These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

An undergraduate laboratory experiment on quantized conductance in nanocontacts  

E-print Network

. Nanostructure fabrication has typically involved electron- beam lithography, either to directly create metalAn undergraduate laboratory experiment on quantized conductance in nanocontacts E. L. Foley, D laboratory experiment on conductance steps observed to occur near integer multiples of 2e2 /h as nanocontacts

La Rosa, Andres H.

2

Portable conduction velocity experiments using earthworms for the college and high school neuroscience teaching laboratory.  

PubMed

The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities that can be easily measured by manipulating electrode placement and the tactile stimulus. Here, we present a portable and robust experimental setup that allows students to perform conduction velocity measurements within a 30-min to 1-h laboratory session. Our improvement over this well-known preparation is the combination of behaviorally relevant tactile stimuli (avoiding electrical stimulation) with the invention of minimal, low-cost, and portable equipment. We tested these experiments during workshops in both a high school and college classroom environment and found positive learning outcomes when we compared pre- and posttests taken by the students. PMID:24585472

Shannon, Kyle M; Gage, Gregory J; Jankovic, Aleksandra; Wilson, W Jeffrey; Marzullo, Timothy C

2014-03-01

3

Biochar-Induced Changes in Soil Hydraulic Conductivity and Dissolved Nutrient Fluxes Constrained by Laboratory Experiments  

PubMed Central

The addition of charcoal (or biochar) to soil has significant carbon sequestration and agronomic potential, making it important to determine how this potentially large anthropogenic carbon influx will alter ecosystem functions. We used column experiments to quantify how hydrologic and nutrient-retention characteristics of three soil materials differed with biochar amendment. We compared three homogeneous soil materials (sand, organic-rich topsoil, and clay-rich Hapludert) to provide a basic understanding of biochar-soil-water interactions. On average, biochar amendment decreased saturated hydraulic conductivity (K) by 92% in sand and 67% in organic soil, but increased K by 328% in clay-rich soil. The change in K for sand was not predicted by the accompanying physical changes to the soil mixture; the sand-biochar mixture was less dense and more porous than sand without biochar. We propose two hydrologic pathways that are potential drivers for this behavior: one through the interstitial biochar-sand space and a second through pores within the biochar grains themselves. This second pathway adds to the porosity of the soil mixture; however, it likely does not add to the effective soil K due to its tortuosity and smaller pore size. Therefore, the addition of biochar can increase or decrease soil drainage, and suggests that any potential improvement of water delivery to plants is dependent on soil type, biochar amendment rate, and biochar properties. Changes in dissolved carbon (C) and nitrogen (N) fluxes also differed; with biochar increasing the C flux from organic-poor sand, decreasing it from organic-rich soils, and retaining small amounts of soil-derived N. The aromaticity of C lost from sand and clay increased, suggesting lost C was biochar-derived; though the loss accounts for only 0.05% of added biochar-C. Thus, the direction and magnitude of hydraulic, C, and N changes associated with biochar amendments are soil type (composition and particle size) dependent. PMID:25251677

Barnes, Rebecca T.; Gallagher, Morgan E.; Masiello, Caroline A.; Liu, Zuolin; Dugan, Brandon

2014-01-01

4

Portable Conduction Velocity Experiments Using Earthworms for the College and High School Neuroscience Teaching Laboratory  

ERIC Educational Resources Information Center

The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction

Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey; Marzullo, Timothy C.

2014-01-01

5

Laboratory Determination of Hydraulic Conductivity  

NSDL National Science Digital Library

From D.B. McWhorterand D. K. Sunda's 1977 Ground-Water Hydrology and Hydraulics, this two page excerpt outlines and details Laboratory Determination of Hydraulic Conductivity. Here, visitors will find illustrations and formula to understand the concept.

2008-02-07

6

Determination of the thermal conductivity of opalinus clay via simulations of experiments performed at the Mont Terri underground laboratory  

NASA Astrophysics Data System (ADS)

Storage in deep geological formations is a potential solution for the management of high-level radioactive wastes. In this context, different types of rocks such as argillite are extensively studied. In the Mont Terri underground laboratory (Switzerland), several experiments have been performed in order to characterize the properties of the opalinus clay. One of these experiments, called HE-C, has consisted in measuring in situ the time evolution of the rock temperature submitted to a heating source. Experimental measurements have shown that the thermal behaviour of the clay was not homogeneous around the borehole where the heater was installed. Furthermore, 3D direct numerical simulations of this experiment performed with the code Cast3M have proved that it was necessary to introduce a new parameter ? to model the amount of electric power lost in cables and by air convection inside the metallic tube containing the heater. A numerical simulation-optimization technique has been used to estimate the thermal longitudinal and transverse conductivities ( ?// and ??) of the host rock. It consists in minimizing an objective function that is the sum of the squared differences between measured and calculated temperatures. But this method induced a lot of Cast3M simulations. In order to drastically reduce the CPU time, we used a neural network approximation built from a sample training of 1100 Cast3M simulations. It allowed us to calculate the objective function for 500 000 different values of the triplet ( ?//, ??, ?). Finally, we obtained the following values for the thermal conductivities on one side of the borehole, ?// = 1.84 ± 0.04 W m - 1 K - 1 and ?? = 0.55 ± 0.03 W m - 1 K - 1 ; on the other side, ?// = 1.90 ± 0.07 W m - 1 K - 1 and ?? = 1.07 ± 0.09 W m - 1 K - 1 . The estimated thermal conductivities ?? perpendicular to the bedding plane are quite different. It is perhaps caused by the presence of an intensive fractured zone on one side of the borehole, due to bentonite swelling. It can also be due to the presence of a bed of carbonated rock.

Mügler, C.; Filippi, M.; Montarnal, Ph.; Martinez, J.-M.; Wileveau, Y.

2006-02-01

7

Laboratory experiments examine earthquake precursors  

NASA Astrophysics Data System (ADS)

Although it is not possible to predict when an earthquake will occur, many earthquakes have been found to have had some precursor activity. To study precursors of stick-slip behavior, Johnson et al. conducted laboratory experiments on a sheared granular material under normal stress ranging from 2 to 8 megapascals as an analog for a fault under tectonic stress. They found that acoustic emissions and microslips are a precursor to larger movements. Very similar results were obtained in a discrete element simulation of sheared beads. These types of experiments could help scientists better understand when earthquakes are more likely to occur. As shown by a number of researchers, very similar activity preceding faulting can occur in the Earth.

Balcerak, Ernie

2014-01-01

8

Conducting Miller-Urey Experiments  

NASA Technical Reports Server (NTRS)

In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials, using apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller introduced 200 ml of water, 100 mmHg of H2, 200mmHg of CH4, and 200mmHg of NH3 into the apparatus, then subjected this mixture, under reflux, to an electric discharge for a week, while the water was simultaneously heated. The purpose of this manuscript is to provide the reader with a general experimental protocol that can be used to conduct a Miller-Urey type spark discharge experiment, using a simplified 3 L reaction flask. Since the experiment involves exposing inflammable gases to a high voltage discharge, it is worth highlighting important steps that reduce the risk of explosion. The general procedures described in this work can be extrapolated to design and conduct a wide variety of electric discharge experiments simulating primitive planetary environments.

Parker, Eric Thomas; Cleaves, Henderson James; Burton, Aaron S.; Glavin, Daniel P.; Dworkin, Jason; Zhou, Manshui; Bada, Jeffrey L.; Fernandez, Facundo M.

2014-01-01

9

Beowulf Cluster Lab Laboratory Experience  

E-print Network

Beowulf Cluster Lab Laboratory Experience The Beowulf Cluster has 61 nodes: the master node is beowulf (also known as node00 inside the cluster), the compute nodes are node01, node02, . . ., node60 parallel programs. A more detailed users guide for the Beowulf Cluster Lab is at: http://cs.boisestate.edu/~amit/research/beowulf

Jain, Amit

10

Soap vs. Sanitizer Laboratory Experiment  

E-print Network

Soap vs. Sanitizer Laboratory Experiment #12;Why wash your hands? Hand are the most frequent and grease, which wash away with the water #12;What about hand sanitizer? When water is not available, hand sanitizer can be an effective alternative. The alcohol in hand sanitizer disrupts the coating on bacteria

Rose, Michael R.

11

Laboratory Electrical Conductivity Measurement of Mantle Minerals  

Microsoft Academic Search

Electrical conductivity structures of the Earth’s mantle estimated from the magnetotelluric and geomagnetic deep sounding\\u000a methods generally show increase of conductivity from 10?4–10?2 to 100 S\\/m with increasing depth to the top of the lower mantle. Although conductivity does not vary significantly in the lower\\u000a mantle, the possible existence of a highly conductive layer has been proposed at the base of

Takashi Yoshino

2010-01-01

12

Two LANL laboratory astrophysics experiments  

NASA Astrophysics Data System (ADS)

Two laboratory experiments are described that have been built at Los Alamos (LANL) to gain access to a wide range of fundamental plasma physics issues germane to astro, space, and fusion plasmas. The over arching theme is magnetized plasma dynamics which includes significant currents, MHD forces and instabilities, magnetic field creation and annihilation, sheared flows and shocks. The Relaxation Scaling Experiment (RSX) creates current sheets and flux ropes that exhibit fully 3D dynamics, and can kink, bounce, merge and reconnect, shred, and reform in complicated ways. Recent movies from a large data set describe the 3D magnetic structure of a driven and dissipative single flux rope that spontaneously self saturates a kink instability. Examples of a coherent shear flow dynamo driven by colliding flux ropes will also be shown.The Magnetized Shock Experiment (MSX) uses Field reversed configuration (FRC) experimental hardware that forms and ejects FRCs at 150km/sec. This is sufficient to drive a collision less magnetized shock when stagnated into a mirror stopping field region with Alfven Mach number MA=3 so that super critical shocks can be studied. We are building a plasmoid accelerator to drive Mach numbers MA >> 3 to access solar wind and more exotic astrophysical regimes. Unique features of this experiment include access to parallel, oblique and perpendicular shocks, shock region much larger than ion gyro radii and ion inertial length, room for turbulence, and large magnetic and fluid Reynolds numbers.*DOE Office of Fusion Energy Sciences under LANS contract DE-AC52-06NA25396, NASA Geospace NNHIOA044I, Basic, Center for Magnetic Self Organization

Intrator, Thomas; Weber, Thomas; Feng, Yan; Hutchinson, Trevor; Dunn, John; Akcay, Cihan

2014-06-01

13

Suspended sediment erosion in laboratory flume experiments  

E-print Network

Laboratory flume experiments are used to examine the role of suspended sediment abrasion in bedrock channel erosion. A range of topographies was used, from a planar bed to a sinuous and scalloped inner channel. Experiments ...

Cornell, Katrina Muir

2007-01-01

14

Fluid Flow Experiment for Undergraduate Laboratory.  

ERIC Educational Resources Information Center

The undergraduate fluid mechanics laboratory at Clarkson University consists of three experiments: mixing; drag measurements; and fluid flow and pressure drop measurements. The latter experiment is described, considering equipment needed, procedures used, and typical results obtained. (JN)

Vilimpochapornkul, Viroj; Obot, Nsima T.

1986-01-01

15

Laboratory Experience for Teaching Sensory Physiology  

ERIC Educational Resources Information Center

The major challenge in laboratory teaching is the application of abstract concepts in simple and direct practical lessons. However, students rarely have the opportunity to participate in a laboratory that combines practical learning with a realistic research experience. In the Bioengineering Department, we started an experiential laboratory

Albarracin, Ana L.; Farfan, Fernando D.; Felice, Carmelo J.

2009-01-01

16

Remote laboratory experiments in electrical engineering education  

Microsoft Academic Search

A remote or online laboratory is a laboratory where one can access experiments and instruments or other equipment from outside over the Internet. Laboratories for undergraduate education or vocational training in basic electrical engineering are easy to control remotely. One cannot see or hear the electrical current, so there is no need for sound or video transmission. Computer-based instruments do

Ingvar Gustavsson

2002-01-01

17

Multidimensional Screening as a Pharmacology Laboratory Experience.  

ERIC Educational Resources Information Center

A multidimensional pharmacodynamic screening experiment that addresses drug interaction is included in the pharmacology-toxicology laboratory experience of pharmacy students at the University of the Pacific. The student handout with directions for the procedure is reproduced, drug compounds tested are listed, and laboratory evaluation results are…

Malone, Marvin H.; And Others

1979-01-01

18

A laboratory experiment on the minority game  

NASA Astrophysics Data System (ADS)

This work presents experimental results on a coordination game in which agents must repeatedly choose between two sides, and a positive fixed payoff is assigned only to agents who pick the minoritarian side. We conduct laboratory experiments in which stationary groups of five players play the game for 100 periods, and manipulate two treatment variables: the amount of ‘memory’ M that players have regarding the game history (i.e., the length of the string of past outcomes that players can see on the screen while choosing) and the amount of information about other players’ past choices. Our results show that, at the aggregate level, a quite remarkable degree of coordination is achieved. Moreover, providing players with full information about other players’ choice distribution does not appear to improve efficiency significantly.

Bottazzi, Giulio; Devetag, Giovanna

2003-06-01

19

Internal wave tunnelling: Laboratory experiments  

NASA Astrophysics Data System (ADS)

Heuristics based upon ray theory are often used to predict the propagation of internal gravity waves in non-uniform media. In particular, they predict that waves reflect from weakly stratified regions where the local buoyancy frequency is less than the wave frequency. However, if the layer of weak stratification is sufficiently thin, waves can partially transmit through it in a process called tunnelling. The first laboratory evidence of internal wave tunnelling through a weakly stratified region is analysed using the synthetic schlieren technique and the Hilbert transform is applied to filter the wavefield into upward- and downward-propagating components. Transmission is calculated as the squared ratio of transmitted and incident wave amplitude and using an appropriate superposition of plane waves to reproduce the structure of the incident wave beam, a corresponding weighted sum of transmissions can be used to predict the beam transmission. These transmission predictions are compared with experimental measurements.

Gregory, Kate D.

20

CONDUCTIVITY PROFILE RATE OF CHANGE FROM FIELD AND LABORATORY DATA WITHIN BIODEGRADING PETROLEUM HYDROCARBON  

EPA Science Inventory

We present the results of long term (500 days) measurements of the bulk conductivity in a field and laboratory experiment. Our objective was to determine the rate of change in bulk conductivity and whether this rate of change correlated with the petroleum hydrocarbon degradation...

21

A Kinetic Experiment for the Biochemistry Laboratory.  

ERIC Educational Resources Information Center

Discusses the use of specific reactions of metabolic pathways to make measurements in the laboratory. Describes an adaptation of an experiment used in undergraduate biochemistry laboratories involving the induction of an enzyme in E. coli, as well as its partial purification and characterization. (TW)

Palmer, Richard E.

1986-01-01

22

Combustion experiments in a zero-gravity laboratory  

NASA Technical Reports Server (NTRS)

One of the payloads that the Shuttle will carry into low-earth orbit is the Spacelab, a laboratory designed by a European consortium which will enable scientist-astronauts to conduct research in a shirt-sleeve environment. The typical flight of seven days will permit numerous experiments to be conducted that take advantage of long-term reduced gravity. A description is presented of plans for the conduction of Spacelab experiments which are related to the study of combustion, taking into account also investigations performed in the preparation of such experiments. Attention is given to an overview study of combustion experiments in a space laboratory, droplet burning, flammability limits in a standard tube, the combustion of particle clouds, smoldering combustion in porous fuels, liquid pool burning, and combustion experimentation aboard the space transportation system.

Cochran, T. H.

1981-01-01

23

Argumentation in the Chemistry Laboratory: Inquiry and Confirmatory Experiments  

NASA Astrophysics Data System (ADS)

One of the goals of science education is to provide students with the ability to construct arguments—reasoning and thinking critically in a scientific context. Over the years, many studies have been conducted on constructing arguments in science teaching, but only few of them have dealt with studying argumentation in the laboratory. Our research focuses on the process in which students construct arguments in the chemistry laboratory while conducting various types of experiments. It was found that inquiry experiments have the potential to serve as an effective platform for formulating arguments, owing to the features of this learning environment. The discourse during inquiry-type experiments was found to be rich in arguments, whereas that during confirmatory-type experiments was found to be sparse in arguments. The arguments, which were developed during the discourse of an open inquiry experiment, focus on the hypothesis-building stage, analysis of the results, and drawing appropriate conclusions.

Katchevich, Dvora; Hofstein, Avi; Mamlok-Naaman, Rachel

2013-02-01

24

Cell biology experiments conducted in space  

NASA Technical Reports Server (NTRS)

A review of cell biology experiments conducted during the first two decades of space flight is provided. References are tabulated for work done with six types of living test system: isolated viruses, bacteriophage-host, bacteria, yeasts and filamentous fungi, protozoans, and small groups of cells (such as hamster cell tissue and fertilized frog eggs). The general results of studies involving the survival of cells in space, the effect of space flight on growing cultures, the biological effects of multicharged high-energy particles, and the effects of space flight on the genetic apparatus of microorganisms are summarized. It is concluded that cell systems remain sufficiently stable during space flight to permit experimentation with models requiring a fixed cell line during the space shuttle era.

Taylor, G. R.

1977-01-01

25

Laboratory experience for teaching sensory physiology  

NSDL National Science Digital Library

The major challenge in laboratory teaching is the application of abstract concepts in simple and direct practical lessons. However, students rarely have the opportunity to participate in a laboratory that combines practical learning with a realistic research experience. In the Bioengineering Department, we started an experiential laboratory physiology to teach graduated students some aspects of sensorial physiology and exposes them to laboratory skills in instrumentation and physiological measurements. Students were able to analyze and quantify the effects of activation of mechanoreceptors in multifiber afferent discharges using equipment that was not overly sophisticated. In consequence, this practical laboratory helps students to make connections with physiological concepts acquired in theoretical classes and to introduce them to electrophysiological research.

2009-06-01

26

Making Sparklers: An Introductory Laboratory Experiment.  

ERIC Educational Resources Information Center

Describes a basic introductory chemistry experiment for science majors which departs from synthesis and moves instead into the realm of formulation. As part of a project that reorganizes the introductory chemistry sequence according to subjects with which students are acquainted, this laboratory makes use of oxidation-reduction chemistry to make…

Keeney, Allen; Walters, Christina; Cornelius, Richard D.

1995-01-01

27

Microscale Experiments in the Organic Chemistry Laboratory.  

ERIC Educational Resources Information Center

Discusses the advent of microscale experiments within undergraduate organic chemistry laboratories mainly resulting from environmental safety concerns involving waste disposal. Considers the cost savings in purchasing less reagents and chemicals, the typical glassware and apparatus, the reduced hazards from elimination of open flames, and other…

Williamson, Kenneth L.

1991-01-01

28

Computer Based Simulation of Laboratory Experiments.  

ERIC Educational Resources Information Center

Examines computer based simulations of practical laboratory experiments in engineering. Discusses the aims and achievements of lab work (cognitive, process, psychomotor, and affective); types of simulations (model building and behavioral); and the strengths and weaknesses of simulations. Describes the development of a centrifugal pump simulation,…

Edward, Norrie S.

1997-01-01

29

Heat, Light, and Videotapes: Experiments in Heat Conduction Using Liquid Crystal Film.  

ERIC Educational Resources Information Center

Presents a range of experiments in heat conduction suitable for upper-level undergraduate laboratories that make use of heat sensitive liquid crystal film to measure temperature contours. Includes experiments mathematically described by Laplace's equation, experiments theoretically described by Poisson's equation, and experiments that involve…

Bacon, Michael E.; And Others

1995-01-01

30

Laboratory experiments of heat pump dynamic losses  

SciTech Connect

Air-source heat pump experiments at ORNL (1) provide detailed system and component performance data usable in understanding dynamic loss phenomena and (2) enable formulation and evaluation of methods that could reduce dynamic losses. Results presented herein are from series of laboratory experiments performed at ORNL aimed at providing detailed characterization of frosting losses, cycling losses, an defrosting losses as well as steady-state performance data. Continuous modulation heat pump experiments to observe dynamic loss trends under part-load heat pump operation will follow. 6 refs., 5 figs., 3 tabs.

Miller, W.A.

1984-01-01

31

The LUNA experiment at Gran Sasso Laboratory  

NASA Astrophysics Data System (ADS)

Accurate knowledge of thermonuclear reaction rates is a key issue in nuclear astrophysics since it is important for understanding the energy generation, neutrino production and the synthesis of the elements in stars. Cross-section measurements are mainly hampered by the very low counting rate and cosmic background. An underground location is extremely advantageous for such studies, as demonstrated by the LUNA experiment in the Gran Sasso Laboratory (Italy). This paper reports on the results recently obtained by such an experiment and on the future perspectives in this field.

Guglielmetti, Alessandra

2014-09-01

32

Monitoring hydraulic fracture growth: Laboratory experiments  

SciTech Connect

The authors carry out small-scale hydraulic fracture experiments to investigate the physics of hydraulic fracturing. The laboratory experiments are combined with time-lapse ultrasonic measurements with active sources using both compressional and shear-wave transducers. For the time-lapse measurements they focus on ultrasonic measurement changes during fracture growth. As a consequence they can detect the hydraulic fracture and characterize its shape and geometry during growth. Hence, this paper deals with fracture characterization using time-lapse acoustic data. Hydraulic fracturing is used in the oil and gas industry to stimulate reservoir production.

Groenenboom, J.; Dam, D.B. van

2000-04-01

33

Automatic counting of collembolans for laboratory experiments  

Microsoft Academic Search

A new procedure involving digital image processing and image analysis for determination of the number of individuals and size distribution of a collembolan population is presented. It is applicable to experiments conducted with a single species either on plaster or in soil. Collembolans are transferred to an even, black surface and immobilised by anaesthetisation with carbon dioxide. By scanning the

Paul Henning Krogh; Kent Johansen; Martin Holmstrup

1998-01-01

34

Laboratory capacity modulation experiments, analyses and validation  

SciTech Connect

A combined experimental and analytical project was conducted on a breadboarded continuously variable speed air-to-air heat pump (CVSHP). The split-system residential unit of nominal 2-3/4-ton (9. 7-kW) cooling capacity was instrumented and tested in environmental chambers. The steady-state, frosting/demand defrosting, and cycling efficiency characteristics of the CVSHP with first generation components (e.g., heat exchangers, compressor, and indoor blower, both having variable speed induction motors) were measured in the laboratory for compressor drive frequencies ranging from 15 through 90 Hz. Steady-state efficiency data were used to validate an initial version of the Oak Ridge National Laboratory steady-state modulating heat pump design program. Algorithms were developed from reduced dynamic loss data from which calculations were made of the seasonal losses for the test CVSHP. 18 refs., 10 figs., 5 tabs.

Miller, W.A.

1988-01-01

35

Weld Tests Conducted by the Idaho National Laboratory  

SciTech Connect

During the fiscal year of 2006, the Idaho National Laboratory (INL) performed many tests and work relating to the Mobile Melt-Dilute (MMD) Project components. Tests performed on the Staubli quick disconnect fittings showed promising results, but more tests were needed validate the fittings. Changes were made to the shield plug design—reduced the closure groove weld depth between the top of the canister and the top plate of the shielding plug from 0.5-in to 0.375-in deep. Other changes include a cap to cover the fitting, lifting pintle and welding code citations on the prints. Tests conducted showed stainless steel tubing, with 0.25-in, 0.375-in, and 0.5-in diameters, all with 0.035-in wall thickness, could be pinch seal welded using commercially available resistance welding equipment. Subsequent testing showed that these welds could be real-time inspected with ultrasonic inspection methods.

Larry Zirker; Lance Lauerhass; James Dowalo

2007-02-01

36

Conductance of Ion Channels - Theory vs. Experiment  

NASA Technical Reports Server (NTRS)

Transmembrane ion channels mediate a number of essential physiological processes in a cell ranging from regulating osmotic pressure to transmission of neural signals. Kinetics and selectivity of ion transport is of critical importance to a cell and, not surprisingly, it is a subject of numerous experimental and theoretical studies. In this presentation we will analyze in detail computer simulations of two simple channels from fungi - antiamoebin and trichotoxin. Each of these channels is made of an alpha-helical bundle of small, nongenomically synthesized peptides containing a number of rare amino acids and exhibits strong antimicrobial activity. We will focus on calculating ionic conductance defined as the ratio of ionic current through the channel to applied voltage. From molecular dynamics simulations, conductance can be calculated in at least two ways, each involving different approximations. Specifically, the current, given as the number of charges transferred through the channel per unit of time, can be obtained from the number of events in which ions cross the channel during the simulation. This method works well for large currents (high conductance values and/or applied voltages). If the number of crossing events is small, reliable estimates of current are difficult to achieve. Alternatively, conductance can be estimated assuming that ion transport can be well approximated as diffusion in the external potential given by the free energy profile. Then, the current can be calculated by solving the one-dimensional diffusion equation in this external potential and applied voltage (the generalized Nernst-Planck equation). To do so three ingredients are needed: the free energy profile, the position-dependent diffusion coefficient and the diffusive flux of ions into the channel. All these quantities can be obtained from molecular dynamics simulations. An important advantage of this method is that it can be used equally well to estimating large and small currents. In addition, once the free energy profile becomes available the full current-voltage dependence can be readily obtained. For both channels we carried out calculations using both approaches. We also tested the main assumptions underlying the diffusive model, such as uncorrelated nature of individual crossing events and Fickian diffusion. The accuracy and consistency of different methods will be discussed. Finally we will discuss how comparisons between calculated and measured ionic conductance and selectivity of transport can be used for determining structural models of the channels.

Pohorille, Andrew; Wilson, Michael; Mijajlovic, Milan

2013-01-01

37

Thermal-blooming laboratory experiments. (Reannouncement with new availability information)  

SciTech Connect

The authors conducted a multiphase series of laboratory experiments to explore the adaptive optics compensation of a laser beam distorted by strong thermal blooming. Their experimental approach was to create on a small, low-power beam the same phase distortion that would be experienced by a large, high-power beam propagating through the atmosphere and to apply phase compensation via deformable mirrors. The authors performed the investigations to lay the foundation for future ground-based laser experiments and their corresponding atmospheric-propagation computer models.

Johnson, B.

1992-12-31

38

Experiment definition phase shuttle laboratory. LDRL-10.6 experiment  

NASA Technical Reports Server (NTRS)

The work completed on the experiment definition phase of the shuttle laboratory LDRL 10.6 micrometers experiment from 27 September 1975 to 26 January 1976 was reported. This work included progress in the following areas: (1) optomechanical system: completion of detail drawings, completion of the beryllium subassembly, fabrication, checking, and weighing of approximately 95% of the detailed parts, dry film lubrication of the bearings and gears, and initiation of assembly of the gimbals; (2) optics: update of the detailed optical layout, receipt of nine mirrors and the pre-expander; (3) miscellaneous: delivery of draft material for the final report, completion of optical testing of the 10.6 micrometers receiver, and receipt, assembly, and checkout of NASA test console.

1976-01-01

39

GUIDELINES FOR CONDUCTING SINGLE LABORATORY EVALUATIONS OF BIOLOGICAL METHODS  

EPA Science Inventory

The single laboratory test is used to establish the data quality that can be achieved within a single laboratory. It provides a basis for deciding whether or not a given method merits collaborative testing and it more clearly defines a method's potential for inclusion as part of ...

40

Laboratory-scale fracture conductivity created by acid etching  

E-print Network

Success of acid fracturing treatment depends greatly on the created conductivity under closure stress. In order to have sufficient conductivity, the fracture face must be non-uniformly etched while the fracture strength maintained to withstand...

Pournik, Maysam

2009-05-15

41

Meteorological Development Laboratory Student Career Experience Program  

NASA Astrophysics Data System (ADS)

The National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the protection of life and property and the enhancement of the national economy. The NWS's Meteorological Development Laboratory (MDL) supports this mission by developing meteorological prediction methods. Given this mission, NOAA, NWS, and MDL all have a need to continually recruit talented scientists. One avenue for recruiting such talented scientist is the Student Career Experience Program (SCEP). Through SCEP, MDL offers undergraduate and graduate students majoring in meteorology, computer science, mathematics, oceanography, physics, and statistics the opportunity to alternate full-time paid employment with periods of full-time study. Using SCEP as a recruiting vehicle, MDL has employed students who possess some of the very latest technical skills and knowledge needed to make meaningful contributions to projects within the lab. MDL has recently expanded its use of SCEP and has increased the number of students (sometimes called co- ops) in its program. As a co-op, a student can expect to develop and implement computer based scientific techniques, participate in the development of statistical algorithms, assist in the analysis of meteorological data, and verify forecasts. This presentation will focus on describing recruitment, projects, and the application process related to MDL's SCEP. In addition, this presentation will also briefly explore the career paths of students who successfully completed the program.

McCalla, C., Sr.

2007-12-01

42

Patient's dissatisfaction with the public and private laboratory services in conducting HIV related testing in Tanzania  

Microsoft Academic Search

BACKGROUND: Patient's satisfaction with both private and public laboratory services is important for the improvement of the health care delivery in any country. METHODS: A cross-sectional survey was conducted in 24 randomly selected health facilities with laboratories that are conducting HIV related testing, in Mainland Tanzania. The study assessed patient's satisfaction with the laboratory services where by a total of

SG Mfinanga; A Kahwa; G Kimaro; A Kilale; S Kivuyo; M Senkoro; B Ngowi; R Mtandu; B Mutayoba; E Ngadaya; K Mashoto

2008-01-01

43

A Cooperative University-High School Modern Physics Laboratory Experience.  

ERIC Educational Resources Information Center

Described is an extracurricular program for high school students in which they visited a college physics laboratory facility and participated in laboratory activities. Discussed are the planning, student experiences, and results. (CW)

Austen, David; And Others

1991-01-01

44

An Experiment in Heat Conduction Using Hollow Cylinders  

ERIC Educational Resources Information Center

An experimental apparatus was designed and built to allow students to carry out heat conduction experiments in hollow cylinders made of different materials, as well as to determine the thermal conductivity of these materials. The evolution of the temperature difference between the inner and outer walls of the cylinder as a function of time is…

Ortuno, M.; Marquez, A.; Gallego, S.; Neipp, C.; Belendez, A.

2011-01-01

45

Do-It-Yourself Experiments for the Instructional Laboratory  

ERIC Educational Resources Information Center

A new design for experiments in the general chemistry laboratory incorporates a "do-it-yourself" component for students. In this design, students perform proven experiments to gain experience with techniques for about two-thirds of a laboratory session and then spend the last part in the do-it-yourself component, applying the techniques to an…

Craig, Norman C.; Hill, Cortland S.

2012-01-01

46

Operational Amplifier Experiments for the Chemistry Laboratory.  

ERIC Educational Resources Information Center

Provides details of experiments that deal with the use of operational amplifiers and are part of a course in instrumental analysis. These experiments are performed after the completion of a set of electricity and electronics experiments. (DDR)

Braun, Robert D.

1996-01-01

47

Conducting a Teaching Experiment with a Gifted Student  

ERIC Educational Resources Information Center

In this study, the teaching experiment methodology is used to observe firsthand a gifted student's mathematical learning and reasoning. A series of teaching experiments was conducted with 1 gifted and 1 average 7th-grade student to investigate how the gifted student's mathematical concepts and operation constructions differed from those of the…

Hekimoglu, Serkan

2004-01-01

48

Laboratory Experiments for Network Security Instruction  

ERIC Educational Resources Information Center

We describe a sequence of five experiments on network security that cast students successively in the roles of computer user, programmer, and system administrator. Unlike experiments described in several previous papers, these experiments avoid placing students in the role of attacker. Each experiment starts with an in-class demonstration of an…

Brustoloni, Jose Carlos

2006-01-01

49

Laboratory Experiments and Hydrodynamic Modeling of a Bed Leveler Used to Level the Bottom of Ship Channels after Dredging  

E-print Network

This study was conducted to ascertain the impacts of bed leveling, following ship channel dredging operations, and to also investigate the hydrodynamic flow field around box bed levelers. Laboratory experiments were conducted with bed levelers...

Paul, Ephraim Udo

2011-02-22

50

Brownian Motion--a Laboratory Experiment.  

ERIC Educational Resources Information Center

Introduces an experiment involving the observation of Brownian motion for college students. Describes the apparatus, experimental procedures, data analysis and results, and error analysis. Lists experimental techniques used in the experiment. Provides a circuit diagram, typical data, and graphs. (YP)

Kruglak, Haym

1988-01-01

51

Collaborative learning experience in a freshman materials laboratory exercise  

Microsoft Academic Search

Freshmen students are often treated as incapable of operating without carefully detailed instructions for many types of laboratory experiences. At Purdue-Kokomo, six different laboratory exercises are provided for our freshmen taking the initial course in Materials and Processing, MET 141. In the past, detailed written laboratory instructions were provided, spelling out exactly how to make the necessary measurements, how to

J. R. Williams

1995-01-01

52

A laboratory helicity injection perspective of plasma jet formation by a conducting Keplerian accretion disk  

NASA Astrophysics Data System (ADS)

A conducting accretion disk in a plasma environment makes a natural dynamo machine that converts the orbital mechanical energy into an expanding magnetic jet/lobe via magnetic helicity injection by differentially twisting a magnetic arcade line-tied on the disk. In the laboratory, a radial electric field imposed by co-axial electrodes faithfully simulates the same process by drawing current from a power supply to run through a plasma threaded by an externally imposed poloidal field. The toroidal magnetic flux is then injected by the current into the discharge chamber, driving a magnetic bubble expansion. Laboratory applications range from spheromak formation to non-inductive current drive in spherical Tokamaks. The helicity injection physics that underlies the collimated extra-galactic jet/lobes shares many similar challenges with those of laboratory fusion applications, but with a number of new twists. Theoretical and 3D MHD computational studies will be presented to clarify: (1) the collimation mechanism for an under- and over-pressured jet, and the physical mechanism for driving plasmas away from the central object; (2) the helicity and energy content of the jet, and the partition between kinetic and magnetic energy; (3) the stability characteristics of freely-expanding and stagnated jets. Much of our results have been given in terms of dimensionless parameters, the critical boundaries of which can be accessed in carefully designed laboratory experiments. Work supported by LANL LDRD funds.

Tang, Xianzhu

2004-11-01

53

Astrophysical jets: Observations, numerical simulations, and laboratory experiments  

SciTech Connect

This paper provides summaries of ten talks on astrophysical jets given at the HEDP/HEDLA-08 International Conference in St. Louis. The talks are topically divided into the areas of observation, numerical modeling, and laboratory experiment. One essential feature of jets, namely, their filamentary (i.e., collimated) nature, can be reproduced in both numerical models and laboratory experiments. Another essential feature of jets, their scalability, is evident from the large number of astrophysical situations where jets occur. This scalability is the reason why laboratory experiments simulating jets are possible and why the same theoretical models can be used for both observed astrophysical jets and laboratory simulations.

Bellan, P. M. [Caltech, Pasadena, California 91125 (United States); Livio, M. [Space Telescope Science Institute, Baltimore, Maryland 21218 (United States); Kato, Y. [University of Tsukuba, Ibaraki 3058577 (Japan); Lebedev, S. V. [Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom); Ray, T. P. [Dublin Institute for Advanced Studies, 5 Merrion Square, Dublin 2 (Ireland); Ferrari, A. [Dipartimento di Fisica, Universita di Torino, via Pietro Giuria 1, 10125 Torino, Italy and Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637 (United States); Hartigan, P. [Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892 (United States); Frank, A. [Department of Physics and Astronomy and Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627 (United States); Foster, J. M. [AWE Aldermaston, Reading RG7 4PR (United Kingdom); Nicolaie, P. [Centre Lasers Intenses et Applications, Universite Bordeaux 1-CEA-CNRS, 33405 Talence (France)

2009-04-15

54

Experiences of mentors training underrepresented undergraduates in the research laboratory.  

PubMed

Successfully recruiting students from underrepresented groups to pursue biomedical science research careers continues to be a challenge. Early exposure to scientific research is often cited as a powerful means to attract research scholars with the research mentor being critical in facilitating the development of an individual's science identity and career; however, most mentors in the biological sciences have had little formal training in working with research mentees. To better understand mentors' experiences working with undergraduates in the laboratory, we conducted semistructured interviews with 15 research mentors at a public university in the Midwest. The interviewed mentors were part of a program designed to increase the number of American Indians pursuing biomedical/biobehavioral research careers and represented a broad array of perspectives, including equal representation of male and female mentors, mentors from underrepresented groups, mentors at different levels of their careers, and mentors from undergraduate and professional school departments. The mentors identified benefits and challenges in being an effective mentor. We also explored what the term underrepresented means to the mentors and discovered that most of the mentors had an incomplete understanding about how differences in culture could contribute to underrepresented students' experience in the laboratory. Our interviews identify issues relevant to designing programs and courses focused on undergraduate student research. PMID:24006389

Prunuske, Amy J; Wilson, Janelle; Walls, Melissa; Clarke, Benjamin

2013-01-01

55

Laboratory Experiences in Marine Biology, Student Edition.  

ERIC Educational Resources Information Center

This manual contains instructions for laboratory exercises using marine organisms. For each exercise a problem is defined, materials are listed, possible ways to solve the problem are suggested, questions are asked to guide the student in interpreting data, and further reading is suggested. The exercises deal with the measurement of oxygen…

Raimist, Roger J.

56

Linking Laboratory Experiences to the Real World: The Extraction of Octylphenoxyacetic Acid from Water  

ERIC Educational Resources Information Center

Several chemical concepts to the extraction of a water pollutant OPC (octylphenoxyacetic acid) is presented. As an introduction to the laboratory experiment, a discussion on endocrine disrupters is conducted to familiarize the student with the background of the experiment and to explain the need for the extraction and quantitation of the OPC which…

Loyo-Rosales, Jorge E.; Torrents, Alba; Rosales-Rivera, Georgina C.; Rice, Clifford C.

2006-01-01

57

Laboratory hydraulic fracturing experiments in intact and pre-fractured rock  

Microsoft Academic Search

Laboratory hydraulic fracturing experiments were conducted to investigate two factors which could influence the use of the hydrofrac technique for in-situ stress determinations; the possible dependence of the breakdown pressure upon the rate of borehole pressurization, and the influence of pre-existing cracks on the orientation of generated fractures. The experiments have shown that while the rate of borehole pressurization has

M. D. Zoback; R. Rummel; R. Jung; C. B. Raleigh

1977-01-01

58

Contributions of orbital mechanics to conducting experiments in space  

NASA Technical Reports Server (NTRS)

Orbital mechanics as a discipline is principally concerned with solving the set of equations for analyzing the motion of a satellite under various conditions. This activity on the surface may not seem crucial to conducting experiments in space, but it provides insights into the way in which forces may influence these experiments. More directly, for experiments concerned with external targets, it provides predictions of the satellites's position and velcoity verus time, enabling extensive preflight planning and resulting in optimum use of on-orbit time.

Mullins, L. D.

1981-01-01

59

Some Significant Experiments in Vocational Training. (Surveys Conducted in 1977).  

ERIC Educational Resources Information Center

A symposium was held to discuss the question, How and to what extent is technical and vocational education in Europe encouraging occupational mobility? Following the symposium, a series of visits was conducted to view innovative practices and experiments concerning this question; countries visited included Belgium, Switzerland, the United Kingdom,…

Council for Cultural Cooperation, Strasbourg (France).

60

Inventory Control. Easily Made Electronic Device for Conductivity Experiments.  

ERIC Educational Resources Information Center

Describes how to construct an electronic device to be used in conductivity experiments using a 35 millimeter film canister, nine volt battery replacement snaps, a 200-300 ohm resistor, and a light-emitting diode. Provides a diagram and photographs of the device. (TW)

Gadek, Frank J.

1987-01-01

61

Students Designing their Own Laboratory Experiments - The Experience of 4 Semesters  

Microsoft Academic Search

An undergraduate environmental engineering laboratory class was revised in Fall 1999 to include an open experiment in a ddition to traditional experiments. Each student group identified a problem, designed an experiment to address the problem, performed the experiment, and documented the results with laboratory reports. A variety of topics were selected, including remediation of acid mine drainage and evaluating indoor

Joseph R. V. Flora; Adrienne T. Cooper

62

Integrated verification experiment data collected as part of the Los Alamos National Laboratory`s Source Region program. Appendix F: Regional data from Lawrence Livermore National Laboratory and Sandia National Laboratory Seismic Networks  

SciTech Connect

A dataset of regional seismograms assembled for a series of Integrated Verification Experiments conducted by the Los Alamos National Laboratory Source Region program is described. The seismic data has been assembled from networks operated by Lawrence Livermore National Laboratory and Sandia National Laboratory. Examples of the data are shown and basic recording characteristics of the network are described. The seismograms are available on a data tape in SAC format upon request.

Taylor, S.R.

1993-06-11

63

LABORATORY EXPERIMENT 4 Alkalimetric Titration of an Acid Mixture  

E-print Network

LABORATORY EXPERIMENT 4 Alkalimetric Titration of an Acid Mixture In this experiment the quantitative composition of a solution, which is a mixture of a monoprotic strong acid (HCl) and a weaker triprotic acid (H3PO4) will be determined by pH- potentiometric methods. This experiment will introduce you

Nazarenko, Alexander

64

Crepuscular rays: laboratory experiments and simulations.  

PubMed

Model simulations of laboratory-generated and natural crepuscular rays are presented. Rays are created in the laboratory with parallel light beams that pass through artificial fogs and milk-water solutions. Light scattered by 90° in a dilute mixture of whole milk first increases in intensity with distance from the source to a maximum as a result of multiple scattering by mainly small angles before decreasing exponentially due to extinction as distance continues to increase. Crepuscular rays are simulated for three cloud configurations. In case 1, the Sun at the zenith is blocked by a cloud with an overhanging anvil. The rays appear white against blue sky and are brightest when atmospheric turbidity, ??11. Shading by the anvil separates maximum brightness from apparent cloud edge. In case 2, a ray passes through a rectangular gap in a cloud layer. The ray is faint blue in a molecular atmosphere but turns pale yellow as ? and solar zenith angle, ?(sun), increase. At ?(sun)=60° it appears most striking when the cloud is optically thick, ??5, and the beam width ?x?1000 m. In these cases, increasing aerosol radius, r(aer), to about 1000 nm brightens, narrows, and shortens rays. In case 3, the twilight Sun is shaded by a towering cloud or mountain. The shaded rays are deeper blue than the sunlit sky because the light originates higher in the atmosphere, where short waves have suffered less depletion from scattering. The long optical path taken by sunlight at twilight makes color and lighting contrasts of the rays greatest when the air is quite clean, i.e., for ?-1?1. In all cases, the brightest rays occur when sunlight passes through an optical thickness of atmosphere, ??O(1). PMID:22016238

Gedzelman, Stanley David; Vollmer, Michael

2011-10-01

65

Symmetron dark energy in laboratory experiments.  

PubMed

The symmetron scalar field is a matter-coupled dark energy candidate which effectively decouples from matter in high-density regions through a symmetry restoration. We consider a previously unexplored regime, in which the vacuum mass ?~2.4×10(-3) eV of the symmetron is near the dark energy scale, and the matter coupling parameter M~1 TeV is just beyond standard model energies. Such a field will give rise to a fifth force at submillimeter distances which can be probed by short-range gravity experiments. We show that a torsion pendulum experiment such as Eöt-Wash can exclude symmetrons in this regime for all self-couplings ? is < or approximately equal to 7.5. PMID:23373910

Upadhye, Amol

2013-01-18

66

LABORATORY EXPERIMENT 7 The Iodometric Determination of Copper in Brass  

E-print Network

LABORATORY EXPERIMENT 7 The Iodometric Determination of Copper in Brass Discussion The method is relatively simple and applicable to brasses with less than 2% iron. A weighed sample is treated with nitric

Nazarenko, Alexander

67

Laboratory Experiments on the Electrochemical Remediation of the Environment  

ERIC Educational Resources Information Center

Ferrate, which is a strong iron oxidant for removing pollutants from water, is developed electrochemically in the laboratory, and used for experiments simulating environmental situations. Thus, ferrate is a powerful oxidizing agent capable of destroying an immense variety of contaminants.

