the slope are important factors for runoff and soil erosion. Another slope factor that has an effect on erosion is the shape of the slope. Generally, different erosion and runoff characteristics exist in different slopes which can be classified as uniform, concave, convex and complex shape. In this study, the effects of slope shape on erosion are stated and emphasized by taking similar researches into consideration.

Elevated temperature erosive wear of metallic materials

International Nuclear Information System (INIS)

Roy, Manish

2006-01-01

Solid particle erosion of metals and alloys at elevated temperature is governed by the nature of the interaction between erosion and oxidation, which, in turn, is determined by the thickness, pliability, morphology, adhesion characteristics and toughness of the oxide scale. The main objective of this paper is to critically review the present state of understanding of the elevated temperature erosion behaviour of metals and alloys. First of all, the erosion testing at elevated temperature is reviewed. This is followed by discussion of the essential features of elevated temperature erosion with special emphasis on microscopic observation, giving details of the erosion-oxidation (E-O) interaction mechanisms. The E-O interaction has been elaborated in the subsequent section. The E-O interaction includes E-O maps, analysis of transition criteria from one erosion mechanism to another mechanism and quantification of enhanced oxidation kinetics during erosion. Finally, the relevant areas for future studies are indicated. (topical review)

The backfilling and sealing of radioactive waste repositories. V. 2. Figure - Tables - Appendices

International Nuclear Information System (INIS)

1984-01-01

The two volumes of this report present a review study about backfilling and sealing of radioactive waste repositories in granites, argillaceous and salt formations. Volume 2 contains all the figures, table and appendices A detailed account of candidate backfill materials is given in a standardized format

[Mechanisms of grass in slope erosion control in Loess sandy soil region of Northwest China].

Science.gov (United States)

Zhao, Chun-Hong; Gao, Jian-En; Xu, Zhen

2013-01-01

By adopting the method of simulated precipitation and from the viewpoint of slope hydrodynamics, in combining with the analysis of soil resistance to erosion, a quantitative study was made on the mechanisms of grass in controlling the slope erosion in the cross area of wind-water erosion in Loess Plateau of Northwest China under different combinations of rainfall intensity and slope gradient, aimed to provide basis to reveal the mechanisms of vegetation in controlling soil erosion and to select appropriate vegetation for the soil and water conservation in Loess Plateau. The grass Astragalus adsurgens with the coverage about 40% could effectively control the slope erosion. This grass had an efficiency of more than 70% in reducing sediment, and the grass root had a greater effect than grass canopy. On bare slope and on the slopes with the grass plant or only the grass root playing effect, there existed a functional relation between the flow velocity on the slopes and the rainfall intensity and slope gradient (V = DJ(0.33 i 0.5), where V is flow velocity, D is the comprehensive coefficient which varies with different underlying surfaces, i is rainfall intensity, and J is slope gradient). Both the grass root and the grass canopy could markedly decrease the flow velocity on the slopes, and increase the slope resistance, but the effect of grass root in decreasing flow velocity was greater while the effect in increasing resistance was smaller than that of grass canopy. The effect of grass root in increasing slope resistance was mainly achieved by increasing the sediment grain resistance, while the effect of canopy was mainly achieved by increasing the slope form resistance and wave resistance. The evaluation of the soil resistance to erosion by using a conceptual model of sediment generation by overland flow indicated that the critical shear stress value of bare slope and of the slopes with the grass plant or only the grass root playing effect was 0.533, 1.672 and 0

Assessment and management of dental erosion.

Science.gov (United States)

Wang, Xiaojie; Lussi, Adrian

2010-07-01

Studies have shown a growing trend toward increasing prevalence of dental erosion, associated with the declining prevalence of caries disease in industrialized countries. Erosion is an irreversible chemical process that results in tooth substance loss and leaves teeth susceptible to damage as a result of wear over the course of an individual's lifetime. Therefore, early diagnosis and adequate prevention are essential to minimize the risk of tooth erosion. Clinical appearance is the most important sign to be used to diagnose erosion. The Basic Erosive Wear Examination (BEWE) is a simple method to fulfill this task. The determination of a variety of risk and protective factors (patient-dependent and nutrition-dependent factors) as well as their interplay are necessary to initiate preventive measures tailored to the individual. When tooth loss caused by erosive wear reaches a certain level, oral rehabilitation becomes necessary. Copyright 2010 Elsevier Inc. All rights reserved.

