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1

Author's personal copy Revisiting dirt cracking as a physical weathering process in warm deserts  

E-print Network

- envisioned dirt-cracking wedging process starts with calcium carbonate precipitating in ssures less than 5 m pressure to widen and deepen the ssure, allowing the carbonate precipitation process to penetrate evenAuthor's personal copy Revisiting dirt cracking as a physical weathering process in warm deserts

Dorn, Ron

2

Weather Information Processing  

NASA Technical Reports Server (NTRS)

Science Communications International (SCI), formerly General Science Corporation, has developed several commercial products based upon experience acquired as a NASA Contractor. Among them are METPRO, a meteorological data acquisition and processing system, which has been widely used, RISKPRO, an environmental assessment system, and MAPPRO, a geographic information system. METPRO software is used to collect weather data from satellites, ground-based observation systems and radio weather broadcasts to generate weather maps, enabling potential disaster areas to receive advance warning. GSC's initial work for NASA Goddard Space Flight Center resulted in METPAK, a weather satellite data analysis system. METPAK led to the commercial METPRO system. The company also provides data to other government agencies, U.S. embassies and foreign countries.

1991-01-01

3

Weathering  

NSDL National Science Digital Library

This course handout covers the processes and effects of weathering. The purpose of this handout is to contrast weathering and erosion, contrast and discuss chemical and mechanical weathering, list the products resulting from the chemical weathering of igneous rocks, and list and discuss the factors that influence the type and rate of rock weathering. Many photographs accompany this summary which depict weathered landscapes. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Gore, Pamela

1995-08-29

4

Space Weathering Processes on Mercury  

NASA Technical Reports Server (NTRS)

Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will incur the effects of space weathering. These weathering processes are capable of both creating regolith and altering its optical properties. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes as well as the products of those processes. It should be possible to observe the effects of these differences in Vis/NIR spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the iron content of the Mercurian surface. Theoretical and experimental work has been undertaken in order to better understand these consequences.

Noble, S. K.; Pieters, C. M.

2002-01-01

5

Weather  

NSDL National Science Digital Library

Have you ever wondered how the weather man, or meteorolgist, on TV knows what to say about tomorrow\\'s weather? It\\'s because they have certain tools that they use that help them predict what the weather will be. Throughout this school year you are going to be making tools and predicting weather just like a meterorologist! Task You are going to be weather forcasters! You are going to record and track weather patterns throughout the year. You will also use weather tools to make predictions about the weather like real weather forecasters! The Process 1. First we need to learn a little bit about weather so ...

Williams, Ms.

2005-10-25

6

Space Weather: Physics and Effects  

NASA Astrophysics Data System (ADS)

With the launching of Sputnik, Explorer 1, and the other early satellites, the new discipline of space physics was born, about 50 years ago. Although earlier ground-based observations had provided strong hints about the nature of our space environment above the upper atmosphere, those early satellites initiated a series of surprises and discoveries, including Van Allen's discovery of the Earth's radiation belts. Young scientists were attracted to this new field, and it grew quickly. When the Journal of Geophysical Research was divided into two sections, in 1964, one section was devoted to space physics. The field explored not only new regions of space but also a new state of matter: the rarefied, fully ionized plasma that fills space and interacts intimately with magnetic fields.

Hughes, W. Jeffrey

2009-03-01

7

Physical weathering and modification of a rhyolitic hyaloclastite in Iceland  

NASA Astrophysics Data System (ADS)

Fragmental volcanic glass or `hyaloclastite' is a common glaciovolcanic eruption product that is formed in large abundance during basaltic, andesitic and rhyolitic subglacial eruptions. The physical weathering of rhyolitic hyaloclastites differs notably from basaltic hyaloclastites due to differences in cementation and edifice consolidation. As rhyolitic glasses are also much rarer, comparatively little is known about their physical weathering and fracturing characteristics. In the presented study, we provide a process-oriented analysis of the physical modification of subglacially erupted rhyolitic hyaloclastites from the Bláhnúkur edifice in Torfajökull (Iceland). Frost weathering experiments were performed to determine how vesicular glass particles fragment to finer particle sizes. The surficial porosity of the glass drives such frost weathering through the process of pore pressurisation and was quantified using high-pressure mercury intrusion. Uniaxial compression experiments were carried out to understand how the glass structure responds to the application of external stress. The observed fracturing in both experimental treatments was found to adhere to fractal statistics, which allowed the compression experiments to be used in conjunction with the frost weathering experiments for inferring the fracturing characteristics of rhyolitic volcanic glasses. Transport processes by wind and gravity were simulated by long-duration abrasion experiments in rock tumblers (through granular avalanching), but these low-energy particle interactions were not found to significantly abrade particles. A notable result from our fragmentation experiments was the production of <10 ?m particles. This size range is considered respirable and illustrates how physical weathering can continuously create potentially harmful ash textures; a process which is often overlooked in health hazard assessments after volcanic eruptions. Fragmentation by post-eruptive weathering can lead to overestimations of the fine ash fraction produced by syneruptive fragmentation and granulometric studies therefore need to be appreciative of the effects of such secondary fracturing processes.

de Vet, S. J.; Mittelmeijer-Hazeleger, M. C.; Braakhekke, J. J. M.; Cammeraat, L. H.

2014-06-01

8

Quantifying the physical and chemical mass transfer processes for the fate and transport of Co(II)EDTA in a partially-weathered limestone-shale saprolite.  

PubMed

The objective of the research is to quantify the relative contributions of physical and chemical mass transfer to the movement of Co(II/III)EDTA (chelates of Cobalt and Ethylene Diamine Tetraacetic Acid or EDTA) through a limestone-shale saprolite soil. Saprolite is a collective term referring to partially-weathered bedrock. It exists extensively in the subsurface. Because the parent bedding structures are maintained during the weathering process, saprolite soils are characterized by intensive fractures and secondary deposits of minerals such as Al-, Fe- and Mn-oxides on the fracture surfaces. Movement of reactive species through the soils may be influenced by diffusion into the rock matrix, a physical mass transfer (PMT) process, and interfacial chemical reactions, a chemical mass transfer (CMT) process. The PMT and CMT processes are phenomenologically similar but mechanistically different. In this research, previous laboratory observations from a Br and Co(II)EDTA tracer injection into an undisturbed saprolite soil column were used. Mechanistic reactive transport models were formulated to quantify the PMT and CMT processes. The PMT process was independently characterized by using the non-reactive tracer Br. Model parameters thus obtained were subsequently used as constraints to quantify the CMT processes involving Co(II)EDTA and its oxidation product Co(III)EDTA. Our calculations indicated that the PMT rates of the less reactive Co(III)EDTA were comparable with their theoretical CMT rates. In contrast, for the more reactive species Co(II)EDTA, CMT rates are higher than PMT rates. Evaluations of alternative CMT process models further confirmed one of our hypotheses on the basis of previous experimental understandings. The hypothesis suggested that competition from Fe-oxide for Co(II)EDTA may account for the majority of the decrease of Co(III)EDTA effluent concentrations that resulted in the separation of total Co and Co(III)EDTA breakthrough curves. Because Co(III)EDTA is more mobile than Co(II)EDTA in the subsurface, the results of this research suggest independent quantifications of CoEDTA PMT and CMT processes if laboratory results are to be interpreted correctly and scaled up for field and predictive uses. PMID:17137677

Gwo, Jin-Ping; Mayes, Melanie A; Jardine, Philip M

2007-03-20

9

Weathering  

NSDL National Science Digital Library

This interactive Flash resource provides information regarding physical and chemical weathering at an introductory physical geology or Earth science level. It includes animations, diagrams, and supplementary information and is suitable for high school or undergraduate students.

Smoothstone; Mifflin, Houghton

10

Point process models for weather radar images  

Microsoft Academic Search

A framework for analysing weather radar (DBz) images as spatial point processes is presented. Weather radar images are modelled for the purpose of predicting their evolution in time and thereby providing a basis for short-period precipitation forecasts. An observed image sequence is modelled as a set of individual rain cells that are the outcome of a marked 2+1D spatial point

Morten Larsen; Dina KVL

1994-01-01

11

Interactive (De)Weathering of an Image using Physical Models  

E-print Network

Interactive (De)Weathering of an Image using Physical Models Srinivasa G. Narasimhan and Shree K}@cs.columbia.edu Abstract Images of scenes acquired in bad weather have poor con- trasts and colors. It is known that the degradation of image quality due to bad weather is exponential in the depths of the scene points. Therefore

Nayar, Shree K.

12

Physics 137, Section 1, Fall Semester Severe and Hazardous Weather  

E-print Network

Physics 137, Section 1, Fall Semester Severe and Hazardous Weather OBSERVATION PROJECTS During project or present one TV-type weather forecast. A list of a few possible observational projects is here of the project, information in the report might include times, dates and places of observations; weather

Hart, Gus

13

Analysis of a Sandstorm Weather Process.  

National Technical Information Service (NTIS)

The favorable synoptic situation and climate background for a sandstorm process, which occurred in the period from the 9th to the 16th of April 1988, has been studied through analyzing weather maps, meteorological elements, satellite cloud pictures and sa...

D. Yang, X. Ji

1993-01-01

14

Olivine Weathering: Abiotic Versus Biotic Processes as Possible Biosignatures  

NASA Technical Reports Server (NTRS)

A preliminary study to determine how abiotic versus biotic processes affect the weathering of olivine crystals. Perhaps the differences between these weathering processes could be used as biosignatures. Additional information is contained in the original extended abstract.

Longazo, T. G.; Wentworth, S. J.; McKay, D. S.; Southam, G.; Clemett, S. J.

2001-01-01

15

S-290 Unit 4: Basic Weather Processes  

NSDL National Science Digital Library

The âS-290 Unit 4: Basic Weather Processesâ distance learning module summarizes atmospheric structure and composition, the Sun-Earth radiation budget, weather elements used to describe the atmosphere, the greenhouse effect, and temperature lags observed both daily and seasonally. The content introduces the concepts of pressure, atmospheric heating, and temperature and provides a basis for understanding weather topics that are explored in more detail in other modules of the Intermediate Wildland Fire Behavior Course.

Comet

2008-10-27

16

Weather  

NSDL National Science Digital Library

This is a first grade weather unit. SEASONS Fall Winter Build a Snowman Spring Summer What things determine and effect the weather? Cloud Precipitation Sunshine Temperature Visibility Wind Direction Wind Force WEATHER VIDEOS Tornado Hurricane Hail Lightning FUN AND GAMES Dress the Bear for the Weather The Great Weather Race Game Weather coloring books for kids ...

Stearns, Ms.

2008-10-25

17

Weather  

NSDL National Science Digital Library

This lesson is written for fourth grade students. Students will explore weather and the effects it has on their lives. What is weather? video of what is weather Let's take a walk through the weather. Put on your hats and coats! Clouds Cloud Types Clouds - Dan's Wild Weather Page What to Wear? What to Wear? What to Drink? Weather Patterns and Climatic Regions ...

Bullough, Ms.

2010-06-24

18

Heuristics for Robust Resource Allocation of Satellite Weather Data Processing  

E-print Network

, and is trans- mitted back to the data processing system. The weather imaging data sent down by the satellite. A similar requirement is used in the satellite image processing in [19]. Currently, systems usedHeuristics for Robust Resource Allocation of Satellite Weather Data Processing on a Heterogeneous

Maciejewski, Anthony A.

19

Mechanical Weathering  

NSDL National Science Digital Library

This activity was designed to give students an opportunity to realize that all rocks weather mechanically and each specific rock type has its own particular rate of weathering. Students discover that mechanical weathering is the process of breaking down bedrock into smaller fragments by physical as opposed to chemical means and that rock weathering, although it seems to occur slowly in human terms, is an extremely significant part of the rock cycle. They will learn that weathered rock materials are called sediments and are the structural basis for soils and can also be compacted into sedimentary rock. Students will realize that rock weathering rates vary widely depending on mineral content, texture, rock type, and climate and that differential weathering (varying weathering rates for two or more rock types in physical contact with each other) has given rise to some of the world's most breathtaking scenery.

20

Weather.  

ERIC Educational Resources Information Center

This theme issue of "The Goldfinch" focuses on weather in Iowa and weather lore. The bulletin contains historical articles, fiction, activities, and maps. The table of contents lists: (1) "Wild Rosie's Map"; (2) "History Mystery"; (3) "Iowa's Weather History"; (4) "Weather Wonders"; (6) "Seasonal Jobs"; (7) "Fiction: Winter Courage"; (8) "Stayin'…

Ruth, Amy, Ed.

1996-01-01

21

Coupling processes related to the Sun-weather problem  

NASA Technical Reports Server (NTRS)

Physical mechanisms for coupling the energetics of solar activity to meteorological responses are reviewed. Although several hypotheses have been advanced, none can be said to be sufficiently complete to be applied to weather or climate prediction. Solar activity indicators potentially useful for forecasting are identified, including sunspots, solar flares, and magnetic sector boundary crossings. Additional experiments, studies, and analyses are required before Sun-weather concepts can be utilized for predicting meteorological responses.

Goldberg, R. A.; Herman, J. R.

1979-01-01

22

Weather  

NSDL National Science Digital Library

Introduction: How much do you know about weather? What kinds of weather do we have surrounding us? What is the weather like today? You may know a lot about weather already, you may not. Either way, you will learn more now as we take a look into what causes our weather and the methods we use to record and predict it. We will all become meteorologists, which are scientists who study the atmosphere and can predict weather. Put on your raincoats, and lets started! Task: You are the resident meteorologist at a local news station. It is your job to record and predict the weather each day, and then present it that night on the evening news. Not only should you be able to show the weather that we will be experiencing right ...

Hendricks, Ms.

2007-12-06

23

Weather  

NSDL National Science Digital Library

What are the different types of weather? In this project you will compare different types of weather by drawing pictures and making it into a flip book. First you will begin by learning about the different types of weather. Read about each topic. Then get together with your partner and draw a picture of each type of weather. 1. Thunder storm Thunder storm Thunder storm Kids 2. Lightning Lightning Lightning picture 3. Tornado Tornadoes Tornado Kids 4. ...

Jennie, Miss

2009-10-22

24

Influence of weather-climatic conditions on biospheric processes  

NASA Astrophysics Data System (ADS)

The significance of meteorological processes and phenomena in the biosphere functioning is revealed. The influence of various weather conditions on human health is considered; the factors and mechanisms of their action are described. The impact of meteorological processes on animals is discussed and concrete examples of such impacts are presented. The influence of meteorological processes and phenomena on plants at different stages of their life (pollination, growth, ripening, transport of seeds, damage, and death) and on some abiotic natural components is shown. It is inferred that weather-climatic conditions have a great influence on biospheric processes.

Govorushko, S. M.

2012-12-01

25

Physics 137, Section 1, Winter Semester Introduction to the Atmosphere and Weather  

E-print Network

Physics 137, Section 1, Winter Semester Introduction to the Atmosphere and Weather OBSERVATIONAL observational project or present one TV-type weather forecast. A list of a few possible observational projects; weather conditions at times of observations, data tables, charts, sketches, graphs, descriptions of what

Hart, Gus

26

Multilayer Scintillation Detector for Nuclear Physics Monitoring of Space Weather  

NASA Astrophysics Data System (ADS)

The physical characteristics of the multilayer scintillation spectrometer for identification and energy measurement of cosmic electrons, positrons and nuclei are considered in this presentation. The nuclei energy measurement range is 3-100 MeV/nucleon. This spectrometer is planning for space weather monitoring and investigation of solar-magnetospheric and geophysics effects on satellite. These characteristics were estimated by means of computer simulation. The ionization loss fluctuations, ion charge exchange during pass through detector and, especially, scintillation quenching effect (Bircs effect) were taken into account in calculations. The main results are: 1.) Ions mass identification is possible for hydrogen and helium isotopes 2.) Ions charge identification without mass identification is possible for nuclei from lithium to oxygen The preliminary estimation indicate, that including to spectrometer of thin semiconductor detector (SCD) as first layer makes possible charge identification for Z>8. This may be done by means of comparison of ion range in spectrometer with its energy loss in SCD.

Aleksandrin, Sergey; Mayorov, Andrey; Koldashov, Sergey; Batischev, Alexey; Lapushkin, Sergey; Gurov, Yury

27

Future L5 Missions for Solar Physics and Space Weather  

NASA Astrophysics Data System (ADS)

Coronal mass ejections (CMEs) and corotating interaction regions (CIR) are the sources of intense space weather in the heliosphere. Most of the current knowledge on CMEs accumulated over the past few decades has been derived from observations made from the Sun-Earth line, which is not the ideal vantage point to observe Earth-affecting CMEs (Gopalswamy et al., 2011a,b). In this paper, the advantages of remote-sensing and in-situ observations from the Sun-Earth L5 point are discussed. Locating a mission at Sun-Earth L5 has several key benefits for solar physics and space weather: (1) off the Sun-Earth line view is critical in observing Earth-arriving parts of CMEs, (2) L5 coronagraphic observations can also provide near-Sun space speed of CMEs, which is an important input to models that forecast Earth-arrival time of CMEs, (3) backside and frontside CMEs can be readily distinguished even without inner coronal imagers, (4) preceding CMEs in the path of Earth-affecting CMEs can be identified for a better estimate of the travel time, (5) CIRs reach the L5 point a few days before they arrive at Earth, and hence provide significant lead time before CIR arrival, (6) L5 observations can provide advance knowledge of CME and CIR source regions (coronal holes) rotating to Earth view, and (7) magnetograms obtained from L5 can improve the surface magnetic field distribution used as input to MHD models that predict the background solar wind. The paper also discusses L5 mission concepts that can be achieved in the near future. References Gopalswamy, N., Davila, J. M., St. Cyr, O. C., Sittler, E. C., Auchère, F., Duvall, T. L., Hoeksema, J. T., Maksimovic, M., MacDowall, R. J., Szabo, A., Collier, M. R. (2011a), Earth-Affecting Solar Causes Observatory (EASCO): A potential International Living with a Star Mission from Sun-Earth L5 JASTP 73, 658-663, DOI: 10.1016/j.jastp.2011.01.013 Gopalswamy, N., Davila, J. M., Auchère, F., Schou, J., Korendyke, C. M. Shih, A., Johnston, J. C., MacDowall, R. J., Maksimovic, M., Sittler, E., et al. (2011b), Earth-Affecting Solar Causes Observatory (EASCO): a mission at the Sun-Earth L5, Solar Physics and Space Weather Instrumentation IV. Ed. Fineschi, S. & Fennelly, J., Proceedings of the SPIE, Volume 8148, article id. 81480Z, DOI: 10.1117/12.901538

Auchere, Frederic; Gopalswamy, Nat

28

Physical process Mechanical mechanisms  

E-print Network

1 Physical process Generation · Mechanical mechanisms F = m·a · Electric/Magnetic mechanisms F = B·i·l · Fluid dynamic/Hydraulic mechanisms q, p, ij · Thermal/Optical #12;2 Source unit and source mechanisms ­ Monopoles......volume fluctuations ­ Dipoles ......pressure fluctuations

Berlin,Technische Universität

29

Process evaluation: Weatherization Residential Assistance Partnership (WRAP Program)  

SciTech Connect

The Weatherization Residential Assistance Partnership,'' or WRAP program, is a fuel-blind conservation program designed to assist Northeast Utilities' low-income customers to use energy safely and efficiently. Innovative with respect to its collaborative approach and its focus on utilizing and strengthening the existing low-income weatherization service delivery network, and WRAP program offers an interesting model to other utilities which traditionally have relied on for-profit energy service contractors and highly centralized program implementation structures. This report presents the findings of a process evaluation and WRAP customer survey conducted by the Technical Development Corporation (TDC). TDC's work is one part of a multi-part evaluation project being conducted under the management of ICF Resources, Inc.

Not Available

1990-10-01

30

Process evaluation: Weatherization Residential Assistance Partnership (WRAP Program). [Final report  

SciTech Connect

The ``Weatherization Residential Assistance Partnership,`` or WRAP program, is a fuel-blind conservation program designed to assist Northeast Utilities` low-income customers to use energy safely and efficiently. Innovative with respect to its collaborative approach and its focus on utilizing and strengthening the existing low-income weatherization service delivery network, and WRAP program offers an interesting model to other utilities which traditionally have relied on for-profit energy service contractors and highly centralized program implementation structures. This report presents the findings of a process evaluation and WRAP customer survey conducted by the Technical Development Corporation (TDC). TDC`s work is one part of a multi-part evaluation project being conducted under the management of ICF Resources, Inc.

Not Available

1990-10-01

31

Weathering processes and landforms The International Encyclopedia of Geography: People, the Earth,  

E-print Network

ForReview Only Weathering processes and landforms Journal: The International Encyclopedia Keywords: climate / landform / vegetation history, geomorphology, landforms, scale, soils Free Text, and Technology #12;ForReview Only Weathering processes and landforms Tyler J. Thompson Arizona State University

Dorn, Ron

32

Solar Physics, Space Weather, and Wide-field X-ray Telescopes  

E-print Network

Solar Physics, Space Weather, and Wide-field X-ray Telescopes CREOL & FPCE: The College of Optics of the Earth). The detrimental effects of solar storm induced "space weather" ranges from disruption of our. The National Oceanic & Atmospheric Administration (NOAA) and NASA are cooperating on a Solar X-ray Imager (SXI

Van Stryland, Eric

33

Anvil Forecast Tool in the Advanced Weather Interactive Processing System  

NASA Technical Reports Server (NTRS)

Meteorologists from the 45th Weather Squadron (45 WS) and National Weather Service Spaceflight Meteorology Group (SMG) have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violations of the Lightning Launch Commit Criteria and Space Shuttle Flight Rules. As a result, the Applied Meteorology Unit (AMU) was tasked to create a graphical overlay tool for the Meteorological Interactive Data Display System (MIDDS) that indicates the threat of thunderstorm anvil clouds, using either observed or model forecast winds as input. The tool creates a graphic depicting the potential location of thunderstorm anvils one, two, and three hours into the future. The locations are based on the average of the upper level observed or forecasted winds. The graphic includes 10 and 20 n mi standoff circles centered at the location of interest, as well as one-, two-, and three-hour arcs in the upwind direction. The arcs extend outward across a 30 sector width based on a previous AMU study that determined thunderstorm anvils move in a direction plus or minus 15 of the upper-level wind direction. The AMU was then tasked to transition the tool to the Advanced Weather Interactive Processing System (AWIPS). SMG later requested the tool be updated to provide more flexibility and quicker access to model data. This presentation describes the work performed by the AMU to transition the tool into AWIPS, as well as the subsequent improvements made to the tool.

Barrett, Joe H., III; Hood, Doris

2009-01-01

34

Activity 7SOLAR PHYSICS AND TERRESTRIAL EFFECTS 79Space Weather Prediction Center  

E-print Network

PHYSICS AND TERRESTRIAL EFFECTS 2+ 4= 81Space Weather Prediction Center 4. Drill or punch a small hole blades or small squares of aluminum cut from a soda can to make a narrow beam. 7. Set up the apparatus

35

Evidence of Space Weathering Processes Across the Surface of Vesta  

NASA Technical Reports Server (NTRS)

As NASA s Dawn spacecraft explores the surface of Vesta, it has become abundantly clear that Vesta is like no other planetary body visited to date. Dawn is collecting global data at increasingly higher spatial resolution during its one-year orbital mission. The bulk properties of Vesta have previously been linked to the HED meteorites through remote mineral characterization of its surface from Earth-based spectroscopy. A principal puzzle has been why Vesta exhibits relatively unweathered diagnostic optical features compared to other large asteroids. Is this due to the composition of this proto-planet or the space environment at Vesta? Alteration or weathering of materials in space normally develops as the products of several processes accumulate on the surface or in an evolving particulate regolith, transforming the bedrock into fragmental material with properties that may be measurably different from the original. Data from Dawn reveal that the regolith of Vesta is exceptionally diverse. Regional surface units are observed that have not been erased by weathering with time. Several morphologically-fresh craters have excavated bright, mafic-rich materials and exhibit bright ray systems. Some of the larger craters have surrounding subdued regions (often asymmetric) that are lower in albedo and relatively red-sloped in the visible while exhibiting weaker mafic signatures. Several other prominent craters have rim exposures containing very dark material and/or display a system of prominent dark rays. Most, but not all, dark areas associated with craters exhibit significantly lower spectral contrast, suggesting that either a Vesta lithology with an opaque component has been exposed locally or that the surface has been contaminated by a relatively dark impactor. Similarly, most, but not all, bright areas associated with craters exhibit enhanced mafic signatures compared to surroundings. On a regional scale, the large south polar structure and surrounding terrain exhibit relatively strong mafic absorption features, suggesting either a concentration of mafic materials or that materials exposed have been less affected by space weathering products. These combined initial observations indicate some space weathering processes are active in this part of the main asteroid belt, but are highly variable across the surface of Vesta. Such processes include: impacts from wandering asteroidal debris and local mixing at both micro- and macro-scales, irradiation by solar wind and galactic particles, production and distribution of impact breccias or melt products, and local movement of materials to gravity lows (gradual as well as sudden).

Pieters, Carle M.; Blewett, David T.; Gaffey, Michael; Mittlefehldt, David W.; CristinaDeSanctis, Maria; Reddy, Vishnu; Coradini, Angioletta; Nathues, Andreas; Denevi, Brett W.; Li, Jian-Yang; McCord, Thomas B.; Marchi, Simone; Palmer, Eric E.; Sunshine, Jessica M.; Filacchione, Gianrico; Ammannito, Eleonora; Raymond, Carol A.; Russell, Christopher T.

2011-01-01

36

Natural arsenic contamination of Holocene alluvial aquifers by linked tectonic, weathering, and microbial processes  

E-print Network

Natural arsenic contamination of Holocene alluvial aquifers by linked tectonic, weathering tectonic, geochemical, and biologic processes lead to natural arsenic contamination of groundwater are commonly found a long distance from their ultimate source of arsenic, where chemical weathering of As

Fayek, Mostafa

37

Physical weathering of marbles caused by anisotropic thermal expansion  

Microsoft Academic Search

Marbles as building stones as well as in their natural environments show complex weathering phenomena. The most important\\u000a damage scenario is based on the highly anisotropic thermal expansion coefficient ? of calcite, i.e. extreme expansion parallel and contraction normal to the crystallographic c-axis. Therefore, the rock fabric\\u000a and especially the lattice-preferred orientation (texture) of calcite and\\/or dolomite as the predominant

S. Siegesmund; K. Ullemeyer; T. Weiss; E. K. Tschegg

2000-01-01

38

Reconstructing chemical weathering, physical erosion and monsoon intensity since 25 Ma in the northern South China Sea: A review  

E-print Network

Reconstructing chemical weathering, physical erosion and monsoon intensity since 25 Ma October 2013 Accepted 7 January 2014 Available online 15 January 2014 Keywords: Monsoon Erosion Weathering Asian summer monsoon has been controversial because different proxies, many being indirect measures

Clift, Peter

39

Antarctic glaciers and rock weathering: Exploring chemical and mineralogy processes within the blue ice fields  

E-print Network

Antarctic glaciers and rock weathering: Exploring chemical and mineralogy processes within the blue, and precipitation of weathering products (e.g. magnesium carbonates and iron oxyhydroxides, or `rust'), is highly into a virtue by using weathering products to unlock the information that contain regarding the mechanisms

Guo, Zaoyang

40

Space Weathering on 4 Vesta: Processes and Products  

NASA Technical Reports Server (NTRS)

The bulk properties of Vesta have previously been linked directly to the howardite, eucrite, and diogenite (HED) meteorites through remote mineral characterization of its surface from Earth-based spectroscopy [e.g., 1]. A long-standing enigma has been why does Vesta s surface appear to have suffered so little alteration from the space environment, whereas materials exposed on the Moon and some S-type asteroids are significantly changed (grains develop rims containing nano-phase opaques [e.g. 2]). The Dawn spacecraft is well suited to address this issue and is half through its extended mapping phase of this remarkable proto-planet [3]. On a local scale Dawn sees evidence of recent exposures at craters, but distinctive surface materials blend into background at older craters. The presence of space weathering processes are thus evident at Vesta, but the character and form are controlled by the unique environment and geologic history of this small body.

Pieters, C. M.; Blewett, D. T.; Gaffey, M.; Mittlefehldt, D. W.; De Sanctis, M. C.; Reddy, V.; Nathues, A.; Denevi, B. W.; Li, J. Y.; McCord, T. B.; Marchi, S.; Palmer, E. E.; Sunshine, J. M.; Ammannito, E.; Raymond, C. A.; Russell, C. T.

2012-01-01

41

A multi-sensor physically based weather/non-weather radar echo classifier using polarimetric and environmental data in a real-time  

E-print Network

challenge in radar-derived quantitative precipitation estimation (QPE) is the separation of precipitation; Krajewski and Vignal 2001; Germann and Joss 2002) and the conversion of radar reflectivity into rain rate (iA multi-sensor physically based weather/non-weather radar echo classifier using polarimetric

Lakshmanan, Valliappa

42

Congener-specific PCB chemical and physical parameters for evaluation of environmental weathering of Aroclors  

SciTech Connect

Aqueous solubility, Henry's law constant, and vapor pressure data for PCBs were experimentally determined. Experimental data were successfully used to develop quantitative structure-property relationship models to determine factors governing selected chemical parameters. Desorption kinetics of 8PCB congeners from sediment suspensions were investigated using a gas stripping technique. Data suggest that resuspension of contaminated lake sediments can result in short term releases of up to 70 percent of the total PCBs associated with the sediment. Detailed laboratory experiments showed significant changes in the composition of PCBs can result from a series of resuspension (mixing) events. Less-chlorinated PCBs were selectively removed from the sediments while higher-chlorinated PCBs were enriched. Chemical data were used to develop a qualitative model predicting environmental weathering of Aroclors in Lake Hartwell. Model predictions were in good agreement with the laboratory results and recent field data from Lake Hartwell. Results suggest that chemical and physical processes are the major environmental weathering factors acting on PCBs in Lake Hartwell, however, some congener specific biodegradation could also be occurring.

Dunnivant, F.M.

1988-01-01

43

A Chapter In Space Weather: Physics and Effects  

E-print Network

, such as cosmic rays, solar energetic particles, radiation-belt electrons and ion species, etc. Third, different of interest, which are usually electrodynamic and plasma physical phenomena. For instance a space radiation model for the Van Allen belts should includes several physically distinct components of radiation

Vassiliadis, Dimitrios

44

Computer Animations of Physical Processes  

NSDL National Science Digital Library

This website features an extensive collection of animations of physical processes, demonstrating various concepts in waves, optics, mechanics, electricity, and thermodynamics. One distinctive characteristic of this site is that the animations are accompanied by details of the relevant physics theory pertaining to each concept, written in language appropriate for the student of introductory physics. Formulas, equations, and derivations are also provided.

2004-12-18

45

Physical Processes in Stellar Interiors  

NASA Technical Reports Server (NTRS)

The author set himself three fundamental tasks: (1) To show how modern atomic and nuclear physics can contribute to the description of processes in stellar interiors. (2) To present the fundamentals of the methods for calculating physical processes taking place at temperatures of millions of degrees. (3) To provide the required minimum of information on problems of atomic and nuclear physics to astrophysicists, and on astronomical problems to physicists. The book is divided into four parts, the Introduction, the Theory of Stationary Processes, the Applications of the Theory of Stationary Processes and the Theory of Non-Stationary Processes.

Frank-Kamenetskii, D. A.

1962-01-01

46

Physical Mechanisms of Extra Area Effects from Weather Modification.  

National Technical Information Service (NTIS)

The physical mechanisms which could have produced extra area effects downwind of the Climax I and II wintertime orographic cloud seeding experiments were investigated. The two most probable mechanisms identified, namely, artificial nuclei transport and ic...

G. J. Mulvey

1977-01-01

47

Low-Frequency Weather and the Emergence of the Climate Department of Physics, McGill University, Montreal, Quebec, Canada  

E-print Network

Low-Frequency Weather and the Emergence of the Climate S. Lovejoy Department of Physics, Mc, Paris, France Meteo France, Paris, France We survey atmospheric variability from weather scales up are rapidly quenched, leading to a scaling "low-frequency weather" regime extending out to Le::::: 10

Lovejoy, Shaun

48

Low-Frequency Weather and the Emergence of the Climate Department of Physics, McGill University, Montreal, Quebec, Canada  

E-print Network

Low-Frequency Weather and the Emergence of the Climate S. Lovejoy Department of Physics, Mc, Paris, France Météo France, Paris, France We survey atmospheric variability from weather scales up quenched, leading to a scaling "low-frequency weather" regime extending out to c 10­100 years

Lovejoy, Shaun

49

Spring Break-Weathering Homework  

NSDL National Science Digital Library

Students are asked to photograph something that shows either physical or chemical weathering. They must be in the photograph for purposes of scale. They must then write up their description of the weathering feature and explain the actual weathering processes. This assignment can also be expanded to include mass wasting and mass wasting prevention.

Farthing, Dori

50

Weather Modification: Finding Common Ground  

Microsoft Academic Search

Research and operational approaches to weather modification expressed in the National Research Council's 2003 report on ``Critical Issues in Weather Modification Research'' and in the Weather Modification Association's response to that report form the basis for this discussion. There is agreement that advances in the past few decades over a broad front of understanding physical processes and in technology have

Michael Garstang; Roelof Bruintjes; Robert Serafin; Harold Orville; Bruce Boe; William Cotton; Joseph Warburton

2005-01-01

51

Activity 2SOLAR PHYSICS AND TERRESTRIAL EFFECTS 53Space Weather Prediction Center  

E-print Network

the solar interior to the surface is based on probability and statistics. Even though the exercise describedActivity 2SOLAR PHYSICS AND TERRESTRIAL EFFECTS 2+ 4= 53Space Weather Prediction Center Activity 2 Energy Transport in the Sun Purpose This is a 2-D demonstration of how a photon--a small bundle of light

52

Relationship between objective measures of physical activity and weather: a longitudinal study  

Microsoft Academic Search

: BACKGROUND: The weather may be a barrier to physical activity but objective assessment of this hypothesis is lacking. Therefore we evaluated the effect of temperature, rain or snow, and wind speed on the daily physical activity of adults. METHODS: This report contains data from 25 males (BMI (mean ± SD): 28.7 ± 3.83 kg\\/m2) and 177 females (BMI: 29.2

Catherine B Chan; Daniel AJ Ryan; Catrine Tudor-Locke

2006-01-01

53

Using MSG-SEVIRI Cloud Physical Properties and Weather Radar Observations for the Detection of Cb/TCu Clouds  

E-print Network

Using MSG-SEVIRI Cloud Physical Properties and Weather Radar Observations for the Detection of Cb (SEVIRI) on board Meteosat Second Generation (MSG) satellites and weather radar reflectivity factors/TCu clouds for the collection of pixels that pass the CCM. In this model, MSG-SEVIRI cloud physical

Schmeits, Maurice

54

A reactive transport perspective on the links between physical erosion rates, fluid flow and chemical weathering rates  

NASA Astrophysics Data System (ADS)

Chemical weathering rates are theoretically governed by the balance between the time that fluid spends in contact with the rock, or the fluid transit time, and the time required to reach chemical equilibrium. Physical erosion is expected to be the first order control on the chemical equilibrium timescale because the supply of fresh mineral increases the rate of approach to chemical equilibrium. In weathering environments where fluid transit times are long relative to the equilibrium timescale, chemical weathering rates should increase with increasing water flux (or runoff) because the concentration of weathering products is always fixed by chemical equilibrium. By extension, short fluid transit times and/or long chemical equilibrium times result in lower concentrations and a plateau in chemical weathering rates with increasing runoff. To assess the relationship between physical erosion and equilibrium time scales, we analyzed soil water, stream and gas compositions across multiple seasons along three hillslope transects in the Feather River Basin, California, with varying erosion rates but identical lithology, vegetation and climate. We use the depth gradients in solute profiles and mineral saturation states to assess the equilibrium length scales (the depth over which fluids reach chemical equilibrium), which can then be compared to the equilibrium and transit time scales based on water fluxes measured by chloride mass balance. Calculated equilibrium length scales increase from an average of 30-40 cm at high erosion rate transect, to 80 to 100 cm at lower erosion rates. At high erosion rates, the fluids reach chemical equilibrium in the soil zone, and there is little driving force for chemical weathering in the saprolite. At lower erosion rates, the equilibrium length scale extends into the saprolite, while minimal weathering occurs in the soil zone because of passivation of mineral surfaces by secondary minerals. Liquid saturation also increases with decreasing erosion rate—this may favor biological activity that further enhances weathering in the saprolite resulting in the high CO2 levels (ca. 2 to 5%) in the saprolite at low erosion rates. Across all three transects, chemical weathering rates are limited by the rate of fluid flow and not the rate of mineral supply: average infiltration rates are highest at the higher erosion rate transect, resulting in higher rates of chemical denudation. Thermodynamic limitation of chemical weathering rates is consistent with the streamwater concentrations, which show minimal variation with discharge (i.e. chemostatic behavior). A substantial reservoir of immobile solute, which is observed here to increase with increasing erosion rate, appears to play an important role in facilitating thermodynamic limitation. Collectively, these results support the theoretical model for solute production described above, and emphasize the importance of considering the thermodynamic limitations on chemical weathering rates that are set by the physical process of erosion and fluid flow.

Maher, K.; Kouba, C. M.; Rosen, V. B.; Weinman, B. A.; Yoo, K.; Mudd, S. M.

2012-12-01

55

Weathering Animation  

NSDL National Science Digital Library

Weathering is the term that describes all the processes that break down rocks in the environment near the Earth's surface. This module will help you to understand two weathering processes: mechanical and chemical.

2002-01-01

56

Long-term rates of chemical weathering and physical erosion from cosmogenic nuclides and geochemical mass balance  

Microsoft Academic Search

Quantifying long-term rates of chemical weathering and physical erosion is important for understanding the long-term evolution of soils, landscapes, and Earth's climate. Here we describe how long-term chemical weathering rates can be measured for actively eroding landscapes using cosmogenic nuclides together with a geochemical mass balance of weathered soil and parent rock. We tested this approach in the Rio Icacos

Clifford S. Riebe; James W. Kirchner; Robert C. Finkel

2003-01-01

57

Gombosi Receives 2013 Space Weather and Nonlinear Waves and Processes Prize: Response  

NASA Astrophysics Data System (ADS)

It is a great honor to be the recipient of AGU's inaugural Space Weather and Nonlinear Waves and Processes Prize. I am truly humbled by this recognition because there are many other highly deserving colleagues in our research field.

Gombosi, Tamas

2014-08-01

58

Chemical weathering and soil production 1 Copyright 2006 John Wiley & Sons, Ltd. Earth Surf. Process. Landforms (in press)  

E-print Network

Chemical weathering and soil production 1 Copyright © 2006 John Wiley & Sons, Ltd. Earth Surf.1443 Introduction Hillslope forms evolve over time as a result of total weathering, the sum of physical). Total weathering is equivalent to erosion, the net removal of soil and other material from the hillslope

Heimsath, Arjun M.

59

Processing of Indian Doppler Weather Radar data for mesoscale applications  

NASA Astrophysics Data System (ADS)

This paper demonstrates the usefulness of Indian Doppler Weather Radar (DWR) data for nowcasting applications, and assimilation into a mesoscale Numerical Weather Prediction (NWP) model. Warning Decision Support System Integrated Information (WDSS-II) developed by National Severe Storm Laboratory (NSSL) and Advanced Regional Prediction System (ARPS) developed at the Centre for Analysis and Prediction, University of Oklahoma are used for this purpose. The study reveals that the WDSS-II software is capable of detecting and removing anomalous propagation echoes from the Indian DWR data. The software can be used to track storm cells and mesocyclones through successive scans. Radar reflectivity mosaics are created for a land-falling tropical cyclone—Khaimuk of 14 November 2008 over the Bay of Bengal using observations from three DWR stations, namely, Visakhapatnam, Machilipatnam and Chennai. Assimilation of the quality-controlled radar data (DWR, Chennai) of the WDSS-II software in a very high-resolution NWP model (ARPS) has a positive impact for improving mesoscale prediction. This has been demonstrated for a land-falling tropical cyclone Nisha of 27 November 2008 of Tamil Nadu coast. This paper also discusses the optimum scan strategy and networking considerations. This work illustrates an important step of transforming research to operation.

Roy Bhowmik, S. K.; Sen Roy, Soma; Srivastava, Kuldeep; Mukhopadhay, B.; Thampi, S. B.; Reddy, Y. K.; Singh, Hari; Venkateswarlu, S.; Adhikary, Sourav

2011-03-01

60

Weathering and Erosion  

NSDL National Science Digital Library

This Classroom Connectors lesson plan discusses weather conditions and their contribution to weathering and erosion. Students learn to explain the process of physical and chemical weathering. They also learn to compare and contrast erosion resulting from wind, ice and water. The site provides goals, objectives, an outline, time required, materials, activities, and closure ideas for the lesson. The Classroom Connectors address content with an activity approach while incorporating themes necessary to raise the activity to a higher cognition level. The major motivation is to employ instructional strategies that bring the students physically and mentally into touch with the science they are studying.

61

CHEMICAL WEATHERING AND SOLUTION CHEMISTRY IN ACID FOREST SOILS: DIFFERENTIAL INFLUENCE OF SOIL TYPE, BIOTIC PROCESSES, AND H+ DEPOSITION  

EPA Science Inventory

In the investigation, weathering rates were calculated for three eastern North American forest soils using five separate estimation techniques. In addition, leaching experiments were performed to examine the influence of selected environmental variables on the weathering process....

62

Conversion of bedrock to soil and feedback processes between the surface and the weathering front in a deeply weathered regolith, Central Sri Lankan Highlands  

NASA Astrophysics Data System (ADS)

In the Sri Lankan highlands denudation rates and chemical weathering rates represent the low-end-member in global weathering rates [1, 2]. Here we explore the causes for these low rates by a detailed soil-mineralogical study of a highly weathered deep saprolite profile developed from charnockite bedrock. Spheroidal weathering of the bedrock characterized the weathering front where rounded corestones are produced at the rock-saprolite interface. The first mineral attacked by weathering was found to be pyroxene but plagioclase is the first mineral depleted to near-completion at the corestone-saprolite-boundary. Weathering of pyroxene is initiated by in situ iron oxidation, leading to an increase of porosity due to micro-cracking [3]. The accrued micro cracks allow for fluid transport and the dissolution of biotite and plagioclase. The strong plagioclase weathering leads to formation of high secondary porosity over a small distance and the final disaggregation of bedrock to saprolite. Sequential extraction showed that the first secondary phases are amorphous oxides from which secondary minerals (gibbsite, kaolinite, goethite and minor amounts of smectites) precipitate. Modeling of the strain formation due to increasing volume during iron oxidation in pyroxene and biotite showed that spheroidal weathering can be explained with this process only if the formation of secondary porosity, due to a negative volume budget during primary mineral weathering to secondary phases, occurs. As oxidation is the first occurring reaction, O2 is a rate limiting factor for chemical weathering in this setting. Hence the supply of oxygen and the consumption at depth connects processes at the weathering front with those at the surface as a feedback mechanism. Advective and diffusive transport modeling shows that the feedback will be much more pronounced with dominating diffusive transport. Due to the low porosity of the bedrock the O2 transport in the pristine bedrock occurs via diffusion. The slow weathering rate is, beside tectonic quiescence, related to this feedback and to lithological factors such as low porosity and the amount of Fe-bearing primary minerals. 1. Hewawasam, T., et al., Slow advance of the weathering front during deep, supply-limited saprolite formation in the tropical Highlands of Sri Lanka. Geochimica et Cosmochimica Acta, 2013. 118: p. 202-230. 2. von Blanckenburg, F., T. Hewawasam, and P. Kubik, Cosmogenic nuclide evidence for low weathering and denudation in the wet tropical Highlands of Sri Lanka. J. Geoph. Res., 2004. 109: p. doi10.1029/2003JF000049. 3. Buss, H.L., et al., Weathering of the Rio Blanco quartz diorite, Luquillo Mountains, Puerto Rico: Coupling oxidation, dissolution, and fracturing. Geochimica et Cosmochimica Acta, 2008. 72(18): p. 4488-4507.