Ibanez, Jorge G.; Tellez-Giron, Monica; Alvarez, Diana

2004-01-01

68

High Performance Liquid Chromatography Experiments to Undergraduate Laboratories  

ERIC Educational Resources Information Center

Reviews the principles of liquid chromatography with electrochemical detection (LCEC), an analytical technique that incorporates the advantages of both liquids chromatography and electrochemistry. Also suggests laboratory experiments using this technique. (MLH)

Kissinger, Peter T.; And Others

1977-01-01

69

First experiences with the rotating laboratory  

NASA Technical Reports Server (NTRS)

This report describes experiences with a rotating cylinder to explore the effects of motion and flow upon human sensory organs. One observation was that the variation of the resultant line of gravity (from gravity and centrifugal force) was not felt so strongly as might be expected. The impressions produced by the physical effects on the members of the body, especially the ones caused by the deflecting force (Coriolis force), are exactly what the laws of physics would lead us to expect, although somewhat surprising when observed in one's own body.

Prandtl, L

1926-01-01

70

Traditional Laboratory Exercises and Remote Experiments in Electrical Engineering Education  

Microsoft Academic Search

Laboratory work is recognized as an efficient method for students to assimilate knowledge and to develop skills for solving real world problems. The Internet provides new opportunities for remote experimentation. Laboratory exercises in electrical engineering courses such as circuit theory and basic electronics can be performed remotely using real equipment. What equipment is required for remote experiments? Is it possible

Ingvar Gustavsson

71

Agreed Discoveries: Students' Negotiations in a Virtual Laboratory Experiment  

ERIC Educational Resources Information Center

This paper presents an analysis of the scientific reasoning of a dyad of secondary school students about the phenomenon of dissolution of gases in water as they work on this in a simulated laboratory experiment. A web-based virtual laboratory was developed to provide learners with the opportunity to examine the influence of physical factors on gas…

Karlsson, Goran; Ivarsson, Jonas; Lindstrom, Berner

2013-01-01

72

Fertilizers mobilization in alluvial aquifer: laboratory experiments  

NASA Astrophysics Data System (ADS)

In alluvial plains, intensive farming with conspicuous use of agrochemicals, can cause land pollution and groundwater contamination. In central Po River plain, paleo-channels are important links between arable lands and the underlaying aquifer, since the latter is often confined by clay sediments that act as a barrier against contaminants migration. Therefore, paleo-channels are recharge zones of particular interest that have to be protected from pollution as they are commonly used for water supply. This paper focuses on fertilizer mobilization next to a sand pit excavated in a paleo-channel near Ferrara (Italy). The problem is approached via batch test leaking and columns elution of alluvial sediments. Results from batch experiments showed fast increase in all major cations and anions, suggesting equilibrium control of dissolution reactions, limited availability of solid phases and geochemical homogeneity of samples. In column experiments, early elution and tailing of all ions breakthrough was recorded due to preferential flow paths. For sediments investigated in this study, dispersion, dilution and chemical reactions can reduce fertilizers at concentration below drinking standards in a reasonable time frame, provided fertilizer loading is halted or, at least, reduced. Thus, the definition of a corridor along paleo-channels is recommended to preserve groundwater quality.

Mastrocicco, M.; Colombani, N.; Palpacelli, S.

2009-02-01

73

Experiment definition phase shuttle laboratory LDRL 10.6 experiment  

NASA Technical Reports Server (NTRS)

System optimization is reported along with mission and parameter requirements. Link establishment and maintenance requirements are discussed providing an acquisition and tracking scheme. The shuttle terminal configurations are considered and are included in the experiment definition.

1974-01-01

74

The JPL MSAT mobile laboratory and the pilot field experiments  

NASA Technical Reports Server (NTRS)

A Mobile Laboratory/Propagation Measurement Van (PMV) was developed to support the field experiments of the Mobile Satellite Experiment (MSAT-X) Project. This van was designed to provide flexibility, self-sufficiency and data acquisition to allow for both measurement of equipment performance and the mobile environment. The design philosophy and implementation of the PMV are described. The Pilot Field Experiments and an overall description of the three experiments in which the PMV was used are described.

Berner, Jeff B.; Emerson, Richard F.

1988-01-01

75

Establishing laboratory standards for biological flight experiments  

NASA Technical Reports Server (NTRS)

The general objective of this research was to assess the effects of exposure to simulated microgravity on ultrastructural aspects of the contractile system in chicken skeletal muscle cells. This general objective had two specific experimental components: (1) the progression of changes in cell morphology, fusion, and patterns of contractile filament organization in muscle cell cultures grown in hollow fibers in the Clinostat were evaluated, with appropriate controls; (2) to initiate experiments in which muscle cells were grown on the surface of microcarrier beads. The ultimate objective of this second portion of the work is to determine if these beads can be rotated in a bioreactor and thereby obtain a more accurate approximation of the effects of simulated microgravity on differentiated muscle cells.

Young, Ronald B.; Moriarity, Debra M.

1989-01-01

76

Laboratory and Field Measurements of Soil Bulk Electrical Conductivity Using Time Domain Reflectometry  

NASA Astrophysics Data System (ADS)

As the increasing of contamination in soil and groundwater, there is a demand for fast, accurate, and cost-effective techniques for contaminated site investigation. Time domain reflectometry (TDR) is a nondestructive geophysical method that allows, in real time, simultaneous estimation of both the dielectric constant and the bulk soil electrical conductivity (EC). On such bases, TDR is a technique that could potentially be adapted for continuous monitoring of solute contaminants in soil and water. The objective of this study is to assess the performance of TDR for estimating the EC and the solute concentration through the laboratory experiments and then applied it to a field of mercury contamination in the sediments. Measurement of EC using TDR is based on the attenuation of the applied voltage as it traverses the medium of interest. Once the geometric constant of the probe can be determined and the mismatch of the TDR instrument can be corrected during the experimental setup, EC can easily be accurately evaluated through a single TDR measurement on the considered sample. The results obtained from the laboratory experiments showed the good agreement between the TDR measurement and conductivity meter, and the linear relationship between EC and solute concentration is also validated. Given a specific concentration of solution, the decrease of EC with the decrease of water content followed Archie's law. Experiments with releasing a pulse and continuous potassium nitrate solutions into a soil column were conducted to demonstrate the TDR capability of real time monitoring. The results showed that the breakthrough curve (BC) can be accurately and clearly delineated by the TDR measurement. In this study, the TDR application was also extended to a contaminated site in southern Taiwan. The mercury contaminated sediments were deposited at the bottom of saline lakes and the TDR probes were modified to overcome the measurement under the water. The field work showed that the spatial distribution of relative-high mercury concentrations could be identified by TDR. Although the absolute mercury concentration is still undetermined, but the feasibility of using TDR as a reference tool for contaminant site investigation and self-assessment of remediation was successfully demonstrated.

Hsu, S.; Chiu, Y.

2013-12-01

77

Impact cratering in viscous targets - Laboratory experiments  

NASA Technical Reports Server (NTRS)

To determine the effects of target yield strength and viscosity on the formation and morphology of Martian multilobed, slosh and rampart-type impact craters, 75 experiments in which target properties and impact energies were varied were carried out for high-speed motion picture observation in keeping with the following sequence: (1) projectile initial impact; (2) crater excavation and rise of ejecta plume; (3) formation of a transient central mound which generates a surge of material upon collapse that can partly override the plume deposit; and (4) oscillation of the central mound with progressively smaller surges of material leaving the crater. A dimensional analysis of the experimental results indicates that the dimensions of the central mound are proportional to (1) the energy of the impacting projectile and (2) to the inverse of both the yield strength and viscosity of the target material, and it is determined that extrapolation of these results to large Martian craters requires an effective surface layer viscosity of less than 10 to the 10th poise. These results may also be applicable to impacts on outer planet satellites composed of ice-silicate mixtures.

Greeley, R.; Fink, J.; Snyder, D. B.; Gault, D. E.; Guest, J. E.; Schultz, P. H.

1980-01-01

78

Carbonatisation of Weathered Peridotites in Laboratory Experiments  

NASA Astrophysics Data System (ADS)

Enhanced in-situ carbonatisation of ultramafic rocks has been proposed as a strategy for a permanent and safe storage of CO2 in order to reduce anthropogenic greenhouse gas emissions (e.g., Kelemen and Matter 2008). This idea emerged from studies of natural examples demonstrating that ultramafic rocks react extensively with CO2 to form ophicarbonates. However, despite their Mg-rich nature, ultramafic rocks are often associated with calcite (CaCO3) rather than magnesite (MgCO3) and dolomite (CaMg(CO3)2). Whether these so-called ophicalcites represent sedimentary or tectonic breccias or are produced during hydrothermal alteration of ultramafic rocks, has been discussed for many years (e.g., Folk and McBride 1976). The view that reactions between hydrothermal fluids and ultramafic rocks can result in the formation of ophicalcite was recently supported by Beinlich et al. (2010), who documented Ca- and CO2-metasomatism and extreme Mg depletion in serpentinised and weathered peridotite clasts from the conglomerates of the Solund basin (SW Norway). This study also suggests that weathering is an important factor for the carbonatisation of ultramafic rocks. We have performed hydrothermal experiments on weathered peridotites in order to better constrain the mechanisms and conditions that trigger Mg-loss from ultramafic rocks and subsequent calcite precipitation. Un-crushed, partly serpentinised and weathered peridotite samples were allowed to react in a Ca-bearing saline solution under CO2 pressure (PCO2: 130-160 bar) at 200°C. We were able to illustrate the textural and chemical evolution during the reaction through a detailed comparison of the solid and fluid samples before and after the experiments. The initial samples showed a typical mesh texture with veins of serpentine surrounding meshes filled either with fresh or weathered olivine. The experimentally treated samples reveal a strongly reacted rim, predominantly composed of calcite, but still showing ghosts of the former mesh texture. Meshes that were initially filled with weathered olivine, were preferred sites of reaction relative to fresh olivine and serpentine. Dissolution of the mesh fillings and subsequent replacement by calcite resulted in Mg- and Si-enrichment in the fluid. The results confirm that hydrothermal alteration of ultramafic rocks may lead to Mg-depletion and ophicalcite formation and, in particular, highlight the role of weathering in enhancing the carbonatisation of peridotites. Our study has potential implications for industrial mineral sequestration of CO2 since weathering is commonly extensive in peridotites. The removal of Mg from the site of carbonatisation would be an undesired effect during CO2 injection into ultramafic rocks, but with a Ca-source available carbonatisation may still be effective. References: Beinlich, A., Austrheim, H., Glody, J., Erambert, M. and Andersen, T.B. (2010), Geochim. Cosmochim. Acta, in press. Folk, R.L. and McBride, E.F. (1976), Geology, 4(6): 327-332. Kelemen, P.B. and Matter, J. (2008), PNAS, 105(45): 17295-17300.

Hövelmann, J.; Austrheim, H.; Beinlich, A.; Munz, I. A.

2010-12-01

79

Laboratory Experience in Outdoor Education. Senior Student Teaching Experience.  

ERIC Educational Resources Information Center

This guide describes the outdoor education practicum required of student teachers at Northern Illinois University (NIU). This 5-day residential experience is held at the Lorado Taft Field Campus (branch of NIU), established in 1951 to train teachers in outdoor education. Course objectives include: (1) to help student teachers gain knowledge about…

Northern Illinois Univ., Oregon. Lorado Taft Field Campus.

80

Does the Lack of Hands-On Experience in a Remotely Delivered Laboratory Course Affect Student Learning?  

ERIC Educational Resources Information Center

Educators question whether performing a laboratory experiment as an observer (non-hands-on), such as conducted in a distance education context, can be as effective a learning tool as personally performing the experiment in a laboratory environment. The present paper investigates this issue by comparing the performance of distance education…

Abdel-Salam, Tarek; Kauffman, Paul J.; Crossman, Gary

2006-01-01

81

Innovative research and laboratory experiences for undergraduate students  

Microsoft Academic Search

Students majoring in Engineering Technology programs at Western Washington University (USA) have many opportunities to participate in unique undergraduate research experiences and innovative laboratory programs. This paper describes the methods used by the faculty to integrate innovative design experiences into the undergraduate programs at Western Washington University. The CIM projects in the Manufacturing Engineering Technology program are used to illustrate

Kathleen L. Kitto

1998-01-01

82

Impact Crater Experiments for Introductory Physics and Astronomy Laboratories  

ERIC Educational Resources Information Center

Activity-based collisional analysis is developed for introductory physics and astronomy laboratory experiments. Crushable floral foam is used to investigate the physics of projectiles undergoing completely inelastic collisions with a low-density solid forming impact craters. Simple drop experiments enable determination of the average acceleration,…

Claycomb, J. R.

2009-01-01

83

In Situ Techniques for Monitoring Electrochromism: An Advanced Laboratory Experiment  

ERIC Educational Resources Information Center

This experiment employs current technology to enhance and extend existing lab content. The basic principles of spectroscopic and electroanalytical techniques and their use in determining material properties are covered in some detail in many undergraduate chemistry programs. However, there are limited examples of laboratory experiments with in…

Saricayir, Hakan; Uce, Musa; Koca, Atif

2010-01-01

84

CONVECTIVE DIFFUSION FIELD MEASUREMENTS COMPARED WITH LABORATORY AND NUMERICAL EXPERIMENTS  

EPA Science Inventory

Some of the more fundamental diffusion parameters measured in the CONDORS convective diffusion field experiment are compared with laboratory experiment and numerical modeling results by means of nondimensionalizations using convective scaling (i.e., mixing depth, z sub i, for len...

85

Disposition of transuranic residues from plutonium isentropic compression experiment (Pu-ice) conducted at Z machine  

SciTech Connect

In 1992, the U.S. Congress passed legislation to discontinue above- and below-ground testing of nuclear weapons. Because of this, the U.S. Department of Energy (DOE) must rely on laboratory experiments and computer-based calculations to verify the reliability of the nation's nuclear stockpile. The Sandia National Laboratories/New Mexico (SNL/NM) Z machine was developed by the DOE to support its science-based approach to stockpile stewardship. SNL/NM researchers also use the Z machine to test radiation effects on various materials in experiments designed to mimic nuclear explosions. Numerous components, parts, and materials have been tested. These experiments use a variety of radionuclides; however, plutonium (Pu) isotopes with greater than ninety-eight percent enrichment are the primary radionuclides used in the experiments designed for stockpile stewardship. In May 2006, SNL/NM received authority that the Z Machine Isentropic Compression Experiments could commence. Los Alamos National Laboratory (LANL) provided the plutonium targets and loaded the target assemblies, which were fabricated by SNL/NM. LANL shipped the loaded assemblies to SNL/NM for Z machine experiments. Three experiments were conducted from May through July 2006. The residues from each experiment, which weighed up to 913 pounds, were metallic and packaged into a respective 55-gallon drum each. Based on a memorandum of understanding between the two laboratories, LANL provides the plutonium samples and the respective radio-isotopic information. SNL/NM conducts the experiments and provides temporary storage for the drums until shipment to LANL for final waste certification for disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. This paper presents a comprehensive approach for documenting generator knowledge for characterization of waste in cooperation with scientists at the two laboratories and addresses a variety of topics such as material control and accountability, safeguards of material, termination of safeguards for eventual shipment from SNL/NM to LANL, associated approvals from DOE-Carlsbad Field Office, which governs WIPP and various notifications. It portrays a comprehensive approach needed for successful completion of a complex project between two national laboratories.

Goyal, Kapil K [Los Alamos National Laboratory; French, David M [Los Alamos National Laboratory; Humphrey, Betty J [WESTON SOLUTIONS INC.; Gluth, Jeffry [SNL

2010-01-01

86

Redefining Authentic Research Experiences in Introductory Biology Laboratories and Barriers to Their Implementation  

PubMed Central

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are poorly defined. To guide future reform efforts in this area, we conducted a national survey of biology faculty members to determine 1) their definitions of authentic research experiences in laboratory classes, 2) the extent of authentic research experiences currently experienced in their laboratory classes, and 3) the barriers that prevent incorporation of authentic research experiences into these classes. Strikingly, the definitions of authentic research experiences differ among faculty members and tend to emphasize either the scientific process or the discovery of previously unknown data. The low level of authentic research experiences in introductory biology labs suggests that more development and support is needed to increase undergraduate exposure to research experiences. Faculty members did not cite several barriers commonly assumed to impair pedagogical reform; however, their responses suggest that expanded support for development of research experiences in laboratory classes could address the most common barrier. PMID:24591509

Spell, Rachelle M.; Guinan, Judith A.; Miller, Kristen R.; Beck, Christopher W.

2014-01-01

87

Redefining authentic research experiences in introductory biology laboratories and barriers to their implementation.  

PubMed

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are poorly defined. To guide future reform efforts in this area, we conducted a national survey of biology faculty members to determine 1) their definitions of authentic research experiences in laboratory classes, 2) the extent of authentic research experiences currently experienced in their laboratory classes, and 3) the barriers that prevent incorporation of authentic research experiences into these classes. Strikingly, the definitions of authentic research experiences differ among faculty members and tend to emphasize either the scientific process or the discovery of previously unknown data. The low level of authentic research experiences in introductory biology labs suggests that more development and support is needed to increase undergraduate exposure to research experiences. Faculty members did not cite several barriers commonly assumed to impair pedagogical reform; however, their responses suggest that expanded support for development of research experiences in laboratory classes could address the most common barrier. PMID:24591509

Spell, Rachelle M; Guinan, Judith A; Miller, Kristen R; Beck, Christopher W

2014-01-01

88

Laboratory Experiment of Saltwater Intrusion into Freshwater Aquifer  

NASA Astrophysics Data System (ADS)

It is important for safety assessment of high-level radioactive waste geologic disposal to understand groundwater flow in deep underground accurately. Especially groundwater flow in the coastal area considered to be quite complex that involves density and hydraulic gradient driven flow of freshwater and saltwater. Furthermore, bentonite, which is one of the favored artificial barrier materials, may not swell very well in saltwater as it does in freshwater, and therefore may not provide a reliable seal if salinity is high enough. In order to understand the behavior of saltwater intrusion into freshwater in deep underground, we constructed a laboratory equipment "Mini-MACRO" named after the original large scale MACRO (MAss transport Characterization in host ROck) and aimed to increase a precision and efficiency of experiment. Mini-MACRO equipment consists of three parts: a sandbox (0.5m x 0.25m x 0.1m) and each reservoir tank for saltwater and freshwater. Saltwater intrusion experiments are conducted using glass beads (sub-millimeter in diameter) and colored saltwater in the sandbox with a transparent face plate to allow visual observation. In the present paper we summarize the concept of the equipment design and the results of the experiment that we created several cases of experimental conditions to observe the saltwater intrusion behavior against various hydraulic gradients and densities of saltwater. This equipment contributes to the better understanding of saltwater intrusion behavior and to increasing confidence in modeling methodology of groundwater flow and mass transport in deep underground through comparison with numerical analysis. We believe that it is crucial for the safety assessment of geologic disposal to integrate this knowledge.

Maekawa, K.; Karasaki, K.; Takasu, T.

2006-12-01

89

The student perspective of high school laboratory experiences  

NASA Astrophysics Data System (ADS)

High school science laboratory experiences are an accepted teaching practice across the nation despite a lack of research evidence to support them. The purpose of this study was to examine the perspective of students---stakeholders often ignored---on these experiences. Insight into the students' perspective was explored progressively using a grounded theory methodology. Field observations of science classrooms led to an open-ended survey of high school science students, garnering 665 responses. Twelve student interviews then focused on the data and questions evolving from the survey. The student perspective on laboratory experiences revealed varied information based on individual experience. Concurrent analysis of the data revealed that although most students like (348/665) or sometimes like (270/665) these experiences, some consistent factors yielded negative experiences and prompted suggestions for improvement. The category of responses that emerged as the core idea focused on student understanding of the experience. Students desire to understand the why do, the how to, and the what it means of laboratory experiences. Lacking any one of these, the experience loses educational value for them. This single recurring theme crossed the boundaries of age, level in school, gender, and even the student view of lab experiences as positive or negative. This study suggests reflection on the current laboratory activities in which science teachers engage their students. Is the activity appropriate (as opposed to being merely a favorite), does it encourage learning, does it fit, does it operate at the appropriate level of inquiry, and finally what can science teachers do to integrate these activities into the classroom curriculum more effectively? Simply stated, what can teachers do so that students understand what to do, what's the point, and how that point fits into what they are learning outside the laboratory?

Lambert, R. Mitch

90

Spacecraft Dynamics as Related to Laboratory Experiments in Space. [conference  

NASA Technical Reports Server (NTRS)

Proceedings are presented of a conference sponsored by the Physics and Chemistry Experiments in Space Working Group to discuss the scientific and engineering aspects involved in the design and performance of reduced to zero gravity experiments affected by spacecraft environments and dynamics. The dynamics of drops, geophysical fluids, and superfluid helium are considered as well as two phase flow, combustion, and heat transfer. Interactions between spacecraft motions and the atmospheric cloud physics laboratory experiments are also examined.

Fichtl, G. H. (editor); Antar, B. N. (editor); Collins, F. G. (editor)

1981-01-01

91

CSI flight experiment projects of the Naval Research Laboratory  

NASA Technical Reports Server (NTRS)

The Naval Research Laboratory (NRL) is involved in an active program of CSI flight experiments. The first CSI flight experiment of the Naval Research Laboratory, the Low Power Atmospheric Compensation Experiment (LACE) dynamics experiment, has successfully measured vibrations of an orbiting satellite with a ground-based laser radar. The observations, made on January 7, 8 and 10, 1991, represent the first ever measurements of this type. In the tests, a narrowband heterodyne CO2 laser radar, operating at a wavelength of 10.6 microns, detected vibration induced differential-Doppler signatures of the LACE satellite. Power spectral densities of forced oscillations and modal frequencies and damping rates of free-damped vibrations were obtained and compared with finite element structural models of the LACE system. Another manifested flight experiment is the Advanced Controls Technology Experiment (ACTEX) designed to demonstrate active and passive damping with piezo-electric (PZT) sensors and actuators. This experiment was developed under the management of the Air Force Phillips Laboratory with integration of the experiment at NRL. It is to ride as a secondary, or 'piggyback,' experiment on a future Navy satellite.

Fisher, Shalom

1993-01-01

92

Non-Radioactive DNA Hybridization Experiments for the Undergraduate Laboratory: The Southern Blot Analysis  

NSDL National Science Digital Library

This resource provides detailed instructions to conduct laboratory exercises leading to the detection of homologous DNA sequences via Southern blot analysis. Unlike standard protocols for Southern blotting, these experiments do not require students to handle radioactive materials, and is therefore a safer and less expensive alternative to standard methodologies.

Susan J. Karcher (Purdue University;)

1992-01-01

93

Developing School Laboratories To Promote the Establishment of Individual Experience Programs. Final Report.  

ERIC Educational Resources Information Center

A project was conducted to promote and develop individual Supervised Agricultural Experience (SAE) programs in Arkansas through the development of laboratories. It was felt that strong SAE programs enhance the instructional portion of agriculture education, serve as a motivational tool, and improve the relations between the local school and…

Valley Springs School District 2, AR.

94

Laboratory Experiments for Seawater Intrusion into Freshwater Aquifer with Heterogeneity  

NASA Astrophysics Data System (ADS)

It is important for safety assessment of high-level radioactive waste geologic disposal to understand groundwater flow in deep underground accurately. Especially, groundwater flow in the coastal area is considered to be quite complex that involves density and hydraulic gradient driven flow of freshwater and seawater. In order to understand the behavior of seawater intrusion into freshwater in deep underground, we constructed a laboratory equipment, 'Mini-MACRO' (MAss transport Characterization in host ROck). Mini-MACRO consists of three parts: a sandbox (0.5m x 0.25m x 0.1m) and a reservoir tank on each side containing saltwater simulating seawater and freshwater, respectively. Seawater intrusion experiments are conducted using glass beads (sub- millimeter in diameter) and colored saltwater in the sandbox with a transparent face plate to allow visual observation. We created several cases of experimental conditions to observe the seawater intrusion behavior into two-layered stratum against various hydraulic gradients and densities of saltwater resembling the so-called Henry Problem. We confirmed that the results using this equipment match numerical results under simple heterogeneous condition. These results contribute to the better understanding of seawater intrusion behavior and to increasing confidence in modeling methodology of groundwater flow and mass transport in deep underground through comparison with numerical analysis. We believe that it is crucial for the safety assessment of geologic disposal to integrate this knowledge.

Maekawa, K.; Karasaki, K.; Takasu, T.

2007-12-01

95

On integrating LES and laboratory turbulent flow experiments  

SciTech Connect

Critical issues involved in large eddy simulation (LES) experiments relate to the treatment of unresolved subgrid scale flow features and required initial and boundary condition supergrid scale modelling. The inherently intrusive nature of both LES and laboratory experiments is noted in this context. Flow characterization issues becomes very challenging ones in validation and computational laboratory studies, where potential sources of discrepancies between predictions and measurements need to be clearly evaluated and controlled. A special focus of the discussion is devoted to turbulent initial condition issues.

Grinstein, Fernando Franklin [Los Alamos National Laboratory

2008-01-01

96

Lava-substrate heat transfer: Laboratory experiments and thermodynamic modeling  

NASA Astrophysics Data System (ADS)

We have performed laboratory experiments and numerical modeling to investigate the heat transfer from a lava flow into various substrate materials, focusing on the effects of the differing thermophysical properties of substrate materials. Initial motivation for this project developed from the desire to understand the loss of solar wind volatiles embedded in lunar regolith deposits that were subsequently covered by a lava flow. The Moon lacks a significant atmosphere and magnetosphere, leaving the surface regolith exposed to bombardment by solar flare and solar wind particles, and by the cosmogenic products of galactic cosmic rays. Preservation of particle-rich regolith deposits may have occurred by the emplacement of an active lava flow on top of the regolith layer, provided the embedded particles survive heating by the lava. During future expeditions to the lunar surface, ancient regolith deposits could be sampled through surface drilling to extract the extra-lunar particles, revealing a history of the solar activity and galactic events not available on the Earth. This project also has important implications for terrestrial lava flows, particularly in the prediction of lava flow hazards. Lava erupted on Earth may be emplaced on various substrates, including solid lava rock, volcanic tephra, sands, soils, etc. The composition, grain size, consolidation, moisture content, etc. of these materials will vary greatly and have different effects on the cooling of the flow. Accounting for specific properties of the substrate could be an important improvement in lava flow models We have performed laboratory experiments in collaboration with the Department of Art and Art History at the University of Hawaii at Manoa in which ~5-6 kg of basalt, collected at Kilauea Volcano, Hawaii, is melted to ~1200 °C. The lava is poured into a device constructed of calcium silicate sheeting that has been filled with a solid or particulate substrate material and embedded with thermocouples. Internal temperatures are monitored by the thermocouple array, while external temperatures are monitored by a Forward Looking Infrared Radiometer (FLIR) video camera. The experimental data thus describe the cooling rates of the system, and reveal the release of latent heat of crystallization within the cooling lava. These experiments have been conducted in conjunction with numerical simulations of the heat transfer from a lava flow into various substrates, to quantify the depth reached by the heat pulse as it penetrates the substrate. Models include material-specific, temperature-dependent thermophysical properties, including thermal conductivity, specific heat capacity, and latent heat of crystallization. We find that particulate materials, such as lunar regolith, sand, and soils will be heated to depths shallower than solid materials. In addition, the particulate materials will act as insulators, shielding the lava flow from basal cooling and maintaining high temperatures in the flow core. These results suggest that lava flows emplaced on a dry particulate terrain will remain above solidus for a longer duration, allowing the lava to flow further than when emplaced on a solid substrate.

Rumpf, M.; Fagents, S. A.; Hamilton, C. W.; Wright, R.; Crawford, I.

2012-12-01

97

Cleanup of a Department of Energy Nonreactor Nuclear Facility: Experience at the Los Alamos National Laboratory High Pressure Tritium Laboratory  

SciTech Connect

On October 25, 1990, Los Alamos National Laboratory (LANL) ceased programmatic operations at the High Pressure Tritium Laboratory (HPTL). Since that time, LANL has been preparing the facility for transfer into the Department of Energy`s (DOE`s) Decontamination and Decommissioning Program. LANL staff now has considerable operational experience with the cleanup of a 40-year-old facility used exclusively to conduct experiments in the use of tritium, the radioactive isotope of hydrogen. Tritium and its compounds have permeated the HPTL structure and equipment, have affected operations and procedures, and now dominate efforts at cleanup and disposal. At the time of shutdown, the HPTL still had a tritium inventory of over 100 grams in a variety of forms and containers.

Horak, H.L.

1995-02-01

98

Experiments at The Virtual National Laboratory for Heavy Ion Fusion  

Microsoft Academic Search

An overview of experiments is presented, in which the physical dimensions, emittance and perveance are scaled to explore driver-relevant beam dynamics. Among these are beam merging, focusing to a small spot, and bending and recirculating beams. The Virtual National Laboratory for Heavy Ion Fusion (VNL) is also developing two driver-scale beam experiments involving heavy-ion beams with I(sub beam) about 1

P. A. Seidl; F. M. Bieniosek; C. M. Celata; A. Faltens; J. W. Kwan; S. A. MacLaren; D. Ponce; D. Shuman; S. Yu; L. Ahle; S. Lund; A. Molvik; T. C. Sangster

2000-01-01

99

Effective Laboratory Experiences for Students with Disabilities: The Role of a Student Laboratory Assistant  

NASA Astrophysics Data System (ADS)

Two separate experiences with students whose disabilities significantly limited the number of laboratory activities they could accomplish independently has given us a general experience base for determining successful strategies for accommodating students facing these situatiuons. For a student who had substantially limited physical mobility and for a student who had no visual ability, employing a student laboratory assistant allowed the students with disabilities to have a productive and positive laboratory experience. One of the priorities in these situations should be to avoid depersonalizing the student with a disability. Interactions with the instructor and with other students should focus on the disabled student rather than the student laboratory assistant who may be carrying out specific tasks. One of the most crucial aspects of a successful project is the selection of a laboratory assistant who has excellent interpersonal skills and who will add his or her creativity to that of the student with a disability to meet unforeseen challenges. Other considerations are discussed, such as the importance of advance notification that a disabled student has enrolled in a course as well as factors that should contribute to choosing an optimum laboratory station for each situation.

Pence, Laura E.; Workman, Harry J.; Riecke, Pauline

2003-03-01

100

Enhancing the Laboratory Experience Using Peer Evaluation of Group Laboratory Reports in a Fluid Mechanics Course  

NSDL National Science Digital Library

Peer evaluation of laboratory reports has been found to be a valuable tool in a junior level fluid mechanics laboratory. Readily available equipment makes it possible to have separate experiments investigating applications of the mechanical energy equation to nearly ideal venturis, an array of flow meters, an array of various fittings, and a single pipe. Having each group of students carry out all four experiments and report on the results can lead to equipment utilization conflicts, student exhaustion, and a lack of attention to detail in the final laboratory reports. In spring of 2006 the author decided to streamline this segment of the laboratory by having each laboratory group (typically teams of four students) perform and report on only two of the four experiments listed above. They were, however, required to provide peer evaluation of the reports of another student group for the experiments which they did not personally carry out. These peer evaluations were then compared with the instructors evaluations of the same reports and feedback was given to both the group being evaluated and the evaluators. The expected benefits of this change were reduced stress on the students, increased student understanding of and appreciation for the laboratory report evaluation criteria, broader understanding of frictional losses in pipes and devices, and better utilization of the available laboratory equipment. Results from both spring 2006 and 2007 confirmed that the students did an excellent job of assessing the reports submitted by other groups, and exam performance confirmed their understanding of the processes involved in experiments which they evaluated but did not carry out. However, student performance on future laboratory reports did not improve significantly, as had been anticipated. In other words, although students could clearly identify the strengths and the weaknesses of laboratory reports written by others, this did not translate directly into an improvement in their own reports. Future efforts will focus on using this experience not only to reduce student work load and enhance learning, but also on using the experience to help students improve their own reporting skills.

Shaw, David

2012-05-29

101

Raising Environmental Awareness through Applied Biochemistry Laboratory Experiments  

ERIC Educational Resources Information Center

Our environment is under constant pressure and threat from various sources of pollution. Science students, in particular chemistry students, must not only be made aware of these issues, but also be taught that chemistry (and science) can provide solutions to such real-life issues. To this end, a newly developed biochemistry laboratory experiment

Salman Ashraf, S.

2013-01-01

102

An Enzyme Kinetics Experiment for the Undergraduate Organic Chemistry Laboratory  

ERIC Educational Resources Information Center

An experiment using [superscript 1]H NMR spectroscopy to observe the kinetics of the acylase 1-catalyzed hydrolysis of "N"-acetyl-DL-methionine has been developed for the organic laboratory. The L-enantiomer of the reactant is hydrolyzed completely in less than 2 h, and [superscript 1]H NMR spectroscopic data from a single sample can be worked up…

Olsen, Robert J.; Olsen, Julie A.; Giles, Greta A.

2010-01-01

103

Forensics as a Laboratory Experience in Small Group Communication.  

ERIC Educational Resources Information Center

Forensics programs can be laboratories for small group processes, whether or not they are explicitly recognized by either the participants or their teachers. Small group dynamics, as identified by M. Shaw (1981), are present and clearly define the forensic activity as a small group experience. The combination of being a small group, spending…

Zeuschner, Raymond Bud

104

EDUCATIONAL EXPERIMENTS WITH AN ONLINE MICROELECTRONICS CHARACTERIZATION LABORATORY  

Microsoft Academic Search

We have developed and deployed an online microelectronics characterization laboratory that allows the characterization of transistors and other microelectronic devices in real time through the internet. The architecture of this system was devised to accomplish two goals: 1) the delivery of a rich educational experience in microelectronic device characterization to remote computers, and 2) the ability to scale to a

J. A. del Alamo; J. Hardison; G. Mishuris; L. Brooks; C. McLean; V. Chan; L. Hui

105

Laboratory Experiment in Semiconductor Surface-Field Effects  

ERIC Educational Resources Information Center

A laboratory instructional program involving metal-insulator-semiconductor (MIS) devices is described. In the first of a two-part experiment, students become familiar with the important parameters of a simple MIS device and learn measurement techniques; in the second part, device fabrication procedures are learned. (DT)

Goodman, F. R.; And Others

1974-01-01

106

Lidocaine Metabolism and Toxicity: A Laboratory Experiment for Dental Students.  

ERIC Educational Resources Information Center

A laboratory exercise for dental students is presented using a toxic dose of lidocaine in place of an anesthetic dose of pentobarbital. The use of lidocaine demonstrates its toxic and lethal actions and increases the relevance of the experience for dental students. (Author/MLW)

Kusek, J. C.

1980-01-01

107

Radiative transfer theory verified by controlled laboratory experiments  

E-print Network

Radiative transfer theory verified by controlled laboratory experiments Michael I. Mishchenko,1 particles from 2% to 10%. Our results indicate that the VRTE can be applied safely to random particulate the Maxwell equations [1,2] has finally made the RT theory (RTT) a legitimate branch of physical optics. Yet

108

Evaluation of noise barriers for soundscape perception through laboratory experiments  

E-print Network

noise pollution caused by traffic noise from cars and trains in urban space. However, installationEvaluation of noise barriers for soundscape perception through laboratory experiments J.Y. Honga noise barriers. Field measurements were performed: the SPLs in front and rear of the barriers were

Paris-Sud XI, Université de

109

Differentiating Biochemistry Course Laboratories Based on Student Experience  

ERIC Educational Resources Information Center

Content and emphases in undergraduate biochemistry courses can be readily tailored to accommodate the standards of the department in which they are housed, as well as the backgrounds of the students in the courses. A more challenging issue is how to construct laboratory experiences for a class with both chemistry majors, who usually have little or…

Jakubowski, Henry V.

2011-01-01

110

A Unit Cell Laboratory Experiment: Marbles, Magnets, and Stacking Arrangements  

ERIC Educational Resources Information Center

An undergraduate first-semester general chemistry laboratory experiment introducing face-centered, body-centered, and simple cubic unit cells is presented. Emphasis is placed on the stacking arrangement of solid spheres used to produce a particular unit cell. Marbles and spherical magnets are employed to prepare each stacking arrangement. Packing…

Collins, David C.

2011-01-01

111

LABORATORY EXPERIMENT 6 PRECIPITATION TITRATION WITH SILVER NITRATE.  

E-print Network

LABORATORY EXPERIMENT 6 PRECIPITATION TITRATION WITH SILVER NITRATE. The AgNO3 solution (~0.02 M in the titration of chloride ion with silver nitrate. The first excess of titrant results in the formation of a red Ag2CrO4. Calculations: From the volume of silver nitrate solution used fopr titration, calculate

Nazarenko, Alexander

112

LABORATORY EXPERIMENT 5 PRECIPITATION TITRATION WITH SILVER NITRATE.  

E-print Network

LABORATORY EXPERIMENT 5 PRECIPITATION TITRATION WITH SILVER NITRATE. The AgNO3 solution (~0.02 M in the titration of chloride ion with silver nitrate. The first excess of titrant results in the formation of a red Ag2CrO4. Calculations: From the volume of silver nitrate solution used fopr titration, calculate

Nazarenko, Alexander

113

Advanced Undergraduate Laboratory Experiment in Inelastic Electron Tunneling Spectroscopy.  

ERIC Educational Resources Information Center

An advanced undergraduate laboratory experiment in inelastic electron tunneling spectroscopy is described. Tunnel junctions were fabricated, the tunneling spectra of several molecules absorbed on the surface of aluminum oxide measured, and mode assignments made for several of the prominent peaks in spectra using results obtained from optical…

White, H. W.; Graves, R. J.

1982-01-01

114

Experiences and prospects of nuclear astrophysics in underground laboratories  

NASA Astrophysics Data System (ADS)

Impressive progress has been made in the course the last decades in understanding astrophysical objects. Increasing precision of nuclear physics data has contributed significantly to this success, but now a better understanding of several important findings is frequently limited by uncertainties related to the available nuclear physics data. Consequently it is desirable to improve significantly the quality of these data. An important step towards higher precision is an excellent signal to background ratio of the data. Placing an accelerator facility inside an underground laboratory reducing the cosmic ray induced background by six orders of magnitude is a powerful method to reach this goal, even though careful reduction of environmental and beam induced background must still be considered. Experience in the field of underground nuclear astrophysics has been gained since 20 years due to the pioneering work of the LUNA Collaboration (Laboratory for Underground Nuclear Astrophysics) operating inside the underground laboratories of the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. Based on the success of this work presently also several other projects for underground laboratories dedicated to nuclear astrophysics are being pursued worldwide. This contribution will give a survey of the past experience in underground nuclear astrophysics as well as an outlook on future developments.

Junker, M.

2014-05-01

115

ORGANOTIN TOXICITY STUDIES CONDUCTED WITH SELECTED MARINE ORGANISMS AT EPA'S ENVIRONMENTAL RESEARCH LABORATORY, GULF BREEZE, FLORIDA  

EPA Science Inventory

Studies on effect of bis(tri-n-butyltin)oxide (TBTO) and other organotins on marine species have been conducted at the U.S. Environmental Protection Agency's laboratory at Gulf Breeze, Florida, since 1983. First studies were done on two species of algae, Skeletonema costatum and ...

116

Internal solitons in laboratory experiments: Comparison with theoretical models  

NASA Astrophysics Data System (ADS)

Nonlinear internal solitary waves observed in laboratory experiments are discussed from the standpoint of their relation to different soliton theories, from the classical integrable models such as the Korteweg-de Vries, Gardner, Benjamin-Ono, and Joseph-Kubota-Ko-Dobbs equations and their modifications, through the nonintegrable models describing higher-order nonlinear effects, viscosity, rotation, and cylindrical spreading, to the strongly nonlinear models. First, these theoretical models are briefly described and, then, laboratory data and their comparison with the theory are presented.

Ostrovsky, L. A.; Stepanyants, Y. A.

2005-09-01

117

Analysis of Microgravity Experiments Conducted on the Apollo Spacecraft  

NASA Technical Reports Server (NTRS)

This Technical Memorandum (TM) discusses the microgravity experiments carried out during the later missions of the Apollo program. Microgravity experiments took place during the Apollo 14, 16, and 17 missions and consisted of four experiments in various materials processing concentrations with two of the four experiments taking place over the course of two missions. Experiments consist of composite casting, electrophoresis, heat flow and convection, and liquid transfer. This TM discusses the background, the workup, execution, and results of each experiment. In addition, the historical significance of each experiment to future applications/NASA programs is discussed.

Sharpe, R. J.; Wright, M. D.

2009-01-01

118

Intraspecific variation in Potamogeton pectinatus L.: a controlled laboratory experiment  

Microsoft Academic Search

\\u000a In a controlled laboratory experiment, the question was addressed whether intraspecific variation in Potamogeton pectinatus L. has a genotypic component. Two populations from contrasting habitats in The Netherlands were tested, one habitat was the\\u000a exposed and eutrophic freshwater Lake Veluwe and the other a brackish ditch on the island of Texel. Weight frequency distributions\\u000a of the natural tuber banks in

J. E. Vermaat; M. J. M. Hootsmans

1993-01-01

119

Does Competition Enhance Performance or Cheating? A Laboratory Experiment  

Microsoft Academic Search

In this paper we experimentally test whether competing for a desired reward does not only affect individuals? performance, but also their tendency to cheat. Recent doping scandals in sports as well as forgery and plagiarism scandals in academia have been partially explained by ?competitive pressures?, which suggests a link between competition and cheating. In our experiment subjects conduct a task

Christiane Schwieren; Doris Weichselbaumer

2008-01-01

120

Does competition enhance performance or cheating? A laboratory experiment  

Microsoft Academic Search

In this paper, we experimentally test whether competing for a desired reward does not only affect individuals’ performance, but also their tendency to cheat. Recent doping scandals in sports as well as forgery and plagiarism scandals in academia have been partially explained by “competitive pressures”, which suggests a link between competition and cheating.In our experiment subjects conduct a task where

Christiane Schwieren; Doris Weichselbaumer

2010-01-01

121

A laboratory method to determine the hydraulic conductivity of mountain forest soils using undisturbed soil samples  

NASA Astrophysics Data System (ADS)

Determination of infiltration properties of soils under laboratory conditions necessitates the collection of soil samples in a way that maintains their natural physical properties. Mountain forest soils, containing rock fragments, root systems and a significant amount of organic matter, make it extremely difficult to test their hydraulic conductivity using both laboratory and field methods. A widely used technique of sampling by driving a cylinder into the ground in this type of soils causes damage to their structure resulting from the displacement of root systems and rock fragments as well as reduction of soil porosity. Thus, subsequent results contain an error that is difficult to estimate. The aim of the present research was: (1) to develop a laboratory method for testing the hydraulic conductivity of mountain forest soils, and in particular a method of collection of undisturbed soil samples, (2) to determine the influence of the applied method of collecting samples on the thickening of their peripheral layer and on elimination of increased infiltration at the boundary between the soil medium and the cylinder, (3) to determine the extent of the impact of the irregular shape of a sample on its hydraulic conductivity and (4) to develop an empirical method for determining the actual values of hydraulic conductivity, taking into account the error associated with the flow of water through samples with different shapes. The method of soil sampling consists in gradual formation of a cylindrical soil monolith and filling the free space between the monolith and the tri-cylindrical container with low-pressure assembly foam. This method ensures preservation of the natural physical properties of the examined samples and elimination of errors during the measurement of the hydraulic conductivity, caused by increased infiltration at the boundary between the soil medium and the cylinder. It was shown that the mean error of hydraulic conductivity determination, related to the irregular shape of samples, amounts to 11.57%. The error may be eliminated by the application of conversion coefficients.

Ilek, Anna; Kucza, Jaros?aw

2014-11-01

122

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 4: Programmatics  

NASA Technical Reports Server (NTRS)

Details are provided for scheduling, cost estimates, and support research and technology requirements for a space shuttle supported manned research laboratory to conduct selected communication and navigation experiments. A summary of the candidate program and its time phasing is included, as well as photographs of the 1/20 scale model of the shuttle supported Early Comm/Nav Research Lab showing the baseline, in-bay arrangement and the out-of-bay configuration.

1972-01-01

123

Application of maximum entropy optimal projection design synthesis to the NASA Spacecraft Control Laboratory Experiment (SCOLE)  

NASA Technical Reports Server (NTRS)

The scope of this study covered steady-state, continuous-time vibration control under disturbances applied to the Space Shuttle and continuous-time models of actuators, sensors, and disturbances. Focus was on a clear illustration of the methodology, therefore sensor/actuator dynamics were initially ignored, and a finite element model of the NASA Spacecraft Control Laboratory Experiment (SCOLE) was conducted, including products of inertia and offset of reflector CM from the mast tip.