Monitoring Soil Erosion on a Burned Site in the Mojave-Great Basin Transition Zone: Final Report for the Jacob Fire Site

Energy Technology Data Exchange (ETDEWEB)

Miller, Julianne [DRI; Etyemezian, Vic [DRI; Cablk, Mary E. [DRI; Shillito, Rose [DRI; Shafer, David [DOE Grand Junction, Colorado

2013-06-01

A historic return interval of 100 years for large fires in the U.S. southwestern deserts is being replaced by one where fires may reoccur as frequently as every 20 to 30 years. The shortened return interval, which translates to an increase in fires, has implications for management of Soil Corrective Action Units (CAUs) and Corrective Action Sites (CASs) for which the Department of Energy, National Nuclear Security Administration Nevada Field Office has responsibility. A series of studies was initiated at uncontaminated analog sites to better understand the possible impacts of erosion and transport by wind and water should contaminated soil sites burn. The first of these studies was undertaken at the Jacob Fire site approximately 12 kilometers (7.5 miles) north of Hiko, Nevada. A lightning-caused fire burned approximately 200 hectares during August 6-8, 2008. The site is representative of a transition between Mojave and Great Basin desert ecoregions on the Nevada National Security Site (NNSS), where the largest number of Soil CAUs/CASs are located. The area that burned at the Jacob Fire site was primarily a Coleogyne ramosissima (blackbrush) and Ephedra nevadensis (Mormon tea) community, also an abundant shrub assemblage in the similar transition zone on the NNSS. This report summarizes three years of measurements after the fire. Seven measurement campaigns at the Jacob Fire site were completed. Measurements were made on burned ridge (upland) and drainage sites, and on burned and unburned sites beneath and between vegetation. A Portable In-Situ Wind Erosion Lab (PI-SWERL) was used to estimate emissions of suspended particles at different wind speeds. Context for these measurements was provided through a meteorological tower that was installed at the Jacob Fire site to obtain local, relevant environmental parameters. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Runoff and water erosion were

Pyrogenic Carbon Erosion: Implications for Stock and Persistence of Pyrogenic Carbon in Soil

Directory of Open Access Journals (Sweden)

Rebecca B. Abney

2018-03-01

Full Text Available Pyrogenic carbon (PyC constitutes an important pool of soil organic matter (SOM, particularly for its reactivity and because of its assumed long residence times in soil. In the past, research on the dynamics of PyC in the soil system has focused on quantifying stock and mean residence time (MRT of PyC in soil, as well as determining both PyC stabilization mechanisms and loss pathways. Much of this research has focused on decomposition as the most important loss pathway for PyC from soil. However, the low density of PyC and its high concentration on the soil surface after fire indicates that a significant proportion of PyC formed or deposited on the soil surface is likely laterally transported away from the site of production by wind and water erosion. Here, we present a synthesis of available data and literature to compare the magnitude of the water-driven erosional PyC flux with other important loss pathways, including leaching and decomposition, of PyC from soil. Furthermore, we use a simple first-order kinetic model of soil PyC dynamics to assess the effect of erosion and deposition on residence time of PyC in eroding landscapes. Current reports of PyC MRT range from 250 to 660 years. Using a specific example-based model system, we find that ignoring the role of erosion may lead to the under- or over-estimation of PyC MRT on the centennial time scale. Furthermore, we find that, depending on the specific landform positions, timescales considered, and initial concentrations of PyC in soil, ignoring the role of erosion in distributing PyC across a landscape can lead to discrepancies in PyC concentrations on the order of several 100 g PyC m−2. Erosion is an important PyC flux that can act as a significant control on the stock and residence time of PyC in the soil system.