Behrens, Ricarda; Bouchez, Julien; Schuessler, Jan A.; Dultz, Stefan; Hewawasam, Tilak; von Blanckenburg, Friedhelm

2014-05-01

63

Development of alteration rinds by oxidative weathering processes in Beacon Valley, Antarctica, and implications for Mars  

NASA Astrophysics Data System (ADS)

Alteration of fresh rock surfaces proceeds very rapidly in most terrestrial environments so that initial stages of modification of newly exposed surfaces are quickly masked by subsequent aqueous weathering processes. The hyper-arid and hypo-thermal environment of Beacon Valley, Antarctica, is limited in terms of available liquid water and energy available for alteration, which severely slows weathering processes so that the initial stages of alteration can be studied in detail. We report on the nature of initial chemical alteration of the Ferrar Dolerite in Beacon Valley, Antarctica, using a multiplicity of approaches to characterize the process. We suggest that initial chemical alteration is primarily driven by cation migration in response to the oxidizing environment. Morphological studies of altered rock surfaces reveal evidence of small-scale leaching and dissolution patterns as well as physical erosion due to surface weakening. Within the alteration front, mineral structures are largely preserved and alteration is only indicated by discrete zones of discoloration. Mineralogical investigations expose the complexity of the alteration process; visible/near-infrared reflectance and mid-infrared emission spectroscopy reveal significant variations in mineralogical contributions that are consistent with the introduction of oxide and amorphous phases at the surfaces of the rocks, while X-ray diffraction analyses reveal no definitive changes in mineralogy or material properties. Chemical analyses reveal large-scale trends that are consistent with cation migration and leaching, while small-scale electron microprobe analyses indicate that chemical variations associated with magmatic processes are still largely preserved within the alteration rind. This work confirms the incomplete and immature chemical alteration processes at work in the McMurdo Dry Valleys. Liquid water is not a significant contributor to the alteration process at this early stage of rind development, but assists in the removal of alteration products and their local accumulation in the surrounding sediments. These results also suggest that the McMurdo Dry Valleys (and Beacon Valley, in particular) are relevant terrestrial analogs to hyper-arid and hypo-thermal alteration processes that may be dominant on the martian surface.

Salvatore, M. R.; Mustard, J. F.; Head, J. W.; Cooper, R. F.; Marchant, D. R.; Wyatt, M. B.

2013-08-01

64

doi:10.1016/S0016-7037(03)00382-X Long-term rates of chemical weathering and physical erosion from cosmogenic nuclides  

E-print Network

doi:10.1016/S0016-7037(03)00382-X Long-term rates of chemical weathering and physical erosion from weathering and physical erosion is important for under- standing the long-term evolution of soils, landscapes, and Earth's climate. Here we describe how long-term chemical weathering rates can be measured for actively

Kirchner, James W.

65

Chemical weathering processes in the Great Artesian Basin: Evidence from lithium and silicon isotopes  

NASA Astrophysics Data System (ADS)

Variations in lithium and silicon isotope ratios in groundwaters of the Great Artesian Basin in Australia, and the causes of these variations, have been explored. The chemistries of Li and Si in groundwater are influenced by the dissolution of primary phases, the formation of secondary minerals, and the reaction of solid phases with dissolved constituents, while isotopic variations are generated by uptake into clays, which preferentially incorporate the light isotopes. The lithium isotopic composition (expressed as ? 7Li) of the groundwaters ranges from +9 to +16‰ , and clearly reflects changes in aquifer conditions. Reaction-transport modelling indicates that changes in Li concentrations are principally controlled by the ratio of the weathering rate of primary minerals to the precipitation rate of secondary minerals, whereas ? 7Li is affected by the extent of isotope fractionation during secondary mineral formation (which is dependent on mineralogy). The patterns of groundwater Si concentrations and ? 30Si values versus flow distance suggest that Si is at steady state in the aquifer. The ? 30Si value of most of the groundwater samples is close to -1‰ , which is significantly lower than the ? 30Si value of the reservoir rocks (?0‰ ). Since precipitation of clays preferentially removes the light Si isotopes from solution, the most plausible explanation for these low groundwater ? 30Si values is addition of Si by dissolution of isotopically light secondary minerals. These data, together with model calculations, show that Li isotopes are extremely sensitive to changes in the chemical and physical conditions in the aquifer, whereas Si is not. Importantly, the model suggests that even in large aquifers with long fluid residence times, where steady-state would be expected to be reached, the concentrations and isotopic fractionation of trace elements are not controlled by Li adsorption. The model developed here provides a basis for using Li isotopes measured in groundwaters and surface waters to constrain weathering processes.

Pogge von Strandmann, Philip A. E.; Porcelli, Don; James, Rachael H.; van Calsteren, Peter; Schaefer, Bruce; Cartwright, Ian; Reynolds, Ben C.; Burton, Kevin W.

2014-11-01

66

Two-dimensional gas chromatography/mass spectrometry, physical property modeling and automated production of component maps to assess the weathering of pollutants.  

PubMed

Local conditions influence how pollutants will weather in subsurface environments and sediment, and many of the processes that comprise environmental weathering are dependent upon these substances' physical and chemical properties. For example, the effects of dissolution, evaporation, and organic phase partitioning can be related to the aqueous solubility (SW), vapor pressure (VP), and octanol-water partition coefficient (KOW), respectively. This study outlines a novel approach for estimating these physical properties from comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC/MS) retention index-based polyparameter linear free energy relationships (LFERs). Key to robust correlation between GC measurements and physical properties is the accurate and precise generation of retention indices. Our model, which employs isovolatility curves to calculate retention indices, provides improved retention measurement accuracy for families of homologous compounds and leads to better estimates of their physical properties. Results indicate that the physical property estimates produced from this approach have the same error on a logarithmic-linear scale as previous researchers' log-log estimates, yielding a markedly improved model. The model was embedded into a new software program, allowing for automated determination of these properties from a single GC×GC analysis with minimal model training and parameter input. This process produces component maps that can be used to discern the mechanism and progression of how a particular site weathers due to dissolution, organic phase partitioning, and evaporation into the surrounding environment. PMID:25223613

Antle, Patrick M; Zeigler, Christian D; Livitz, Dimitri G; Robbat, Albert

2014-10-17

67

Space Weather data processing and Science Gateway for the Van Allen Probes  

NASA Astrophysics Data System (ADS)

A near real-time data processing pipeline for the Space Weather broadcast data from the Van Allen Probes is presented. The Van Allen Probes broadcasts a sub-set of the science data in real-time when not downlinking the principal science data. This broadcast is received by several ground stations and relayed to APL in near real time to be ingested into the space weather processing pipeline. This pipeline processes the available level zero space weather data into higher level science data products. These products are made available to the public via the Van Allen Probes Science Gateway website (http://athena.jhuapl.edu). The website acts as pivotal point though which all other instrument SOC's can be accessed. Several other data products (e.g KP/DST indices) and tools (e.g orbit calculator) are made also available to the general public.

Romeo, G.; Barnes, R. J.; Weiss, M.; Fox, N. J.; Mauk, B.; Potter, M.; Kessel, R.

2013-12-01

68

AN URBAN WEATHER GENERATOR COUPLING BUILDING SIMULATIONS WITH A PHYSICALLY BASED URBAN MODEL  

Microsoft Academic Search

Building simulation programs predict the thermal performance of buildings under certain weather conditions. Weather information is usually taken from an available weather data file obtained from the closest meteorological station. However, the differences between the local urban climate and the conditions at the closest meteorological station can lead to inaccurate building simulation results. This paper presents an Urban Weather Generator

Bruno Bueno Unzeta; Leslie K. Norford; Rex Britter

69

Working Process Development For Weathering Degree Mapping Of Stone Monument Using Reflectance Spectroscopy  

NASA Astrophysics Data System (ADS)

Most stone monuments have been weathered on the field with exposure of rain and wind during hundreds or thousands years. Reflectance spectroscopy can be applied to assess weathering degree of those stone monuments composed of granite which is the most general material of stone monument in Korea. Weathering degree was analyzed by using reflected and transmitted electromagnetic energy based on the theory of reflectance spectroscopy on the surface of rock to identify rock forming minerals using their diagnostic spectral absorption features. This method could be used as an improved nondestructive assessment method compared with conventional subjective and qualitative assessment methods. We tested feasibility of this technique for actual granite stone monuments. Granite is generally composed of quartz, feldspars and micas. Feldspars are changed to clay minerals such as kaolinite and illite after weathering process. Biotite of mica produce iron oxides which induce color changes on surface of rocks. The experiments were conducted using field spectrometer FieldSpec®3 of ASD Inc. and the range of measurement was form 350µm to 2500µm wavelength. Spectral reflectance of weathering products at each measuring point was processed by removing delineated convex hull from raw reflectance curves to exclude background effects and to extract quantitative absorption depths which indicate relative distribution degree of weathering products. We produced deterioration map on the surface of the monument by interpolating absorption depth values of each point with consideration of spatial distribution of measurements. For facilitation of practical uses a chain of working process of this method was designed using whole experimental processes.

Hyun, C.; Park, H.

2008-12-01

70

RBSP Space Weather data  

NASA Astrophysics Data System (ADS)

On August 23, 2012, NASA will launch two identical probes into the radiation belts to provide unprecedented insight into the physical processes and dynamics of near-Earth space. The RBSP mission in addition to the scientific data return, provides a 1Kbps real-time space weather broadcast data in support of real time space weather modeling, forecast and prediction efforts. Networks of ground stations have been identified to downlink the space weather data. The RBSP instrument suites have selected space weather data to be broadcast from their collected space data on board the spacecraft, a subset from measurements based on information normally available to the instrument. The data subset includes particle fluxes at a variety of energies, and magnetic and electric field data. This selected space weather data is broadcast at all times through the primary spacecraft science downlink antennas when an observatory is not in a primary mission-related ground contact. The collected data will resolve important scientific issues and help researchers develop and improve various models for the radiation belts that can be used by forecasters to predict space weather phenomena and alert astronauts and spacecraft operators to potential hazards. The near real-time data from RBSP will be available to monitor and analyze current environmental conditions, forecast natural environmental changes and support anomaly resolution. The space weather data will be available on the RBSP Science Gateway at http://athena.jhuapl.edu/ and will provide access to the space weather data received from the RBSP real-time space weather broadcast. The near real-time data will be calibrated and displayed on the web as soon as possible. The CCMC will ingest the RBSP space weather data into real-time models. The raw space weather data will be permanently archived at APL. This presentation will provide a first look at RBSP space weather data products.

Weiss, M.; Fox, N. J.; Mauk, B. H.; Barnes, R. J.; Potter, M.; Romeo, G.; Smith, D.

2012-12-01

71

Real-time Storm Detection and Weather Forecast Activation through Data Mining and Events Processing  

E-print Network

Real-time Storm Detection and Weather Forecast Activation through Data Mining and Events Processing in real time over large volumes of observational data. 1. Introduction Information technology research has of use cases that involve the sensing and recognition of severe storms, and associated complex parallel

Plale, Beth

72

Pb isotope systematics in volcanic river system: Constraints about weathering processes  

E-print Network

Pb isotope systematics in volcanic river system: Constraints about weathering processes Ph. NEGREL.negrel@brgm.fr, r.millot@brgm.fr, e.petelet@brgm.fr, We present a series of lead isotopes in soils and sediments, as witnessed by lead isotopic variations in conjunction with Rb/La ratios and lead contents. Using Pb isotope

Boyer, Edmond

73

Major ion chemistry and weathering processes in the Midyan Basin, northwestern Saudi Arabia.  

PubMed

Chemical characteristics of 72 groundwater samples collected from Midyan Basin have been studied to evaluate major ion chemistry together with the geochemical and weathering processes controlling the water composition. Water chemistry of the study area is mainly dominated by Na, Ca, SO4, and Cl. The molar ratios of (Ca?+?Mg)/total cations, (Na?+?K)/total cations, (Ca?+?Mg)/(Na?+?K), (Ca?+?Mg)/(HCO3?+?SO4), (Ca?+?Mg)/HCO3, and Na/Cl reveal that water chemistry of the Midyan Basin is controlled by evaporite dissolution (gypsum and/or anhydrite, and halite), silicate weathering, and minor contribution of carbonate weathering. The studied groundwater samples are largely undersaturated with respect to dolomite, gypsum, and anhydrite. These waters are capable of dissolving more of these minerals under suitable physicochemical conditions. PMID:23609922

Ghrefat, Habes A; Batayneh, Awni; Zaman, Haider; Zumlot, Taisser; Elawadi, Eslam; Nazzal, Yousef

2013-10-01

74

Physical and chemical weathering in modern and Permian proximal fluvial systems  

NASA Astrophysics Data System (ADS)

Chapter 1 Inferring paleoclimate from ancient fluvial strata can be challenging, and conflicting interpretations for a given system are common in the literature. This research uses a combination of physical and chemical weathering signals in an attempt to better define the paleoclimatic interpretations for the proximal Cutler Formation near Gateway, Colorado (Chapter 3) and the Post Oak Conglomerate in the Wichita Mountains, Oklahoma (Chapter 4), both Permian units. Chapter 4 includes a comparison of weathering signals from modern sediments in the Wichita Mountains. A methodology for pretreatment techniques used for grain-size analysis was evaluated during the course of the research and is the topic of Chapter 2. This dissertation is organized as three stand-alone manuscripts and a brief summary of each is presented below. Chapter 2 Pretreatment drying of mud-sized sediment (<63 im) resulted in clayrich (>39%) samples exhibiting more sensitivity to drying techniques than clay-poor (<39%) samples. This demonstrates an influence of the drying technique on the granulometric results. Employing freeze drying for sample drying yielded the most consistent results. However, for samples with <39% clay-sized material, all drying techniques are equally effective, and no apparent need exists for the extra effort (and expense) that accompanies freeze drying. Chapter 3 Scanning Electron Microscopy is a useful tool in the study of quartz grain microtextures. Microtextures on quartz grains from the proximal Cutler Formation near Gateway, CO were documented for the presence/absence of 18 distinct microtextures. Averaging of presence/absence data for the samples provided a means to use more quantitative techniques than previously employed for SEM microtextural analysis. These continuous quantitative variables were utilized for non-metric multidimensional scaling, a purely quantitative technique that does not rely on initial assumptions of what environments produce specific microtextures. Chapter 4 The Post Oak Conglomerate was deposited in a climate much wetter than the modern climate of the Wichita Mountains today. Significant amounts of clay, high percentages of Al2O3 in the mud fraction, spheroidal weathering, thick weathering rinds, and hyperconcentrated flood flow deposits are prominent in the Post Oak conglomerate and lacking in the modern Blue Beaver Creek sediment. When compared to other modern climates, the Post Oak Conglomerate fits best with a tropical climate. The climate of the region for the Early Permian is commonly interpreted to be arid. However; these results suggest a brief time period of wet conditions in the Wichita Mountains prior to the onset of the aridity documented in younger Permian units of the area.

Keiser, Leslie Jo

75

Activity Level, Activity Enjoyment, and Weather as Mediators of Physical Health Risks in Seasonal and Nonseasonal Depression  

Microsoft Academic Search

Research suggests that depression has negative consequences on physical health. One of the mechanisms driving this link may\\u000a be the decrease in physical activity characteristic of individuals before and during a depressive episode. However, the factors\\u000a that influence changes in physical activity across the seasons remain unclear. For instance, weather has been proposed to\\u000a play an important role in the

Sandra T. SigmonJanell; Janell G. Schartel; Nina E. Boulard; Geoffrey L. Thorpe

2010-01-01

76

The effect of weather on walking behavior among older adults4 Accepted and forthcoming, Journal of Aging and Physical Activity8  

E-print Network

1 2 3 The effect of weather on walking behavior among older adults4 5 6 7 Accepted and forthcoming with walking behavior for either gender.14 15 16 #12;Introduction1 In this paper we examine how weather Mouton, 2003) and the role of weather on physical activity (hereafter PA) (Eisenberg & Okeke,7 2009

Shaw, W. Douglass

77

Physical Fitness and the Stress Process  

ERIC Educational Resources Information Center

In the current paper we focus on the role of physical fitness in the life stress process for both psychological and physical well-being. The major research question posed in the current study is: Does physical fitness deter distress in a model containing the major components of the life stress process? That is, do individuals who exercise show…

Ensel, Walter M.; Lin, Nan

2004-01-01

78

Mismatched Physical and Chemical Weathering of Rocks on Mars: Clues to Past Climate  

NASA Astrophysics Data System (ADS)

Here we quantify the degree of weathering experienced by the Adirondack-class basalts at the MER Spirit site by performing comparative analyses on the strength and chemistry of a series of progressively weathered Columbia River Basalt samples.

Thomson, B. J.; Hurowitz, J. A.; Baker, L. L.; Bridges, N. T.; Lennon, A.; Paulson, G.; Zacny, K.

2014-07-01

79

Vadose Zone Processes and Chemical Transport Effects of Spent Mushroom Substrate Weathering on the Chemistry of Underlying Soils  

E-print Network

Vadose Zone Processes and Chemical Transport Effects of Spent Mushroom Substrate Weathering on the Chemistry of Underlying Soils Mingxin Guo, Jon Chorover,* and Richard H. Fox ABSTRACT mushroom production mushroom substrate (SMS) before its reuse. During the weathering process, leachate containing high

Chorover, Jon

80

Rock-weathering rates as functions of time  

USGS Publications Warehouse

The scarcity of documented numerical relations between rock weathering and time has led to a common assumption that rates of weathering are linear. This assumption has been strengthened by studies that have calculated long-term average rates. However, little theoretical or empirical evidence exists to support linear rates for most chemical-weathering processes, with the exception of congruent dissolution processes. The few previous studies of rock-weathering rates that contain quantitative documentation of the relation between chemical weathering and time suggest that the rates of most weathering processes decrease with time. Recent studies of weathering rinds on basaltic and andesitic stones in glacial deposits in the western United States also clearly demonstrate that rock-weathering processes slow with time. Some weathering processes appear to conform to exponential functions of time, such as the square-root time function for hydration of volcanic glass, which conforms to the theoretical predictions of diffusion kinetics. However, weathering of mineralogically heterogeneous rocks involves complex physical and chemical processes that generally can be expressed only empirically, commonly by way of logarithmic time functions. Incongruent dissolution and other weathering processes produce residues, which are commonly used as measures of weathering. These residues appear to slow movement of water to unaltered material and impede chemical transport away from it. If weathering residues impede weathering processes then rates of weathering and rates of residue production are inversely proportional to some function of the residue thickness. This results in simple mathematical analogs for weathering that imply nonlinear time functions. The rate of weathering becomes constant only when an equilibrium thickness of the residue is reached. Because weathering residues are relatively stable chemically, and because physical removal of residues below the ground surface is slight, many weathering features require considerable time to reach constant rates of change. For weathering rinds on volcanic stones in the western United States, this time is at least 0.5 my. ?? 1981.

Colman, S. M.

1981-01-01

81

Spectrometric investigation of the weathering process affecting historical glasses of León Cathedral, Spain  

NASA Astrophysics Data System (ADS)

Atmospheric pollution plays important roles in the weathering of the historical buildings and glass windows. Samples of white powdered weathering products, recovered during restoration of the stained-glass windows of León Cathedral in Spain, were characterised using a combination of scanning electron microscopy (SEM) with energy dispersive-X ray spectrometry (ED-XRS), Fourier transform-infrared (FT-IR) spectroscopy and Raman spectrometry. The presence of sulphates, and to a lesser extent carbonates, in the white powdered product is clear indication of the participation of atmospheric acidifying gases, particularly SOx, in the weathering process. It is interesting to note that there was no indication of the participation of NOx gases. There was, however, evidence that the putty and mortar used to seal/join the glasses were major sources of the weathering products. In this way, this study suggests sealants more resistant to oxidation, such as silicone- and zirconia-based materials, should be considered for repairing glass windows in historic buildings to avoid exacerbating degradation.

Castro, M. A.; Pereira, F. J.; Aller, A. J.; Littlejohn, D.

2014-12-01

82

Automatic processing, quality assurance and serving of real-time weather data  

NASA Astrophysics Data System (ADS)

Recent advances in technology have produced a significant increase in the availability of free sensor data over the Internet. With affordable weather monitoring stations now available to individual meteorology enthusiasts, a reservoir of real time data such as temperature, rainfall and wind speed can now be obtained for most of the world. Despite the abundance of available data, the production of usable information about the weather in individual local neighbourhoods requires complex processing that poses several challenges. This paper discusses a collection of technologies and applications that harvest, refine and process this data, culminating in information that has been tailored toward the user. In this instance, this allows a user to make direct queries about the weather at any location, even when this is not directly instrumented, using interpolation methods provided by the INTAMAP project. A simplified example illustrates how the INTAMAP web processing service can be employed as part of a quality control procedure to estimate the bias and residual variance of user contributed temperature observations, using a reference standard based on temperature observations with carefully controlled quality. We also consider how the uncertainty introduced by the interpolation can be communicated to the user of the system, using UncertML, a developing standard for uncertainty representation.

Williams, Matthew; Cornford, Dan; Bastin, Lucy; Jones, Richard; Parker, Stephen

2011-03-01

83

The physics of natural precipitation processes  

Microsoft Academic Search

A critical survey is given of the physical processes responsible for the release of precipitation such as drizzle, rain, snow, and hail in middle and low latitudes. By suitable analyses of long series of airplane observations of characteristic states in layer and shower clouds indications are derived for the type of the efficient physical processes. Investigations carried out at the

B. J. Mason

1955-01-01

84

External Resource: Mechanical Weathering  

NSDL National Science Digital Library

A student activity with teacher's sheet, to give the students an opportunity to realize that all rocks weather mechanically and each specific rock type has its own particular rate of weathering. Mechanical weathering is the process of breaking down bedroc

1900-01-01

85

Mathematical and physical modelling of materials processing  

NASA Technical Reports Server (NTRS)

Mathematical and physical modeling of turbulence phenomena in metals processing, electromagnetically driven flows in materials processing, gas-solid reactions, rapid solidification processes, the electroslag casting process, the role of cathodic depolarizers in the corrosion of aluminum in sea water, and predicting viscoelastic flows are described.

1982-01-01

86

Lithium and carbon isotopes in river catchment: combined tracers to constrain chemical weathering processes  

NASA Astrophysics Data System (ADS)

Water-rock interactions produced in river catchment are accompanied by fractionation or changes in stable isotopes such as H, Li, C and O during chemical weathering processes. Li is a fluid-mobile element that tends to preferentially partition into the fluid phase during water-rock interaction. The relative mass difference between the two isotopes is considerable, generating large mass dependent fractionation during chemical weathering processes. The CO2 dissolves into the water providing the main acid that attack the rock during chemical weathering. Carbon stable isotopes and concentration of Dissolved Inorganic Carbon (DIC) in the river catchment can be used to determine the origin and consumption rates of CO2. In the present work, stable isotopes were analyzed in Allier River, one of the major river basins of France. The lithology is dominated by granite rocks within current upstream, while it is mainly basaltic and Oligocene sediments in the downstream with hydrothermal manifestations. We propose a new isotopic approach by combining ?7Li and ?13CDIC analyses in river catchment waters. A first method has been applied to volcanic tropical environments with Li concentrations correlated to ?13CDIC (Rad et al., 2011). Here, we have completed this approach by lithium isotopes. Water samples were collected during several field trips. Our results show a large variation in Li isotopes and C isotopes within the catchment from 3.3 ‰ to 30.3 ‰ and from -17.9‰ to -3.5‰, respectively. Chemical weathering rates linearly increase from upstream to downstream over 400km distance, whereas Li isotope signatures decrease and global C signature increases. This is due to low water-rock interaction dominated in upstream, whereas the downstream is punctually impacted by hydrothermalism. From Li and C isotopes, our results show 4 groups reflecting different chemical weathering processes: the first group with high fractionation of Li and C, for Li, the heavy lithium partitioned into surface waters, leaving lighter lithium behind in the weathered products, the signature of C is mainly due to organic matter or partially due to biochemical interaction with assimilation of CO2 by microorganism. The second group involves atmospheric equilibrium with CO2 degassing with organic origin or "cold" CO2 degassing with important fraction of Li. The third group present high fractionation of C, reflecting presence of superficial C with organic origin, with low fractionation of Li underling the hydrothermalism impact. Finally a fourth group with low fractionation mainly due to high temperature water-rock interaction. Therefore, the combination of the two tracers, Li and C isotopes, offers a powerful tool to discriminate chemical weathering processes from sources of alteration during water-rock interactions under multi-lithology terrains. Reference: Rad, S., Rivé, K., Allègre, C.J., 2011. Weathering regime associated with subsurface circulation on volcanic islands. Aquat. Geochem. 17, 3, 221-241.

Rad, S.; Rive, K.; Assayag, N.; Dictor, M.; Garcin, M.

2012-12-01

87

Physical Processes Controlling Earth's Climate  

NASA Technical Reports Server (NTRS)

As background for consideration of the climates of the other terrestrial planets in our solar system and the potential habitability of rocky exoplanets, we discuss the basic physics that controls the Earths present climate, with particular emphasis on the energy and water cycles. We define several dimensionless parameters relevant to characterizing a planets general circulation, climate and hydrological cycle. We also consider issues associated with the use of past climate variations as indicators of future anthropogenically forced climate change, and recent advances in understanding projections of future climate that might have implications for Earth-like exoplanets.

Genio, Anthony Del

2013-01-01

88

A new CO 2 disposal process via artificial weathering of calcium silicate accelerated by acetic acid  

Microsoft Academic Search

A new disposal process for anthropogenic CO2 via an artificially accelerated weathering reaction is proposed to counteract global warming. The process is essentially composed of the following two steps:(1)CaSiO3+2CH3COOH?Ca2++2CH3COO?+H2O+SiO2(2)Ca2++2CH3COO?+CO2+H2O?CaCO3?+2CH3COOHStep (1) is the extraction of calcium ions by acetic acid from calcium silicate, for example, wollastonite rocks. Step (2) is the deposition of calcium carbonate from the solution of calcium ions

M. Kakizawa; A. Yamasaki; Y. Yanagisawa

2001-01-01

89

Process Physics: Inertia, Gravity and the Quantum  

E-print Network

Process Physics models reality as self-organising relational or semantic information using a self-referentially limited neural network model. This generalises the traditional non-process syntactical modelling of reality by taking account of the limitations and characteristics of self-referential syntactical information systems, discovered by Goedel and Chaitin, and the analogies with the standard quantum formalism and its limitations. In process physics space and quantum physics are emergent and unified, and time is a distinct non-geometric process. Quantum phenomena are caused by fractal topological defects embedded in and forming a growing three-dimensional fractal process-space. Various features of the emergent physics are briefly discussed including: quantum gravity, quantum field theory, limited causality and the Born quantum measurement metarule, inertia, time-dilation effects, gravity and the equivalence principle, a growing universe with a cosmological constant, black holes and event horizons, and the emergence of classicality.

Reginald T. Cahill

2001-10-29

90

Generation of abnormal trace element abundances in Antarctic eucrites by weathering processes  

SciTech Connect

Based on REEs, Antarctic eucrites can be divided into two groups: those showing normal trace element characteristics and those showing abnormal trace element abundances. Many Antarctic eucrite, polymict eucrite, and basaltic clast samples show the abnormal trace element abundances with REE patterns exhibiting positive Ce anomalies, positive Eu anomalies, and low abundances of the remainder of the REEs, with the LREEs generally being at lower relative abundances than the HREEs. We believe the unusual REE patterns of abnormal Antarctic eucrites arise from weathering effects generated in or on the Antarctic ice. Our suggested scenario involves formation of melt water and its equilibration in or on the Antarctic ice. Our suggested scenario involves formation of melt water and its equilibration with the atmosphere which promotes dissolution of REE-rich phosphates and oxidation of Ce. Tetravalent CE can then be fractionated from the trivalent REE in solution. The details of the weathering process are unclear and will require detailed chemical and SEM investigations of eucrites for their elucidation. We predict that rapidly chilled eucrites with glassy, rather than crystalline, mesostates will be more likely to survive the Antarctic environment without alteration of their REE patterns. Occasional S, Se, and K enrichments are likely due to weathering in the Antarctic environment as well, but these enrichments are not well correlated with Ce anomalies.

Mittlefehldt, D.W. (Lockheed ESC, Houston, TX (USA)); Lindstrom, M.M. (NASA/Johnson Space Center, Houston, TX (USA))

1991-01-01

91

Human information processing during physical exercise  

Microsoft Academic Search

This study was designed to investigate how conditions of physical exercise affect human information processing. Sixteen subjects performed two information processing tasks (perception and decision) during two exercise conditions (endurance vs interval protocols) and during two control conditions (rest vs minimal load protocols). The control conditions required subjects either to perform the information processing tasks under resting conditions or while

FRED G. W. C. PAAS; JOS J. ADAM

1991-01-01

92

Process Coupling Between Mineral Transformation and U Speciation in Acid Waste Weathered Sediments  

NASA Astrophysics Data System (ADS)

The need for better prediction of contaminant transport motivates multi-faceted lines of inquiry to build a strong bridge between molecular- and field-scale information. At Hanford (WA), millions of liters of U-containing acidic wastes have been discharged to the soil. In order to predict reactive contaminant migration in the soil, it is necessary to determine the process coupling that occurs between mineral transformation and uranium speciation in these acid-uranium waste weathered sediments. Furthermore, we seek to establish linkages between molecular-scale contaminant speciation and meso-scale contaminant lability, release and reactive transport. Unweathered Hanford sediments were reacted for 365 days with acidic (pH 3), uranium bearing waste solutions in batch experiments. The presence and absence of phosphate in the waste as a control on uranium speciation was also investigated. At dedicated reaction times (7, 14, 30, 90, 180 and 365 days) solid and solution chemistry were analyzed to determine weathering trajectories and contaminant speciation. As observed by XRD and U-EXAFS, when present, PO4 exerted a strong controls over uranium speciation at all pH with the rapid precipitation of meta-ankoleite [K(UO2PO4).3H2O] and near complete immobilization of U. Over prolonged reaction time, however, small fractions of boltwoodite [K(UO2)(HSiO4).3H2O] increased in PO4-high U systems. When PO4 was excluded from the reaction systems, U speciation was indirectly controlled by the pH of the reactant solution and its effect on primary mineral weathering. In this case, U immobilization remained limited with 25 to 50% of the uranium precipitated as becquerelite ([Ca(UO2)6O4(OH)6.3H2O] or the K equivalent - compreignacite) and suspected boltwoodite. Differences between the systems are attributed to process coupling between acid chemistry and U geochemistry. Carbonate weathering contributed to rapidly buffer the pH to pH 7-8 in the absence of PO4 and to 6-7 in its presence, promoting subsequent silicate weathering that makes aqueous Si available for boltwoodite precipitation. Comparison with homogeneous nucleation experiments and thermodynamic calculations confirmed the strong phosphate control over U speciation and the multispeciation of U in its absence.

Perdrial, N.; Kanematsu, M.; Wang, G.; Um, W.; O'Day, P. A.; Chorover, J.

2013-12-01

93

Physical Processes of Interstellar Turbulence  

E-print Network

I discuss the role of self-gravity and radiative heating and cooling in shaping the nature of the turbulence in the interstellar medium (ISM) of our galaxy. The heating and cooling cause it to be highly compressible, and, in some regimes of density and temperature, to become thermally unstable, tending to spontaneously segregate into warm/diffuse and cold/dense phases. On the other hand, turbulence is an inherently mixing process, tending to replenish the density and temperature ranges that would be forbidden under thermal processes alone. The turbulence in the ionized ISM appears to be transonic (i.e, with Mach numbers $\\Ms \\sim 1$), and thus to behave essentially incompressibly. However, in the neutral medium, thermal instability causes the sound speed of the gas to fluctuate by up to factors of $\\sim 30$, and thus the flow can be highly supersonic with respect to the dense/cold gas, although numerical simulations suggest that this behavior corresponds more to the ensemble of cold clumps than to the clumps'...

Vazquez-Semadeni, Enrique

2012-01-01

94

Getting Physical with the Digital Investigation Process  

Microsoft Academic Search

In this paper, a process model for digital investigations is defined using the theories and techniques from the physical investigation world. While digital investigations have recently become more common, physical investigations have existed for thousands of years and the experience from them can be applied to the digital world. This paper introduces the notion of a digital crime scene with

Brian D. Carrier; Eugene H. Spafford

2003-01-01

95

WHEAT KERNEL PHYSICAL PROPERTIES AND MILLING PROCESS  

Microsoft Academic Search

A b s t r a c t . Studies concerning the relations between wheat kernel physical properties and milling properties have been carried out since the beginning of the cereal processing industry. The aim of the present work was to show the application of the most important physical properties of wheat for the evaluation of wheat technological qua lity,

Dariusz Dziki; Janusz Laskowski

96

Physical Processes of Interstellar Turbulence  

E-print Network

I discuss the role of self-gravity and radiative heating and cooling in shaping the nature of the turbulence in the interstellar medium (ISM) of our galaxy. The heating and cooling cause it to be highly compressible, and, in some regimes of density and temperature, to become thermally unstable, tending to spontaneously segregate into warm/diffuse and cold/dense phases. On the other hand, turbulence is an inherently mixing process, tending to replenish the density and temperature ranges that would be forbidden under thermal processes alone. The turbulence in the ionized ISM appears to be transonic (i.e, with Mach numbers $\\Ms \\sim 1$), and thus to behave essentially incompressibly. However, in the neutral medium, thermal instability causes the sound speed of the gas to fluctuate by up to factors of $\\sim 30$, and thus the flow can be highly supersonic with respect to the dense/cold gas, although numerical simulations suggest that this behavior corresponds more to the ensemble of cold clumps than to the clumps' internal velocity dispersion. Finally, coherent large-scale compressions in the warm neutral medium (induced by, say, the passage of spiral arms or by supernova shock waves) can produce large, dense molecular clouds that are subject to their own self-gravity, and begin to contract gravitationally. Because they are populated by nonlinear density fluctuations, whose local free-fall times are significantly smaller than that of the whole cloud, the fluctuations terminate their collapse earlier, giving rise to a regime of hierarchical gravitational fragmentation, with small-scale collapses occurring within larger-scale ones. Thus, the "turbulence" in molecular clouds may be dominated by a gravitationally contracting component at all scales.

Enrique Vazquez-Semadeni

2012-02-20

97

Will Somebody do the Dishes? Weathering Analogies, Geologic Processes and Geologic Time  

NASA Astrophysics Data System (ADS)

A good analogy is one of the most powerful tools in any instructors' arsenal, and encouraging students to explore the links between an analogy and a scientific concept can cement both ideas in a student's mind. A common analogy for weathering and erosion processes is doing the dishes. Oxidation, hydration, and solution reactions can be intimidating on the chalkboard but easily understood in the context of cleaning up after dinner. Rather than present this analogy as a lecture demonstration, students are encouraged to experimentally determine which type of weathering works best on their dirty dishes. The experiment must use at least four identically dirty dishes: three experimental dishes and one control dish. The experimental dishes are subjected to simulated weathering and erosion processes of the student's design. Common techniques developed by students are cold or warm water baths, baths with and without acid (lemon juice or soda), and freeze-thaw cycles. Occasionally creative experiments result in unexpected discoveries, such the inefficiency of abrasion from wind-blown sand, especially when compared to soaking dishes in Canadian Whiskey. The effectiveness of each experimental run is determined by comparison to the control plate after loose debris is removed from each. The dish with the smallest aerial extent of remaining food is the declared the most effective. Discussion sections of the experimental write-up includes a description of which geologic processes were being simulated in each experiment, comparisons of the effectiveness of each techniques, and statements of how these experiments differ from reality. In order to advance this project, a second stage of the assignment, a direct comparison of weathering and erosion techniques on food and on geologic materials, will be added this fall. Ideally, students will empirically derive erosion rates and calculate the time required to remove the volume of material represented by a geologically important feature, such as Mt. Rainier or the Grand Canyon. In the end, students completing this project gain an understanding of how geologic processes work, the time scales required, the differences between analogies and the real thing, and arguably the most important aspect, a best-practices approach to doing the dishes.

Stelling, P.; Wuotila, S.; Giuliani, M.

2006-12-01

98

Favorite Demonstration: Differential Weathering  

NSDL National Science Digital Library

In this inquiry-based demonstration, the consumption of a Baby Ruth candy bar is used to nurture students' interest in chemical and physical weathering. In addition, two other concepts can be illustrated: the difference between weathering and erosion and

Francek, Mark

2002-10-01

99

Weathering and weathering rates of natural stone  

NASA Astrophysics Data System (ADS)

Physical and chemical weathering were studied as separate processes in the past. Recent research, however, shows that most processes are physicochemical in nature. The rates at which calcite and silica weather by dissolution are dependent on the regional and local climatic environment. The weathering of silicate rocks leaves discolored margins and rinds, a function of the rocks' permeability and of the climatic parameters. Salt action, the greatest disruptive factor, is complex and not yet fully understood in all its phases, but some of the causes of disruption are crystallization pressure, hydration pressure, and hygroscopic attraction of excess moisture. The decay of marble is complex, an interaction between disolution, crack-corrosion, and expansion-contraction cycies triggered by the release of residual stresses. Thin spalls of granites commonly found near the street level of buildings are generally caused by a combination of stress relief and salt action. To study and determine weathering rates of a variety of commercial stones, the National Bureau of Standards erected a Stone Exposure Test Wall in 1948. Of the many types of stone represented, only a few fossiliferous limestones permit a valid measurement of surface reduction in a polluted urban environment.

Winkler, Erhard M.

1987-06-01

100

Real-time storm detection and weather forecast activation through data mining and events processing  

Microsoft Academic Search

Each year across the United States, destructive weather events disrupt transportation and commerce, resulting in both loss of lives and property. Mitigating the impacts of such severe events requires innovative new software tools and cyberinfrastructure through which scientists can monitor data for specific weather events and launch focused modeling computations for prediction and forecasts of these evolving weather events. Bringing

Xiang Li; Beth Plale; Nithya N. Vijayakumar; Rahul Ramachandran; Sara J. Graves; Helen Conover

2008-01-01

101

Working Process Development For Weathering Degree Mapping Of Stone Monument Using Reflectance Spectroscopy  

Microsoft Academic Search

Most stone monuments have been weathered on the field with exposure of rain and wind during hundreds or thousands years. Reflectance spectroscopy can be applied to assess weathering degree of those stone monuments composed of granite which is the most general material of stone monument in Korea. Weathering degree was analyzed by using reflected and transmitted electromagnetic energy based on

C. Hyun

2008-01-01

102

Tires, Worms and Weathering: Investigating the Role of Earthworm Processes in Urban Soils Receiving Roadway Derived Contaminants  

NASA Astrophysics Data System (ADS)

Increased development around urban centers has altered the biogeochemistry of near surface systems. One major impact of development has been an increase in the availability of potentially toxic trace metals in soils and surface waters. A primary source of trace metals to near surface environments in urban systems is roadway runoff and dust. The potential hazard that roadway runoff and dust pose to biota is not well understood and is an area of extensive investigation in the multi-disciplinary field of environmental biogeochemistry. Because earthworms ingest, transport, process and excrete large amounts of soil on a daily basis, earthworms can have a profound impact on soil chemistry and the bioavailability of potentially toxic trace metals. Therefore, it is important to investigate how earthworms are affecting the distribution and bioavailability of potentially toxic metals in the soils that they re-work. Results from a set of mesocosm experiments using the native endogeic earthworm species Eisenoides loennbergi and soils from the Red Run watershed in Baltimore County, MD, exhibit evidence of the physical and chemical earthworm weathering processes over time periods as short as 3 week. The target element for this experiment was Zn which is highly enriched in roadway dust. In this study, 200 g of soil was amended with roadway dust. The total mass of Zn introduced was 20 mg making the target concentration 159 ppm. Six replicates were prepared with leaf litter added as a food source. Ten earthworms were then introduced into the soils. Two duplicate batches were then held at constant moisture (70%) and temperature (16 degrees C) for three weeks. An additional four were let run for six weeks. Control samples for both time periods show no change in either total Zn or extractable (1 M MgCl2) Zn concentration. The amended samples however, display evidence of extensive mixing and an increase in the extractable Zn that can be attributed to earthworm weathering processes. The results from this initial experimental work suggest that there is an important physical component to trace metal fate and transport in urban soils that is earthworm dominated and that earthworm processing can alter the extractable fraction of roadway dust.

Carroll, W.; Lev, S. M.; Szlavecz, K.; Landa, E. R.; Casey, R.; Snodgrass, J. W.

2006-05-01

103

Displaying Composite and Archived Soundings in the Advanced Weather Interactive Processing System  

NASA Technical Reports Server (NTRS)

This presentation describes work done by the Applied Meteorology Unit (AMU) to add composite soundings to the Advanced Weather Interactive Processing System (AWIPS). This allows National Weather Service (NWS) forecasters to compare the current atmospheric state with climatology. In a previous task, the AMU created composite soundings for four rawinsonde observation stations in Florida, for each of eight flow regimes. The composite soundings were delivered to the NWS Melbourne (MLB) office for display using the NSHARP software program. NWS MLB requested that the AMU make the composite soundings available for display in AWIPS. The AMU first created a procedure to customize AWIPS so composite soundings could be displayed. A unique four-character identifier was created for each of the 32 composite soundings. The AMIU wrote a Tool Command Language/Tool Kit (TclITk) software program to convert the composite soundings from NSHARP to Network Common Data Form (NetCDF) format. The NetCDF files were then displayable by AWIPS.

Barrett, Joe H., III; Volkmer, Matthew R.; Blottman, Peter F.; Sharp, David W.

2008-01-01

104

Water quality mapping and assessment, and weathering processes of selected aflaj in Oman.  

PubMed

There are more than 4,000 falaj (singular of a peculiar dug channel) distributed in different regions in Oman. The chemical characteristics of the water in 42 falaj were studied to evaluate the major ion chemistry; geochemical processes controlling water composition; and suitability of water for drinking, domestic, and irrigation uses. GIS-based maps indicate that the spatial distribution of chemical properties and concentrations vary within the same region and the different regions as well. The molar ratios of (Ca + Mg)/Total cations, (Na + K)/Total cations, (Ca + Mg)/(Na + K), (Ca + Mg)/(HCO? + SO?), and Na/Cl reveal that the water chemistry of the majority of aflaj are dominated by carbonate weathering and evaporite dissolution, with minor contribution of silicate weathering. The concentrations of most of the elements were less than the permissible limits of Omani standards and WHO guidelines for drinking water and domestic use and do not generally pose any health and environmental problems. Some aflaj in ASH Sharqiyah and Muscat regions can be used for irrigation with slight to severe restriction because of the high levels of electrical conductivity, total dissolved solids, chloride, and sodium absorption ratio. PMID:21210214

Ghrefat, Habes Ahmad; Jamarh, Ahmad; Al-Futaisi, Ahmed; Al-Abri, Badr

2011-10-01

105

Weather Forecasting  

NSDL National Science Digital Library

Weather Forecasting is a set of computer-based learning modules that teach students about meteorology from the point of view of learning how to forecast the weather. The modules were designed as the primary teaching resource for a seminar course on weather forecasting at the introductory college level (originally METR 151, later ATMO 151) and can also be used in the laboratory component of an introductory atmospheric science course. The modules assume no prior meteorological knowledge. In addition to text and graphics, the modules include interactive questions and answers designed to reinforce student learning. The module topics are: 1. How to Access Weather Data, 2. How to Read Hourly Weather Observations, 3. The National Collegiate Weather Forecasting Contest, 4. Radiation and the Diurnal Heating Cycle, 5. Factors Affecting Temperature: Clouds and Moisture, 6. Factors Affecting Temperature: Wind and Mixing, 7. Air Masses and Fronts, 8. Forces in the Atmosphere, 9. Air Pressure, Temperature, and Height, 10. Winds and Pressure, 11. The Forecasting Process, 12. Sounding Diagrams, 13. Upper Air Maps, 14. Satellite Imagery, 15. Radar Imagery, 16. Numerical Weather Prediction, 17. NWS Forecast Models, 18. Sources of Model Error, 19. Sea Breezes, Land Breezes, and Coastal Fronts, 20. Soundings, Clouds, and Convection, 21. Snow Forecasting.