Hyland, Dave; Davis, Larry

1984-01-01

124

PUREX environmental radiological surveillance - preoperational and operational support program conducted by Pacific Northwest Laboratory  

SciTech Connect

This report describes the radiological environmental sampling program that is being conducted at the US Department of Energy's (DOE) Hanford Site in support of resumed operation of the PUREX fuel processing plant. The report also summarizes preoperational radiological environmental data collected to date. The activities described herein are part of the ongoing Hanford Environmental Surveillance Program, operated by the Pacific Northwest Laboratory (PNL) for the DOE.

Sula, M.J.; Price, K.R.

1983-10-01

125

Georgia Teachers in Academic Laboratories: Research Experiences in the Geosciences  

NASA Astrophysics Data System (ADS)

The Georgia Intern-Fellowships for Teachers (GIFT) is a collaborative effort designed to enhance mathematics and science experiences of Georgia teachers and their students through summer research internships for teachers. By offering business, industry, public science institute and research summer fellowships to teachers, GIFT provides educators with first-hand exposure to the skills and knowledge necessary for the preparation of our future workforce. Since 1991, GIFT has placed middle and high school mathematics, science and technology teachers in over 1000 positions throughout the state. In these fellowships, teachers are involved in cutting edge scientific and engineering research, data analysis, curriculum development and real-world inquiry and problem solving, and create Action Plans to assist them in translating the experience into changed classroom practice. Since 2004, an increasing number of high school students have worked with their teachers in research laboratories. The GIFT program places an average of 75 teachers per summer into internship positions. In the summer of 2005, 83 teachers worked in corporate and research environments throughout the state of Georgia and six of these positions involved authentic research in geoscience related departments at the Georgia Institute of Technology, including aerospace engineering and the earth and atmospheric sciences laboratories. This presentation will review the history and the structure of the program including the support system for teachers and mentors as well as the emphasis on inquiry based learning strategies. The focus of the presentation will be a comparison of two placement models of the teachers placed in geoscience research laboratories: middle school earth science teachers placed in a 6 week research experience and high school teachers placed in 7 week internships with teams of 3 high school students. The presentation will include interviews with faculty to determine the value of these experiences to the scientific community and interviews/classroom observations of teachers to determine the transfer of knowledge from the teacher to the students through the implementation of their Action Plans into their classroom.

Barrett, D.

2005-12-01

126

Demonstrations and laboratory experiments in a senior level acoustics course.  

PubMed

The Physics Department at the U.S. Naval Academy has a senior level four credit course (SP436) in acoustics (called "Acoustics") that features a well-equipped laboratory including an anechoic chamber. The course is populated by Physics Majors along with a few Engineering Majors at times. This presentation will show how Mathematica 9 is used in the laboratory portion of the course to enhance lecture topics and student computational assignments. It is "hands-on" which helps motivate and enhance learning. Students learn the fundamentals of Mathematica as part of the laboratory experience. Tasks after data collection, including analysis and write-up, are done with this software. Workstations include laptop personal computers, spectrum analyzers, oscilloscopes, laser Doppler vibrometers, and various accelerometers, mics, hydrophones, and ultrasonic transducers. A demonstration of standing waves in a cylindrical cavity will be presented as a representation of some of our featured lab experiments-including: Helmholtz resonators, linear and nonlinear vibration of a circular membrane, or circular elastic plate, flexural waves on a thin bar, Chladni plates, the hanging oscillating chain, spectral analysis (Fourier series, Fourier integral), sound speed vs. temperature and salinity, acoustic landmine detection, moving coil loud speaker, waves on strings, transmitting arrays, and wave guide studies. PMID:25235066

Korman, Murray S

2014-04-01

127

Climate chamber for environmentally controlled laboratory airflow experiments.  

PubMed

Climate chambers have been widely used in in vitro and in vivo studies which require controlled environmental temperature and humidity conditions. This article describes a new desktop climate chamber that was developed for application of respiratory airflows on cultured nasal epithelial cells (NEC) under controlled temperature and humidity conditions. Flow experiments were performed by connecting the climate chamber to an airflow generator via a flow chamber with cultured NEC. Experiments at two controlled climate conditions, 25 degrees C and 40% relative humidity (RH) and 37 degrees C and 80%RH, were conducted to study mucin secretion from the cultures inresponse to the flow. The new climate chamber is a relatively simple and inexpensive apparatus which can easily be connected to any flow system for climate controlled flow experiments. This chamber can be easily adjusted to various in vitro experiments, as well as to clinical studies with animals or human subjects which require controlled climate conditions. PMID:20639592

Even-Tzur, Nurit; Zaretsky, Uri; Grinberg, Orly; Davidovich, Tomer; Kloog, Yoel; Wolf, Michael; Elad, David

2010-01-01

128

Laboratory and numerical experiments on double diffusive convection in an enclosure  

NASA Astrophysics Data System (ADS)

Laboratory and numerical experiments were carried out to study a two-layer, salt stratified fluid exposed to lateral heating and cooling in an enclosure. The governing parameters are the thermal Rayleigh number and the Buoyancy ratio. Laboratory experiments were conducted in a 10x10x10 cm enclosure, two side walls of which served as heat exchangers and the other two were insulated. Flow was visualized using the Schlieren technique. The numerical experiments were carried out using the Fluent software package. Due to the lateral heating of the opposite sidewalls a circulating natural convective flow is induced within each layer. Under certain conditions, the flow adjacent to the interface separating the two layers can become unstable and rows of vortices moving along the interface, above and below it in opposite directions, appear. Experiments were conducted under different values of the governing parameters to study the stability of this flow. Generally, good agreement was found between the laboratory and the numerical results. The results show that the critical Rayleigh number increases with the Buoyancy ratio.

Tanny, J.; Yakubov, B.; Cohen, J.; Dviri, R.

2001-11-01

129

Laboratory experiments on internal wave interactions with a pycnocline  

NASA Astrophysics Data System (ADS)

Laboratory experiments have been performed to investigate the interaction of internal waves with a pycnocline. An oscillating cylinder generated internal wave beams, which were observed using the synthetic schlieren technique. Internal waves incident on the pycnocline layer excited higher-frequency modes. In the absence of shear, a discrete spectrum of harmonic modes was generated due to nonlinear effects. These harmonic modes might play a role in the formation of internal solitary waves which have been observed in ocean pycnoclines. With shear, a continuous spectrum of excited modes was found.

Wunsch, Scott; Brandt, Alan

2012-12-01

130

Experiments at The Virtual National Laboratory for Heavy Ion Fusion  

SciTech Connect

An overview of experiments is presented, in which the physical dimensions, emittance and perveance are scaled to explore driver-relevant beam dynamics. Among these are beam merging, focusing to a small spot, and bending and recirculating beams. The Virtual National Laboratory for Heavy Ion Fusion (VNL) is also developing two driver-scale beam experiments involving heavy-ion beams with I(sub beam) about 1 Ampere to provide guidance for the design of an Integrated Research Experiment (IRE) for driver system studies within the next 5 years. Multiple-beam sources and injectors are being designed and a one-beam module will be built and tested. Another experimental effort will be the transport of such a beam through about 100 magnetic quadrupoles. The experiment will determine transport limits at high aperture fill factors, beam halo formation, and the influence on beam properties of secondary electron Research into driver technology will be briefly presented, including the development of ferromagnetic core materials, induction core pulsers, multiple-beam quadrupole arrays and plasma channel formation experiments for pinched transport in reactor chambers.

Seidl, P.A.; Bieniosek, F.M.; Celata, C.M.; Faltens, A.; Kwan, J.W.; MacLaren, S.A.; Ponce, D.; Shuman, D.; Yu, S.; Ahle, L.; Lund, S.; Molvik, A.; Sangster, T.C.

2000-07-24

131

Large scale laboratory experiments for water oxygenation under breaking waves  

NASA Astrophysics Data System (ADS)

Oxygenation experiments under breaking waves in large-scale experimental facilities are presented. Experiments were performed with a sloping beach at the wind wave flume of Delft Hydraulics and a three-layer rubble mound breakwater at the Schneideberg Wave Flume of Franzius Institut in Universitat Hannover. The scaling law of the phenomenon has not yet been determined and the model for prediction of the transfer coefficient from the wave characteristics needs to be refined by inclusion of a parameter describing the breaking. The apparent transfer coefficients for the large scale experiments were lower than those determined from small scale experiments in the Laboratory of Harbour Works, NTUA. However, the actual oxygen transfer coefficients, as computed using a discretized form of the transport equation and accounting for dispersion, are in the same order of magnitude for small and large scale experiments. Correlations of the oxygen transfer coefficients with dimensionless breaking wave indexing parameters are presented and a modified vorticity based renewal model incorporating the breaking wave Reynolds number is proposed, that describes both small and large scale experimental data well.

Tsoukala, V. K.; Daniil, E. I.; Moutzouris, C. I.

132

Teaching Experiences With a Virtual Network Laboratory* Ken Wong, Tilman Wolf  

E-print Network

deliver a high quality laboratory experience in advanced networking [3,7]. Our experience with ONLTeaching Experiences With a Virtual Network Laboratory* Ken Wong, Tilman Wolf , Sergey Gorinsky by university faculty, the quality of laboratory experiences is highly variable. Several factors contribute

Turner, Jonathan S.

133

SCAMP: A Tool for Conducting Interactive Information Retrieval Experiments  

E-print Network

and report on how participants perform under di cult querying conditions. Categories and Subject Descriptors, (ii) more ex- pensive to conduct, (ii) require more time to undertake, and (iv) are more di cult replication and reproduction, whereas in a live in- teractive environment it is di cult to reproduce

Azzopardi, Leif

134

Laboratory plasma physics experiments using merging supersonic plasma jets  

E-print Network

We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven rail guns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: $n_e\\approx n_i \\sim 10^{16}$ cm$^{-3}$, $T_e \\approx T_i \\approx 1.4$ eV, $V_{\\rm jet}\\approx 30$-100 km/s, mean charge $\\bar{Z}\\approx 1$, sonic Mach number $M_s\\equiv V_{\\rm jet}/C_s>10$, jet diameter $=5$ cm, and jet length $\\approx 20$ cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.

Hsu, S C; Merritt, E C; Adams, C S; Dunn, J P; Brockington, S; Case, A; Gilmore, M; Lynn, A G; Messer, S J; Witherspoon, F D

2014-01-01

135

Impact of flow velocity on biochemical processes - a laboratory experiment  

NASA Astrophysics Data System (ADS)

Understanding and predicting hydraulic and chemical properties of natural environments are current crucial challenges. It requires considering hydraulic, chemical and biological processes and evaluating how hydrodynamic properties impact on biochemical reactions. In this context, an original laboratory experiment to study the impact of flow velocity on biochemical reactions along a one-dimensional flow streamline has been developed. Based on the example of nitrate reduction, nitrate-rich water passes through plastic tubes at several flow velocities (from 6.2 to 35 mm min-1), while nitrate concentration at the tube outlet is monitored for more than 500 h. This experimental setup allows assessing the biologically controlled reaction between a mobile electron acceptor (nitrate) and an electron donor (carbon) coming from an immobile phase (tube) that produces carbon during its degradation by microorganisms. It results in observing a dynamic of the nitrate transformation associated with biofilm development which is flow-velocity dependent. It is proposed that the main behaviors of the reaction rates are related to phases of biofilm development through a simple analytical model including assimilation. Experiment results and their interpretation demonstrate a significant impact of flow velocity on reaction performance and stability and highlight the relevance of dynamic experiments over static experiments for understanding biogeochemical processes.

Boisson, A.; Roubinet, D.; Aquilina, L.; Bour, O.; Davy, P.

2014-08-01

136

Astronaut Mike Fincke Conducts Fluid Merging Viscosity Measurement (FMVM) Experiment  

NASA Technical Reports Server (NTRS)

Astronaut Mike Fincke places droplets of honey onto the strings for the Fluid Merging Viscosity Measurement (FMVM) investigation onboard the International Space Station (ISS). The FMVM experiment measures the time it takes for two individual highly viscous fluid droplets to coalesce or merge into one droplet. Different fluids and droplet size combinations were tested in the series of experiments. By using the microgravity environment, researchers can measure the viscosity or 'thickness' of fluids without the influence of containers and gravity using this new technique. Understanding viscosity could help scientists understand industrially important materials such as paints, emulsions, polymer melts and even foams used to produce pharmaceutical, food, and cosmetic products.

2004-01-01

137

Status of the Nuclear-Induced Conductivity Experiment (NICE) Project  

NASA Technical Reports Server (NTRS)

Nuclear-based magnetohydrodynamic (MHD) energy conversion has been pursued in various forms since the 1950's. The majority of this work was motivated by the compatibility of MHD generators with the high temperature achievable with a nuclear reactor and the associated potential for very high cycle efficiency. As a result of this perspective, methods for enhancing the electrical conductivity of the MHD flow have primarily focused on traditional thermal ionization processes, especially those utilizing alkali metal seeds. However, electrical conductivity enhancement via thermal interactions imposes significant limitations on the flow expansion through the generator, and hence on the ultimate power density. Furthermore, the introduction of an alkali metal seed into the flow significantly complicates the engineering design and increases the potential for system failures due to plating of the evaporated metal on cold surfaces.

Bitteker, Leo; Bragg-Sitton, Shannon M.; Litchford, Ron J.; Rodgers, Stephen L. (Technical Monitor)

2001-01-01

138

Guidelines and considerations for conducting experiments using tissue microarrays.  

PubMed

Tissue microarrays (TMAs) represent a powerful method for undertaking large-scale tissue-based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA-based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA-based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA-based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1-day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA-based research, including the pre-analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines. PMID:23672312

Ilyas, Mohammad; Grabsch, Heike; Ellis, Ian O; Womack, Chris; Brown, Robert; Berney, Dan; Fennell, Dean; Salto-Tellez, Manuel; Jenkins, Martin; Landberg, Goran; Byers, Richard; Treanor, Darren; Harrison, David; Green, Andrew R; Ball, Graham; Hamilton, Peter

2013-05-01

139

Heterogeneous ice nucleation parameterizations based on laboratory experiments  

NASA Astrophysics Data System (ADS)

Aerosol influences on mixed-phase and cold clouds have received increasing attention in recent years. Possible effects of anthropogenic aerosols include enhanced glaciation of mixed-phase clouds, deactivation of natural ice nuclei, or they could be negligible compared to the natural background. The numerical simulation and quantification of these effects requires aerosol-specific ice nucleation parameterizations, which can be based either on field measurements or on laboratory experiments. The advantage of laboratory studies is that the aerosol samples can be well characterized with respect to their composition and size distribution. A simple empirical parameterization of ice nucleation ability is the so-called active site density. Experiments in the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) chamber have been used as a basis for fitted active site densities for various particles, such as desert dusts, volcanic ash, agricultural soils and pollen grains. The parameterizations will be compared to results from other experiments, and the differences and limitations will be discussed. The derived values of the active site density are sensitive to assumptions on the particle shape. In addition, the temperature range which can be covered is limited by the detection threshold of the employed instrument. For deposition nucleation, it is more difficult to obtain temperature- and supersaturation-dependent fits of the active site density. Furthermore, other recently developed ice nucleation parameterizations (Phillips et al, 2008; DeMott et al, 2010; Hoose et al, 2010), which are based on continuous flow diffusion chamber measurements and classical nucleation theory, respectively, are presented as "equivalent active site densities" to make them directly comparable to the AIDA measurements and active site density fits. These approaches differ both with respect to their absolute values, temperature- and time-dependence. The resultant differences in predicted atmospheric ice nuclei concentrations will be shown for a simulation with the COSMO-ART model.

Hoose, C.; Möhler, O.; Niemand, M.; Steinke, I.

2012-04-01

140

Scaled Laboratory Collisionless Shock Experiments in the Large Plasma Device  

NASA Astrophysics Data System (ADS)

Collisionless shocks in space plasmas have been investigated since the fifties and are typically studied via in-situ satellite observations, which are limited due to the large structure of collisionless shocks in space environments relative to the satellite observation platform. Scaled, repeatable experiments in the Large Plasma Device (LAPD) at UCLA provide a test bed for studying collisionless shocks in the laboratory, where questions of ion and electron heating and acceleration can be addressed and examined in detail. The experiments are performed by ablating a graphite or plastic target using the Raptor kilojoule-class laser facility at UCLA. The laser provides an on-target energy in the range of 100-500 J that drives a super-Alfvénic (MA > 1) debris plasma across a background magnetic field (200-800 G) into the ambient, magnetized LAPD plasma. Typical plasma parameters in the LAPD consist of a H+ or He+ ambient plasma with a core column (diameter > 20 cm ) density ni ~ 1013 cm-3 and electron temperature Te ~ 10 eV embedded in a larger plasma discharge (diameter ~ 80 cm) of density ni ~ 1012 cm-3 and Te ~ 5 eV. The ambient ion temperature is Ti ~ 1 eV. Experimental results from the latest collisionless shock campaign will be presented and compared with two dimensional hybrid simulations of the experiment. Fielded diagnostics include Thomson scattering, ion spectroscopy, magnetic flux probes, Langmuir probes, and microwave reflectometry.

Clark, S. E.; Schaeffer, D.; Everson, E.; Bondarenko, A.; Winske, D.; Constantin, C.; Niemann, C.

2013-12-01

141

Electric Conduction in Solids: a Pedagogical Approach Supported by Laboratory Measurements and Computer Modelling Environments  

NASA Astrophysics Data System (ADS)

In this paper we present a pedagogic approach aimed at modeling electric conduction in semiconductors, built by using NetLogo, a programmable modeling environment for building and exploring multi-agent systems. `Virtual experiments' are implemented to confront predictions of different microscopic models with real measurements of electric properties of matter, such as resistivity. The relations between these electric properties and other physical variables, like temperature, are, then, analyzed.

Bonura, A.; Capizzo, M. C.; Fazio, C.; Guastella, I.

2008-05-01

142

Obtaining Valid Laboratory Data in Clinical Trials Conducted in Resource Diverse Settings: Lessons Learned from a Microbicide Phase III Clinical Trial  

PubMed Central

Background Over the last decade several phase III microbicides trials have been conducted in developing countries. However, laboratories in resource constrained settings do not always have the experience, infrastructure, and the capacity to deliver laboratory data meeting the high standards of clinical trials. This paper describes the design and outcomes of a laboratory quality assurance program which was implemented during a phase III clinical trial evaluating the efficacy of the candidate microbicide Cellulose Sulfate 6% (CS) [1]. Methodology In order to assess the effectiveness of CS for HIV and STI prevention, a phase III clinical trial was conducted in 5 sites: 3 in Africa and 2 in India. The trial sponsor identified an International Central Reference Laboratory (ICRL), responsible for the design and management of a quality assurance program, which would guarantee the reliability of laboratory data. The ICRL provided advice on the tests, assessed local laboratories, organized trainings, conducted supervision visits, performed re-tests, and prepared control panels. Local laboratories were provided with control panels for HIV rapid tests and Chlamydia trachomatis/Neisseria gonorrhoeae (CT/NG) amplification technique. Aliquots from respective control panels were tested by local laboratories and were compared with results obtained at the ICRL. Results Overall, good results were observed. However, discordances between the ICRL and site laboratories were identified for HIV and CT/NG results. One particular site experienced difficulties with HIV rapid testing shortly after study initiation. At all sites, DNA contamination was identified as a cause of invalid CT/NG results. Both problems were timely detected and solved. Through immediate feedback, guidance and repeated training of laboratory staff, additional inaccuracies were prevented. Conclusions Quality control guidelines when applied in field laboratories ensured the reliability and validity of final study data. It is essential that sponsors provide adequate resources for implementation of such comprehensive technical assessment and monitoring systems. Trial Registration ClinicalTrials.gov NCT00153777 and Current Controlled Trials ISRCTN95638385 PMID:21048963

Crucitti, Tania; Fransen, Katrien; Maharaj, Rashika; Tenywa, Tom; Massinga Loembe, Marguerite; Murugavel, Kailapuri Gangatharan; Mendonca, Kevin; Abdellati, Said; Beelaert, Greet; Van Damme, Lut

2010-01-01

143

Laboratory testing of heat pumps: Experience 1984 - 1986  

NASA Astrophysics Data System (ADS)

Experience is presented from laboratory testing of heat pumps at the Swedish National Testing Institute during the period 1984-1986. A total of 186 heat pumps have been so far tested at the institute, 71 of which were tested during the investigation period. Comparisons between results obtained during different years show that performance data improved significantly up to 1983, there after, improvements were marginal. Tested values for coefficients of performance and heating output are on average 10-12 percent below data given by manufacturers. Remarkably large deviations are shown to exist between different makes of heat pumps, concerning coefficient of performance, heating of sanitary hot water, defrosting efficiency, and noise levels. Additional results describing how various parameters, such as flow rate, temperature, humidity, etc. affect the operation of heat pumps are presented.

Fahlen, Per

144

Intelligent Experiment Design-Based Virtual Remote Sensing Laboratory  

NASA Astrophysics Data System (ADS)

We address unified intelligent descriptive experiment design regularization (DEDR) methodology for computer-aided investigation of new intelligent signal processing (SP) perspectives for collaborative remote sensing (RS) and distributed sensor network (SN) data acquisition, intelligent processing and information fusion. The sophisticated "Virtual RS Laboratory" (VRSL) software elaborated using the proposed DEDR methodology is presented. The VRLS provides the end-user with efficient computational tools to perform numerical simulations of different RS imaging problems. Computer simulation examples are reported to illustrate the usefulness of the elaborated VRSL for the algorithmic-level investigation of high-resolution image formation, enhancement, fusion and post-processing tasks performed with the artificial and real-world RS imagery.

Shkvarko, Yuriy; Santos, Stewart; Tuxpan, Jose

145

Air Force Phillips Laboratory autonomous space navigation experiment  

NASA Astrophysics Data System (ADS)

The Air Force Phillips Laboratory's Technology for Autonomous Operational Survivability (TAOS) space experiment is scheduled for launch in early 1993. The mission will test and evaluate two navigation systems that support autonomous satellite navigation. They are the Microcosm Autonomous Navigation System (MANS) and the six-channel GPS receiver. MANS is a true autonomous system that uses horizon scanners, modified for sun and moon detection, as primary measurement devices to determine position, velocity, and attitude and estimate position and velocity using a Kalman filter. The Rockwell GPS miniature receiver is a semiautonomous system which accesses the GPS network to determine spacecraft position and velocity. Position and velocity reference data will be generated using direct measurements from Air Force Satellite Control Network tracking stations, orbit reconstruction based on on-board beaconry, and postprocessed GPS data and solutions. Attitude reference will be provided by an on-board inertial measurement unit.

Anthony, Jack

1992-03-01

146

Slew maneuvers of Spacecraft Control Laboratory Experiment (SCOLE)  

NASA Technical Reports Server (NTRS)

This is the final report on the dynamics and control of slew maneuvers of the Spacecraft Control Laboratory Experiment (SCOLE) test facility. The report documents the basic dynamical equation derivations for an arbitrary large angle slew maneuver as well as the basic decentralized slew maneuver control algorithm. The set of dynamical equations incorporate rigid body slew maneuver and three dimensional vibrations of the complete assembly comprising the rigid shuttle, the flexible beam, and the reflector with an offset mass. The analysis also includes kinematic nonlinearities of the entire assembly during the maneuver and the dynamics of the interactions between the rigid shuttle and the flexible appendage. The equations are simplified and evaluated numerically to include the first ten flexible modes to yield a model for designing control systems to perform slew maneuvers. The control problem incorporates the nonlinear dynamical equations and is expressed in terms of a two point boundary value problem.

Kakad, Yogendra P.

1992-01-01

147

The Nature of Laboratory Learning Experiences in Secondary Science Online  

NASA Astrophysics Data System (ADS)

Teaching science to secondary students in an online environment is a growing international trend. Despite this trend, reports of empirical studies of this phenomenon are noticeably missing. With a survey concerning the nature of laboratory activities, this study describes the perspective of 35-secondary teachers from 15-different U.S. states who are teaching science online. The type and frequency of reported laboratory activities are consistent with the tradition of face-to-face instruction, using hands-on and simulated experiments. While provided examples were student-centered and required the collection of data, they failed to illustrate key components of the nature of science. The features of student-teacher interactions, student engagement, and nonverbal communications were found to be lacking and likely constitute barriers to the enactment of inquiry. These results serve as a call for research and development focused on using existing communication tools to better align with the activity of science such that the nature of science is more clearly addressed, the work of students becomes more collaborative and authentic, and the formative elements of a scientific inquiry are more accessible to all participants.

Crippen, Kent J.; Archambault, Leanna M.; Kern, Cindy L.

2013-06-01

148

LABORATORY EXPERIMENTS TO SIMULATE CO2 OCEAN DISPOSAL  

SciTech Connect

This Final Technical Report summarizes the technical accomplishments of an investigation entitled ''Laboratory Experiments to Simulate CO{sub 2} Ocean Disposal'', funded by the U.S. Department of Energy's University Coal Research Program. This investigation responds to the possibility that restrictions on greenhouse gas emissions may be imposed in the future to comply with the Framework Convention on Climate Change. The primary objective of the investigation was to obtain experimental data that can be applied to assess the technical feasibility and environmental impacts of oceanic containment strategies to limit release of carbon dioxide (CO{sub 2}) from coal and other fossil fuel combustion systems into the atmosphere. A number of critical technical uncertainties of ocean disposal of CO{sub 2} were addressed by performing laboratory experiments on liquid CO{sub 2} jet break-up into a dispersed droplet phase, and hydrate formation, under deep ocean conditions. Major accomplishments of this study included: (1) five jet instability regimes were identified that occur in sequence as liquid CO{sub 2} jet disintegration progresses from laminar instability to turbulent atomization; (2) linear regression to the data yielded relationships for the boundaries between the five instability regimes in dimensionless Ohnesorge Number, Oh, and jet Reynolds Number, Re, space; (3) droplet size spectra was measured over the full range of instabilities; (4) characteristic droplet diameters decrease steadily with increasing jet velocity (and increasing Weber Number), attaining an asymptotic value in instability regime 5 (full atomization); and (5) pre-breakup hydrate formation appears to affect the size distribution of the droplet phase primary by changing the effective geometry of the jet.

Stephen M. Masutani

1999-12-31

149

Conducting Closed Habitation Experiments: Experience from the Lunar Mars Life Support Test Project  

NASA Technical Reports Server (NTRS)

The Lunar-Mars Life Support Test Project (LMLSTP) was conducted from 1995 through 1997 at the National Aeronautics and Space Administration s (NASA) Johnson Space Center (JSC) to demonstrate increasingly longer duration operation of integrated, closed-loop life support systems that employed biological and physicochemical techniques for water recycling, waste processing, air revitalization, thermal control, and food production. An analog environment for long-duration human space travel, the conditions of isolation and confinement also enabled studies of human factors, medical sciences (both physiology and psychology) and crew training. Four tests were conducted, Phases I, II, IIa and III, with durations of 15, 30, 60 and 91 days, respectively. The first phase focused on biological air regeneration, using wheat to generate enough oxygen for one experimental subject. The systems demonstrated in the later phases were increasingly complex and interdependent, and provided life support for four crew members. The tests were conducted using two human-rated, atmospherically-closed test chambers, the Variable Pressure Growth Chamber (VPGC) and the Integrated Life Support Systems Test Facility (ILSSTF). Systems included test articles (the life support hardware under evaluation), human accommodations (living quarters, kitchen, exercise equipment, etc.) and facility systems (emergency matrix system, power, cooling, etc.). The test team was managed by a lead engineer and a test director, and included test article engineers responsible for specific systems, subsystems or test articles, test conductors, facility engineers, chamber operators and engineering technicians, medical and safety officers, and science experimenters. A crew selection committee, comprised of psychologists, engineers and managers involved in the test, evaluated male and female volunteers who applied to be test subjects. Selection was based on the skills mix anticipated for each particular test, and utilized information from psychological and medical testing, data on the knowledge, experience and skills of the applicants, and team building exercises. The design, development, buildup and operation of test hardware and documentation followed the established NASA processes and requirements for test buildup and operation.

Barta, Daniel J.; Edeen, Marybeth A.; Henninger, Donald L.

2006-01-01

150

Conducting Closed Habitation Experiments: Experience from the Lunar Mars Life Support Test Project  

NASA Technical Reports Server (NTRS)

The Lunar-Mars Life Support Test Project (LMLSTP) was conducted from 1995 through 1997 at the National Aeronautics and Space Administration s (NASA) Johnson Space Center (JSC) to demonstrate increasingly longer duration operation of integrated, closed-loop life support systems that employed biological and physicochemical techniques for water recycling, waste processing, air revitalization, thermal control, and food production. An analog environment for long-duration human space travel, the conditions of isolation and confinement also enabled studies of human factors, medical sciences (both physiology and psychology) and crew training. Four tests were conducted, Phases I, II, IIa and III, with durations of 15, 30,60 and 91 days, respectively. The first phase focused on biological air regeneration, using wheat to generate enough oxygen for one experimental subject. The systems demonstrated in the later phases were increasingly complex and interdependent, and provided life support for four crew members. The tests were conducted using two human-rated, atmospherically-closed test chambers, the Variable Pressure Growth Chamber (VPGC) and the Integrated Life Support Systems Test Facility (ILSSTF). Systems included test articles (the life support hardware under evaluation), human accommodations (living quarters, kitchen, exercise equipment, etc.) and facility systems (emergency matrix system, power, cooling, etc.). The test team was managed by a lead engineer and a test director, and included test article engineers responsible for specific systems, subsystems or test articles, test conductors, facility engineers, chamber operators and engineering technicians, medical and safety officers, and science experimenters. A crew selection committee, comprised of psychologists, engineers and managers involved in the test, evaluated male and female volunteers who applied to be test subjects. Selection was based on the skills mix anticipated for each particular test, and utilized information from psychological and medical testing, data on the knowledge, experience and skills of the applicants, and team building exercises. The design, development, buildup and operation of test hardware and documentation followed the established NASA processes and requirements for test buildup and operation.

Barta, Daniel J.; Edeen, Marybeth A.; Henninger, Donald L.

2004-01-01

151

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 3: Laboratory descriptions  

NASA Technical Reports Server (NTRS)

The following study objectives are covered: (1) identification of major laboratory equipment; (2) systems and operations analysis in support of the laboratory design; and (3) conceptual design of the comm/nav research laboratory.

1972-01-01

152

Laboratory experiments on the breakup of liquid metal diapirs  

NASA Astrophysics Data System (ADS)

The validity of the iron rain scenario, i.e. the widely accepted model for the dynamics of iron sedimentation through a magma ocean during the latest stage of the Earth's accretion, is explored via a suite of laboratory experiments. Liquid gallium and mixtures of water and glycerol are used as analogs of the iron and the molten silicate respectively. This allows us to investigate the effects of the viscosity ratio between iron and silicate and to reproduce the relevant effects of surface tension on the fragmentation dynamics. While the classical iron rain scenario considers a population of purely spherical drops with a single characteristic radius that fall towards the bottom of the magma ocean at a unique velocity without any further change, our experiments exhibit a variety of stable shapes for liquid metal drops, a large distribution of sizes and velocities, and an intense internal dynamics within the cloud with the superimposition of further fragmentations and merging events. Our results demonstrate that rich and complex dynamics occur in models of molten metal diapir physics. Further, we hypothesize that the inclusion of such flows into state of the art thermochemical equilibration models will generate a similarly broad array of complex, and likely novel, behaviors.

Wacheul, Jean-Baptiste; Le Bars, Michael; Monteux, Julien; Aurnou, Jonathan M.

2014-10-01

153

Turbulent thermal diffusion of aerosols in geophysics and laboratory experiments  

E-print Network

We discuss a new phenomenon of turbulent thermal diffusion associated with turbulent transport of aerosols in the atmosphere and in laboratory experiments. The essence of this phenomenon is the appearance of a nondiffusive mean flux of particles in the direction of the mean heat flux, which results in the formation of large-scale inhomogeneities in the spatial distribution of aerosols that accumulate in regions of minimum mean temperature of the surrounding fluid. This effect of turbulent thermal diffusion was detected experimentally. In experiments turbulence was generated by two oscillating grids in two directions of the imposed vertical mean temperature gradient. We used Particle Image Velocimetry to determine the turbulent velocity field, and an Image Processing Technique based on an analysis of the intensity of Mie scattering to determine the spatial distribution of aerosols. Analysis of the intensity of laser light Mie scattering by aerosols showed that aerosols accumulate in the vicinity of the minimum mean temperature due to the effect of turbulent thermal diffusion. Geophysical applications of the obtained results are discussed.

A. Eidelman; T. Elperin; N. Kleeorin; A. Krein; I. Rogachevskii; J. Buchholz; G. Gruenefeld

2004-11-11

154

Potential for Resource Competition between Eurasian Ruffe and Yellow Perch: Growth and RNA Responses in Laboratory Experiments  

Microsoft Academic Search

The ruffe Gymnocephalus cernuus, an exotic percid from Eurasia that is now established in limited areas of the Great Lakes, is invading areas currently occupied by native yellow perch Perca flavescens. We conducted two laboratory experiments to determine whether competition for benthic macroinvertebrate food (live aquatic oligochaetes) may occur, thereby resulting in reduced growth for one or both fish species.

Aimee H. Fullerton; Gary A. Lamberti; David M. Lodge; Frederick W. Goetz

2000-01-01

155

Laboratory evaluation of time domain reflectometry for continuous monitoring of stream stage, channel profile and aqueous conductivity.  

SciTech Connect

Time domain reflectometry (TDR) operates by propagating a radar frequency electromagnetic pulse down a transmission line while monitoring the reflected signal. As the electromagnetic pulse propagates along the transmission line, it is subject to impedance by the dielectric properties of the media along the transmission line (e.g., air, water, and sediment), reflection at dielectric discontinuities (e.g., air-water or water-sediment interface), and attenuation by electrically conductive materials (e.g., salts and clays). Taken together, these characteristics provide a basis for integrated stream monitoring, specifically, concurrent measurement of stream stage, channel profile, and aqueous conductivity. Requisite for such application is a means of extracting the desired stream parameters from measured TDR traces. Analysis is complicated by the fact that interface location and aqueous conductivity vary concurrently and multiple interfaces may be present at any time. For this reason a physically based multisection model employing the S11 scatter function and Debeye parameters for dielectric dispersion and loss is used to analyze acquired TDR traces. Here we explore the capability of this multisection modeling approach for interpreting TDR data acquired from complex environments, such as encountered in stream monitoring. A series of laboratory tank experiments was performed in which the depth of water, depth of sediment, and conductivity were varied systematically. Comparisons between modeled and independently measured data indicate that TDR measurements can be made with an accuracy of {+-} 3.4 x 10{sup -3} m for sensing the location of an air-water or water-sediment interface and {+-} 7.4% of actual for the aqueous conductivity.

Tidwell, Vincent Carroll; Brainard, James Robert

2005-03-01

156

Summary of scientific results. [experiments conducted on lunar surface during Apollo 17 flight  

NASA Technical Reports Server (NTRS)

The accomplishments of the Apollo 17 flight are summarized. The basic objective of the mission was to sample basin-rim highland material and adjacent mare material and to investigate the geological evolutionary relationship between these two major units. The lunar experiments which were conducted include: (1) lunar field geology, (2) surface electrical experiments, (3) lunar traverse gravimeter experiments, (4) lunar seismic profiling experiment, (5) lunar ejecta and meteorites experiment, (6) analysis of lunar atmosphere composition, and (7) heat flow experiments.

Parker, R. A.

1973-01-01

157

Practice-based Research Networks (PBRNs) Are Promising Laboratories for Conducting Dissemination and Implementation Research.  

PubMed

Dissemination and implementation science addresses the application of research findings in varied health care settings. Despite the potential benefit of dissemination and implementation work to primary care, ideal laboratories for this science have been elusive. Practice-based research networks (PBRNs) have a long history of conducting research in community clinical settings, demonstrating an approach that could be used to execute multiple research projects over time in broad and varied settings. PBRNs also are uniquely structured and increasingly involved in pragmatic trials, a research design central to dissemination and implementation science. We argue that PBRNs and dissemination and implementation scientists are ideally suited to work together and that the collaboration of these 2 groups will yield great value for the future of primary care and the delivery of evidence-based health care. PMID:25381072

Heintzman, John; Gold, Rachel; Krist, Alexander; Crosson, Jay; Likumahuwa, Sonja; DeVoe, Jennifer E

2014-01-01

158

Recording the PHILAE Touchdown using CASSE: Laboratory Experiments  

NASA Astrophysics Data System (ADS)

The landing of Philae on comet 67P/Churyumov-Gerasimenko is scheduled for November 14, 2014. Its landing feet house the triaxial acceleration sensors of CASSE (Comet Acoustic Surface Sounding Experiment [1]) which will thus be the first sensors to be in mechanical contact with the cometary surface. It is planned that CASSE will be in listening mode to record the deceleration of the lander by the collision with the comet. The analysis of this data will not only support an engineering analysis of the landing process itself but also yield information about the mechanical properties of the comet's surface. Here, we describe a series of controlled landings of a lander model. The tests were conducted in the Landing & Mobility Test Facility (LAMA) of the DLR Institute of Space Systems in Bremen, Germany, where an industrial robot can be programmed to move landers or rovers along predefined paths and under simulated low gravity (Figure 1).

Knapmeyer, M.; Faber, C.; Witte, L.; Schröder, S.; Tune, J.-B.; Möhlmann, D.; Arnold, W.; Roll, R.; Chares, B.; Fischer, H.-H.; Seidensticker, K. J.

2013-09-01

159

ISO 15189 accreditation: Requirements for quality and competence of medical laboratories, experience of a laboratory II  

Microsoft Academic Search

ObjectivesOur laboratory was accredited for 531 tests according to ISO 15189 standard (ISO 15189:2003 Medical laboratories - Particular requirements for quality and competence specifies the quality management system requirements particular to medical laboratories) in 2007. An ambitious and young group of laboratory personnel has spent efforts with commitment and dedication to complete the heavy work of preparation and passed through

Gulderen Yanikkaya-Demirel

2009-01-01

160

ISO 15189 Accreditation: Requirements for quality and competence of medical laboratories, experience of a laboratory I  

Microsoft Academic Search

AimMedical laboratories are the key partners in patient safety. Laboratory results influence 70% of medical diagnoses. Quality of laboratory service is the major factor which directly affects the quality of health care. The clinical laboratory as a whole has to provide the best patient care promoting excellence.

Omer Guzel; Ebru Ilhan Guner

2009-01-01

161

21 CFR 58.130 - Conduct of a nonclinical laboratory study.  

Code of Federal Regulations, 2013 CFR

...of a nonclinical laboratory study. (a) The nonclinical laboratory study shall be... (b) The test systems shall be monitored...of a nonclinical laboratory study, except those...data collection systems, shall...

2013-04-01

162

21 CFR 58.130 - Conduct of a nonclinical laboratory study.  

...of a nonclinical laboratory study. (a) The nonclinical laboratory study shall be... (b) The test systems shall be monitored...of a nonclinical laboratory study, except those...data collection systems, shall...

2014-04-01

163

Low-frequency wireless communications System-infrared laboratory experiments  

Microsoft Academic Search

A communications systems course laboratory component using an infrared (IR) communication system has been developed as part of the wireless education initiative at the Rose-Hulman Institute of Technology (RHIT), Terre Haute, IN. Students build the system up over several laboratory periods from distinct subsystems, each of which illustrates specific communications concepts. The multiweek laboratory project has the features of being

Wayne T. Padgett; Bruce A. Black; Bruce A. Ferguson

2006-01-01

164

Frictional sliding in layered rock: laboratory-scale experiments  

SciTech Connect

The work is part of the rock mechanics effort for the Yucca Mountain Site Characterization Program. The laboratory-scale experiments are intended to provide high quality data on the mechanical behavior of jointed structures that can be used to validate complex numerical models for rock-mass behavior. Frictional sliding between simulated rock joints was studied using phase shifting moire interferometry. A model, constructed from stacks of machined and sandblasted granite plates, contained a central hole bore normal to the place so that frictional slip would be induced between the plates near the hole under compressive loading. Results show a clear evolution of slip with increasing load. Since the rock was not cycled through loading- unloading, the quantitative differences between the three data sets are probably due to a ``wearing-in`` effect. The highly variable spatial frequency of the data is probably due to the large grain size of the granite and the stochastic frictional processes. An unusual feature of the evolution of slip with increasing load is that as the load gets larger, some plates seem to return to a null position. Figs, 6 refs.

Buescher, B.J.; Perry, K.E. Jr.; Epstein, J.S.

1996-09-01

165

Control of Spacecraft Control Laboratory Experiment (SCOLE) slew maneuvers  

NASA Technical Reports Server (NTRS)

This is the second report of a set of two reports on the dynamics and control of slewing maneuvers of NASA Spacecraft Control Laboratory Experiment (SCOLE). The control problem of slewing maneuvers of SCOLE is developed in terms of an arbitrary maneuver about any given axis. The control system is developed for the combined problem of rigid-body slew maneuver and vibration suppression of flexible appendage. The control problem is formulated by incorporating the nonlinear equations derived in the previous report and is expressed in terms of a two-point boundary value problem utilizing a quadratic type of performance index. The two-point boundary value problem is solved as a hierarchical control problem with the overall system being split in terms of two subsystems, namely the slewing of the entire assembly and the vibration suppression of the flexible antenna. The coupling variables between the two dynamical subsystems are identified and these two subsystems for control purposes are treated independently in parallel at the first level. Then the state-space trajectory of the combined problem is optimized at the second level.

Kakad, Y. P.

1987-01-01

166

Laboratory experiments of transitional and turbulent Ekman layers  

NASA Astrophysics Data System (ADS)

We present well controlled laboratory experiments of the Ekman boundary layer produced by spin-up or spin-down of the 13m diameter Coriolis rotating platform at Grenoble. Both homogeneous and stably stratified cases are considered. In the homogeneous case, each of the two branches of instabilities (type I and type II spirals) is captured in isolation by abruptly increasing the Reynolds number from 0 to a value ranging from 50 to 360. The corresponding wavelengths, orientation and growth rates are measured by Particle Image Velocimetry and compared with theory. The stable stratification tends to favour type II spirals. In the turbulent regime the friction law is found in good agreement with the theory of the Atmospheric Boundary Layer for a smooth wall, even in the transitional regime. By contrast the angle between wall stress and geostrophic wind is observed to switch abruptly from 45 degrees (laminar) to about 30 degrees (turbulent). The influence of vertical vorticity in the geostrophic flow is discussed.

Sommeria, Joel; Mathur, Manikandan; Sous, Damien

2013-04-01

167

Ferric sulfates on Mars: Surface Explorations and Laboratory Experiments  

NASA Astrophysics Data System (ADS)

Recent results from missions to Mars have reinforced the importance of sulfates for Mars science. They are the hosts of water, the sinks of acidity, and maybe the most active species in the past and current surface/near-surface processes on Mars. Fe-sulfate was found frequently by Spirit and Opportunity rovers: jarosite in Meridiani Planum outcrops and a less specific "ferric sulfate" in the salty soils excavated by Spirit at Gusev Crater. Pancam spectral analysis suggests a variety of ferric sulfates in these soils, i.e. ferricopiapite, jarosite, fibroferrite, and rhomboclase. A change in the Pancam spectral features occurred in Tyrone soils after ~ 190 sols of exposure to surface conditions. Dehydration of ferric sulfate is a possible cause. We synthesized eight ferric sulfates and conducted a series of hydration/dehydration experiments. Our goal was to establish the stability fields and phase transition pathways of these ferric sulfates. In our experiments, water activity, temperature, and starting structure are the variables. No redox state change was observed. Acidic, neutral, and basic salts were used. Ferric sulfate sample containers were placed into relative humidity buffer solutions that maintain static relative humidity levels at three temperatures. The five starting phases were ferricopiapite (Fe4.67(SO4)6(OH)2.20H2O), kornelite (Fe2(SO4)3.7H2O), rhomboclase (FeH(SO4)2.4H2O), pentahydrite (Fe2(SO4)3.5H2O), and an amorphous phase (Fe2(SO4)3.5H2O). A total of one hundred fifty experiments have been running for nearly ten months. Thousands of coupled Raman and gravimetric measurements were made at intermediate steps to monitor the phase transitions. The first order discovery from these experiments is the extremely large stability field of ferricopiapite. Ferricopiapite is the major ferric sulfate to precipitate from a Fe3+-S-rich aqueous solution at mid-low temperature, and it has the highest H2O/Fe ratio (~ 4.3). However, unlike the Mg-sulfate with highest hydration state (epsomite, at mid-low temperature), which would dehydrate readily at low relative humidity, ferricopiapite remains unchanged over ten months under extremely dry conditions. On the other hand, amorphous ferric sulfate which forms easily from solutions at dry conditions, is similar to the amorphous magnesium sulfate in stability field, thus can potentially be a very important phase in the phase transition pathways of ferric sulfates on Mars.