Pyrogenic carbon erosion: implications for stock and persistence of pyrogenic carbon in soil

Science.gov (United States)

Abney, Rebecca B.; Berhe, Asmeret Asefaw

2018-03-01

Pyrogenic carbon (PyC) constitutes an important pool of soil organic matter, particularly for its reactivity and because of its assumed long residence times in soil. In the past, research on the dynamics of PyC in the soil system has focused on quantifying stock and mean residence time of PyC in soil, as well as determining both PyC stabilization mechanisms and loss pathways. Much of this research has focused on decomposition as the most important loss pathway for PyC from soil. However, the low density of PyC and its high concentration on the soil surface after fire indicates that a significant proportion of PyC formed or deposited on the soil surface is likely laterally transported away from the site of production by wind and water erosion. Here, we present a synthesis of available data and literature to compare the magnitude of the water-driven erosional PyC flux with other important loss pathways, including leaching and decomposition, of PyC from soil. Furthermore, we use a simple first-order kinetic model of soil PyC dynamics to assess the effect of erosion and deposition on residence time of PyC in eroding landscapes. Current reports of PyC mean residence time (MRT) range from 250 to 660 years. Using a specific example-based model system, we find that ignoring the role of erosion may lead to the under- or over-estimation of PyC MRT on the centennial time scale. Furthermore, we find that, depending on the specific landform positions, timescales considered, and initial concentrations of PyC in soil, ignoring the role of erosion in distributing PyC across a landscape can lead to discrepancies in PyC concentrations on the order of several hundred g PyC m-2. Erosion is an important PyC flux that can act as a significant control on the stock and residence time of PyC in the soil system.

Soil erosion processes on sloping land using REE tracer

International Nuclear Information System (INIS)

Shen Zhenzhou; Liu Puling; Yang Mingyi; Lian Zhenlong; Ju Tongjun; Yao Wenyi; Li Mian

2007-01-01

Sheet erosion is the main performance in the slope soil erosion process at the primary stage of natural rainfall. For three times of rainfall during experiment, the ratios of sheet erosion to total erosion account for 71%, 48% and 49% respectively, which showed that the sloping erosion was still at the primary stage from sheet erosion to rill erosion. With the rainfall going, the rill erosion amount increase. It showed that soil erosion was changing from sheet erosion to rill erosion. The sources of sediment from different sections of the plot were analyzed, and the results indicated that whatever the sheet erosion changed, the ratio erosion of upper part of surface soil was always lower than 10%. Sheet erosion came mainly from the lower section of surface soil. With the ratios to the amount of total rill erosion changes, the rill erosion amount of each section regularly changes too. The general conclusion is that when the rainfall ends, relative erosion of different slope element to the foot of slope is: 1 meter away accounts for 16%, 2-4 meters away is 6% and 5-9 meters away is 3%. The ratio of rill erosion amount of these three slope element is 5:2:1, which shows the rill erosion amount are mainly from the slope element of 4 meters from the foot of slope. (authors)

Soil Erosion and Agricultural Sustainability

Science.gov (United States)

Montgomery, D. R.

2009-04-01

Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by up to several orders of magnitude, similar global distributions of soil production and geological erosion rates suggest an approximate balance. Net soil erosion rates in conventionally plowed fields on the order of 1 mm/yr can erode typical hillslope soil profiles over centuries to millennia, time-scales comparable to the longevity of major civilizations. Well-documented episodes of soil loss associated with agricultural activities date back to the introduction of erosive agricultural methods in regions around the world, and stratigraphic records of accelerated anthropogenic soil erosion have been recovered from lake, fluvial, and colluvial stratigraphy, as well as truncation of soil stratigraphy (such as truncated A horizons). A broad convergence in the results from studies based on various approaches employed to study ancient soil loss and rates of downstream sedimentation implies that widespread soil loss has accompanied human agricultural intensification in examples drawn from around the world. While a broad range of factors, including climate variability and society-specific social and economic contexts — such as wars or colonial relationships — all naturally influence the longevity of human societies, the ongoing loss of topsoil inferred from studies of soil erosion rates in conventional agricultural systems has obvious long-term implications for agricultural sustainability. Consequently, modern agriculture — and therefore global society — faces a fundamental question over the upcoming centuries. Can an agricultural system

Medication-related dental erosion: a review.