Nielsen-Gammon, John

1996-09-01

106

SEVAN particle-detector network for Solar Physics and Space Weather research  

Microsoft Academic Search

A network of detectors called SEVAN (Space Environmental Viewing and Analysis Network) is planned in the framework of the International Heliophysical Year (IHY), to improve fundamental research of the Solar accelerators and Space Weather conditions. The network will detect changing fluxes of the most of species secondary cosmic rays at different altitudes, latitudes and altitudes those constituting powerful integrated device

A. Chilingarian; Ch. Angelov; K. Arakelyan; T. Arsov; K. Avakyan; S. Chilingaryan; A. Hovhannisyan; G. Hovsepyan; D. Hrzina; T. Hovhannisyan; D. Maricic; A. Nishev; A. Tchorbadjieff; I. Kalapov; T. Karapetyan; L. Kozliner; B. Mailyan; A. Reymers; I. Romstajn; D. Rosa; J. Stamenov; S. Tserunyan; A. Yeghikyan

2009-01-01

107

Weathering Experiments  

NSDL National Science Digital Library

This experiment is designed to allow students to observe and understand chemical and physical weathering of simulated "rocks". They will place the materials in plastic bags, one wet and one dry, and store them for 3-4 days. At the end of the storage period, they will observe the contents of both bags and answer some questions about what they see.

108

Identifying weathering processes by Si isotopes in two small catchments in the Black Forest (Germany)  

NASA Astrophysics Data System (ADS)

Stable Si isotopes are potentially an ideal proxy to investigate weathering as the release or precipitation of Si during abiotic or biotic processes causes significant shifts in the isotope signature depending on the weathering intensity. In this study, we determine the Si isotope signature of spring and stream waters and of the principle Si pools of typical soil profiles within two small catchments located on sandstone and paragneiss, respectively, in the cold, perhumid Black Forest (Germany). The Si isotope data were obtained on a Neptune MC-ICP-MS in solution for the water samples and in situ by coupling a UV femtosecond laser ablation system for solid samples, respectively. Bulk soils show a largely homogeneous Si isotope signature for different horizons and locations, which is close to those of bulk bedrocks with ?30Si value around -0.3‰. Soil clay formation is associated with limited Si mobility, which preserves initial Si isotope signatures of parental minerals. Biogenic mineral, i.e. phytoliths, exhibit negative Si isotope signature of about -0.4‰. An exception are the topsoil layers in the paragneiss catchment where the organic-rich environment promotes high Si mobility leading to a significant depletion of heavy Si isotopes. Springs and streams, sampled in spring and late summer, vary between -0.7 to 1.1‰ in ?30Si showing spatial and temporal variations dependent on the water pathways. Groundwater originated from sandstone and overlying periglacial debris layers reveals constant ?30Si values of 0.3 to 0.5‰, which is attributed to kaolinite formation. In contrast, water passing the soil zone shows very variable signatures. Low ?30Si values down to -0.7‰ most likely reflects dissolution processes of clay minerals and phytoliths during spring. In late summer, positive ?30Si values expose the impact of preferential uptake of light Si isotopes by plants. In the paragneiss catchment, this effect is likely increased by co-precipitation of isotopically light Si with Fe-oxides, which shifts surface water to ?30Si values up to 1.1‰. The Si isotope signature of the main stream depends on variable proportion of inflowing surface water and groundwater. The results on these small catchments demonstrate that Si isotopes are a powerful tool to identify weathering processes and the sources of dissolved Si, which can now be used to constrain the isotope signature of large river systems.

Steinhoefel, G.; Breuer, J.; von Blanckenburg, F.; Horn, I.; Kaczorek, D.; Sommer, M.

2013-12-01

109

Space plasma physics: I - Stationary processes  

NASA Technical Reports Server (NTRS)

The physics of stationary processes in space plasmas is examined theoretically in an introduction intended for graduate students. The approach involves the extensive use of numerical simulations. Chapters are devoted to fundamental principles, small-amplitude waves, and the stationary solar plasma system; typical measurement data and simulation results are presented graphically.

Hasegawa, Akira; Sato, Tetsuya

1989-01-01

110

Evolution of rotation in binaries: physical processes  

E-print Network

In this review, we describe the physical processes driving the dynamical evolution of binary stars, namely the circularization of the orbit and the synchronization of their spin and orbital rotation. We also discuss the possible role of the elliptic instability which turns out to be an unavoidable ingredient of the evolution of binary stars.

Michel Rieutord

2003-08-19

111

Studying the space weather variability of the high-latitude ionosphere by using a physics-based data assimilation model  

NASA Astrophysics Data System (ADS)

The high-latitude ionosphere is a very dynamic region in the solar-terrestrial environment. Frequent disturbances in the region can adversely affect numerous military and civilian technologies. Accurate specifications and forecasts of the high-latitude electrodynamic and plasma structures have fundamental space weather importance for enabling mitigation of adverse effects. We developed a data assimilation model for the high-latitude ionosphere. The model consists of a set of first-principle physical models and an ensemble Kalman filter and assimilates the real-time (or rear real-time) observational measurements. Presently, the model can ingest the magnetic perturbation from the ground-based magnetometers in the high-latitude regions, magnetic measurements of IRIDIUM satellites, SuperDARN line-of-sight velocity, and in-situ drift velocity measured by DMSP satellites. In this presentation, we will show the preliminary results of a systematic study of the space weather variability of the electrodynamic and plasma structures in the high-latitude ionosphere by using our data assimilation model. The study covers the periods of various seasons and geomagnetic conditions. With these results, we would demonstrate the dynamic nature of the high-latitude ionosphere and elucidate the importance of the data assimilation technique for accurate specification and forecasting of space weather.

Zhu, L.; Schunk, R. W.; Scherliess, L.; Eccles, J. V.; Sojka, J. J.

2012-12-01

112

Studying the space weather variability of the high-latitude ionosphere by using a physics-based data assimilation model  

NASA Astrophysics Data System (ADS)

The high-latitude ionosphere is a very dynamic region in the solar-terrestrial environment. Frequent disturbances in the region can adversely affect numerous military and civilian technologies. Accurate specifications and forecasts of the high-latitude electrodynamic and plasma structures have fundamental space weather importance for enabling mitigation of adverse effects. We developed a data assimilation model for the high-latitude ionosphere. The model consists of a set of first-principle physical models and an ensemble Kalman filter and assimilates the real-time (or rear real-time) observational measurements. Presently, the model can ingest the magnetic perturbation from the ground-based magnetometers in the high-latitude regions, magnetic measurements of IRIDIUM satellites, SuperDARN line-of-sight velocity, and in-situ drift velocity measured by DMSP satellites. In this presentation, we will show the preliminary results of a systematic study of the space weather variability of the electrodynamic and plasma structures in the high-latitude ionosphere by using our data assimilation model. The study covers the periods of various seasons and geomagnetic conditions. With these results, we would demonstrate the dynamic nature of the high-latitude ionosphere and elucidate the importance of the data assimilation technique for accurate specification and forecasting of space weather.

Zhu, Lie; Eccles, Vince; Scherliess, Ludger; Sojka, Jan J.; Schunk, Robert

2012-07-01

113

Analyzing the Role of Biofilm in Weathering Processes in the Rhizosphere with Various Microscopic Techniques  

NASA Astrophysics Data System (ADS)

Biofilm is thought to have a significant role in biological weathering of minerals in the rhizosphere (root systems). The goal of our study is to examine the characteristics of rhizospheric biofilms under a range of base cation limitations and determine the best microscopic techniques to analyze the biofilm-microbe-fungus-mineral interface. We hypothesized that tree-fungus-bacteria association increases biofilm formation under severe base cation limitations that enhance mineral weathering rate and improve potassium and calcium retention and transport to the trees. Our hypothesis was tested in samples from a growth column experiment. Red pine (Pinus resinosa) trees were grown in leach tubes in quartz sand amended with 1 wt% biotite and anorthite. Half of the trees were inoculated with Suillus tomentosus and a group of soil bacteria, and the other half were left without microbial inoculation. Columns without any biology added served as controls. Calcium and potassium were supplied in irrigation water in 0, 30, 60 and 100% of an amount for healthy tree growth and the concentration of all other nutrients stayed constant in all solutions. After four weeks, the columns were destructively sampled and the root systems were analyzed by various microscopic techniques such as helium ion microscopy (HeIM), scanning electron microscopy (SEM) coupled with focused ion beam (FIB) and energy dispersive x-ray spectroscopy (EDS), cryo-SEM, and high resolution transmission electron microscopy (TEM) also coupled with EDS. These techniques were employed to collect the most information about the biofilm-microbe-fungus-mineral interface. The HeIM uses a beam of helium ions to produce 3-D high resolution images with greater depth of field than SEM and produces detailed surface topography results. The SEM coupled with EDS gives detailed chemical distribution of elements on a surface topography. The SEM coupled with FIB produces a cross-section of the analyzed material and allows a view inside of the sample. It also allows preparing a thin section of a selected area, which could be transferred to the TEM for correlative imaging and analyses providing high resolution structural and chemical information of the biofilm-microbe-fungus-mineral interface. Using cryo-SEM complements the above results with preserving the specimen in its real, hydrated state that allows the characterization of the original topography and cross-section. The combinations of these state-of-the-art techniques shed new light on the characteristics of biofilm-microbe-fungus-mineral interface and provide information about weathering processes, rates, and base cation immobilization in soils.

Niedziela, S.; Greenberg, K. A.; Dohnalkova, A.; Arey, B.; Balogh-Brunstad, Z.

2011-12-01

114

Physical processes in spin polarized plasmas  

SciTech Connect

If the plasma in a nuclear fusion reactor is polarized, the nuclear reactions are modified in such a way as to enhance the reactor performance. We calculate in detail the modification of these nuclear reactions by different modes of polarization of the nuclear fuel. We also consider in detail the various physical processes that can lead to depolarization and show that they are by and large slow enough that a high degree of polarization can be maintained.

Kulsrud, R.M.; Valeo, E.J.; Cowley, S.

1984-05-01

115

Characterizing the process and quantifying the rate of subaerial rock weathering on desert surfaces using roughness analysis  

NASA Astrophysics Data System (ADS)

Subaerial weathering of rocks is a common process observed on desert surfaces on Earth and other planetary terrestrial surfaces such as on Mars. On Earth, this weathering process has been previously identified as one of the key erosion agent driving geomorphic surface evolution and the development of desert pavements. And yet, fundamental aspects of the process, such as the relative contribution of the different weathering modes that drive it (e.g., mechanical breakdown of rocks, chemical weathering, aeolian abrasion and exfoliation) as well as the rate by which this weathering process occurs have not been systematically examined. Here, we present a new approach for quantitatively addressing these fundamental aspects of process geomorphology on desert surfaces. We focus here on co-genetic desert alluvial surfaces of different ages, i.e. alluvial chronosequences, which provide excellent recorders for the evolution of boulder-strewn surfaces into smooth desert pavements through in-situ subaerial weathering of rocks. Our approach combines independent measures of two different surface attributes: High resolution (mm-scale) 3D ground-based laser scanning (LiDAR) of surface micro-topography, and numerical dating of surface age. Roughness analysis of the LiDAR data in power spectral density (PSD) space allows us to characterize the geometric manifestation of rock weathering on the surface and to distinguish between the different weathering modes. Numerical age constraints provide independent estimates for the time elapsed since the process began. Accordingly, we are able to constrain surface roughness evolution on alluvial fan desert chronosequences through time, and present PSD analysis of surface roughness as a new quantitative tool to examine the process of subaerial rock weathering in desert environments. In this study we present results from two late Quaternary alluvial chronosequences along the Dead Sea Transform in the hyper-arid Negev desert of southern Israel. LiDAR scanning was applied on representative areas (~30-50 m2) of 10 separate surfaces ranging from rough Holocene surfaces to fairly smooth surfaces with well-developed pavements displaying an OSL age of 87 kyr. We find typical and recurring time-dependent changes in the offset as well as shape of the PSD curves in both chronosequences: PSD offset is continuously reduced over time reflecting the overall reduction in the amplitude of roughness at all wavelengths. The PSD curves display progressive moderation of slopes at the longer wavelengths with the moderation point itself systematically shifted to shorter wavelengths. This characteristic evolution of PSD offset and slope moderation at longer wavelengths reflects the typical break up of boulder-sized clasts through time as the surfaces mature into well-developed desert pavements and points towards mechanical breakdown as the dominant weathering mode. In addition, we are able to determine the rate by which the larger clasts are removed from the system. We build on these new insights into process and rate of rock weathering to propose PSD analysis of surface roughness as a complementary method for constraining the age of desert alluvial surfaces in places where 'conventional' dating cannot be applied.

Mushkin, Amit; Sagy, Amir; Trabelci, Eran

2013-04-01

116

A robust vehicle detecting and tracking system for wet weather conditions using the IMAP-VISION image processing board  

Microsoft Academic Search

We present a robust vehicle detecting and tracking system for highway scenes of both dry and wet weather conditions taken from a forward-looking vehicle mounted camera. The system comprises the potential vehicle search, vehicle validation, and vehicle tracking processes. In order to overcome reduced visibility conditions, image normalization is performed automatically according to input image contrast and a weak edge

Sholin Kyo; Takuya Koga; Kazuyuki Sakurai; S. Okazaki

1999-01-01

117

Hands-on, online, and workshop-based K-12 weather and climate education resources from the Center for Multi-scale Modeling of Atmospheric Processes  

NASA Astrophysics Data System (ADS)

The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its fourth year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University (CSU) is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences. This is accomplished through collaborations in resource development and dissemination between CMMAP scientists, CSU’s Little Shop of Physics (LSOP) program, and the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). Little Shop of Physics develops new hands on science activities demonstrating basic science concepts fundamental to understanding atmospheric characteristics, weather, and climate. Videos capture demonstrations of children completing these activities which are broadcast to school districts and public television programs. CMMAP and LSOP educators and scientists partner in teaching a summer professional development workshops for teachers at CSU with a semester's worth of college-level content on the basic physics of the atmosphere, weather, climate, climate modeling, and climate change, as well as dozens of LSOP inquiry-based activities suitable for use in classrooms. The W2U project complements these efforts by developing and broadly disseminating new CMMAP-related online content pages, animations, interactives, image galleries, scientists’ biographies, and LSOP videos to K-12 and public audiences. Reaching nearly 20 million users annually, W2U is highly valued as a curriculum enhancement resource, because its content is written at three levels in English and Spanish. Links between science topics and literature, art, and mythology enable teachers of English Language Learners, literacy, and the arts to integrate science into their classrooms. In summary, the CMMAP NSF-funded Science and Technology Center has established a highly effective and productive partnership of scientists and educators focused on enhancing public science literacy about weather, climate, and global change. All CMMAP, LSOP, and W2U resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

Foster, S. Q.; Johnson, R. M.; Randall, D. A.; Denning, A.; Burt, M. A.; Gardiner, L.; Genyuk, J.; Hatheway, B.; Jones, B.; La Grave, M. L.; Russell, R. M.

2009-12-01

118

Clouds, weather, climate, and modeling for K-12 and public audiences from the Center for Multi-scale Modeling of Atmospheric Processes  

NASA Astrophysics Data System (ADS)

The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its fifth year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University (CSU) is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences. This is accomplished through collaborations in resource development and dissemination between CMMAP scientists, CSU’s Little Shop of Physics (LSOP) program, and the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). Little Shop of Physics develops new hands on science activities demonstrating basic science concepts fundamental to understanding atmospheric characteristics, weather, and climate. Videos capture demonstrations of children completing these activities which are broadcast to school districts and public television programs. CMMAP and LSOP educators and scientists partner in teaching a summer professional development workshops for teachers at CSU with a semester's worth of college-level content on the basic physics of the atmosphere, weather, climate, climate modeling, and climate change, as well as dozens of LSOP inquiry-based activities suitable for use in classrooms. The W2U project complements these efforts by developing and broadly disseminating new CMMAP-related online content pages, animations, interactives, image galleries, scientists’ biographies, and LSOP videos to K-12 and public audiences. Reaching nearly 20 million users annually, W2U is highly valued as a curriculum enhancement resource, because its content is written at three levels in English and Spanish. Links between science topics and literature, art, and mythology enable teachers of English Language Learners, literacy, and the arts to integrate science into their classrooms. In summary, the CMMAP NSF-funded Science and Technology Center has established a highly effective and productive partnership of scientists and educators focused on enhancing public science literacy about weather, climate, and global change. All CMMAP, LSOP, and W2U resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

Foster, S. Q.; Johnson, R. M.; Randall, D. A.; Denning, A.; Russell, R. M.; Gardiner, L. S.; Hatheway, B.; Jones, B.; Burt, M. A.; Genyuk, J.

2010-12-01

119

Day Length and Weather Effects on Children's Physical Activity and Participation in Play, Sports, and Active Travel  

PubMed Central

Background Children in primary school are more physically active in the spring/summer. Little is known about the relative contributions of day length and weather, however, or about the underlying behavioral mediators. Methods 325 British children aged 8 to 11 wore accelerometers as an objective measure of physical activity, measured in terms of mean activity counts. Children simultaneously completed diaries in which we identified episodes of out-of-home play, structured sports, and active travel. Our main exposure measures were day length, temperature, rainfall, cloud cover, and wind speed. Results Overall physical activity was higher on long days (? 14 hours daylight), but there was no difference between short (< 9.5 hours) and medium days (10.2–12.6 hours). The effect of long day length was largest between 5 PM and 8 PM, and persisted after adjusting for rainfall, cloud cover, and wind. Up to half this effect was explained by a greater duration and intensity of out-of-home play on long days; structured sports and active travel were less affected by day length. Conclusions At least above a certain threshold, longer afternoon/evening daylight may have a causal role in increasing child physical activity. This strengthens the public health arguments for daylight saving measures such as those recently under consideration in Britain. PMID:22826506

Goodman, Anna; Paskins, James; Mackett, Roger

2013-01-01

120

Pb isotope systematics in volcanic river system: Constraints about weathering processes  

NASA Astrophysics Data System (ADS)

We present a series of lead isotopes in soils and sediments developed on volcanic rocks forming a small watershed flowing through the Massif Central (France). The Massif Central volcanic province is a widespread area of Tertiary to Recent continental alkaline volcanism comprising alkali basalts and basanites. The Allanche watershed has an area of 160 km2, a maximum altitude in the watershed of 1400 m (a.s.l.) and the relief between the extreme sampling points of 340 m The river is 29 km long from headwaters to the outlet and from its origin in the Cézallier area to its mouth in the Allagnon river (a tributary of the Allier river), the Allanche river flows through the volcanic terrains of the lava plateau (11 to 2.5 Ma). Main bedrocks are basanites (nepheline or leucitic basalts), with SiO2 around 41-45%, low Na2O + K2O (<5%), and with modal or normative nepheline or leucite and a ground mass of clinopyroxene and plagioclase. Surrounding rocks are feldspatic basalts with SiO2 close to 46-49%, low Na2O + K2O (<5%). The main phase in these basalts is plagioclase with normative nepheline, hyperstene and olivine. Crustal contamination (e.g. by granite, gneiss or metasedimentary granulite, as stated by Downes, 1987, doi: 10.1144/GSL.SP.1987.030.01.25) has occurred in the differentiated magmas of both series, as witnessed by lead isotopic variations in conjunction with Rb/La ratios and lead contents. Using Pb isotope ratios, major and trace elements (from Négrel and Deschamps, 1996, Aquatic Geochemistry, 2, 1-27) we therefore compare sediments and soils evolution over the Allanche river watershed. K and Ca are considered as mobile reference elements and illustrate the weathering state of soils and sediments relative to parent rocks through a large decrease in K and Ca content when compared to Si; the sediments being less depleted than soils. Lead, with regards to Si shows three behaviour with depleted Si content- same lead content that bedrock, depleted Si content- less lead content and depleted Si content - high lead content that bedrock. The comparison of 1000Pb/K versus Si/K ratio evidenced the evolution line from weathering processes and the lead enrichment from atmospheric deposition as a major contributor to explain the deviation of several points from this line. Lead isotopes decrease from bedrock to sediments-soils without any clear relationship when compared to lead contents. The use of Pb-isotopic compositions showed that most of the lead budget in sediments and soils result from bedrock weathering with an influence of gasoline additive-lead derived inputs and a lack of lead input from agricultural activities.

Negrel, P. J.; Millot, R.; Petelet-Giraud, E.; Guerrot, C.

2012-12-01

121

Effects Of Fungal-Mineral Interactions On Chemical Weathering And Denudation Processes - Observations From Experimental Ecosystems  

Microsoft Academic Search

A mesoscale (`sandbox') lysimeter experiment was performed at Hubbard Brook Experimental Forest, New Hampshire, to study plant-growth influences on chemical weathering and chemical denudation. Weathering was estimated by mass balance for 5 and 15-year intervals, and denudation was monitored as the product of drainage flow and concentration for 20 years in large (7.5x7.5x1.5m) fully lined sandboxes a.) planted with red

Z. Balogh; C. Keller; J. Dickinson

2003-01-01

122

Physics of a random biological process  

NASA Astrophysics Data System (ADS)

We analyze the successive fluctuations of the daytime and nighttime sleep pattern of a newborn baby by using tools of far-from-equilibrium statistical physics. We find that this class of natural random biological process displays a remarkable long-range power-law correlation that extends for, at least, the first six months of life. Such a scaling behavior might help to characterize the underlying dynamics of the (early) growth and development of humans through analyzing the time series generated when asleep.

Canessa, E.; Calmetta, A.

1994-07-01

123

Protein Folding as a Physical Stochastic Process  

E-print Network

We model protein folding as a physical stochastic process as follows. The unfolded protein chain is treated as a random coil described by SAW (self-avoiding walk). Folding is induced by hydrophobic forces and other interactions, such as hydrogen bonding, which can be taken into account by imposing conditions on SAW. The resulting model is termed CSAW (conditioned self-avoiding walk. Conceptually, the mathematical basis is a generalized Langevin equation. In practice, the model is implemented on a computer by combining SAW and Monte Carlo. To illustrate the flexibility and capabilities of the model, we consider a number of examples, including folding pathways, elastic properties, helix formation, and collective modes.

Kerson Huang

2007-07-17

124

Novel natural and anthropogenic physical mechanisms of weather and climate changes  

NASA Astrophysics Data System (ADS)

A unified approach is suggested to the problem of impact of both space and several anthropogenic sources on the weather and climate changes. The united agent of this impact is examined i.e. microwave emission of the ionosphere, which resulted from ionospheric atoms and molecules excitation into highly excited (Rydberg) states by fast ionospheric electrons. Fast electrons with the energies more than 15 eV are formed with the photoionization of the upper atmosphere under the effect of X-ray/EUV solar radiation and with the ionization of the corpuscular precipitations from the radiation belts and magnetosphere both during of geomagnetic storms and under the anthropogenic influences. The latter (the work of powerful navigation and communication radio stations (because the most of them induce very low frequency (VLF) range: from few to few tens kilo Hertz.), electric power lines, starting space rockets, industrial activity) determines the locality of precipitations and accordingly the local action of the microwave radiation of the ionosphere on the weather characteristics. Surface transmitters with such frequency have power up to 1 Mw that cause precipitations and result in optical emission (the aurora of the class IBC II or more) above the transmitter. Indeed results of measurements performed by the satellites Intercosmos-Bulgaria 1300 at 1982 and DEMETER at 2005 confirm very high extent of disturbance of radiation belts and night ionosphere above the zone of work of VLF transmitters both in Northern Hemisphere (transmitters NLK, NAA in USA and UMS, RPS in Russia), and in Southern Hemisphere (transmitter NWC) especially during geomagnetic disturbances. Areas of stimulated electron precipitations and areas of perturbed ionosphere are linked either with the magnetic force line at which the surface VHL transmitter is situated or with the magnetic line at which effect of radio wave on the pitch angle of electron, captured in radiation belt, takes place. This area of stimulated perturbations reaches a half of million of square kilometers. Every time perturbations of lesser scale are observed in magnetic conjugate area. In accordance with our calculations the rate of ionization and excitation of ionosphere in the conjugate point and hence, generation of microwave radiation from Rydberg states reaches 10 % of the effect in the point of the transmitter work. We suggest three-stage radio-optical trigger mechanism for the ionospheric microwaves influence on the weather and climate. The first stage is an increase in generation of the microwave radiation which penetrates from the ionosphere to the earth surface. The second stage is a change in the proportion of water vapour to water clusters caused by increased microwave radiation. The third stage is a change of the atmosphere transparence in the absorption bands of water vapour and clusters. The atmosphere transparence due to cloudiness (usually optically thin (warming) clouds from solar flares and corpuscular of both natural and technological precipitations) determines fluxes of solar irradiance coming down as well as fluxes of the thermal radiation coming out from the underlying surface. The maximum of secular cycles of solar activity was observed in eighties of last century. Since 1985 the total solar irradiance and ionizing radiation fluxes have been decreasing but geomagnetic activity (aa - index) has been going up till 2003. Only during the last few years geomagnetic activity also started decreasing. This means that negative trends have begun both for solar and geomagnetic activities, and also there is a positive trend of GCR since 1998 which participate in generation of optically thick (cooling) clouds. We suppose that according to our mechanism the natural global warming will go down to lower levels.

Voronin, Nikolai; Avakyan, Sergei

2010-05-01

125

Doing It In The SWMF Way: From Separate Space Physics Simulation Programs To The Framework For Space Weather Simulation.  

NASA Astrophysics Data System (ADS)

The NASA-funded Space Weather Modeling Framework (SWMF) is developed to provide "plug and play" type Sun-to-Earth simulation capabilities serving the space physics modeling community. In its fully developed form, the SWMF will comprise a series of interoperating models of physics domains, ranging from the surface of the Sun to the upper atmosphere of the Earth. In its current form the SWMF links together five models: Global Magnetosphere, Inner Heliosphere, Ionosphere Electrodynamics, Upper Atmosphere, and Inner Magnetosphere. The framework permits to switch models of any type. The SWMF is a structured collection of software building blocks that can be used or customized to develop Sun-Earth system modeling components, and to assemble them into application. The SWMF consist of utilities and data structures for creating model components and coupling them. The SWMF contains Control Model, which controls initialization and execution of the components. It is responsible for component registration, processor layout for each component and coupling schedules. A component is created from the user-supplied physics code by adding a wrapper, which provides the control functions and coupling interface to perform the data exchange with other components. Both the wrapper and coupling interface are constructed from the building blocks provided by the framework itself. The current SWMF implementation is based on the latest component technology and uses many important concepts of Object-Oriented Programming emulated in Fortran 90. Currently it works on Linux Beowulf clusters, SGI Origin 2000 and Compaq ES45 machines.

Volberg, O.; Toth, G.; Sokolov, I.; Ridley, A. J.; Gombosi, T. I.; de Zeeuw, D. C.; Hansen, K. C.; Chesney, D. R.; Stout, Q. F.; Powell, K. G.; Kane, K. J.; Oehmke, R. C.

2003-12-01

126

Displaying Composite and Archived Soundings in the Advanced Weather Interactive Processing System  

NASA Technical Reports Server (NTRS)

In a previous task, the Applied Meteorology Unit (AMU) developed spatial and temporal climatologies of lightning occurrence based on eight atmospheric flow regimes. The AMU created climatological, or composite, soundings of wind speed and direction, temperature, and dew point temperature at four rawinsonde observation stations at Jacksonville, Tampa, Miami, and Cape Canaveral Air Force Station, for each of the eight flow regimes. The composite soundings were delivered to the National Weather Service (NWS) Melbourne (MLB) office for display using the National version of the Skew-T Hodograph analysis and Research Program (NSHARP) software program. The NWS MLB requested the AMU make the composite soundings available for display in the Advanced Weather Interactive Processing System (AWIPS), so they could be overlaid on current observed soundings. This will allow the forecasters to compare the current state of the atmosphere with climatology. This presentation describes how the AMU converted the composite soundings from NSHARP Archive format to Network Common Data Form (NetCDF) format, so that the soundings could be displayed in AWl PS. The NetCDF is a set of data formats, programming interfaces, and software libraries used to read and write scientific data files. In AWIPS, each meteorological data type, such as soundings or surface observations, has a unique NetCDF format. Each format is described by a NetCDF template file. Although NetCDF files are in binary format, they can be converted to a text format called network Common data form Description Language (CDL). A software utility called ncgen is used to create a NetCDF file from a CDL file, while the ncdump utility is used to create a CDL file from a NetCDF file. An AWIPS receives soundings in Binary Universal Form for the Representation of Meteorological data (BUFR) format (http://dss.ucar.edu/docs/formats/bufr/), and then decodes them into NetCDF format. Only two sounding files are generated in AWIPS per day. One file contains all of the soundings received worldwide between 0000 UTC and 1200 UTC, and the other includes all soundings between 1200 UTC and 0000 UTC. In order to add the composite soundings into AWIPS, a procedure was created to configure, or localize, AWIPS. This involved modifying and creating several configuration text files. A unique fourcharacter site identifier was created for each of the 32 soundings so each could be viewed separately. The first three characters were based on the site identifier of the observed sounding, while the last character was based on the flow regime. While researching the localization process for soundings, the AMU discovered a method of archiving soundings so old soundings would not get purged automatically by AWl PS. This method could provide an alternative way of localizing AWl PS for composite soundings. In addition, this would allow forecasters to use archived soundings in AWIPS for case studies. A test sounding file in NetCDF format was written in order to verify the correct format for soundings in AWIPS. After the file was viewed successfully in AWIPS, the AMU wrote a software program in the Tool Command Language/Tool Kit (Tcl/Tk) language to convert the 32 composite soundings from NSHARP Archive to CDL format. The ncgen utility was then used to convert the CDL file to a NetCDF file. The NetCDF file could then be read and displayed in AWIPS.

Barrett, Joe H., III; Volkmer, Matthew R.; Blottman, Peter F.; Sharp, David W.

2008-01-01

127

Commercializing Space Weather using GAIM  

NASA Astrophysics Data System (ADS)

Space weather's effects upon the near-Earth environment are due to dynamic changes in the en-ergy transfer processes from the Sun's photons, particles, and fields. Of the space environment domains that are affected by space weather, the ionosphere is the key region that affects com-munication and navigation systems. The Utah State University (USU) Space Weather Center (SWC) was organized in 2009 to develop commercial space weather applications. It uses the Global Assimilation of Ionospheric Measurements (GAIM) system as the basis for providing improvements to communication and navigation systems. For example, in August 2009 SWC released, in conjunction with Space Environment Technologies, the world's first real-time space weather via an iPhone app, Space WX. It displays the real-time, current global ionosphere to-tal electron content along with its space weather drivers, is available through the Apple iTunes store, and is used around the world. The GAIM system is run operationally at SWC for global and regional (continental U.S.) conditions. Each run stream continuously ingests up to 10,000 slant TEC measurements every 15-minutes from approximately 500 stations in a Kalman filter to adjust the background output from the physics-based Ionosphere Forecast Model (IFM). Additionally, 80 real-time digisonde data streams from around the world provide ionosphere characterization up to the F-region peak. The combination of these data dramatically improves the current epoch ionosphere specification beyond the physics-based solution. The altitudinal range is 90-1500 km for output TEC, electron densities, and other data products with a few degrees resolution in latitude and longitude at 15-minute time granularity. We describe the existing SWC products that are used as commercial space weather information. SWC funding is provided by the State of Utah's Utah Science Technology and Research (USTAR) initiative. The SWC is physically located on the USU campus in Logan, Utah.

Tobiska, W. Kent; Schunk, Robert; Sojka, Jan J.

128

Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal - a review  

Microsoft Academic Search

Rapid turnover of organic matter leads to a low efficiency of organic fertilizers applied to increase and sequester C in soils of the humid tropics. Charcoal was reported to be responsible for high soil organic matter contents and soil fertility of anthropogenic soils (Terra Preta) found in central Amazonia. Therefore, we reviewed the available information about the physical and chemical

Bruno Glaser; Johannes Lehmann; Wolfgang Zech

2002-01-01

129

Soil dehydrogenase activity adjacent to remedially treated timber, weathered in a physical field model  

Microsoft Academic Search

Three physical field models were constructed to assess the effects on soil of a chromated fluoride wood preservative treatment used at the groundline of creosoted electricity distribution poles. One model contained an untreated aged creosoted pole section in sandy loam soil, the second contained a remedially treated aged creosoted pole section in sandy loam soil and the third a similarly

D. C. R. Sinclair; G. M. Smith; A. Bruce; H. J. Staines

1997-01-01

130

Weather and Road Management  

NSDL National Science Digital Library

Anticipating and dealing with weather and the hazards it creates is a real challenge for those in departments of transportation. This module gives road and highway managers a basic understanding of meteorology and weather hazards so that they can better interpret weather forecast information used to make road management decisions. The module also highlights web-based forecast products available from the National Weather Service that can help in the decision-making process.

Comet

2008-07-21

131

Bringing life to soil physical processes  

NASA Astrophysics Data System (ADS)

When Oklahoma's native prairie grass roots were replaced by corn, the greatest environmental (and social) disaster ever to hit America ensued. The soils lost structure, physical binding by roots was annihilated and when drought came the Great Dust Bowl commenced. This form of environmental disaster has repeated over history and although not always apparent, similar processes drive the degradation of seemingly productive farmland and forests. But just as negative impacts on biology are deleterious to soil physical properties, positive impacts could reverse these trends. In finding solutions to soil sustainability and food security, we should be able to exploit biological processes to improve soil physical properties. This talk will focus on a quantitative understanding of how biology changes soil physical behaviour. Like the Great Dust Bowl, it starts with reinforcement mechanisms by plant roots. We found that binding of soil by cereal (barley) roots within 5 weeks of planting can more than double soil shear strength, with greater plant density causing greater reinforcement. With time, however, the relative impact of root reinforcement diminishes due to root turnover and aging of the seedbed. From mechanical tests of individual roots, reasonable predictions of reinforcement by tree roots are possible with fibre bundle models. With herbaceous plants like cereals, however, the same parameters (root strength, stiffness, size and distribution) result in a poor prediction. We found that root type, root age and abiotic factors such as compaction and waterlogging affect mechanical behaviour, further complicating the understanding and prediction of root reinforcement. For soil physical stability, the interface between root and soil is an extremely important zone in terms of resistance of roots to pull-out and rhizosphere formation. Compounds analogous to root exudates have been found with rheological tests to initially decrease the shear stress where wet soils flow, but after decomposition of these exudates by microbes the shear stress increases. This suggests an initial dispersion, followed by aggregation of the soil, which explains the structural arrangement of soil particles in the rhizosphere observed by microscopy. Dispersion of soil minerals in the root zone is important to release bound nutrients from mineral surfaces. Using fracture mechanics we measured large impacts of biological exudates on the toughness and interparticle bond energy of soils. Now novel tests are being developed to quantify interparticle bonding by biological exudates on single and multiple particle contacts, including mechanical test specimens that can be inoculated with specific bacteria or fungi. This will allow for clay mineralogy, water potential and solution chemistry impacts on interparticle bonding to be quantified directly. Wettability experiments with the same samples measure hydrological properties such as contact angle. Basic information from these tests will help explain biological processes that drive soil structure formation and stabilisation, providing data for models of soil structure dynamics.

Hallett, P. D.

2013-12-01

132

Digital Signal Processing applied to Physical Signals  

E-print Network

It is well known that many of the scientific and technological discoveries of the XXI century will depend on the capability of processing and understanding a huge quantity of data. With the advent of the digital era, a fully digital and automated treatment can be designed and performed. From data mining to data compression, from signal elaboration to noise reduction, a processing is essential to manage and enhance features of interest after every data acquisition (DAQ) session. In the near future, science will go towards interdisciplinary research. In this work there will be given an example of the application of signal processing to different fields of Physics from nuclear particle detectors to biomedical examinations. In Chapter 1 a brief description of the collaborations that allowed this thesis is given, together with a list of the publications co-produced by the author in these three years. The most important notations, definitions and acronyms used in the work are also provided. In Chapter 2, the last r...

Alberto, Diego; Musa, L

2011-01-01

133

Severe and Unusual Weather METR 2603, Sec 001  

E-print Network

descriptive account of the physical processes important in the formation of various severe and unusual weather phenomena including: thunderstorms, tornadoes, hail and conditions. 3. Develop an understanding of the causes, formation, evolution and impacts

Droegemeier, Kelvin K.

134

Physical processes in collapse driven supernova  

SciTech Connect

A model of the supernova explosion is discussed. The method of neutrino transport is discussed, since the explosive mechanism depends on neutrino heating of the material behind the accretion shock. The core region of these exploding stars becomes unstable to convective motions during the supernova evolution. Convective mixing allows more neutrinos to escape from under the neutrinosphere, and thus increases the amount of heating by neutrinos. An approximate method of incorporating convection is described, and some results of including convection in a computer model is presented. Another phenomena is seen in computer simulations of supernova, oscillations in the neutrino luminosity and mass accretion rate onto the protoneutron star. The last topic discussed in this thesis describes the attempt to understand this oscillation by perturbation of the steady state solution to equations approximating the complex physical processes occurring in the late time supernova. 42 refs., 31 figs.

Mayle, R.W.

1985-11-01

135

Perubahan Sifat Fisik dan Mekanik Panel Zephyr Bambu setelah Uji Pelapukan Cuaca The Change of Physical and Mechanical Properties of Zephyr Bamboo Panel after Exposed to Outdoor Weathering  

Microsoft Academic Search

The objective of this study is to evaluate the physical and mechanical properties of zephyr bamboo panel after exposed to outdoor weathering for 12 months. The zephyr bamboo panel is bamboo board which was made from crushed bamboo in bamboo-crushing machine to produce zephyr, the panel was made for exterior type, and the thickness was 18 mm. The adhesive used

Mohamad Gopar; Yanni Sudiyani

136

Application of GIS for processing and establishing the correlation between weather radar reflectivity and precipitation data  

Microsoft Academic Search

Correlation between weather radar reflectivity and precipitation data collected by rain gauges allows empirical formulae to be obtained that can be used to create continuous rainfall surfaces from discrete data. Such surfaces are useful in distributed hydrologic modelling and early warning systems in flood management. Because of the spatial relationship between rain gauge locations and radar coverage area, GIS provides

Y. Gorokhovich; G. Villarini

2005-01-01

137

Studying the Space Weather Features of the High-Latitude Ionosphere by Using a Physics-Based Data Assimilation Model and Observational Data from Ground Magnetometer Arrays  

NASA Astrophysics Data System (ADS)

The high-latitude ionosphere is a very dynamic region in the solar-terrestrial environment. Frequent disturbances in the region can adversely affect numerous military and civilian technologies. Accurate specifications and forecasts of the high-latitude electrodynamic and plasma structures have fundamental space weather importance for enabling mitigation of adverse effects. Presently, most of the space-weather models use limited observations and/or indices to define a set of empirical drivers for physical models to move forward in time. Since the empirical drivers have a "climatological" nature and there are significant physical inconsistencies among various empirical drivers due to independent statistical analysis of different observational data, the specifications of high-latitude space environment from these space weather models cannot truthfully reflect the weather features. In fact, unrealistic small- and large-scale structures could be produced in the specifications and forecasts from these models. We developed a data assimilation model for the high-latitude ionospheric plasma dynamics and electrodynamics to overcome these hurdles. With a set of physical models and an ensemble Kalman filter, the data assimilation model can determine the self-consistent structures of the high-latitude convection electric field, ionospheric conductivity, and the key drivers associated with these quantities by ingesting data from multiple observations. These ingested data include the magnetic perturbation from the ground-based magnetometers in the high-latitude regions, magnetic measurements of IRIDIUM satellites, SuperDARN line-of-sight velocity, and in-situ drift velocity measured by DMSP satellites. As a result, the assimilation model can capture the small- and large-scale plasma structures and sharp electrodynamic boundaries, thus, can provide a more accurate picture of the high-latitude space weather. In this presentation, we will first briefly describe the data-assimilation model of high-latitude electrodynamics and its strengths over the other space-weather models. Then we will present the space weather features produced by the model for quiet and storm periods constrained by the data from ground magnetometer arrays. This will demonstrate the dynamic variability of the high-latitude ionosphere. Finally, we will present high-resolution ionospheric modeling results of the time-evolution and spatial features of the high-latitude plasma structures to further demonstrate the model's capability in producing the space weather features in the high-latitude ionosphere. These results will illuminate the importance of real-time data availability and data assimilation models for accurate specification and forecasting of space weather.

Zhu, L.; Schunk, R. W.; Scherliess, L.; Sojka, J. J.; Eccles, J. V.

2011-12-01

138

Physical processes in EUV sources for microlithography  

NASA Astrophysics Data System (ADS)

The source is an integral part of an extreme ultraviolet lithography (EUVL) tool. Such a source, as well as the EUVL tool, has to fulfil very high demands both technical and cost oriented. The EUVL tool operates at a wavelength of 13.5 nm, which requires the following new developments. The light production mechanism changes from conventional lamps and lasers to relatively high-temperature emitting plasmas. The light transport, mainly refractive for deep ultraviolet (DUV), should be reflective for EUV. The source specifications as derived from the customer requirements on wafer throughput mean that the output EUV source power has to be hundreds of watts. This in its turn means that tens to hundreds of kilowatts of dissipated power has to be managed in a relatively small volume. In order to keep lithography costs as low as possible, the lifetime of the components should be as long as possible and at least of the order of thousands of hours. This poses a challenge for the sources, namely how to design and manufacture components robust enough to withstand the intense environment of high heat dissipation, flows of several keV ions as well as the atomic and particular debris within the source vessel. As with all lithography tools, the imaging requirements demand a narrow illumination bandwidth. Absorption of materials at EUV wavelengths is extreme with extinguishing lengths of the order of tens of nanometres, so the balance between high transmission and spectral purity requires careful engineering. All together, EUV lithography sources present technological challenges in various fields of physics such as plasma, optics and material science. These challenges are being tackled by the source manufacturers and investigated extensively in the research facilities around the world. An overview of the published results on the topic as well as the analyses of the physical processes behind the proposed solutions will be presented in this paper.

Banine, V. Y.; Koshelev, K. N.; Swinkels, G. H. P. M.

2011-06-01

139

Weather Vane  

NSDL National Science Digital Library

In this meteorology activity, learners build weather vanes using straws, paperclips, and cardstock. Learners will explore wind and air resistance as well as how weather vanes are used to understand and predict weather.

Workshop, Fresno C.