Wang, A.; Ling, Z.; Freeman, J. J.

2008-12-01

168

Theatre and Drama in Education: A Laboratory for Actual, Virtual or Vicarious Experience.  

ERIC Educational Resources Information Center

Explores the implications of envisioning theater and drama in education as a "laboratory for learning," citing that Theatre-In-Education fits the laboratory model by integrating formal theater as aesthetic experience with informal drama as a learning medium. (MM)

Combs, Charles

1988-01-01

169

Gas hydrate dissolution rates quantified with laboratory and seafloor experiments  

NASA Astrophysics Data System (ADS)

Methane hydrates are stable at high pressure, low temperature, and saturated methane concentrations. However, natural hydrates exist at the seafloor where methane concentrations are well below saturation. Under such conditions, hydrate outcrops should shrink rapidly as they dissolve into the surrounding seawater. However, some natural hydrate outcrops have been observed for years undergoing little to no visible signs of change. Further, hydrate dissolution rates vary greatly among sites where changes have been observed. In this study, we perforated a natural hydrate outcrop on the seafloor of the Gulf of Mexico and measured the expansion of the hole after 30 days. From the rate of volume loss, we calculated a dissolution rate of 15 cm y-1. This rate is nearly an order of magnitude slower than hydrate dissolution rates observed in the Northern Cascadia Margin. We hypothesized that crystal structure influences hydrate dissolution rates and that the variability observed in in situ hydrate dissolution is caused by different hydrate structures. To test this hypothesis, we measured methane hydrate (structure I) and propane hydrate (structure II) dissolution rates in a series of laboratory experiments. Hydrates were formed in a pressure vessel and maintained at pressure and temperature conditions conducive to hydrate stability. After formation, the gas source was removed. Dissolution rates were calculated by measuring the increase in the dissolved gas concentration over time. Structure I (methane) hydrate dissolved at an average rate of 5.2 ± 2.5 mM CH4 d-1. Structure II (propane) hydrate dissolved at an average rate of 0.3 ± 0.2 mM C3H8 d-1. The ratio of these dissolution rates was proportional to the ratio of methane and propane solubilities under the experimental conditions. This suggests that dissolution rates in our experiments were diffusion-controlled and not influenced by differences in the crystal structure. We propose that natural contaminants such as oils or biofilms may have slowed the dissolution rate of the hydrate we observed in the Gulf of Mexico.

Lapham, Laura L.; Wilson, Rachel M.; MacDonald, Ian R.; Chanton, Jeffrey P.

2014-01-01

170

This form must be completed by the PI or their designee. The form is designed to conduct a laboratory hazard assessment specific to activities in each laboratory. The laboratory hazard assessment  

E-print Network

1 This form must be completed by the PI or their designee. The form is designed to conduct work activities. The person conducting the assessment must verify that it is complete and that training has been conducted. This assessment consists of four sections: Section 1: Laboratory Information

Veiga, Pedro Manuel Barbosa

171

The 5th Annual NASA Spacecraft Control Laboratory Experiment (SCOLE) Workshop, part 2  

NASA Technical Reports Server (NTRS)

A collection of papers from the workshop are presented. The topics addressed include: the modeling, systems identification, and control synthesis for the Spacecraft Control Laboratory Experiment (SCOLE) configuration.

Taylor, Lawrence W., Jr. (compiler)

1990-01-01

172

The European Register for Specialists in Clinical Chemistry and Laboratory Medicine: Code of Conduct  

Microsoft Academic Search

The European Communities Confederation of Clinical Chemistry and Laboratory Medicine (EC4) opened a Register for European Specialists in Clinical Chemis- try and Laboratory Medicine in 1997. The operation of the Register is undertaken by a Register Committee (EC4RC). During the last 6 years more than 1500 spe- cialists in clinical chemistry and laboratory medicine have joined the Register. In this

Gerard Sanders; Matthias Opp; Janet McMurray; Ursula Koeller; Vic Blaton; Erik Lund; Aimo Harmoinen; Simone Zerah; Hannsjoerg Baum; Demetrios Rizos; Desmond Kenny; Mario Pazzagli; Hans Hoffman; Henrique Reguengo; Jose M. Queralto; Hans Wallinder; Rob Jansen; Michael Hallworth

2004-01-01

173

Laboratory Experiment for the Transient Response of a Stirred Vessel.  

ERIC Educational Resources Information Center

Provides background information, apparatus needed, and procedures for an experiment to measure transient response of a stirred vessel. The inexpensive apparatus can be used for two different experiments, reducing cost per experiment. Both experiments use salt dilution as the method of demonstration. (Author/JN)

Noble, R. D.; And Others

1983-01-01

174

Intern experience with the Environmental Laboratory of the U.S. Army Engineer Waterways Experiment Station: an internship report  

E-print Network

INTERN EXPERIENCE WITH THE ENVIRONMENTAL LABORATORY OF THE U.S. ARMY ENGINEER WATERWAYS EXPERIMENT STATION AN INTERNSHIP REPORT by Cl Ifford Lee Trultt Submitted to the College of Engineering of Texas A&M University in partial fulfillment.... Palermo Internship Supervisor Carl A. Erdman College of Engineering Representat i ve JL Herbert H. Richardson Dean of Eng i neer i ng MAY 1987 ABSTRACT Intern Experience with the Environmental Laboratory of the U.S. Army Engineer Waterways...

Truitt, Clifford Lee, 1948-

2013-03-13

175

Experiments on Vertical Mixing in Laboratory and the Yellow Sea  

NASA Astrophysics Data System (ADS)

Mixing induced by non-breaking surface waves was investigated in a wave tank by measuring the thermal destratification rate of the water column. One experiment without waves and four experiments with waves of amplitudes ranging from 1.0 to 1.5 cm and wavelength from 30 to 75 cm were conducted. Water temperature variations at depths from 4 to 12 cm below the surface were measured. In the layer from 4 to 7 cm, the originally dense isothermal lines disperse soon after the waves are generated, while the vertical gradient from 9 to 12 cm is maintained for a relatively long time. The time span, during which the water temperature becomes well-mixed, changes from about 20 hours for the case with no waves to tens of minutes for the case with waves, and it decreases with increasing wave amplitude and wavelength. Vertical distribution of turbulence kinetic energy (TKE) dissipation was measured at a station with water depth of 40m in the Yellow Sea from July 12 to July 14, 2010. Three casts of microstructure profiler MSS-60 were continuously launched from the sea surface down to the bottom at every hour. Among the three casts, two similar profiles of TKE dissipation were selected and averaged to denote the vertical distribution of TKE dissipation at the observation time. Finally, 51 profiles of TKE dissipation were obtained from 7:00 of July 12 to 9:00 of July 14. There is a layer of strong TKE dissipation just below the thermocline. The maximum value of dissipation rate in the layer can approach 1x10-6 m2/s3 while the background TKE dissipation is about 1x10-9 m2/s3. The strong dissipation layer exists during the whole observing period. The dissipation rate in the bottom layer changes with the tidal current. The dissipation rate becomes larger during stronger tidal current while the dissipation rate is close to the background value for the weak current velocity. The strong TKE dissipation below thermocline should be attributed to the shear induced by internal waves and the behavior of dissipation rate in the bottom layer corresponds to the velocity shear in the bottom boundary.

Dai, D.; Qiao, F.; Huang, C.; Guo, J.

2011-12-01

176

Water in cratonic lithosphere: Calibrating laboratory-determined models of electrical conductivity of mantle minerals using geophysical and petrological observations  

NASA Astrophysics Data System (ADS)

Measurements of electrical conductivity of "slightly damp" mantle minerals from different laboratories are inconsistent, requiring geophysicists to make choices between them when interpreting their electrical observations. These choices lead to dramatically different conclusions about the amount of water in the mantle, resulting in conflicting conclusions regarding rheological conditions; this impacts on our understanding of mantle convection, among other processes. To attempt to reconcile these differences, we test the laboratory-derived proton conduction models by choosing the simplest petrological scenario possible - cratonic lithosphere - from two locations in southern Africa where we have the most complete knowledge. We compare and contrast the models with field observations of electrical conductivity and of the amount of water in olivine and show that none of the models for proton conduction in olivine proposed by three laboratories are consistent with the field observations. We derive statistically model parameters of the general proton conduction equation that satisfy the observations. The pre-exponent dry proton conduction term (?0) and the activation enthalpy (?Hwet) are derived with tight bounds, and are both within the broader 2? errors of the different laboratory measurements. The two other terms used by the experimentalists, one to describe proton hopping (exponent ron pre-exponent water contentCw) and the other to describe H2O concentration-dependent activation enthalpy (term?Cw1/3 added to the activation energy), are less well defined and further field geophysical and petrological observations are required, especially in regions of higher temperature and higher water content.

Jones, Alan G.; Fullea, Javier; Evans, Rob L.; Muller, Mark R.

2012-06-01

177

Research and Laboratory Instruction--An Experiment in Teaching  

ERIC Educational Resources Information Center

Describes an attempt to incorporate research into laboratory work in an introductory ecology class and a senior seminar. The investigation involves the examination of rhythms of food consumption and circadian activities in humans. (GS)

Kramm, Kenneth R.

1976-01-01

178

Abstract We conducted a food supplementation field experiment to test two hypotheses: (1) fecundity of the  

E-print Network

of ecology's major themes. The concept is central to theories of how animals forage, how populations growAbstract We conducted a food supplementation field experiment to test two hypotheses: (1) fecundity

Illinois at Chicago, University of

179

Payload specialists Garneau and Scully-Power prior to conducting experiments  

NASA Technical Reports Server (NTRS)

Payload specialists Marc Garneau and Paul Scully-Power are pictured prior to conducting Canadian experiments in the Challenger's middeck. Between the two payload specialists is the treadmill exercise device.

1984-01-01

180

Summary of recent experiments on focusing of target-normal-sheath-accelerated proton beam with a stack of conducting foilsa)  

NASA Astrophysics Data System (ADS)

We present a summary of recent experiments on focusing of laser target-normal-sheath-accelerated (TNSA) proton beam with a stack of thin conducting foils. The experiments were performed using the Phelix laser (GSI-Darmstadt) and the Titan laser, Lawrence Livermore National Laboratory. The phenomena consistent with self-collimation (or weak self-focusing) of TNSA protons were experimentally observed for the first time at the Phelix laser user facility, in a specially engineered structure ("lens") consisting of a stack of 300 thin aluminum foils separated by 50 ?m vacuum gaps. Follow up experiments using the Titan laser obtained results consistent with the collimation/focusing observed in the initial experiments using the Phelix. The Titan experiments employed improved, 25 ?m- and 50 ?m-gap targets and the new fine mesh diagnostic. All the experiments were carried out in a "passive environment," i.e., no external fields were applied, and no neutralization plasma or injection of secondary charged particles was imposed. A plausible interpretation of the observed phenomena is that the combination of magnetic self-pinch forces generated by the beam current together with the simultaneous reduction of the repulsive electrostatic forces due to the conducting foils inhibits radial expansion of the beam.

Ni, P. A.; Alexander, N.; Barnard, J. J.; Lund, S. M.

2014-05-01

181

Decision-making under uncertainty: results from an experiment conducted at EGU 2012  

NASA Astrophysics Data System (ADS)

Do probabilistic forecasts lead to better decisions? At the EGU General Assembly 2012, we conducted a laboratory-style experiment to address this question. Several cases of flood forecasts and a choice of actions to take were presented as part of a game to participants, who acted as decision makers. Participants were prompted to make decisions when forecasts were provided with and without uncertainty information. They had to decide whether to open or not a gate which was the inlet of a retention basin designed to protect a town. The rules were such that: if they decided to open the gate, the retention basin was flooded and the farmers in this basin demanded a compensation for flooding their land; if they decided not to open the gate and a flood occurred on the river, the town was flooded and they had to pay a fine to the town. Participants were encouraged to keep note of their individual decisions in a worksheet. About 100 worksheets were collected at the end of the game and the results of their evaluation are presented here. In general, they show that decisions are based on a combination of what is displayed by the expected (forecast) value and what is given by the uncertainty information. In the absence of uncertainty information, decision makers are compelled towards a more risk-averse attitude. Besides, more money was lost by a large majority of participants when they had to make decisions without uncertainty information. Limitations of the experiment setting are discussed, as well as the importance of the development of training tools to increase effectiveness in the use of probabilistic predictions to support decisions under uncertainty.

Ramos, Maria-Helena; van Andel, Schalk Jan; Pappenberger, Florian

2013-04-01

182

Laboratory experiment on poroelastic behavior of Berea sandstone under two-phase fluid flow condition  

NASA Astrophysics Data System (ADS)

Coupled two-phase fluid flow and deformation of Berea sandstone was discussed through laboratory experiments and numerical simulation. In the experiment, a triaxial compression apparatus with flow pipes to pass fluids through a rock sample was used. The experimental procedures were as follows. Firstly, external stresses close to hydrostatic condition were applied to a water saturated cylindrical Berea sandstone sample. Then, compressed air was infiltrated from the bottom of the sample. During the experiment, both axial and circumferential strains at half the height of the sample and volumetric discharge of water at the outlet were measured. Both strains showed sudden extensions after a few seconds, and monotonically extended thereafter. The volumetric discharge of water showed that air breakthrough occurred in around 100 seconds after the commencement of the air injection. Numerical simulations based on thermodynamically consistent constitutive equations were conducted in order to quantitatively analyze the experimental results. In a simulation in which the material was assumed to be homogeneous isotropic, the axial strain at half the height of the sample and the volumetric discharge of water at the outlet were reproduced well by using reasonable parameters, while that was not the case with the circumferential strain at half the height of the sample. On the other hand, in a simulation in which anisotropy of the material was introduced, all experimental data were reproduced well by using reasonable parameters. This result is reasonable because Berea sandstone is well known to be anisotropic under such Terzaghi effective stress condition as used in our experiment, i.e., 3.0 MPa (Hart and Wang, 1999; Hart, 2000). Our results indicate that the theory of poroelasticity for two-phase fluid system can explain the strain behavior of porous media for two-phase fluid flow observed in laboratory experiments.

Goto, H.; Aichi, M.; Tokunaga, T.; Yamamoto, H.; Ogawa, T.; Aoki, T.

2013-12-01

183

Laboratory scaled simulation of lidar cloud sounding experiments  

NASA Technical Reports Server (NTRS)

The results of lidar measurements carried out on laboratory scale models of clouds are presented. Measurements on laboratory scale models are important since one has the knowledge of the relevant parameters of the diffusing medium, such as: scattering and absorption coefficients, phase function, homogeneity, shape, etc. Knowledge of these parameters enables one to use the results to test the reliability of theoretical and numerical investigations. To obtain a laboratory scaled model of a lidar system sounding a cloud, it is necessary to scale down all the geometrical quantities by the same factor to reduce distances of the order of kilometers to the order of meters, keeping the size and the optical depth of the diffusers unchanged. If a time resolution of the order of nanoseconds is necessary for a lidar sounding actual clouds, the corresponding time resolution for the laboratory model should be of the order of picoseconds. It is possible to obtain this resolution by using picosecond laser systems and fast electrooptical detectors like the streak camera. The results of the laboratory measurements showed that the multiple scattering effect strongly depends on the size of the diffusers, as well as on the concentration. The experimental results were compared with the numerical results of a Monte Carlo code. A generally good agreement was obtained.

Zaccanti, G.; Bruscaglioni, P.; Gurioli, M.; Sansoni, P.

1992-01-01

184

Data analysis of Einstein-Podolsky-Rosen-Bohm laboratory experiments  

E-print Network

Data sets produced by three different Einstein-Podolsky-Rosen-Bohm (EPRB) experiments are tested against the hypothesis that the statistics of this data is described by quantum theory. Although these experiments generate data that violate Bell inequalities for suitable choices of the time-coincidence window, the analysis shows that it is highly unlikely that these data sets are compatible with the quantum theoretical description of the EPRB experiment, suggesting that the popular statements that EPRB experiments agree with quantum theory lack a solid scientific basis and that more precise experiments are called for.

H. De Raedt; F. Jin; K. Michielsen

2013-12-22

185

Electrical conductivity in granular media and Branly's coherer: A simple experiment  

E-print Network

- mogeneous media such as granular media, as well as the influence of electromagnetic wavesElectrical conductivity in granular media and Branly's coherer: A simple experiment Eric Falcona experiment can illustrate certain electrical transport properties of metallic granular media. At a low

Falcon, Eric

186

Laboratory experiment on EM backscatter from Farley-Buneman and gradient drift waves  

SciTech Connect

Results are reported of a laboratory experiment on Bragg backscatter of 3-cm microwaves by turbulent waves driven by the Farley-Buneman and gradient drift instabilities. The present work is the third in a series of laboratory experiments performed to test, under controlled conditions, prevalent ideas on EM scattering equatorial and high-latitude ionospheric waves and irregularities.

Alport, M.J.; D'Angelo, N.; Pecseli, H.L.

1981-09-01

187

Redefining Authentic Research Experiences in Introductory Biology Laboratories and Barriers to Their Implementation  

ERIC Educational Resources Information Center

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are…

Spell, Rachelle M.; Guinan, Judith A.; Miller, Kristen R.; Beck, Christopher W.

2014-01-01

188

Wave-induced chaotic radial transport of energetic electrons in a laboratory terrella experiment  

E-print Network

Wave-induced chaotic radial transport of energetic electrons in a laboratory terrella experiment H-induced chaotic radial transport of energetic electrons in a laboratory terrella, the Collisionless Terrella Experiment (CTX) [H. P. Warren and M. E. Mauel, Phys. Rev. Lett. 74, 1351 (1995)]. Electron cyclotron

Mauel, Michael E.

189

PPPL-3441 PPPL-3441 Laboratory Experiments on Arc Deflection and Instability  

E-print Network

normal operation. Thus we had reasons to believe that arc deflection and instability can be controlledPPPL-3441 PPPL-3441 UC-70 Laboratory Experiments on Arc Deflection and Instability by Stewart-8547 Internet: http://www.ntis.gov/ordering.htm #12;1 Laboratory Experiments on Arc Deflection and Instability

190

Feasibility study to conduct windblown sediment experiments aboard a space station  

NASA Technical Reports Server (NTRS)

A feasibility study was undertaken to determine if a suitable apparatus could be designed to analyze aeolian processes for operation in space and to assess the feasibility of conducting meaningful experiments to address key aspects of aeolian processes. To meet this objective a prototype apparatus was fabricated and some limited experiments were run to determine its suitability for this application. At least three general types of experiments were devised that could be carried out aboard a space station: threshold studies, swirl (dust devil) experiments, and analyses of windblown particle trajectories. How experiments in a zero-g environment could advance knowledge of aeolian processes was studied.

Greeley, R.; Iversen, J. D.

1983-01-01

191

Laboratory Animal Science Issues in the Design and Conduct of Studies with Endocrine-active Compounds  

Microsoft Academic Search

The use of rodent models for research and testing on endo- crine-active compounds necessitates an awareness of a number of laboratory animal science issues to standardize bioassay methods and facilitate reproducibility of results between laboratories. These issues are not unique to endo- crine research but are particularly important in this field due to the complexities and interdependencies of the endocrine

Jeffrey I. Everitt; Paul M. D. Foster

2004-01-01

192

Graduate School of Pharmaceutical Sciences, Laboratory of Chemical Pharmacology Action-Potential Modulation During Axonal Conduction  

E-print Network

2010-1-31 Graduate School of Pharmaceutical Sciences, Laboratory of Chemical Pharmacology Action) Laboratory of Chemical Pharmacology Graduate School of Pharmaceutical Sciences The University of Tokyo" research area of the Japan Science and Technology Agency's Basic Research Programs (PRESTO). The results

Imai, Hiroshi

193

STAR: Preparing future science and math teachers through authentic research experiences at national laboratories  

NASA Astrophysics Data System (ADS)

The STEM Teacher and Researcher (STAR) Program provides 9-week paid summer research experiences at national research laboratories for future science and math teachers. The program, run by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the entire California State University (CSU) System, has arranged 290 research internships for 230 STEM undergraduates and credential candidates from 43 campuses over the past 6 years. The program has partnered with seven Department of Energy labs, four NASA centers, three NOAA facilities, and the National Optical Astronomy Observatory (NOAO). Primary components of the summer experience include a) conducting research with a mentor or mentor team, b) participating in weekly 2-3 hour workshops focused on translating lessons learned from summer research into classroom practice, and c) presenting a research poster or oral presentation and providing a lesson plan linked to the summer research experience. The central premise behind the STAR Program is that future science and math teachers can more effectively prepare the next generation of science, math, and engineering students if they themselves have authentic experiences as researchers.

Keller, John; Rebar, Bryan

2012-11-01

194

Restructuring a General Microbiology Laboratory into an Investigative Experience.  

ERIC Educational Resources Information Center

Describes an investigative laboratory sequence based upon the isolation and characterization of soil bacteria to aid microbiology teachers in providing students with activities that expose them to basic techniques of microbiology as well as demonstrates the scientific process and the experimental analysis of microorganisms. (ZWH)

Deutch, Charles E.

1994-01-01

195

Students' Experience in a General Chemistry Cooperative Problem Based Laboratory  

ERIC Educational Resources Information Center

Most educators and scientists would agree that science laboratory instruction has the potential of developing science practices fundamental to achieving scientific literacy. However, there is scant evidence to support that this potential is realized, particularly in tertiary level education. This paper reports qualitative results from a sequential…

Sandi-Urena, Santiago; Cooper, Melanie M.; Gatlin, Todd A.; Bhattacharyya, Gautam

2011-01-01

196

Interactive Screen Experiments--Innovative Virtual Laboratories for Distance Learners  

ERIC Educational Resources Information Center

The desirability and value of laboratory work for physics students is a well-established principle and issues arise where students are inherently remote from their host institution, as is the case for the UK's Open University. In this paper, we present developments from the Physics Innovations Centre for Excellence in Teaching and Learning…

Hatherly, P. A.; Jordan, S. E.; Cayless, A.

2009-01-01

197

Limits on Lithospheric Stress Imposed by Laboratory Experiments  

Microsoft Academic Search

Laboratory measurements of rock strength provide limiting values of lithospheric stress, provided that one effective principal stress is known. Fracture strengths are too variable to be useful; however, rocks at shallow depth are probably fractured so that frictional strength may apply. A single linear friction law, termed Byedee's law, holds for all materials except clays, to pressures of more than

W. F. Brace; D. L. Kohlstedt

1980-01-01

198

Experimenting from a Distance--Remotely Controlled Laboratory (RCL)  

ERIC Educational Resources Information Center

The use of computers and multimedia, as well as the World Wide Web and new communication technologies, allows new forms of teaching and learning such as distance learning, blended learning, use of virtual libraries and many more. The herewith discussed remotely controlled laboratory (RCL) project shall offer an additional contribution. The basic…

Grober, Sebastian; Vetter, Martin; Eckert, Bodo; Jodl, Hans-Jorg

2007-01-01

199

EXPERIMENTS ON BUOYANT PLUME DISPERSION IN A LABORATORY CONVENTION TANK  

EPA Science Inventory

Buoyant plume dispersion in the convective boundary layer (CBL) is investigated experimentally in a laboratory convection tank. The focus is on highly-buoyant plumes that loft near the CBL capping inversion and resist downward mixing. Highly- buoyant plumes are those with dimen...

200

Microcomputer-Based Digital Signal Processing Laboratory Experiments.  

ERIC Educational Resources Information Center

Describes a system (Apple II microcomputer interfaced to flexible, custom-designed digital hardware) which can provide: (1) Fast Fourier Transform (FFT) computation on real-time data with a video display of spectrum; (2) frequency synthesis experiments using the inverse FFT; and (3) real-time digital filtering experiments. (JN)

Tinari, Jr., Rocco; Rao, S. Sathyanarayan

1985-01-01

201

A "Greenhouse Gas" Experiment for the Undergraduate Laboratory  

ERIC Educational Resources Information Center

This experiment and analysis offer an effective experience in greenhouse gas reduction. Ammoniated water is flowed counter-current to a simulated flue gas of air and CO2 in a packed column. The gaseous CO2 concentrations are measured with an on-line, non- dispersive, infrared analyzer. Column operating parameters include total gas flux, dissolved…

Gomez, Elaine; Paul, Melissa; Como, Charles; Barat, Robert

2014-01-01

202

Training related research and development conducted at Oak Ridge National Laboratory for the US Nuclear Regulatory Commission  

Microsoft Academic Search

For a number of years Oak Ridge National Laboratory (ORNL) has conducted a sizeable program of human factors research and development in support of the Office of Nuclear Regulatory Research of the US Nuclear Regulatory Commission (NRC). The history of this effort has in many ways paralleled the growth of human factors R and D throughout the nuclear industry and

Haas

1985-01-01

203

The plasma dynamics of hypersonic spacecraft: Applications of laboratory simulations and active in situ experiments  

NASA Technical Reports Server (NTRS)

Attempts to gain an understanding of spacecraft plasma dynamics via experimental investigation of the interaction between artificially synthesized, collisionless, flowing plasmas and laboratory test bodies date back to the early 1960's. In the past 25 years, a number of researchers have succeeded in simulating certain limited aspects of the complex spacecraft-space plasma interaction reasonably well. Theoretical treatments have also provided limited models of the phenomena. Several active experiments were recently conducted from the space shuttle that specifically attempted to observe the Orbiter-ionospheric interaction. These experiments have contributed greatly to an appreciation for the complexity of spacecraft-space plasma interaction but, so far, have answered few questions. Therefore, even though the plasma dynamics of hypersonic spacecraft is fundamental to space technology, it remains largely an open issue. A brief overview is provided of the primary results from previous ground-based experimental investigations and the preliminary results of investigations conducted on the STS-3 and Spacelab 2 missions. In addition, several, as yet unexplained, aspects of the spacecraft-space plasma interaction are suggested for future research.

Stone, N. H.; Samir, Uri

1986-01-01

204

Laboratory Experiment of Plasma Flow Around Magnetic Sail  

Microsoft Academic Search

To propel a spacecraft in the direction leaving the Sun, a magnetic sail (MagSail) blocks the hypersonic solar wind plasma\\u000a flow by an artificial magnetic field. In order to simulate the interaction between the solar wind and the artificially deployed\\u000a magnetic field produced around a magnetic sail spacecraft, a laboratory simulator was designed and constructed inside a space\\u000a chamber. As

Ikkoh Funaki; Hidenori Kojima; Hiroshi Yamakawa; Yoshinori Nakayama; Yukio Shimizu

2007-01-01

205

Reflectance Experiment Laboratory (RELAB) Description and User's Manual  

NASA Technical Reports Server (NTRS)

Spectroscopic data acquired in the laboratory provide the interpretive foundation upon which compositional information about unexplored or unsampled planetary surfaces is derived from remotely obtained reflectance spectra. The RELAB is supported by NASA as a multi-user spectroscopy facility, and laboratory time can be made available at no charge to investigators who are in funded NASA programs. RELAB has two operational spectrometers available to NASA scientists: 1) a near- ultraviolet, visible, and near-infrared bidirectional spectrometer and 2) a near- and mid- infrared FT-IR spectrometer. The overall purpose of the design and operation of the RELAB bidirectional spectrometer is to obtain high precision, high spectral resolution, bidirectional reflectance spectra of earth and planetary materials. One of the key elements of its design is the ability to measure samples using viewing geometries specified by the user. This allows investigators to simulate, under laboratory conditions, reflectance spectra obtained remotely (i.e., with spaceborne, telescopic, and airborne systems) as well as to investigate geometry dependent reflectance properties of geologic materials. The Nicolet 740 FT-IR spectrometer currently operates in reflectance mode from 0.9 to 25 Fm. Use and scheduling of the RELAB is monitored by a 4-member advisory committee. NASA investigators should direct inquiries to the Science Manager or RELAB Operator.

Pieters, Carle M.; Hiroi, Takahiro; Pratt, Steve F.; Patterson, Bill

2004-01-01

206

Laptops in Psychology: Conducting Flexible In-Class Research and Writing Laboratories  

ERIC Educational Resources Information Center

This chapter describes an undergraduate psychology research methods course in which laptops facilitated online organization, electronic portfolios, and flexible laboratories to improve student engagement, capability, and understanding. (Contains 3 figures.)

Stephens, Benjamin R.

2005-01-01

207

LABORATORY AND FIELD RESULTS LINKING HIGH CONDUCTIVITIES TO THE MICROBIAL DEGRADATION OF PETROLEUM HYDROCARBONS  

EPA Science Inventory

The results of a field and laboratory investigation of unconsolidated sediments contaminated by petroleum hydrocarbons and undergoing natural biodegradation are presented. Fundamental to geophysical investigations of hydrocarbon impacted sediments is the assessment of how microbi...

208

Using Microcomputers in the Physical Chemistry Laboratory: Activation Energy Experiment.  

ERIC Educational Resources Information Center

Describes a computer program, "Activation Energy," which is designed for use in physical chemistry classes and can be modified for kinetic experiments. Provides suggestions for instruction, sample program listings, and information on the availability of the program package. (ML)

Touvelle, Michele; Venugopalan, Mundiyath

1986-01-01

209

4,5-Diphenyl-1-methylimidazole: An Undergraduate Laboratory Experiment.  

ERIC Educational Resources Information Center

Background information and procedures used are provided for the synthesis of 4,5-diphenyl-methylimidazole. This experiment on the chemistry of heterocycles is ideally suited for beginning undergraduate organic chemistry students. (JN)

Anastas, Paul T.; And Others

1985-01-01

210

The Semipermeability of Biological Membranes: An Undergraduate Laboratory Experiment.  

ERIC Educational Resources Information Center

The semipermeability of biological membranes is simply and directly illustrated in an experiment which uses ovolecithin liposomes as convenient models for biological membranes. Background information and procedures used are provided. (JN)

Frimer, Aryeh A.

1985-01-01

211

Effect of Bacillus subtilis on Granite Weathering: A Laboratory Experiment  

Microsoft Academic Search

We performed a comparative experiment to investigate how the ubiquitous soil bacterium Bacillus subtilis weathers granite and which granite-forming minerals weather more rapidly via biological processes. Batch type experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria Bacillus subtilis at 27°E C) were carried out for 30 days. Granite surfaces were observed by SEM

W. Song; N. Ogawa; C. T. Oguchi; T. Hatta; Y. Matsukura

2006-01-01

212

Effect of Bacillus subtilis on granite weathering: A laboratory experiment  

Microsoft Academic Search

We performed a comparative experiment to investigate: (1) how the ubiquitous soil bacterium Bacillus subtilis weathers granite; and (2) which granite-forming minerals weather more rapidly via biological processes. Batch system experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria B. subtilis at 27 °C) were carried out for 30 days. Granite surfaces were observed by SEM before

W. Song; N. Ogawa; C. T. Oguchi; T. Hatta; Y. Matsukura

2007-01-01

213

Absorption spectroscopy of a laboratory photoionized plasma experiment at Z  

NASA Astrophysics Data System (ADS)

The Z facility at the Sandia National Laboratories is the most energetic terrestrial source of X-rays and provides an opportunity to produce photoionized plasmas in a relatively well characterised radiation environment. We use detailed atomic-kinetic and spectral simulations to analyze the absorption spectra of a photoionized neon plasma driven by the x-ray flux from a z-pinch. The broadband x-ray flux both photoionizes and backlights the plasma. In particular, we focus on extracting the charge state distribution of the plasma and the characteristics of the radiation field driving the plasma in order to estimate the ionisation parameter.

Hall, I. M.; Durmaz, T.; Mancini, R. C.; Bailey, J. E.; Rochau, G. A.; Golovkin, I. E.; MacFarlane, J. J.

2014-03-01

214

Practical advice for conducting ethical online experiments and questionnaires for United States psychologists  

Microsoft Academic Search

It is increasingly easy and, therefore, increasingly common to conduct experiments and questionnaire studies in online environments.\\u000a However, the online environment is not a data collection medium that is familiar to many researchers or to many research methods\\u000a instructors. Because of this, researchers have received little information about how to address ethical issues when conducting\\u000a online research. Researchers need practical

Kimberly A. Barchard; John Williams

2008-01-01

215

Effect of Bacillus subtilis on Granite Weathering: A Laboratory Experiment  

NASA Astrophysics Data System (ADS)

We performed a comparative experiment to investigate how the ubiquitous soil bacterium Bacillus subtilis weathers granite and which granite-forming minerals weather more rapidly via biological processes. Batch type experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria Bacillus subtilis at 27°E C) were carried out for 30 days. Granite surfaces were observed by SEM before and after the experiment. Bacillus subtilis had a strong influence on granite weathering by forming pits. There were 2.4 times as many pits and micropores were 2.3 times wider in granite exposed to Bacillus subtilis when compared with bacteria-free samples. Bacillus subtilis appear to preferentially select an optimum place to adhere to the mineral and dissolve essential elements from the mineral to live. Plagioclase was more vulnerable to bacterial weathering than biotite among the granite composing minerals.

Song, W.; Ogawa, N.; Oguchi, C. T.; Hatta, T.; Matsukura, Y.

2006-12-01

216

Epigenetics of Complex Diseases: From General Theory to Laboratory Experiments  

Microsoft Academic Search

Despite significant effort, understanding the causes and mechanisms of complex non-Mendelian diseases remains a key challenge.\\u000a Although numerous molecular genetic linkage and association studies have been conducted in order to explain the heritable\\u000a predisposition to complex diseases, the resulting data are quite often inconsistent and even controversial. In a similar way,\\u000a identification of environmental factors causal to a disease is

A. Schumacher; A. Petronis

217

An outsider's experiences in conducting field research in an African-American community.  

PubMed

Researchers agree that the conduct of field research is a challenging and enlightening experience. This article describes an African-American (AA) researcher's experiences in accessing and conducting field research in an AA community. These experiences were from a Grounded Theory (GT) qualitative research study to understand the social contexts and processes, and other interrelated factors such as beliefs in God or a higher being and role expectations on mammography-screening decision-making in older, urban AA women of various socioeconomic strata. The field experience of accessing and recruiting AA women into a GT study were partly influenced by two prior historical studies conducted by the Federal government that resulted in violation of human rights. These historical experiences greatly impacted the researcher's entrée into the AA community and success in conducting the GT study. The researcher realized the benefit of establishing professional relationship with key informants (church nurses) for the success of accessing and recruiting individuals into research studies. Of utmost importance, the researcher was viewed as an "outsider" and represented the separate, distinct world of the university. Particularly noteworthy was the fact that holding the same ethnicity of the AA community does not guarantee automatic initial or ongoing entrée into the community or recruitment of participants. PMID:12242748

Fowler, Barbara A

2002-07-01

218

Electrical conductivity in a partially molten lower crust from laboratory measurements on xenoliths (El Hoyazo, SE Spain)  

NASA Astrophysics Data System (ADS)

The presence of High Conductive Zones (HCZs) within the lower crust is explained by several mechanisms involving phases as graphite, brines and partial melts, which enhance the conductivity when inteconnected over large distances. In the Internal Betics (Southern Spain) the anomalous HCZ imaged at the bottom of a thinned lower crust (Pous et al., 1999) is combined with low seismic velocities and high heat flow values (Carbonell et al., 1998) supporting the hypothesis that partial melts are present at depths. This is further confirmed by the recovery of restitic lower crustal xenoliths retaining evidence of partial melting (Zeck, 1968). The xenolith also contain up to 2 wt% of graphite which may contribute to the conductivity enhancement. The present study is focused on the electrical conductivity at high pressure and temperature of four garnet-biotite-sillimanite metapelitic xenoliths collected from the Neogene dacites of El Hoyazo (SE Spain). The paragenesis is represented by garnet + biotite + sillimanite + plagioclase ± cordierite coexisting with graphite and widespread rhyolitic melt as inclusions and interstitial glass (~10 wt%) (Cesare & Gómez-Pugnaire, 2001). The assemblage developed during regional anatexis at 850-900°C and 500 - 700 MPa (Cesare et al., 1997) and melt was frozen-in during fast uplift. In order to discriminate the contibution of graphite and melt, assess the effect of their geometrical distribution and infer the influence of the glass rheology to the electrical conductivity, experiments were performed in two gas apparata at sealed and unsealed conditions. In unsealed runs, in fact, the porosity remains open which prevents graphite reconnection. The sealed experiments were conducted in a Paterson Apparatus up to 680°C and 840°C at 100 MPa and to 900°C at 300 MPa, the unsealed ones in an internally heated gas apparatus (IHPV) with Ar as pressure medium up to 950°C and 400 MPa. For each sample three mutually orthogonal cores (X, Y, Z) were drilled parallel to the macroscopic fabric elements to determine the electrical anisotropy: X parallel to lineation and Z normal to foliation. Two electrodes were placed on the top and the bottom surfaces of the cores in a two pole arrangement in both the Paterson apparatus and the HIPV. In the Paterson apparatus, Nickel electrodes were used together with iron jackets to control the oxygen fugacity and temperature was monitored with one K-type thermocouple soldered on one of the two electrodes. In the IHPV two Platinum discs were connected to Pt and PtRh wires as S-type thermocouples. An authomated impedance spectrometer was used to collect the resistivity values in the range 1-105 Hz. The Arrhenius plot of the Logarithmic specific conductivity versus the reciprocal absolute temperature, evidence that the electrical properties are remarkably similar in unsealed and sealed runs up to 700°C and linear above 400°C with an activation energy Ea =0.340 ÷ 0.561 eV. At 700°C, in unsealed experiments Ea increases to 1.03 ÷ 1.34 eV and a single impedance arc is observed at every temperature. In sealed experiments, the increment of Ea at 700°C is higher, up to 1.64 eV, and two impedance arcs (along direction X) or three (along Y) are observed. Melting occurs at T>800°C with the production of very tiny spinel + biotite + plagioclase + melt. At 700°C a phase interconnection is achieved which may be related to the glass transition temperature Te of the initial glass. The laboratory measurements are consistent with the magnetotelluric soundings at temperature of 800-880°C and compatible with the hypothesis that partial melts are present in the Alborán lower crust. This temperature value is important to constraint the actual geotherm in the area. REFERENCES Carbonell R., Sallarés V., Puos J., Dañobeitia J.J., Queralt P., Ledo J.J. and Dueñas G. Tectonophysics, 288: 137-152, 1998 Cesare B., Salvioli Mariani E. and Venturelli G., Mineral. Magaz. 61 (1): 15-27, 1997 Cesare B. & Gómez-Pugnaire M. T., Phys. Chem. Earth (A), 26 (4-5): 255-260, 2001 Holtz

Ferri, F.; Gibért, B.; Violay, M.; Schilling, F. R.; Cesare, B.

2009-04-01

219

IRAS mission operations experience at RAL (Rutherford Appleton Laboratory)  

Microsoft Academic Search

The Infra Red Astronomical Satellite (IRAS) was launched in January 1983. During its 300-day lifetime IRAS carried out a complete survey of the sky at infrared wavelengths and also made about 14,000 additional observations of selected sources. This paper presents a summary of the development of the ground operations hardware and software, and discusses the experience gained during IRAS mission

J. R. MacDougall; P. H. McPherson; K. E. Mount; G. R. Thomas

1984-01-01

220

Ion Exchange Chromatography and Spectrophotometry: An Introductory Undergraduate Laboratory Experiment.  

ERIC Educational Resources Information Center

Describes an experiment in which students use ion exchange chromatography to separate a mixture of chloro complexes of transition metal ions and then use spectrophotometry to define qualitatively the efficiency of the ion exchange columns. Background information, materials needed, and procedures used are included. (JN)

Foster, N.; And Others

1985-01-01

221

Cavity Ring down Spectroscopy Experiment for an Advanced Undergraduate Laboratory  

ERIC Educational Resources Information Center

A simple experiment is described that permits advanced undergraduates to learn the principles and applications of the cavity ring down spectroscopy technique. The apparatus is used for measurements of low concentrations of NO[subscript 2] produced in air by an electric discharge. We present the setup, experimental procedure, data analysis and some…

Stacewicz, T.; Wasylczyk, P.; Kowalczyk, P.; Semczuk, M.

2007-01-01

222

Molecular Velocity Determination through Gas Effusion: Intermediate Laboratory Experiment  

Microsoft Academic Search

An experiment is described to determine the average velocity of gas molecules in a container while effusion takes place through a small hole into vacuum. When the mean free path of the molecules becomes large compared to the hole diameter, the measurement of pressure as a function of time permits the average velocity to be extracted. The equipment and procedure

R. E. Benenson

1969-01-01

223

Experiments using a microcomputer in a school laboratory  

NASA Astrophysics Data System (ADS)

A computer can be used as a storage oscilloscope with an AD converter and suitable software. Experiments are described using a PC-compatible computer and a data acquisition and handling system. The electronic equipment and software are now commercially available.

Nilsson, Örjan; Petersson, Lars-Olof; Carlsson, Per-Olof

1992-01-01

224

Experimenting in a Constructivist High School Physics Laboratory  

NSDL National Science Digital Library

Presents a study involving students (n=46) enrolled in an introductory physics course designed to describe and understand students' experimenting and problem-solving strategies in a constructivist learning environment. Concludes that students should be provided with problem-rich learning environments in which they learn to investigate phenomena of their own interest and can develop complex problem-solving skills.

Roth, Wolff-Michael

2006-10-09

225

User Experience in Digital Games: Differences between Laboratory and Home  

ERIC Educational Resources Information Center

Playing entertainment computer, video, and portable games, namely, digital games, is receiving more and more attention in academic research. Games are studied in different situations with numerous methods, but little is known about if and how the playing situation affects the user experience (UX) in games. In addition, it is hard to understand and…

Takatalo, Jari; Hakkinen, Jukka; Kaistinen, Jyrki; Nyman, Gote

2011-01-01

226

Role of Organic Acids in Bioformation of Kaolinite: Results of Laboratory Experiments  

NASA Astrophysics Data System (ADS)

Clay minerals and other solid silica phases have a broad distribution in the geological record and greatly affect fundamental physicochemical properties of sedimentary rocks, including porosity. An increasing number of studies suggests that microbial activity and microbially produced organic acids might play an important role in authigenic clay mineral formation, at low temperatures and under neutral pH conditions. In particular, early laboratory experiments (Linares and Huertas, 1971) reported the precipitation of kaolinite in solutions of SiO2 and Al2O3 with different molar ratios SiO2/Al2O3, together with fulvic acid (a non-characterized mixture of many different acids containing carboxyl and phenolate groups) that was extracted from peat soil. Despite many attempts, these experiments could not be reproduced until recently. Fiore et al. (2011) hypothesized that the non-sterile fulvic acid might have contained microbes that participated in the formation of kaolinite. Using solutions saturated with Si and Al and containing oxalate and/or mixed microbial culture extracted from peat-moss soil, they performed incubation experiments, which produced kaolinite exclusively in solutions containing oxalate and microbes. We proposed to test the role of specific organic acids for kaolinite formation, conducting laboratory experiments at 25?C, with solutions of sodium silicate, aluminum chloride and various organic compounds (i.e. EDTA, citric acid, succinic acid and oxalic acid). Specific organic acids may stabilize aluminum in octahedral coordination positions, which is crucial for the initial nucleation step. In our experiments, a poorly crystalline mineral that is possibly a kaolinite precursor formed exclusively in the presence of succinic acid. In experiments with other organic compounds, no incorporation of Al was observed, and amorphous silica was the only precipitated phase. In natural environments, succinic acid is produced by a large variety of microbes as an intermediate product of the tricarboxylic acid cycle. Our results demonstrate, for the first time, that the formation of a specific clay mineral (proto-kaolinite) occurs in the presence of a specific organic compound (succinic acid). This implies that microbial species capable of excreting succinate among their EPS may promote authigenic kaolinite formation at low temperature and neutral pH. This biological degradation process might play a crucial role for the formation of authigenic kaolinite, which is a widespread clay mineral in sedimentary environments. Fiore, S., Dumontet, S., Huertas, F.J., and Pasquale, V., 2011. Bacteria-induced crystallization of kaolinite. Applied Clay Science, 53:566-571. Linares, J., and Huertas, F., 1971. Kaolinite: Synthesis at room temperature. Science 171: 896-897.