Science.gov (United States)

Thomas, Manuel S; Vivekananda Pai, A R; Yadav, Amit

2015-10-01

Dental erosion has become a major problem that affects the long-term health of the dentition. Among the various potential causes for erosive tooth wear, the different drugs prescribed for patients may be overlooked. Several therapeutic medications can directly or indirectly be associated with dental erosion. It is the responsibility of oral health providers to make both patients and colleagues aware of drugs that may contribute to this condition. Therefore, the purpose of this discussion is to provide an overview of the various therapeutic medications that can be related to tooth erosion. The authors also include precautionary measures-summarized as The 9 Rs-to avoid or at least reduce medication-induced erosion.

Composition of enamel pellicle from dental erosion patients.

Science.gov (United States)

Carpenter, G; Cotroneo, E; Moazzez, R; Rojas-Serrano, M; Donaldson, N; Austin, R; Zaidel, L; Bartlett, D; Proctor, G

2014-01-01

Oral health is dependent upon a thin mobile film of saliva on soft and hard tissues. Salivary proteins adhere to teeth to form the acquired enamel pellicle which is believed to protect teeth from acid erosion. This study investigated whether patients suffering diet-induced dental erosion had altered enamel pellicles. Thirty patients suffering erosion were compared to healthy age-matched controls. Subjects wore a maxillary splint holding hydroxyapatite and human enamel blocks for 1 h. The acquired enamel pellicle was removed from the blocks and compared to the natural incisor pellicle. Basic Erosive Wear Examination scores confirmed that dental erosion was present in erosion patients and absent from healthy age-matched controls. Erosion patients had half the amount of proteins (BCA assay) within the acquired pellicle forming on splint blocks compared to normal controls (p erosion patients (p erosion patients and healthy controls. In summary, the formation of new acquired pellicles on surfaces was reduced in erosion patients, which may explain their greater susceptibility to acid erosion of teeth. © 2014 S. Karger AG, Basel.

Master plan study - District heating Sillamaee municipality. Estonia. Final report. Appendices for chapter 9

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

The appendices to the final report on the master plan study on district heating in the municipality in Estonia, chapter nine, gives data related to general economic assumptions for financial and economic calculations, fuel consumption, financing, prices, fuel consumption. (ARW)

76 FR 64112 - Privacy Act of 1974; Privacy Act System of Records Appendices

Science.gov (United States)

2011-10-17

... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-091)] Privacy Act of 1974; Privacy Act...: Revisions of NASA Appendices to Privacy Act System of Records. SUMMARY: Notice is hereby given that NASA is... Privacy Act of 1974. This notice publishes those amendments as set forth below under the caption...

The water erosion processes in the retreat erosive of cliff on soft rocks in the province of Cadiz (Spain)

International Nuclear Information System (INIS)

Rendon Aragon, J. J.; Gracia Prieto, F. J.; Rio Rodriguez, L. del

2009-01-01

The littoral cliffs on soft materials of the Atlantic Cadiz coast show an important activity of the fresh water erosion processes, sometimes even more significant than the marine erosion processes. The connection of the lower cliffs with sandy beaches favours aeolian sand invasion, which fills previous rills and reduces the water erosion intensity by increasing infiltration. Cliff retreat and rill erosion measurement by using erosion sticks has shown very variables values, most of them higher than the estimated error of the employed methods. This indicates the existence of other factors influencing the distribution of water erosion processes along these cliffs, which have to be studied through different techniques. (Author) 5 refs.

Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA

Science.gov (United States)

Schoellhamer, David H.; Manning, Andrew J.; Work, Paul A.