2011-01-01

140

Weather Watch  

ERIC Educational Resources Information Center

Suggests a number of ways in which Federal Aviation Agency weather report printouts can be used in teaching the weather section of meteorology. These weather sequence reports can be obtained free of charge at most major airports. (JR)

Bratt, Herschell Marvin

1973-01-01

141

Physics as an Enterprise of Process Philosophy  

ERIC Educational Resources Information Center

Physics, as a discipline, attempts to discern the mysteries of physical universe and it is also an inspiration for technological innovations which contribute to the good or demise of human civilization. While it continues to have tremendous impact on the technological front, one wonders if physics, as an enterprise engaged in providing a coherent…

Rangacharyulu, Chary

2005-01-01

142

Space Weathering of Apollo 16 Sample 62255: Lunar Rocks as Witness Plates for Deciphering Regolith Formation Processes  

NASA Technical Reports Server (NTRS)

Space weathering, or alteration that occurs at the surfaces of materials exposed directly to space, has been one of the primary areas of focus of lunar studies for the past several years. It is caused by processes such as micrometeorite impacts and solar wind bombardment, and effects can include microcraters, spall zones, and vapor deposits. Much of the recent work on space weathering has been concentrated on nanoscale features, especially the amorphous rims commonly found on individual lunar soil grains. The rims typically contain nanophase Fe metal globules, which, along with Fe metal globules in agglutinates, have a profound effect on optical properties of lunar soils. The nanophase metallic iron globules cause the characteristic optical changes (reddening and darkening) found in mature lunar soils.

Wentworth, S. J.; McKay, D. S.; Keller, L. P.

2004-01-01

143

Anvil Forecast Tool in the Advanced Weather Interactive Processing System, Phase II  

NASA Technical Reports Server (NTRS)

Meteorologists from the 45th Weather Squadron (45 WS) and Spaceflight Meteorology Group have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violations of the Lightning Launch Commit Criteria and Space Light Rules. As a result, the Applied Meteorology Unit (AMU) created a graphical overlay tool for the Meteorological Interactive Data Display Systems (MIDDS) to indicate the threat of thunderstorm anvil clouds, using either observed or model forecast winds as input.

Barrett, Joe H., III

2008-01-01

144

Proton computed tomography from multiple physics processes  

NASA Astrophysics Data System (ADS)

Proton CT (pCT) nowadays aims at improving hadron therapy treatment planning by mapping the relative stopping power (RSP) of materials with respect to water. The RSP depends mainly on the electron density of the materials. The main information used is the energy of the protons. However, during a pCT acquisition, the spatial and angular deviation of each particle is recorded and the information about its transmission is implicitly available. The potential use of those observables in order to get information about the materials is being investigated. Monte Carlo simulations of protons sent into homogeneous materials were performed, and the influence of the chemical composition on the outputs was studied. A pCT acquisition of a head phantom scan was simulated. Brain lesions with the same electron density but different concentrations of oxygen were used to evaluate the different observables. Tomographic images from the different physics processes were reconstructed using a filtered back-projection algorithm. Preliminary results indicate that information is present in the reconstructed images of transmission and angular deviation that may help differentiate tissues. However, the statistical uncertainty on these observables generates further challenge in order to obtain an optimal reconstruction and extract the most pertinent information.

Bopp, C.; Colin, J.; Cussol, D.; Finck, Ch; Labalme, M.; Rousseau, M.; Brasse, D.

2013-10-01

145

Sr isotopes as a tracer of weathering processes and dust inputs in a tropical granitoid watershed, Luquillo Mountains, Puerto Rico  

NASA Astrophysics Data System (ADS)

Sr isotope data from soils, water, and atmospheric inputs in a small tropical granitoid watershed in the Luquillo Mountains of Puerto Rico constrain soil mineral development, weathering fluxes, and atmospheric deposition. This study provides new information on pedogenic processes and geochemical fluxes that is not apparent in watershed mass balances based on major elements alone. 87Sr/ 86Sr data reveal that Saharan mineral aerosol dust contributes significantly to atmospheric inputs. Watershed-scale Sr isotope mass balance calculations indicate that the dust deposition flux for the watershed is 2100 ± 700 mg cm -2 ka -1. Nd isotope analyses of soil and saprolite samples provide independent evidence for the presence of Saharan dust in the regolith. Watershed-scale Sr isotope mass balance calculations are used to calculate the overall short-term chemical denudation velocity for the watershed, which agrees well with previous denudation rate estimates based on major element chemistry and cosmogenic nuclides. The dissolved streamwater Sr flux is dominated by weathering of plagioclase and hornblende and partial weathering of biotite in the saprock zone. A steep gradient in regolith porewater 87Sr/ 86Sr ratio with depth, from 0.70635 to as high as 0.71395, reflects the transition from primary mineral-derived Sr to a combination of residual biotite-derived Sr and atmospherically-derived Sr near the surface, and allows multiple origins of kaolinite to be identified.

Pett-Ridge, Julie C.; Derry, Louis A.; Kurtz, Andrew C.

2009-01-01

146

Severe Weather  

ERIC Educational Resources Information Center

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This month's insert, Severe Weather, has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in this poster are hurricanes,…

Forde, Evan B.

2004-01-01

147

Severe Weather  

ERIC Educational Resources Information Center

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This article deals with a poster entitled, "Severe Weather," that has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in…

Forde, Evan B.

2004-01-01

148

UM Weather  

NSDL National Science Digital Library

Sponsored by The Weather Underground at the University of Michigan at Ann Arbor, UM Weather bills itself as the "Internet's premier source of weather information." The site offers several general audience tools such as the Fast Forecast for any city in the US, ski weather, and weather cams. But, it also provides access to over two dozen weather software packages, a new computer model forecasts page, and most impressively a list of close to 400 other weather related Web sites. Professionals and researchers will appreciate the non-technical feel of the site and the valuable information they can procure from it.

1994-01-01

149

Avalanche Weather Forecasting  

NSDL National Science Digital Library

Avalanches form through the interaction of snowpack, terrain, and weather, the latter being the focus of this module. The module begins with basic information about avalanches, highlighting weather's role in their development. The rest of the module teaches weather forecasters how to make an avalanche weather forecast, that is, one in which key weather parameters are evaluated for their impact on avalanche potential. The forecasts are used primarily by avalanche forecasters, who integrate them with other information to determine when to issue avalanche hazard warnings. The module contains five cases that let users apply the avalanche weather forecast process to different combinations of snowpack, terrain, and weather conditions. It is a companion to the COMET module "Snowpack and Its Assessment," which describes snowpack development and various assessment techniques.

Comet

2010-09-30

150

Weathering in a Cup.  

ERIC Educational Resources Information Center

Two easy student activities that demonstrate physical weathering by expansion are described. The first demonstrates ice wedging and the second root wedging. A list of the needed materials, procedure, and observations are included. (KR)

Stadum, Carol J.

1991-01-01

151

Physical and Chemical Changes in the Digestion Process  

NSDL National Science Digital Library

This lesson demonstrates how students can determine the cause and effect relationship in the digestion process. Students will be able to determine where chemical and physical changes occur in the digestion process and support their findings from an informational text. This lesson provides students with an opportunity to apply their knowledge of physical and chemical changes in matter to the process of digestion.

Clark, Monica

2012-09-16

152

Weathering of Minerals  

NSDL National Science Digital Library

Students determine the % change in mass of mineral samples that have been placed in a rock tumbler. They graph the relationship between the hardness of the mineral and the % change in mass. They then consider why some of the mineral samples do not conform the the relationship they graphed. They investigate the physical properties of the outliers and consider how the physical properties contributed to the rate of weathering, and what kind of weathering occured in the rock tumbler.

Van Norden, Wendy

153

Weather Forecasting for Radio Astronomy  

E-print Network

Weather Forecasting for Radio Astronomy Part I: The Mechanics and Physics Ronald J Maddalena August 1, 2008 #12;Outline Part I Background -- research inspirations and aspirations Vertical weather, .... Part II Results on refraction & air mass (with Jeff Paradis) Part III Results on opacity, weather

Groppi, Christopher

154

Enabling Effective Space Weather and Climatology (SWaC) Capabilities: The NRC Decadal Survey in Solar and Space Physics  

NASA Astrophysics Data System (ADS)

The U.S. very much needs long-term observations of the space weather environment and must support the development and application of coupled space weather models to protect critical societal infrastructure, including communication, navigation, and terrestrial weather satellites. As just one example, solar and space physicists partnering with power grid engineers have created the capability to model the effects of geomagnetically-induced currents on electricity transmission and distribution systems. This crucially important work has produced sophisticated software to assess the response of the electrical power system to geomagnetic storms, to assess the vulnerabilities, and to develop mitigation strategies. To fulfill the requirements for space weather presented in the June 2010 U.S. National Space Policy and envisioned in the 2010 National Space Weather Program Plan, we must develop a new approach. The National Research Council's 2013-2022 Decadal Survey presents a vision for renewed national commitment to a comprehensive program in Space Weather and Climatology, building on agency strengths. Enabling an effective SWaC capability will require action across multiple agencies. To coordinate the development of this plan, the National Space Weather Program should be re-chartered under the auspices of the National Science and Technology Council and include active participation from the Office of Science and Technology Policy and the Office of Management and Budget. The plan should take into account current agency efforts and capabilities, leverage the new capabilities and knowledge that will arise from implementation of the Decadal Survey, and develop additional monitoring capabilities and platforms specifically tailored to space weather monitoring and prediction.

Baker, D. N.

2012-12-01

155

WWW - Wonderful Web Weather  

NSDL National Science Digital Library

This is a web quest for students to research weather forecasting using the Internet. Students work in groups to study how accurate weather forecasts are by tracking the weather for 3 days in several locations. Using graphs students then compare how each location scored in accuracy and present their findings to the class. This site contains links for students to use for more background information, a process for the students to follow, and evaluation rubrics for the student-produced graphs and presentation.

Parrish, Jason

2007-12-12

156

OpenWeather: a peer-to-peer weather data transmission protocol  

Microsoft Academic Search

The study of the weather is performed using instruments termed weather stations. These weather stations are distributed around the world, collecting the data from the different phenomena. Several weather organizations have been deploying thousands of these instruments, creating big networks to collect weather data. These instruments are collecting the weather data and delivering it for later processing in the collections

Adrian Yanes

2011-01-01

157

Surface Processes Lab Department of Physics & Astronomy  

E-print Network

Unlimited US Geological Survey Blue Ridge RD&C IEEE American Geophysical Union American Physical Society ASU;SPL ­ Collaborations / Funding / Partnerships / Memberships Geological Society of America Water Resources Research Institute Environmental Protection Agency NCDENR NC Sea Grant Clean Water Management

Thaxton, Christopher S.

158

Humps and hollows: basalt weathering in low-latitude mountains  

NASA Astrophysics Data System (ADS)

Physical, chemical and biological weathering processes are significant contributors to landscape development in mountain blocks worldwide, and over long time scales, but the interplay between different weathering processes is uncertain. Jurassic-age basalt lava flows underlie the Drakensberg mountain range of eastern Lesotho, southern Africa (summits 3200-3400 m asl), and weathered bedrock is commonly exposed on flat plateau surfaces. Subaerial weathering throughout the Quaternary and Holocene has resulted in a range of weathering forms, some of which exploit pre-existing cooling fractures within the basalts, and some of which are independent of geological control. These forms include pseudokarst-style potholes, karren and other microforms. The geometry, chemistry of water contained within the potholes, seasonal presence of ice, sediment and organic residues all suggest that physical, chemical and biological weathering processes are significant at different times and in different ways in subaerial weathering. Moreover, it is also likely that these process-types show pronounced seasonal variability that means that the interplay between different processes is subtle. Aggregated rates of land surface denudation or geomorphic development of single landforms therefore hide this subtle interplay between different processes. Changes in mountain summit soil depth (through soil erosion), ecosystems and climate will change this balance between different processes, and will operate over different spatial and temporal scales.

Knight, Jasper; Grab, Stefan

2013-04-01

159

Space Weathering in the Inner Solar System  

NASA Technical Reports Server (NTRS)

"Space weathering" is the term given to the cumulative effects incurred by surfaces which are exposed to the harsh environment of space. Lunar sample studies over the last decade or so have produced a clear picture of space weathering processes in the lunar environment. By combining laboratory and remote spectra with microanalytical methods (scanning and transmission electron microscopy), we have begun to unravel the various processes (irradiation, micrometeorite bombardment, etc) that contribute to space weathering and the physical and optical consequences of those processes on the Moon. Using the understanding gleaned from lunar samples, it is possible to extrapolate weathering processes to other airless bodies from which we have not yet returned samples (i.e. Mercury, asteroids). Through experiments which simulate various components of weathering, the expected differences in environment (impact rate, distance from Sun, presence of a magnetic field, reduced or enhanced gravity, etc) and composition (particularly iron content) can be explored to understand how space weathering will manifest on a given body.

Noble, Sarah K.

2010-01-01

160

Wide variability in physical activity environments and weather-related outdoor play policies in child-care centers within a single county of Ohio  

PubMed Central

Objectives To examine the variability of physical activity environments and outdoor play-policies in child-care centers, and to determine if they are associated with center demographic characteristics Design Telephone survey—the Early Learning Environments Physical Activity and Nutrition Telephone Survey (ELEPhANTS) Setting Child-care centers in Hamilton County (Cincinnati area), Ohio, 2008–9. Participants Directors of all 185 licensed full-time child-care centers in Hamilton County. Outcome Measures Descriptive measures of center playground and indoor physical activity environments, and weather-related outdoor-play policies. Results 162 (88%) centers responded. Most (93%) centers reported an on-site playground, but only half reported their playgrounds as large, at least 1/3rd covered in shade, or having a variety of portable play equipment. Only half reported having a dedicated indoor gross-motor room where children could be active during inclement weather. Only 20% of centers allowed children to go outside in temperatures below 32°F, and 43% of centers reported allowing children outdoors during light rain. A higher percent of children receiving tuition-assistance was associated with lower quality physical activity facilities and stricter weather-related practices. National accreditation was associated with more physical-activity promoting practices. Conclusion We found considerable variability in the indoor and outdoor playground offerings among child-care centers, even within a single county of Ohio. Per center policy and limited inside options, children’s active opportunities are curtailed due to sub-freezing temperatures or light rain. Policy change and parent/teacher education may be needed to ensure children achieve ample opportunity for daily physical activity. PMID:21199969

Copeland, Kristen A; Sherman, Susan N; Khoury, Jane C; Foster, Karla E; Saelens, Brian E; Kalkwarf, Heidi J

2011-01-01

161

A New Perspective on Surface Weather Maps  

ERIC Educational Resources Information Center

A two-dimensional weather map is actually a physical representation of three-dimensional atmospheric conditions at a specific point in time. Abstract thinking is required to visualize this two-dimensional image in three-dimensional form. But once that visualization is accomplished, many of the meteorological concepts and processes conveyed by the…

Meyer, Steve

2006-01-01

162

Terrestrial-marine teleconnections in the Devonian: links between the evolution of land plants, weathering processes, and marine anoxic events  

PubMed Central

The Devonian Period was characterized by major changes in both the terrestrial biosphere, e.g. the evolution of trees and seed plants and the appearance of multi-storied forests, and in the marine biosphere, e.g. an extended biotic crisis that decimated tropical marine benthos, especially the stromatoporoid-tabulate coral reef community. Teleconnections between these terrestrial and marine events are poorly understood, but a key may lie in the role of soils as a geochemical interface between the lithosphere and atmosphere/hydrosphere, and the role of land plants in mediating weathering processes at this interface. The effectiveness of terrestrial floras in weathering was significantly enhanced as a consequence of increases in the size and geographic extent of vascular land plants during the Devonian. In this regard, the most important palaeobotanical innovations were (1) arborescence (tree stature), which increased maximum depths of root penetration and rhizoturbation, and (2) the seed habit, which freed land plants from reproductive dependence on moist lowland habitats and allowed colonization of drier upland and primary successional areas. These developments resulted in a transient intensification of pedogenesis (soil formation) and to large increases in the thickness and areal extent of soils. Enhanced chemical weathering may have led to increased riverine nutrient fluxes that promoted development of eutrophic conditions in epicontinental seaways, resulting in algal blooms, widespread bottomwater anoxia, and high sedimentary organic carbon fluxes. Long-term effects included drawdown of atmospheric pCO2 and global cooling, leading to a brief Late Devonian glaciation, which set the stage for icehouse conditions during the Permo-Carboniferous. This model provides a framework for understanding links between early land plant evolution and coeval marine anoxic and biotic events, but further testing of Devonian terrestrial-marine teleconnections is needed.

Algeo, T. J.

1998-01-01

163

Radiogenic and stable isotope variations accompanying continental weathering  

NASA Astrophysics Data System (ADS)

Many natural isotope systems, both stable and radiogenic, are sensitive to variations in weathering processes, but the difficulty remains in distinguishing variations that result from weathering from those caused by differences in rock type. One approach that circumvents this problem is the study of monolithologic catchments, where variations in physical and chemical weathering rates, runoff, catchment age, vegetative and glacial cover can be related to river chemistry. This study presents an overview of our recent work on radiogenic and stable isotopes in rivers and estuaries from Iceland, draining basaltic terrains, where variations in glacial cover result in a wide range of weathering conditions. Each radiogenic and stable isotope system reveals complementary information on the nature of the weathering process, and the estuarine data indicates how this signal is transferred to the oceans. For the dissolved riverine phase, in the absence of variations in rock type, the principal controls on isotope variations accompanying weathering are; (i) For many radiogenic isotope systems, preferential (incongruent) weathering of specific mineral phases, where those phases possess a markedly different parent/daughter ratio, and hence radiogenic isotope composition; (ii) For many stable isotope systems, preferential removal of an isotope into secondary phases formed during weathering, leaves residual waters depleted in that isotope. Despite the wide range of isotope compositions in the dissolved load, for Iceland it is the nature of weathering of the suspended load in the estuarine environment that likely dominates the signal to the oceans. Moreover, both the flux and nature of the suspended load are highly dependent on riverine discharge, and hence climate change. These results clearly demonstrate that weathering processes can exert a significant influence on the riverine isotope signal to the oceans, and for some isotopes marine sedimentary archives will preserve a record of changes in weathering in response to climatic or tectonic change. The challenge remains in deconvolving the effects of weathering from those caused by variations in rock type, or a simple change in the weathering flux.

Burton, K. W.; Gannoun, A.; Georg, B.; Gislason, S. R.; James, R. H.; Parkinson, I. J.; Pogge von Strandmann, P. A.; Mokadem, F.

2007-12-01

164

What similar physical processes occur on both Earth and Mars?  

NSDL National Science Digital Library

This NASA Module investigation compares and contrasts physical processes that occur on Both Earth and Mars. Students are given unidentified images of Earth and Mars. Their task is to arrange the images into pairs that show evidence of similar physical processes. Then they identify each image as one of Earth or of Mars by comparing and contrasting physical features that they observe in the image pairs. It includes teacher background materials and an answer key where appropriate.

2002-05-26

165

Plasma physics of processing discharges. Memorandum report  

Microsoft Academic Search

Plasma processing has grown into a tremendously important industrial capability over the last 20 years, and has done so with virtually no input from traditional plasma physicists. Plasma processing is important in such areas as nanocircuit fabrication, diamond thin film deposition, superconducting film deposition, and nanocube production and deposition. Undoubtedly there are other users in the laboratory also. There are

Manheimer

1992-01-01

166

The plasma physics of processing discharges  

Microsoft Academic Search

Plasma processing has grown into a tremendously important industrial capability over the last 20 years, and has done so with virtually no input from traditional plasma physicists. Plasma processing is important in such areas as nanocircuit fabrication, diamond thin film deposition, superconducting film deposition, and nanocube production and deposition. Undoubtedly there are other users in the laboratory also. There are

W. M. Manheimer

1992-01-01

167

Weather Forecasting  

NSDL National Science Digital Library

This website, supplied by Annenberg / CPB, discusses weather satellites, Doppler radar, and additional tools forecasters use to predict the weather. Students can find a wind chill calculator along with a brief discussion of the history of forecasting and weather lore. Once you have a firm grasp on the science of weather forecasting, be sure to check out the other sections of this site, which include: "ice and snow," "our changing climate," "the water cycle," and "powerful storms."

2008-03-27

168

Significance of physical weathering of two-texturally different soils for the saturated transport of Escherichia coli and bromide.  

PubMed

This study was carried out to investigate the transport of Escherichia coli NAR and bromide (Br) through repacked (R) and weathered (W) soil columns. A suspension containing E. coli NAR and Br were leached and the effluent from the weathered soil columns had greater contaminant concentrations than that from the repacked soil columns. The time to the concentration peak of (C(max)) E. coli NAR and Br increased in the order CL-W < SL-W < SL-R < CL-R. The breakthrough sequence suggests the formation of a heterogeneous soil pore network induced by weathering and the importance of accelerated flow in the weathered columns. The dual-permeability model in HYDRUS-1D software was used to simulate the E. coli NAR and Br transport parameters by inverse modeling. Parameters of the attachment-detachment model were calculated using the dual-permeability model parameters fitted to the BTCs of E. coli NAR. A greater attachment coefficient associated with soil repacking and the finer textured clayey soil demonstrated the importance of adsorbent site and smaller pore spacing in these treatments. Smaller attachment and adsorption isotherm coefficients in weathered soil columns suggest the need for further research to validate this as a predictive model for the risks for vadose zone contaminant transport. PMID:22647706

Safadoust, A; Mahboubi, A A; Mosaddeghi, M R; Gharabaghi, B; Voroney, P; Unc, A; Khodakaramian, Gh

2012-09-30

169

Antarctic Weather  

NSDL National Science Digital Library

Visitors to this site can read a discussion about the weather in Anarctica, including why it is so cold, how weather observations are conducted there, and what role the continent plays in the global weather system. Links to related topics, a wind chill calculator, and a Fahrenheit-Celsius-Kelvin temperature converter are also provided.

170

Space Weathering of Rocks  

NASA Technical Reports Server (NTRS)

Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.

Noble, Sarah

2011-01-01

171

Home Weatherization Visit  

SciTech Connect

Secretary Steven Chu visits a home that is in the process of being weatherized in Columbus, OH, along with Ohio Governor Ted Strickland and Columbus Mayor Michael Coleman. They discuss the benefits of weatherization and how funding from the recovery act is having a direct impact in communities across America.

Chu, Steven

2009-01-01

172

Erosion and Weathering  

NSDL National Science Digital Library

Weathering and erosion work together as natural forces, removing and transporting material. Sediments, the by-products of these processes, are subsequently deposited to produce characteristic landforms such as dunes, deltas, and glacial moraines. This slide show presents images of landforms that result from erosion and weathering, as well as measures designed to mitigate their unwanted effects.

173

Foundations of Physical Theory, I: Force and Energy. Physical Processes in Terrestrial and Aquatic Ecosystems, Fundamentals.  

ERIC Educational Resources Information Center

This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module is one of two units on the foundations of physical theory and the…

Pearson, Nolan E.

174

Evaluating the effects of terrestrial ecosystems, climate and carbon dioxide on weathering over geological time: a global-scale process-based approach  

PubMed Central

Global weathering of calcium and magnesium silicate rocks provides the long-term sink for atmospheric carbon dioxide (CO2) on a timescale of millions of years by causing precipitation of calcium carbonates on the seafloor. Catchment-scale field studies consistently indicate that vegetation increases silicate rock weathering, but incorporating the effects of trees and fungal symbionts into geochemical carbon cycle models has relied upon simple empirical scaling functions. Here, we describe the development and application of a process-based approach to deriving quantitative estimates of weathering by plant roots, associated symbiotic mycorrhizal fungi and climate. Our approach accounts for the influence of terrestrial primary productivity via nutrient uptake on soil chemistry and mineral weathering, driven by simulations using a dynamic global vegetation model coupled to an ocean–atmosphere general circulation model of the Earth's climate. The strategy is successfully validated against observations of weathering in watersheds around the world, indicating that it may have some utility when extrapolated into the past. When applied to a suite of six global simulations from 215 to 50 Ma, we find significantly larger effects over the past 220 Myr relative to the present day. Vegetation and mycorrhizal fungi enhanced climate-driven weathering by a factor of up to 2. Overall, we demonstrate a more realistic process-based treatment of plant fungal–geosphere interactions at the global scale, which constitutes a first step towards developing ‘next-generation’ geochemical models. PMID:22232768

Taylor, Lyla L.; Banwart, Steve A.; Valdes, Paul J.; Leake, Jonathan R.; Beerling, David J.

2012-01-01

175

The influence of regional urbanization and abnormal weather conditions on the processes of human climatic adaptation on mountain resorts  

NASA Astrophysics Data System (ADS)

This work is a further development in the study of weather pathogenic index (WPI) and negative influence of urbanization processes on the state of people's health with adaptation disorder. This problem is socially significant. According to the data of the WHO, in the world there are from 20 to 45% of healthy people and from 40 to 80% of people with chronic diseases who suffer from the raised meteosensitivity. As a result of our researches of meteosensitivity of people during their short-duration on mountain resorts there were used negative adaptive reactions (NAR) under 26 routine tests, stress-reactions under L.H. Garkavi's hemogram, vegetative indices, tests of neuro-vascular reactivity, signs of imbalance of vegetative and neurohumoral regulation according to the data of biorhythm fractal analysis and sudden aggravations of diseases (SAD) as an indicator of negative climatic and urbanization influence. In 2010-2011 the Caucasian mountain resorts were having long periods of climatic anomalies, strengthening of anthropogenic emissions and forest fires when record-breaking high waves of NAR and SAD were noticed. There have also been specified indices ranks of weather pathogenicity from results of comparison of health characteristics with indicators of synoptico-dynamic processes according to Weather Research and Forecasting model (WRF); air ionization N+, N-, N+/N- spectra of aerosol particles (the size from 500 to 20000 nanometers) and concentrations of chemically active gases (O3, NO, NO2, ), volatile phytoorganic substances in the surface atmosphere, bactericidal characteristics of vegetation by criterion ?2 (not above 0,05). It has allowed us to develop new physiological optimum borders, norm and pessimum, to classify emergency ecologo-weather situations, to develop a new techniques of their forecasting and prevention of meteopathic reactions with meteosensitive patients (Method of treatment and the early (emergency) and planned prevention meteopatic reactions in patients with coronary heart disease, hypertension stage I-II syndrome disadaptative using the transcranial mezo diencephalic modulation / L.I.Zherlitsina, N.V. Efimenko, N.P. Povolotskaya, I.I. Velikanov. the Patent for the invention No.2422128, RU (11) 2 422 128 (13) C1 from 6/27/2011; Bull.13). We have observed that such anthropogenic characteristics as accumulation of aerosol with the size of particles 500-5000 nanometers in the lower atmosphere in the quantity more than 60 particles/sm3 (getting to alveoli); decrease in quantity of negative ions (N-) lower than 200 ions/sm3, high coefficient of ions unipolarity (N+/N-) - more than 4-6; mass concentration of aerosol more than 150 mkg/m3 and other modules of the environment can act as limited markers for the forecast of dangerous NAR, SAD and taking of urgent radical preventive measures. These techniques of medical weather forecast and meteo prevention can be used in other mountain regions of the world. The studies were performed by support of the Program "Basic Sciences for Medicine" and RFBR project No.10-05-01014_a.

Artamonova, M.; Golitsyn, G.; Senik, I.; Safronov, A.; Babyakin, A.; Efimenko, N.; Povolotskaya, N.; Topuriya, D.; Chalaya, E.

2012-04-01

176

TIME SERIES ANALYSIS OF REMOTELY-SENSED TIR EMISSION: linking anomalies to physical processes  

NASA Astrophysics Data System (ADS)

In the last 15 years, remote sensing has been evaluated for detecting thermal anomalies as precursor to earthquakes. Important issues that need yet to be tackled include definition of: (a) thermal anomaly, taking into account weather conditions, observation settings and ';natural' variability caused by background sources (b) the length of observations required for this purpose; and (c) the location of detected anomalies, which should be physically related to the tectonic activity. To determine whether thermal anomalies are statistical noise, mere meteorological conditions, or actual earthquake-related phenomena, we apply a novel approach. We use brightness temperature (top-of-atmosphere) data from thermal infrared imagery acquired at a hypertemporal (sub-hourly) interval, from geostationary weather satellites over multiple years. The length of the time series allows for analysis of meteorological effects (diurnal, seasonal or annual trends) and background variability, through the application of a combined spatial and temporal filter to distinguish extreme occurrences from trends. The definition of potential anomalies is based on statistical techniques, taking into account published (geo)physical characteristics of earthquake related thermal anomalies. We use synthetic data to test the performance of the proposed detection method and track potential factors affecting the results. Subsequently, we apply the method on original data from Iran and Turkey, in quiescent and earthquake-struck periods alike. We present our findings with main focus to assess resulting anomalies in relation to physical processes thereby considering: (a) meteorological effects, (b) the geographical, geological and environmental settings, and (c) physically realistic distances and potential physical relations with the activity of causative faults.

Pavlidou, E.; van der Meijde, M.; Hecker, C.; van der Werff, H.; Ettema, J.

2013-12-01

177

Severe Weather  

NSDL National Science Digital Library

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. The National Weather Service (NWS)--which is part of NOAA and its parent agency, the Department of Commerce--is charged with the critical responsibility of observing and reporting the weather and with issuing forecasts and warnings of weather and floods in the interest of national safety and economy. Through a massive network of weather-monitoring and reporting stations around the globe, including land, sea, air, and space-borne instruments, NWS scientists constantly assimilate all of the reliable weather data available. Much of this data are then used in numerical computer models of the atmosphere that help to accurately describe and interpret current conditions and produce the best possible forecasts of future weather.

Forde, Evan B.

2004-04-01

178

Physical processes at high field strengths  

SciTech Connect

Measurements of the radiation produced by the high field interaction with the rare gases have revealed the presence of both copious harmonic production and fluorescence. The highest harmonic observed was the seventeenth (14.6 rm) in Ne, the shortest wavelength ever produced by that means. Strong fluorescence was seen in Ar, Kr, and Xe with the shortest wavelengths observed being below 10 nm. Furthermore, radiation from inner-shell excited configurations in Xe, specifically the 4d/sup 9/5s5p ..-->.. 4d/sup 10/5s manifold at approx. 17.7 nm, was detected. The behaviors of the rare gases with respect to multiquantum ionization, harmonic production, and fluorescence were found to be correlated so that the materials fell into two groups, He and Ne in one and Ar, Kr, and Xe in the other. These experimental findings, in alliance with other studies on inner-shell decay processes, give evidence for a role of atomic correlations in a direct nonlinear process of inner-shell excitation. It is expected that an understanding of these high-field processes will enable the generation of stimulated emission in the x-ray range. 59 refs., 6 figs., 5 tabs.

Rhodes, C.K.

1986-01-01

179

Biogenic catalysis in sulphide minerals' weathering processes and acid mine drainage genesis.  

PubMed

Bioleaching and biogenesis are the main outputs from a large group of environmental processes participating in the natural material cycle, used in raw materials processing. Bio-oxidation reactions are the main basis for bioleaching procedures, often participating in parallel leaching processes. During the leaching processes of polycomponent sulphide substrates, the factor of process selection also plays an important role, being in direct relation to the electric properties and galvanic effect occurring between the individual components of the leaching substrate. This work gives a summary of the results of a research focused on the possibilities of using biotechnological procedures for treatment of Slovak sulphide ores. The object of the research is extraction of valuable metals, undesirable admixtures and degradation of crystal lattice of sulphides for subsequent chemical leaching processing of precious metals. The results of experiments on the existence of biogenic processes in situ on waste dumps from exploitation containing residual sulphides are also presented. The processes result in acid mine drainage water generation. These waters are strongly mineralised (over 48 g/L) and of low pH; that is why they are very caustic. The arsenic content (2.558 mg/L) in outflowing waters from old mines is high and over the limits set by the law. PMID:24445359

Kušnierová, Mária; Praš?áková, Mária; Nowak, Anna K; Gorazda, Katarzyna; Wzorek, Zbigniew

2014-01-01

180

Coupling physical processes in simulations of chemically reactive flows  

Microsoft Academic Search

The exact way the processes are coupled depends on the individual properties of the different algorithms used and the regimes in which the competing physical processes interact. In particular, we have found that the best form of the coupling to use varies according to whether the convection is treated by an implicit or explicit approach. Other processes may be done

E. Oran; J. Boris; K. Kailasanath; G. Patnaik

181

Coupling physical processes in simulations of chemically reactive flows  

Microsoft Academic Search

The exact way the processes are coupled depends on the individual properties of the different algorithms used and the regimes in which the competing physical processes interact. In particular, we have found that the best form of the coupling to use varies according to whether the convection is treated by an implicit or explicit approach. Other processes may be done

E. S. Oran; J. P. Boris; K. Kailasanath; G. Patnaik

1989-01-01

182

Quantum speed limit for physical processes.  

PubMed

The evaluation of the minimal evolution time between two distinguishable states of a system is important for assessing the maximal speed of quantum computers and communication channels. Lower bounds for this minimal time have been proposed for unitary dynamics. Here we show that it is possible to extend this concept to nonunitary processes, using an attainable lower bound that is connected to the quantum Fisher information for time estimation. This result is used to delimit the minimal evolution time for typical noisy channels. PMID:23414007

Taddei, M M; Escher, B M; Davidovich, L; de Matos Filho, R L

2013-02-01

183

Physical processes mediating climate impacts in shelf sea ecosystems  

NASA Astrophysics Data System (ADS)

How global scale climate change might impact coastal and shelf seas is far from straightforward. A myriad of physical processes can potentially act as vectors transferring the larger scale oceanic and atmospheric variability and change to shelf sea physics, biogeochemistry and lower trophic level ecosystems. These act on a wide range of time scales, being strongly dependent on the prevailing conditions of an individual shelf sea basin. Examples of the physical processes include upper ocean warming, seasonal/permanent stratification, wind mixing, convective mixing, light climate, terrestrial input, circulation and ocean-shelf exchange. These potentially impact ecosystem processes such as primary production, plankton community structured, bloom timing, and mid-water production. However, different processes often act in a different sense and are not necessarily additive, leading to damping or amplification effects. During the MEECE project (www.meece.eu) we conducted a series of coordinated downscaled coupled physics-ecosystem model experiments to explore these issues. Here, we review the prevailing physical processes, contrasting five very different shelf sea regions: North Sea, Celtic seas, Baltic Sea, Black sea and Barents Sea, using results from three different model systems: POLCOMS-ERSEM, ECOSMO, BIMS-ECO. Using this ensemble of simulations, along with process sensitivity studies and multiple forcing studies, we are able to identify which physical processes are important in which region, and how they interact. This builds up a picture of contrasting vulnerability of these regions to different vectors of change.

Holt, Jason; Schrum, Corinna; Cannaby, Heather; Allen, Icarus; Artioli, Yuri; Butenschon, Momme; Daewel, Ute; Fach, Bettina; Pushpadas, Dhanya; Salihoglu, Baris; Wakelin, Sarah

2013-04-01

184

Predicting Weather  

NSDL National Science Digital Library

By performing the activities presented in this website, fourth grade students can learn about weather instruments and data collection. This website, produced by the Government of Saskatchewan, also explores how the weather can impact local communities. Each activity presented here includes both objectives and assessment techniques for the lesson. Sixteen different activity suggestions provide students and teachers with ample opportunities to explore weather in the classroom.

2008-03-28

185

Weather Experiments  

NSDL National Science Digital Library

Looking for fun ways to learn about weather? Weather Wiz Kids has 39 fun weather related experiments for you to try. These experiments can be done in the classroom with your friends or even at home! Some of the experiments on the site include: tornado in a bottle, make lightning, make it rain, cloud in a bottle, what's in the wind, the Doppler Effect, and baking soda volcano.

2010-01-01

186

Weather Instruments  

NSDL National Science Digital Library

This Topic in Depth discusses the variety of instruments used to collect climate and weather data. The first two websites provide simple introductions to the many weather instruments. Bethune Academy's Weather Center (1) discusses the functions of psychrometers, anemometers, weather balloons, thermometers, and barometers. The Illinois State Water Survey (2) furnishes many images of various instruments that collect data daily for legal issues, farmers, educators, students, and researchers. The third website (3), created by the Center for Improving Engineering and Science Education (CIESE), provides a classroom activity to educate users on how to build and use weather instruments. By the end of the group project, students should know all about wind vanes, rain gauges, anemometers, and thermometers. Next, the Miami Museum of Science provides a variety of activities to help students learn about the many weather instruments including wind scales and wind chimes (4). Students can learn about the wind, air pressure, moisture, and temperature. At the fifth website, the Tyson Research Center at Washington University describes the devices it uses in its research (5). At the various links, users can find out the center's many projects that utilize meteorological data such as acid rain monitoring. The sixth website, a pdf document created by Dr. John Guyton at the Mississippi State University Extension Service, provides guidance to teachers about the education of weather patterns and instruments (6). Users can find helpful information on pressure systems, humidity, cloud patterns, and much more. Next, the University of Richmond discusses the tools meteorologists use to learn about the weather (7). While providing materials about the basic tools discussed in the other websites, this site also offers information about weather satellites, radar, and computer models. After discovering the many weather instruments, users can learn about weather data output and analysis at the Next Generation Weather Lab website (8). This expansive website provides an abundance of surface data and upper air data as well as satellite and radar images for the United States.

187

DOE Workshop; Pan-Gass Conference on the Representation of Atmospheric Processes in Weather and Climate Models  

SciTech Connect

This is the first meeting of the whole new GEWEX (Global Energy and Water Cycle Experiment) Atmospheric System Study (GASS) project that has been formed from the merger of the GEWEX Cloud System Study (GCSS) Project and the GEWEX Atmospheric Boundary Layer Studies (GABLS). As such, this meeting will play a major role in energizing GEWEX work in the area of atmospheric parameterizations of clouds, convection, stable boundary layers, and aerosol-cloud interactions for the numerical models used for weather and climate projections at both global and regional scales. The representation of these processes in models is crucial to GEWEX goals of improved prediction of the energy and water cycles at both weather and climate timescales. This proposal seeks funds to be used to cover incidental and travel expenses for U.S.-based graduate students and early career scientists (i.e., within 5 years of receiving their highest degree). We anticipate using DOE funding to support 5-10 people. We will advertise the availability of these funds by providing a box to check for interested participants on the online workshop registration form. We will also send a note to our participants' mailing lists reminding them that the funds are available and asking senior scientists to encourage their more junior colleagues to participate. All meeting participants are encouraged to submit abstracts for oral or poster presentations. The science organizing committee (see below) will base funding decisions on the relevance and quality of these abstracts, with preference given to under-represented populations (especially women and minorities) and to early career scientists being actively mentored at the meeting (e.g. students or postdocs attending the meeting with their advisor).

Morrison, PI Hugh

2012-09-21

188

NATURAL ARSENIC CONTAMINATION OF HOLOCENE ALLUVIAL AQUIFERS BY LINKED TECTONIC, WEATHERING, AND MICROBIAL PROCESSES  

EPA Science Inventory

Linked tectonic, geochemical, and biologic processes lead to natural arsenic contamination of groundwater in Holocene alluvial aquifers, which are the main threat to human health around the world. These groundwaters are commonly found a long distance from their ultimate source of...

189

Extrapolation of space weathering processes to other small solar system bodies  

NASA Technical Reports Server (NTRS)

A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

Gaffey, M. J.

1993-01-01

190

Process Physics: From Quantum Foam to General Relativity  

E-print Network

Progress in the new information-theoretic process physics is reported in which the link to the phenomenology of general relativity is made. In process physics the fundamental assumption is that reality is to be modelled as self-organising semantic (or internal or relational) information using a self-referentially limited neural network model. Previous progress in process physics included the demonstration that space and quantum physics are emergent and unified, with time a distinct non-geometric process, that quantum phenomena are caused by fractal topological defects embedded in and forming a growing three-dimensional fractal process-space, which is essentially a quantum foam. Other features of the emergent physics were: quantum field theory with emergent flavour and confined colour, limited causality and the Born quantum measurement metarule, inertia, time-dilation effects, gravity and the equivalence principle, a growing universe with a cosmological constant, black holes and event horizons, and the emergence of classicality. Here general relativity and the technical language of general covariance is seen not to be fundamental but a phenomenological construct, arising as an amalgam of two distinct phenomena: the `gravitational' characteristics of the emergent quantum foam for which `matter' acts as a sink, and the classical `spacetime' measurement protocol, but with the later violated by quantum measurement processes. Quantum gravity, as manifested in the emergent Quantum Homotopic Field Theory of the process-space or quantum foam, is logically prior to the emergence of the general relativity phenomenology, and cannot be derived from it.

Reginald T. Cahill

2002-03-05

191

Water quality mapping and assessment, and weathering processes of selected aflaj in Oman  

Microsoft Academic Search

There are more than 4,000 falaj (singular of a peculiar dug channel) distributed in different regions in Oman. The chemical\\u000a characteristics of the water in 42 falaj were studied to evaluate the major ion chemistry; geochemical processes controlling\\u000a water composition; and suitability of water for drinking, domestic, and irrigation uses. GIS-based maps indicate that the\\u000a spatial distribution of chemical properties

Habes Ahmad Ghrefat; Ahmad Jamarh; Ahmed Al-Futaisi; Badr Al-Abri

192

Observe the effects of mechanical weathering  

NSDL National Science Digital Library

In this interactive Earth science resource, students are first presented with six photographs, each featuring a different mechanical weathering event in which rock is broken down. Examples of the events include road damage due to ice heaving and the expansion of cracks in rocks due to tree growth. Students are instructed to click on each labeled image to see an enlarged version of it. In the enlarged view, brief text, often accompanied by visual cues such as arrows, explains the physical weathering process shown. Copyright 2005 Eisenhower National Clearinghouse

Education, Terc. C.; Littell, Mcdougal

2003-01-01

193

Mesoscale severe weather development under orographic influences  

NASA Astrophysics Data System (ADS)

Overall goals of this 3-year study are to: 1)examine the role of topography in the development of convective systems and 2) assess the orographic influences on cold season severe weather, such as blizzards, lee cyclogenesis, etc. Four approaches were taken to attain these goals: 1)Implementation of a field measurement program, 2) diagnostic studies of energy fluxes during various seasons, 3) numerical simulation of severe weather development, and 4) evaluation of model sensitivity ot various physical processes. Progress has been made on all four of these fronts in the first year.

Reiter, Elmar R.; Bresch, James F.; Klitch, Marjorie A.; MacDonald, Bruce C.; Sheaffer, John D.

1986-07-01

194

Using Forecasting to Teach Weather Science  

NASA Astrophysics Data System (ADS)

Weather affects our lives and hence, is a popular topic in daily conversations and in the media. Therefore, it is not only important to teach weather, but is also a good idea to use 'weather' as a topic in science teaching. Science education has two main objectives: to acquire scientific concepts and methods. Weather forecasting is an adequate theme to teach scientific methods because it is dependent on observation. However, it is not easy to forecast weather using only temporal observation. We need to know the tendency of 'weather change' via consecutive and/or continuous weather observation. Students will acquire scientific-observation skills through weather observation. Data-processing skills would be enhanced through a weather-forecasting contest. A contest should be announced within 5 days of school events, such as a school excursion and field day. Students submit their own weather forecast by gathering weather information through the internet, news paper and so on. A weather-forecasting contest compels the student to observe the weather more often. We currently have some different weather forecasts. For example, American weather-related companies such as ACCU weather and Weather Channel provide weather forecast for the many locations all over the world. Comparing these weather forecasting with actual weather, participants such as students could evaluate the differences between forecasted and actual temperatures. Participants will judge the best weather forecast based on the magnitude of the difference. Also, participants evaluate the 'hitting ratio' of each weather forecast. Students can learn elementary statistics by comparing various weather forecasts. We have developed our weather web-site that provides our own weather forecasting and observation. Students acquire science skills using our weather web-site. We will report our lessen plans and explain our weather web-site.