Bontognali, T. R. R.; Vasconcelos, C.; McKenzie, J. A.

2012-04-01

227

Effect of ionic ordering in conductivity experiments of DNA aqueous solutions  

E-print Network

The effects of ionic ordering in DNA water solutions are studied by conductivity experiments. The conductivity measurements are performed for the solutions of DNA with KCl salt in the temperature range from 28 to 70 C. Salt concentration vary from 0 to 2 M. The conductivity of solutions without DNA but with the same concentration of KCl salt are also performed. The results show that in case of salt free solution of DNA the melting process of the double helix is observed, while in case of DNA solution with added salt the macromolecule denaturation is not featured. For salt concentrations lower than some critical one (0.4 M) the conductivity of DNA solution is higher than the conductivity of KCl water solution without DNA. Starting from the critical concentration the conductivity of KCl solution is higher than the conductivity of DNA solution with added salt. For description of the experimental data phenomenological model is elaborated basing on electrolyte theory. In framework of the developed model a mechanism of counterion ordering is introduced. According to this mechanism under the low salt concentrations electrical conductivity of the system is caused by counterions of DNA ion-hydrate shell. Increasing the amount of salt to the critical concentration counterions condense on DNA polyanion. Further increase of salt concentration leads to the formation of DNA-salt complexes that decreases the conductivity of the system.

O. O. Liubysh; O. M. Alekseev; S. Yu. Tkachov; S. M. Perepelytsya

2014-01-03

228

Radiative transfer theory verified by controlled laboratory experiments.  

PubMed

We report the results of high-accuracy controlled laboratory measurements of the Stokes reflection matrix for suspensions of submicrometer-sized latex particles in water and compare them with the results of a numerically exact computer solution of the vector radiative transfer equation (VRTE). The quantitative performance of the VRTE is monitored by increasing the volume packing density of the latex particles from 2% to 10%. Our results indicate that the VRTE can be applied safely to random particulate media with packing densities up to ?2%. VRTE results for packing densities of the order of 5% should be taken with caution, whereas the polarized bidirectional reflectivity of suspensions with larger packing densities cannot be accurately predicted. We demonstrate that a simple modification of the phase matrix entering the VRTE based on the so-called static structure factor can be a promising remedy that deserves further examination. PMID:24104804

Mishchenko, Michael I; Goldstein, Dennis H; Chowdhary, Jacek; Lompado, Arthur

2013-09-15

229

Improved laboratory diagnosis of tuberculosis--the Indian experience.  

PubMed

Tuberculosis (TB) is the leading cause of death worldwide attributable to a single infectious disease agent. India has more new TB cases annually than any other country. In 2008, India accounted for a fifth of the estimated 9.4 million TB cases globally. There is an overwhelming need for improving TB diagnostics in India through the use of cost effective, patient-friendly methods appropriate to different tiers of the country health system. Substantial progress has been made in India in the field of TB diagnosis and serious efforts have been made to herald the development of diagnostic tests for pulmonary TB, extra pulmonary TB and MDR-TB. Diverse approaches have been attempted towards improving smear microscopy, rapid culture and for differentiation between the Mycobacterium tuberculosis complex and non-tuberculous mycobacteria. Several laboratories have developed in-house PCR assays for diagnosing TB with high accuracy. Approaches for distinguishing M. tuberculosis and/or Mycobacterium bovis infection and disseminated Mycobacterium avium complex infection in HIV-AIDS patients have also been described. Serological tests to detect antigens or antibodies to M. tuberculosis specific components by using cocktails of Excretory/Secretory protein antigens, Ag85 complex antigens, Hsp 65 antigen, RD1 antigens and Rapid Reverse Line Blot Hybridization assays to detect MDR-TB (mutations to rifampicin, isoniazid and streptomycin) have also been developed. Other methods like measurement of adenosine deaminase activity and use of luciferase reporter phages have also been explored for TB diagnosis. These advances in the Indian context are detailed in the present chapter. The validation and application of these methods in laboratory and public health settings is likely to result in improved TB diagnosis and contribute to effective disease management in India. PMID:21764383

Haldar, Sagarika; Bose, Mridula; Chakrabarti, Parul; Daginawala, Hatim F; Harinath, B C; Kashyap, Rajpal S; Kulkarni, Savita; Majumdar, Anindita; Prasad, H Krishna; Rodrigues, Camilla; Srivastava, Ranjana; Taori, Girdhar M; Varma-Basil, Mandira; Tyagi, Jaya S

2011-09-01

230

DEVELOPMENT OF A SYSTEM FOR CONDUCTING INTER-LABORATORY TESTS FOR WATER QUALITY AND EFFLUENT MEASUREMENTS  

EPA Science Inventory

FMC Corporation has Developed a system for evaluating water pollution data and the laboratories which produce these data. The system consists of a plan for the design and implementation of an interlaboratory test program. A pilot test program was included to evaluate and to verif...

231

LABORATORY AND FIELD RESULTS LINKING HIGH CONDUCTIVITIES TO THE MICROBIAL DEGRADATION OF PETROLEUM HYDROCARBONS  

EPA Science Inventory

The results of a l6-month field and l6-month meso-scale laboratory investigation of unconsolidated sandy environments contaminated by petroleum hydrocarbons that are undergoing natural biodegradation is presented. The purpose was to understand the processes responsible for causin...

232

Designing and Conducting a Purification Scheme as an Organic Chemistry Laboratory Practical  

ERIC Educational Resources Information Center

An open-ended laboratory practical has been developed that challenges students to evaluate when different purification techniques are appropriate. In contrast to most lab practicals, the overall grade includes an evaluation of spectral analysis as well as writing skills. However, a significant portion of the grade lies in successful execution of a…

Graham, Kate J.; Johnson, Brian J.; Jones, T. Nicholas; McIntee, Edward J.; Schaller, Chris P.

2008-01-01

233

Benchmarking in a differentially heated rotating annulus experiment: Multiple equilibria in the light of laboratory experiments and simulations  

NASA Astrophysics Data System (ADS)

In the framework of the German Science Foundation's (DFG) priority program 'MetStröm' various laboratory experiments have been carried out in a differentially heated rotating annulus configuration in order to test, validate and tune numerical methods to be used for modeling large-scale atmospheric processes. This classic experimental set-up is well known since the late 1940s and is a widely studied minimal model of the general mid-latitude atmospheric circulation. The two most relevant factors of cyclogenesis, namely rotation and meridional temperature gradient are quite well captured in this simple arrangement. The tabletop-size rotating tank is divided into three sections by coaxial cylindrical sidewalls. The innermost section is cooled whereas the outermost annular cavity is heated, therefore the working fluid (de-ionized water) in the middle annular section experiences differential heat flow, which imposes thermal (density) stratification on the fluid. At high enough rotation rates the isothermal surfaces tilt, leading to baroclinic instability. The extra potential energy stored in this unstable configuration is then converted into kinetic energy, exciting drifting wave patterns of temperature and momentum anomalies. The signatures of these baroclinic waves at the free water surface have been analysed via infrared thermography in a wide range of rotation rates (keeping the radial temperature difference constant) and under different initial conditions (namely, initial spin-up and "spin-down"). Paralelly to the laboratory simulations of BTU Cottbus-Senftenberg, five other groups from the MetStröm collaboration have conducted simulations in the same parameter regime using different numerical approaches and solvers, and applying different initial conditions and perturbations for stability analysis. The obtained baroclinic wave patterns have been evaluated via determining and comparing their Empirical Orthogonal Functions (EOFs), drift rates and dominant wave modes. Thus certain "benchmarks" have been created that can later be used as test cases for atmospheric numerical model validation. Both in the experiments and in the numerics multiple equilibrium states have been observed in the form of hysteretic behavior depending on the initial conditions. The precise quantification of these state and wave mode transitions may shed light to some aspects of the basic underlying dynamics of the baroclinic annulus configuration, still to be understood.

Vincze, Miklos; Harlander, Uwe; Borchert, Sebastian; Achatz, Ulrich; Baumann, Martin; Egbers, Christoph; Fröhlich, Jochen; Hertel, Claudia; Heuveline, Vincent; Hickel, Stefan; von Larcher, Thomas; Remmler, Sebastian

2014-05-01

234

Laboratory studies of the electrical conductivity of silicate perovskites at high pressures and temperatures  

NASA Technical Reports Server (NTRS)

The electrical conductivities of two silicate perovskites and a perovskite-magnesiowuestite assemblage, all having an atomic ratio of Mg to Fe equal to 0.88/0.12, have been measured with alternating current and direct current (dc) techniques at simultaneously high pressures and temperatures. Measurements up to pressures of 80 GPa and temperatures of 3500 K, using a laser-heated diamond anvil cell, demonstrate that the electrical conductivity of these materials remains below 10-3 S/m at lower mantle conditions. The activation energies for electrical conduction are between 0.1 and 0.4 eV from the data, and the conduction in these perovskites is ascribed to an extrinsic electronic process. The new measurements are in agreement with a bound that was previously obtained from dc measurements for the high-PT conductivity of perovskite-dominated assemblages. The results show that the electrical conductivity of (Mg/0.88/Fe/0.12)SiO3 perovskite differs significantly from that of the earth's deep mantle, as inferred from geophysical observations.

Li, Xiaoyuan; Jeanloz, Raymond

1990-01-01

235

Using Coupled Mesoscale Experiments and Simulations to Investigate High Burn-Up Oxide Fuel Thermal Conductivity  

NASA Astrophysics Data System (ADS)

Nuclear energy is a mature technology with a small carbon footprint. However, work is needed to make current reactor technology more accident tolerant and to allow reactor fuel to be burned in a reactor for longer periods of time. Optimizing the reactor fuel performance is essentially a materials science problem. The current understanding of fuel microstructure have been limited by the difficulty in studying the structure and chemistry of irradiated fuel samples at the mesoscale. Here, we take advantage of recent advances in experimental capabilities to characterize the microstructure in 3D of irradiated mixed oxide (MOX) fuel taken from two radial positions in the fuel pellet. We also reconstruct these microstructures using Idaho National Laboratory's MARMOT code and calculate the impact of microstructure heterogeneities on the effective thermal conductivity using mesoscale heat conduction simulations. The thermal conductivities of both samples are higher than the bulk MOX thermal conductivity because of the formation of metallic precipitates and because we do not currently consider phonon scattering due to defects smaller than the experimental resolution. We also used the results to investigate the accuracy of simple thermal conductivity approximations and equations to convert 2D thermal conductivities to 3D. It was found that these approximations struggle to predict the complex thermal transport interactions between metal precipitates and voids.

Teague, Melissa C.; Fromm, Bradley S.; Tonks, Michael R.; Field, David P.

2014-10-01

236

Stable carbon and oxygen isotope fractionation processes during speleothem growth: systematic investigation in novel laboratory experiments  

NASA Astrophysics Data System (ADS)

The most widely applied climate proxies in speleothems are stable carbon and oxygen isotopes (?13C and ?18O). The interpretation of the stable isotope signals in terms of past temperature and/or precipitation variability is complex because both ?18O and ?13C depend on a complex interplay of various processes occurring in the atmosphere, the soil and karst above the cave and inside the cave. Quantitative reconstruction of climate parameters such as temperature and precipitation has, thus, remained impossible so far. Here we present several novel laboratory experiments aiming to understand the basic physical and chemical processes affecting the ?18O and ?13C signals during precipitation of calcium carbonate on the stalagmite surface. In particular, we aim to quantify the influence of kinetic isotope fractionation and verify recently published modelling studies (Dreybrodt, 2008; Scholz et al., 2009, Dreybrodt and Scholz, 2011). Several experiments are conducted: Degassing of CO2 from a thin film of water sparged with CO2 flowing down an inclined glass plate. pH and electric conductivity are systematically documented in order to monitor degassing of CO2. The results show that degassing of CO2 is fast, and the pCO2 of the solution is in equilibrium with the atmosphere after a short distance of flow. Carbon isotope exchange between atmospheric CO2 and dissolved bicarbonate. The results show that carbon isotope exchange may have a significant effect on the ?13C value of the dissolved bicarbonate and, thus, speleothem calcite, in particular for slow drip rates. Degassing of CO2 and calcite precipitation from a thin film of water supersaturated with respect to calcite flowing down an inclined calcium carbonate plate. Drip water is sampled after different lengths of flow path and, thus, different residence times on the plate, and pH, electrical conductivity and the stable isotope composition of the water are determined. Decreasing conductivity with increasing distance of flow path documents precipitation of calcium carbonate. We observe progressively increasing ?13C and ?18O values with increasing distance of flow in agreement with the model predictions. Calcite precipitation from a thin film of water supersaturated with respect to calcite flowing down an inclined glass plate. The precipitated calcite shows a clear enrichment in both ?13C and ?18O, and the absolute values are in good agreement with the stable isotope values of the dissolved bicarbonate (see experiment 3).

Scholz, D.; Hansen, M.; Dreybrodt, W.

2012-04-01

237

Cool in the Kitchen: Radiation, Conduction, and the Newton "Hot Block" Experiment.  

ERIC Educational Resources Information Center

Discusses the history of the development of Newton's Law of Cooling. Describes an experiment conducted in the kitchen that is designed to test the rate of cooling of a hot block of iron. Finds that Newton's law does not represent very well the mechanism of heat loss. (Contains over 10 references.) (WRM)

Silverman, Mark P.; Silverman, Christopher R.

2000-01-01

238

World's Oldest Cotton Experiment: Relationships between Soil Chemical and Physical Properties and Apparent Electrical Conductivity  

Microsoft Academic Search

Measuring and mapping apparent soil electrical conductivity (ECa) is a potentially useful tool for delineating soil variability. The “Old Rotation,” the world's oldest continuous cotton (Gossypium hirsutum L.) experiment (ca. 1896), provides a valuable resource for evaluating soil spatial variability. The objectives of this study were to determine the relationship between soil chemical and physical properties and ECa in the

D. W. Reeves; J. N. Shaw; C. C. Mitchell

2006-01-01

239

Do stable isotopes reflect nutritional stress? Results from a laboratory experiment on song sparrows.  

PubMed

Stable isotope analysis is an increasingly valuable tool in ecological studies and shows promise as a measure of nutritional stress in wild animals. Thus far, however, the only studies on endotherms that have conclusively shown changes in delta(15)N and delta(13)C values in response to nutritional stress were conducted on fasting animals and animals growing under extreme levels of food restriction. We conducted a laboratory experiment to test whether delta(15)N and delta(13)C values provide a general index of nutritional stress. We compared the isotopic composition of whole blood, liver, muscle and feathers between two groups of juvenile song sparrows (Melospiza melodia) hand-reared in captivity under identical conditions except for feeding regime. To verify that our experimental treatment induced a biologically meaningful level of nutritional stress, we simultaneously measured the effects on physiology, growth and development at multiple scales. While food-restricted birds were physiologically stressed, physically smaller, and showed poorer growth and brain development compared to ad libitum-fed birds, there was no effect of feeding regime on either delta(15)N or delta(13)C values in any tissue. Instead of a continuum where the level of change in (15)N or (13)C contents corresponds to the level of nutritional stress, we suggest there may be a threshold level of nutritional stress below which such isotopic changes are likely to be negligible. PMID:17102993

Kempster, Bethany; Zanette, Liana; Longstaffe, Fred J; MacDougall-Shackleton, Scott A; Wingfield, John C; Clinchy, Michael

2007-03-01

240

The Predominance of Self-shielding in Laboratory CO Photolysis Experiments  

NASA Astrophysics Data System (ADS)

I argue here that the laboratory CO photolysis results of Chakraborty et al. (2008) are, in fact, a result of CO self-shielding, and I present model simulations of several of their experiments as support.

Lyons, J. R.

2009-03-01

241

The Quartz-Crystal Microbalance in an Undergraduate Laboratory Experiment: I. Fundamentals and Instrumentation  

ERIC Educational Resources Information Center

The fundamentals, as well as the instrumentation of the quartz-crystal microbalance (QCM) technique that is used in an undergraduate laboratory experiment are being described. The QCM response can be easily used to change the properties of any system.

Tsionsky, Vladimir

2007-01-01

242

Screening for Saponins Using the Blood Hemolysis Test. An Undergraduate Laboratory Experiment.  

ERIC Educational Resources Information Center

Describes an experiment for undergraduate chemistry laboratories involving a chemical found in plants and some sea animals. Discusses collection and identification of material, a hemolysis test, preparation of blood-coated agar plates, and application of samples. (CW)

Sotheeswaran, Subramaniam

1988-01-01

243

Quantitative imaging of contaminant distributions in heterogeneous porous media laboratory experiments  

E-print Network

Quantitative imaging of contaminant distributions in heterogeneous porous media laboratory porous media properties or lighting nonuniformities. As a robust test, our image analysis package experiments on heterogeneous porous media have been increasingly used for the study of saturated

Barrash, Warren

244

Cross-Disciplinary Thermoregulation and Sweat Analysis Laboratory Experiences for Undergraduate Chemistry and Exercise Science Students  

NSDL National Science Digital Library

This article describes a qualitative evaluation of Cross-Disciplinary health sciences undergraduate laboratory experiences in which concepts and students from two distinct disciplines (chemistry and exercise physiology) combined to study exercise thermoregulation and sweat analysis.

2011-06-01

245

Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment: 1000-H Laboratory Test A.  

National Technical Information Service (NTIS)

A laboratory test program is described to evaluate the corrosion behavior of several metallic alloys, coatings, claddings, and weldments in support of the atmospheric fluidized-bed air heater experiment. Results are presented from the first 1000-h test (T...

K. Natesan, W. Podolski

1987-01-01

246

Ion acoustic wave experiments in a high school plasma physics laboratory Walter Gekelman  

E-print Network

Ion acoustic wave experiments in a high school plasma physics laboratory Walter Gekelman Department and faculty from UCLA constructed a plasma physics device and began research on ion acoustic waves. Plasma

California at Los Angles, University of

247

Insights into oil cracking based on laboratory experiments  

USGS Publications Warehouse

The objectives of this pyrolysis investigation were to determine changes in (1) oil composition, (2) gas composition and (3) gas carbon isotope ratios and to compare these results with hydrocarbons in reservoirs. Laboratory cracking of a saturate-rich Devonian oil by confined, dry pyrolysis was performed at T = 350-450??C, P = 650 bars and times ranging from 24 h to 33 days. Increasing thermal stress results in the C15+ hydrocarbon fraction cracking to form C6-14 and C1-5 hydrocarbons and pyrobitumen. The C6-14 fraction continues to crack to C 1-5 gases plus pyrobitumen at higher temperatures and prolonged heating time and the ?? 13Cethane-?? 13Cpropane difference becomes greater as oil cracking progresses. There is considerable overlap in product generation and product cracking. Oil cracking products accumulate either because the rate of generation of any product is greater than the rate of removal by cracking of that product or because the product is a stable end member under the experimental conditions. Oil cracking products decrease when the amount of product generated from a reactant is less than the amount of product cracked. If pyrolysis gas compositions are representative of gases generated from oil cracking in nature, then understanding the processes that alter natural gas composition is critical. ?? 2003 Elsevier Ltd. All rights reserved.

Hill, R.J.; Tang, Y.; Kaplan, I.R.

2003-01-01

248

Integrated laboratory scale demonstration experiment of S-I cycle  

SciTech Connect

The Sulfur Iodine thermochemical cycle for the production of hydrogen is one of the promising approaches for use with next generation high temperature advanced nuclear reactors. Within the framework of an international collaboration (I-NERI project) between the American DOE and the French CEA, the development of a laboratory scale hydrogen production loop using the sulfur iodine cycle will be performed under prototypic conditions to demonstrate the key chemical processes, to check the materials and to provide the technical basis for evaluating the S-I cycle for nuclear hydrogen production (process efficiency and preliminary costs). The S-I cycle has been split into three sections. Each must complete stand alone tests prior to closed loop operation. CEA is responsible for the development, construction and operation of the Bunsen section where hydro-iodic acid and sulfuric acid are generated. After a general description of the loop and its objectives, a focus is made on the section provided by CEA, its design and the first tests performed in stand-alone mode. Reflexions on a preliminary scale up of major components for an industrial unit are also discussed. (authors)

Leybros, Jean; Duhamet, Jean; Ode, Denis; Pons, Nicolas; Dehaudt, Philippe; Boidron, Michel [Commissariat a l'Energie Atomique DEN/VRH/DTEC BP17171 - Marcoule - 30207 BAGNOLS SUR CEZE Cedex (France); Helie, Max [Commissariat a l'Energie Atomique, DEN/DANS/DPC - Centre de Saclay - 91191 GIF-SUR YVETTE Cedex (France)

2007-07-01

249

Laboratory and clinical experience with neodymium:YAG laser prostatectomy  

NASA Astrophysics Data System (ADS)

Since 1991, we have undertaken extensive laboratory and clinical studies of the Neodymium:YAG (Nd:YAG) laser for surgical treatment of bladder outlet obstruction due to prostatic enlargement or benign prostatic hyperplasia (BPH). Side-firing optical fibers which emit a divergent, relatively low energy density Nd:YAG laser beam produce coagulation necrosis of obstructing periurethral prostate tissue, followed by gradual dissolution and slough in the urinary stream. Laser-tissue interactions and Nd:YAG laser dosimetry for prostatectomy have been studied in canine and human prostate model systems, enhancing clinical application. Ongoing studies examine comparative Nd:YAG laser dosimetry for various beam configurations produced by available side-firing optical fibers and continue to refine operative technique. We have documented clinical outcomes of Nd:YAG laser prostatectomy in 230 consecutive patients treated with the UrolaseTM side-firing optical fiber. Nd:YAG laser coagulation the prostate produces a remarkably low acute morbidity profile, with no significant bleeding or fluid absorption. No postoperative incontinence has been produced. Serial assessments of voiding outcomes over more than 3 years of followup show objective and symptomatic improvement following Nd:YAG laser prostatectomy which is comparable to older but more morbid electrosurgical approaches. Nd:YAG laser prostatectomy is a safe, efficacious, durable and cost-effective treatment for BPH.

Kabalin, John N.

1996-05-01

250

Subpicosecond compression experiments at Los Alamos National Laboratory  

SciTech Connect

The authors report on recent experiments using a magnetic chicane compressor at 8 MeV. Electron bunches at both low (0.1 nC) and high (1 nC) charges were compressed from 20 ps to less than 1 ps (FWHM). A transverse deflecting rf cavity was used to measure the bunch length at low charge; the bunch length at high charge was inferred from an induced energy spread of the beam. The longitudinal centrifugal-space charge force is calculated using a point-to-point numerical simulation and is shown not to influence the energy-spread measurement.

Carlsten, B.E.; Russell, S.J.; Kinross-Wright, J.M. [and others

1995-09-01

251

Courseware for ultrasonic medical diagnostics curriculum: system for on-site and remote laboratory experiments  

Microsoft Academic Search

The aim of this paper is to present the implementation approach of on-site and remote experimenting laboratory for ultrasound medical diagnostics curriculum. We demonstrate the implementation of such laboratory using virtual instrument that is built by using a standard computer, a ultrasonic transducer with a tissue like phantom, digitizer, function generator and the software package LabView. By controlling the virtual

R. Jurkonis; V. Marozas; A. Lukoševi?ius

2008-01-01

252

Solvent-Free Wittig Reaction: A Green Organic Chemistry Laboratory Experiment  

ERIC Educational Resources Information Center

Some Wittig reactions can be carried out by grinding the reactants in a mortar with a pestle for about 20 minutes, as per investigation. A laboratory experiment involving a solvent-free Wittig reaction that can be completed in a three-hour sophomore organic chemistry laboratory class period, are developed.

Leung, Sam H.; Angel, Stephen A.

2004-01-01

253

Real-Time Internet Mediated Laboratory Experiments for Distance Education Students.  

ERIC Educational Resources Information Center

Discusses the demand for distance education opportunities in engineering and science and considers delivery methods for theoretical content and for laboratory work. Explains the Real-Time Internet Mediated Laboratory Experiments (RTIMLE) that use the World Wide Web, and suggests that RTIMLE may be most appropriate for students who already have…

Lemckert, Charles; Florance, John

2002-01-01

254

Biomass burning smoke aerosol properties measured during Fire Laboratory at Missoula Experiments (FLAME)  

Microsoft Academic Search

During the Fire Laboratory at Missoula Experiments (FLAME), we studied the physical, chemical, and optical properties of biomass burning smoke from the laboratory combustion of various wildland fuels. A good understanding of these properties is important in determining the radiative effects of biomass burning aerosols, with impacts on both local and regional visibility and global climate. We measured aerosol size

E. J. T. Levin; G. R. McMeeking; C. M. Carrico; L. E. Mack; S. M. Kreidenweis; C. E. Wold; H. Moosmüller; W. P. Arnott; W. M. Hao; J. L. Collett Jr; W. C. Malm

2010-01-01

255

The Synthesis of a Cockroach Pheromone: An Experiment for the Second-Year Organic Chemistry Laboratory  

ERIC Educational Resources Information Center

This experiment describes the synthesis of gentisyl quinone isovalerate, or blattellaquinone, a sex pheromone of the German cockroach that was isolated and identified in 2005. The synthesis is appropriate for the second semester of a second-year organic chemistry laboratory course. It can be completed in two, three-hour laboratory periods and uses…

Feist, Patty L.

2008-01-01

256

Combustion and Energy Transfer Experiments: A Laboratory Model for Linking Core Concepts across the Science Curriculum  

ERIC Educational Resources Information Center

Core concepts can be integrated throughout lower-division science and engineering courses by using a series of related, cross-referenced laboratory experiments. Starting with butane combustion in chemistry, the authors expanded the underlying core concepts of energy transfer into laboratories designed for biology, physics, and engineering. This…

Barreto, Jose C.; Dubetz, Terry A.; Schmidt, Diane L.; Isern, Sharon; Beatty, Thomas; Brown, David W.; Gillman, Edward; Alberte, Randall S.; Egiebor, Nosa O.

2007-01-01

257

Laboratory experiments of heat and moisture fluxes through supraglacial debris  

NASA Astrophysics Data System (ADS)

Inspired by earlier work (Reznichenko et al., 2010), we have carried out experiments within a climate chamber to explore the best ways to measure the heat and moisture fluxes through supraglacial debris. Sample ice blocks were prepared with debris cover of varying lithology, grain size and thickness and were instrumented with a combination of Gemini TinyTag temperature/relative humidity sensors and Decagon soil moisture sensors in order to monitor the heat and moisture fluxes through the overlying debris material when the experiment is exposed to specified solar lamp radiation and laminar airflow within the temperature-controlled climate chamber. Experimental results can be used to determine the optimal set up for numerical models of heat and moisture flux through supraglacial debris and also indicate the performance limitations of such sensors that can be expected in field installations. Reznichenko, N., Davies, T., Shulmeister, J. and McSaveney, M. (2010) Effects of debris on ice-surface melting rates: an experimental study. Journal of Glaciology, Volume 56, Number 197, 384-394.

Nicholson, Lindsey; Mayer, Christoph; Wirbel, Anna

2014-05-01

258

How astronauts would conduct a seismic experiment on the planet Mars  

NASA Astrophysics Data System (ADS)

During the Summer 2001 Flashline Mars Arctic Research Station (M.A.R.S.) campaign in Devon Island, Nunavut, Canada, the crew of the second rotation conducted a geophysics experiment aiming at assessing the feasibility of an active seismology method to detect subsurface water on Mars. A crew of three deployed a line of 24 sensors. Reflected and refracted signals produced by mini-quakes generated by a sledge hammer were recorded by a seismograph. The experiment was conducted three times, once in a dry run and twice during simulated Extra-Vehicular Activities (EVA) on the edge of the Haughton crater, allowing a three dimensional characterization of the subsurface ground to a depth of several hundred meters. Data were recorded for later detailed processing. A third EVA attempt inside the crater had to be aborted because of the poor weather and terrain conditions. Despite this failed attempt, a large amount of results were collected. Several operational lessons were learned from conducting this experiment under simulated EVA conditions. This paper presents the experiment and the methodology used, reviews the experiment performance and summarizes the results obtained and the operational lessons learned.

Pletser, V.; Lognonne, P.; Dehant, V.

259

Laboratory: Undergraduate Laboratory Experiment Teaching Fundamental Concepts of Rheology in Context of Sickle Cell Anemia  

ERIC Educational Resources Information Center

This paper describes a biomedical engineering experiment that introduces students to rheology. Healthy and sickle-cell blood analogs are prepared that are composed of chitosan particles suspended in aqueous glycerol solutions, which substitute for RBCs and plasma, respectively. Students study flow properties of the blood analogs with a viscometer…

Vernengo, Jennifer; Purdy, Caitlin; Farrell, Stephanie

2014-01-01

260

Birmingham Urban Climate Laboratory (BUCL): Experiences, Challenges and Applications of an Urban Temperature Network  

NASA Astrophysics Data System (ADS)

The Birmingham Urban Climate Laboratory (BUCL) has recently been established by the University of Birmingham. BUCL is an in-situ, real-time urban network that will incorporate 3 nested networks - a wide-array of 25 weather stations, a dense array of 131 low-cost air temperature sensors and a fine-array of temperature sensor across the city-centre (50/km^2) - with the primary aim of monitoring air temperatures across a morphologically-heterogeneous urban conurbation for a variety of applications. During its installation there have been a number of challenges to overcome, including siting equipment in suitable urban locations, ensuring that the measurements were 'representative' of the local-scale climate, managing a large, near real-time data set and implementing QA/QC procedures. From these experiences, the establishment of a standardised urban meteorological network metadata protocol has been proposed in order to improve data quality, to ensure the end-user has access to all the supplementary information they would require for conducting valid analyses and to encourage the adequate recording and documentation of any changes to in-situ urban networks over time. This paper will provide an introduction to the BUCL in-situ network, give an overview of the challenges and experiences gained from its implementation, and finally discuss the proposed applications of the network, including its use in remote sensing observations of urban temperatures, as well as health and infrastructure applications.

Muller, Catherine; Chapman, Lee; Young, Duick; Grimmond, Sue; Cai, Xiaoming

2013-04-01

261

A laboratory experiment assessing the effect of sea ice on wave dumping  

NASA Astrophysics Data System (ADS)

Wave-ice interaction is a critical factor in the dynamics of the marginal ice zone (MIZ), the region between open ocean and an expanse of ice floes of varying size and shape. This interaction works both ways: while waves cause the fractures of ice floes, the presence of ice floes affects waves through scattering and various dissipative processes. In order to assess the latter, a laboratory experiment has been carried out in the coastal directional basin at Plymouth University. Sea ice has been simulated with two deformable plates: 1mX1m plastic sheet with variable thickness of polypropylene, which holds the same density (~0.9 g/cm3) of ice, and PVC Forex, which hold the same mechanical property of ice. Experiments have been conducted using monochromatic as well as random wave fields with different steepness and wavelengths (both shorter and larger than the floe). The wave field has been monitored before and after the simulated ice floe with a number of wave probes deployed along the basin, including a 6-probe array to track directional properties. On the whole, results show a substantial scattering and dissipation of the wave field, which appears to be dependent on the amount of overwash on the ice floe.

Cavaliere, Claudio; Alberello, Alberto; Bennetts, Luke; Meylan, Mike; Babanin, Alexander; Malavasi, Stefano; Toffoli, Alessandro

2014-05-01

262

Subpicosecond Compression Experiments at Los Alamos National Laboratory  

SciTech Connect

We report on recent experiments using a magnetic chicane compressor at 8 MeV. Electron bunches at both low (0.1 nC) and high (1 nC) charges were compressed from 10{endash}15 ps to less than 1 ps (FWHM). A transverse deflecting rf cavity was used to measure the bunch length at low charge; the bunch length at high charge was inferred from the induced energy spread of the beam. The longitudinal centrifugal space-charge force [{ital Phys}. {ital Rev}. {ital E} {bold 51}, 1453 (1995)] is calculated using a point-to-point numerical simulation and is shown not to influence the energy-spread measurement. {copyright} {ital 1996 American Institute of Physics.}

Carlsten, B.E.; Feldman, D.W.; Kinross-Wright, J.M.; Milder, M.L.; Russell, S.J.; Plato, J.G.; Sherwood, B.A.; Weber, M.E.; Cooper, R.G.; Sturges, R.E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

1996-04-01

263

Laboratory evaluation of the constant rate of strain and constant head techniques for measurement of the hydraulic conductivity of fine grained soils  

E-print Network

This thesis evaluates the constant rate of strain and constant head techniques for measurement of the hydraulic conductivity of fine grained soils. A laboratory program compares hydraulic conductivity measurements made ...

Adams, Amy Lynn

2011-01-01

264

Onset of perched water in a gradually layered soil: a laboratory experiment  

NASA Astrophysics Data System (ADS)

The genetic layering of the soil hydrological properties can significanly affect a number of processes as the onset of soil-slips, the runoff production and those related to the interaction between soil, water, plants and atmosphere. Therefore, with the aim of better understanding some aspects of these processes, we focused on the effect, during an imbibition process, of the decrease of the soil hydraulic conductivity at saturation Ks. A laboratory experiment was setup in order to observe the conditions and dynamics of the onset of a perched water in a gradually layered soil. A prismatic column was realised and filled with 9 different soil strata, each 0.1 m deep, whose grain-size distribution curve and porosity were such as to reproduce an exponential decay of Ks, on the basis of the application of a modified Kozeny-Carman relatioship. The so-rebuilt soil was artificially wetted by means of a rainfall simulator at a rate previously determined in order to maintain a constant water content on the surface for 9 hours. Istantaneous volumetric water content profiles were measured along the soil profile by means of 9 TDR probes and a multiplexer device. As a result of the experiment we observed and documented the formation of a water content peak at about 0.15 m depth, about 1.5 h after the beginning of the imbibition process. Then the peak emphasised and moved downward and a perched water formed at an intermediate height in the column, about 6 h after the beginning of the experiment. By this experiment we could then verify the formation of a water content peak, as predicted by a previously developed theoretical model and by a finite volume numerical simulation. The peak is then enveloped reaching the saturation as the wetting front moves downward. The perched water depth then rapidly increased upward while the wetting front slowly travelled downward. Before the transition toward saturation, the experiment supported the phoenomenological aspects enlightened by the analytical solution, although the adopted Gardner's constitutive laws tend to overestimate the unsaturated conductivity for most of the soils. A quantitative good agreement was observed between the experimental data and the numerical simulations.

Barontini, S.; Belluardo, G.; Bacchi, B.; Ranzi, R.

2009-04-01

265

Surface Conductive Glass.  

ERIC Educational Resources Information Center

Discusses the properties of surface-conducting glass and the chemical nature of surface-conducting stannic (tin) oxide. Also provides the procedures necessary for the preparation of surface-conducting stannic oxide films on glass substrates. The experiment is suitable for the advanced inorganic chemistry laboratory. (JN)

Tanaka, John; Suib, Steven L.

1984-01-01

266

Effect of ionic ordering in conductivity experiments of DNA aqueous solutions  

E-print Network

The effects of ionic ordering in DNA water solutions are studied by conductivity experiments. The conductivity measurements are performed for the solutions of DNA with KCl salt in the temperature range from 28 to 70 C. Salt concentration vary from 0 to 2 M. The conductivity of solutions without DNA but with the same concentration of KCl salt are also performed. The results show that in case of salt free solution of DNA the melting process of the double helix is observed, while in case of DNA solution with added salt the macromolecule denaturation is not featured. For salt concentrations lower than some critical one (0.4 M) the conductivity of DNA solution is higher than the conductivity of KCl water solution without DNA. Starting from the critical concentration the conductivity of KCl solution is higher than the conductivity of DNA solution with added salt. For description of the experimental data phenomenological model is elaborated basing on electrolyte theory. In framework of the developed model a mechanis...

Liubysh, O O; Tkachov, S Yu; Perepelytsya, S M

2014-01-01

267

Laboratory experiments on active suppression of advanced turboprop noise  

NASA Astrophysics Data System (ADS)

The noise generated by supersonic tip speed propellers may be a cabin environment problem for future propeller-driven airplanes. Active suppression from speakers inside the airplane cabin has been proposed for canceling out this noise. The potential of active suppression of advanced turboprop noise was tested by using speakers in a rectangular duct. Experiments were first performed with sine wave signals. The results compared well with the ideal cancellation curve of noise as a function of phase angle. Recorded noise signals from subsonic and supersonic tip speed propellers were than used in the duct to deterthe potential for canceling their noise. The subsonic propeller data showed significant cancellations but less than those obtained with the sine wave. The blade-passing-tone cancellation curve for the supersonic propeller was very similar to the subsonic curve, indicating that it is potentially just as easy to cancel supersonic as subsonic propeller blade-passing-tone noise. Propeller duct data from a recorded propeller source and spatial data taken on a propeller-drive airplane showed generally good agreement when compared versus phase angle. This agreement, combined with the similarity of the subsonic and supersonic duct propeller data, indicates that the area of cancellation for advanced supersonic propellers will be similar to that measured on the airplane. Since the area of cancellation on the airplane was small, a method for improving the active noise suppression by using outside speakers is discussed.

Dittmar, J. H.

1985-12-01

268

Phosphatidylcholine from "Healthful" Egg Yolk Varieties: An Organic Laboratory Experience  

NASA Astrophysics Data System (ADS)

I have added an investigative element to a popular undergraduate experiment. the characterization of phosphatidylcholine (PC) from egg yolks. Varieties of eggs are commercially available which have been obtained from chickens fed a diet containing no animal fat. Presumably, less saturated fat in the diet of the chickens could be reflected in the fatty acid composition of various classes of biological lipids, including phospholipids, in the eggs from these chickens. PC is extracted using conventional methods, the extract is further purified by chromatography on silicic acid, and the column fractions are assayed for the presence and purity of PC by TLC. Fractions containing pure PC are pooled, concentrated, hydrolyzed, and esterified to obtain the fatty acid methyl esters (FAME) which are identified by GLC. Comparing FAMEs derived from PC of yolks of regular eggs to those obtained from the other special brands adds a novel twist to the students' work and generates greater student interest and involvement in both the interpretation of data than a simple isolation of a biological compound alone evokes.

Hodges, Linda C.

1995-12-01

269

[The experiments with laboratory animals from a bioethical point of view--history, modern time, perspectives].  

PubMed

The origin of laboratory animal science was called forth by violent development of experimental biology and medicine in the XIX century on the one hand, and on the other hand by the necessity to have standard healthy animals for experiments with strictly definite biological characteristics. With this aim in view management technology and animal use in experiments have been constantly improved. "Laboratory animal" notion has been formed by the end of the XIX century. At the beginning of laboratory animal science development ethical problems were not as urgent as they are now. It is established that the three Rs bioethical conception of W.M.S. Russel and R.L. Burch (1959) has influence on modern state and perspectives of the development of animal experimental methods. It is shown that the existence of laboratory animal protection laws and the reflection in them of compulsory ethical review of scientific project and statistics of used laboratory animals is absolutely necessary. PMID:15174298

Kopaladze, R A

2004-01-01

270

Ground-Laboratory to In-Space Atomic Oxygen Correlation for the Polymer Erosion and Contamination Experiment (PEACE) Polymers  

NASA Technical Reports Server (NTRS)

The Materials International Space Station Experiment 2 (MISSE 2) Polymer Erosion and Contamination Experiment (PEACE) polymers were exposed to the environment of low Earth orbit (LEO) for 3.95 years from 2001 to 2005. There were 41 different PEACE polymers, which were flown on the exterior of the International Space Station (ISS) in order to determine their atomic oxygen erosion yields. In LEO, atomic oxygen is an environmental durability threat, particularly for long duration mission exposures. Although spaceflight experiments, such as the MISSE 2 PEACE experiment, are ideal for determining LEO environmental durability of spacecraft materials, ground-laboratory testing is often relied upon for durability evaluation and prediction. Unfortunately, significant differences exist between LEO atomic oxygen exposure and atomic oxygen exposure in ground-laboratory facilities. These differences include variations in species, energies, thermal exposures and radiation exposures, all of which may result in different reactions and erosion rates. In an effort to improve the accuracy of ground-based durability testing, ground-laboratory to in-space atomic oxygen correlation experiments have been conducted. In these tests, the atomic oxygen erosion yields of the PEACE polymers were determined relative to Kapton H using a radio-frequency (RF) plasma asher (operated on air). The asher erosion yields were compared to the MISSE 2 PEACE erosion yields to determine the correlation between erosion rates in the two environments. This paper provides a summary of the MISSE 2 PEACE experiment; it reviews the specific polymers tested as well as the techniques used to determine erosion yield in the asher, and it provides a correlation between the space and ground laboratory erosion yield values. Using the PEACE polymers asher to in-space erosion yield ratios will allow more accurate in-space materials performance predictions to be made based on plasma asher durability evaluation.

Stambler, Arielle H.; Inoshita, Karen E.; Roberts, Lily M.; Barbagallo, Claire E.; deGroh, Kim K.; Banks, Bruce A.

2011-01-01

271

Undergraduates at Sea and in the Laboratory Conducting Habitat Mapping Using Multibeam and Sidescan Sonar  

NASA Astrophysics Data System (ADS)

During the last five years, undergraduate students at the College of Charleston have had numerous opportunities to take part in the college's Transect Program and sail aboard research vessels on 2-5 day cruises to study the continental shelf. The program's purpose is to train students in oceanographic research while developing a long-term information geodatabase to characterize and monitor essential fish habitats, and to map seafloor geomorphology. During these cruises students take the lead to conduct a variety of research investigations which include hydrographic surveys of the seafloor using sidescan sonar, multibeam bathymetry, and video collected using a remotely operated vehicle and during SCUBA dives. Following the data collection cruises, students have enrolled in semester-long research courses to analyze data and document results through poster and oral presentations. More than 60 students have taken part in at least one of 6 programs. In the past two years, the NOAA Ship NANCY FOSTER has provided invaluable sea time to conduct multibeam surveys of the mid- and outer continental shelf off Charleston, so that the 22 participating Transect students have focused their work on seafloor mapping, and have become trained in state-of-the art CARIS multibeam and sidescan sonar processing software. Most of these students have presented their results at professional meetings, and manuscripts are currently in preparation. Students have had numerous post-program opportunities to conduct further research at sea and in the lab. They have collaborated with NOAA scientists and other investigators, conducting bathymetry data processing and analysis from other regions. Most recently, two program graduates worked with University of Washington investigators to map sites for the Ocean Observatory Initiative Regional Scale Nodes. Several students have been contracted or hired as hydrographic survey technicians, while others have gone to graduate school to continue their work using these invaluable skills learned as undergraduates.

Sautter, L. R.; Harris, M. S.

2008-12-01

272

Computational/experimental basis for conducting alkane droplet combustion experiments on space-based-platforms  

NASA Technical Reports Server (NTRS)

An analysis is conducted of the requirement for the conduct of spherically symmetric droplet-combustion experiments on space platforms, on the basis of a novel time-dependent computational droplet combustion model that allows the time- and temperature-dependent transport characteristics to be incorporated. While at low oxygen indices the droplet burning extinction becomes a strong function of oxygen index, it becomes a weaker function at higher oxygen index values. The oxygen index that separates these two ranges are dependent on the diluent, being higher for He and lower for N.

Choi, Mun Y.; Cho, Seog Y.; Dryer, Frederick L.; Haggard, John B., Jr.

1992-01-01

273

Sediment-contact and survival of fingernail clams: Implications for conducting short-term laboratory tests  

USGS Publications Warehouse

Porewater toxicity tests have been used as indicators of whole sediment toxicity. However, many species commonly tested in porewater predominately reside in the water column and otherwise have little to no direct contact with sediment and associated porewater. We assessed the feasibility of porewater toxicity tests with fingernail clams Musculium transversum, a benthic macroinvertebrate that inhabits soft bottom sediments and feeds by filtering surface and porewater. Fingernail clams were exposed to water or sediment in a 96 h laboratory test with a 5 x 2 factorial experimental design. The five treatments included sediments from four sites in the Mississippi River and one sediment-free control (well water). In all treatments, clams were exposed to the sediments or water either directly (no enclosure) or indirectly (enclosure, suspended above the sediment surface). There were three replicates for each of the ten treatment combinations. Overall, survival of fingernail clams did not vary among the five treatments (p = 0.36). In treatments without enclosures, survival of clams in the sediment-free control was not significantly different (p = 0.34) from the sediment-containing treatments. Survival of clams in the sediment-free control averaged 85 - suggesting that direct sediment contact is not necessary for survival in short-term tests. In contrast, survival of clams in the sediment-containing treatments differed significantly (p = 0.03) between exposures with (mean, 77) and without (mean, 89) enclosures. Thus, fingernail clams may provide an alternative species for evaluating benthic macroinvertebrates in short-term laboratory porewater tests. However, more information on their physiological requirements and the development of sublethal endpoints is recommended before their use in tests of longer duration. (C) 2000 by John Wiley and Sons, Inc.