2017-01-01

Erodibility of cohesive sediment in the Sacramento-San Joaquin River Delta (Delta) was investigated with an erosion microcosm. Erosion depths in the Delta and in the microcosm were estimated to be about one floc diameter over a range of shear stresses and times comparable to half of a typical tidal cycle. Using the conventional assumption of horizontally homogeneous bed sediment, data from 27 of 34 microcosm experiments indicate that the erosion rate coefficient increased as eroded mass increased, contrary to theory. We believe that small erosion depths, erosion rate coefficient deviation from theory, and visual observation of horizontally varying biota and texture at the sediment surface indicate that erosion cannot solely be a function of depth but must also vary horizontally. We test this hypothesis by developing a simple numerical model that includes horizontal heterogeneity, use it to develop an artificial time series of suspended-sediment concentration (SSC) in an erosion microcosm, then analyze that time series assuming horizontal homogeneity. A shear vane was used to estimate that the horizontal standard deviation of critical shear stress was about 30% of the mean value at a site in the Delta. The numerical model of the erosion microcosm included a normal distribution of initial critical shear stress, a linear increase in critical shear stress with eroded mass, an exponential decrease of erosion rate coefficient with eroded mass, and a stepped increase in applied shear stress. The maximum SSC for each step increased gradually, thus confounding identification of a single well-defined critical shear stress as encountered with the empirical data. Analysis of the artificial SSC time series with the assumption of a homogeneous bed reproduced the original profile of critical shear stress, but the erosion rate coefficient increased with eroded mass, similar to the empirical data. Thus, the numerical experiment confirms the small-depth erosion hypothesis. A linear

Recommendations for a Department of Energy Nuclear Energy R and D Agenda Volume 2 Appendices

International Nuclear Information System (INIS)

1997-01-01

The current US nuclear energy policy is primarily formulated as part of the nation's overall energy policy. In addition, nuclear energy policy is impacted by other US policies, such as those for defense and environment, and by international obligations through their effects on nuclear weapons dismantlement and stewardship, continued reliance on space and naval nuclear power sources, defense waste cleanup, and on nuclear nonproliferation. This volume is composed of the following appendices: Appendix 1--Objectives of the Federal Government Nuclear Energy Related Policies and Research and Development Programs; Appendix 2--Nuclear Energy and Related R and D in the US; Appendix 3--Summary of Issues That Drive Nuclear Energy Research and Development; Appendix 4: Options for Policy and Research and Development; Appendix 5--Pros and Cons of Objectives and Options; and Appendices 6--Recommendations

Recommendations for a Department of Energy Nuclear Energy R and D Agenda Volume 2 Appendices

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

The current US nuclear energy policy is primarily formulated as part of the nation`s overall energy policy. In addition, nuclear energy policy is impacted by other US policies, such as those for defense and environment, and by international obligations through their effects on nuclear weapons dismantlement and stewardship, continued reliance on space and naval nuclear power sources, defense waste cleanup, and on nuclear nonproliferation. This volume is composed of the following appendices: Appendix 1--Objectives of the Federal Government Nuclear Energy Related Policies and Research and Development Programs; Appendix 2--Nuclear Energy and Related R and D in the US; Appendix 3--Summary of Issues That Drive Nuclear Energy Research and Development; Appendix 4: Options for Policy and Research and Development; Appendix 5--Pros and Cons of Objectives and Options; and Appendices 6--Recommendations.

Environment, Health, and Safety | NREL

Science.gov (United States)

-Wide Environmental Assessment 2014 (DOE/EA-1914). Final EA and FONSI Appendices. Natural and Cultural property, and the environment. View the Environmental Stewardship, Health, Safety, and Quality Management Environmental Assessment 2014. Final EA and FONSI Appendices. Download the National Wind Technology Center Site

Robotic weld overlay coatings for erosion control

Science.gov (United States)

The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB's.

Regionalization of monthly rainfall erosivity patternsin Switzerland

Science.gov (United States)