Tsubota, Y.; Takahashi, T.

2009-09-01

195

Analysis of weather patterns associated with air quality degradation and potential health impacts  

EPA Science Inventory

Emissions from anthropogenic and natural sources into the atmosphere are determined in large measure by prevailing weather conditions through complex physical, dynamical and chemical processes. Air pollution episodes are characterized by degradation in air quality as reflected by...

196

Ontology of physics for biology: representing physical dependencies as a basis for biological processes  

PubMed Central

Background In prior work, we presented the Ontology of Physics for Biology (OPB) as a computational ontology for use in the annotation and representations of biophysical knowledge encoded in repositories of physics-based biosimulation models. We introduced OPB:Physical entity and OPB:Physical property classes that extend available spatiotemporal representations of physical entities and processes to explicitly represent the thermodynamics and dynamics of physiological processes. Our utilitarian, long-term aim is to develop computational tools for creating and querying formalized physiological knowledge for use by multiscale “physiome” projects such as the EU’s Virtual Physiological Human (VPH) and NIH’s Virtual Physiological Rat (VPR). Results Here we describe the OPB:Physical dependency taxonomy of classes that represent of the laws of classical physics that are the “rules” by which physical properties of physical entities change during occurrences of physical processes. For example, the fluid analog of Ohm’s law (as for electric currents) is used to describe how a blood flow rate depends on a blood pressure gradient. Hooke’s law (as in elastic deformations of springs) is used to describe how an increase in vascular volume increases blood pressure. We classify such dependencies according to the flow, transformation, and storage of thermodynamic energy that occurs during processes governed by the dependencies. Conclusions We have developed the OPB and annotation methods to represent the meaning—the biophysical semantics—of the mathematical statements of physiological analysis and the biophysical content of models and datasets. Here we describe and discuss our approach to an ontological representation of physical laws (as dependencies) and properties as encoded for the mathematical analysis of biophysical processes. PMID:24295137

2013-01-01

197

Space Weathering of Lunar Rocks  

NASA Technical Reports Server (NTRS)

All materials exposed at the lunar surface undergo space weathering processes. On the Moon, boulders make up only a small percentage of the exposed surface, and areas where such rocks are exposed, like central peaks, are often among the least space weathered regions identified from remote sensing data. Yet space weathered surfaces (patina) are relatively common on returned rock samples, some of which directly sample the surface of larger boulders. Because, as witness plates to lunar space weathering, rocks and boulders experience longer exposure times compared to lunar soil grains, they allow us to develop a deeper perspective on the relative importance of various weathering processes as a function of time.

Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

2012-01-01

198

Genesis of karren in Kentucky Lake, Tennessee: Interaction of geologic structure, weathering processes, and bioerosion  

SciTech Connect

While karst features formed along marine coastlines are commonly reported, shoreline karst features produced within lacustrine systems have received little attention. The shoreline of Bond Island'' in Kentucky Lake has evolved a distinctive karren geomorphology not recognized elsewhere in the lake. The karren consist of well-developed clint and grike topography, trench formation, solution pits, flutes, and runnels, and pit and tunnel development. Two processes are responsible for the karren. First, freshwater dissolution and wave action on structurally fractured Decatur Limestone (Silurian) mechanically and chemically weaken the entire exposed surface. Second, a seasonal cycle of winter freeze-thaw and frost wedging followed by spring bioerosion overprints the first set of processes. Bioerosion by chemical dissolution involving a complex association of predominantly chironomids, algae, fungi, and bryozoa results in preferential dissolution along joints, stylolites, and bedding planes to form shallow spindle-shaped solution pits over the entire surface and sides of the karren. The solution pits average 1 cm length by 0.4 cm depth densely covering rock surfaces. This study suggests that seasonal bioerosion may constitute a more important geomorphic factor in lacustrine systems than previously recognized.

Gibson, M.A.; Smith, W.L. (Univ. of Tennessee, Martin, TN (United States))

1993-03-01

199

Zeolite Formation and Weathering Processes Within the Martian Regolith: An Antarctic Analog  

NASA Technical Reports Server (NTRS)

As more information is obtained about the nature of the surface compositions and processes operating on Mars, it is clear that significant erosional and depositional features are present on the surface. Apparent aqueous or other fluid activity on Mars has produced many of the erosional and outflow features observed. Evidence of aqueous activity on Mars has been reported by earlier studies. Gooding and colleagues championed the cause of pre-terrestrial aqueous alteration processes recorded in Martian meteorites. Oxygen isotope studies on Martian meteorites by Karlsson et al. and Romenek et al. gave evidence for two separate water reservoirs on Mars. The oxygen isotopic compositions of the host silicate minerals was different from the oxygen isotopic composition of the secondary alteration products within the SNC meteorites. This implied that the oxygen associated with fluids which produced the secondary alteration was from volatiles which were possibly added to the planetary inventory after formation of the primary silicates from which the SNC s were formed. The source of the oxygen may have been from a cometary or volatile-rich veneer added to the planet in its first 600 million years.

Gibson, E. K.; McKay, D. S.; Wentworth, S. J.; Socki, R. A.

2003-01-01

200

A model of weathering intensity for the Australian continent  

NASA Astrophysics Data System (ADS)

Regolith encompasses all weathered materials in the zone between the Earth's surface and fresh bedrock at depth. This weathered zone includes the soil, which may constitute the whole of the regolith profile or represent only its upper part. Important hydrological and biogeochemical processes operate within the regolith, including the infiltration and storage of near-surface water and nutrients, which sustain agricultural productivity. The degree to which the regolith is weathered (or its weathering intensity) is intrinsically linked to the factors involved in soil formation including parent material, climate, topography, biota and time. The degree to which the bedrock or sediments are weathered has a significant effect on the nature and distribution of regolith materials. There is commonly a strong correlation between weathering intensity and the degree of soil development as well as the depth of the weathering front. Changes in weathering intensity correspond to changes in the geochemical and physical properties of bedrock, ranging from essentially unweathered parent materials through to intensely weathered and leached regolith where all traits of the original protolith (original unweathered rock) are overprinted or lost altogether. With increasing weathering intensity we see mineral and geochemical convergence to more resistant secondary weathered materials including clay, silica, and various oxides. A weathering intensity index (WII) over the Australian continent has been developed at a 100 m resolution using two regression models based on airborne gamma-ray spectrometry imagery and the Shuttle Radar Topography Mission (SRTM) elevation data. Airborne gamma-ray spectrometry measures the concentration of three radioelements -- potassium (K), thorium (Th) and uranium (U) at the Earth's surface. The total gamma-ray flux (dose) is also calculated based on the weighted additions of the three radioelements. In general K is leached with increasing weathering whereas Th and U typically show increases due to their association in clays and oxides in the profile. These geochemical relationships underpin the first model prediction. In the case where no gamma-ray data is available or where the bedrock is very low in radioelements (e.g. basalt, quartz-rich sandstone) surface relief is used as surrogate in the second prediction model. The two models are combined to generate a weathering intensity index of the Australian continent. The weathering intensity index has been developed for erosional landscapes but also provides useful information on deposition processes and materials. The weathering intensity prediction is evaluated with surface geochemistry (compared with geochemical indices) and previous regolith-landform mapping. The use of the weathering intensity index in natural resource management and mineral exploration is discussed.

Wilford, J.

2013-12-01

201

Weather Forecasting  

NSDL National Science Digital Library

This activity (on page 2 of the PDF) is a full inquiry investigation into meteorology and forecasting. Learners will research weather folklore, specifically looking for old-fashioned ways of predicting the weather. Then, they'll record observations of these predictors along with readings from their own homemade barometer, graphing the correct predictions for analysis. Relates to linked video, DragonflyTV: Forecasting.

Twin Cities Public Television, Inc.

2005-01-01

202

Space Weather  

E-print Network

Space Weather :: Printer Friendly Version of Article 2004SW000119 http://www.agu magnetic Faraday cages, to designing artificial magnetospheres around the spacecraft, to employing into nature. Louis J. Lanzerotti is Editor of Space Weather, Distinguished Research Professor at the New

Shepherd, Simon

203

Wacky Weather  

ERIC Educational Resources Information Center

What do a leaf blower, water hose, fan, and ice cubes have in common? Ask the students who participated in an integrative science, technology, engineering, and mathematics (I-STEM) education unit, "Wacky Weather," and they will tell say "fun and severe weather"--words one might not have expected! The purpose of the unit…

Sabarre, Amy; Gulino, Jacqueline

2013-01-01

204

JOINT DRY/WET WEATHER TREATMENT OF MUNICIPAL WASTEWATER AT CLATSKANIE, OREGON  

EPA Science Inventory

This report describes the two year plant scale evaluation of physical and biological processes used for joint treatment of dry weather and storm generated sanitary sewer flow. The project was conducted in Clatskanie, OR at the City's new joint dry/wet weather sewage treatment pla...

205

The emergence of the physical world from information processing  

E-print Network

This paper links the conjecture that the physical world is a virtual reality to the findings of modern physics. What is usually the subject of science fiction is here proposed as a scientific theory open to empirical evaluation. We know from physics how the world behaves, and from computing how information behaves, so whether the physical world arises from ongoing information processing is a question science can evaluate. A prima facie case for the virtual reality conjecture is presented. If a photon is a pixel on a multi-dimensional grid that gives rise to space, the speed of light could reflect its refresh rate. If mass, charge and energy all arise from processing, the many conservation laws of physics could reduce to a single law of dynamic information conservation. If the universe is a virtual reality, then its big bang creation could be simply when the system was booted up. Deriving core physics from information processing could reconcile relativity and quantum theory, with the former how processing crea...

Whitworth, B

2010-01-01

206

Hydrologic regulation of chemical weathering and the geologic carbon cycle.  

PubMed

Earth's temperature is thought to be regulated by a negative feedback between atmospheric CO2 levels and chemical weathering of silicate rocks that operates over million-year time scales. To explain variations in the strength of the weathering feedback, we present a model for silicate weathering that regulates climatic and tectonic forcing through hydrologic processes and imposes a thermodynamic limit on weathering fluxes, based on the physical and chemical properties of river basins. Climate regulation by silicate weathering is thus strongest when global topography is elevated, similar to the situation today, and lowest when global topography is more subdued, allowing planetary temperatures to vary depending on the global distribution of topography and mountain belts, even in the absence of appreciable changes in CO2 degassing rates. PMID:24625927

Maher, K; Chamberlain, C P

2014-03-28

207

The 2007 Space Weather Workshop  

NASA Astrophysics Data System (ADS)

The applications of space weather information are changing rapidly. New operating procedures at electric power facilities now take geomagnetic activity into account; the next-generation air transportation system could rely heavily on GPS navigation, which is susceptible to ionospheric disturbances; and satellite design, operation, and human space flight all demand accurate specification and prediction of space radiation. Our ability to meet these needs is improving. Our increased knowledge of the underlying physical processes in the solar-terrestrial environment, our improving numerical models, and new targeted data sources are enhancing our ability to specify and predict the important conditions in space.

Onsager, Terrance; Zwickl, Ron

2007-02-01

208

Planetary Weather  

NSDL National Science Digital Library

This lesson plan is part of the DiscoverySchool.com lesson plan library for grades 6-8. It focuses on the weather conditions on other planets. After learning more about weather patterns, students research the weather on a given planet and create a visual display of the conditions there. It includes objectives, materials, procedures, discussion questions, evaluation ideas, suggested readings, and vocabulary. There are videos available to order which complement this lesson, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

209

Weathering and Erosion  

NSDL National Science Digital Library

In this multi-station lab, learners conduct a series of experiments to explore the processes and effects of weathering and erosion. Using the results from these explorations, learners design and conduct an experiment comparing the rate of erosion in different biomes. Use this activity to teach weathering and erosion, and also to illustrate how scientists often use the results of one experiment to inspire another. This activity is intended to be conducted over multiple meetings.

Whitfield, Lise

2010-01-01

210

Comparison between physical variables acquired by a new multiparametric platform, ELFO, and data calculated by a three-dimensional hydrodynamic model in different weather conditions at Tiber River mouth (Latium coast, Italy)  

NASA Astrophysics Data System (ADS)

The coastal ecosystem is characterized by high variability physical processes, which are strongly influenced by sudden changes in weather conditions. For this reason instruments able to collect data in a short time or mathematical models able to simulate the same phenomena from experimental data are basic. In this study in situ data are compared with data calculated by three-dimensional hydrodynamic model. The multiparametric platform was developed ad hoc by Laboratory of Experimental Oceanology and Marine Ecology (DECOS, Tuscia University) for coastal monitoring by small vessels (ELFO), and integrates temperature, conductivity, dissolved oxygen and suspended solids measures with bio-optical measures like fluorescence, photosynthetic efficiency and PAR. The hydrodynamic model is the three-dimensional coastal hydrodynamic DELFT3D-FLOW simulating processes of temperature and salinity diffusion and the transport of suspended sediment (cohesive and non cohesive) in the water column. This study analyses the area at mouth of Tiber river investigated by two surveys wiht different weather conditions. Data collected during the first survey were used to calibrate the DELFT3D-FLOW model which computational domain extends from the Argentario headland to Capo Anzio. A microscale wind field (resolution of about 7 km), provided by the atmospheric model COSMO-ME (developed by CNMCA of Aeronautica Militare, Italy), was used to reproduce the hydrodynamic field and the distribution of the physical variables of the whole period. In this way the data calculated by the model can be compared with those collected in situ during the second survey. Moreover dynamic phenomena existed between the two monitoring periods can be investigated.

Bonamano, Simone; Piermattei, Viviana; Marcelli, Marco; Peviani, Maximo

2010-05-01

211

Weatherizing America  

ScienceCinema

As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony;

2013-05-29

212

Weather One  

NSDL National Science Digital Library

This website contains summaries and lessons about various aspects of weather. This includes the seasons, types of clouds, air, winds, global warming, hurricanes, tornadoes and lightning. Worksheets are provided to accompany the lesson themes.

Friend, Duane

213

Winter Weather  

MedlinePLUS

... During a Wildfire Responders Wildfire Smoke After a Fire Worker Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather Extreme ... at Disaster Sites Preventing Chain Saw Injuries During Tree Removal Electrical Safety and Generators Handling Human Remains ...

214

Weather Creator  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What can you do to make it rain or even snow? 4. Does it always snow when ...

Kshumway

2009-09-28

215

Exploring Weather  

NSDL National Science Digital Library

Second Grade Standard 3: Students will develop an understanding of their environment. Objective 2: Observe and describe weather. Indicator a: Observe and describe patterns of change in weather. Monday, February 1st: Look at the five-day forecast for Salt Lake City, Utah at Five day forecasts. The high temperature for the day will be in red and the low temperature will be in blue. Make sure you look at the temperature listed in degrees Farenheit (F) not degrees Celcius (C). Make ...

Emily, Miss

2010-01-29

216

Weather Maps  

NSDL National Science Digital Library

This lesson plan is part of the DiscoverySchool.com lesson plan library for grades K-5. It focuses on basic information about the weather and how different weather maps depict conditions. Included are objectives, materials, procedures, discussion questions, evaluation ideas, suggested readings, and vocabulary. There are videos available to order which complement this lesson, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

217

Rainy Weather Science.  

ERIC Educational Resources Information Center

Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and…

Reynolds, Karen

1996-01-01

218

Space Weather Basics, 2nd Edition  

NSDL National Science Digital Library

This module presents an overview of space weather processes, their impacts on Earth and human activities, and the technologies used for forecasting space weather events. The module goal is to provide NWS forecasters a basic understanding of space weather and the operations of NOAA's Space Weather Prediction Center (SWPC). It will be of interest to a general audience as well.

Comet

2012-01-11

219

Physical Processes in the Far and Near Space  

E-print Network

The book examines some of the questions of modern cosmology, the physics of atmospheric phenomena, the physics of quasi-particles and atomic nuclei in the Universe. It consists of three parts, each discusses the theoretical problems of various subjects of cosmic physics. The first part examines the physics of the expanding Universe, with emphasis on the content of the latest revolution in cosmology. It is today well established that the universe is dominated by a vacuum that exceeds the density of baryonic forms of cosmic matter, that the dynamics of the cosmic expansion controls the vacuum antigravity and, finally, that the cosmological expansion is accelerating. In the second part we investigate the processes leading to the electrization of gas fluxes in the solar atmosphere and the generation of neutrons in the active regions of its atmosphere, issues of electrization of thunderstorm clouds in the troposphere of the Earth, the formation and development of noctilucent clouds in the area of the mesosphere. I...

B., Dubovichenko S; M, Chechin L

2010-01-01

220

Effective Physical Processes and Active Information in Quantum Computing  

E-print Network

The recent debate on hypercomputation has arisen new questions both on the computational abilities of quantum systems and the Church-Turing Thesis role in Physics. We propose here the idea of "effective physical process" as the essentially physical notion of computation. By using the Bohm and Hiley active information concept we analyze the differences between the standard form (quantum gates) and the non-standard one (adiabatic and morphogenetic) of Quantum Computing, and we point out how its Super-Turing potentialities derive from an incomputable information source in accordance with Bell's constraints. On condition that we give up the formal concept of "universality", the possibility to realize quantum oracles is reachable. In this way computation is led back to the logic of physical world.

Ignazio Licata

2007-05-08

221

Calibrating DOE-2 to Weather and Non-Weather-Dependent Loads for a Commercial Building: Data Processing Routines to Calibrate a DOE-2 Model, Volume II  

E-print Network

into LOTUS which, together with the 3DGRAPHIC Add-In package and a LOTUS instruction macro, generates the four *.PIC files that create the plot. Data Processing Routines to Calibrate a DOE-2 Model (C) Copyright 1992 Texas Engineering Experiment Station Beta... and the monitored and predicted whole-building electrical load data files are then transferred to the PC. A batch file, 3DGRAPH.BAT (Flag A.13), processes each graph data file into a 3D graph using the COLROW3D program and the LOTUS spreadsheet package...

Bronson, J. D.

1992-01-01

222

Radiative Processes and Mass Renormalization in Plasma Physics Theory  

Microsoft Academic Search

The present paper contains a review concerning the radiative effects in plasma physics and radiative corrections to the quasilinear equation, which describes the particle heating and acceleration. A new equation for radiative collision integral is derived. A review is also presented on the investigations of new processes of nonlinear absorption and amplification of waves in plasma related to the radiative

V N Tsytovich

1982-01-01

223

Radiative processes and mass renormalization in plasma physics theory  

Microsoft Academic Search

The present paper contains a review concerning the radiative effects in plasma physics and radiative corrections to the quasilinear equation, which describes the particle heating and acceleration. A new equation for radiative collision integral is derived. A review is also presented on the investigations of new processes of nonlinear absorption and amplification of waves in plasma related to the radiative

V. N. Tsytovich

1982-01-01

224

Quantum Information Processing with NMR MIT Department of Physics  

E-print Network

Quantum Information Processing with NMR MIT Department of Physics (Dated: August 26, 2010) This experiment will let you perform a series of simple quantum computations on a two spin system, demonstrating one and two quantum-bit quantum logic gates, and a circuit implementing the Deutsch-Jozsa quantum

Seager, Sara

225

Determination of the physical processes underlying observed slab dynamics  

Microsoft Academic Search

Comparison of slab dynamics from 2D numerical models to a suite of observations has allowed us to determine the physical processes underlying the observed correlations between slab dip, buoyancy, and convergence ki- nematics. We find that stiff slabs, with viscosity 5-6 orders of magnitude greater than the asthenosphere, experi - ence three stages of evolution. Initially the slab is stiff

G. Hirth; P. Kelemen; M. Billen

226

A physical storage model for efficient statistical query processing  

Microsoft Academic Search

A common approach to improving the performance of statistical query processing is to use precomputed results. Another lower-level approach would be to redesign the storage structure for statistical databases. This avenue is relatively unexplored. The objective of this paper is to present a physical storage structure for statistical databases, whose design is motivated by the characteristics of statistical queries. We

W. K. Ng; C. V. Ravishankar

1994-01-01

227

Physical processes during development of upward leaders from tall structures  

Microsoft Academic Search

The objective of our study was to identify and interpret the various processes during development of upward positive leaders from tall structures. We provide a physical interpretation for the varying luminosity of the leader channel during its initial ascent and the pulsing luminosity during much later stages of the established leader. Our analysis confirms that pulsed luminosity is a result

Vladislav Mazur; Lothar H. Ruhnke

2011-01-01

228

Field Observations of Weathering and Mass Wasting  

NSDL National Science Digital Library

This activity requires students to locate local examples of physical and chemical weathering, as well mass wasting, for which they must identify the type of process involved and describe the resulting effects on landform development. The students must write up their observations in a brief, written report using a technical writing style, which must include labeled photographs and sketches that support their observations and descriptions.

Davis, Lisa

229

Challenges in Teaching Space Physics to Different Target Groups From Space Weather Forecasters to Heavy-weight Theorists  

NASA Astrophysics Data System (ADS)

Plasma physics as the backbone of space physics is difficult and thus the space physics students need to have strong foundations in general physics, in particular in classical electrodynamics and thermodynamics, and master the basic mathematical tools for physicists. In many universities the number of students specializing in space physics at Master's and Doctoral levels is rather small and the students may have quite different preferences ranging from experimental approach to hard-core space plasma theory. This poses challenges in building up a study program that has both the variety and depth needed to motivate the best students to choose this field. At the University of Helsinki we require all beginning space physics students, regardless whether they enter the field as Master's or Doctoral degree students, to take a one-semester package consisting of plasma physics and its space applications. However, some compromises are necessary. For example, it is not at all clear, how thoroughly Landau damping should be taught at the first run or how deeply should the intricacies of collisionless reconnection be discussed. In both cases we have left the details to an optional course in advanced space physics, even with the risk that the student's appreciation of, e.g., reconnection may remain at the level of a magic wand. For learning experimental work, data analysis or computer simulations we have actively pursued arrangements for the Master's degree students to get a summer employments in active research groups, which usually lead to the Master's theses. All doctoral students are members of research groups and participate in experimental work, data analysis, simulation studies or theory development, or any combination of these. We emphasize strongly "learning by doing" all the way from the weekly home exercises during the lecture courses to the PhD theses which in Finland consist typically of 4-6 peer-reviewed articles with a comprehensive introductory part.

Koskinen, H. E.

2008-12-01

230

The Sun and Space Weather  

NASA Astrophysics Data System (ADS)

This second edition is a great enhancement of literature which will help the reader get deeper into the specific topics. There are new sections included such as space weather data sources and examples, new satellite missions, and the latest results. At the end a comprehensive index is given which will allow the reader to quickly find his topics of interest. The Sun and Space weather are two rapidly evolving topics. The importance of the Sun for the Earth, life on Earth, climate and weather processes was recognized long ago by the ancients. Now, for the first time there is a continuous surveillance of solar activity at nearly all wavelengths. These data can be used to improve our understanding of the complex Sun-Earth interaction. The first chapters of the book deal with the Sun as a star and its activity phenomena as well as its activity cycle in order to understand the complex physics of the Sun-Earth system. The reader will see that there are many phenomena but still no definite explanations and models exist for many of them. Other topics are the influences on the Earth's atmosphere, long and short term climate variations. The last chapters discuss the protection against enhanced radiation environment in view of upcoming manned missions to the Moon and Mars, and the threat from space debris, asteroids and meteoroids. Since the field is quite interdisciplinary, the book will be of interest to scientists working in different fields such as solar physics, geophysics, and space physics. Link: http://www.springer.com/west/home/generic/search/results?SGWID=4-40109-22-173699408-0

Hanslmeier, Arnold

2007-06-01

231

Soil Heat Flow. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.  

ERIC Educational Resources Information Center

These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Soil heat flow and the resulting soil temperature distributions have ecological consequences…

Simpson, James R.

232

Biological Production in Lakes. Physical Processes in Terrestrial and Aquatic Ecosystems, Ecological Processes.  

ERIC Educational Resources Information Center

These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Primary production in aquatic ecosystems is carried out by phytoplankton, microscopic plants…

Walters, R. A.; Carey, G. F.

233

Pressure and Buoyancy in Aquatic Ecosystems. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.  

ERIC Educational Resources Information Center

This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module explores some of the characteristics of aquatic organisms which can be…

Cowan, Christina E.

234

Fluid Dynamics Applied to Streams. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.  

ERIC Educational Resources Information Center

This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module deals specifically with concepts that are basic to fluid flow and…

Cowan, Christina E.

235

Physics-based model for electro-chemical process  

SciTech Connect

Considering the kinetics of electrochemical reactions and mass transfer at the surface and near-surface of the electrode, a physics-based separation model for separating actinides from fission products in an electro-refiner is developed. The model, taking into account the physical, chemical and electrochemical processes at the electrode surface, can be applied to study electrorefining kinetics. One of the methods used for validation has been to apply the developed model to the computation of the cyclic voltammetry process of PuCl{sub 3} and UCl{sub 3} at a solid electrode in molten KCl-LiCl. The computed results appear to be similar to experimental measures. The separation model can be applied to predict materials flows under normal and abnormal operation conditions. Parametric studies can be conducted based on the model to identify the most important factors that affect the electrorefining processes.

Zhang, Jinsuo [The Ohio State University, 201 W19th Avenue, Columbus, OH 43210 (United States)

2013-07-01

236

Delicious Differential Weathering  

NSDL National Science Digital Library

Students are asked to place a Baby Ruth candy bar in their mouths but are asked not to bite it. Once they have sucked off all the chocolate and caramel the students are given permission to bite the peanuts. After lecturing on the differences between chemical and physical weathering students are asked to list the order of ingredients they tasted. Each group is given a sample of granite. Students are asked to list three visible minerals in the granite. Relate the minerals of the granite (hornblende, feldspar, and quartz) to the ingredients of the candy bar. Explain Bowen's reaction series and how different minerals will weather first and how climate will affect weathering rates.

Gorte, Mary

237

Weather Forecasting  

NSDL National Science Digital Library

Weather Forecasting is one of several online guides produced by the Weather World 2010 project at the University of Illinois. These guides use multimedia technology and the dynamic capabilities of the web to incorporate text, colorful diagrams, animations, computer simulations, audio, and video to introduce topics and concepts in the atmospheric sciences. This module introduces forecast methods and the numerous factors one must consider when attempting to make an accurate forecast. Sections include forecasting methods for different scenarios, surface features affecting forecasting, forecasting temperatures for day and night, and factors for forecasting precipitation.

2010-01-01

238

Wild Weather  

NSDL National Science Digital Library

In this online, interactive module, students learn about severe weather (thunderstorms, hurricanes, tornadoes, and blizzards) and the key features for each type of "wild weather" using satellite images. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

239

Wonderful Weather  

NSDL National Science Digital Library

Second Grade Standard 3: Students will develop an understanding of their environment. Objective 2: Observe and describe weather. Indicator a: Observe and describe patterns of change in weather. Monday November 6th: Look at the five-day forecast for Logan Utah at Five Day Forecast in Utah. The high temperature for the day will be in red and the low temperature will be in blue. Look at the temperature listed in degrees Farenheit (F) not degrees Celcius (C). Make a bar graph for the ...

Broadhead, Ms.

2007-11-06

240

Space Weather  

NSDL National Science Digital Library

With three levels to choose from on each page - beginner, intermediate or advanced - this site provides information on Space Weather and the terms scientists use to describe the everchanging conditions in space. Explosions on the Sun create storms of radiation, fluctuating magnetic fields, and swarms of energetic particles. These phenomena travel outward through the Solar System with the solar wind. Upon arrival at Earth, they interact in complex ways with Earth's magnetic field, creating Earth's radiation belts and the Aurora. Some space weather storms can damage satellites, disable electric power grids, and disrupt cell phone communications systems. This site provides images, activities, and interesting facts about all of these events.

2004-02-06

241

Unisys Weather  

NSDL National Science Digital Library

The Unisys weather website offers a host of weather analyses and forecasts. In the Analyses link, visitors can find satellite images as well as surface, upper air, and radar images. Visitors can learn the intricacies of Unisys's many forecast models such as the Nested Grid Model (NGM), Aviation Model, and the Rapid Update Cycle (RUC) Model. Users can find archived hurricane data for the Atlantic, the Eastern Pacific, and the Western Pacific. The site also furnishes archived surface maps, infrared satellite images, upper air charts, and sea surface temperature (SST) plots.

242

Assessing processes in uncertain, complex physical phenomena and manufacturing  

SciTech Connect

PREDICT (Performance and Reliability Evaluation with Diverse Information Combination and Tracking) is a set of structured quantitative approaches for the evaluation of system performance based on multiple information sources. The methodology integrates diverse types and sources of information, and their associated uncertainties, to develop full distributions for performance metrics, such as reliability. The successful application of PREDICT has involved system performance assessment in automotive product development, aging nuclear weapons, and fatigued turbine jet engines. In each of these applications, complex physical, mechanical and materials processes affect performance, safety and reliability assessments. Processes also include the physical actions taken during manufacturing, quality control, inspections, assembly, etc. and the steps involved in product design, development and certification. In this paper, we will examine the various types of processes involved in the decision making leading to production in an automotive system reliability example. Analysis of these processes includes not only understanding their impact on performance and reliability, but also the uncertainties associated with them. The automotive example demonstrates some of the tools used in tackling the complex problem of understanding processes. While some tools and methods exist for understanding processes (man made and natural) and the uncertainties associated with them, many of the complex issues discussed are open for continued research efforts.

Booker, J. M. (Jane M.); Kerscher, W. J. III (William J.); Smith, R. E. (Ronald E.)

2002-01-01

243

Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.  

PubMed

Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus. PMID:24501145

Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

2014-02-01

244

TESTING SOLIDS SETTING APPARATUSES FOR DESIGN AND OPERATION OF WET-WEATHER FLOW SOLIDS-LIQUID SEPARATION PROCESSES  

EPA Science Inventory

This study was a side-by-side comparison of two settling evaluation methods: one traditional and one new. The project investigated whether these column tests were capable of capturing or representing the rapidly settling particles present in wet-weather flows (WWF). The report r...

245

57 Fe Mössbauer spectroscopy studies of chondritic meteorites from the Atacama Desert, Chile: Implications for weathering processes  

NASA Astrophysics Data System (ADS)

Some terrestrial areas have climatic and geomorphologic features that favor the preservation, and therefore, accumulation of meteorites. The Atacama Desert in Chile is among the most important of such areas, known as dense collection areas. This desert is the driest on Earth, one of the most arid, uninhabitable locals with semi-arid, arid and hyper-arid conditions. The meteorites studied here were collected from within the dense collection area of San Juan at the Central Depression and Coastal Range of Atacama Desert. 57Fe Mössbauer spectroscopy was used for quantitative analysis of the degree of weathering of the meteorites, through the determination of the proportions of the various Fe-bearing phases and in particular the amount of oxidized iron in the terrestrial alteration products. The abundance of ferric ions in weathered chondrites can be related to specific precursor compositions and to the level of terrestrial weathering. The aim of the study was the identification, quantification and differentiation of the weathering products in the ordinary chondrites found in the San Juan area of Atacama Desert.

Munayco, P.; Munayco, J.; Valenzuela, M.; Rochette, P.; Gattacceca, J.; Scorzelli, R. B.

2014-01-01

246

Weathering processes and the composition of inorganic material transported through the orinoco river system, Venezuela and Colombia  

USGS Publications Warehouse

The composition of river-borne material in the Orinoco River system is related primarily to erosion regime, which in turn is related to tectonic setting; especially notable is the contrast between material derived from tectonically active mountain belts and that from stable cratonic regions. For a particular morpho-tectonic region, the compositional suites of suspended sediment, bed material, overback deposits, and dissolved phases are fairly uniform are are typically distinct from whose of other regions. For each region, a consistent set of chemical weathering reactions can be formulated to explain the composition of dissolved and solid loads. In developing these formulations, erosion on slopes and storage of solids in soils and alluvial sediments are important considerations. Compositionally verymature sediment is derived from areas of thick soils where erosion is transport limited and from areas where sediments are stored for extended periods of time in alluvial deposits. Compositionally immature sediments are derived from tectonically active mountain belts where erosion is weathering limited. Weathering-limited erosion also is important in the elevated parts of the Guayana Shield within areas of sleep topography. Compared to the mountain belts, sediments derived from elevated parts of the Shield are more mature. A greater degree of chemical weathering seems to be needed to erode the rock types typical of the Shield. The major-element chemistry and mineral composition of sediment delivered by the Orinoco River to the ocean are controlled by rivers that have their headwaters in mountain belts and cross the Llanos, a region of alluvial plains within the foreland basin. The composition of sediments in rivers that drain the Shield seems to be established primarily at the site of soil formation, whereas for rivers that drain the mountain belts, additional weathering occurs during s episodes of storage on alluvial plains as sediments are transported across the Llanos to the main stem of the Orinoco. After mixing into the main stem, there seems to be little subsequent alteration of sediment. ?? 1991.

Stallard, R.F.; Koehnken, L.; Johnsson, M.J.

1991-01-01

247

Influence of different natural physical fields on biological processes  

NASA Astrophysics Data System (ADS)

In space flight conditions gravity, magnetic, and electrical fields as well as ionizing radiation change both in size, and in direction. This causes disruptions in the conduct of some physical processes, chemical reactions, and metabolism in living organisms. In these conditions organisms of different phylogenetic level change their metabolic reactions undergo changes such as disturbances in ionic exchange both in lower and in higher plants, changes in cell morphology for example, gyrosity in Proteus ( Proteus vulgaris), spatial disorientation in coleoptiles of Wheat ( Triticum aestivum) and Pea ( Pisum sativum) seedlings, mutational changes in Crepis ( Crepis capillaris) and Arabidopsis ( Arabidopsis thaliana) seedling. It has been found that even in the absence of gravity, gravireceptors determining spatial orientation in higher plants under terrestrial conditions are formed in the course of ontogenesis. Under weightlessness this system does not function and spatial orientation is determined by the light flux gradient or by the action of some other factors. Peculiarities of the formation of the gravireceptor apparatus in higher plants, amphibians, fish, and birds under space flight conditions have been observed. It has been found that the system in which responses were accompanied by phase transition have proven to be gravity-sensitive under microgravity conditions. Such reactions include also the process of photosynthesis which is the main energy production process in plants. In view of the established effects of microgravity and different natural physical fields on biological processes, it has been shown that these processes change due to the absence of initially rigid determination. The established biological effect of physical fields influence on biological processes in organisms is the starting point for elucidating the role of gravity and evolutionary development of various organisms on Earth.

Mashinsky, A. L.

2001-01-01

248

Gendering processes in the field of physical education  

Microsoft Academic Search

In Finnish secondary schools, girls and boys are taught physical education (PE) in separate groups. A male teacher normally teaches the boys and a female teacher teaches the girls. Focusing on PE teachers’ comments in two different ethnographic studies of seventh graders (13–14?year?olds), we examine the processes that reproduce or challenge the gender system and the possibilities of agency in

Päivi Berg; Elina Lahelma

2010-01-01

249

Weather control  

Microsoft Academic Search

Weather modification, the intentional altering of atmospheric conditions to suit the purposes of humankind, has five basic forms: (1) fog dissipation; (2) rain and snow enhancement; (3) hail suppression; (4) lightning suppression; and (5) the abatement of severe storms such as hurricanes and tornadoes. The dissipation of fog and the seeding of clouds with dry ice or silver iodide to

Leepson

1980-01-01

250

Wonderful Weather  

NSDL National Science Digital Library

In this activity, learners conduct three experiments to examine temperature, the different stages of the water cycle, and how convection creates wind. These activities can be used individually or as a group for a lesson on weather. Note: boiling water is required for this activity; adult supervision required.

Workshop, Mission S.

2013-01-01

251

Weather Stations  

NSDL National Science Digital Library

This is a series of seven brief activities about Jupiter's atmosphere and weather. Learners will look at Jupiter's distinct banded appearance, violent storms, and clouds of many different colors. The activities are part of Explore! Jupiter's Family Secrets, a series designed to engage children in space and planetary science in libraries and informal learning environments.

252

Physical Processes in Strong Magnetic Fields of Neutron Stars  

E-print Network

Neutron stars have inferred surface magnetic fields of up to 10^{14} Gauss, in the case of radio pulsars, and up to possibly 10^{15} Gauss, in the case of Soft Gamma-Ray Repeaters and Anomalous X-ray Pulsars. In fields this high, QED effects will profoundly change the characteristics of continuum radiation processes such as synchrotron emission and Compton scattering and will also allow the possibility of additional physical processes such as one-photon pair production, vacuum polarization and photon splitting. Atomic line processes will also be significantly affected by the presence of strong fields. I will review some of the properties of radiation processes in strong magnetic fields that are most relevant to pulsars, SGRs and AXPs and the role they play in models for these sources.

Alice K. Harding

2003-04-07

253

The Weather Doctor  

NSDL National Science Digital Library

Published by Spectrum Educational Enterprises, The Weather Doctor Web site is maintained by meteorologist Keith Heidorn. Visitors to the site will find everything from the joys of weather watching, to making rain, to weather history, to much more. Coming from someone who clearly enjoys what they do, this site explores unique aspects of weather including weather people, weather history, and weather and arts.

Heidorn, Keith.

2002-01-01

254

Significant impacts of radiation physics in the Weather Research and Forecasting model on the precipitation and dynamics of the West African Monsoon  

NASA Astrophysics Data System (ADS)

Precipitation from the West African Monsoon (WAM) provides food security and supports the economy in the region. As a consequence of the intrinsic complexities of the WAM's evolution, accurate simulations of the WAM and its precipitation regime, through the application of regional climate models, are challenging. We used the coupled Weather Research and Forecasting (WRF) and Community Land Model (CLM) to explore impacts of radiation physics on the precipitation and dynamics of the WAM. Our results indicate that the radiation physics schemes not only produce biases in radiation fluxes impacting radiative forcing, but more importantly, result in large bias in precipitation of the WAM. Furthermore, the different radiation schemes led to variations in the meridional gradient of surface temperature between the north that is the Sahara desert and the south Guinean coastline. Climate diagnostics indicated that the changes in the meridional gradient of surface temperature affect the position and strength of the African Easterly Jet as well as the low-level monsoonal inflow from the Gulf of Guinea. The net result was that each radiation scheme produced differences in the WAM precipitation regime both spatially and in intensity. Such considerable variances in the WAM precipitation regime and dynamics, resulting from radiation representations, likely have strong feedbacks within the climate system and so have inferences when it comes to aspects of predicted climate change both for the region and globally.

Li, R.; Jin, J.; Wang, S.-Y.; Gillies, R. R.

2014-08-01

255

Tacoma Power Weatherization  

E-print Network

Tacoma Power Weatherization Specifications August 2009 KnowYourPower.com | #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition Page 2 #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition

256

Graphene growth process modeling: a physical-statistical approach  

NASA Astrophysics Data System (ADS)

As a zero-band semiconductor, graphene is an attractive material for a wide variety of applications such as optoelectronics. Among various techniques developed for graphene synthesis, chemical vapor deposition on copper foils shows high potential for producing few-layer and large-area graphene. Since fabrication of high-quality graphene sheets requires the understanding of growth mechanisms, and methods of characterization and control of grain size of graphene flakes, analytical modeling of graphene growth process is therefore essential for controlled fabrication. The graphene growth process starts with randomly nucleated islands that gradually develop into complex shapes, grow in size, and eventually connect together to cover the copper foil. To model this complex process, we develop a physical-statistical approach under the assumption of self-similarity during graphene growth. The growth kinetics is uncovered by separating island shapes from area growth rate. We propose to characterize the area growth velocity using a confined exponential model, which not only has clear physical explanation, but also fits the real data well. For the shape modeling, we develop a parametric shape model which can be well explained by the angular-dependent growth rate. This work can provide useful information for the control and optimization of graphene growth process on Cu foil.

Wu, Jian; Huang, Qiang

2014-09-01

257

R-process nucleosynthesis calculations with complete nuclear physics input  

E-print Network

The r-process constitutes one of the major challenges in nuclear astrophysics. Its astrophysical site has not yet been identified but there is observational evidence suggesting that at least two possible sites should contribute to the solar system abundance of r-process elements and that the r-process responsible for the production of elements heavier than Z=56 operates quite robustly producing always the same relative abundances. From the nuclear-physics point of view the r-process requires the knowledge of a large number of reaction rates involving exotic nuclei. These include neutron capture rates, beta-decays and fission rates, the latter for the heavier nuclei produced in the r-process. We have developed for the first time a complete database of reaction rates that in addition to neutron-capture rates and beta-decay half-lives includes all possible reactions that can induce fission (neutron-capture, beta-decay and spontaneous fission) and the corresponding fission yields. In addition, we have implemented these reaction rates in a fully implicit reaction network. We have performed r-process calculations for the neutrino-driven wind scenario to explore whether or not fission can contribute to provide a robust r-process pattern.

I. Petermann; A. Arcones; A. Keli?; K. Langanke; G. Martínez-Pinedo; K. -H. Schmidt; W. R. Hix; I. Panov; T. Rauscher; F. -K. Thielemann; N. Zinner

2008-12-04

258

Preliminary observations on the impact of complex stress histories on sandstone response to salt weathering: laboratory simulations of process combinations  

Microsoft Academic Search

Historic sandstone structures carry an inheritance, or a ‘memory’, of past stresses that the stone has undergone since its\\u000a placement in a façade. This inheritance, which conditions present day performance, may be made up of long-term exposure to\\u000a a combination of low magnitude background environmental factors (for example, salt weathering, temperature and moisture cycling)\\u000a and, superimposed upon these, less frequent

S. McCabe; B. J. Smith; P. A. Warke

2007-01-01

259

Exploring clouds, weather, climate, and modeling using bilingual content and activities from the Windows to the Universe program and the Center for Multiscale Modeling of Atmospheric Processes  

NASA Astrophysics Data System (ADS)

The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its third year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences through its affiliation with the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). W2U web pages are written at three levels in English and Spanish. This information targets learners at all levels, educators, and families who seek to understand and share resources and information about the nature of weather and the climate system, and career role models from related research fields. This resource can also be helpful to educators who are building bridges in the classroom between the sciences, the arts, and literacy. Visitors to the W2U's CMMAP web portal can access a beautiful new clouds image gallery; information about each cloud type and the atmospheric processes that produce them; a Clouds in Art interactive; collections of weather-themed poetry, art, and myths; links to games and puzzles for children; and extensive classroom- ready resources and activities for K-12 teachers. Biographies of CMMAP scientists and graduate students are featured. Basic science concepts important to understanding the atmosphere, such as condensation, atmosphere pressure, lapse rate, and more have been developed, as well as 'microworlds' that enable students to interact with experimental tools while building fundamental knowledge. These resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

Foster, S. Q.; Johnson, R. M.; Randall, D.; Denning, S.; Russell, R.; Gardiner, L.; Hatheway, B.; Genyuk, J.; Bergman, J.

2008-12-01

260

Weather Cycles  

NSDL National Science Digital Library

We are professionals in the teaching profession. We designed this project for children ranging from 4th grade to 6th grade. This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. YOU WILL NEED: Paper with copied questions, Overhead projector and Students broken up into groups of 3. Form groups of three. Have each group explore the following simulation: Weather Maker Simulator Have students use the simulation to answer the following questions on paper. They should be discussing the questions in their groups. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What ...

Mitchell, Mrs.

2010-09-23

261

Weather control  

SciTech Connect

Weather modification, the intentional altering of atmospheric conditions to suit the purposes of humankind, has five basic forms: (1) fog dissipation; (2) rain and snow enhancement; (3) hail suppression; (4) lightning suppression; and (5) the abatement of severe storms such as hurricanes and tornadoes. The dissipation of fog and the seeding of clouds with dry ice or silver iodide to produce rain are the most successful weather modification techniques. Both are used extensively and with varying degrees of success in the United States and around the world. Cloud seeding, though, is not effective in easing the harshness of a drought, such as the one that hit the Southwest, Midwest and Great Plains this summer.