Naimo, T.J.; Cope, W.G.; Bartsch, M.R.

2000-01-01

274

Bacterial Etiologies of Five Core Syndromes: Laboratory-Based Syndromic Surveillance Conducted in Guangxi, China  

PubMed Central

Background Under the existing national surveillance system in China for selected infectious diseases, bacterial cultures are performed for only a small percentage of reported cases. We set up a laboratory-based syndromic surveillance system to elucidate bacterial etiologic spectrum and detect infection by rare etiologies (or serogroups) for five core syndromes in the given study area. Methods Patients presenting with one of five core syndromes at nine sentinel hospitals in Guagnxi, China were evaluated using laboratory-based syndrome surveillance to elucidate bacterial etiologies. We collected respiratory and stool specimens, as well as CSF, blood and other related samples for bacterial cultures and pulse field gel electrophoresis (PFGE) assays. Results From February 2009 to December 2011, 2,964 patients were enrolled in the study. Etiologies were identified in 320 (10.08%) patients. Streptococcus pneumonia (37 strains, 24.18%), Klebsiella pneumonia (34, 22.22%), Pseudomonas aeruginosa (19, 12.42%) and Haemophilus influenza (18, 11.76%) were the most frequent pathogens for fever and respiratory syndrome, while Salmonella (77, 81.05%) was most often seen in diarrhea syndrome cases. Salmonella paratyphi A (38, 86.36%) occurred in fever and rash syndrome, with Cryptococcus neoformans (20, 35.09%), Streptococcus pneumonia (5, 8.77%), Klebsiella pneumonia (5, 8.77%),streptococcus suis (3, 5.26%) and Neisseria meningitides group B (2, 3.51%) being the most frequently detected in encephalitis-meningitis syndrome. To date no pathogen was isolated from the specimens from fever and hemorrhage patients. Conclusions In addition to common bacterial pathogens, opportunistic pathogens and fungal infections require more attention. Our study contributes to the strengthening of the existing national surveillance system and provides references for other regions that are similar to the study area. PMID:25360596

Dong, Baiqing; Liang, Dabin; Lin, Mei; Wang, Mingliu; Zeng, Jun; Liao, Hezhuang; Zhou, Lingyun; Huang, Jun; Wei, Xiaolin; Zou, Guanyang; Jing, Huaiqi

2014-01-01

275

Oil Formation: An "Unexpected" Difficulty in an Elementary Organic Laboratory Experiment  

ERIC Educational Resources Information Center

Describes an undergraduate organic laboratory experiment involving the separation of an unknown solid organic acid and an unknown solid organic base. The experiment is designed to present the student with an unexpected difficulty, namely, the formation of a separable viscous liquid, to see how the student handles this difficulty. (MLH)

Lewis, Dennis A.

1975-01-01

276

Size Exclusion Chromatography: An Experiment for High School and Community College Chemistry and Biotechnology Laboratory Programs  

ERIC Educational Resources Information Center

A simple multiday laboratory exercise suitable for use in a high school or community college chemistry course or a biotechnology advanced placement biology course is described. In this experiment students gain experience in the use of column chromatography as a tool for the separation and characterization of biomolecules, thus expanding their…

Brunauer, Linda S.; Davis, Kathryn K.

2008-01-01

277

Cross-Disciplinary Thermoregulation and Sweat Analysis Laboratory Experiences for Undergraduate Chemistry and Exercise Science Students  

ERIC Educational Resources Information Center

Cross-disciplinary (CD) learning experiences benefit student understanding of concepts and curriculum by offering opportunities to explore topics from the perspectives of alternate fields of study. This report involves a qualitative evaluation of CD health sciences undergraduate laboratory experiences in which concepts and students from two…

Mulligan, Gregory; Taylor, Nichole; Glen, Mary; Tomlin, Dona; Gaul, Catherine A.

2011-01-01

278

Topics in Chemical Instrumentation: XCVIII. Experiments Involving Thermal Methods of Analysis for Undergraduate Chemistry Laboratories.  

ERIC Educational Resources Information Center

Explains some experiments involving thermal methods of analysis for undergraduate chemistry laboratories. Some experiments are: (1) the determination of the density and degree of crystallinity of a polymer; and (2) the determination of the specific heat of a nonvolatile compound. (HM)

Ewing, Galen W., Ed.

1978-01-01

279

Dark matter searches with NaI scintillators in the Canfranc underground laboratory: ANAIS experiment  

NASA Astrophysics Data System (ADS)

A large mass dark matter search experiment with NaI scintillators at the Canfranc Underground Laboratory is underway. A 10.7 kg prototype with improved light collection efficiency and special low-background improvements has been tested and started taking data underground in summer 2005. Preliminary results and prospects for the experiment are presented.

Amaré, J.; Beltrán, B.; Carmona, J. M.; Cebrián, S.; García, E.; Gómez, H.; Irastorza, I. G.; Luzón, G.; Martínez, M.; Morales, J.; Ortiz de Solórzano, A.; Pobes, C.; Puimedón, J.; Rodríguez, A.; Ruz, J.; Sarsa, M. L.; Torres, L.; Villar, J. A.

2006-05-01

280

Laboratory Experiments on the Electrochemical Remediation of the Environment. Part 8. Microscale Simultaneous Photocatalysis  

ERIC Educational Resources Information Center

A microscale experiment in which the simultaneous oxidation of an organic compound and the reduction of a metal ion are photocatalytically performed in an aqueous slurry containing TiO[subscript 2] irradiated with UV light. This experiment can be performed in the laboratory session with simple chemicals and equipments.

Ibanez, Jorge G.; Mena-Brito, Rodrigo; Fregoso-Infante, Arturo

2005-01-01

281

Lysozyme Thermal Denaturation and Self-Interaction: Four Integrated Thermodynamic Experiments for the Physical Chemistry Laboratory  

ERIC Educational Resources Information Center

As part of an effort to infuse our physical chemistry laboratory with biologically relevant, investigative experiments, we detail four integrated thermodynamic experiments that characterize the denaturation (or unfolding) and self-interaction of hen egg white lysozyme as a function of pH and ionic strength. Students first use Protein Explorer to…

Schwinefus, Jeffrey J.; Schaefle, Nathaniel J.; Muth, Gregory W.; Miessler, Gary L.; Clark, Christopher A.

2008-01-01

282

An Enzymatic Clinical Chemistry Laboratory Experiment Incorporating an Introduction to Mathematical Method Comparison Techniques  

ERIC Educational Resources Information Center

An enzymatic laboratory experiment based on the analysis of serum is described that is suitable for students of clinical chemistry. The experiment incorporates an introduction to mathematical method-comparison techniques in which three different clinical glucose analysis methods are compared using linear regression and Bland-Altman difference…

Duxbury, Mark

2004-01-01

283

Prospective Teachers' Perceptions of the Value of an Early Field Experience in a Laboratory Setting  

ERIC Educational Resources Information Center

Because there is limited research on effective early field experiences and, particularly, on the potential of laboratory experiences to expose teacher candidates to a diverse student population, this study evaluates one such placement. As part of the placement, the teacher candidate provided tutoring at an on-campus model alternative program for…

Wasburn-Moses, Leah; Kopp, Tom; Hettersimer, Jill E.

2012-01-01

284

The Equilibrium Constant for Bromothymol Blue: A General Chemistry Laboratory Experiment Using Spectroscopy  

ERIC Educational Resources Information Center

A simple, inexpensive, and environmentally friendly undergraduate laboratory experiment is described in which students use visible spectroscopy to determine a numerical value for an equilibrium constant, K[subscript c]. The experiment correlates well with the lecture topic of equilibrium even though the subject of the study is an acid-base…

Klotz, Elsbeth; Doyle, Robert; Gross, Erin; Mattson, Bruce

2011-01-01

285

DENSE MATTER IN LASER DRIVEN FUSION ! LABORATORY EXPERIMENTS R.L. Mc Crory and J. Wilson  

E-print Network

a survey of laser plasma Interaction experiments cur- rently in progress at the Laboratory for Laser, it is hopped that this brief summary of capabilities will stimulate interaction investigations into high energy density interaction experiments made possible by the presently available high power lasers. In particular

Boyer, Edmond

286

Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory  

ERIC Educational Resources Information Center

We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

2008-01-01

287

An Investigation of Students' Prior Experience with Laboratory Practicals and Report-Writing.  

ERIC Educational Resources Information Center

A study of 723 University of Cape Town (South Africa) physics students investigated their prior experience with laboratory procedures and technical report writing. Results suggest that, although students are generally aware of the importance of these elements of learning, school experience with teaching of scientific concepts and skills is often…

Kaunda, L.; Ball, D.

1998-01-01

288

[Collaboration between science and practice: experiences of conducting a nursing intervention study].  

PubMed

In a five-year intervention study about the impact of pre-operative mobilisation training session of patients receiving an elective medial laparotomy experiences about the collaboration between practice (University Hospital Ulm) and science (Hessian Institute of Nursing Research) were made. During the project possibilities and borders of clinical nursing research became clear. A research question based on practice experiences of nurses helps to develop and maintain motivation to conduct a study at a nursing unit. There was a lack of nursing knowledge to develop the best possible design, e.g. outcome criteria for mobilisation and standardized assessment instruments. The cooperation with other health care professionals (human movement science, statistics) was important and without difficulties. In Germany, without doctors' agreement and common application it is impossible to conduct nursing intervention studies in hospitals. It is necessary to train nursing specialists with both scientific and clinical competence to explore systematically clinical research questions. PMID:19750976

Panfil, Eva-Maria; Kirchner, Elisabeth; Bauder-Missbach, Heidi; Haasenritter, Jörg; Eisenschink, Anna Maria

2009-09-01

289

Plasma physics and environmental perturbation laboratory. [magnetospheric experiments from space shuttle  

NASA Technical Reports Server (NTRS)

Current work aimed at identifying the active magnetospheric experiments that can be performed from the Space Shuttle, and designing a laboratory to carry out these experiments is described. The laboratory, known as the PPEPL (Plasma Physics and Environmental Perturbation Laboratory) consists of 35-ft pallet of instruments connected to a 25-ft pressurized control module. The systems deployed from the pallet are two 50-m booms, two subsatellites, a high-power transmitter, a multipurpose accelerator, a set of deployable canisters, and a gimbaled instrument platform. Missions are planned to last seven days, during which two scientists will carry out experiments from within the pressurized module. The type of experiments to be performed are outlined.

Vogl, J. L.

1973-01-01

290

Laboratory Experiments to Study Plasma Jet and Shock Using High-Power Lasers  

Microsoft Academic Search

We describe laboratory laser-plasma experiments to form plasma jets and study jet driven shocks. Particular questions that are of interest are the formation and collimation of these jets, the relevance of experiment to astrophysical jets, and the formation of collisionless shock waves. The experiments were performed with Gekko XII HIPER laser system (3w, 500 ps, ˜10^15 W\\/cm^2) at the Institute

Youichi Sakawa; S. Dono; Y. Kuramitsu; T. Kato; T. Kimura; K. Miyanishi; T. Endo; N. Ozaki; H. Nagatomo; K. Shigemori; R. Kodama; T. Norimatsu; H. Takabe; J. Waugh; N. Woolsey; B. Loupias; M. Koenig

2008-01-01

291

Laboratory experiments on the effectiveness of straw mulch on soil degradation processes under simulated rainfall  

NASA Astrophysics Data System (ADS)

Several relevant hydrological processes (e.g. runoff, sediment transport, soil moisture) were investigated in laboratory to evaluate the effectiveness of distinct rice straw mulching densities on reducing soil degradation and conserving soil water. Mulching cover has been used as a common management practice to improve water use efficiency and soil conservation in agricultural lands of semiarid regions characterized by irregular storm patterns with intense and short rainfall events. Soil degradation and nutrient losses are a main threat for agricultural lands, reducing soil fertility, land productivity and eventually leading to the unsustainability of agricultural production systems. Laboratory experiments were conducted using a free drainage rectangular soil flume (3.0 × 0.3 m2) with a sandy loam soil from the right bank of Mondego River, in Coimbra (Portugal) and three soil surface conditions: 1) bare soil; 2) low mulching cover with 2 ton/ha density; and 3) high mulching cover with 4 ton/ha density. A steady single downward-oriented full-cone nozzle was used to simulate several rainfall events with different intensities and patterns in an intermittent way. A set of infrared bulbs placed above the soil flume were used to enhance evaporation between two successive rainfall events. The results clearly show that rice straw mulching and the characteristics of the rainfall events strongly affected infiltration, surface runoff and erosion. High mulching cover condition stabilized soil temperature better than the bare soil condition and increased significantly soil moisture. Mulching has conferred protection to the superficial layer of the soil, reducing the formation of rills and the transport of sediments, leading to the reduction of the degradation processes.

Abrantes, João; Montenegro, Abelardo; de Lima, João

2013-04-01

292

Change in student conceptual and technological knowledge as a result of the general chemistry laboratory experience  

NASA Astrophysics Data System (ADS)

The use of technology is continually changing within the field of chemistry and is increasingly being incorporated into teaching laboratories under the supposition that technology makes concepts more understandable. General chemistry students at South Dakota State University use computer-based laboratory technology weekly during data collection, analysis, and final submission of their laboratory reports. The purpose of this study was to assess the impact of technology on student learning. Qualitative and quantitative methods were used to analyze this impact. Surveys, observations, and interviews were used to collect data as students completed experiments during the general chemistry laboratory. Chi-square analysis determined that changes between pre- and post-survey data were statistically significant. A qualitative index (q) was used to assess which laboratory experiments had smaller or larger changes in student knowledge. Evidence of positive and negative changes in student conceptual and technological knowledge will be coupled to the various laboratory technology used by general chemistry laboratory students, including the Chem 2000, thermocouples, and the pH electrode. Data show that students initially were focused on learning the technology and that students re-directed their focus to learning laboratory concepts as the academic year progressed. Data show that the level of engagement students were at and their use of the visuals provided by the laboratory technology affected their learning. Data show that students emphasized collecting accurate and precise data in the laboratory and associated the technology with providing them with accurate and precise data. Data also shows the relationship between the lecture and laboratory portions of the general chemistry courses has no impact on student learning. Evidence of these impacts on student learning will be presented.

Williams, Marla F.

293

FEANICS: A Multi-User Facility For Conducting Solid Fuel Combustion Experiments On ISS  

NASA Technical Reports Server (NTRS)

The Destiny Module on the International Space Station (ISS) will soon be home for the Fluids and Combustion Facility's (FCF) Combustion Integrated Rack (CIR), which is being developed at the NASA Glenn Research Center in Cleveland, Ohio. The CIR will be the platform for future microgravity combustion experiments. A multi-user mini-facility called FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) will also be built at NASA Glenn. This mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct basic and applied scientific investigations in fire-safety to support NASA's Bioastronautics Initiative. The FEANICS project team will work in conjunction with the CIR project team to develop upgradeable and reusable hardware to meet the science requirements of current and future investigators. Currently, there are six experiments that are candidates to use the FEANICS mini-facility. This paper will describe the capabilities of this mini-facility and the type of solid combustion testing and diagnostics that can be performed.

Frate, David T.; Tofil, Todd A.

2001-01-01

294

Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000.  

PubMed

The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. PMID:12578007

Porterfield, D M; Neichitailo, G S; Mashinski, A L; Musgrave, M E

2003-01-01

295

Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000  

NASA Technical Reports Server (NTRS)

The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Porterfield, D. M.; Neichitailo, G. S.; Mashinski, A. L.; Musgrave, M. E.

2003-01-01

296

THE IPOS FRAMEWORK: LINKING FISH SWIMMING PERFORMANCE IN ALTERED FLOWS FROM LABORATORY EXPERIMENTS TO RIVERS  

SciTech Connect

Current understanding of the effects of turbulence on the swimming performance of fish 32 is primarily derived from laboratory experiments under pressurized flow swim tunnels 33 and open channel flow facilities. These studies have produced valuable information on 34 the swimming mechanics and behavior of fish in turbulent flow. However, laboratory 35 studies have limited representation of the flows fish experience in nature. The complex 36 flow structure in rivers is imparted primarily by the highly heterogeneous and non37 uniform bed and planform geometry. Our goal is to direct future laboratory and field 38 studies to adopt a common framework that will shape the integration of both approaches. 39 This paper outlines four characteristics of turbulent flow, which we suggest should be 40 evaluated when generalizing results from fish turbulent studies in both the laboratory and 41 the field. The framework is based on four turbulence characteristics that are summarized 42 under the acronym IPOS: Intensity, Periodicity, Orientation, and Scale.

Neary, Vincent S [ORNL

2011-01-01

297

Zero-gravity cloud physics laboratory: Candidate experiments definition and preliminary concept studies  

NASA Technical Reports Server (NTRS)

The candidate definition studies on the zero-g cloud physics laboratory are covered. This laboratory will be an independent self-contained shuttle sortie payload. Several critical technology areas have been identified and studied to assure proper consideration in terms of engineering requirements for the final design. Areas include chambers, gas and particle generators, environmental controls, motion controls, change controls, observational techniques, and composition controls. This unique laboratory will allow studies to be performed without mechanical, aerodynamics, electrical, or other type techniques to support the object under study. This report also covers the candidate experiment definitions, chambers and experiment classes, laboratory concepts and plans, special supporting studies, early flight opportunities and payload planning data for overall shuttle payload requirements assessments.

Eaton, L. R.; Greco, R. V.; Hollinden, A. B.

1973-01-01

298

Dynamics of Soil Water Evaporation during Soil Drying: Laboratory Experiment and Numerical Analysis  

PubMed Central

Laboratory and numerical experiments were conducted to investigate the evolution of soil water evaporation during a continuous drying event. Simulated soil water contents and temperatures by the calibrated model well reproduced measured values at different depths. Results show that the evaporative drying process could be divided into three stages, beginning with a relatively high evaporation rate during stage 1, followed by a lower rate during transient stage and stage 2, and finally maintaining a very low and constant rate during stage 3. The condensation zone was located immediately below the evaporation zone in the profile. Both peaks of evaporation and condensation rate increased rapidly during stage 1 and transition stage, decreased during stage 2, and maintained constant during stage 3. The width of evaporation zone kept a continuous increase during stages 1 and 2 and maintained a nearly constant value of 0.68?cm during stage 3. When the evaporation zone totally moved into the subsurface, a dry surface layer (DSL) formed above the evaporation zone at the end of stage 2. The width of DSL also presented a continuous increase during stage 2 and kept a constant value of 0.71?cm during stage 3. PMID:24489492

Han, Jiangbo; Zhou, Zhifang

2013-01-01

299

CUTANEOUS MANIFESTATIONS OF DEEP MYCOSIS: AN EXPERIENCE IN A TROPICAL PATHOLOGY LABORATORY  

PubMed Central

Background: Cutaneous manifestations of deep mycotic infection are fraught with delayed or misdiagnosis from mainly cutaneous neoplastic lesions. Aim: This study is designed to present our experience of these mycoses in a pathology laboratory in the tropics. Materials and Methods: A clinicopathologic analysis of deep mycotic infections was conducted over a 15 years period Formalin fixed and paraffin wax processed biopsies were stained with hematoxylin and eosin, periodic acid Schiff (PAS), and Grocott's methenamine silver (GMS) for the identification of fungus specie. Patients’ bio-data and clinical information were obtained from records. Results: Twenty males and seven females presented with 6 months to 6 years histories of varying symptoms of slow growing facial swellings, nodules, subcutaneous frontal skull swelling, proptosis, nasal blockage, epistaxis, discharging leg sinuses, flank mass, convulsion and pain. Of the 27 patients, four gave antecedent history of trauma, two had recurrent lesions which necessitated maxilectomy, two presented with convulsion without motor dysfunction while one had associated erosion of the small bones of the foot. None of the patients had debilitating illnesses such as diabetes mellitus, tuberculosis, and HIV infection. Tissue histology revealed histoplasmosis (10), mycetoma (9), subcutaneous phycomycosis (6), and phaeohyphomycosis (2). Conclusion: Deep mycoses may present primarily as cutaneous lesions in immunocompetent persons and often elicit distinct histologic inflammatory response characterized by granuloma formation. Diagnosis in resource constraint setting can be achieved with tissue stained with PAS and GMS which identifies implicated fungus. Clinical recognition and adequate knowledge of the pathology of these mycoses may reduce attendant patient morbidity. PMID:21772588

Samaila, Modupeola Omotara; Abdullahi, Kabiru

2011-01-01

300

Numerical and laboratory experiments on the dynamics of plume-ridge interaction. Progress report  

SciTech Connect

Mantle plumes and passive upwelling beneath ridges are the two dominant modes of mantle transport and thermal/chemical fluxing between the Earth`s deep interior and surface. While plumes and ridges independently contribute to crustal accretion, they also interact and the dispersion of plumes within the upper mantle is strongly modulated by mid-ocean ridges. The simplest mode of interaction, with the plume centered on the ridge, has been well documented and modeled. The remaining question is how plumes and ridges interact when the plume is located off-axis; it has been suggested that a pipeline-like flow from the off-axis plume to the ridge axis at the base of the rigid lithosphere may develop. Mid-ocean ridges migrating away from hot mantle plumes can be affected by plume discharges over long times and ridge migration distances. Salient feature of this model is that off-axis plumes communicate with the ridge through a channel resulting from the refraction and dispersion of an axi-symmetric plume conduit along the base of the sloping lithosphere. To test the dynamics of this model, a series of numerical and laboratory dynamic experiments on the problem of a fixed ridge and an off-axis buoyant upwelling were conducted. Results are discussed.

Kincaid, C. [Rhode Island Univ., Kingston, RI (United States). Graduate School of Oceanography; Gable, C.W. [Los Alamos National Lab., NM (United States)

1995-09-01

301

Experience of implementing ISO 17025 for the accreditation of a university testing laboratory  

Microsoft Academic Search

The experience of implementing a quality system on ISO 17025, and the accreditation of some tests for a university laboratory,\\u000a is presented in the example of the Environmental Radiology Laboratory. Such implementation in a university institution is\\u000a a difficult task, since the setting and environment are both unfavourable. The particularities are the collaboration of many\\u000a independent units of the university,

D. Zapata-García; M. Llauradó; G. Rauret

2007-01-01

302

Feasibility study of a zero-gravity (orbital) atmospheric cloud physics experiments laboratory  

NASA Technical Reports Server (NTRS)

A feasibility and concepts study for a zero-gravity (orbital) atmospheric cloud physics experiment laboratory is discussed. The primary objective was to define a set of cloud physics experiments which will benefit from the near zero-gravity environment of an orbiting spacecraft, identify merits of this environment relative to those of groundbased laboratory facilities, and identify conceptual approaches for the accomplishment of the experiments in an orbiting spacecraft. Solicitation, classification and review of cloud physics experiments for which the advantages of a near zero-gravity environment are evident are described. Identification of experiments for potential early flight opportunities is provided. Several significant accomplishments achieved during the course of this study are presented.

Hollinden, A. B.; Eaton, L. R.

1972-01-01

303

Enhancements in Glovebox Design Resulting from Laboratory-Conducted FIre Tests  

SciTech Connect

The primary mission of the Pit Disassembly and Conversion Facility (PDCF) Project was to disassemble nuclear weapons pits and convert the resulting special nuclear materials to a form suitable for further disposition. Because of the nature of materials involved, the fundamental system which allowed PDCF to perform its mission was a series of integrated and interconnected gloveboxes which provided confinement and containment of the radioactive materials being processed. The high throughput planned for PDCF and the relatively high neutron and gamma radiation levels of the pits required that gloveboxes be shielded to meet worker dose limits. The glovebox shielding material was required to contain high hydrogen concentrations which typically result in these materials being combustible. High combustible loadings created design challenges for the facility fire suppression and ventilation system design. Combustible loading estimates for the PDCF Plutonium (Pu) Processing Building increased significantly due to these shielding requirements. As a result, the estimates of combustible loading substantially exceeded values used to support fire and facility safety analyses. To ensure a valid basis for combustible loading contributed by the glovebox system, the PDCF Project funded a series of fire tests conducted by the Southwest Research Institute on door panels and a representative glovebox containing Water Extended Polyester (WEP) radiological shielding to observe their behavior during a fire event. Improvements to PDCF glovebox designs were implemented based on lessons learned during the fire test. In particular, methods were developed to provide high levels of neutron shielding while maintaining combustible loading in the glovebox shells at low levels. Additionally, the fire test results led to design modifications to mitigate pressure increases observed during the fire test in order to maintain the integrity of the WEP cladding. These changes resulted in significantly reducing the credited combustible loading of the facility. These advances in glovebox design should be considered for application in nuclear facilities within the Department of Energy complex in the future.

Brooks, Kriston P.; Wunderlich, Gregory M.; Mcentire, James R.; Richmond, William G.

2013-06-14

304

Case-Study Investigation of Equine Maternity via PCR-RFLP: A Biochemistry Laboratory Experiment  

PubMed Central

A simple and robust biochemistry laboratory experiment is described that uses restriction fragment length polymorphism (RFLP) of polymerase chain reaction (PCR) products to verify the identity of a potentially valuable horse. During the first laboratory period, students purify DNA from equine samples and amplify two loci of mitochondrial DNA. During the second laboratory period, students digest PCR products with restriction enzymes and analyze the fragment sizes through agarose gel electrophoresis. An optional step of validating DNA extracts through realtime PCR can expand the experiment to three weeks. This experiment, which has an engaging and versatile scenario, provides students with exposure to key principles and techniques of molecular biology, bioinformatics, and evolution in a forensic context. PMID:24363455

Millard, Julie T.; Chuang, Edward; Lucas, James S.; Nagy, Erzsebet E.; Davis, Griffin T.

2013-01-01

305

Recirculation System for Geothermal Energy Recovery in Sedimentary Formations: Laboratory Experiments and Numerical Simulations  

NASA Astrophysics Data System (ADS)

Geothermal energy resources are more widespread than previously thought and have the potential for providing a significant amount of sustainable clean energy worldwide. In particular, hot permeable sedimentary formations provide many advantages over traditional geothermal recovery and enhanced geothermal systems in low permeability crystalline formations. These include: (1) eliminating the need for hydraulic fracturing, (2) significant reduction in risk for induced seismicity, (3) reducing the need for surface wastewater disposal, (4) contributing to decreases in greenhouse gases, and (5) potential use for CO2 sequestration. Advances in horizontal drilling, completion, and production technology from the oil and gas industry can now be applied to unlock these geothermal resources. Here, we present experimental results from a laboratory scale circulation system and numerical simulations aimed at quantifying the heat transfer capacity of sedimentary rocks. Our experiments consist of fluid flow through a saturated and pressurized sedimentary disc of 23-cm diameter and 3.8-cm thickness heated along its circumference at a constant temperature. Injection and production ports are 7.6-cm apart in the center of the disc. We used DI de-aired water and mineral oil as working fluids and explored temperatures from 20 to 150 oC and flow rates from 2 to 30 ml/min. We performed experiments on sandstone samples (Castlegate and Kirby) with different porosity, permeability and thermal conductivity to evaluate the effect of hydraulic and thermal properties on the heat transfer capacity of sediments. The producing fluid temperature followed an exponential form with time scale transients between 15 and 45 min. Steady state outflow temperatures varied between 60% and 95% of the set boundary temperature, higher percentages were observed for lower temperatures and flow rates. We used the flow and heat transport simulator TOUGH2 to develop a numerical model of our laboratory setting. Given the remarkable match between our observations and numerical results, we extended our model to explore a wider range of thermal and hydrological parameters beyond the experimental conditions. Our results prove the capability of heat transfer in sedimentary formations for geothermal energy production.) Sandstone sample with two thermally insulating Teflon caps (white discs). In and out arrows indicate the flow direction while the sample is heated along its circumference (heater not shown). B) Example of a 2D temperature distribution during injection. White x shows the location of the flow ports, inlet (left) and outlet (right). Red is the set boundary temperature and blue is the fluid temperature at the inlet.

Elkhoury, J. E.; Detwiler, R. L.; Serajian, V.; Bruno, M. S.

2012-12-01

306

A laboratory experiment on EM backscatter from Farley-Buneman and gradient drift waves  

NASA Technical Reports Server (NTRS)

Results of laboratory experiment on Bragg backscatter of 3-cm microwaves by turbulent waves driven by the Farley-Buneman and gradient drift instabilities are reported. It is noted that the study is the third in a series of laboratory experiments performed to test, under controlled conditions, prevalent ideas on EM scattering by equatorial and high-latitude ionospheric waves and irregularities. It is shown through separate backscattering from fast and slow ion beam modes that a beam of EM radiation actually provides, in backscatter, information on the spectral content of the scattering medium.

Alport, M. J.; Dangelo, N.; Pecseli, H. L.

1981-01-01

307

Development and Operation of a MUMPS Laboratory Information System: A Decade's Experience  

PubMed Central

We describe more than a decade's experience with inhouse development and operation of a clinical laboratory computer system written in the MUMPS programming language for a 1000 bed teaching hospital. The JHLIS is a networked minicomputer system that supports accessioning, instrument monitoring, and result reporting for over 3000 specimens and 30,000 test results daily. Development and operation of the system accounts for 6% of the budget of the laboratories which have had a 70% increase in workload over the past decade. Our experience with purchased MUMPS software maintained and enhanced inhouse suggests an attractive alternative to lengthy inhouse development.

Miller, R. E.; Causey, J. P.; Moore, G. W.; Wilk, G. E.

1988-01-01

308

Measurement of advective soil gas flux: Results of field and laboratory experiments with CO2  

SciTech Connect

We modified our multi-channel, steady-state flow-through (SSFT), soil-CO2 flux monitoring system to include an array of inexpensive pyroelectric non-dispersive infrared detectors for full-range (0-100%) coverage of CO2 concentrations without dilution, and a larger-diameter vent tube. We then conducted field testing of this system from late July through mid-September 2010 at the Zero Emissions Research and Technology (ZERT) project site located in Bozeman, MT, and subsequently, laboratory testing at the Pacific Northwest National Laboratory (PNNL) in Richland, WA using a flux bucket filled with dry sand. In the field, an array of twenty-five SSFT and three non-steady-state (NSS) flux chambers was installed in a 10x4 m area, the long boundary of which was directly above a shallow (2-m depth) horizontal injection well located 0.5 m below the water table. Two additional chambers (one SSFT and one NSS) were installed 10 m from the well for background measurements. Volumetric soil moisture sensors were installed at each SSFT chamber to measure mean levels in the top 0.15 m of soil. A total flux of 52 kg CO2 d-1 was injected into the well for 27 d and the efflux from the soil was monitored by the chambers before, during, and for 27 d after the injection. Overall, the results were consistent with those from previous years, showing a radial efflux pattern centered on a known “hot spot”, rapid responses to changes in injection rate and wind power, evidence for movement of the CO2 plume during the injection, and nominal flux levels from the SSFT chambers that were up to 6-fold higher than those measured by adjacent NSS chambers. Soil moisture levels varied during the experiment from moderate to near saturation with the highest levels occurring consistently at the hot spot. The effects of wind on measured flux were complex and decreased as soil moisture content increased. In the laboratory, flux bucket testing with the SSFT chamber showed large measured-flux enhancement due to the Venturi effect on the chamber vent, but an overall decrease in measured flux when wind also reached the sand surface. Flux-bucket tests at a high flux (comparable to that at the hot spot) also showed that the measured flux levels increase linearly with the chamber-flushing rate until the actual level is reached. At the SSFT chamber-flushing rate used in the field experiment the measured flux in the laboratory was only about a third of the actual flux. The ratio of measured to actual flux increased logarithmically as flux decreased, and reached parity at low levels typical of diffusive flux systems. Taken together, our results suggest that values for advective CO2 flux measured by SSFT and NSS chamber systems are likely to be significantly lower than the actual values due to back pressure developed in the chamber that diverts flux from entering the chamber. Chamber designs that counteract the back pressure and also avoid large Venturi effects associated with vent tubes, such as the SSFT with a narrow vent tube operated at a high chamber-flushing rate, are likely to yield flux measurements closer to the true values.

Amonette, James E.; Barr, Jonathan L.; Erikson, Rebecca L.; Dobeck, Laura M.; Barr, Jamie L.; Shaw, Joseph A.

2013-10-01

309

The Effects of Initial Condition of Fracture Surfaces, Acid Spending, and Type on Conductivity of Acid Fracture  

E-print Network

Fracture conductivity and the effects of treatment variables can be studied in the laboratory. We conducted experiments based on scaling down the field conditions to laboratory scale by matching Reynold’s and Peclet numbers. Experiments conducted...

Almomen, Ali Mansour

2013-07-24

310

Soil Science self-learning based on the design and conduction of experiments  

NASA Astrophysics Data System (ADS)

This paper presents an experience for introducing the methodology of project-based learning (PBL) in the area of Soil Science in the University of Sevilla (Spain). Currently, teachers try to enhance practical experience of university students in a complementary manner to theoretical knowledge. However, many times this is a difficult process. Practice is an important part of personal work in the vast majority of subjects that degree students receive, since the implementation of the EHEA. In most cases, these experiences are presented as partial small experiments or projects, assigned to the area-specific knowledge agenda. Certain sciences, such as Soil Science, however, require synthesis and integration capabilities of previous knowledge. It is therefore necessary to develop practical programs that address the student not only to the performance of laboratory determinations, but to the formulation of hypotheses, experimental design and problem solving, whether in groups or individually, situated in a wide context and allowing students to make connections with other areas of knowledge. This project involves the development of teamwork experiments, for the study real cases and problems and making decisions in the field of Soil Science. The results of the experimental work were publicly exposed as posters and oral presentations and were discussed during a mini-congress open to students and a general audience. The open and dynamic nature of the project substantially improves student motivation, which adds value to our project. Due to the multidisciplinary character of Soil Science it is relatively easy to propose projects of some complexity, and therefore, provides good conditions for introducing the PBL methodology. The teacher's role is also important and is not limited to observe or qualify the students, but it is a catalyst for learning. It is important that teacher give the leadership of the process and make the students themselves feel the protagonists of the project.

Jordán, A.; Bárcenas-Moreno, G.; Zavala, L. M.

2012-04-01

311

STS-47 MS / PLC Lee conducts SLJ experiment M20 using the image furnace  

NASA Technical Reports Server (NTRS)

STS-47 Mission Specialist (MS) and Payload Commander (PLC) Mark C. Lee, wearing rubber gloves, prepares to load raw material (or crystal seed material) into the upper shaft (or lower shaft) of the Image Furnace. Lee is conducting Spacelab Japan (SLJ) experiment M20, Growth of Samarskite Crystal in Microgravity, during which a single crystal will be produced using the traveling solvent float zone method. The Image Furnace is located in SLJ NASDA Material Sciences Rack 8. SLJ science module is in the payload bay (PLB) of the Earth-orbiting Endeavour, Orbiter Vehicle (OV) 105.

1992-01-01

312

Variable conductance heat pipe technology. [research project resulting in heat pipe experiment on OAO-3 satellite  

NASA Technical Reports Server (NTRS)

A research and development program in variable conductance heat pipe technology is reported. The project involved: (1) theoretical and/or experimental studies in hydrostatics, (2) hydrodynamics, (3) heat transfer into and out of the pipe, (4) fluid selection, and (5) materials compatibility. The development, fabrication, and test of the space hardware resulted in a successful flight of the heat pipe experiment on the OAO-3 satellite. A summary of the program is provided and a guide to the location of publications on the project is included.

Anderson, W. T.; Edwards, D. K.; Eninger, J. E.; Marcus, B. D.

1974-01-01

313

STS-57 Pilot Duffy conducts TDS experiment in SPACEHAB-01 aboard OV-105  

NASA Technical Reports Server (NTRS)

STS-57 Pilot Brian J. Duffy, at a SPACEHAB-01 (Commercial Middeck Augmentation Module (CMAM)) work bench, adjusts wire crimping tool onboard the Earth-orbiting Endeavour, Orbiter Vehicle (OV) 105. Duffy is conducting a soldering experiment (SE) which is part of the Tools and Diagnostic Systems (TDS) project. A printed circuit board, positioned in a specially designed holder and containing 45 connection points, sits on the bench. TDS' sponsor is the Flight Crew Support Division, Space and Life Sciences Directorate, JSC. It represents a group of equipment selected from tools and diagnostic hardware to be supported by the Space Station program. TDS was designed to demonstrate the maintenance of experiment hardware on-orbit and to evaluate the adequacy of its design and the crew interface.

1993-01-01

314

Gunite and associated tanks dry well conductivity monitoring report, Oak Ridge National Laboratory, Oak Ridge, Tennessee, February 1998--December 1998  

SciTech Connect

A waste removal program is being implemented for the Gunite and Associated Tanks Operable Unit at Oak Ridge National Laboratory, Oak Ridge, Tennessee. The waste is being removed by means of remotely operated, in-tank, confined sluicing equipment. During sluicing operations the dry wells adjacent to each of the tanks are instrumented so that potential releases can be detected by means external to the tank. The method of detection is by monitoring the electrical conductivity of the water in the dry well associated with each tank. This report documents the dry well conductivity monitoring data for the period from February 1998 through December 1998. The dry wells monitored during this period include DW-5, DW-6, DW-7, DW-8, DW-9 and DW-10. The conductivity of the water passing through Pump Station 1 (PS1) was also monitored. During this period the sluicing activities at Tank W-6 were initiated and successfully completed. In addition, flight mixers were used to remove wastes from Tank W-5, and sluicing operations were initiated on Tank W-7. Presented in this report are the dry well conductivity, rainfall, tank level, and other appropriate information relevant to the analysis and interpretation of the monitoring data for the reporting period. A thorough analysis of the monitoring results from the six dry wells in the STF and PS1 for the period between February 1998 and December 1998 indicates that no releases have occurred from the gunite tanks being monitored. Overall, the dry well conductivity monitoring continues to provide a robust and sensitive method for detecting potential releases from the gunite tanks and for monitoring seasonal and construction-related changes in the dry well and drain system.

NONE

1999-04-01

315

Intraguild predation, cannibalism, and microhabitat use in Calopteryx virgo and Somatochlora metallica larvae: a laboratory experiment  

Microsoft Academic Search

Intraguild predation (IGP) and cannibalism among co-occurring lotic odonate species was studied in Central Finland. A laboratory\\u000a experiment was performed to assess the microhabitat use and cannibalism between intermediate and late instars of Calopteryx virgo larvae and predation by larger Somatochlora metallica larvae on the intermediate C. virgo instars. The experiment was run in small running-water aquaria where the larvae

Jari Ilmonen; Jukka Suhonen

2006-01-01

316

Making sense from space-time data in laboratory experiments on space plasma processes  

NASA Technical Reports Server (NTRS)

A number of visualization techniques are discussed in a laboratory experiment designed to study phenomena that occur in space. Visualization tools are used to design the apparatus, collect data, and make one-, two-, and three-dimensional plots of the results. These tools are an indispensable part of the experiment because the data sets are hundreds of megabytes in size and rapid turnaround is required.

Gekelman, Walter; Bamber, James; Leneman, David; Vincena, Steve; Maggs, James; Rosenberg, Steve

1995-01-01

317

Collisionless plasma interpenetration in a strong magnetic field for laboratory astrophysics experiments  

E-print Network

A theoretical analysis for astrophysics-oriented laser-matter interaction experiments in the presence of a strong ambient magnetic field is presented. It is shown that the plasma collision in the ambient magnetic field implies significant perturbations in the electron density and magnetic field distribution. This transient stage is difficult to observe in astrophysical phenomena, but it could be investigated in laboratory experiments. Analytic models are presented, which are supported by particle-in-cell simulations.

Korneev, Philipp; Tikhonchuk, Vladimir

2014-01-01

318

Insights From Laboratory Experiments On Simulated Faults With Application To Fracture Evolution In Geothermal Systems  

SciTech Connect

Laboratory experiments provide a wealth of information related to mechanics of fracture initiation, fracture propagation processes, factors influencing fault strength, and spatio-temporal evolution of fracture properties. Much of the existing literature reports on laboratory studies involving a coupling of thermal, hydraulic, mechanical, and/or chemical processes. As these processes operate within subsurface environments exploited for their energy resource, laboratory results provide insights into factors influencing the mechanical and hydraulic properties of geothermal systems. I report on laboratory observations of strength and fluid transport properties during deformation of simulated faults. The results show systematic trends that vary with stress state, deformation rate, thermal conditions, fluid content, and rock composition. When related to geophysical and geologic measurements obtained from engineered geothermal systems (e.g. microseismicity, wellbore studies, tracer analysis), laboratory results provide a means by which the evolving thermal reservoir can be interpreted in terms of physico-chemical processes. For example, estimates of energy release and microearthquake locations from seismic moment tensor analysis can be related to strength variations observed from friction experiments. Such correlations between laboratory and field data allow for better interpretations about the evolving mechanical and fluid transport properties in the geothermal reservoir – ultimately leading to improvements in managing the resource.

Stephen L. Karner, Ph.D

2006-06-01

319

Off-state conductance measurements of the NIST/Lockheed Martin miniature pulse tube flight cryocooler: Laboratory vs. Space  

NASA Astrophysics Data System (ADS)

A two-stage miniature pulse tube (PT) cryocooler, designed for a Space Shuttle flight demonstration, was built and tested at Lockheed Martin Astronautics (LMA) and at the NIST Boulder Lab. The Miniature PT Flight Cryocooler (MPTFC) was designed to provide 0.15 W of cooling at 80 K with heat rejection at 275 K. It was developed as the smallest cryocooler of its kind for the purpose of demonstrating launch survivability and thermal performance in a zero-g environment. The flight version was fabricated as a Getaway Special (GAS) Payload. Although on-orbit cooling performance was not demonstrated because of failed primary batteries, the first off-state PT thermal conductance measurements in zero-g were conducted successfully using the secondary battery system. The data acquisition system and all flight diagnostic sensors performed nominally to provide 15 hours of zero-g warm-up data. The results of the cold head thermal conductance measurements both in zero-g aboard STS-90 and in the laboratory environment are compared to a thermal model for the two-stage PT, detailed in a separate presentation.

Ladner, D. R.; Radebaugh, R.; Bradley, P.

2002-05-01

320

EM laboratories for linear coupling  

SciTech Connect

Broadband, well calibrated, sensitive, and automated laboratories are essential for conducting meaningful phenomenology and susceptibility characterization studies. This presentation gives an overview reflecting the facilities and experiences at Lawrence Livermore National Laboratory.

King, R.J.; Hudson, H.G.; McLeod R.R.

1987-01-01

321

A Static Method as an Alternative to Gel Chromatography: An Experiment for the Undergraduate Biochemistry Laboratory  

ERIC Educational Resources Information Center

This article describes a static method as an alternative to gel chromatography, which may be used as an undergraduate laboratory experiment. In this method, a constant mass of Sephadex gel is swollen in a series of protein solutions. UV-vis spectrophotometry is used to find a partition coefficient, KD, that indicates the fraction of the interior…

Burum, Alex D.; Splittgerber, Allan G.

2008-01-01

322

Ice Sample Production Techniques and Indentation Tests for Laboratory Experiments Simulating Ship Collisions with Ice  

E-print Network

with which engineers analyze structural responses to sea ice ­ as an extension of pure ice behaviour and the vast range of sea ice phenomena encountered. The result of this situation is that a combinationIce Sample Production Techniques and Indentation Tests for Laboratory Experiments Simulating Ship

Bruneau, Steve

323

Kinetics of Carboxylesterase: An Experiment for Biochemistry and Physical Chemistry Laboratory.  

ERIC Educational Resources Information Center

Describes a convenient, inexpensive experiment in enzyme kinetics developed for the undergraduate biochemistry laboratory at the University of Virginia. Required are a single beam visible spectrophotometer with output to a recorder, a constant temperature, a commercially available enzyme, substrates, and buffers. (BT)

Nichols, C. S.; Cromartie, T. H.

1979-01-01

324

Quantum Dots in a Polymer Composite: A Convenient Particle-in-a-Box Laboratory Experiment  

ERIC Educational Resources Information Center

Semiconductor quantum dots are at the forefront of materials science chemistry with applications in biological imaging and photovoltaic technologies. We have developed a simple laboratory experiment to measure the quantum-dot size from fluorescence spectra. A major roadblock of quantum-dot based exercises is the particle synthesis and handling;…

Rice, Charles V.; Giffin, Guinevere A.