Schmidt, Simon; Alewell, Christine; Panagos, Panos; Meusburger, Katrin

2016-10-01

One major controlling factor of water erosion is rainfall erosivity, which is quantified as the product of total storm energy and a maximum 30 min intensity (I30). Rainfall erosivity is often expressed as R-factor in soil erosion risk models like the Universal Soil Loss Equation (USLE) and its revised version (RUSLE). As rainfall erosivity is closely correlated with rainfall amount and intensity, the rainfall erosivity of Switzerland can be expected to have a regional characteristic and seasonal dynamic throughout the year. This intra-annual variability was mapped by a monthly modeling approach to assess simultaneously spatial and monthly patterns of rainfall erosivity. So far only national seasonal means and regional annual means exist for Switzerland. We used a network of 87 precipitation gauging stations with a 10 min temporal resolution to calculate long-term monthly mean R-factors. Stepwise generalized linear regression (GLM) and leave-one-out cross-validation (LOOCV) were used to select spatial covariates which explain the spatial and temporal patterns of the R-factor for each month across Switzerland. The monthly R-factor is mapped by summarizing the predicted R-factor of the regression equation and the corresponding residues of the regression, which are interpolated by ordinary kriging (regression-kriging). As spatial covariates, a variety of precipitation indicator data has been included such as snow depths, a combination product of hourly precipitation measurements and radar observations (CombiPrecip), daily Alpine precipitation (EURO4M-APGD), and monthly precipitation sums (RhiresM). Topographic parameters (elevation, slope) were also significant explanatory variables for single months. The comparison of the 12 monthly rainfall erosivity maps showed a distinct seasonality with the highest rainfall erosivity in summer (June, July, and August) influenced by intense rainfall events. Winter months have the lowest rainfall erosivity. A proportion of 62 % of

Worldwide status of energy standards for buildings: Appendices

Energy Technology Data Exchange (ETDEWEB)

Janda, K.B.; Busch, J.F.

1993-02-01

This informal survey was designed to gain information about the worldwide status of energy efficiency standards for buildings, particularly non-residential buildings such as offices, schools, and hotels. The project has three goals: 1. To understand and learn from the experience of countries with existing building energy standards; 2. To locate areas where these lessons might be applied and energy standards might be effectively proposed and developed; and 3. To share the information gathered with all participating countries. These appendices include the survey cover letter, the survey, and the details of selected energy standards in 35 countries, thus providing supporting material for the authors` article of the same title.

Erosion resistance comparison of alternative surface treatments

Science.gov (United States)

Česánek, Z.; Schubert, J.; Houdková, Š.

2017-05-01

Erosion is a process characterized by the particle separation and the damage of component functional surfaces. Thermal spraying technology HP/HVOF (High Pressure / High Velocity Oxygen Fuel) is commonly used for protection of component surfaces against erosive wear. Alloy as well as cermet based coatings meet the requirements for high erosion resistance. Wear resistance is in many cases the determining property of required component functioning. The application suitability of coating materials is particularly influenced by different hardness. This paper therefore presents an erosion resistance comparison of alloy and cermet based coatings. The coatings were applied on steel substrates and were subjected to the erosive test using the device for evaluation of material erosion resistance working on the principle of centrifugal erodent flow. Abrasive sand Al2O3 with grain size 212-250 μm was selected as an erosive material. For this purpose, the specimens were prepared by thermal spraying technology HP/HVOF using commercially available powders Stellite 6, NiCrBSi, Cr3C2-25%NiCr, Cr3C2-25%CoNiCrAlY, Hastelloy C-276 and experimental coating TiMoCN-29% Ni. Erosion resistance of evaluated coatings was compared with erosive resistance of 1.4923 high alloyed steel without nitridation and in nitrided state and further with surface treatment using technology PVD. According to the evaluation, the resulting erosive resistance depends not only on the selected erodent and surface protection, but also on the erodent impact angle.

The erosion and erosion products of tungsten and carbon based materials bombarded by high energy pulse electron beam

International Nuclear Information System (INIS)

Liu Xiang; Zhang Fu; Xu Zengyu; Liu Yong; Yoshida, N.; Noda, N.

2002-01-01

In this paper, the erosion behaviors and erosion products of tungsten and some carbon based materials, such as graphite, C/C composite and B 4 C/Cu functionally graded material, were investigated by using a pulse electron beam to simulate the vertical displacement events (VDE) process. The authors will focus on the forms and differences of erosion products among these testing materials, and make clear to their erosion mechanisms

Auto consolidated cohesive sediments erosion

International Nuclear Information System (INIS)

Ternat, F.