Leepson, M.

1980-09-05

262

Weather Watchers  

NSDL National Science Digital Library

Students are introduced to some essential meteorology concepts so they more fully understand the impact of meteorological activity on air pollution control and prevention. First, they develop an understanding of the magnitude and importance of air pressure. Next, they build a simple aneroid barometer to understand how air pressure information is related to weather prediction. Then, students explore the concept of relative humidity and its connection to weather prediction. Finally, students learn about air convection currents and temperature inversions. In an associated literacy activity, students learn how scientific terms are formed using Latin and Greek roots, prefixes and suffixes, and are introduced to the role played by metaphor in language development. Note: Some of these activities can be conducted simultaneously with the air quality activity (What Color Is Your Air Today?) of Air Pollution unit, Lesson 1.

Integrated Teaching And Learning Program

263

Salt Weathering on Mars  

Microsoft Academic Search

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement,

E. Jagoutz

2006-01-01

264

Salt weathering on Mars  

Microsoft Academic Search

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement,

E. Jagoutz

2004-01-01

265

Compact effector optics for processing in limited physical access situations  

NASA Astrophysics Data System (ADS)

A major advantage of fiber-optic beam delivery in laser materials processing is the ability to guide the laser power to the location where it is needed, leaving the laser itself remote and protected from the process. This is of special importance if the processing is to be performed in a hazardous environment. Particular problems are faced by the nuclear industry where weld repair and surface treatment work are required inside radioactive installations. By use of fiber beam delivery, only part of the delivery system and effector optics become contaminated, but the expensive laser system does not. However, in many cases the region where repair is required is not only radioactive but has only limited physical access, e.g., inside tubes or into corners, which prevents use of standard effector optics. We present a new design to deal with such constraints of a 2-mm outer diameter employing a hollow waveguide and gas shielding. This design is optically characterized and its performance assessed in welding and surface treatment applications. The potential of this compact effector optics in limited physical access situations is clearly demonstrated.

Kuhn, Andreas; Fox, Mahlen D. T.; French, Paul W.; Hettrick, Simon; Hand, Duncan P.; Shi, Yi-Wei; Matsuura, Yuji; Miyagi, Mitsunobu; Watkins, Kenneth G.; Ireland, Clive L. M.; Jones, Julian D. C.

2003-09-01

266

Weather from the Stratosphere?  

NASA Technical Reports Server (NTRS)

Is the stratosphere, the atmospheric layer between about 10 and 50 km, important for predicting changes in weather and climate? The traditional view is that the stratosphere is a passive recipient of energy and waves from weather systems in the underlying troposphere, but recent evidence suggests otherwise. At a workshop in Whistler, British Columbia (1), scientists met to discuss how the stratosphere responds to forcing from below, initiating feedback processes that in turn alter weather patterns in the troposphere. The lowest layer of the atmosphere, the troposphere, is highly dynamic and rich in water vapor, clouds, and weather. The stratosphere above it is less dense and less turbulent (see the figure). Variability in the stratosphere is dominated by hemispheric-scale changes in airflow on time scales of a week to several months. Occasionally, however, stratospheric air flow changes dramatically within just a day or two, with large-scale jumps in temperature of 20 K or more. The troposphere influences the stratosphere mainly through atmospheric waves that propagate upward. Recent evidence shows that the stratosphere organizes this chaotic wave forcing from below to create long-lived changes in the stratospheric circulation. These stratospheric changes can feed back to affect weather and climate in the troposphere.

Baldwin, Mark P.; Thompson, David W. J.; Shuckburgh, Emily F.; Norton, Warwick A.; Gillett, Nathan P.

2006-01-01

267

National Weather Service  

MedlinePLUS

HOME FORECAST Local Graphical Aviation Marine Rivers and Lakes Hurricanes Severe Weather Fire Weather Sun/Moon Long Range Forecasts Climate Prediction PAST WEATHER Past Weather Heating/Cooling Days Monthly ...

268

Spring Deposits on Mars: Physical Processes from Terrestrial Analogs  

NASA Technical Reports Server (NTRS)

An important first step in the current Mars exploration strategy is the detection of sites where there is evidence for past or present near-surface water on Mars. This study evaluates the large-scale morphology of spring deposits and the physical processes of their formation, growth, and evolution in terms that relate to (1) their identification in image data, (2) their formation, evolution, and preservation in the environment of Mars, and (3) their potential as sites of long-term or late stage shallow groundwater emergence at the surface of Mars.

Crumpler, L. S.

2003-01-01

269

Physical process Physical process  

E-print Network

mechanisms ! Voltage fluctuations (temporal) ! Current fluctuations (temporal) ! Electric field variations Force-time history #12;8 Force-time history Velocity-time history #12;9 Operation Source unit

Berlin,Technische Universität

270

The r-process nucleosynthesis: Nuclear physics challenges  

SciTech Connect

About half of the nuclei heavier than iron observed in nature are produced by the socalled rapid neutron capture process, or r-process, of nucleosynthesis. The identification of the astrophysics site and the specific conditions in which the r-process takes place remains, however, one of the still-unsolved mysteries of modern astrophysics. Another underlying difficulty associated with our understanding of the r-process concerns the uncertainties in the predictions of nuclear properties for the few thousands exotic neutron-rich nuclei involved and for which essentially no experimental data exist. The present contribution emphasizes some important future challenges faced by nuclear physics in this problem, particularly in the determination of the nuclear structure properties of exotic neutron-rich nuclei as well as their radiative neutron capture rates and their fission probabilities. These quantities are particularly relevant to determine the composition of the matter resulting from the r-process. Their impact on the r-abundance distribution resulting from the decompression of neutron star matter is discussed.

Goriely, S. [Institut d'Astronomie et d'Astrophysique, Universite Libre de Bruxelles Campus de la Plaine, CP 226, 1050 Brussels (Belgium)

2012-10-20

271

Weathering effects on the structure and reactivity of US coals: Final report, July 15, 1984-July 14, 1987. [Many data  

SciTech Connect

This report covers the work performed from July 1984 to July 1987 under the project entitled ''Weathering Effects on Structure and Reactivity of US Coals'' (grant number FG22-84PC70798). The main objectives of the study were to investigate the structural changes in coal during the weathering process as well as to develop a simple, reliable weathering index, which can monitor indirectly the weathering-induced changes in physical and chemical properties. Although there have been numerous publications on structure and reactivity of coal, most data reported in the literature thus far have been obtained on coal samples of uncertain weathering status and therefore need to be interpreted with great caution. Weathering has a profound effect on many important coal properties such as heating value, caking characteristics, acidity, flotability and reactivity in liquefaction, combustion and gasification processes. The objective of developing a weathering index is to predict these coal property changes due to weathering without resorting to real-time measurements or pilot plant runs. This report is comprised of four main chapters: I. Structural Changes due to Weathering; II. Material Balance in Weathering Process; III. Development of a Reliable Weathering Index; and IV. Proposed Weathering Mechanisms. A battery of sophisticated analytical tools and techniques was employed during this study. Pyrolysis mass spectrometry in time-integrated, as well as in time-resolved modes with computer-aided data analysis techniques (such as factor and discriminant analysis), gas chromatography, thermogravimetry/mass spectrometry and solvent extraction were used for determining the role of oxygen during the weathering process. Pyrolysis mass spectrometry, Free Swelling Index and a novel slurry pH technique were employed as weathering indicators. 170 refs.

Meuzelaar, H.L.C.; Hill, G.R.; Yun, Yongseung; Jakab, E.; Windig, W.; Urban, D.; Yon, Kyung Yol; Oestreich, J.; East, J.

1987-01-01

272

Influence of wheat kernel physical properties on the pulverizing process.  

PubMed

The physical properties of wheat kernel were determined and related to pulverizing performance by correlation analysis. Nineteen samples of wheat cultivars about similar level of protein content (11.2-12.8 % w.b.) and obtained from organic farming system were used for analysis. The kernel (moisture content 10 % w.b.) was pulverized by using the laboratory hammer mill equipped with round holes 1.0 mm screen. The specific grinding energy ranged from 120 kJkg(-1) to 159 kJkg(-1). On the basis of data obtained many of significant correlations (p?physical properties and pulverizing process of wheat kernel, especially wheat kernel hardness index (obtained on the basis of Single Kernel Characterization System) and vitreousness significantly and positively correlated with the grinding energy indices and the mass fraction of coarse particles (> 0.5 mm). Among the kernel mechanical properties determined on the basis of uniaxial compression test only the rapture force was correlated with the impact grinding results. The results showed also positive and significant relationships between kernel ash content and grinding energy requirements. On the basis of wheat physical properties the multiple linear regression was proposed for predicting the average particle size of pulverized kernel. PMID:25328207

Dziki, Dariusz; Cacak-Pietrzak, Gra?yna; Mi?, Antoni; Jo?czyk, Krzysztof; Gawlik-Dziki, Urszula

2014-10-01

273

To Photon Concept and to Physics of Quantum Absorption Process  

E-print Network

The status of the photon in the modern physics was analysed. Within the frames of the Standard Model of particle physics the photon is considered to be the genuine elementary particle, being to be the messenger of the electromagnetic interaction to which are subject charged particles. In contrast, the experts in quantum electodynamics (in particular, in quantum optics) insist, that the description of an photon to be the particle is impossible. The given viewpoint was carefully analysed and its falseness was proved. The expression for a photon wave function is presented. So, the status of the photon in quantum electodynamics was restored. The physics of a quantum absorption process is analysed. It is argued in accordance with Dirac guess, that the photon revival takes place by its absorption. Being to be a soliton, it seems to be keeping safe after an energy absorption in a pinned state, possessing the only by spin. It is shown, that the time of the transfer of absorbing systems in an excited state is finite a...

Yerchuck, Dmitri; Dovlatova, Alla; Stelmakh, Vyacheslav; Borovik, Felix

2014-01-01

274

To Photon Concept and to Physics of Quantum Absorption Process  

E-print Network

The status of the photon in the modern physics was analysed. Within the frames of the Standard Model of particle physics the photon is considered to be the genuine elementary particle, being to be the messenger of the electromagnetic interaction to which are subject charged particles. In contrast, the experts in quantum electodynamics (in particular, in quantum optics) insist, that the description of an photon to be the particle is impossible. The given viewpoint was carefully analysed and its falseness was proved. The expression for a photon wave function is presented. So, the status of the photon in quantum electodynamics was restored. The physics of a quantum absorption process is analysed. It is argued in accordance with Dirac guess, that the photon revival takes place by its absorption. Being to be a soliton, it seems to be keeping safe after an energy absorption in a pinned state, possessing the only by spin. It is shown, that the time of the transfer of absorbing systems in an excited state is finite and moreover, that it can govern the stationary signal registered. The given result is significant for the all stationary spectroscopy, in which at present the transfer of absorbing systems in an excited state is considered to be instantaneous.

Dmitri Yerchuck; Yauhen Yerchak; Alla Dovlatova; Vyacheslav Stelmakh; Felix Borovik

2014-06-03

275

Solar physics applications of computer graphics and image processing  

NASA Technical Reports Server (NTRS)

Computer graphics devices coupled with computers and carefully developed software provide new opportunities to achieve insight into the geometry and time evolution of scalar, vector, and tensor fields and to extract more information quickly and cheaply from the same image data. Two or more different fields which overlay in space can be calculated from the data (and the physics), then displayed from any perspective, and compared visually. The maximum regions of one field can be compared with the gradients of another. Time changing fields can also be compared. Images can be added, subtracted, transformed, noise filtered, frequency filtered, contrast enhanced, color coded, enlarged, compressed, parameterized, and histogrammed, in whole or section by section. Today it is possible to process multiple digital images to reveal spatial and temporal correlations and cross correlations. Data from different observatories taken at different times can be processed, interpolated, and transformed to a common coordinate system.

Altschuler, M. D.

1985-01-01

276

Weather Forecasting for Weather Derivatives  

Microsoft Academic Search

Abstract: We take a nonstructural time-series approach to modeling and forecasting daily average temperature in ten U.S. cities, and we inquire systematically as to whether it may prove useful from the vantage point of participants in the weather derivatives market. The answer is, perhaps surprisingly, yes. Time series modeling reveals both strong conditional mean dynamics,and conditional variance dynamics in daily

Sean D. Campbell; Francis X. Diebold

2005-01-01

277

Mountain Weather  

NSDL National Science Digital Library

Mountains can be awe-inspiring both for the vistas they provide and for the weather events and long-term climate systems they support. This interactive feature illustrates how a moisture-laden air mass interacts with a mountain slope to produce characteristic patterns of precipitation over the mountain and surrounding areas. Viewers can see how clouds and precipitation form as the air mass ascends the windward side of the peak, and observe the rain shadow created on the leeward side by the descending, warmed, and moisture-depleted air. A background essay and list of discussion questions supplement the interactive feature.

278

CLARA: A Contemporary Approach to Physics Data Processing  

SciTech Connect

In traditional physics data processing (PDP) systems, data location is static and is accessed by analysis applications. In comparison, CLARA (CLAS12 Reconstruction and Analysis framework) is an environment where data processing algorithms filter continuously flowing data. In CLARA's domain of loosely coupled services, data is not stored, but rather flows from one service to another, mutating constantly along the way. Agents, performing event processing, can then subscribe to particular data/events at any stage of the data transformation, and make intricate decisions (e.g. particle ID) by correlating events from multiple, parallel data streams and/or services. This paper presents a PDP application development framework based on service oriented and event driven architectures. This system allows users to design (Java, C++, and Python languages are supported) and deploy data processing services, as well as dynamically compose PDP applications using available services. The PDP service bus provides a layer on top of a distributed pub-sub middleware implementation, which allows complex service composition and integration without writing code. Examples of service creation and deployment, along with the CLAS12 track reconstruction application design will be presented.

V Gyurjyan, D Abbott, J Carbonneau, G Gilfoyle, D Heddle, G Heyes, S Paul, C Timmer, D Weygand, E Wolin

2011-12-01

279

Contaminants from Cretaceous Black Shale Part 1: Natural weathering processes controlling contaminant cycling in Mancos Shale, southwestern United States, with emphasis on salinity and selenium  

USGS Publications Warehouse

Soils derived from black shale can accumulate high concentrations of elements of environmental concern, especially in regions with semiarid to arid climates. One such region is the Colorado River basin in the southwestern United States where contaminants pose a threat to agriculture, municipal water supplies, endangered aquatic species, and water-quality commitments to Mexico. Exposures of Cretaceous Mancos Shale (MS) in the upper basin are a major contributor of salinity and selenium in the Colorado River. Here, we examine the roles of geology, climate, and alluviation on contaminant cycling (emphasis on salinity and Se) during weathering of MS in a Colorado River tributary watershed. Stage I (incipient weathering) began perhaps as long ago as 20 ka when lowering of groundwater resulted in oxidation of pyrite and organic matter. This process formed gypsum and soluble organic matter that persist in the unsaturated, weathered shale today. Enrichment of Se observed in laterally persistent ferric oxide layers likely is due to selenite adsorption onto the oxides that formed during fluctuating redox conditions at the water table. Stage II weathering (pedogenesis) is marked by a significant decrease in bulk density and increase in porosity as shale disaggregates to soil. Rainfall dissolves calcite and thenardite (Na2SO4) at the surface, infiltrates to about 1 m, and precipitates gypsum during evaporation. Gypsum formation (estimated 390 kg m?2) enriches soil moisture in Na and residual SO4. Transpiration of this moisture to the surface or exposure of subsurface soil (slumping) produces more thenardite. Most Se remains in the soil as selenite adsorbed to ferric oxides, however, some oxidizes to selenate and, during wetter conditions is transported with soil moisture to depths below 3 m. Coupled with little rainfall, relatively insoluble gypsum, and the translocation of soluble Se downward, MS landscapes will be a significant nonpoint source of salinity and Se to the Colorado River well into the future. Other trace elements weathering from MS that are often of environmental concern include U and Mo, which mimic Se in their behavior; As, Co, Cr, Cu, Ni, and Pb, which show little redistribution; and Cd, Sb, V, and Zn, which accumulate in Stage I shale, but are lost to varying degrees from upper soil intervals. None of these trace elements have been reported previously as contaminants in the study area.

Tuttle, Michele L.; Fahy, Juli W.; Elliott, John G.; Grauch, Richard I.; Stillings, Lisa L.

2013-01-01

280

Physical Processes Involved In Yellow Sea Solitary Waves  

NASA Astrophysics Data System (ADS)

The study area is located south of the Shandong peninsula. In this area, soliton gener- ation and propagation studies are per formed with the Lamb(1994) model. The model is nonhydrostatic and is formulated in 2 1/2 dimensions for terrain following c oordi- nates. In the area, 20 to 30 m topographic variations over distances of 10 to 20 km are found to occur in the digit al atlas of Choi (1999). The area is shallow with maximum depths ranging from 40 m to 70 m. Along the southern boundary of the region the semi-diurnal tidal strength magnitude varies from .6 m/sec to 1.2 m/sec, Fang(1994). We show that, for sum mer conditions, the existing physical processes associated with the semi-diurnal tidal flow over the topographic variations , in the shelfbreak region, lead to the formation of internal bores in the model simulations. Through acting phys- ical proce sses, the internal bores propagate on and off the shelf. A disintegration process of internal bores into solitary waves occ urs through frequency and ampli- tude dispersion. SAR observations of the area show images containing six events con- sisting of internal bores and solitary waves that travel in a well-defined direction for two and a half days. The origin of the trains appeared to be at a point along a steep topo graphic drop. The SAR observations are used for guiding and tuning the model simulations, by comparing spectra of observed and modeled wavelengths. The tuned model yields wavelengths that are within a factor of 2 of the SAR data. The modeled amp litudes are within a factor of 2 of amplitudes obtained with a two-layer model and the SAR data The signature on the acoustical field of ongoing physical processes through the interaction of the resultant oceanic struct ure with the acoustical field is pursued. Internal bore and solitary wave structures interact with the acoustic field. A re distribution of acoustical energy to higher acoustical modes occurs at some fre- quencies. Mode decomposition of the acoustic fields indicate that mode conversions necessary for anomalous signal losses are present. The acoustical process of redistr ibuting acoustical energy to higher modes is coupled to oceanographic processes as- sociated with a propagating solitary wave .

Warn-Varnas, A.; Chin-Bing, S.; King, D.; Lamb, K.; Hawkins, J.; Teixeira, M.

281

Contrast Restoration of Weather Degraded Images  

Microsoft Academic Search

Images of outdoor scenes captured in bad weather suffer from poor contrast. Under bad weather conditions, the light reaching a camera is severely scattered by the atmosphere. The resulting decay in contrast varies across the scene and is exponential in the depths of scene points. Therefore, traditional space invariant image processing techniques are not sufficient to remove weather effects from

Srinivasa G. Narasimhan; Shree K. Nayar

2003-01-01

282

Honeycomb Weathering of Limestone Formations  

USGS Multimedia Gallery

Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time....

2010-08-16

283

Framework for Understanding LENR Processes, Using Ordinary Condensed Matter Physics  

NASA Astrophysics Data System (ADS)

As I have emphasizedootnotetextS.R. Chubb, Proc. ICCF10 (in press). Also, http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf, S.R. Chubb, Trans. Amer. Nuc. Soc. 88 , 618 (2003)., in discussions of Low Energy Nuclear Reactions(LENRs), mainstream many-body physics ideas have been largely ignored. A key point is that in condensed matter, delocalized, wave-like effects can allow large amounts of momentum to be transferred instantly to distant locations, without any particular particle (or particles) acquiring high velocity through a Broken Gauge Symmetry. Explicit features in the electronic structure explain how this can occur^1 in finite size PdD crystals, with real boundaries. The essential physics^1 can be related to standard many-body techniquesootnotetextBurke,P.G. and K.A. Berrington, Atomic and Molecular Processes:an R matrix Approach (Bristol: IOP Publishing, 1993).. In the paper, I examine this relationship, the relationship of the theory^1 to other LENR theories, and the importance of certain features (for example, boundaries^1) that are not included in the other LENR theories.

Chubb, Scott

2005-03-01

284

Convection in the Physical Vapor Transport Process-I: Thermal  

NASA Technical Reports Server (NTRS)

The effects of convection on diffusive-convective physical vapor transport process are examined computationally. We analyze conditions ranging from typical laboratory conditions to conditions achievable only in a low gravity environment. This corresponds to thermal Rayleigh numbers Ra, ranging from 1.80 x 10 to 1.92 x 10(exp 6). Our results indicate that the effect of the sublimation and condensation fluxes at the boundaries is to increase the threshold of instability. For typical ground based conditions, time dependent oscillatory convection can occur. This results in unsteady transport, and non- uniform temperature and concentration gradients at the crystal interface. Spectral analysis of the flow field shows parametric regions exhibiting both an oscillatory approach to steady state and a chaotic transient to a periodic state. Low gravity conditions stabilize the flow field. Convective effects are effectively reduced, thus resulting in uniform temperature and concentration gradients at the interface, a desirable condition for crystal growth.

Duval, Walter M. B.

1994-01-01

285

Convection in the Physical Vapor Transport Process. 1; Thermal  

NASA Technical Reports Server (NTRS)

The effects of convection on diffusive-convective physical vapor transport process are examined computationally. We analyze conditions ranging from typical laboratory conditions to conditions achievable only in a low gravity environment. This corresponds to thermal Rayleigh numbers Ra(sub tau) ranging from 1.80 x 10 to 1.92 x 10(exp 6). Our results indicate that the effect of the sublimation and condensation fluxes at the boundaries is to increase the threshold of instability. For typical ground based conditions, time dependent oscillatory convection can occur. This results in unsteady transport, and non-uniform temperature and concentration gradients at the crystal interface. Spectral analysis of the flow field shows parametric regions exhibiting both an oscillatory approach to steady state and a chaotic transient to a periodic state. Low gravity conditions stabilize the flow field. Convective effects are effectively reduced, thus resulting in uniform temperature and concentration gradients at the interface, a desirable condition for crystal growth.

Duval, Walter M. B.

1994-01-01

286

Physical processes associated with current collection by plasma contactors  

NASA Technical Reports Server (NTRS)

Recent flight data confirms laboratory observations that the release of neutral gas increases plasma sheath currents. Plasma contactors are devices which release a partially ionized gas in order to enhance the current flow between a spacecraft and the space plasma. Ionization of the expellant gas and the formation of a double layer between the anode plasma and the space plasma are the dominant physical processes. A theory is presented of the interaction between the contactor plasma and the background plasma. The conditions for formation of a double layer between the two plasmas are derived. Double layer formation is shown to be a consequence of the nonlinear response of the plasmas to changes in potential. Numerical calculations based upon this model are compared with laboratory measurements of current collection by hollow cathode-based plasma contactors.

Katz, Ira; Davis, Victoria A.

1990-01-01

287

Physical processes mediating climate change impacts on regional sea ecosystems  

NASA Astrophysics Data System (ADS)

Regional seas are exceptionally vulnerable to climate change, yet are the most directly societally important regions of the marine environment. The combination of widely varying conditions of mixing, forcing, geography (coastline and bathymetry) and exposure to the open-ocean makes these seas subject to a wide range of physical processes that mediates how large scale climate change impacts on these seas' ecosystems. In this paper we explore these physical processes and their biophysical interactions, and the effects of atmospheric, oceanic and terrestrial change on them. Our aim is to elucidate the controlling dynamical processes and how these vary between and within regional seas. We focus on primary production and consider the potential climatic impacts: on long term changes in elemental budgets, on seasonal and mesoscale processes that control phytoplankton's exposure to light and nutrients, and briefly on direct temperature response. We draw examples from the MEECE FP7 project and five regional models systems using ECOSMO, POLCOMS-ERSEM and BIMS_ECO. These cover the Barents Sea, Black Sea, Baltic Sea, North Sea, Celtic Seas, and a region of the Northeast Atlantic, using a common global ocean-atmosphere model as forcing. We consider a common analysis approach, and a more detailed analysis of the POLCOMS-ERSEM model. Comparing projections for the end of the 21st century with mean present day conditions, these simulations generally show an increase in seasonal and permanent stratification (where present). However, the first order (low- and mid-latitude) effect in the open ocean projections of increased permanent stratification leading to reduced nutrient levels, and so to reduced primary production, is largely absent, except in the NE Atlantic. Instead, results show a highly heterogeneous picture of positive and negative change arising from the varying mixing and circulation conditions. Even in the two highly stratified, deep water seas (Black and Baltic Seas) the increase in stratification is not seen as a first order control on primary production. The approaches to downscaled experiment design and lessons learned from the MEECE project are also discussed.

Holt, J.; Schrum, C.; Cannaby, H.; Daewel, U.; Allen, I.; Artioli, Y.; Bopp, L.; Butenschon, M.; Fach, B. A.; Harle, J.; Pushpadas, D.; Salihoglu, B.; Wakelin, S.

2014-02-01

288

Adaptive Numerical Algorithms in Space Weather Modeling  

NASA Technical Reports Server (NTRS)

Space weather describes the various processes in the Sun-Earth system that present danger to human health and technology. The goal of space weather forecasting is to provide an opportunity to mitigate these negative effects. Physics-based space weather modeling is characterized by disparate temporal and spatial scales as well as by different physics in different domains. A multi-physics system can be modeled by a software framework comprising of several components. Each component corresponds to a physics domain, and each component is represented by one or more numerical models. The publicly available Space Weather Modeling Framework (SWMF) can execute and couple together several components distributed over a parallel machine in a flexible and efficient manner. The framework also allows resolving disparate spatial and temporal scales with independent spatial and temporal discretizations in the various models. Several of the computationally most expensive domains of the framework are modeled by the Block-Adaptive Tree Solar wind Roe Upwind Scheme (BATS-R-US) code that can solve various forms of the magnetohydrodynamics (MHD) equations, including Hall, semi-relativistic, multi-species and multi-fluid MHD, anisotropic pressure, radiative transport and heat conduction. Modeling disparate scales within BATS-R-US is achieved by a block-adaptive mesh both in Cartesian and generalized coordinates. Most recently we have created a new core for BATS-R-US: the Block-Adaptive Tree Library (BATL) that provides a general toolkit for creating, load balancing and message passing in a 1, 2 or 3 dimensional block-adaptive grid. We describe the algorithms of BATL and demonstrate its efficiency and scaling properties for various problems. BATS-R-US uses several time-integration schemes to address multiple time-scales: explicit time stepping with fixed or local time steps, partially steady-state evolution, point-implicit, semi-implicit, explicit/implicit, and fully implicit numerical schemes. Depending on the application, we find that different time stepping methods are optimal. Several of the time integration schemes exploit the block-based granularity of the grid structure. The framework and the adaptive algorithms enable physics based space weather modeling and even forecasting.

Toth, Gabor; vanderHolst, Bart; Sokolov, Igor V.; DeZeeuw, Darren; Gombosi, Tamas I.; Fang, Fang; Manchester, Ward B.; Meng, Xing; Nakib, Dalal; Powell, Kenneth G.; Stout, Quentin F.; Glocer, Alex; Ma, Ying-Juan; Opher, Merav

2010-01-01

289

The Weather Dude  

NSDL National Science Digital Library

The Weather Dude is a weather education Web site offered by meteorologist Nick Walker of The Weather Channel. For kids, the site offers a great online textbook entitled Weather Basics, which explains everything from precipitation to the seasons, using simple text and fun graphics. Other fun things for kids include weather songs, questions and quizzes, weather proverbs, and more. Teachers are also provided with helpful resources such as weather activity sheets and printable blank maps, as well as many other links to weather forecasts and information that will help make teaching about weather fun.

Walker, Nick.

2002-01-01

290

Plasma-based physical vapor deposition surface engineering processes  

NASA Astrophysics Data System (ADS)

Plasma-based physical vapor deposition (PVD) process developments occurring over the past few decades now allow the production of tribological coatings with properties which were previously unachievable. These new coatings will be critical in the creation of new products with improved functionality and performance, which will have a dramatic impact on, for example, their operating efficiency and lifetime. The key pioneers behind these PVD developments are discussed here, together with some significant process innovations. The latter include ionization-enhancing systems, such as thermionic assistance and arc evaporation, as well as unbalanced magnetron sputtering and magnetic plasma confinement. These developments have provided the impetus behind the recent growth in the technology field which we now know as surface engineering, and the recognition that surfaces provide the functionality and durability for almost all engineered products. Vacuum plasma technologies can thus be regarded as critical, not only for functional devices and thin film applications (for which their importance was previously most recognized), but also for structural product applications; they will thus underpin the entire spectrum of manufacturing industry.

Matthews, Allan

2003-09-01

291

A New Approach to Understanding Brown Dwarf Weather  

NASA Astrophysics Data System (ADS)

Over 130 HST orbits and 3000 Spitzer hours have been dedicated to observing variability in the emission of brown dwarfs, but we do not yet understand the physical processes that cause brown dwarf weather. The aim of the proposed work is to build the modeling tools to turn brown dwarf light curves into constraints on their atmospheric physics. Light curves of variable brown dwarfs are not simple sinusoids, but show spectral dependence in both amplitude and phase. Many objects exhibit evolution in the amplitude or shape of the light curve from one observation to another, indicating evolution of weather patterns. These complexities mean that while the two likely causes of variability--patchy clouds and temperature perturbations--should have distinct spectral signatures, the data are proving challenging to explain with simple prescriptions. Our tool to understand this extrasolar weather is to use a retrieval technique to extract the physical parameters that cause brown dwarf variability, directly from brown dwarf spectra. Using this tool with the information-rich HST data, we probe the temperature and cloud structure in multiple spatial dimensions as well as the time-evolution of these structures. These constraints provide crucial information for the development of atmospheric dynamical models, currently in their infancy for brown dwarfs. The retrieval technique we propose will allow us to leave the confines of pre-calculated grid models and measure the causes of brown dwarf weather directly from spectra. This tool will provide the information necessary to understand the atmospheric physics underlying warm substellar weather, decades before we can study weather on exoplanets.

Morley, Caroline

2014-10-01

292

Compensation for Lithography Induced Process Variations during Physical Design  

NASA Astrophysics Data System (ADS)

This dissertation addresses the challenge of designing robust integrated circuits in the deep sub micron regime in the presence of lithography process variability. By extending and combining existing process and circuit analysis techniques, flexible software frameworks are developed to provide detailed studies of circuit performance in the presence of lithography variations such as focus and exposure. Applications of these software frameworks to select circuits demonstrate the electrical impact of these variations and provide insight into variability aware compact models that capture the process dependent circuit behavior. These variability aware timing models abstract lithography variability from the process level to the circuit level and are used to estimate path level circuit performance with high accuracy with very little overhead in runtime. The Interconnect Variability Characterization (IVC) framework maps lithography induced geometrical variations at the interconnect level to electrical delay variations. This framework is applied to one dimensional repeater circuits patterned with both 90nm single patterning and 32nm double patterning technologies, under the presence of focus, exposure, and overlay variability. Studies indicate that single and double patterning layouts generally exhibit small variations in delay (between 1--3%) due to self compensating RC effects associated with dense layouts and overlay errors for layouts without self-compensating RC effects. The delay response of each double patterned interconnect structure is fit with a second order polynomial model with focus, exposure, and misalignment parameters with 12 coefficients and residuals of less than 0.1ps. The IVC framework is also applied to a repeater circuit with cascaded interconnect structures to emulate more complex layout scenarios, and it is observed that the variations on each segment average out to reduce the overall delay variation. The Standard Cell Variability Characterization (SCVC) framework advances existing layout-level lithography aware circuit analysis by extending it to cell-level applications utilizing a physically accurate approach that integrates process simulation, compact transistor models, and circuit simulation to characterize electrical cell behavior. This framework is applied to combinational and sequential cells in the Nangate 45nm Open Cell Library, and the timing response of these cells to lithography focus and exposure variations demonstrate Bossung like behavior. This behavior permits the process parameter dependent response to be captured in a nine term variability aware compact model based on Bossung fitting equations. For a two input NAND gate, the variability aware compact model captures the simulated response to an accuracy of 0.3%. The SCVC framework is also applied to investigate advanced process effects including misalignment and layout proximity. The abstraction of process variability from the layout level to the cell level opens up an entire new realm of circuit analysis and optimization and provides a foundation for path level variability analysis without the computationally expensive costs associated with joint process and circuit simulation. The SCVC framework is used with slight modification to illustrate the speedup and accuracy tradeoffs of using compact models. With variability aware compact models, the process dependent performance of a three stage logic circuit can be estimated to an accuracy of 0.7% with a speedup of over 50,000. Path level variability analysis also provides an accurate estimate (within 1%) of ring oscillator period in well under a second. Another significant advantage of variability aware compact models is that they can be easily incorporated into existing design methodologies for design optimization. This is demonstrated by applying cell swapping on a logic circuit to reduce the overall delay variability along a circuit path. By including these variability aware compact models in cell characterization libraries, design metrics such as circuit timing, power, area, and delay var

Chin, Eric Yiow-Bing

293

Identifying weathering sources and processes in an outlet glacier of the Greenland Ice Sheet using Ca and Sr isotope ratios  

NASA Astrophysics Data System (ADS)

Chemical and isotope data (?40Ca, ?44/42Ca, 87Sr/86Sr, ?18O) of river water samples were collected twice daily for 28 days in 2009 from the outlet river of Leverett Glacier, West Greenland. The water chemistry data was combined with detailed geochemical analysis and petrography of bulk rock, mineral separates and sediment samples in order to constrain the mineral weathering sources to the river. The average isotopic compositions measured in the river, with 2SD of all the values measured, were ?40Ca = +4.0 ± 1.4, ?44/42Ca = +0.60 ± 0.10‰ and 87Sr/86Sr = 0.74243 ± 0.00327. Based on changes in bulk meltwater discharge, the hydrochemical data was divided into three hydrological periods. The first period was marked by the tail-end of an outburst event and was characterised by water with decreasing suspended sediment concentrations (SSC), ion concentrations and pH. During the second hydrological period, discharge increased whilst 87Sr/86Sr decreased from 0.74550 to 0.74164. Based on binary mixing diagrams using 87Sr/86Sr with Na/Sr, Ca/Sr and ?40Ca, this is interpreted to reflect an increase in reactive mineral weathering, in particular epidote, as the water residence time decreases. The decrease in water residence time is a result of the evolution from a distributed (long water residence time) to a channelised (short water residence time) subglacial drainage network. The third hydrological period was defined as the period when overall discharge was decreasing. This hydrological period was marked by prominent diurnal cycles in discharge. During this period, significant correlations between ?44/42Ca and SSC and ?18O were observed which are suggestive of fractionation during adsorption. This study demonstrates the potential of radiogenic Ca to both identify temporally changing mineral sources in conjunction with 87Sr/86Sr values and to separate source and fractionation effects in ?44/42Ca values.

Hindshaw, Ruth S.; Rickli, Jörg; Leuthold, Julien; Wadham, Jemma; Bourdon, Bernard

2014-11-01

294

Physical Education Resources, Class Management, and Student Physical Activity Levels: A Structure-Process-Outcome Approach to Evaluating Physical Education Effectiveness  

ERIC Educational Resources Information Center

Background: This study was conducted to empirically evaluate specific human, curricular, and material resources that maximize student opportunities for physical activity during physical education (PE) class time. A structure-process-outcome model was proposed to identify the resources that influence the frequency of PE and intensity of physical

Bevans, Katherine B.; Fitzpatrick, Leslie-Anne; Sanchez, Betty M.; Riley, Anne W.; Forrest, Christopher

2010-01-01

295

Salt Weathering on Mars  

NASA Astrophysics Data System (ADS)

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974). However, irrespectively of the climatic environment a liquid brine is a necessity for salt induced fragmentation of rocks.M. C. Malin (1974) JGR Vol 79,26 p 3888-3894

Jagoutz, E.

2006-12-01

296

Writing TAFS for Winter Weather  

NSDL National Science Digital Library

"Writing TAFs for Winter Weather" is the fourth unit in the Distance Learning Aviation Course 2 (DLAC2) series on producing TAFs that meet the needs of the aviation community. In addition to providing information about tools for diagnosing winter weather and its related impacts, the module extends the Practically Perfect TAF (PPTAF) process to address an airportâs operational thresholds. By understanding the thresholds at airports for which they produce TAFs, forecasters will be better able to produce a PPTAF. The unit also examines how to communicate effectively the logic and uncertainty using the aviation forecast discussion (AvnFD) and addresses maintaining an effective TAF weather watch and updating the TAF proactively.

Comet

2009-09-22

297

GEM: Statistical weather forecasting procedure  

NASA Technical Reports Server (NTRS)

The objective of the Generalized Exponential Markov (GEM) Program was to develop a weather forecast guidance system that would: predict between 0 to 6 hours all elements in the airways observations; respond instantly to the latest observed conditions of the surface weather; process these observations at local sites on minicomputing equipment; exceed the accuracy of current persistence predictions at the shortest prediction of one hour and beyond; exceed the accuracy of current forecast model output statistics inside eight hours; and be capable of making predictions at one location for all locations where weather information is available.

Miller, R. G.

1983-01-01

298

Influence of Model Physics on NWP Forecasts  

NSDL National Science Digital Library

This module describes model parameterizations of sub-surface, boundary-layer,and free atmospheric processes, such as surface snow processes, soil characteristics, vegetation, evapotranspiration, PBL processes and parameterizations, and trace gases, and their interaction with the radiative transfer process. It specifically addresses how models treat these physical processes and how they can influence forecasts of sensible weather elements.

2007-07-17

299

FAWN: Florida Automated Weather Network  

NSDL National Science Digital Library

The Florida Automated Weather Network (FAWN) provides up-to-date weather information through a system of automated weather stations distributed throughout the State of Florida. Research scientists at the University of Florida work closely with extension agents to monitor the FAWN system and make sure it provides fast, reliable, and convenient access. Overall, there are four parts to the FAWN system: collecting data, transmitting it to the collection site, processing the data, and redistributing it to the end user. FAWN database servers maintained by IFAS Information Technologies receive weather data about the date and time of collection, the air temperature, soil temperature, relative humidity, dewpoint, rainfall, wind direction, wind speed, and radiation from remote stations every 15 minutes. The information is processed and made available almost instantaneously through several different search methods accessible through FAWN web server, as well as an interactive voice-response system.

300

Seasonal changes in physical processes controlling evaporation over inland water  

NASA Astrophysics Data System (ADS)

previous studies have shown the distinct characteristics of water surface energy fluxes in different seasons, much less analysis is conducted about how seasonal changes in physical processes and environmental variables in the atmospheric surface layer (ASL) cause variations in flux exchange. Here we analyzed and compared eddy covariance fluxes of sensible heat (H) and latent heat (LE) and other microclimate variables that were measured over a large inland water surface in the winter season (January, February, and March) and the summer season (June, July, and August) of 2008. Our analysis was primarily focused on LE using half-hour time series data on a short-term basis. Our results show that an increase in wind speeds (U) or vapor pressure difference in the ASL (?e) or ASL instability did not necessarily cause an increase in LE, and the opposite changes in LE with changes in these variables were observed. Relative regulations of LE by different environmental variables depended largely on ?e magnitudes. Under low ?e conditions, diurnal LE variations were not sensitive to changes in ?e and U but were controlled primarily by changes in the ASL stability. Under high ?e conditions, diurnal LE variations were mainly determined by changes in ?e, though alternate controls by U and ?e were observed, whereas ASL stability played minor roles in affecting LE variations. Whether these highly nonlinear responses of LE to environmental variables are adequately reflected in the bulk transfer relations requires further studies.

Zhang, Qianyu; Liu, Heping

2014-08-01

301

Introduction to statistical physics of media processes: Mediaphysics  

E-print Network

Processes of mass communications in complicated social or sociobiological systems such as marketing, economics, politics, animal populations, etc. as a subject for the special scientific discipline - "mediaphysics" - are considered in its relation with sociophysics. A new statistical physics approach to analyze these phenomena is proposed. A keystone of the approach is an analysis of population distribution between two or many alternatives: brands, political affiliations, or opinions. Relative distances between a state of a "person's mind" and the alternatives are measures of propensity to buy (to affiliate, or to have a certain opinion). The distribution of population by those relative distances is time dependent and affected by external (economic, social, marketing, natural) and internal (mean-field influential propagation of opinions, synergy effects, etc.) factors, considered as fields. Specifically, the interaction and opinion-influence field can be generalized to incorporate important elements of Ising-spin based sociophysical models and kinetic-equation ones. The distributions were described by a Schrodinger-type equation in terms of Green's functions. The developed approach has been applied to a real mass-media efficiency problem for a large company and generally demonstrated very good results despite low initial correlations of factors and the target variable.

Dmitri V. Kuznetsov; Igor Mandel

2005-06-29

302

The Process of Physics Teaching Assistants' Pedagogical Content Knowledge Development  

ERIC Educational Resources Information Center

This study explored the process of physics teaching assistants' (TAs) PCK development in the context of teaching a new undergraduate introductory physics course. "Matter and Interactions" (M&I) has recently adopted a new introductory physics course that focuses on the application of a small number of fundamental physical

Seung, Eulsun

2013-01-01

303

Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1  

E-print Network

Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1 Giacomo Mauro D) to a quantum computation? Can physics be simulated by a quantum computer? Do we believe that a quantum field on a quantum-digitalization of physics, with Quantum Theory as a special theory of information, and Physics

D'Ariano, Giacomo Mauro

304

Reconnaissance of Field Sites for the Study of Chemical Weathering on the Guayana Shield, South America  

SciTech Connect

Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic process level, the important controls on chemical weathering (physical erosion, temperature, precipitation) can be folded into larger scale models tracking the global carbon cycle. Our goal in this study was to carry out the preliminary work needed to establish a field research site for chemical weathering om the Cuayana Shield in South America. The Guayana Shield is a Precambrian province greater than 1.5 billion years old covering portions of Venezuela, Guyana (the country), Surinam, French Guiana, and Brazil (Figure 1). More important than the age of the rocks themselves, however, is the age of the erosion surface developed on the Shield, with estimates ranging as old as 65 million years. Preserved mostly in highlands, this very old erosion surface represents an end-member site where physical erosion has been significantly slower than the rate of chemical weathering. Much of the Shield is also noteworthy for the fact that chemical weathering is still occurring today, thus offering the chance to study a system in which a present day weathering regime is accompanied by an integrated weathering record over millions of years (Soler and Lasaga, 2000). If rates of chemical weathering can be determined for this very old weathering system where physical erosion is minor, they can then be compared with rates determined from sites with similar annual temperatures and rainfall, but much higher physical erosion rates. Comparative studies of this kind can provide a parameterization of chemical weathering rates as a function of physical erosion and tectonic uplift that can be used in global models for the carbon cycle.

Steefell, C I

2003-02-01

305

Weather information network including graphical display  

NASA Technical Reports Server (NTRS)

An apparatus for providing weather information onboard an aircraft includes a processor unit and a graphical user interface. The processor unit processes weather information after it is received onboard the aircraft from a ground-based source, and the graphical user interface provides a graphical presentation of the weather information to a user onboard the aircraft. Preferably, the graphical user interface includes one or more user-selectable options for graphically displaying at least one of convection information, turbulence information, icing information, weather satellite information, SIGMET information, significant weather prognosis information, and winds aloft information.