2008-01-01

325

Theory and laboratory experiments of elastic wave scattering by dry planar fractures  

E-print Network

Theory and laboratory experiments of elastic wave scattering by dry planar fractures Thomas E. Blum; accepted 3 June 2011; published 30 August 2011. [1] Remote sensing of fractures with elastic waves, fractures control the flow of fluids such as water, hydrocarbons or magma. While previous analytic

Boise State University

326

Microwave-Assisted Esterification: A Discovery-Based Microscale Laboratory Experiment  

ERIC Educational Resources Information Center

An undergraduate organic chemistry laboratory experiment has been developed that features a discovery-based microscale Fischer esterification utilizing a microwave reactor. Students individually synthesize a unique ester from known sets of alcohols and carboxylic acids. Each student identifies the best reaction conditions given their particular…

Reilly, Maureen K.; King, Ryan P.; Wagner, Alexander J.; King, Susan M.

2014-01-01

327

Preparations for a high gradient inverse free electron laser experiment at Brookhaven national laboratory  

SciTech Connect

Preparations for an inverse free electron laser experiment at Brookhaven National Laboratory's Accelerator Test Facilty are presented. Details of the experimental setup including beam and laser transport optics are first discussed. Next, the driving laser pulse structure is investigated and initial diagnostics are explored and compared to simulations. Finally, planned improvements to the experimental setup are discussed.

Duris, J.; Li, R. K.; Musumeci, P.; Sakai, Y.; Threlkeld, E.; Williams, O.; Fedurin, M.; Kusche, K.; Pogorelsky, I.; Polyanskiy, M.; Yakimenko, V. [UCLA Department of Physics and Astronomy, Los Angeles, CA 90095 (United States); Accelerator Test Facility, Brookhaven National Laboratory, Upton, NY, 11973 (United States)

2012-12-21

328

Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus Nitidus (Collembola: Entomobryidae)  

E-print Network

1 Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus Nitidus are often found more abundantly in soils with earthworms than in soils without. Earthworms probably create a favourable environment for microarthropods but few studies have aimed to explain this earthworm effect

Paris-Sud XI, Université de

329

Coulometric Titration of Ethylenediaminetetraacetate (EDTA) with Spectrophotometric Endpoint Detection: An Experiment for the Instrumental Analysis Laboratory  

ERIC Educational Resources Information Center

Ethylenediaminetetraacetate (EDTA) is commonly used as an anticoagulant in blood-collection procedures. In this experiment for the instrumental analysis laboratory, students determine the quantity of EDTA in commercial collection tubes by coulometric titration with electrolytically generated Cu[superscript 2+]. The endpoint is detected…

Williams, Kathryn R.; Young, Vaneica Y.; Killian, Benjamin J.

2011-01-01

330

UPTAKE AND LOSS OF PETROLEUM HYDROCARBONS BY THE MUSSEL, MYTILUS EDULIS, IN LABORATORY EXPERIMENTS  

E-print Network

UPTAKE AND LOSS OF PETROLEUM HYDROCARBONS BY THE MUSSEL, MYTILUS EDULIS, IN LABORATORY EXPERIMENTS ROBERT C. CLARK, JR., AND JOHN S. FINLEY' ABSTRACT Petroleum paraffin hydrocarbons (n-CI4H30 to n-C37H76 system that simulated tides. The mussels were exposed to levels of petroleum hydrocarbons from a surface

331

An Advanced Undergraduate Chemistry Laboratory Experiment Exploring NIR Spectroscopy and Chemometrics  

ERIC Educational Resources Information Center

An advanced undergraduate chemistry laboratory experiment to study the advantages and hazards of the coupling of NIR spectroscopy and chemometrics is described. The combination is commonly used for analysis and process control of various ingredients used in agriculture, petroleum and food products.

Wanke, Randall; Stauffer, Jennifer

2007-01-01

332

Determination of Mercury in Milk by Cold Vapor Atomic Fluorescence: A Green Analytical Chemistry Laboratory Experiment  

ERIC Educational Resources Information Center

Green analytical chemistry principles were introduced to undergraduate students in a laboratory experiment focused on determining the mercury concentration in cow and goat milk. In addition to traditional goals, such as accuracy, precision, sensitivity, and limits of detection in method selection and development, attention was paid to the…

Armenta, Sergio; de la Guardia, Miguel

2011-01-01

333

Women's Experiences in the Engineering Laboratory in Japan  

ERIC Educational Resources Information Center

This qualitative study aims to examine Japanese women undergraduate engineering students' experiences of interacting with departmental peers of the same year in the laboratory setting by using interview data of 32 final-year students at two modestly selective national universities in Japan. Expectation state theory that explains unequal…

Hosaka, Masako

2014-01-01

334

Bacterial Production of Poly(3-hydroxybutyrate): An Undergraduate Student Laboratory Experiment  

ERIC Educational Resources Information Center

As part of a multidisciplinary course that is cross-listed between five departments, we developed an undergraduate student laboratory experiment for culturing, isolating, and purifying the biopolymer, poly(3-hydroxybutyrate), PHB. This biopolyester accumulates in the cytoplasm of bacterial cells under specific growth conditions, and it has…

Burns, Kristi L.; Oldham, Charlie D.; May, Sheldon W.

2009-01-01

335

The Kinetics and Inhibition of Gamma-Glutamyl Transpeptidase: A Biochemistry Laboratory Experiment.  

ERIC Educational Resources Information Center

Discusses an enzyme kinetics laboratory experiment involving a two substrate system for undergraduate biochemistry. Uses the enzyme gamma-glutamyl transpeptidase as this enzyme in blood serum is of clinical significance. Notes elevated levels are seen in liver disease, alcoholism, and epilepsy. Uses a spectrophotometer for the analysis. (MVL)

Splittgerber, A. G.; Sohl, Julie

1988-01-01

336

A controllability-stabilizability result for the NASA-IEEE Spacecraft Control Laboratory Experiment (SCOLE) configuration  

NASA Technical Reports Server (NTRS)

A nonlinear distributed parameter model for the NASA-Institute of Electrical and Electronics Engineers' Spacecraft Control Laboratory Experiment (SCOLE) configuration is considered. A linear feedback control law is proposed that points the line of sight of the antenna to any given target direction and at the same time stabilizes the oscillations of the entire flexible configuration.

Araya, Roberto

1984-01-01

337

Food partitioning by lake-dwelling triclads and glossiphoniid leeches: field and laboratory experiments  

Microsoft Academic Search

The triclads Polycelis tenuis and Dugesia polychroa and the glossiphoniid leeches Glossiphonia complanata and Helobdella stagnalis are abundant on the stony shores of productive British lakes. All species are food limited and there is considerable overlap in the diets of these triclads and leeches. This paper investigates interactions between the two groups using field and laboratory experiments to try to

R. M. H. Seaby; A. J. Martin; J. O. Young

1996-01-01

338

Usnic Acid and the Intramolecular Hydrogen Bond: A Computational Experiment for the Organic Laboratory  

ERIC Educational Resources Information Center

A computational experiment is described for the organic chemistry laboratory that allows students to estimate the relative strengths of the intramolecular hydrogen bonds of usnic and isousnic acids, two related lichen secondary metabolites. Students first extract and purify usnic acid from common lichens and obtain [superscript 1]H NMR and IR…

Green, Thomas K.; Lane, Charles A.

2006-01-01

339

Ring-Closing Metathesis: An Advanced Guided-Inquiry Experiment for the Organic Laboratory  

ERIC Educational Resources Information Center

The design and implementation of an advanced guided-inquiry experiment for the organic laboratory is described. Grubbs's second-generation catalyst is used to effect the ring-closing metathesis of diethyl diallylmalonate. The reaction is carried out under an inert atmosphere at room temperature and monitored by argentic TLC. The crude reaction is…

Schepmann, Hala G.; Mynderse, Michelle

2010-01-01

340

Crop yield and light / energy efficiency in a closed ecological system: two laboratory biosphere experiments  

NASA Astrophysics Data System (ADS)

Two crop growth experiments in the soil-based closed ecological facity, Laboratory Biosphere, were conducted from 2003-2004 with candidate space life support crops. Apogee wheat (Utah State University variety) was grown, planted in 2 densities, 400 and 800 seeds m-2. The lighting regime for the wheat crop was 16 hours of light -- 8 hours dark at a total light intensity of around 840 mol m2 sec-1 and 48.4 mol m-2 d-1 over 84 days Average biomass was 1395 g m-2, 16.0 g m-2 day-1 and average seed production was 689 g m-2 and 7.9 g m2 day-1. The less densely planted side was more productive than the denser planting, with 1634 g m-2 and 18.8g m-2 day-1 of biomass vs. 1156 g m-2 and 13.3 g m-2 day-1; and a seed harvest of 812.3 g m-2 and 9.3 g m-2 day-1 vs. 566.5 g m-2 and 6.5 g m-2 day-1 Harvest index was 0.49 for the wheat crop. The experiment with sweet potato used TU-82-155, a compact variety developed at Tuskegee University. Light during the sweet potato experiment, on a 16 hour on/8 hours dark cycle, totalled 5568 total moles of light in 126 days for the sweet potatoes, or an average of 44.2 moles m-2 day-1. Temperature regime was 28 deg +/- 3 deg C day /22 deg +/- 4 deg C night. Sweet potato tuber yield was 39.7 kg wet weight, or an average of 7.4 kg m-2 and 7.7 kg dry weight of tubers since dry weight was about 18.6% wet weight.^Average per day production was 58.7 g m-2 day-1 wet weight and 11.3 g m-2 day-1. For the wheat, average light efficiency was 0.34 grams biomass per mole, and 0.17 grams seed per mole. The best area of wheat had an efficiency of light utilization of 0.51 g biomass per mole and 0.22 g seed per mole. For the sweet potato crop, light efficiency per tuber wet weight was 7.13 g/mole and 1.38 g dry weight of tuber per mole of light. The best area of tuber production had 9.49 g/mole wet weight and 1.85 g/mole of light dry weight. Production from the wheat was The Laboratory Biosphere experiment's light efficiency was somewhat higher than the USU field results but somewhat below greenhouse trials at comparable light levels, and the best portion of the crop at 0.22g/mole was inbetween those values. Sweet potato production was overall close to 50% higher than trials using hydroponic methods with TU-82-155 at NASA JSC. Compared to projected yields for the Mars on Earth life support system, these wheat yields were about 15% higher, and the sweet potato yields averaged over 80% higher

Nelson, M.; Dempster, W. F.; Silverstone, S.; Alling, A.; Allen, J. P.; van Thillo, M.

341

GAAT dry well conductivity monitoring report, July 1997 through January 1998, Oak Ridge National Laboratory, Oak Ridge, Tennessee  

SciTech Connect

A waste removal program is being implemented for the Gunite and Associated Tanks (GAAT) Operable Unit at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee. The waste is being removed by means of remotely operated, in-tank, confined sluicing equipment. The waste removal operations in Tanks W-3 and W-4 in the North Tank Farm (NTF) have been completed and the equipment is being moved to the South Tank Farm (STF), where it will be used to remove the sludges from the six STF tanks (W-5, W-6, W-7, W-8, W-9, and W-10) beginning later this year. During sluicing operations the dry wells adjacent to each of the tanks are instrumented so that potential releases can be detected by means external to the tank. The method of detection is by monitoring the electrical conductivity of the water in the dry well associated with each tank. This report documents the dry well conductivity monitoring data for the period from July 1997 through January 1998. The dry wells monitored during this period include DW-3, DW-4, DW-8, DW-9, and DW-10. The conductivity of the water passing through Pump Station 1 (PS 1) was also monitored. The principal activities that occurred during this period were the sluicing of Tanks W-3 and W-4 in the NTF, transfer of tank liquids from the NTF to the STF, and the installation of new risers, tank dome leveling, and emplacement of stabilized base backfill in the STF. Presented in this report are the dry well conductivity, rainfall, tank level, and STF construction information that is relevant to the analysis and interpretation of the monitoring data for the reporting period. A thorough analysis of the monitoring results for the period indicates that no releases have occurred from the gunite tanks being monitored.

NONE

1998-03-13

342

Summary of activities of the life cycle costing workshop conducted by the Environmental Restoration Program of Oak Ridge National Laboratory  

SciTech Connect

A five-day life cycle workshop was conducted by the Environmental Restoration (FR) Program of Oak Ridge National Laboratory (ORNL) to develop appropriate remediation scenarios for each Waste Area Grouping (WAG) at ORNL and to identify associated data needs (e.g., remedial investigations, special studies, and technology demonstrations) and required interfaces. Workshop participants represented the Department of Energy, Martin Marietta Energy Systems, Inc., Bechtel National, Radian Corporation, EBASCO Corporation, and M-K Ferguson. The workshop was used to establish a technical basis for remediation activities at each WAG. The workshop results are documented in this report and provide the baseline for estimating the technical scope for each WAG. The scope and associated budgets and schedules will be summarized in baseline reports for each WAG, which, in turn, will be compiled into an overall strategy document for ORNL ER.

Not Available

1992-08-01

343

Procedure for Conducting IACUC Business in the Event of a Pandemic or Other Significant The Office of Laboratory Animal Welfare at NIH (OLAW) expects each institution's IACUC to  

E-print Network

business according to requirements found in the PHS Policy, the Animal Welfare Act and Regulations The Office of Laboratory Animal Welfare at NIH (OLAW) expects each institution's IACUC to continue to conduct

Maryland, Baltimore County, University of

344

Enhancing the Student Experiment Experience: Visible Scientific Inquiry Through a Virtual Chemistry Laboratory  

NASA Astrophysics Data System (ADS)

Practical work is often noted as a core reason many students take on science in secondary schools (high schools). However, there are inherent difficulties associated with classroom practical work that militate against scientific inquiry, an approach espoused by many science educators. The use of interactive simulations to facilitate student inquiry has emerged as a complement to practical work. This study presents case studies of four science teachers using a virtual chemistry laboratory (VCL) with their students in an explicitly guided inquiry manner. Research tools included the use of the Inquiry Science Implementation Scale in a `talk-aloud' manner, Reformed Teaching Observation Protocol for video observations, and teacher interviews. The findings suggest key aspects of practical work that hinder teachers in adequately supporting inquiry and highlight where a VCL can overcome many of these difficulties. The findings also indicate considerations in using the VCL in its own right.

Donnelly, Dermot; O'Reilly, John; McGarr, Oliver

2013-08-01

345

Analytical Plans Supporting The Sludge Batch 8 Glass Variability Study Being Conducted By Energysolutions And Cua's Vitreous State Laboratory  

SciTech Connect

EnergySolutions (ES) and its partner, the Vitreous State Laboratory (VSL) of The Catholic University of America (CUA), are to provide engineering and technical services support to Savannah River Remediation, LLC (SRR) for ongoing operation of the Defense Waste Processing Facility (DWPF) flowsheet as well as for modifications to improve overall plant performance. SRR has requested via a statement of work that ES/VSL conduct a glass variability study (VS) for Sludge Batch 8. SRR issued a technical task request (TTR) asking that the Savannah River National Laboratory (SRNL) provide planning and data reduction support for the ES/VSL effort. This document provides two analytical plans for use by ES/VSL: one plan is to guide the measurement of the chemical composition of the study glasses while the second is to guide the measurement of the durability of the study glasses. The measurements generated by ES/VSL are to be provided to SRNL for data reduction and evaluation. SRNL is to review the results of its evaluation with ES/VSL and SRR. The results will subsequently be incorporated into a joint report with ES/VSL as a deliverable to SRR to support the processing of SB8 at DWPF.

Edwards, T. B.; Peeler, D. K.

2012-11-26

346

Laboratory convection experiments with internal, noncontact, microwave generated heating, applied to Earth's mantle dynamics  

NASA Astrophysics Data System (ADS)

The thermal evolution of terrestrial planets is controlled by secular cooling and internal heating due to the decay of radiogenic isotopes, two processes which are equivalent from the standpoint of convection dynamics. Few studies have been devoted to the intrinsic characteristics of this form of convection, which are dominated by instabilities of a single boundary layer and which involve a non-isentropic interior thermal structure. Laboratory studies of such convection have been plagued by considerable technical difficulties and have been mostly restricted to aqueous solutions with moderate values of the Prandtl number, contrary to planetary mantles. Here, we describe a new laboratory setup to generate internal heating in controlled conditions based on microwave (MW) absorption. The advantages of our technique include, but are not limited to: (1) a volumetric heat source that can be localized or distributed in space, (2) selectively heating part of the volume with time varying intensity and space distribution. Our tank prototype had horizontal dimensions of 30 cm × 30 cm and 5 cm height. A uniform and constant temperature was maintained at the upper boundary by an aluminium heat exchanger and adiabatic conditions were imposed at the tank base. Experimental fluids were hydroxyethylcellulose - water mixtures whose viscosities were varied within a wide range depending on concentration. Experimental Prandtl numbers were set at values larger than 100. Thermochromic Liquid Crystals (TLC) were used to visualize the temperature field, and the velocity field was determined using Particle Image Velocimetry (PIV). The Rayleigh-Roberts number was varied from 105 to 107. We also conducted numerical simulations in 3D cartesian geometry using Stag-3D (Tackley 1993) to reproduce the experimental conditions, including the tank aspect ratio and the temperature dependence of physical properties. We observed that convection is driven by cold descending plumes generated at the upper boundary that induce a diffuse upward return flow. Within experimental error, excellent agreement was found between calculated and observed vertical profiles of the horizontally-averaged temperature. Calculations and experiments led to the same velocity field characteristics including the number of instabilities in the upper boundary layer and root mean square velocity values. P. J. Tackley, Geophys. Res. Lett. 20, 2187-2190 (1993).

Limare, Angela; Surducan, Emanoil; di Giuseppe, Erika; Surducan, Vasile; Neamtu, Camelia; Vilella, Kenny; Fourel, Loic; Farnetani, Cinzia; Kaminski, Edouard; Jaupart, Claude

2014-05-01

347

Laboratory simulation experiments on the solid-state greenhouse effect in planetary ices  

NASA Astrophysics Data System (ADS)

Icy surfaces like the polar caps of Mars, comets, Edgeworth-Kuiper belt objects or the surface areas of many moons in the outer Solar System behave different than rock and soil surfaces when irradiated by solar light. The latter ones absorb and reflect incoming solar radiation immediately at the surface. In contrast, ices are partially transparent in the visible spectral range and opaque in the infrared. Due to this fact it is possible for the solar radiation to reach a certain depth and increase the temperature of the sub-surface layers directly. This internal temperature rise is called "solid-state greenhouse effect," in analogy to the classical greenhouse effect in an atmosphere. It may play an important role in the energy balance of various icy bodies in the Solar System. Within the scope of a project conducted at the Space Research Institute of the Austrian Academy of Sciences in Graz the solid-state greenhouse effect was investigated experimentally and theoretically. A number of experiments with diverse materials, focussing mainly on layered samples with a surface cover consisting of transparent H 2O-ice, were performed. The samples were irradiated under cryo-vacuum conditions by a solar simulator. The temperature distributions inside the samples were measured and compared with the results of numerical model calculations. We found that the predicted sub-surface temperature maximum is very clearly measurable in glass beads samples with various particle size distributions, but can also be detected in transparent compact surface ice layers. However, in the latter case it is less distinct than originally expected. Measuring the effect by laboratory methods turned out to be a difficult task due to the shallow depth where the temperature maximum occurs.

Kaufmann, Erika; Kömle, Norbert I.; Kargl, Günter

2006-11-01

348

Student Reciprocal Peer Teaching as a Method for Active Learning: An Experience in an Electrotechnical Laboratory  

NASA Astrophysics Data System (ADS)

Active learning is one of the most efficient mechanisms for learning, according to the psychology of learning. When students act as teachers for other students, the communication is more fluent and knowledge is transferred easier than in a traditional classroom. This teaching method is referred to in the literature as reciprocal peer teaching. In this study, the method is applied to laboratory sessions of a higher education institution course, and the students who act as teachers are referred to as "laboratory monitors." A particular way to select the monitors and its impact in the final marks is proposed. A total of 181 students participated in the experiment, experiences with laboratory monitors are discussed, and methods for motivating and training laboratory monitors and regular students are proposed. The types of laboratory sessions that can be led by classmates are discussed. This work is related to the changes in teaching methods in the Spanish higher education system, prompted by the Bologna Process for the construction of the European Higher Education Area

Muñoz-García, Miguel A.; Moreda, Guillermo P.; Hernández-Sánchez, Natalia; Valiño, Vanesa

2012-10-01

349

[Inspection of laboratory animal breeding and husbandry/experiments on animals, examples].  

PubMed

In Berlin, the authorization and inspection of experiments on animals and of facilities for laboratory animal breeding and husbandry are carried out by the same authority. According to Section 16 (1) sentence one no. 3 Tierschutzgesetz (German animal protection act), there are presently 1200 procedures registered and 68 facilities approved to breed and keep vertebrates for experiments (according to Section 11 (1) sentence one no. 1 Tierschutzgesetz). In 2006, the use of 300,903 vertebrates was reported. There are 38 animal welfare officers in the twenty major scientific facilities who are in charge of in-house supervision. The authority visits the facilities where experiments take place at regular intervals to observe and supervise their operations. On request, the facilities must send the records from the experiments to the authority for examination (according to Section 9 a Tierschutzgesetz). With the annual laboratory animal report, the authority can verify the number of authorised laboratory animals. By checking the scientific publications the authority can compare them with the authorised animal experiments. Facilities for laboratory animal breeding and husbandry are continuously supervised. Offences against the animal protection act are prosecuted. When there are deficiencies in animal welfare, the authority sets a deadline to correct the defects. If the deficiency still exists after the expiry of the term, the authority imposes a penalty payment or initiates legal proceedings. The important role of the animal welfare officers (Section 8 a Tierschutzgesetz) is apparent. The majority of supervisions show that there are deficiencies. This indicates that more emphasis must be put on prevention. The facilities must provide better support and resources for the animal welfare officers. Furthermore, the scientists must be more receptive to the animal welfare officers in their role as advisers. Continuous and adequate training is imperative to the goal of maintaining sufficient in-house supervision and to keep the animals from suffering. If in-house supervision works well, the State's role in regulating animal experiments can be reduced. PMID:18500148

Ratsch, H

2008-04-01

350

Critical experiments at Sandia National Laboratories : technical meeting on low-power critical facilities and small reactors.  

SciTech Connect

Sandia National Laboratories (SNL) has conducted radiation effects testing for the Department of Energy (DOE) and other contractors supporting the DOE since the 1960's. Over this period, the research reactor facilities at Sandia have had a primary mission to provide appropriate nuclear radiation environments for radiation testing and qualification of electronic components and other devices. The current generation of reactors includes the Annular Core Research Reactor (ACRR), a water-moderated pool-type reactor, fueled by elements constructed from UO2-BeO ceramic fuel pellets, and the Sandia Pulse Reactor III (SPR-III), a bare metal fast burst reactor utilizing a uranium-molybdenum alloy fuel. The SPR-III is currently defueled. The SPR Facility (SPRF) has hosted a series of critical experiments. A purpose-built critical experiment was first operated at the SPRF in the late 1980's. This experiment, called the Space Nuclear Thermal Propulsion Critical Experiment (CX), was designed to explore the reactor physics of a nuclear thermal rocket motor. This experiment was fueled with highly-enriched uranium carbide fuel in annular water-moderated fuel elements. The experiment program was completed and the fuel for the experiment was moved off-site. A second critical experiment, the Burnup Credit Critical Experiment (BUCCX) was operated at Sandia in 2002. The critical assembly for this experiment was based on the assembly used in the CX modified to accommodate low-enriched pin-type fuel in water moderator. This experiment was designed as a platform in which the reactivity effects of specific fission product poisons could be measured. Experiments were carried out on rhodium, an important fission product poison. The fuel and assembly hardware for the BUCCX remains at Sandia and is available for future experimentation. The critical experiment currently in operation at the SPRF is the Seven Percent Critical Experiment (7uPCX). This experiment is designed to provide benchmark reactor physics data to support validation of the reactor physics codes used to design commercial reactor fuel elements in an enrichment range above the current 5% enrichment cap. A first set of critical experiments in the 7uPCX has been completed. More experiments are planned in the 7uPCX series. The critical experiments at Sandia National Laboratories are currently funded by the US Department of Energy Nuclear Criticality Safety Program (NCSP). The NCSP has committed to maintain the critical experiment capability at Sandia and to support the development of a critical experiments training course at the facility. The training course is intended to provide hands-on experiment experience for the training of new and re-training of practicing Nuclear Criticality Safety Engineers. The current plans are for the development of the course to continue through the first part of fiscal year 2011 with the development culminating is the delivery of a prototype of the course in the latter part of the fiscal year. The course will be available in fiscal year 2012.

Harms, Gary A.; Ford, John T.; Barber, Allison Delo

2010-11-01

351

Laboratory Study to Identify the Impact of Fracture Design Parameters over the Final Fracture Conductivity Using the Dynamic Fracture Conductivity Test Procedure  

E-print Network

such as closure stress, and temperature and fracture fluid parameters such as proppant loading over the final conductivity of a hydraulic fracture treatment. With the purpose of estimating the relation between fracture conductivity and the design parameters, two...

Pieve La Rosa, Andres Eduardo

2011-08-08

352

Heat Fluxes and Evaporation Measurements by Multi-Function Heat Pulse Probe: a Laboratory Experiment  

NASA Astrophysics Data System (ADS)

Multi Functional Heat Pulse Probes (MFHPP) are multi-needles probes developed in the last years able to measure temperature, thermal properties such as thermal diffusivity and volumetric heat capacity, from which soil moisture is directly retrieved, and electric conductivity (through a Wenner array). They allow the simultaneous measurement of coupled heat, water and solute transport in porous media, then. The use of only one instrument to estimate different quantities in the same volume and almost at the same time significantly reduces the need to interpolate different measurement types in space and time, increasing the ability to study the interdependencies characterizing the coupled transports, especially of water and heat, and water and solute. A three steps laboratory experiment is realized at EPFL to investigate the effectiveness and reliability of the MFHPP responses in a loamy soil from Conthey, Switzerland. In the first step specific calibration curves of volumetric heat capacity and thermal conductivity as function of known volumetric water content are obtained placing the MFHPP in small samplers filled with the soil homogeneously packed at different saturation degrees. The results are compared with literature values. In the second stage the ability of the MFHPP to measure heat fluxes is tested within a homemade thermally insulated calibration box and results are matched with those by two self-calibrating Heatflux plates (from Huxseflux), placed in the same box. In the last step the MFHPP are used to estimate the cumulative subsurface evaporation inside a small column (30 centimeters height per 8 centimeters inner diameter), placed on a scale, filled with the same loamy soil (homogeneously packed and then saturated) and equipped with a vertical array of four MFHPP inserted close to the surface. The subsurface evaporation is calculated from the difference between the net sensible heat and the net heat storage in the volume scanned by the probes, and the values obtained are matched with the overall evaporation, estimated through the scale in terms of weight loss. A numerical model able to solve the coupled heat-moisture diffusive equations is used to interpolate the obtained measures in the second and third step.

Sharma, V.; Ciocca, F.; Hopmans, J. W.; Kamai, T.; Lunati, I.; Parlange, M. B.

2012-04-01

353

Artificial size frequency distribution indices in laboratory experiments: Implications for understanding the evolution of Itokawa  

NASA Astrophysics Data System (ADS)

Asteroid 25143 Itokawa is a near-Earth irregular asteroid 535 by 294 by 209 meters in size [1]. The surface topography can be divided into the smooth lowlands and the rocky highlands. The origins of these regions could be due to the surface flow of fines from high to low points of gravitational potential [2]. Previous block studies conducted by Michikami et al. [3] and Mazrouei et al. [4] reported average size frequency distribution (SFD) indices on blocks larger than 6 m in diameter to be -3.1 ± 0.1 and -3.5 ± 0.1, respectively. Noviello et al. [5] reported preliminary results showing that blocks from 0.1 to 6 m in diameter had significantly lower SFD indices. They also reported that SFDs created from lowland image analyses consistently yield indices of around -2.71 ± 0.01, while the SFDs from highland images yield indices of roughly -2.00 ± 0.01 at the same scale. There are a number of geologic processes that could be responsible for the observed differences in SFD indices between different topographical regions. To quantify the effects of seismic shaking on SFD indices, we conducted simple laboratory experiments. Blocks were placed in a bin and slowly covered with sand and gravel, and then subjected to periods of moderate shaking in 10-second increments. The same methods used in the observational study were then applied to the experimental blocks to quantify the change in SFD index as the blocks were first covered and subsequently revealed. The initial results are: 1) As blocks are covered, in general the indices decrease; 2) Seismic shaking restores the indices; and 3) Larger blocks reappear faster than smaller rocks after shaking. This has implications for interpreting results of block count studies (the brazil nut effect [6]) and sample return missions, while also providing details about the physical expression of certain geologic processes on small bodies. [1] Fujiwara, A. et al., (2006) Science, 312, 1330-1334. [2] Miyamoto, H. et al., (2007) Science, 316, 1011-1014. [3] Michikami, T. et al., (2008) Earth Planets Space, 60, 13-20. [4] Mazrouei, S. et al., (2014) Icarus 229, 181-189. [5] Noviello, J. L. et al., (2014) LPSC XLV, Abstract #1587. [6] Asphaug, E., et al. (2001) LPSC XXXII, Abstract #1708.

Noviello, Jessica; Barnouin, Olivier S.; Ernst, Carolyn M.; Daly, Michael

2014-11-01

354

Foreshock And Aftershock Sequences: Insight From Laboratory Cyclic Pore Pressure Experiments  

NASA Astrophysics Data System (ADS)

Fluid and fracture interaction are a key mechanism in the Earth's crust, and are not yet fully understood. The effects of pore pressure on pre-existing faults are twofold: Firstly, an increase in pore pressure reduces the effective normal stress that holds the fault locked; giving rise to stick-slip failure. Secondly, pressurized pore fluids may act over time to reduce the strength of the rock through mechanisms such as stress corrosion and static fatigue (creep). The former effect is well-known as the law of effective stress, and is often cited as the reason for the rapid response of seismicity due to fluid pressure changes. However, this law does not account for the permeability change with time, and hence, cannot fully explain the cause of protracted seismicity. The effect of cyclic pore pressure has been speculated as one of the factors that causes protracted seismicity. However, whilst numerous theoretical solutions have been developed to account for the diffusivity and hydraulic conductivity of the fractured zone, a severe paucity of laboratory data exists with which to test such hypotheses. We report new cyclic pore pressure experiments carried out on porous sandstone samples (Fontainebleau), which were pre-fractured using constant strain rate of 2E-6 in a conventional triaxial cell at a confining pressure of 25 MPa and a pore pressure of 5 MPa. Subsequently, different combinations of cyclic pore pressure amplitudes and frequencies were applied; with seismicity response (acoustic emission) measured continuously using a specifically developed continuous data acquisition unit. By recording 16 transducers continuously at 10 MHz sampling frequency to hard disk, we are thus able to reconstruct the temporal and spatial distribution of hypocentres without loss of information due to either the rapid fracture formation or the subtle changes of pore oscillation induced seismicity. Our results show that when the amplitude of pore pressure increase is small (less than 0.5 MPa), a large number of pore pressure cycles are required to induce seismicity on the pre-existing faults. Aseismic slips built up gradually followed by larger magnitude foreshocks and mainshocks along the faults. Conversely, if the pore pressure increase is large (greater than 0.5 MPa), most of the seismic events occur during the first pore pressure cycle, and are subsequently followed by an exponential reduction with successive pore pressure cycles. Our experiments provide a proxy to the seismicity (both initial and protracted) which is observed in field scale reservoir-induced seismicity / aftershock sequences. Furthermore, our results indicate that seismicity can be intensified (i.e. increase in the number of events as well as magnitudes) when the applied pore pressure magnitude exceeds the previous maximum that has been experienced by the sample.

Ying, W.; Benson, P. M.; Young, R.

2008-12-01

355

Laboratory evaporation experiments in undisturbed peat columns for determining peat soil hydraulic properties  

NASA Astrophysics Data System (ADS)

Knowledge about hydraulic properties of organic soils is crucial for the interpretation of the hydrological situation in peatlands. This in turn is the basis for designing optimal rewetting strategies, for assessing the current and future climatic water balance and for quantifying greenhouse gas emissions of CO2, CH4 and N2O, which are strongly controlled by the depth of the peat water table. In contrast to mineral soils, the hydraulic properties of organic soils differ in several aspects. Due to the high amount of organic components, strong heterogeneity, and shrinkage and swelling of peat, accompanied by changing soil volume and bulk density, the applicability of standard hydraulic functions developed for mineral soils for describing peat soil moisture dynamics is often questioned. Hence, the objective of this study was to investigate the applicability of the commonly applied van Genuchten-Mualem (VGM) parameterization and to evaluate model errors for various peat types. Laboratory column experiments with undisturbed peat soils (diameter: 30 cm, height: 20 cm) from 5 different peatlands in Germany were conducted. In numerical simulations using HYDRUS-1D the experimental data were used for an inverse estimation of the soil hydraulic parameters. Using the VGM parameterization, the model errors between observed and measured pressure heads were quantified with a root mean square error (RMSE) of 20 - 65 cm. The RMSE increased for soils with higher organic carbon content and higher porosity. Optimizing the VGM 'tortuosity' parameter (?) instead of fixing it to its default of 0.5 strongly reduced the RMSE, especially for the soils that showed high pressure head gradients during the experiment. Due to the fact, that very negative pressure heads in peatlands occur rarely, we reduced the range of pressured heads in the inversion to a 'field-relevant' range from 0 to -200 cm which strongly reduced the RMSE to 6 - 12 cm and makes the VGM parameterization applicable for all investigated peat soils. For the field-relevant scale, especially for very wet conditions, we demonstrate the importance of macro-pores by using a simple macro-pore approach, with only 1 additional parameter, i.e. the macro-pore fraction, which strongly reduced the RMSE down to 1 - 7 cm. Since ? has not been identified as an important parameter for the field-relevant range, only 5 parameters were optimized in this approach. This keeps the derivation of the parameters manageable and thus provides a model that is applicable to practical issues.

Dettmann, U.; Frahm, E.; Bechtold, M.

2013-12-01

356

Physiological biomarkers of hypoxic stress in red swamp crayfish Procambarus clarkii from field and laboratory experiments.  

PubMed

The crayfish industry in Louisiana is the largest in the United States, with crayfish frequently harvested from waters that experience episodic or chronic hypoxia (dissolved oxygen [DO]? 2 mg/l). We examined physiological biomarkers (hemolymph lactate, glucose, and protein concentrations) of hypoxic stress in the red swamp crayfish Procambarus clarkii from chronically hypoxic natural habitats and laboratory hypoxia experiments. P. clarkii from normoxic and hypoxic areas in the Atchafalaya River Basin were sampled monthly from April to July 2010. Laboratory experiments subjected P. clarkii to severe hypoxia (1 mg/l DO), moderate hypoxia (2 mg/l DO), or normoxic conditions (control: DO>7.5 mg/l) for 12, 24, and 48 h. P. clarkii from normoxic and hypoxic natural habitats did not display significantly different hemolymph lactate or glucose concentrations; however, mean hemolymph protein concentration was significantly lower in crayfish from hypoxic areas. P. clarkii exposed to severe hypoxia in laboratory experiments had significantly higher hemolymph lactate and glucose concentrations for all three exposure times, whereas large differences in protein concentrations were not observed. These results suggest that elevated hemolymph lactate and glucose concentrations are responses to acute hypoxia in P. clarkii, while differences in protein concentrations are the result of chronic hypoxic exposure. PMID:22554447

Bonvillain, Christopher P; Rutherford, D Allen; Kelso, William E; Green, Christopher C

2012-09-01

357

Controlled Quantized Conductance Steps Using a Simple Mechanical System: An Undergraduate Lab Experiment  

NASA Astrophysics Data System (ADS)

We demonstrate clear quantized conductance steps in mechanical break junctions (MBJ) based on a gold wire, a springy-steel bending beam, a micrometer, a 1.5V battery , and a Teflon disc that we rotate manually. The voltage across the wire is measured using a NI-DAQ assistant unit and a simple LabVIEW program. As the wire is stretched, its resistance (i.e. voltage across it) increases gradually then follows a stair-case- like shape, which is a hallmark of quantized conductance, with steps at values of 25.8 k?/2n, where n is an integer. The resistance jumps are clearer and more distinct for smaller n and become closer for larger n, which is a demonstration of the Correspondence Principle. The quantization occurs when the wire is thin enough that its diameter is comparable to the de Broglie wave length of the current-carrying electrons and is a direct consequence of confinement. This experiment is designed for sophomore/junior level undergraduate labs.

Burnett, Christopher; Tolley, Robert; Silvidi, Antony; Eid, Khalid

2011-10-01

358

Transformations in organic sulfur speciation during maturation of Monterey shale: Constraints from laboratory experiments  

Microsoft Academic Search

A series of hydrous pyrolysis experiments were conducted at temperatures ranging from 125 to 360C at 350 bars pressure to examine variations in sulfur speciation during thermal maturation of Monterey shale. The total sediment, kerogen and bitumen from each experiment in addition to unheated representatives were analyzed via x-ray absorption spectroscopy, pyrolysis-gas chromatography, ³°NMR spectrometry, elemental analysis, thin-layer chromatography and

B. C. Nelson; T. I. Eglinton; J. S. Seewald; M. A. Vairavamurthy; F. P. Miknis

1995-01-01

359

Laboratory measurements of dielectric permittivity and electrical conductivity as a function of water content of soils in the intermediate frequency domain (100 kHz - 10 MHz)  

Microsoft Academic Search

This study focuses on the measurement of the electrical properties of soils in the intermediate frequency range (100 kHz - 10 MHz). The mapping of the soil moisture, necessitating the mapping the electrical properties in situ, requires preliminary laboratory measurements conducted under controlled conditions. The effective electrical conductivity sigma(?) is usually measured in the low frequency range ( 50 MHz),

Pauline Kessouri; Fayçal Rejiba; Cyril Schamper; Alain Tabbagh

2010-01-01

360

Stimulated Raman scatter analyses of experiments conducted at the National Ignition Facility  

NASA Astrophysics Data System (ADS)

The recent energetics campaignootnotetextN. B. Meezan et al., Phys. Plasmas 17, 056304 (2010). conducted at the National Ignition Facility in Fall, 2009 achieved its two main goals: providing radiation drive and symmetry suitable for subsequent ignition experiments. Many diagnostics were fielded during this campaign, one of which provided a time-resolved wavelength spectrum of light reflected from the target by stimulated Raman scatter (SRS). SRS occurs when incident light reflects off self-generated electron plasma waves. The SRS spectrum of an inner cone quad has provided insight into these experiments. Analyses indicate that synthetic SRS diagnostics better match those of experiments when an atomic physics model with greater emissivity is utilized, along with less inhibited electron transport (higher flux, with, ideally, nonlocal electron transport). With these models,ootnotetextM. D. Rosen, this conference. SRS primarily occurs in a region of the target where nearest-neighbor 23^o quads significantly overlap the diagnosed 30^o quad. This increases the gain at lower density (lower wavelength), a feature consistent with experimental results. Other predicted features, such as the direction and spreading of the SRS as well as its intensity, are also in better agreement with experiment. Inclusion of this effect of multiple beams sharing a reflected SRS light wave has resulted in modifications to our laser-plasma interaction codes.ootnotetextC. H. Still, this conference.^,ootnotetextD. J. Strozzi, E. A. Williams, D. E. Hinkel et al., Phys. Plasmas 15, 102703 (2008).^,ootnotetextR. L. Berger, C. H. Still, E. A. Williams, and A. B. Langdon, Phys. Plasmas 5, 4337 (1998); C. H. Still, R. L. Berger, A. B. Langdon, D. E. Hinkel, L. J. Suter, and E. A. Williams, Phys. Plasmas , 2023 (2000); D. E. Hinkel, D. A. Callahan, A. B. Langdon, S. H. Langer, C. H. Still, and E. A. Williams, Phys. Plasmas 15, 056314 (2008). These improved capabilities are being tested by making predictions for upcoming National Ignition Campaign experiments. Synthetic SRS spectra, reflectivity levels, and the angular distribution of SRS light will be compared to experimental results.

Hinkel, D. E.

2010-11-01

361

Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology  

SciTech Connect

This report, ''Summary Report of Laboratory Critical Experiment Analyses Performed for the Disposal Criticality Analysis Methodology'', contains a summary of the laboratory critical experiment (LCE) analyses used to support the validation of the disposal criticality analysis methodology. The objective of this report is to present a summary of the LCE analyses' results. These results demonstrate the ability of MCNP to accurately predict the critical multiplication factor (keff) for fuel with different configurations. Results from the LCE evaluations will support the development and validation of the criticality models used in the disposal criticality analysis methodology. These models and their validation have been discussed in the ''Disposal Criticality Analysis Methodology Topical Report'' (CRWMS M&O 1998a).

J. Scaglione

1999-09-09

362

A new direction in automated laboratory testing in Japan: five years of experience with total laboratory automation system management  

Microsoft Academic Search

The introduction of integrated laboratory systems has proceeded rapidly in Japan in these 15 years, but they require large initial investment for installation and do not always succeed in reducing laboratory cost. We also experienced three major events that taught us that total laboratory systems are not always effective: these were an earthquake, a nerve gas attack, and an outbreak

Noriyuki Tatsumi; Kiyoshi Okuda; Izumi Tsuda

1999-01-01

363

Seismoelectric and seismomagnetic measurements: original experiments within the Low Noise Underground Laboratory of Rustrel (France) (Invited)  

Microsoft Academic Search

Seismic wave propagation in fluid-filled porous materials induces electromagnetic effects due to relative pore-fluid motions. We present the original experimental apparatus built within the ultra-shielded chamber of the Low Noise Underground Laboratory of Rustrel (France) in order to detect the seismomagnetic couplings theoretically predicted by Pride (1994). This experiment included accelerometers, electric dipoles and induction magnetometers to characterize the seismo-electromagnetic

C. Bordes; L. Jouniaux; S. Garambois; M. Dietrich

2009-01-01

364

First Results from the XENON10 Dark Matter Experiment at the Gran Sasso National Laboratory  

Microsoft Academic Search

The XENON10 experiment at the Gran Sasso National Laboratory uses a 15 kg xenon dual phase time projection chamber to search for dark matter weakly interacting massive particles (WIMPs). The detector measures simultaneously the scintillation and the ionization produced by radiation in pure liquid xenon to discriminate signal from background down to 4.5 keV nuclear-recoil energy. A blind analysis of

J. Angle; E. Aprile; F. Arneodo; L. Baudis; A. Bernstein; A. Bolozdynya; P. Brusov; L. C. C. Coelho; C. E. Dahl; L. Deviveiros; A. D. Ferella; L. M. P. Fernandes; S. Fiorucci; R. J. Gaitskell; K. L. Giboni; R. Gomez; R. Hasty; L. Kastens; J. Kwong; J. A. M. Lopes; N. Madden; A. Manalaysay; A. Manzur; D. N. McKinsey; M. E. Monzani; K. Ni; U. Oberlack; J. Orboeck; G. Plante; R. Santorelli; J. M. F. Dos Santos; P. Shagin; T. Shutt; P. Sorensen; S. Schulte; C. Winant; M. Yamashita

2008-01-01

365

Intrinsic biodegradation of toluene coupled to the microbial reduction of ferric iron: laboratory column experiments  

Microsoft Academic Search

Intrinsic biodegradation of toluene coupled with the microbial reduction of ferric iron (Fe(III)) as the terminal electron acceptor was studied by using laboratory column experiments under continuous flow conditions. Columns were packed with contaminated aquifer sediment and N2-purged groundwater taken from the western part of the Gardermoen aquifer. The columns were operated anaerobically at 8 °C (in-situ temperature). Chloride was

Zuoping Zheng; Per Aagaard; Gijs D. Breedveld

2002-01-01

366

Sandia National Laboratories ASCOT (atmospheric studies in complex terrain) field experiment, September 1980  

SciTech Connect

During the period September 8 through September 25, 1980, Sandia National Laboratories, Division 4774, participated in a series of experiments held in the Geysers area of California. These experiments, aimed at providing data on nighttime drainage flow in complex terrain, were intended to provide a reliable basis for mathematical flow modeling. Tracers were released at several points on a valley rim and sampled by a large number of stations at ground level. Sandia's contribution was to make it possible to derive vertical tracer profiles. This was done by taking air samples from a captive balloon at chosen altitudes between the surface and 450 meters above ground.