2007-02-01

Pollutants and suspended matters of a river can accumulate into the sedimentary column. Once deposited, they are submitted to self-weight consolidation processes, ageing and burying, leading to an increase of their erosion resistance. Pollutant fluxes can be related to sedimentary fluxes, determined by threshold laws. In this work, an erosion threshold model is suggested by introducing a cohesion force into the usual force balance. A model of cohesion is developed on the basis of interactions between argillaceous cohesive particles (clays), particularly the Van der Waals force, whose parameterization is ensured by means of granulometry and porosity. Artificial erosion experiments were performed in a recirculating erosion flume with natural cored sediments where critical shear stress measurements were performed. Other analyses provided granulometry and porosity. The results obtained constitute a good database for the literature. The model is then applied to the experimental conditions and gives good agreement with measurements. An example of the accounting for self-weight consolidation processes is finally suggested, before finishing on a Mohr like diagram dedicated to soft cohesive sediment erosion. (author)

Dynamic Analysis of Soil Erosion in Songhua River Watershed

Science.gov (United States)

Zhang, Yujuan; Li, Xiuhai; Wang, Qiang; Liu, Jiang; Liang, Xin; Li, Dan; Ni, Chundi; Liu, Yan

2018-01-01

In this paper, based on RS and GIS technology and Revised Universal Soil Loss Equation (RUSLE), the soil erosion dynamic changes during the two periods of 1990 and 2010 in Bin County was analyzed by using the Landsat TM data of the two periods, so as to reveal the soil erosion spatial distribution pattern and spatial and temporal dynamic evolution rule in the region. The results showed that: the overall patterns of soil erosion were basically the same in both periods, mainly featuring slight erosion and mild erosion, with the area proportions of 80.68% and 74.71% respectively. The slight and extremely intensive erosion changing rates showed a narrowing trend; mild, moderate and intensive erosion was increasing, with a trend of increased soil erosion; mild and intensive erosion were developing towards moderate erosion and moderate and extremely intensive erosion were progressing towards intensive erosion.

Case-study application of venture analysis: the integrated energy utility. Volume 3. Appendices

Energy Technology Data Exchange (ETDEWEB)

Fein, E; Gordon, T J; King, R; Kropp, F G; Shuchman, H L; Stover, J; Hausz, W; Meyer, C

1978-11-01

The appendices for a case-study application of venture analysis for an integrated energy utility for commercialization are presented. The following are included and discussed: utility interviews; net social benefits - quantitative calculations; the financial analysis model; market penetration decision model; international district heating systems; political and regulatory environment; institutional impacts.

New insights into the wind-dust relationship in sandblasting and direct aerodynamic entrainment from wind tunnel experiments

KAUST Repository

Parajuli, Sagar Prasad; Zobeck, Ted M.; Kocurek, Gary; Yang, Zong-Liang; Stenchikov, Georgiy L.

2016-01-01

Numerous parameterizations have been developed for predicting wind erosion, yet the physical mechanism of dust emission is not fully understood. Sandblasting is thought to be the primary mechanism, but recent studies suggest that dust emission by direct aerodynamic entrainment can be significant under certain conditions. In this work, using wind tunnel experiments, we investigated some of the lesser understood aspects of dust emission in sandblasting and aerodynamic entrainment for three soil types, namely clay, silty clay loam, and clay loam. First, we explored the role of erodible surface roughness on dust emitted by aerodynamic entrainment. Second, we compared the emitted dust concentration in sandblasting and aerodynamic entrainment under a range of wind friction velocities. Finally, we explored the sensitivity of emitted dust particle size distribution (PSD) to soil type and wind friction velocity in these two processes. The dust concentration in aerodynamic entrainment showed strong positive correlation, no significant correlation, and weak negative correlation, for the clay, silty clay loam, and clay loam, respectively, with the erodible soil surface roughness. The dust in aerodynamic entrainment was significant constituting up to 28.3, 41.4, and 146.4% compared to sandblasting for the clay, silty clay loam, and clay loam, respectively. PSD of emitted dust was sensitive to soil type in both sandblasting and aerodynamic entrainment. PSD was sensitive to the friction velocity in aerodynamic entrainment but not in sandblasting. Our results highlight the need to consider the details of sandblasting and direct aerodynamic entrainment processes in parameterizing dust emission in global/regional climate models.

New insights into the wind-dust relationship in sandblasting and direct aerodynamic entrainment from wind tunnel experiments