Leger, Daniel R. (Inventor); Burdon, David (Inventor); Son, Robert S. (Inventor); Martin, Kevin D. (Inventor); Harrison, John (Inventor); Hughes, Keith R. (Inventor)

2006-01-01

306

Salt weathering on Mars  

NASA Astrophysics Data System (ADS)

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974). However, irrespectively of the climatic environment a liquid brine is a necessity for salt induced fragmentation of rocks. If salt weathering is responsible for the fragmented rocks on the Martian surface it implies a temporary present of liquid H_2O. However, due to the present dry atmosphere on Mars brines can only be present in restricted places without being in equilibrium with the atmosphere (Clark and van Hart 1980). M. C. Malin (1974) JGR Vol 79,26 p 3888-3894 B. C. Clark and D. C. vanHart (1980) ICARUS 45, 370-378

Jagoutz, E.

307

Solar variability, weather, and climate  

NASA Technical Reports Server (NTRS)

Advances in the understanding of possible effects of solar variations on weather and climate are most likely to emerge by addressing the subject in terms of fundamental physical principles of atmospheric sciences and solar-terrestrial physis. The limits of variability of solar inputs to the atmosphere and the depth in the atmosphere to which these variations have significant effects are determined.

1982-01-01

308

Impact of Physical Attractiveness on Selection and Recruitment Process  

Microsoft Academic Search

The personality traits which include physical appearance in particular always matter once an organization goes for hiring new entrants. The principal point of this study is to comprehend the relationship of a candidate's physical appearance, qualification, dressing style, attractive communication skills, gender, and candidate’s photograph on resume with the hiring decision taken by a manager. The findings of this paper

Muhammad Imtiaz Subhani

2012-01-01

309

Framework for Understanding LENR Processes, Using Conventional Condensed Matter Physics  

Microsoft Academic Search

Conventional Condensed Matter physics provides a unifying framework for understanding Low Energy Nuclear Reactions (LENR's) in solids. In the paper, standard many-body physics techniques are used to illustrate this fact. Specifically, the paper shows that formally the theories by Schwinger, Hagelstein, and Chubb and Chubb (C&C), all can be related to a common set of equations, associated with reaction rate

Scott R. Chubb

310

Future Weather Station  

NSDL National Science Digital Library

In this activity students build dioramas of futuristic weather stations to demonstrate their knowledge of weather forecasting. They will work in groups to research modern forecasting equipment and techniques, and then build a weather station that will do something we cannot do at present (such as stopping tornadoes). They will present their dioramas and then discuss the pros and cons of controlling the weather.

311

Corridor Integrated Weather System  

Microsoft Academic Search

n Flight delays are now a major problem in the U.S. National Airspace System. A significant fraction of these delays are caused by reductions in en route capacity due to severe convective weather. The Corridor Integrated Weather System (CIWS) is a fully automated weather analysis and forecasting system designed to support the development and execution of convective weather impact mitigation

James E. Evans; Elizabeth R. Ducot

2006-01-01

312

Weather in Your Life.  

ERIC Educational Resources Information Center

Facts and activities related to weather and meteorology are presented in this unit. Separate sections cover the following topics: (1) the water cycle; (2) clouds; (3) the Beaufort Scale for rating the speed and force of wind; (4) the barometer; (5) weather prediction; (6) fall weather in Iowa (sleet, frost, and fog); (7) winter weather in Iowa…

Kannegieter, Sandy; Wirkler, Linda

313

Space Weather  

NASA Video Gallery

This lesson explores the origins, processes and risks associated with solar radiation including how it travels through the solar system, affects the Earthâ??s magnetosphere and poses a threat to as...

314

Simulation and Analysis of Physical Processes for Aiding Technology Development  

E-print Network

of Physics 1999 Presentations at several conferences, including NASA and international workshop at Harvard Funding from CIPA Metrology SPIE 2003, 1999 Applied Phys. Lett. 2002 IEEE Trans. Semi. Manufacturing

Cole, Dan C.

315

Framework for Understanding Lenr Processes, Using Conventional Condensed Matter Physics  

Microsoft Academic Search

Conventional condensed matter physics provides a unifying framework for understanding low-energy nuclear reactions (LENRs) in solids. In the paper, standard many-body physics techniques are used to illustrate this fact. Specifically, the paper shows that formally the theories by Schwinger, Hagelstein, and Chubb and Chubb (C&C), all can be related to a common set of equations, associated with reaction rate and

Scott R. Chubb

2006-01-01

316

Deeply weathered basement rocks in Norway  

NASA Astrophysics Data System (ADS)

Recent studies show that, in addition to tectonic processes, surface processes have also had a profound impact on the topography of Norway. This is especially obvious for the northernmost part of the Nordland county and for western Norway, where the current immature Alpine-type topography cannot be easily explained by tectonic processes only. Erosion of the sedimentary succession also does not seem sufficient to explain the observed relief. Common remnants of deeply weathered basement rocks, however, indicate a history of deep alteration and later erosion of the bedrock, which needs to be considered as another important factor in the development of the topographic relief. Most of the sites with deeply weathered basement exhibit a clay-poor grussy type of weathering, which is generally considered to be of relatively young age (Plio-/Pleistocene) and thought to represent an intermediate stage of weathering. Unfortunately, small amounts or complete absence of clay minerals in these weathering products precluded the accurate dating of this weathered material. Scandinavia was exposed to a large range of glaciations and the once extensive sedimentary successions have been almost entirely eroded, which impedes a minimum age estimate of the weathering profile. Although several sites preserving remnants of deep weathering can still be observed onshore Norway, they are all covered by Quaternary overburden and the age of the regolith remains thus unconstrained and a matter of debate. The only exception is a small Mesozoic basin on Andøya, northern Norway, where weathered and clay-poor saprolite was found underlying Jurassic and Cretaceous sedimentary rocks. Over the last few years the Geological Survey of Norway (NGU) has mapped and investigated deep weathering onshore Norway to better understand weathering processes and to constrain the age of the weathering remnants. The combined interpretation of geophysical, mineralogical and geochemical data, together with recent observations from the Norwegian shelf, where grussy type of weathered bedrock was found buried under Mesozoic sediments, leads to the conclusion that coarse-grained, clay-poor saprolite does not necessarily indicate a young age of weathering but could in fact be of Early Mesozoic age or even older. The Late Jurassic to Early Cretaceous faults in the Lofoten-Vesterålen area are for instance little affected by weathering processes. With the goal to refine our understanding of the complex weathering processes and to constrain them in time, the NGU is establishing a new K-Ar laboratory for the dating and characterization of illite grown authigenically in the saprolites. It is expected that the data generated therein will contribute new quantitative constraints to the long-lasting debate as to the age of weathering processes in Scandinavia.

Bönner, Marco; Knies, Jochen; Fredin, Ola; Olesen, Odleiv; Viola, Giulio

2014-05-01

317

Exploratory Observations of Physical Processes in the upper Sulu Sea  

NASA Astrophysics Data System (ADS)

The Sulu Sea extends roughly 600 km in all directions, is up to 5 km deep, and is connected to the Pacific Ocean, but only via surrounding seas through several straits of varying width and depth. The Dipolog Strait between the Philippine islands of Mindanao and Negros connects the Sulu to the Bohol Sea. Straits between the islands of Panay, Palawan and Borneo connect the Sulu to the South China Sea. Straits between Borneo and Mindanao connect the Sulu to the Sulawesi Sea. External interactions with the Sulu Sea include strait currents, monsoon wind stress, tides and internal waves propagating into the sea from the perimeter. Mooring observations indicate large intraseasonal signals in currents through the Dipolog Strait and the Cuyo East Passage, west of Panay. Known impacts on the Sulu thus have timescales ranging from a day to a year. Currents through the boundary straits reverse direction with depth and so have a complex interaction with the Sulu Sea. To explore physical processes in the Sulu Sea, four in situ surveys were conducted between June 2007 and March 2009 during the Philippines Straits Dynamics Experiment (PhilEx). Observations collected include current from hull-mounted Doppler sonar and temperature, salinity, dissolved oxygen and fluorescence from station casts and underway surface measurements. Horizontal shear dominates the surface current pattern. The shear’s horizontal scales are small compared to the Sulu Sea’s dimensions. The surface water also has significant density fronts at scales similar to the horizontal shear. This horizontal structure is described by viewing observed properties on maps and as a function of along-track position. Horizontal structure is quantified by computing basic statistics along-track and through spectral and wavelet analysis. A topic investigated is the relative role of boundary strait current variability and wind forcing in generating the observed horizontal shear and density fronts. When currents directed into the Sulu are stronger, more energy could be available for eddies in the sea and these eddies could have sizes related to strait dimensions. Sulu Sea water is traced to sources in boundary straits. One example is relatively warm and fresh surface water which appears to come from the Balabac Strait between Palawan and Borneo. A broader horizontal picture of the Sulu Sea is established by using remote sensing and numerical model output.

Martin, J. P.; Gordon, A. L.

2010-12-01

318

Australian Severe Weather  

NSDL National Science Digital Library

The Australian Severe Weather Web site is maintained by self proclaimed severe weather enthusiasts Michael Bath and Jimmy Deguara. Other weatherphobes will fully appreciate what the authors have assembled. Everything from weather images, storm news, tropical cyclone data, bush fire and wild fire information, weather observation techniques, and even video clips and Web cam links. Although these other items make the site well rounded, the extensive amount of categorized weather pictures (which are quite extraordinary) are reason enough to visit.

319

What's the Weather?  

NSDL National Science Digital Library

In this lesson, students use daily observations, videos, and activities to learn about meteorology and the changing nature of weather. They will also identify weather events that are commonly reported in the news and discuss how weather affects lives. They should understand that weather can change daily and weather patterns change over the seasons, and that it has characteristics that can be measured and predicted. Suggestions for an optional field trip are also provided.

2005-01-01

320

Cracks in desert pavement rocks: Further insights into mechanical weathering by directional insolation  

E-print Network

Cracks in desert pavement rocks: Further insights into mechanical weathering by directional August 2010 Keywords: Desert pavements Physical weathering Desert geomorphology Insolation weathering Fractures The formation of cracks is a fundamental first step in the physical weathering of rocks in desert

Ahmad, Sajjad

321

Influence of aerosols on weather conditions  

NASA Astrophysics Data System (ADS)

The accurate numerical weather prediction demands the better understanding and detailed representation of aerosol effects in the atmosphere. The presence of various types of aerosols as well as other chemical components in the atmosphere causes different effects on weather, climate and still keeps many unresolved aspects. Non-linear interactions between weather phenomena, in particular, precipitation and aerosols need to be additionally highlighted. To investigate features of the atmosphere sensitivity to aerosols the high resolution limited area model Harmonie (Hirlam Aladin Regional/Meso-scale Operational NWP In Europe) was used. The Harmonie is extensively developing weather forecast modeling system, in which the convection-permitting physics substantially promotes to the near-realistic representation of the aerosol effects complexity. Numerical experiments with modifications in aerosol concentrations were performed over the Finland domain. The direct effect of aerosols associates with changes in both radiation processes and precipitation formation. The presence of aerosols increases cloud drop concentration and reduces the effective drop size. A high density of nuclei population initializes coalescence growth, accelerates precipitation formation, increases cloud lifetime and lags precipitation. Since aerosols disperse and absorb the radiation they have a direct effect on the albedo, which depends on the aerosol type. The land aerosols increase the albedo mainly in the lower atmospheric layers. Higher up, the effect of land aerosols on the shortwave radiation coming down toward the surface is diminished in comparison with aerosols of the marine origin. The high concentrations of continental aerosols lead to changes in the precipitation rate, while sea aerosols mainly cause the displacement in time of the precipitation event.

Palamarchuk, Iuliia; Stepanenko, Sergiy; Ivanov, Sergiy; Ruban, Igor; Pavlova, Hanna

2014-05-01

322

Student Understanding Of The Physics And Mathematics Of Process Variables In P-V Diagrams  

E-print Network

Student Understanding Of The Physics And Mathematics Of Process Variables In P-V Diagrams Evan B on the paired questions shows evidence of isolated understanding of physics and mathematics. Some difficulties may affect understanding of physics concepts in thermodynamics. We have presented results

Maine, University of

323

Weather Camp 2012 "Weather and Climate All Around Us"  

E-print Network

Weather Camp 2012 "Weather and Climate All Around Us" Are you interested in the weather? Come to Weather Camp at UNL What is Weather Camp? For more information Weather camp is a week long day camp for students who will be 11-14 years old at the time of the camp Most of the activities at Weather Camp 2012

Farritor, Shane

324

Structural and physical modifications of corn biscuits during baking process  

Microsoft Academic Search

Colour, crust browning and specific volume of batter is essential to the manufacture of biscuit of good quality, but these properties are rarely measured directly in fermenting batter due to lack of suitable instrumentation. The aim of this study was to systematically evaluate the changes in quality parameters and physical properties of corn biscuits during baking in real time and

E. Lara; P. Cortés; V. Briones; M. Perez

2011-01-01

325

Process physics determining 2-D impurity profiles in VLSI devices  

Microsoft Academic Search

Physically robust diffusion models are required to simulate two-dimensional (2D) impurity profiles in VLSI devices. The accuracy of the initial dopant profiles severely limits the predictive capability of 2D device simulators. Historically, the most successful diffusion models have been based on point defect mechanisms involving either vacancy or in terstitial assisted diffusion. It is clear that the local con centration

P. B. Griffin; J. D. Plummer

1986-01-01

326

Modeling and control of physical processes using proper orthogonal decomposition  

Microsoft Academic Search

The proper orthogonal decomposition (POD) technique (or the Karhunan Loève procedure) has been used to obtain low-dimensional dynamical models of many applications in engineering and science. In principle, the idea is to start with an ensemble of data, called snapshots, collected from an experiment or a numerical procedure of a physical system. The POD technique is then used to produce

Hung V. Ly; Hien T. Tran

2001-01-01

327

Modelling Topological and Metrical Properties in Physical Processes  

Microsoft Academic Search

Developing suitable representations for formalisingnon-trivial domain knowledge has always been centralto AI. Within Naive Physics ie. the task ofencoding experiential knowledge of the world, fewformal theories have appeared that exhibit formalelegance, conciseness and generality to cover a widevariety of modelling problems. We outline a firstorder formalism being developed that meets thesecriteria. The formalism is particularly attractive inthat it provides the

David A. Randell; Anthony G. Cohn

1989-01-01

328

Continuous Cable Processing by the Physical Vapor Deposition Technique.  

National Technical Information Service (NTIS)

A continuous cable processor (CCP) has been designed, built and tested to deposit aluminum or copper on 70-mm-wide polyimide film by the physical vapor deposited film can be better than 2%. Various equipment difficulties resulted in deposited films with t...

G. J. Hale

1983-01-01

329

Distribution of colluvia and saprolites and their physical properties in a zero-order basin in Okinawa, southwestern Japan  

Microsoft Academic Search

The thickness and physical properties of colluvium and saprolite were investigated to clarify their role in the hydrological processes in a forested basin. We measured their thickness using a handy dynamic cone penetrometer, and surveyed soil profiles to obtain undisturbed cylindrical samples for measuring physical properties, i.e., effective porosity. Saprolite is divided into strongly weathered saprolite and weakly weathered saprolite

Yasuhiro Ohnuki; Ryuichi Terazono; Hitoshi Ikuzawa; Isao Hirata; Kensaku Kanna; Hirokatsu Utagawa

1997-01-01

330

Flight Deck Weather Avoidance Decision Support: Implementation and Evaluation  

NASA Technical Reports Server (NTRS)

Weather related disruptions account for seventy percent of the delays in the National Airspace System (NAS). A key component in the weather plan of the Next Generation of Air Transportation System (NextGen) is to assimilate observed weather information and probabilistic forecasts into the decision process of flight crews and air traffic controllers. In this research we explore supporting flight crew weather decision making through the development of a flight deck predicted weather display system that utilizes weather predictions generated by ground-based radar. This system integrates and presents this weather information, together with in-flight trajectory modification tools, within a cockpit display of traffic information (CDTI) prototype. that the CDTI features 2D and perspective 3D visualization models of weather. The weather forecast products that we implemented were the Corridor Integrated Weather System (CIWS) and the Convective Weather Avoidance Model (CWAM), both developed by MIT Lincoln Lab. We evaluated the use of CIWS and CWAM for flight deck weather avoidance in two part-task experiments. Experiment 1 compared pilots' en route weather avoidance performance in four weather information conditions that differed in the type and amount of predicted forecast (CIWS current weather only, CIWS current and historical weather, CIWS current and forecast weather, CIWS current and forecast weather and CWAM predictions). Experiment 2 compared the use of perspective 3D and 21/2D presentations of weather for flight deck weather avoidance. Results showed that pilots could take advantage of longer range predicted weather forecasts in performing en route weather avoidance but more research will be needed to determine what combinations of information are optimal and how best to present them.

Wu, Shu-Chieh; Luna, Rocio; Johnson, Walter W.

2013-01-01

331

The lithium, boron and strontium isotopic systematics of groundwaters from an arid aquifer system: Implications for recharge and weathering processes  

NASA Astrophysics Data System (ADS)

Saline groundwaters are common to inland Australia, but their hydrochemical evolution and origin remain largely unknown. The saline groundwaters in the alluvial aquifers of the Darling River have previously been found to exhibit broad similarity in traditional hydrochemical and isotopic tracers. By contrast, in this study the trace element isotopes (?7Li, ?11B and 87Sr/86Sr) have illuminated more complex hydrogeochemical processes in the same aquifer system. This paper reports the first ever set of ?7Li values in any groundwater system in Australia. They varied from +5.8 to +16.2 with an average value of +9.7‰ (n = 19) in the alluvial aquifers of the Darling River catchment. The ?11B values were all higher than seawater and close to some of the highest ?11B values ever reported in the literature for a groundwater system (+44.4 to +53.9; average: +48.8, n = 17). The 87Sr/86Sr ratios ranged from 0.708 to 0.713, with an average value of 0.709 (n = 19). The differing signatures in these trace element isotope values, highlighted by discovery of the deeper older groundwater system with heavier Li isotope values and higher 87Sr/86Sr, is an important finding of this research. Simple mixing models between river water and saline groundwater cannot explain the observed variation in trace element isotopes. Hydrochemical evolution was found to be dependent on proximity to the Darling River and depth. Varying degrees of Li and B isotopic fractionation during water-sediment interaction were interpreted to account for the evolution of the saline groundwaters. The measurement of these trace element isotopes has permitted delineation of groundwater end-members that would have otherwise not been identified; in their absence an inaccurate interpretation of the hydrochemical evolution of these saline groundwaters would have been made. This study highlights the importance of a multi-tracer approach, which includes trace element isotopes, in resolving complex geochemical processes in groundwater in semi-arid to arid zone environments.

Meredith, Karina; Moriguti, Takuya; Tomascak, Paul; Hollins, Suzanne; Nakamura, Eizo

2013-07-01

332

Interactive Weather Information Network  

NSDL National Science Digital Library

Offered by the National Oceanic and Atmospheric Administration (NOAA), the Interactive Weather Information Network (IWIN) is a collection of interactive weather maps and satellite images that is updated every five seconds. Visitors can see cloud cover animation loops, NEXRAD Radar images of precipitation, a map of all current weather fronts, and an interactive national map to see information about any particular state. Other information on the site includes a listing of any active weather warnings, a link for world weather data, and more, making this a must-see site for all those users interested in the most current weather happenings anywhere.

2002-01-01

333

Pilot weather advisor  

NASA Technical Reports Server (NTRS)

The results of the work performed by ViGYAN, Inc., to demonstrate the Pilot Weather Advisor cockpit weather data system using a broadcast satellite communication system are presented. The Pilot Weather Advisor demonstrated that the technical problems involved with transmitting significant amount of weather data to an aircraft in-flight or on-the-ground via satellite are solvable with today's technology. The Pilot Weather Advisor appears to be a viable solution for providing accurate and timely weather information for general aviation aircraft.

Kilgore, W. A.; Seth, S.; Crabill, N. L.; Shipley, S. T.; Graffman, I.; Oneill, J.

1992-01-01

334

Edheads: Weather Activities  

NSDL National Science Digital Library

This great interactive resource allows you multiple opportunities to explore weather related concepts. After clicking start, you will learn how to report and predict the weather at the underground W.H.E.D weather caves! Each activity has three different levels, and each level is harder than the one before it. This resource also includes a teacher's guide (with pre- and post- tests) and links to additional weather related resources. These include a weather glossary, a Fahrenheit to Celsius & Celsius to Fahrenheit converter, and a link that provides information about interesting people in the weather field.

2010-01-01

335

CHEMICAL AND PHYSICAL PROCESSING OF PRESOLAR MATERIALS IN THE SOLAR NEBULA AND THE IMPLICATIONS FOR  

E-print Network

CHEMICAL AND PHYSICAL PROCESSING OF PRESOLAR MATERIALS IN THE SOLAR NEBULA AND THE IMPLICATIONS and physical processes in the outer solar nebula are reviewed. It is argued that the outer nebula of presolar versus nebular dominance in the outer solar nebula and of how to distinguish interstellar

Fegley Jr., Bruce

336

Bio-Optical Response and Coupling with Physical Processes in the Lombok Strait Region  

E-print Network

properties with the dominant physical processes in the region, to provide information about the coupling relatively little optical data exist. 2. The coupling of bio-optical properties with the physical processes. The contribution of dissolved and particulate matter to in-water optical properties and their effect on ocean color

Boss, Emmanuel S.

337

Modeling and Control of Physical Processes using Proper Orthogonal Decomposition  

Microsoft Academic Search

Proper orthogonal decomposition (POD) technique (or the Karhunan Lo`eve procedure)has been used to obtain low dimensional dynamical models of many applications in engineeringand science. In principle, the idea is to start with an ensemble of data, calledsnapshots, collected from an experiment or a numerical procedure of a physical system. ThePOD technique is then used to produce a set of basis

Hung V. Ly; Hien T. Tran

1999-01-01

338

Adaptive, maladaptive, mediational, and bidirectional processes of relational and physical aggression, relational and physical victimization, and peer liking.  

PubMed

A three-wave longitudinal study among ethnically diverse preadolescents (N?=?597 at Time 1, ages 9-11) was conducted to examine adaptive, maladaptive, mediational, and bidirectional processes of relational and physical aggression, victimization, and peer liking indexed by peer acceptance and friendships. A series of nested structural equation models tested the hypothesized links among these peer-domain factors. It was hypothesized that (1) relational aggression trails both adaptive and maladaptive processes, linking to more peer victimization and more peer liking, whereas physical aggression is maladaptive, resulting in more peer victimization and less peer liking; (2) physical and relational victimization is maladaptive, relating to more aggression and less peer liking; (3) peer liking may be the social context that promotes relational aggression (not physical aggression), whereas peer liking may protect against peer victimization, regardless of its type; and (4) peer liking mediates the link between forms of aggression and forms of peer victimization. Results showed that higher levels of peer liking predicted relative increases in relational aggression (not physical aggression), which in turn led to more peer liking. On the other hand, more peer liking was predictive of relative decreases in relational aggression and relational victimization in transition to the next grade (i.e., fifth grade). In addition, relational victimization predicted relative increases in relational aggression and relative decreases in peer liking. Similarly, physical aggression was consistently and concurrently associated more physical victimization and was marginally predictive of relative increases in physical victimization in transition to the next grade. More peer liking predicted relative decreases in physical victimization, which resulted in lower levels of peer liking. The directionality and magnitude of these paths did not differ between boys and girls. PMID:24318459

Kawabata, Yoshito; Tseng, Wan-Ling; Crick, Nicki R

2014-01-01

339

s-process nucleosynthesis-nuclear physics and the classical model  

Microsoft Academic Search

Among the various processes responsible for the formation of the heavy elements in stars, the slow neutron capture process (s-process) is distinguished by the fact that it involves mostly stable isotopes. Therefore, the relevant nuclear physics data can be determined by experiments. With this rather reliable data basis, s-process nucleosynthesis offers an important testground of models for the late stages

F. Kappeler; H. Beer; K. Wisshak

1989-01-01

340

Evidence of Space Weathering in Regolith Breccias II: Asteroidal Regolith Breccias  

NASA Technical Reports Server (NTRS)

Space weathering products, such as agglutinates and nanophaase iron-bearing rims are easily preserved through lithifcation in lunar regolith breccias, thus such products, if produced, should be preserved in asteroidal regotith breccias as well. A study of representative regolith breecia meteorites, Fayetteville (H4) and Kapoeta (howardite), was undertaken to search for physical evidence of space weathering on asteroids. Amorphous or npFe(sup 0)-bearing rim cannot be positively identified in Fayetteville, although possible glass rims were found. Extensive friction melt was discovered in the meteorite that is difficult to differentiate from weathered materials. Several melt products, including spherules and agglutinates, as well as one irradiated rim and one possible npFe(sup 0)-bearing rim were identified in Kapoeta. The existence of these products suggests that lunar-like space weathering processes are, or have been, active on asteroids.

Noble, Sarah K.; Keller, Lindsay P.; Pieters, Carle M.

2011-01-01

341

On Observing the Weather  

NSDL National Science Digital Library

In this article, Mount Washington Observatory meteorologist Tim Markle shares the ins and outs of his daily weather-observing routine and offers insights on making weather observations at home or at school.

Crane, Peter

2004-05-01

342

Owlie Skywarn's Weather Book  

NSDL National Science Digital Library

This is an online activity book from the National Weather Service that teaches about hazardous weather. The site also includes links to kids sites for the Federal Emergency Management Agency (FEMA) and the National Oceanic and Atmospheric Agency (NOAA).

Garcia, Cris; Davis, Steve

2001-06-22

343

Weather in Antarctica  

NSDL National Science Digital Library

This homepage includes information about the weather in Antarctica and links to pages on the climate, wind chill, clouds, snow and ice, and pressure and storms of Antarctica. The current weather conditions updated automatically at various stations are also provided.

Hutchings, Thomas

1998-01-01

344

Winter Weather Emergencies  

MedlinePLUS

Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

345

CLARA: A Contemporary Approach to Physics Data Processing  

E-print Network

where data processing algorithms filter continuously flowing data. In CLARA's domain of loosely coupled. This system allows users to design (Java, C++, and Python languages are supported) and deploy data

Gilfoyle, Jerry

346

Framework for Understanding LENR Processes, Using Ordinary Condensed Matter Physics  

Microsoft Academic Search

As I have emphasized ootnotetextS.R. Chubb, Proc. ICCF10 (in press). Also, http:\\/\\/www.lenr-canr.org\\/acrobat\\/ChubbSRnutsandbol.pdf http:\\/\\/www.lenr-canr.org\\/acrobat\\/ChubbSRnutsandbol.pdf, S.R. Chubb, Trans. Amer. Nuc. Soc. 88 , 618 (2003)., in discussions of Low Energy Nuclear Reactions(LENRs), mainstream many-body physics ideas have been largely ignored. A key point is that in condensed matter, delocalized, wave-like effects can allow large amounts of momentum to be transferred instantly to

Scott Chubb

2005-01-01

347

Time delayed processes in physics, biophysics and archaeology  

E-print Network

The motion of particles, where the particles: electrons, ions in microtubules or migrated peoples can be described as the superposition of diffusion and ordered waves. In this paper it is shown that the master equation for transport processes can be formulated as the time delayed hyperbolic partial equation. The equation describes the processes with memory. For characteristic times shorter than the relaxation time the master equation is the generalized Klein - Gordon equation. Key words: hyperbolic transport, microtubules, heat waves, Neolithic migration

Magdalena Anna Pelc

2007-05-31

348

Weather Camp 2012: Weather and Climate All Around Us Are you interested in the weather?  

E-print Network

Weather Camp 2012: Weather and Climate All Around Us Are you interested in the weather? Come to Weather Camp at UNL! What is Weather Camp? For more information Weather camp is a week-long day camp for students who will be 11-14 years old at the time of the camp. Most of the activities at Weather Camp 2012

Farritor, Shane

349

Stormfax Weather Services  

NSDL National Science Digital Library

This site offers links to a variety of weather information, including national, international and local weather maps and forecasts, satellite and radar imagery, and severe weather warnings. There are also links to diverse resources such as fire maps, glacier inventories, snow depths, storm surges and tropical storms. There are reports and advisories about El Nino and La Nina. The site also has a glossary of weather terms and conversion charts for temperature, wind speed and atmospheric pressure.

2002-06-10

350

Enviropedia: Introduction to Weather  

NSDL National Science Digital Library

This resource provides an overview of weather, the day-to-day changes in temperature, air pressure, moisture, wind, cloudiness, rainfall and sunshine. Links embedded in the text provide access to descriptions of cloud types and to information on weather hazards such as fog, hurricanes, thunderstorms, and tornadoes. Other topics include meteorology, weather measurements, and weather mapping. Materials are also provided on the water cycle and its elements, such as evaporation, uplift and cooling of air, dew point, condensation, and precipitation.

2007-12-12

351

Fire Weather Climatology  

NSDL National Science Digital Library

The âFire Weather Climatologyâ module provides a comprehensive look at fire regions across the United States and characteristics of typical fire seasons in each region. In addition, critical fire weather patterns are described in terms of their development, duration and impact on fire weather. Numerous case studies provide examples and opportunities to practice recognizing these critical patterns and how they can affect fire ignition and spread. This module is part of the Advanced Fire Weather Forecasters Course.

Comet

2008-04-28

352

Space Weathering Agent: Solar Wind  

NASA Astrophysics Data System (ADS)

In the vacuum of space, the interactions of energetic particles with the surfaces of airless planetary bodies cause radiation damage, chemical changes, optical changes, erosional sputtering, and heat. This is an essential part of the process called space weathering. A group at the Laboratory for Atomic and Surface Physics at the University of Virginia specialize in experiments, among other things, where they bombard surfaces with charged particles to see what happens. Recent work by Mark Loeffler, Cathy Dukes, and Raul Baragiola focused on what happens to olivine mineral grains when they are irradiated by helium ions to better understand the effects of solar wind on the surface composition and, therefore, appearance of asteroids. Their experiments were the first to measure chemical and reflectance changes in olivine before and after irradiation while still under vacuum conditions. The resulting changes in the reflectance spectra of olivine slabs and powders are directly correlated with the formation of metallic iron in the very outer surface of the mineral grains.

Martel, L. M. V.

2009-08-01

353

Weather Theory Introduction  

E-print Network

11-1 Weather Theory Chapter 11 Introduction Weather is an important factor that influences aircraft), visibility (clearness or cloudiness), and barometric pressure (high or low). The term weather can also apply of the atmosphere. Atmosphere The atmosphere is a blanket of air made up of a mixture of gases that surrounds

354

American Weather Stories.  

ERIC Educational Resources Information Center

Weather has shaped United States' culture, national character and folklore; at times it has changed the course of history. The seven accounts compiled in this publication highlight some of the nation's weather experiences from the hurricanes that threatened Christopher Columbus to the peculiar run of bad weather that has plagued American…

Hughes, Patrick

355

Predicting Seasonal Weather  

NSDL National Science Digital Library

This module is about a new method of predicting seasonal weather. The site describes the effects of El Nino on global weather and the accuracy of the new model. It includes links to classroom resources for a variety of weather-based units.

Dybas, Cheryl

2008-12-07

356

Extreme Weather on Earth  

NSDL National Science Digital Library

In this activity, students utilize a set of photographs and a 30 minute video on weather to investigate extreme weather events. They are posed with a series of questions that ask them to identify conditions predictive of these events, and record them on a worksheet. Climate and weather concepts defined.

Mika, Anna; Education, National G.

357

Space Weather Now  

NSDL National Science Digital Library

The Space Weather Now page is intended to give the non-technical user a "plain language" look at space weather. It includes information about relevant events and announcements, data from and about different instruments and satellites watching various aspects of space weather, alerts and advisories, daily themes of products and services, and links appropriate for the various groups of users.

Center, Space E.; Service, National O.

358

Climate and Weather  

NSDL National Science Digital Library

This video discusses the differences between climate and weather by defining and presenting examples of each. When presenting examples of weather, the video focuses on severe events and how meteorologists predict and study the weather using measurement, satellites, and radar. The climate focus is primarily on an overview of climate zones.

Geographic, National

359

METEOROLOGICAL Weather and Forecasting  

E-print Network

AMERICAN METEOROLOGICAL SOCIETY Weather and Forecasting EARLY ONLINE RELEASE This is a preliminary and interpretation of information from National Weather Service watches and warnings by10 decision makers such an outlier to the regional severe weather climatology. An analysis of the synoptic and13 mesoscale

360

Winter Weather Introduction  

E-print Network

Winter Weather Management #12;Introduction · Campus Facilities Staff · Other Campus Organizations #12;Purpose · Organize and coordinate the campus response to winter weather events to maintain campus for use by 7 AM. · Response will be modified depending upon forecast and current weather conditions. #12

Taylor, Jerry

361

Intelligent weather agent for aircraft severe weather avoidance  

E-print Network

avoidance capability has increased. In this thesis, an intelligent weather agent is developed for general aviation aircraft. Using a radar image from an onboard weather radar, the intelligent weather agent determines the safest path around severe weather...

Bokadia, Sangeeta

2012-06-07

362

Convective Weather Avoidance with Uncertain Weather Forecasts  

NASA Technical Reports Server (NTRS)

Convective weather events have a disruptive impact on air traffic both in terminal area and in en-route airspaces. In order to make sure that the national air transportation system is safe and efficient, it is essential to respond to convective weather events effectively. Traffic flow control initiatives in response to convective weather include ground delay, airborne delay, miles-in-trail restrictions as well as tactical and strategic rerouting. The rerouting initiatives can potentially increase traffic density and complexity in regions neighboring the convective weather activity. There is a need to perform rerouting in an intelligent and efficient way such that the disruptive effects of rerouting are minimized. An important area of research is to study the interaction of in-flight rerouting with traffic congestion or complexity and developing methods that quantitatively measure this interaction. Furthermore, it is necessary to find rerouting solutions that account for uncertainties in weather forecasts. These are important steps toward managing complexity during rerouting operations, and the paper is motivated by these research questions. An automated system is developed for rerouting air traffic in order to avoid convective weather regions during the 20- minute - 2-hour time horizon. Such a system is envisioned to work in concert with separation assurance (0 - 20-minute time horizon), and longer term air traffic management (2-hours and beyond) to provide a more comprehensive solution to complexity and safety management. In this study, weather is dynamic and uncertain; it is represented as regions of airspace that pilots are likely to avoid. Algorithms are implemented in an air traffic simulation environment to support the research study. The algorithms used are deterministic but periodically revise reroutes to account for weather forecast updates. In contrast to previous studies, in this study convective weather is represented as regions of airspace that pilots are likely to avoid. The automated system periodically updates forecasts and reassesses rerouting decisions in order to account for changing weather predictions. The main objectives are to reroute flights to avoid convective weather regions and determine the resulting complexity due to rerouting. The eventual goal is to control and reduce complexity while rerouting flights during the 20 minute - 2 hour planning period. A three-hour simulation is conducted using 4800 flights in the national airspace. The study compares several metrics against a baseline scenario using the same traffic and weather but with rerouting disabled. The results show that rerouting can have a negative impact on congestion in some sectors, as expected. The rerouting system provides accurate measurements of the resulting complexity in the congested sectors. Furthermore, although rerouting is performed only in the 20-minute - 2-hour range, it results in a 30% reduction in encounters with nowcast weather polygons (100% being the ideal for perfectly predictable and accurate weather). In the simulations, rerouting was performed for the 20-minute - 2-hour flight time horizon, and for the en-route segment of air traffic. The implementation uses CWAM, a set of polygons that represent probabilities of pilot deviation around weather. The algorithms were implemented in a software-based air traffic simulation system. Initial results of the system's performance and effectiveness were encouraging. Simulation results showed that when flights were rerouted in the 20-minute - 2-hour flight time horizon of air traffic, there were fewer weather encounters in the first 20 minutes than for flights that were not rerouted. Some preliminary results were also obtained that showed that rerouting will also increase complexity. More simulations will be conducted in order to report conclusive results on the effects of rerouting on complexity. Thus, the use of the 20-minute - 2-hour flight time horizon weather avoidance teniques performed in the simulation is expected to provide benefits for short-term weather avoidan

Karahan, Sinan; Windhorst, Robert D.

2009-01-01

363

Controls on chemical weathering kinetics: Implications from modelling of stable isotope fractionations  

NASA Astrophysics Data System (ADS)

The kinetic controls on silicate chemical weathering rates are thought central to the feedback process that regulates global climate on geological time scales. However the nature and magnitude of these kinetic controls are controversial. In particular the importance of physical erosion rates is uncertain with some arguing that there is an upper limit on chemical weathering fluxes irrespective of physical erosion rates (e.g. Dixon and von Blackenburg, 2012). Others argue that it is the hydrology of catchments which determines flow path lengths and fluid residence times which are critical to chemical weathering fluxes (e.g. Maher, 2011). Understanding these physical controls is essential to predicting how chemical weathering fluxes will respond the key climatic controls. Chemical weathering fluxes are best estimated by the integrated riverine outputs from catchments as soil profiles may not integrate all the flow paths. However the interpretation of chemical weathering processes based solely on flux data is difficult, because of both the multiple processes acting and multiple phases dissolving that contribute to these fluxes. Fractionations of stable isotopes of the soluble elements including Li, Mg, Si and Ca should place additional constraints on chemical weathering processes. Here we use a simple reactive-transport model to interpret stable isotope fractionations. Although still a simplification of the natural system, this offers a much closer representation than simple batch and Rayleigh models. The isotopic fractionations are shown to be a function of the ratio of the amount of the element supplied by mineral dissolution to that lost to secondary mineral formation and the extent of reaction down the flow path. The modelling is used to interpret the evolution of dissolved Li, Mg and Si-isotope ratios in Ganges river system. The evolution of Si isotopic ratios in the rapidly eroding Himalayan catchments is distinct from that in the flood planes. Critically the extent of the isotopic fractionations is a measure of the approach of the system to chemical equilibrium, a key indicator of the temperature sensitivity of the chemical weathering rate and hence important to understanding the climate-weathering feedback. Dixon JL, & von Blanckenburg, F, (2012) Soils as pacemakers and limiters of global silicate weathering. Comptes Rendus Geoscience, 344:597-609. Maher, K (2011) The role of fluid residence time and topographic scales in determining chemical fluxes from landscapes. Earth and Planetary Science Letters, 312:48-58.

Bickle, M. J.; Tipper, E.; De La Rocha, C. L.; Galy, A.; Li, S.

2013-12-01

364

Relativity Based on Physical Processes Rather Than Space-Time  

NASA Astrophysics Data System (ADS)

Physicists' understanding of relativity and the way it is handled is at present dominated by the interpretation of Albert Einstein, who related relativity to specific properties of space and time. The principal alternative to Einstein's interpretation is based on a concept proposed by Hendrik A. Lorentz, which uses knowledge of classical physics to explain relativistic phenomena. In this paper, we will show that on the one hand the Lorentz-based interpretation provides a simpler mathematical way of arriving at the known results for both Special and General Relativity. On the other hand, it is able to solve problems which have remained open to this day. Furthermore, a particle model will be presented, based on Lorentzian relativity, which explains the origin of mass without the use of the Higgs mechanism, based on the finiteness of the speed of light, and which provides the classical results for particle properties that are currently only accessible through quantum mechanics.

Giese, Albrecht

2013-09-01

365

Asteroids: Does Space Weathering Matter?  

NASA Technical Reports Server (NTRS)

The interpretive calibrations and methodologies used to extract mineralogy from asteroidal spectra appear to remain valid until the space weathering process is advanced to a degree which appears to be rare or absent on asteroid surfaces. Additional information is contained in the original extended abstract.

Gaffey, Michael J.

2001-01-01

366

Radiation induced physical and chemical processes in zeolite materials  

Microsoft Academic Search

Ionic processes induced by high energy radiation in zeolites, including electron and hole trapping and related chemical reactions, are reviewed in this paper. Electronic structures of electrons localized in clusters of charge balancing cations and those solvated in zeolite confined water clusters are characterized by a combination of spectroscopic techniques such as ESR and transient UV–visible absorption. Reactivities of these

Guohong Zhang; Xinsheng Liu; J. Kerry Thomas

1997-01-01

367

Chemical weathering and CO? consumption in the Lower Mekong River.  

PubMed

Data on river water quality from 42 monitoring stations in the Lower Mekong Basin obtained during the period 1972-1996 was used to relate solute fluxes with controlling factors such as chemical weathering processes. The total dissolved solid (TDS) concentration of the Lower Mekong varied from 53 mg/L to 198 mg/L, and the median (114 mg/L) was compared to the world spatial median value (127 mg/L). Total cationic exchange capacity (Tz(+)) ranged from 729 to 2,607 ?molc/L, and the mean (1,572 ?molc/L) was 1.4 times higher than the world discharge-weighted average. Calcium and bicarbonate dominated the annual ionic composition, accounting for ~70% of the solute load that equalled 41.2×10(9)kg/y. TDS and major elements varied seasonally and in a predictable way with river runoff. The chemical weathering rate of 37.7t/(km(2)y), with respective carbonate and silicate weathering rates of 27.5t/(km(2) y) (13.8mm/ky) and 10.2t/(km(2) y) (3.8mm/ky), was 1.5 times higher than the global average. The CO2 consumption rate was estimated at 191×10(3)molCO2/(km(2)y) for silicate weathering, and 286×10(3)molCO2/(km(2)y) by carbonate weathering. In total, the Mekong basin consumed 228×10(9)molCO2/y and 152×10(9)molCO2/y by the combined weathering of carbonate and silicate, constituting 1.85% of the global CO2 consumption by carbonate weathering and 1.75% by silicates. This is marginally higher than its contribution to global water discharge ~1.3% and much higher than (more than three-fold) its contribution to world land surface area. Remarkable CO2 consumed by chemical weathering (380×10(9)mol/y) was similar in magnitude to dissolved inorganic carbon as HCO3(-) (370×10(9)mol/y) exported by the Mekong to the South China Sea. In this landscape, atmospheric CO2 consumption by rock chemical weathering represents an important carbon sink with runoff and physical erosion controlling chemical erosion. PMID:24291559

Li, Siyue; Lu, X X; Bush, Richard T

2014-02-15

368

External Resource: Weathering and Erosion  

NSDL National Science Digital Library

This activity includes background information about weathering, as well as simple demonstrations/activities to model how weather conditions contribute to weathering and erosion. Topics include: chemical weathering, dunes, erosion, floods, glaciers, physi

1900-01-01

369

Control of physical properties on solid surface via laser processing  

SciTech Connect

In a safety operation of a nuclear power plant, vapor conditions such as a droplet or liquid membrane toward a solid surface of a heat exchanger and reactor vessel is important. In the present study, focusing on the droplet, the wettability on solid surface and surface free energy of solid are evaluated. In addition, wettability on a metal plate fabricated by laser processing is also considered for the nuclear engineering application.

Yonemoto, Yukihiro; Nishimura, Akihiko [Applied Laser Technology Institute, Japan Atomic Energy Agency, 65-20 Kizaki, Tsuruga, Fukui (Japan)

2012-07-11

370

Control of physical properties on solid surface via laser processing  

NASA Astrophysics Data System (ADS)

In a safety operation of a nuclear power plant, vapor conditions such as a droplet or liquid membrane toward a solid surface of a heat exchanger and reactor vessel is important. In the present study, focusing on the droplet, the wettability on solid surface and surface free energy of solid are evaluated. In addition, wettability on a metal plate fabricated by laser processing is also considered for the nuclear engineering application.

Yonemoto, Yukihiro; Nishimura, Akihiko

2012-07-01

371

Plymouth State Weather Center  

NSDL National Science Digital Library

The Plymouth State Weather Center provides a variety of weather information, including a tropical weather menu with current and archived data on tropical depressions, storms, or hurricanes in the Atlantic or Eastern Pacific Oceans. An interactive Weather Product Generator allows students to make their own surface data maps and meteograms (24-hour summaries of weather at a specific location), and view satellite imagery. There are also interactive weather maps for the U.S., Canada, and Alaska that display the latest observations, and text servers which provide current written observations for New England and North America. A set of past and current weather data products provides information on minimum and maximum temperatures, wind chill, and heat index. In addition, there are collections of satellite loops/movies, radar/lightning images, loops, and movies, and a set of tutorials on clouds, the sun and its effects on the environment, and balanced atmospheric flows.

372

Beyond the Weather Chart: Weathering New Experiences.  

ERIC Educational Resources Information Center

Describes an early childhood educator's approach to teaching children about rain, rainbows, clouds, precipitation, the sun, air, and wind. Recommends ways to organize study topics and describes experiments that can help children better understand the different elements of weather. (MOK)

Huffman, Amy Bruno

1996-01-01

373

Physical and chemical controls on the critical zone  

USGS Publications Warehouse

Geochemists have long recognized a correlation between rates of physical denudation and chemical weathering. What underlies this correlation? The Critical Zone can be considered as a feed-through reactor. Downward advance of the weathering front brings unweathered rock into the reactor. Fluids are supplied through precipitation. The reactor is stirred at the top by biological and physical processes. The balance between advance of the weathering front by mechanical and chemical processes and mass loss by denudation fixes the thickness of the Critical Zone reactor. The internal structure of this reactor is controlled by physical processes that create surface area, determine flow paths, and set the residence time of material in the Critical Zone. All of these impact chemical weathering flux.

Anderson, S.P.; Von Blanckenburg, F.; White, A.F.

2007-01-01

374

Physical processes affecting the sedimentary environments of Long Island Sound  

USGS Publications Warehouse

A modeling study was undertaken to simulate the bottom tidal-, wave-, and wind-driven currents in Long Island Sound in order to provide a general physical oceanographic framework for understanding the characteristics and distribution of seafloor sedimentary environments. Tidal currents are important in the funnel-shaped eastern part of the Sound, where a strong gradient of tidal-current speed was found. This current gradient parallels the general westward progression of sedimentary environments from erosion or non-deposition, through bedload transport and sediment sorting, to fine-grained deposition. Wave-driven currents, meanwhile, appear to be important along the shallow margins of the basin, explaining the occurrence of relatively coarse sediments in regions where tidal currents alone are not strong enough to move sediment. Finally, westerly wind events are shown to locally enhance bottom currents along the axial depression of the sound, providing a possible explanation for the relatively coarse sediments found in the depression despite tide- and wave-induced currents below the threshold of sediment movement. The strong correlation between the near-bottom current intensity based on the model results and the sediment response as indicated by the distribution of sedimentary environments provides a framework for predicting the long-term effects of anthropogenic activities.

Signell, R.P.; Knebel, H.J.; List, J.H.; Farris, A.S.

1997-01-01

375

Modelling of Complex Physical Processes in Electrostatic Precipitators  

NASA Astrophysics Data System (ADS)

Electrostatic precipitator (ESP) models have improved significantly in the past years. The dramatic development of the capacity of computers made it possible to increase the complexity of ESP models. Recently the different interactions between the gas, the electric field with ion space charge and the charged particles to be precipitated can be described more accurately by the newly developed complex approach. However even some of the newest computer models are limited; they are not able to follow the interactions of the complicated physical phenomena properly. For example pulse energisation of short time impulses cannot be described correctly with models assuming continuous corona current. There is another important problem, namely the examined duration of operation. Some of the models determine the trajectories of dust particles assuming that they are unchanged during the operation of an ESP. The validity of this assumption is very limited in such cases, where the development of certain phenomena is time dependent (e.g. back corona formation). In this paper the authors focus on the "long term" models, analysing such situations in which it is vital to investigate a longer period of operation of ESP-s. Using the newly developed model the effect of back corona, rapping, etc. can be analysed with higher reliability than it has been performed in previous ESP models.

Kiss, István; Iváncsy, Tamás; Suda, Jenõ; Berta, István

2011-06-01

376

Relationship between physical, chemical and processing properties of rice  

E-print Network

were -0. 973 for the batch process and -0, 971 for the individual sample techn1que. Biuret absorbance values were highly correlated with protein content as measured by the Kjeldahl method. To compare the accuracy of dye-binding techniques, biuret.... ); and dry matter loss (Loss) (Table 2). Since water uptake and alkali spreading concern the absorption of aqueous solutions by the intact endosperm, these relat1onsh1ps may be a function of the surface area of the kernel in addition to other physicochem1...

Parial, Lucila Beatrice Calupitan

2012-06-07

377

Valid Physical Processes from Numerical Discontinuities in Computational Fluid Dynamics  

E-print Network

Due to the limited cell resolution in the representation of flow variables, a piecewise continuous initial reconstruction with discontinuous jump at a cell interface is usually used in modern computational fluid dynamics methods. Starting from the discontinuity, a Riemann problem in the Godunov method is solved for the flux evaluation across the cell interface in a finite volume scheme. With the increasing of Mach number in the CFD simulations, the adaptation of the Riemann solver seems introduce intrinsically a mechanism to develop instabilities in strong shock regions. Theoretically, the Riemann solution of the Euler equations are based on the equilibrium assumption, which may not be valid in the non-equilibrium shock layer. In order to clarify the flow physics from a discontinuity, the unsteady flow behavior of one-dimensional contact and shock wave is studied on a time scale of (0~10000) times of the particle collision time. In the study of the non-equilibrium flow behavior from a discontinuity, the collision-less Boltzmann equation is first used for the time scale within one particle collision time, then the direct simulation Monte Carlo (DSMC) method will be adapted to get the further evolution solution. The transition from the free particle transport to the dissipative Navier-Stokes (NS) solutions are obtained as an increasing of time. The exact Riemann solution becomes a limiting solution with infinite number of particle collisions. For the high Mach number flow simulations, the points in the shock transition region, even though the region is enlarged numerically to the mesh size, should be considered as the points inside a highly non-equilibrium shock layer.

Kun Xu; Quanhua Sun; Pubing Yu

2010-09-22

378

Physical Processes for Driving Ionospheric Outflows in Global Simulations  

NASA Technical Reports Server (NTRS)

We review and assess the importance of processes thought to drive ionospheric outflows, linking them as appropriate to the solar wind and interplanetary magnetic field, and to the spatial and temporal distribution of their magnetospheric internal responses. These begin with the diffuse effects of photoionization and thermal equilibrium of the ionospheric topside, enhancing Jeans' escape, with ambipolar diffusion and acceleration. Auroral outflows begin with dayside reconnexion and resultant field-aligned currents and driven convection. These produce plasmaspheric plumes, collisional heating and wave-particle interactions, centrifugal acceleration, and auroral acceleration by parallel electric fields, including enhanced ambipolar fields from electron heating by precipitating particles. Observations and simulations show that solar wind energy dissipation into the atmosphere is concentrated by the geomagnetic field into auroral regions with an amplification factor of 10-100, enhancing heavy species plasma and gas escape from gravity, and providing more current carrying capacity. Internal plasmas thus enable electromagnetic driving via coupling to the plasma, neutral gas and by extension, the entire body " We assess the Importance of each of these processes in terms of local escape flux production as well as global outflow, and suggest methods for their implementation within multispecies global simulation codes. We complete 'he survey with an assessment of outstanding obstacles to this objective.

Moore, Thomas Earle; Strangeway, Robert J.

2009-01-01

379

Processing of speech signals for physical and sensory disabilities.  

PubMed Central

Assistive technology involving voice communication is used primarily by people who are deaf, hard of hearing, or who have speech and/or language disabilities. It is also used to a lesser extent by people with visual or motor disabilities. A very wide range of devices has been developed for people with hearing loss. These devices can be categorized not only by the modality of stimulation [i.e., auditory, visual, tactile, or direct electrical stimulation of the auditory nerve (auditory-neural)] but also in terms of the degree of speech processing that is used. At least four such categories can be distinguished: assistive devices (a) that are not designed specifically for speech, (b) that take the average characteristics of speech into account, (c) that process articulatory or phonetic characteristics of speech, and (d) that embody some degree of automatic speech recognition. Assistive devices for people with speech and/or language disabilities typically involve some form of speech synthesis or symbol generation for severe forms of language disability. Speech synthesis is also used in text-to-speech systems for sightless persons. Other applications of assistive technology involving voice communication include voice control of wheelchairs and other devices for people with mobility disabilities. Images Fig. 4 PMID:7479816

Levitt, H

1995-01-01

380

Programmer's Guide for FFORM. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.  

ERIC Educational Resources Information Center

This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. FFORM is a portable format-free input subroutine package written in ANSI Fortran IV…

Anderson, Lougenia; Gales, Larry

381

Phrases of the Kinetic: Dynamic Physicality as a Dimension of the Design Process  

E-print Network

1 Phrases of the Kinetic: Dynamic Physicality as a Dimension of the Design Process Amanda Jane of the body as an inherent part of the human side of a human-computer interaction, assuming that bodily construction and dynamics physics education with children; Kinetic Sketchup, a system for motion construction

Ishii, Hiroshi

382

Physical modeling and analysis of rain and clouds by anisotropic scaling multiplicative processes  

Microsoft Academic Search

We argue that the basic properties of rain and cloud fields (particularly their scaling and intermittency) are best understood in terms of coupled (anisotropic and scaling) cascade processes. We show how such cascades provide a framework not only for theoretically and empirically investigating these fields, but also for constructing physically based stochastic models. This physical basis is provided by cascade

Daniel Schertzer; Shaun Lovejoy

1987-01-01

383

Physics as quantum information processing1 Giacomo Mauro D'Ariano  

E-print Network

Physics as quantum information processing1 Giacomo Mauro D'Ariano QUIT Group, Dipartimento di at the foundations of Physics has been then considered, with space-time, Relativity, quantization rules and Quantum IV, Sezione di Pavia Abstract. The experience from Quantum Information has lead us to look at Quantum

D'Ariano, Giacomo Mauro

384

Applications of the First Law to Ecological Systems. Physical Processes in Terrestrial and Aquatic Ecosystems, Thermodynamics.  

ERIC Educational Resources Information Center

These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This report describes concepts presented in another module called "The First Law of…

Stevenson, R. D.

385

The First Law of Thermodynamics for Ecosystems. Physical Processes in Terrestrial and Aquatic Ecosystems, Thermodynamics.  

ERIC Educational Resources Information Center

These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module and a comparison module are concerned with elementary concepts of thermodynamics as…

Stevenson, R. D.

386

THE PHYSICS OF ARC WELDING PROCESSES Department of Materials Science and Engineering,  

E-print Network

) THE PHYSICS OF ARC WELDING PROCESSES T.W.EAGAR Department of Materials Science and Engineering Wor ds: Arc Welding, Arc Physics, Shielding Gases, Gas Metal Arc Welding. 1. Introduction Langmuir for t hese people to study. Stated simply, atmospheric pressure arcs and welding present problems vlhich

Eagar, Thomas W.

387

Mechanical, thermal and physical coupling methods in FE analysis of metal forming processes  

Microsoft Academic Search

The thermal and mechanical equations for large deformations occuring in metal forming processes are recalled. The finite element approaches for viscoplastic or for elastic viscoplastic materials are presented briefly. The coupling of the previous equations with those describing the evolution of physical internal parameters is analysed. A compact form of the physical and mechanical equation is used to consider any

J.-L. Chenot; Y. Chastel

1996-01-01

388

P33455 MODELING CHEMICAL AND PHYSICAL PROCESSES IN LEACHING SOLIDIFIED WASTES zq#n?2k=  

E-print Network

Solidification is an important treatment process in hazardous waste management and will continue to be so until waste minimization and waste recycle processes are perfected for all hazardous wastes. It is generally recognized that immobilization of contaminants in solidified wastes occurs through both physical and chemical mechanisms. Standard techniques for analyzing contaminant leaching measure only an observed diffusivity that does not separate chemical and physical factors. The suitability of the standard data analysis procedure is reviewed and alternative models developed that describe the separate effects of chemical and physical processes. These models describe physical transport through a solidified waste matrix according to Fick's law. Chemical reactions of sorption/desorption and precipitation/ dissolution are described. The observed diffusivity that would be calculated by ignoring chemical processes is shown to depend on the true effective diffusivity and coefficients that describe the chemical phenomena.

Bill Batchelor

389

PHYSICAL REVIEW E 86, 011137 (2012) Demographic noise and piecewise deterministic Markov processes  

E-print Network

PHYSICAL REVIEW E 86, 011137 (2012) Demographic noise and piecewise deterministic Markov processes of the stochastic transitions of the discrete variables. Here, we are also interested in the nonequilibrium

McKane, Alan

390

Physical Processes Influencing Atmospheric Trace Constituents Measured from Aircraft in Trace-P  

NASA Technical Reports Server (NTRS)

This paper presents a final report on physical processes influencing atmospheric trace constituents measured for aircraft in trace-P. This report covers the period of July 21, 2000 through October 31, 2003.

Newell, Reginald E.; Plumb, R. Alan

2003-01-01

391

Development of a Fast and Detailed Model of Urban-Scale Chemical and Physical Processing  

E-print Network

A reduced form metamodel has been produced to simulate the effects of physical, chemical, and meteorological processing of highly reactive trace species in hypothetical urban areas, which is capable of efficiently simulating ...

Prinn, Ronald G.

392

Reviews Book: Marie Curie and Her Daughters Resource: Cumulus Equipment: Alpha Particle Scattering Apparatus Equipment: 3D Magnetic Tube Equipment: National Grid Transmission Model Book: Einstein's Physics Equipment: Barton's Pendulums Equipment: Weather Station Web Watch  

NASA Astrophysics Data System (ADS)

WE RECOMMEND Marie Curie and Her Daughters An insightful study of a resilient and ingenious family and their achievements Cumulus Simple to install and operate and with obvious teaching applications, this weather station 'donationware' is as easy to recommend as it is to use Alpha Particle Scattering Apparatus Good design and construction make for good results National Grid Transmission Model Despite its expense, this resource offers excellent value Einstein's Physics A vivid, accurate, compelling and rigorous treatment, but requiring an investment of time and thought WORTH A LOOK 3D Magnetic Tube Magnetic fields in three dimensions at a low cost Barton's Pendulums A neat, well-made and handy variant, but not a replacement for the more traditional version Weather Station Though not as robust or substantial as hoped for, this can be put to good use with the right software WEB WATCH An online experiment and worksheet are useful for teaching motor efficiency, a glance at CERN, and NASA's interesting information on the alpha-magnetic spectrometer and climate change

2013-09-01

393

Space Weathering in the Mercurian Environment  

NASA Technical Reports Server (NTRS)

Space weathering processes are known to be important on the Moon. These processes both create the lunar regolith and alter its optical properties. Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will also incur the effects of space weathering. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes and the products of those processes. It should be possible to observe the effects of these differences in Vis (visible)/NIR (near infrared) spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the Fe content of the Mercurian surface. Additional information is contained in the original extended abstract.

Noble, S. K.; Pieters, C. M.

2001-01-01

394

Weather and Atmosphere  

NSDL National Science Digital Library

In this unit, students learn the basics about weather and the atmosphere. They investigate materials engineering as it applies to weather and the choices available to us for clothing to counteract the effects of weather. Students have the opportunity to design and analyze combinations of materials for use in specific weather conditions. In the next lesson, students also are introduced to air masses and weather forecasting instrumentation and how engineers work to improve these instruments for atmospheric measurements on Earth and in space. Then, students learn the distinguishing features of the four main types of weather fronts that accompany high and low pressure air masses and how those fronts are depicted on a weather map. During this specific lesson, students learn different ways that engineers help with storm prediction, analysis and protection. In the final lesson, students consider how weather forecasting plays an important part in their daily lives by learning about the history of weather forecasting and how improvements in weather technology have saved lives by providing advance warning of natural disasters.

Integrated Teaching And Learning Program

395

Analysis of physical-chemical processes governing SSME internal fluid flows  

NASA Technical Reports Server (NTRS)

The basic issues concerning the physical chemical processes of the Space Shuttle Main Engine are discussed. The objectives being to supply the general purpose CFD code PHOENICS and the associated interactive graphics package - GRAFFIC; to demonstrate code usage on SSME related problems; to perform computations and analyses of problems relevant to current and future SSME's; and to participate in the development of new physical models of various processes present in SSME components. These objectives are discussed in detail.

Singhal, A. K.; Owens, S. F.; Mukerjee, T.; Prakash, C.; Przekwas, A. J.; Kannapel, M.

1985-01-01

396

Integrating Physical and Chemical Alteration Mechanisms of Soil Formation on Mars from the Mars Exploration Rovers  

Microsoft Academic Search

Models of soil formation by chemical weathering must also incorporate physical processes including impact gardening and aeolian transport to remove and concentrate olivine and explain the compositional scatter of soils along the olivine-feldspar join.

I. O. McGlynn; H. Y. McSween; C. M. Fedo

2011-01-01

397

The weathering of the PVC insulation of overhead lines 2. Comparison of natural and artificial weathering  

SciTech Connect

The factors which influence the weathering in the UK of green poly(vinyl chloride) - PVC - used as insulation for overhead power lines have been investigated. Degradation processes such as surface cracking, bulk cracking and color change are explaind with reference to PVC composition. It is shown that artificial, accelerated weathering in a Xenotest-150 machine correlates well with long-term natural weathering, and can be successfully used for the rapid assessment of new compounds.

Le Poidevin, G.J.

1981-10-01

398

Student Understanding of the Physics and Mathematics of Process Variables in P-V Diagrams  

NSDL National Science Digital Library

Students in an upper-level thermal physics course were asked to compare quantities related to the First Law of Thermodynamics along with similar mathematical questions devoid of all physical context. We report on a comparison of student responses to physics questions involving interpretation of ideal gas processes on P-V diagrams and to analogous mathematical qualitative questions about the signs of and comparisons between the magnitudes of various integrals. Student performance on individual questions combined with performance on the paired questions shows evidence of isolated understanding of physics and mathematics. Some difficulties are addressed by instruction.

Pollock, Evan B.; Thompson, John R.; Mountcastle, Donald B.

2009-06-24

399

Searching for deep understanding : implementing a mechanical engineering design process in K9-K12 physics classrooms to identify and improve levels of physics intuition and content  

E-print Network

This experiment tested the level of Physics content knowledge of various K9-K12 Physics students in a local Boston high school by having them implement a mechanical engineering design process to solve open-ended design ...

Williams, John Alejandro

2010-01-01

400

Introduction of a pyramid guiding process for general musculoskeletal physical rehabilitation  

PubMed Central

Successful instruction of a complicated subject as Physical Rehabilitation demands organization. To understand principles and processes of such a field demands a hierarchy of steps to achieve the intended outcome. This paper is intended to be an introduction to a proposed pyramid scheme of general physical rehabilitation principles. The purpose of the pyramid scheme is to allow for a greater understanding for the student and patient. As the respected Food Guide Pyramid accomplishes, the student will further appreciate and apply supported physical rehabilitation principles and the patient will understand that there is a progressive method to their functional healing process. PMID:16759396

Stark, Timothy W

2006-01-01

401

NOAA Daily Weather Maps  

NSDL National Science Digital Library

The charts on this website are the principal charts of the former Weather Bureau publication, "Daily Weather Map." They are the Surface Weather Map, the 500-Millibar Height Contours chart, the Highest and Lowest Temperatures chart, and the Precipitation Areas and Amounts chart. For each day, simple charts are arranged on a single page. These charts are the surface analysis of pressure and fronts, color shading, in ten degree intervals,of maximum and minimum temperature, 500-Millibar height contours, and color shaded 24-hour total precipitation. These charts act as links to their respective Daily Weather Map charts. All charts are derived from the operational weather maps prepared at the National Centers for Environmental Prediction, Hydrometeorological Prediction Center, National Weather Service.

Center, Hydrometeorological P.

2011-01-01

402

Weather and Climate Data  

NSDL National Science Digital Library

The Weather and Climate Data site for the Center for Ocean-Land-Atmosphere Studies (COLA) contains analyses of current conditions and the state of the atmosphere; weather forecasts; metropolitan quick-look weather summaries and meteograms; short-term climate outlooks for temperature, precipitation and soil moisture; El Nino forecasts for understanding the ocean-atmosphere system; and maximum potential hurricane intensity maps showing potential minimum pressure and potential maximum winds for the oceans.

403

Space Weather Media Viewer  

NSDL National Science Digital Library

This is version 3 of the space Weather Media Viewer, created to work with the space Weather Action Center to see near-real time data and to provide additional images and resources available for educational use. It features easy downloads that can also be added to news reports and space weather reports. It was designed for ease in adding any media (videos, images) data.

2011-01-01

404

Winter weather activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Weather Maker Simulator Use the weather simulation above to answer the following questions in complete sentences on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there is high ...

Frankovic, Whitney

2009-09-28

405

Weather Radar Fundamentals  

NSDL National Science Digital Library

This 2-hour module presents the fundamental principles of Doppler weather radar operation and how to interpret common weather phenomena using radar imagery. This is accomplished via conceptual animations and many interactive radar examples in which the user can practice interpreting both radar reflectivity and radar velocity imagery. Although intended as an accelerated introduction to understanding and using basic Doppler weather radar products, the module can also serve as an excellent refresher for more experienced users.

Comet

2012-03-21

406

Weather and climate  

NASA Technical Reports Server (NTRS)

Recommendations for using space observations of weather and climate to aid in solving earth based problems are given. Special attention was given to: (1) extending useful forecasting capability of space systems, (2) reducing social, economic, and human losses caused by weather, (3) development of space system capability to manage and control air pollutant concentrations, and (4) establish mechanisms for the national examination of deliberate and inadvertent means for modifying weather and climate.

1975-01-01

407

Ch.13 Weathering, Karst Landscapes, and Mass Movement  

E-print Network

Ch.13 Weathering, Karst Landscapes, and Mass Movement #12;Learning Objective One: ! Landmass that wears away or rearranges landforms. ! The principle denudation processes are weathering, mass movement at different rates. #12;Differential weathering Delicate Arch, Arches National Park, Utah #12;Landscape System

Pan, Feifei

408

Studies of Fe/sup 2 +/. -->. Fe/sup 3 +/ transitions during the process of rock weathering by nuclear gamma-resonance spectroscopy  

SciTech Connect

This paper presents a method for the mineral and weathering assessment of rocks and carbonaceous matter based in gamma spectroscopy and transitions between iron ions. The method is applied to rocks collected near the Teberda preserve. Four latitudinal bands of rocks parallel to the Greater Caucasus Ridge are identified in this territory. Isomer shift and hyperfine parameters of the Moessbauer spectra are given.

Vasil'ev, S.P.; Babanin, V.F.; Solov'ev, A.A.

1986-11-01

409

Results from the Second Forum on the Future Role of the Human in the Forecast Process. Part II: Cognitive Psychological Aspects of Expert Weather Forecasters  

E-print Network

, Wakefield, Virginia DAVID M. SCHULTZ Cooperative Institute for Mesoscale Meteorological Studies, University on the cognitive psychological aspects of expert weather forecasters. The first presentation discussed the learning, and are described in sections 2, 3 and 4. a. Dr. David M. Schultz (Cooperative Institute for Mesoscale

Schultz, David

410

Pilot Weather Advisor System  

NASA Technical Reports Server (NTRS)

The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understand

Lindamood, Glenn; Martzaklis, Konstantinos Gus; Hoffler, Keith; Hill, Damon; Mehrotra, Sudhir C.; White, E. Richard; Fisher, Bruce D.; Crabill, Norman L.; Tucholski, Allen D.

2006-01-01

411

Weather assessment and forecasting  

NASA Technical Reports Server (NTRS)

Data management program activities centered around the analyses of selected far-term Office of Applications (OA) objectives, with the intent of determining if significant data-related problems would be encountered and if so what alternative solutions would be possible. Three far-term (1985 and beyond) OA objectives selected for analyses as having potential significant data problems were large-scale weather forecasting, local weather and severe storms forecasting, and global marine weather forecasting. An overview of general weather forecasting activities and their implications upon the ground based data system is provided. Selected topics were specifically oriented to the use of satellites.

1977-01-01

412

Winter Storm (weather)  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. First think about these questions: 1. What is your favorite aspect of winter weather? 2. How does the weather effect your everyday life? Form groups of THREE. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper... 1. In general, when are winds formed? 2. When winds are blowing, how can you ...

Miller, Aubree

2009-09-28

413

Washington Post Weather  

NSDL National Science Digital Library

The Washington Post makes a bid for the already crowded Internet weather market with WeatherPost. Coverage includes current conditions and four-day forecasts for 3,600 cities worldwide, as well as snapshot and time-lapse satellite maps (provided by Accu Weather). For US cities, users may also access UV and air quality maps and data, as well as seasonal maps (snow cover, tanning index, heat index, and BeachCast) and other radar images such as precipitation. Users may enter a city name into the homepage search box, or may browse by country or state/province. The historical weather database offers compiled monthly average weather data for nearly 1,000 cities worldwide; the database is searchable. An aspect of the site that sets it apart from many other weather pages is the weather reference desk, which includes a weather glossary, weather calculators (JavaScript converters for temperature, wind chill, heat index, etc.) and a page devoted to storm chasers.

1997-01-01

414

Space Weather: Welcome, SEC  

NSDL National Science Digital Library

This video presentation welcomes the Space Weather Prediction Center, formerly known as the Space Environment Center or SEC to the National Weather Service (NWS) as an operational entity of the National Centers for Environmental Prediction (NCEP) family. Describing the ways in which space weather affects global communications and power resources, it demonstrates the importance of space weather forecasting as a part of the NWS family of services. With the inclusion of SWPC, the NWS now provides environmental understanding from the sun to the sea.

Comet

2005-01-11

415

Meteorology:Meteorology: Weather and ClimateWeather and Climate  

E-print Network

1 Meteorology:Meteorology: Weather and ClimateWeather and Climate Large Scale Weather SystemsLarge--scale Weather Systemsscale Weather Systems Tropical cyclones (1-2) Location, Structure, Life-cycle Formation and modification, airmasses that effect the British Isles Airmasses affecting the British Isles

416

Efficient Physical Embedding of Topologically Complex Information Processing Networks in Brains and Computer Circuits  

Microsoft Academic Search

Nervous systems are information processing networks that evolved by natural selection, whereas very large scale integrated (VLSI) computer circuits have evolved by commercially driven technology development. Here we follow historic intuition that all physical information processing systems will share key organizational properties, such as modularity, that generally confer adaptivity of function. It has long been observed that modular VLSI circuits

Danielle S. Bassett; Daniel L. Greenfield; Andreas Meyer-Lindenberg; Daniel R. Weinberger; Simon W. Moore; Edward T. Bullmore

2010-01-01

417

Feel Good--Be Good: Subject Content and Governing Processes in Physical Education  

ERIC Educational Resources Information Center

Background: In this paper a study of both subject "content" and governing "processes" in Swedish physical education is presented. The reason why an analysis of both content and processes is of special interest is that it makes it possible to understand the encounter between the institutional level and the practice of education. Purpose: The…

Ohman, Marie; Quennerstedt, Mikael

2008-01-01

418

Overland erosion of uranium-mill-tailings impoundments: physical processes and computational methods  

SciTech Connect

The surface runoff and erosional processes of watersheds caused by rainfall-runoff are reviewed. Soil properties, topography, and rainstorm distribution are discussed with respect to their effects on soil erosion. The effects of climate and vegetation are briefly presented. Regression models and physical process simulation models are reviewed.

Walters, M.H.

1983-03-01

419

Weather and emotional state  

NASA Astrophysics Data System (ADS)

Introduction Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychic and emotional level has been made. Emotions affect the bio-tonus, working ability and concentration, hence their significance in various domains of economic life, such as health care, education, transportation, tourism, etc. Data and methods The research has been made in Sofia City within a period of 8 months, using 5 psychological methods (Eysenck Personality Questionnaire (EPQ), State-Trait Anxiety Inventory (STAI), Test for Self-assessment of the emotional state (developed by Wessman and Ricks), Test for evaluation of moods and Test "Self-confidence - Activity - Mood" (developed by the specialists from the Military Academy in Saint Petersburg). The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions because of the purpose to include in the analysis a maximal number of meteorological elements. 16 weather types are defined in dependence of the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were considered as well. Results and discussions The results obtained by t-test show that the different categories of weather lead to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effect on human emotions but only when a transition to the cloudy weather or weather type, classified as "unfavourable" has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension "neuroticism", has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more "protected" to the weather influence on their emotions, while those who are emotionally unstable have a stronger dependence to the impacts of the weather.

Spasova, Z.

2010-09-01

420

Weathering: methods and techniques to measure  

NASA Astrophysics Data System (ADS)

Surface recession takes place when weathered material is removed from the rocks. In order to know how fast does weathering and erosion occur, a review of several methods, analyses and destructive and non-destructive techniques to measure weathering of rocks caused by physico-chemical changes that occur in bedrocks due to salt crystallization, freezing-thaw, thermal shock, influence of water, wind, temperature or any type of environmental agent leading to weathering processes and development of soils, in-situ in the field or through experimental works in the laboratory are addressed. From micro-scale to macro-scale, from the surface down to more in depth, several case studies on in-situ monitoring of quantification of decay on soils and rocks from natural landscapes (mountains, cliffs, caves, etc) or from urban environment (foundations or facades of buildings, retaining walls, etc) or laboratory experimental works, such as artificial accelerated ageing tests (a.a.e.e.) or durability tests -in which one or more than one weathering agents are selected to assess the material behaviour in time and in a cyclic way- performed on specimens of these materials are summarised. Discoloration, structural alteration, precipitation of weathering products (mass transfer), and surface recession (mass loss) are all products of weathering processes. Destructive (SEM-EDX, optical microscopy, mercury intrusion porosimetry, drilling resistance measurement, flexural and compression strength) and Non-destructive (spectrophotocolorimetry, 3D optical surface roughness, Schmidt hammer rebound tester, ultrasound velocity propagation, Nuclear Magnetic Resonance NMR, X ray computed micro-tomography or CT-scan, geo-radar differential global positioning systems) techniques and characterization analyses (e.g. water absorption, permeability, open porosity or porosity accessible to water) to assess their morphological, physico-chemical, mechanical and hydric weathering; consolidation products or methods to stop or to slow down their weathering or durability and stability of soils and rocks are also topics where the methods and techniques deal with the quantification of weathering. Cultural stone weathering studies contribute substantially to the knowledge of weathering rates revealing the importance of specific weathering agents and weathering factors.

Lopez-Arce, P.; Zornoza-Indart, A.; Alvarez de Buergo, M.; Fort, R.

2012-04-01

421

The weathering of the PVC insulation of overhead lines 2. Comparison of natural and artificial weathering  

Microsoft Academic Search

The factors which influence the weathering in the UK of green poly(vinyl chloride) - PVC - used as insulation for overhead power lines have been investigated. Degradation processes such as surface cracking, bulk cracking and color change are explaind with reference to PVC composition. It is shown that artificial, accelerated weathering in a Xenotest-150 machine correlates well with long-term natural

Le Poidevin

1981-01-01

422

Weather: You Like It or Not - Learning about the Importance of and Flaws in Weather Prediction  

NSDL National Science Digital Library

In this lesson, students explore the importance of weather prediction and learn about some of the flaws inherent in the process. By researching specific storm types, they are able to prepare and deliver their own weather reports. The material includes links to additional information and resources.

Klein, Rachel M.

2001-03-07

423

Designing a Weather Station  

ERIC Educational Resources Information Center

The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

Roman, Harry T.

2012-01-01

424

Mild and Wild Weather.  

ERIC Educational Resources Information Center

Presents background information and six activities that focus on clouds, precipitation, and stormy weather. Each activity includes an objective, recommended age level(s), subject area(s), and instructional strategies. Also provided are two ready-to-copy pages (a coloring page on lightning and a list of weather riddles to solve). (JN)

NatureScope, 1985

1985-01-01

425

People and Weather.  

ERIC Educational Resources Information Center

Provides: (1) background information on ways weather influences human lives; (2) activities related to this topic; and (3) a ready-to-copy page with weather trivia. Each activity includes an objective, list of materials needed, recommended age level(s), subject area(s), and instructional strategies. (JN)

NatureScope, 1985

1985-01-01

426

Weather Cardboard Carpentry  

ERIC Educational Resources Information Center

Included are instructions and diagrams for building weather instruments (wind vane, Celsius temperature scale, and anemometer) from simple tools and Tri-Wall, a triple-thick corrugated cardboard. Ordering sources for Tri-Wall are listed. Additional weather instruments that can be constructed are suggested. (CS)

DeBruin, Jerome E.

1977-01-01

427

Weathering warming in Colorado  

SciTech Connect

This article describes the results of a field experiment heating patches of a subalpine meadow in the Rocky Mountains to determine what will weather and what will weather under projected global warming. The problems with actually measuring the feedback is discussed, along with the changes which come as the meadow is heated.

Gillis, A.M.

1996-03-01

428

Teacher's Weather Sourcebook.  

ERIC Educational Resources Information Center

This book is a teaching resource for the study of weather-related phenomena. A "weather unit" is often incorporated into school study because of its importance to our daily lives and because of its potential to cut across disciplinary content. This book consists of two parts. Part I covers the major topics of atmospheric science such as the modern…

Konvicka, Tom

429

Critical Fire Weather Patterns  

E-print Network

-- 1.1 Typical Summer Weather Cycle PDT -- 1.1 Dry Thunderstorms PHX -- 1.1 North Winds PHX -- 2 Thunderstorms RNO -- 1.1 Washoe Zephyr RNO -- 2.1 Winds & Thunderstorms SAC -- 1.1 Pre--Frontal Winds SLC -- 1 days. Normally the pacific weather front will have enough instability for a few dry thunderstorms

Clements, Craig

430

What Is Space Weather?  

NSDL National Science Digital Library

This resource provides a brief overview of the phenomenon known as space weather, which happens when energetic particles emitted by the Sun impact the Earth's magnetosphere. Users can view images, video clips, and animations of auroras and other types of space weather. A set of links to related websites is also provided.

431

Benign Weather Modification.  

National Technical Information Service (NTIS)

Weather modification is a technology once embraced by the U.S. military as a tool to help both wartime and peacetime missions. However, interest in the ability to modify weather has waned over recent years and is now nearly non-existent. This study examin...

B. E. Coble

1996-01-01

432

Benign Weather Modification.  

National Technical Information Service (NTIS)

Weather modification is a technology once embraced by the United States (US) military as a tool to help both wartime and peacetime missions. However, interest in the ability to modify weather has waned over recent years and is now nearly nonexistent. This...

B. B. Coble

1997-01-01

433

Weathering Database Technology  

ERIC Educational Resources Information Center

Collecting weather data is a traditional part of a meteorology unit at the middle level. However, making connections between the data and weather conditions can be a challenge. One way to make these connections clearer is to enter the data into a database. This allows students to quickly compare different fields of data and recognize which…

Snyder, Robert

2005-01-01

434

Exercising in Cold Weather  

MedlinePLUS

... www.nia.nih.gov/Go4Life Exercising in Cold Weather Exercise has benefits all year, even during winter. ... activities when it’s cold outside: l Check the weather forecast. If it’s very windy or cold, exercise ...

435

Fabulous Weather Day  

ERIC Educational Resources Information Center

Each year, first graders at Kensington Parkwood Elementary School in Kensington, Maryland, look forward to Fabulous Weather Day. Students learn how meteorologists collect data about the weather, how they study wind, temperature, precipitation, basic types/characteristics of clouds, and how they forecast. The project helps the students grow in…

Marshall, Candice; Mogil, H. Michael

2007-01-01

436

On Observing the Weather  

ERIC Educational Resources Information Center

Rain, sun, snow, sleet, wind... the weather affects everyone in some way every day, and observing weather is a terrific activity to attune children to the natural world. It is also a great way for children to practice skills in gathering and recording information and to learn how to use simple tools in a standardized fashion. What better way to…

Crane, Peter

2004-01-01

437

Growing Up Fast: Stress Exposure and Subjective "Weathering" in Emerging Adulthood  

ERIC Educational Resources Information Center

We examine "subjective weathering" among females entering adulthood, using three waves of a national study. Subjective weathering is a social psychological component of aging that is associated with "physical weathering" previously observed in research on physical health. We examine the influence of stressors from childhood and adolescence on…

Foster, Holly; Hagan, John; Brooks-Gunn, Jeanne

2008-01-01

438

Scholastic: Weather Watch  

NSDL National Science Digital Library

The Weather Watch series of online projects investigates seasonal weather phenomena. Students discover the scientific explanations for these events, and use tools and resources for enhanced research. The Hurricanes project allows students to monitor patterns and plot the progression of hurricanes. The Winter Storms project contains an interactive weather maker allowing students to create different weather patterns by changing factors. A winter storm timeline provides stories of the harshest blizzards that have occurred in the U.S. The Weather Reporters project includes a selection of hands-on science experiments for classroom participation, leading up to sharing results online with students worldwide. Each project provides assessment tools and lesson plan suggestions for educators. Links are provided for additional resources.

439

System Science approach to Space Weather forecast  

NASA Astrophysics Data System (ADS)

There are many dynamical systems in nature that are so complex that mathematical models of their behaviour can not be deduced from first principles with the present level of our knowledge. Obvious examples are organic cell, human brain, etc often attract system scientists. A example that is closer to space physics is the terrestrial magnetosphere. The system approach has been developed to understand such complex objects from the observation of their dynamics. The systems approach employs advanced data analysis methodologies to identify patterns in the overall system behaviour and provides information regarding the linear and nonlinear processes involved in the dynamics of the system. This, in combination with the knowledge deduced from the first principles, creates the opportunity to find mathematical relationships that govern the evolution of a particular physical system. Advances and problems of systems science applications to provide a reliable forecasts of space weather phenomena such as geomagnetic storms, substorms and radiation belts particle fluxes are reviewed and compared with the physics based models.

Balikhin, Michael A.

440

Predicting the Weather  

NSDL National Science Digital Library

This Topic in Depth explores the science behind predicting the weather. First, the United States Search and Rescue Task Force describe the basic tools and knowledge used to create weather forecasts (1). Students can find concise, clear explanations of weather, fronts and air masses, high and low pressure, precipitation, and water vapor and humidity as well. By performing the activities presented in the second website, fourth grade students can learn about weather instruments and data collection (2). This website, produced by the Government of Saskatchewan, also explores how the weather can impact local communities. Third, Edheads offers a Macromedia Flash Player enhanced interactive module allowing students to predict the weather by examining weather maps (3 ). Through this website, users can become familiar with the concepts of warm and cold fronts, wind direction and speed, air pressure, and humidity. The fourth website, supplied by Annenberg / CPB, discusses weather satellites, Doppler radar, and additional tools forecasters use to predict the weather (4). Students can find a wind chill calculator along with a brief discussion of the history of forecasting and weather lore. Next, NOAA provides graphics for five forecast models: the ETA, the Global Forecast System (GFS), the Wave Watch III (WW3), the Nested Grid model (NGM), and the Rapid Update Cycle (RUC) (5). Outputs are available for North America, North Pacific, Western North Atlantic, and the Polar Ice Drift. Users can find links to detailed descriptions of the inputs and history of each model. Sixth, the British government's Met Office describes numerical modeling and its components (6). Students and educators can learn about the future in forecasting as well as educational opportunities with the Cooperative Program for Meteorology, Education, and Training (COMET).

441

Electron-ion collisions. [Basic physics of inelastic processes of excitation, ionization, and recombination  

SciTech Connect

This discussion concentrates on basic physics aspects of inelastic processes of excitation, ionization, and recombination that occur during electron-ion collisions. Except for cases of illustration along isoelectronic sequences, only multicharged (at least +2) ions will be specifically discussed with some emphasis of unique physics aspects associated with ionic charge. The material presented will be discussed from a primarily experimental viewpoint with most attention to electron-ion interacting beams experiments.

Crandall, D.H.

1982-01-01

442

Sediment and process water characterization in support of 300 Area North Process Pond physical soil washing test  

SciTech Connect

The sediments in the 300 Area North Process Pond are being considered for clean-up using soil washing processes. Prior to site clean-up several preliminary pilot-scale physical washing campaigns were performed by Westinghouse Hanford Company (WHC) staff in the summer of 1993. WHC used equipment that was obtained from the US Environmental Protection Agency. Specific details are found in the 300-FF-1 Physical Separations CERCLA Treatability Test Plan. Physical soil washing includes separation and proper containment of the contaminant-rich fines and residual liquid effluent and release of the coarse ``clean`` fraction, should it meet minimum performance levels for residual contaminant concentration to the site being cleaned. A goal of the demonstration is to concentrate the contaminants into {le}10% of the soil volume excavated and, therefore, to release {ge}90% of the soil back to the site as clean soil. To support interpretation of the WHC soil washing treatability study, PNL performed some sediment and process water characterization on samples taken during three major and one small campaign. This report documents particle-size distributions in various field washed piles, and chemical and gama emitting radionuclide contents as a function of particle-size distribution for the field washed sediments and contents in the spent process water. All of the particle fractions were separated by wet sieving, but two field samples were also subjected to dry sieving and attrition scrubbing followed by wet sieving.

Field, J.G.

1994-02-18

443

Space Weather, Environment and Societies  

NASA Astrophysics Data System (ADS)

Our planet exists within a space environment affected by constantly changing solar atmosphere producing cosmic particles and electromagnetic waves. This "space weather" profoundly influences the performance of our technology because we primarily use two means for transmitting information and energy; namely, electromagnetic waves and electricity. On an everyday basis, we have developed methods to cope with the normal conditions. However, the sun remains a fiery star whose 'angry' outbursts can potentially destroy spacecrafts, kill astronauts, melt electricity transformers, stop trains, and generally wreak havoc with human activities. Space Weather is the developing field within astronomy that aims at predicting the sun's violent activity and minimizing the impacts on our daily lives. Space Weather, Environment, and Societies explains why our technological societies are so dependent on solar activity and how the Sun disturbs the transmission of information and energy. Footnotes expand specific points and the appendices facilitate a more thorough command of the physics involved. Link: http://www.springer.com/sgw/cda/frontpage/0,11855,5-102-22-90815733-0,00.html?changeHeader=true

Lilensten, Jean; Bornarel, Jean

2005-12-01

444

Behavior of major and trace elements during weathering of sericite-quartz schist  

NASA Astrophysics Data System (ADS)

Two regolith profiles developed on the sericite-quartz schist in subtropical humid environment were selected to investigate behaviors of major and trace elements during weathering in Mengman gold deposit of Yunnan province, China. One profile located in the mining district sheared by a fault and the other was outside the mining area which represented the normal weathering profile on the schist. Regolith samples were collected in both profiles sequentially. Thirteen major oxides and 23 trace elements (including REE) were analyzed and their behaviors were compared in these two profiles. Based on the idea that immobile element is just a relative notion, we presented a method of immobile plateau to determine immobile elements during each stage in a progressive geochemical process and used mass ratio ( MR) to calculate the percentage of gain or loss ( X gp) of each element during the whole process. In both profiles, only TiO 2 was immobile during the whole weathering. The regolith profile formed on the mineralized schist recorded the weathering process more sensitively than the regolith profile on the normal schist. REE was mobile and fractionated during the schist weathering. LREE was loss in mass during the soil development stage which resulted from the chemical leaching, but was gain in mass during the pedogenesis stage because of the preferential absorption of soil to LREE. The LREE depletion near the fault during weathering was the collective effects of chemical leaching and physical accumulation. HFSE were all mobile in the mineralized regolith profile especially near the fault. But Nb-Ta and Zr-Hf were covariant in both profiles during the schist weathering.

Gong, Qingjie; Deng, Jun; Yang, Liqiang; Zhang, Jing; Wang, Qingfei; Zhang, Gaixia

2011-07-01