Woods, R.O.

1982-04-01

367

A landmark recognition and tracking experiment for flight on the Shuttle/Advanced Technology Laboratory (ATL)  

NASA Technical Reports Server (NTRS)

The preliminary design of an experiment for landmark recognition and tracking from the Shuttle/Advanced Technology Laboratory is described. It makes use of parallel coherent optical processing to perform correlation tests between landmarks observed passively with a telescope and previously made holographic matched filters. The experimental equipment including the optics, the low power laser, the random access file of matched filters and the electro-optical readout device are described. A real time optically excited liquid crystal device is recommended for performing the input non-coherent optical to coherent optical interface function. A development program leading to a flight experiment in 1981 is outlined.

Welch, J. D.

1975-01-01

368

Cleaning oiled shores: laboratory experiments testing the potential use of vegetable oil biodiesels.  

PubMed

A series of laboratory experiments were carried out to test the potential of vegetable oil biodiesel for the cleaning of oiled shorelines. In batch experiments, biodiesel was shown to have a considerable capacity to dissolve crude oil, which appears to be dependent on the type of biodiesel used. Pure vegetable oil biodiesels (rapeseed and soybean) were significantly more effective in the cleanup of oiled sands (up to 96%) than recycled waste cooking oil biodiesel (70%). In microcosm and mesocosm experiments, oiled sediments were sprayed with biodiesel and subjected to simulated tides. Microcosm experiments revealed that, of those tested, the highest ratio of biodiesel to crude oil, had the highest effectiveness for cleaning fine sands, with ratios of 2:1 (biodiesel:crude oil) giving the best results. In the mesocosm experiments a ratio 1:1 of soybean biodiesel to crude oil removed 80% of the oil in cobbles and fine sands, 50% in coarse sand and 30% in gravel. Most of the oil was removed with the surface water, with only a small amount being flushed through the sediments. Particle size and pore size were important determinants in the cleanup and mobility of crude oil in the sediments in these static systems. It is expected that the biodiesel effectiveness should improve in the natural environment particularly in exposed beaches with strong wave action. However, more laboratory and field trials are required to confirm the operational use of biodiesel as a shoreline cleaner. PMID:14575742

Pereira, M Glória; Mudge, Stephen M

2004-01-01

369

Technical Report of National Aerospace Laboratory: Design and Development of the Hypersonic Flight Experiment (HYFLEX) Vehicle.  

National Technical Information Service (NTIS)

The Hypersonic Flight Experiment (HYFLEX) was conducted in February 1996 as Japan's first bypersonic flight of a lifting vehicle with the basic characteristics of a reentry vehicle. This paper describes details of the final design of the vehicle sub-syste...

2003-01-01

370

One, Two, and Three Dimensional Simulations of Laboratory Beam-Injection Experiments  

NASA Astrophysics Data System (ADS)

We present the results of three-dimensional fully kinetic simulations of UCLA laboratory experiments,(A. Y. Wong and P. Y. Cheung, Phys. Rev. Lett.), 52, 1222 (1984) which were the first experiments to show Langmuir-wave collapse in a beam-driven plasma. Our massively-parallel particle-in-cell (PIC) simulations model the continuous injection of a fast (v_b=20v_e), cold (? vb = ? v_e), and weak (n_b/n_0=0.005) beam, which is comparable to that used in the laboratory experiments. By comparing the results of 1-D, 2-D, and 3-D simulations with one another and with laboratory measurements, we address the role of dimensionality on key phases of the evolution of beam-driven Langmuir turbulence. Of particular interest are the localization of intense Langmuir wave packets and the subsequent deepening of quasineutral density depressions due to the hydrodynamic response of ions to the ponderomotive force of the localized Langmuir waves. A variety of visualization tools will be employed in the analysis of the three-dimensional turbulence.

Goldman, M. V.; Newman, D. L.; Oppenheim, M. M.; Wong, A. Y.; Cheung, P. Y.

2000-10-01

371

MIT Lincoln LaboratoryHTS: MTI-UAV Cueing Experiment LAB/RAK 1/24/2006  

E-print Network

MIT Lincoln LaboratoryHTS: MTI-UAV Cueing Experiment LAB/RAK 1/24/2006 Lawrence Bush 2006 January 24 Semi-Automated Cueing of Predator UAV Operators from RADAR Moving Target (MTI) Data MIT Lincoln and are not necessarily endorsed by the United States Government. #12;MIT Lincoln LaboratoryHTS: MTI-UAV Cueing Experiment

Cummings, Mary "Missy"

372

Incrementally Approaching an Inquiry Lab Curriculum: Can Changing a Single Laboratory Experiment Improve Student Performance in General Chemistry?  

ERIC Educational Resources Information Center

Many institutions are responding to current research about how students learn science by transforming their general chemistry laboratory curricula to be inquiry-oriented. We present a comparison study of student performance after completing either a traditional or an inquiry stoichiometry experiment. This single laboratory experience was the only…

Cacciatore, Kristen L.; Sevian, Hannah

2009-01-01

373

The Challenges of Blending a Face-to-Face Laboratory Experience with a Televised Distance Education Course  

ERIC Educational Resources Information Center

This article describes the practical challenges faced by instructors who must blend a face-to-face laboratory experience into a distance education course. This issue is discussed in the context of an ongoing kinesiology and health course that includes a mandatory physical activity laboratory experience. The challenges that have arisen around this…

LeDrew, June; Cummings-Vickaryous, Bonnie

2010-01-01

374

Laboratory experiment to measure 5-MHz volume backscattering strengths from Red-tide causing microalgae Chattonella antiqua  

NASA Astrophysics Data System (ADS)

An acoustic laboratory experiment using 5-MHz signals was conducted to measure the volume backscattering strengths of red-tide causing microalgae, Chattonella antiqua, which is one of the species of harmful algal blooms in the coastal waters of Korea and Japan. The measured backscattering strengths increased with cell abundance, with a slope of approximately 10 dB per decade increase in cell numbers. The density and sound speed ratios of the Chattonella cell to the water medium were estimated via the density gradient centrifugation method and the time-travel difference method, respectively. Finally, the measured backscattering strengths were compared to those predicted by a fluid-sphere scattering model, in which the estimated sound speed and density contrasts were used as input parameters.

Kim, Junghun; Choi, Jee Woong; Kang, Donhyug

2012-09-01

375

Assessment of the predictive capabilities of stochastic theories in a three-dimensional laboratory test aquifer: Effective hydraulic conductivity and temporal moments of breakthrough curves  

NASA Astrophysics Data System (ADS)

Conservative and sorptive tracer experiments were conducted in a highly heterogeneous (?lnK2 = 1.79) and anisotropic (?H/?V = 3.52) three-dimensional test aquifer under well-controlled laboratory conditions to evaluate the effective conductivity and temporal moments predicted by stochastic theories. The spatial distribution of lnK in the test aquifer conformed to a statistically homogeneous system, thus allowing evaluation of results from stochastic theories for stationary random fields. Effective hydraulic conductivity Keff in the mean flow direction for the test aquifer was compared with different stochastic theoretical expressions. Breakthrough curves (BTCs) at individual deep-penetrating observation wells and averaged breakthrough curves at control planes were examined. The mean arrival time and the travel time variance estimated using averaged BTCs from many observation wells at the same control plane for bromide and lithium were slightly overestimated by stochastic theories, yet most of the experimental data ranged within the confidence interval rendered by the uncertainty in the statistical properties of the test aquifer. A highlight of our experimental approach is that the continuous sampling procedure also permitted the evaluation of higher-order temporal moments that were analyzed to study the asymmetry and peakedness of BTCs by means of the coefficients of skewness and kurtosis, respectively. Small-perturbation analytical solutions for the coefficient of skewness and kurtosis were provided. It is seen that although stochastic theories based upon small perturbations provide reasonably good estimates of the coefficients of skewness and kurtosis associated with averaged BTCs at control planes, in general, they can largely underestimate the peakedness and tailing of BTCs observed at individual deep-penetrating observation wells.

Fernàndez-Garcia, Daniel; Rajaram, Harihar; Illangasekare, Tissa H.

2005-04-01

376

Laboratory and Field Experiments on Expulsion of Selected Ions along Divergent Polar Geomagnetic Fields  

NASA Astrophysics Data System (ADS)

Laboratory and Field Experiments on Expulsion of Selected Ions along Divergent Polar Geomagnetic Fields. Laboratory experiments have shown significant gyro-resonance acceleration of minority ion species in a magnetized plasma. Field aligned elctron drifts can provide free energy needed to make this process efficient. The linear magnetized device has a uniform magnetic field linked to two adjustable mirrors at the ends. Outdoor experiments at HIPAS Facility Ak(1) ( 84 MW ERP ) are used to test this process in the earth's "chimneys" at the two poles. The divergent polar geomagnetic field converts the perpendicular ion velocity into an upward motion. Satellites and ground-based ELF receivers,supplemented by UHF radars, LIDARs and infrared diagnostics , will monitor low-frequency EM waves and upflows of ions. The upward transport of ions in the lower atmosphere by field-induced diffusion and convection and the coupling to the free energy in the auroral region will be discussed. Computer modeling and theoeries complement our experiments. 1. Wong, A.Y. et al. AIP CIP 96-27719, Chap 3, pp 41-75, 1997

Wong, A. Y.; Deng, B.; Quon, B.; Wang, R.; Hartzell, J.; Rosenthal, G.; Hazelton, L. R.

2007-12-01

377

Safety analysis report for the Hanford Critical Mass Laboratory: Supplement No. 2. Experiments with heterogeneous assemblies  

SciTech Connect

Factors affecting the safety of criticality experiments using heterogeneous assemblies are described and assessed. It is concluded that there is no substantial change in safety from experiments already being routinely performed at the Critical Mass Laboratory (CML), and that laboratory and personnel safety are adequately provided by the combination of engineered and administrative safety limits enforced at the CML. This conclusion is based on the analysis of operational controls, potential hazards, and the consequences of accidents. Contingencies considered that could affect nuclear criticality include manual changes in fuel loadings, water flooding, fire, explosion, loss of services, earthquake, windstorm, and flood. Other potential hazards considered include radiation exposure to personnel, and potential releases within the Assembly Room and outside to the environment. It is concluded that the Maximum Credible Nuclear Burst of 3 x 10/sup 18/ fissions (which served as the design basis for the CML) is valid for heterogeneous assemblies as well as homogeneous assemblies. This is based upon examination of the results of reactor destructive tests and the results of the SL-1 reactor destructive accident. The production of blast effects which might jeopardize the CML critical assembly room (of thick reinforced concrete) is not considered credible due to the extreme circumstances required to produce blast effects in reactor destructive tests. Consequently, it is concluded that, for experiments with heterogeneous assemblies, the consequences of the Maximum Credible Burst are unchanged from those previously estimated for experiments with homogeneous systems.

Gore, B.F.; Davenport, L.C.

1981-04-01

378

Fundamental processes in the expansion, energization, and coupling of single- and multi-Ion plasmas in space: Laboratory simulation experiments  

NASA Technical Reports Server (NTRS)

We have conducted a laboratory investigation into the physics of plasma expansions and their associated energization processes. We studied single- and multi-ion plasma processes in self-expansions, and included light and heavy ions and heavy/light mixtures to encompass the phenomenological regimes of the solar and polar winds and the AMPTE and CRRES chemical release programs. The laboratory experiments provided spatially-distributed time-dependent measurements of total plasma density, temperature, and density fluctuation power spectra with the data confirming the long-theorized electron energization process in an expanding cloud - a result that was impossible to determine in spaceborne experiments (as e.g., in the CRRES program). These results provided the missing link in previous laboratory and spaceborne programs. confirming important elements in our understanding of such solar-terrestrial processes as manifested in expanding plasmas in the solar wind (e.g., CMES) and in ionospheric outflow in plasmaspheric fluctuate refilling after a storm. The energization signatures were seen in an entire series of runs that varied the ion species (Ar', Xe', Kr' and Ne'), and correlative studies included spectral analyses of electrostatic waves collocated with the energized electron distributions. In all cases wave energies were most intense during the times in which the suprathermal populations were present, with wave intensity increasing with the intensity of the suprathermal electron population. This is consistent with theoretical expectations wherein the energization process is directly attributable to wave particle interactions. No resonance conditions were observed, in an overall framework in which the general wave characteristics were broadband with power decreasing with increasing frequency.

Szuszczewicz, E. P.; Bateman, T. T.

1996-01-01

379

The Role of Laboratory Experiments in the Design of the Field Trial of CO2 Exchange in Methane Hydrates  

NASA Astrophysics Data System (ADS)

The recent field trial at the Ignik Sikumi #1 well on the North Slope of Alaska of the CO2 exchange for CH4 in natural gas hydrates was successful in large part due to the extensive planning of the operation that accounted for a wide range of contingencies. Much of the planning was directed by specific laboratory tests of the CO2 exchange mechanism under reservoir conditions. The original laboratory tests of the CO2 exchange process were conducted under idealized conditions of partial initial water saturations, a pure CO2 stream and P-T conditions well into the methane hydrate stability field. The more recent experiments evaluated the role of excess water in the hydrate-saturated sands and the effectiveness of various CO2/N2 gas mixtures in driving the exchange process. There was concern over injecting a hydrate former into a sand interval filled with reactive water that would result in additional hydrate formation at the well face. Since it was not possible to use a pure stream of liquid CO2, gas mixtures provided a solution to the injectivity issue. The laboratory tests demonstrated that the gas mixtures maintained and sometimes enhanced the permeability of the hydrate-saturated sand pack without significant dissociation of the original hydrate. The tests also indicated that the gas mixtures were as efficient and fast in exchanging CO2 for CH4 in the hydrate structure as was the original pure liquid CO2 stream. The experiments with a fiber-optic temperature sensor down the length of the sand pack demonstrated the local nature of the initial hydrate formation and exchange process.

Howard, J. J.; Hester, K. C.; Stevens, J.

2012-12-01

380

Effective population size may limit the power of laboratory experiments to demonstrate sympatric and parapatric speciation.  

PubMed Central

Laboratory experiments designed to elucidate the mechanisms of sympatric and parapatric speciation may have been handicapped by too small population sizes, although this possibility has seldom been discussed. In this paper we review the published records of sympatric and parapatric speciation experiments to test the relative importance of selection intensity applied, duration of experiment and effective population size. Our results show that among these factors only effective population size has had a general effect on the generation of assortative mating. Reduced interbreeding is less likely to develop in small populations where the selection process often seems to have been opposed by inbreeding depression or loss of genetic variation. This study demonstrates that the experimental evidence frequently used as an argument against sympatric and parapatric speciation models is not as strong as previously believed. PMID:10787165

Odeen, A; Florin, A B

2000-01-01

381

Persistence and partitioning of eight selected pharmaceuticals in the aquatic environment: laboratory photolysis, biodegradation, and sorption experiments.  

PubMed

We selected eight pharmaceuticals with relatively high potential ecological risk and high consumption-namely, acetaminophen, atenolol, carbamazepine, ibuprofen, ifenprodil, indomethacin, mefenamic acid, and propranolol-and conducted laboratory experiments to examine the persistence and partitioning of these compounds in the aquatic environment. In the results of batch sunlight photolysis experiments, three out of eight pharmaceuticals-propranolol, indomethacin, and ifenprodil-were relatively easily photodegraded (i.e., half-life<24h), whereas the other five pharmaceuticals were relatively stable against sunlight. The results of batch biodegradation experiments using river water suggested relatively slow biodegradation (i.e., half-life>24h) for all eight pharmaceuticals, but the rate constant was dependent on sampling site and time. Batch sorption experiments were also conducted to determine the sorption coefficients to river sediments and a model soil sample. The determined coefficients (K(d) values) were much higher for three amines (atenolol, ifenprodil, and propranolol) than for neutral compounds or carboxylic acids; the K(d) values of the amines were comparable to those of a four-ring polycyclic aromatic hydrocarbon (PAH) pyrene. The coefficients were also higher for sediment/soil with higher organic content, and the organic carbon-based sorption coefficient (logK(oc)) showed a poor linear correlation with the octanol-water distribution coefficient (logD(ow)) at neutral pH. These results suggest other sorption mechanisms-such as electrochemical affinity, in addition to hydrophobic interaction-play an important role in sorption to sediment/soil at neutral pH. PMID:19041113

Yamamoto, Hiroshi; Nakamura, Yudai; Moriguchi, Shigemi; Nakamura, Yuki; Honda, Yuta; Tamura, Ikumi; Hirata, Yoshiko; Hayashi, Akihide; Sekizawa, Jun

2009-02-01

382

Fault healing promotes high-frequency earthquakes in laboratory experiments and on natural faults.  

PubMed

Faults strengthen or heal with time in stationary contact, and this healing may be an essential ingredient for the generation of earthquakes. In the laboratory, healing is thought to be the result of thermally activated mechanisms that weld together micrometre-sized asperity contacts on the fault surface, but the relationship between laboratory measures of fault healing and the seismically observable properties of earthquakes is at present not well defined. Here we report on laboratory experiments and seismological observations that show how the spectral properties of earthquakes vary as a function of fault healing time. In the laboratory, we find that increased healing causes a disproportionately large amount of high-frequency seismic radiation to be produced during fault rupture. We observe a similar connection between earthquake spectra and recurrence time for repeating earthquake sequences on natural faults. Healing rates depend on pressure, temperature and mineralogy, so the connection between seismicity and healing may help to explain recent observations of large megathrust earthquakes which indicate that energetic, high-frequency seismic radiation originates from locations that are distinct from the geodetically inferred locations of large-amplitude fault slip. PMID:23128232

McLaskey, Gregory C; Thomas, Amanda M; Glaser, Steven D; Nadeau, Robert M

2012-11-01

383

Fault healing promotes high-frequency earthquakes in laboratory experiments and on natural faults  

USGS Publications Warehouse

Faults strengthen or heal with time in stationary contact and this healing may be an essential ingredient for the generation of earthquakes. In the laboratory, healing is thought to be the result of thermally activated mechanisms that weld together micrometre-sized asperity contacts on the fault surface, but the relationship between laboratory measures of fault healing and the seismically observable properties of earthquakes is at present not well defined. Here we report on laboratory experiments and seismological observations that show how the spectral properties of earthquakes vary as a function of fault healing time. In the laboratory, we find that increased healing causes a disproportionately large amount of high-frequency seismic radiation to be produced during fault rupture. We observe a similar connection between earthquake spectra and recurrence time for repeating earthquake sequences on natural faults. Healing rates depend on pressure, temperature and mineralogy, so the connection between seismicity and healing may help to explain recent observations of large megathrust earthquakes which indicate that energetic, high-frequency seismic radiation originates from locations that are distinct from the geodetically inferred locations of large-amplitude fault slip

McLaskey, Gregory C.; Thomas, Amanda M.; Glaser, Steven D.; Nadeau, Robert M.

2012-01-01

384

Seismic monitoring of CO2 plumes in deep saline aquifers: results from laboratory experiments  

NASA Astrophysics Data System (ADS)

Geophysical monitoring of geological CO2 sequestration is required to track the location of the CO2 plume, to verify the injected mass, to assess the integrity of the cap rock and to ensure that the wells are not leaking. Any geophysical monitoring program will certainly comprise seismic methods, e. g. surface seismics, crosshole, or VSP. These methods have proved to render useful information where fluid substitution processes are involved, e. g. in enhanced oil recovery projects. The large contrast in density and bulk modulus between brine and CO2 (gaseous or supercritical) makes it possible to detect the CO2 plume in deep saline aquifers, which was successfully shown during the injection of CO2 into the Utsira formation as part of the Sleipner Project (Torp & Gale, 2004). In order to further characterize the CO2 plume, e. g. with respect to local variations of the CO2 saturation, the geophysical "signature" of different saturation and pressure states have to be established through measurements on representative reservoir rocks. As a first step we conducted laboratory measurements of seismic properties at full brine and full CO2 saturation, respectively, on a set of 5 sandstone samples from outcrops in Germany. The samples cover a porosity range from 14 % to 22%. The experiments were conducted in a triaxial cell at pressures and temperatures that are representative for deep saline aquifers. We found that the seismic velocities are clearly affected by the saturation state. The magnitude of the fluid substitution effect on vp depends on the porosity: the higher the porosity the higher the velocity change. The compressional wave velocity decreases typically by -5 % to -10 % when brine is displaced by CO2 within the porosity range of our samples. This can be explained by a decrease of the effective bulk modulus of the saturated rock (Gassmann, 1951). A further analysis of the velocity data indicates that the displacement process is incomplete; i. e. a residual brine saturation of approximately 10 % to 30 % is left in the sample. The inverse scenario (brine displacing CO2), in contrast, leads to an almost complete fluid substitution. These effects reflect probably the stability of the advancing interface between the fluids which depends on their viscosity ratio. The shear wave velocity increases typically by 1 % to 2 % when CO2 displaces brine. This can be interpreted as density effect, while the shear modulus is nearly independent of the saturand (Gassmann, 1951). The seismic wave attenuation, particularly the ratio Qp/Qs, is highly sensitive to the saturation state: the ratio changes as much as -20 % to -80 %. Although attenuation data are more difficult to derive from field measurements than velocity data, the attenuation may be useful as additional seismic attribute for plume characterization. References Gassmann, F. (1951): Ueber die Elastizitaet poroeser Medien, Vierteljahrsschrift der Naturforschenden Gesellschaft Zuerich, vol. 96, 1-23 Torp, T., J. Gale (2004): Demonstrating storage of CO2 in geologic reservoirs: The Sleipner and SACS projects, Energy, 29, 1361-1369

Schuett, H.; Wigand, M.; Spangenberg, E.; Borm, G.

2005-12-01

385

Los Alamos National Laboratory: A guide to records series supporting epidemiologic studies conducted for the Department of Energy  

SciTech Connect

The purpose of this guide is to describe each series of records that pertains to the epidemiologic studies conducted by the Epidemiology Section of the Occupational Medicine Group (ESH-2) at the Department of Energy`s (DOE) Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico. The records described in this guide relate to occupational studies performed by the Epidemiology Section, including those pertaining to workers at LANL, Mound Plant, Oak Ridge Reservation, Pantex Plant, Rocky Flats Plant, and Savannah River Site. Also included are descriptions of other health-related records generated or collected by the Epidemiology Section and a small set of records collected by the Industrial Hygiene and Safety Group. This guide is not designed to describe the universe of records generated by LANL which may be used for epidemiologic studies of the LANL work force. History Associates Incorporated (HAI) prepared this guide as part of its work as the support services contractor for DOE`s Epidemiologic Records Inventory Project. This introduction briefly describes the Epidemiologic Records Inventory Project, HAI`s role in the project, the history of LANL the history and functions of LANL`s Health Division and Epidemiology Section, and the various epidemiologic studies performed by the Epidemiology Section. It provides information on the methodology that HAI used to inventory and describe records housed in the offices of the LANL Epidemiology Section in Technical Area 59 and at the LANL Records Center. Other topics include the methodology used to produce the guide, the arrangement of the detailed record series descriptions, and information concerning access to records repositories.

NONE

1997-01-01

386

Zero-Gravity Atmospheric Cloud Physics Experiment Laboratory engineering concepts/design tradeoffs. Volume 1: Study results  

NASA Technical Reports Server (NTRS)

The work is summarized which was accomplished from January 1974 to October 1974 for the Zero-Gravity Atmospheric Cloud Physics Laboratory. The definition and development of an atmospheric cloud physics laboratory and the selection and delineation of candidate experiments that require the unique environment of zero gravity or near zero gravity are reported. The experiment program and the laboratory concept for a Spacelab payload to perform cloud microphysics research are defined. This multimission laboratory is planned to be available to the entire scientific community to utilize in furthering the basic understanding of cloud microphysical processes and phenomenon, thereby contributing to improved weather prediction and ultimately to provide beneficial weather control and modification.

Greco, R. V.; Eaton, L. R.; Wilkinson, H. C.

1974-01-01

387

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation  

NASA Astrophysics Data System (ADS)

Spatial variation of nonlinear wave groups with different initial envelope shapes is theoretically studied first, confirming that the simplest nonlinear theoretical model is capable of describing the evolution of propagating wave packets in deep water. Moreover, three groups of laboratory experiments run in the wave basin of CEHIPAR (Canal de Experiencias Hidrodinámicas de El Pardo, known also as El Pardo Model Basin) was founded in 1928 by the Spanish Navy. are systematically compared with the numerical simulations of the nonlinear Schrödinger equation. Although a little overestimation is detected, especially in the set of experiments characterized by higher initial wave steepness, the numerical simulation still displays a high degree of agreement with the laboratory experiments. Therefore, the nonlinear Schrödinger equation catches the essential characteristics of the extreme waves and provides an important physical insight into their generation. The modulation instability, resulting from the quasi-resonant four-wave interaction in a unidirectional sea state, can be indicated by the coefficient of kurtosis, which shows an appreciable correlation with the extreme wave height and hence is used in the modified Edgeworth-Rayleigh distribution. Finally, some statistical properties on the maximum wave heights in different sea states have been related with the initial Benjamin-Feir index.

Zhang, H. D.; Guedes Soares, C.; Cherneva, Z.; Onorato, M.

2014-04-01

388

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation  

NASA Astrophysics Data System (ADS)

Spatial variation of nonlinear wave groups with different initial envelope shapes is theoretically studied first, confirming that the simplest nonlinear theoretical model is capable of describing the evolution of propagating wave packets in deep water. Moreover, three groups of laboratory experiments run in the wave basin of CEHIPAR are systematically compared with the numerical simulations of the nonlinear Schrödinger equation. Although a small overestimation is detected, especially in the set of experiments characterized by higher initial wave steepness, the numerical simulations still display a high degree of agreement with the laboratory experiments. Therefore, the nonlinear Schrödinger equation catches the essential characteristics of the extreme waves and provides an important physical insight into their generation. The modulation instability, resulted by the quasi-resonant four wave interaction in a unidirectional sea state, can be indicated by the coefficient of kurtosis, which shows an appreciable correlation with the extreme wave height and hence is used in the modified Edgeworth-Rayleigh distribution. Finally, some statistical properties on the maximum wave heights in different sea states have been related with the initial Benjamin-Feir Index.

name prefix surname suffix, given; Zhang, H. D.; Guedes Soares, C.; Cherneva, Z.; Onorato, M.

2013-10-01

389

An analysis of high school students' perceptions and academic performance in laboratory experiences  

NASA Astrophysics Data System (ADS)

This research study is an investigation of student-laboratory (i.e., lab) learning based on students' perceptions of experiences using questionnaire data and evidence of their science-laboratory performance based on paper-and-pencil assessments using Maryland-mandated criteria, Montgomery County Public Schools (MCPS) criteria, and published laboratory questions. A 20-item questionnaire consisting of 18 Likert-scale items and 2 open-ended items that addressed what students liked most and least about lab was administered to students before labs were observed. A pre-test and post-test assessing laboratory achievement were administered before and after the laboratory experiences. The three labs observed were: soda distillation, stoichiometry, and separation of a mixture. Five significant results or correlations were found. For soda distillation, there were two positive correlations. Student preference for analyzing data was positively correlated with achievement on the data analysis dimension of the lab rubric. A student preference for using numbers and graphs to analyze data was positively correlated with achievement on the analysis dimension of the lab rubric. For the separating a mixture lab data the following pairs of correlations were significant. Student preference for doing chemistry labs where numbers and graphs were used to analyze data had a positive correlation with writing a correctly worded hypothesis. Student responses that lab experiences help them learn science positively correlated with achievement on the data dimension of the lab rubric. The only negative correlation found related to the first result where students' preference for computers was inversely correlated to their performance on analyzing data on their lab report. Other findings included the following: students like actual experimental work most and the write-up and analysis of a lab the least. It is recommended that lab science instruction be inquiry-based, hands-on, and that students be tested for lab content acquisition. The final conclusion of the study is that students expressed a preference for working in groups and working with materials and equipment as opposed to individual, non-group work and analyzing data.

Mirchin, Robert Douglas

390

Deciphering transmissivity and hydraulic conductivity of the aquifer by vertical electrical sounding (VES) experiments in Northwest Bangladesh  

NASA Astrophysics Data System (ADS)

The vertical electrical soundings (VESs) are carried out in 24 selective locations of Chapai-Nawabganj area of northwest Bangladesh to determine the transmissivity and hydraulic conductivity of the aquifer. Initially, the transmissivity and hydraulic conductivity are determined from the pumping data of nearby available production wells. Afterwards, the T and K are correlated with geoelectrical resistance and the total resistivity of the aquifer. The present study deciphers the functional analogous relations of the geoelectrical resistance with the transmissivity and the total resistivity with the hydraulic conductivity of the aquifer in northwest Bangladesh. It has been shown that the given equations provide reasonable values of transmissivity and hydraulic conductivity where pumping test information is unavailable. It can be expected that the aquifer properties viz. transmissivity and hydraulic conductivity of geologically similar area can be determined with the help of the obtained equations by conducting VES experiments.

Sattar, Golam Shabbir; Keramat, Mumnunul; Shahid, Shamsuddin

2014-06-01

391

UV Radiation: a new first year physics/life sciences laboratory experiment  

NASA Astrophysics Data System (ADS)

Unfortunately, Australia leads the world in the number of skin cancer cases per capita. Three major factors that contribute to this are: 1) the level of damaging ultraviolet (UV) radiation in Australia is higher than in many other countries. This is caused, among other factors, by the stratospheric ozone depletion and Antarctic ozone hole; 2) many people in Australia are of Irish-Scottish origin and their skin can not repair the damage caused by the UV radiation as effectively as the skin of people of other origins; 3) Australia is one of the world’s leaders in the outdoor activities where people tend to spend more time outside. As our experience has shown, most Australian University students, high school students, and even high school teachers were largely unaware of the UV damage details and effective safety measures. Therefore, a need for new ways to educate people became apparent. The general aim of this new 1st year laboratory experiment, developed and first offered at La Trobe University (Melbourne, Australia) in 2009, is to investigate how UV-B radiation levels change under various solar illumination conditions and how effective different types of protection are. After pre-lab readings on physical concepts and biological effects of UV radiation, and after solving all pre-lab problems, the students go outside and measure the actual change in UV-B and UV-A radiation levels under various conditions. Some of these conditions are: direct sun, shade from a building, shade under the roof, reflection from various surfaces, direct sun through cheap and expensive sunglasses and eyeglasses, direct sun through various types of cloth and hair. The equipment used is the UV-Probe manufactured by sglux SolGel Technologies GmbH. The students’ feedback on this new laboratory experiment was very positive. It was ranked top among all physics experiments offered as part of that subject (Physics for Life Sciences) in 2009 and top among all physics experiments presented for peer evaluation at the Advanced Science Education Learning Laboratory Workshop in April 2010 at the University of Adelaide, Australia. All three main components of the UV Radiation experiment - pre-lab exercises, taking measurements, and a group discussion led by a demonstrator, were assessed by the students and by the teaching academics as a very important and valuable contribution to learning.

Petelina, S. V.; Siddaway, J. M.

2010-12-01

392

Energy supply and environmental issues: The Los Alamos National Laboratory experience in regional and international programs  

SciTech Connect

The Los Alamos National Laboratory, operated by the University of California, encompasses more than forty-three square miles of mesas and canyons in northern New Mexico. A Department of Energy national laboratory, Los Alamos is one of the largest multidisciplinary, multiprogram laboratories in the world. Our mission, to apply science and engineering capabilities to problems of national security, has expanded to include a broad array of programs. We conduct extensive research in energy, nuclear safeguards and security, biomedical science, computational science, environmental protection and cleanup, materials science, and other basic sciences. The Energy Technology Programs Office is responsible for overseeing and developing programs in three strategic areas: energy systems and the environment, transportation and infrastructure, and integrated chemicals and materials processing. Our programs focus on developing reliable, economic and environmentally sound technologies that can help ensure an adequate supply of energy for the nation. To meet these needs, we are involved in programs that range from new and enhanced oil recovery technologies and tapping renewable energy sources, through efforts in industrial processes, electric power systems, clean coal technologies, civilian radioactive waste, high temperature superconductivity, to studying the environmental effects of energy use.

Goff, S.J.

1995-12-31

393

Developing a theory of clinical instructor identity using the experiences of medical laboratory science practitioners.  

PubMed

This study investigated medical laboratory science clinical instructors' beliefs about teaching and how they viewed themselves as teachers. The first phase of the study included an integrative literature review, which suggested that the development of teacher identity in school-based educators, and to a lesser extent higher education faculty, is dependent on four dimensions: personal factors, training factors, contextual factors, and reflective practice. The second phase of this study began qualitative inquiry into the ways that these participants described their teaching and professional identity. Interviews were conducted with medical laboratory science clinical instructors in order to gain an understanding of their perceptions of themselves as teachers. The data collected in this study indicate that this group of clinical instructors saw themselves as teachers who were responsible for providing students with technical skills needed to become competent practitioners and the theoretical foundation necessary to pass the national certification exam. The study participants also saw themselves as mentors who were responsible for passing along professional knowledge to the next generation of laboratory practitioners. During data analysis three themes emerged that represent aspects of teacher identity in clinical instructors: belief in one's teaching ability, desire to expand one's professional responsibilities, and reflection on one's teaching. The findings from this study may provide a foundation for future research designed to measure teacher identity in clinical instructors. PMID:25000652

Miller, Wendy

2014-01-01

394

A Convenient Synthesis of the Tetrasubstituted Pyrrole: An Undergraduate Heterocyclic Laboratory Experiment  

NASA Astrophysics Data System (ADS)

A two-step synthesis of tetrasubstituted pyrroles from esters of a-amino acids has been applied as a simple undergraduate laboratory experiment, which illustrates the utility of amino acids in heterocyclic synthesis. The enamine, prepared by an addition of L-phenylalanine ethyl ester to dimethyl acetylenedicarboxylate was cyclized in presence of sodium methoxide in methanol giving 5-benzyl-4-hydroxy-2,3-di(methoxycarbonyl)pyrrole in 63-72 % yield. The procedure represents an alternative to classical pyrrole syntheses which are usually included in practical undergraduate organic chemistry.

Kolar, Patrik; Tisler, Miha

1996-10-01

395

Laboratory Experiments of Surface Roughness Effect in X-ray Fluorescence at Planetary Regolith  

NASA Astrophysics Data System (ADS)

Laboratory experiments were performed to investigate roughness effect in X-ray fluorescence (XRF) for interpreting remote X-ray spectrometry. To simulate microscopic roughness of uppermost planetary regolith, powdery specimens crashed rocks ranging 25 to 500 microns in size and flat rock plates for comparison were used. The results show XRF intensities from powdery specimens decrease relative to those from flat plates by up to 50 % for larger particle size and at increasing source-to-surface-to-detector (phase) angle. Corrections should be needed for elemental analysis by remote XRF spectrometry. This study is based on our previous results in Maruyama et al, (2008).

Okada, T.

2010-03-01

396

The effect of pre-existing vulnerability factors on a laboratory analogue trauma experience.  

PubMed

This study examined how pre-existing emotional and personality vulnerability factors affect responses to an analogue trauma experience. Sixty-eight undergraduate participants viewed a distressing film and completed measures of trait anxiety, intelligence, depression, trait dissociation, as well as changes in state anxiety, then recorded intrusions over the following week. Results revealed that trait anxiety, depression, trait dissociation, change in anxiety, and post-state anxiety were associated with intrusion frequency. Post-state anxiety mediated the relationship between trait anxiety, depression and trait dissociation, and intrusions. Implications for PTSD theories and laboratory trauma analogue research examining specific elements of cognitive models of PTSD are discussed. PMID:18294615

Laposa, Judith M; Alden, Lynn E

2008-12-01

397

Resource Letter SPE-1: Single-Photon Experiments in the Undergraduate Laboratory  

NASA Astrophysics Data System (ADS)

This Resource Letter lists undergraduate-laboratory adaptations of landmark optical experiments on the fundamentals of quantum physics. Journal articles and websites give technical details of the adaptations, which offer students unique hands-on access to testing fundamental concepts and predictions of quantum mechanics. A selection of the original research articles that led to the implementations is included. These developments have motivated a rethinking of the way quantum mechanics is taught, so this Resource Letter also lists textbooks that provide these new approaches.

Galvez, Enrique J.

2014-11-01

398

Estimated Uncertainties in the Idaho National Laboratory Matched-Index-of-Refraction Lower Plenum Experiment  

SciTech Connect

The purpose of the fluid dynamics experiments in the MIR (Matched-Index-of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for typical Very High Temperature Reactor (VHTR) plenum geometries in the limiting case of negligible buoyancy and constant fluid properties. The experiments use optical techniques, primarily particle image velocimetry (PIV) in the INL MIR flow system. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in passages and around objects to be obtained without locating a disturbing transducer in the flow field and without distortion of the optical paths. The objective of the present report is to develop understanding of the magnitudes of experimental uncertainties in the results to be obtained in such experiments. Unheated MIR experiments are first steps when the geometry is complicated. One does not want to use a computational technique, which will not even handle constant properties properly. This report addresses the general background, requirements for benchmark databases, estimation of experimental uncertainties in mean velocities and turbulence quantities, the MIR experiment, PIV uncertainties, positioning uncertainties, and other contributing measurement uncertainties.

Donald M. McEligot; Hugh M. McIlroy, Jr.; Ryan C. Johnson

2007-11-01

399

Child Impulsiveness—Inattention, Early Peer Experiences, and the Development of Early Onset Conduct Problems  

Microsoft Academic Search

The conjoint influence of child Impulsiveness—Inattention (I\\/I) and peer relationships on growth trajectories of conduct problems was assessed in a community sample of 267 boys and girls. I\\/I reliably predicted teacher- and parent-reported conduct problems at kindergarten entry and growth in those problems over the next 2 years for boys and girls. The relation of boys' I\\/I to conduct problems

James Snyder; Joy Prichard; Lynn Schrepferman; M. Renee Patrick; Mike Stoolmiller

2004-01-01

400

Early Experience with Racial Discrimination and Conduct Disorder as Predictors of Subsequent Drug Use: A Critical Period Hypothesis  

PubMed Central

A critical period hypothesis linking early experiences with both racial discrimination and conduct disorder (CD) with subsequent drug use was examined in a panel of 889 African American adolescents (age 10.5 at Time 1) and their parents. Analyses indicated that these early experiences did predict use by the adolescents at Time 3--five years later. These relations were both direct and indirect, being mediated by an increase in affiliation with friends who were using drugs. The relations existed controlling for parents’ reports of their use, discrimination experiences, and their socioeconomic status (SES). The impact of these early experiences on African American families is discussed. PMID:17275213

Gibbons, Frederick X.; Yeh, Hsiu-Chen; Gerrard, Meg; Cleveland, Michael J.; Cutrona, Carolyn; Simons, Ronald L.; Brody, Gene H.

2007-01-01

401

Students' Design of Experiments: An Inquiry Module on the Conduction of Heat  

ERIC Educational Resources Information Center

This article examines secondary students' design of experiments after engagement in an innovative and inquiry-oriented module on heat transfer. The module consists of an integration of hands-on experiments, simulated experiments and microscopic model simulations, includes a structured series of guided investigative tasks and was implemented for a…

Hatzikraniotis, E.; Kallery, M.; Molohidis, A.; Psillos, D.

2010-01-01

402

Acoustic impulse response method as a source of undergraduate research projects and advanced laboratory experiments.  

PubMed

A straightforward and inexpensive implementation of acoustic impulse response measurement is described utilizing the signal processing technique of coherent averaging. The technique is capable of high signal-to-noise measurements with personal computer data acquisition equipment, an amplifier/speaker, and a high quality microphone. When coupled with simple waveguide test systems fabricated from commercial PVC plumbing pipe, impulse response measurement has proven to be ideal for undergraduate research projects-often of publishable quality-or for advanced laboratory experiments. The technique provides important learning objectives for science or engineering students in areas such as interfacing and computer control of experiments; analog-to-digital conversion and sampling; time and frequency analysis using Fourier transforms; signal processing; and insight into a variety of current research areas such as acoustic bandgap materials, acoustic metamaterials, and fast and slow wave manipulation. PMID:22423798

Robertson, W M; Parker, J M

2012-03-01

403

Early Results on Radioactive Background Characterization for Sanford Laboratory and DUSEL Experiments  

E-print Network

Measuring external sources of background for a deep underground laboratory at the Homestake Mine is an important step for the planned low-background experiments. The naturally occurring $\\gamma$-ray fluxes at different levels in the Homestake Mine are studied using NaI detectors and Monte Carlo simulations. A simple algorithm is developed to convert the measured $\\gamma$-ray rates into $\\gamma$-ray fluxes. A good agreement between the measured and simulated $\\gamma$-ray fluxes is achieved with the knowledge of the chemical composition and radioactivity levels in the rock. The neutron fluxes and $\\gamma$-ray fluxes are predicted by Monte Carlo simulations for different levels including inaccessible levels that are under construction for the planned low background experiments.

D. -M. Mei; C. Zhang; K. Thomas; F. Gray

2009-12-01

404

Laboratory performance of the BEAR (Beam Experiment Aboard Rocket) RFQ (radio-frequency quadrupole)  

SciTech Connect

The BEAR (Beam Experiment Aboard Rocket) accelerator will be part of an experiment to demonstrate the operation of an ion accelerator in space and to characterize the exoatmospheric propagation of a neutral particle beam. The RFQ (radio-frequency quadrupole) has been designed to produce a 25-mA H/sup /minus// beam with an emittance of 0.01 cm-mrad (rms normalized) at an energy of 1 MeV. Because of the rigors of spaceflight, the accelerator design has been constrained by factors not normally applicable to conventional terrestrial accelerators. These factors and the mechanical features are described in a companion paper in these proceedings. The design techniques developed for BEAR would be applicable whenever, rugged, lightweight, or power-efficient systems are required. The BEAR RFQ has been operated under power with beam in the laboratory. This paper details of measured beam transport, emittance, and energy spectra. 6 refs., 4 figs.

O'Shea, P.G.; Schrage, D.L.; Young, L.M.; Zaugg, T.J.; Lynch, M.T.; McKenna, K.F.; Hansborough, L.D.

1988-01-01

405

Sediment trapping efficiency of adjustable check dam in laboratory and field experiment  

NASA Astrophysics Data System (ADS)

Check dam has been constructed at mountain area to block debris flow, but has been filled after several events and lose its function of trapping. For the reason, the main facilities of our research is the adjustable steel slit check dam, which with the advantages of fast building, easy to remove or adjust it function. When we can remove transverse beams to drain sediments off and keep the channel continuity. We constructed adjustable steel slit check dam on the Landow torrent, Huisun Experiment Forest station as the prototype to compare with model in laboratory. In laboratory experiments, the Froude number similarity was used to design the dam model. The main comparisons focused on types of sediment trapping and removing, sediment discharge, and trapping rate of slit check dam. In different types of removing transverse beam showed different kind of sediment removal and differences on rate of sediment removing, removing rate, and particle size distribution. The sediment discharge in check dam with beams is about 40%~80% of check dam without beams. Furthermore, the spacing of beams is considerable factor to the sediment discharge. In field experiment, this research uses time-lapse photography to record the adjustable steel slit check dam on the Landow torrent. The typhoon Soulik made rainfall amounts of 600 mm in eight hours and induced debris flow in Landow torrent. Image data of time-lapse photography demonstrated that after several sediment transport event the adjustable steel slit check dam was buried by debris flow. The result of lab and field experiments: (1)Adjustable check dam could trap boulders and stop woody debris flow and flush out fine sediment to supply the need of downstream river. (2)The efficiency of sediment trapping in adjustable check dam with transverse beams was significantly improved. (3)The check dam without transverse beams can remove the sediment and keep the ecosystem continuity.

Wang, Chiang; Chen, Su-Chin; Lu, Sheng-Jui

2014-05-01

406

Dedicated Laboratory Setup for CO2 TEA Laser Propulsion Experiments at Rensselaer Polytechnic Institute  

NASA Astrophysics Data System (ADS)

Laser propulsion research progress has traditionally been hindered by the scarcity of photon sources with desirable characteristics, as well as integrated specialized flow facilities in a dedicated laboratory environment. For TEA CO2 lasers, the minimal requirements are time-average powers of >100 W), and pulse energies of >10 J pulses with short duration (e.g., 0.1 to 1 ?s); furthermore, for the advanced pulsejet engines of interest here, the laser system must simulate pulse repetition frequencies of 1-10 kilohertz or more, at least for two (carefully sequenced) pulses. A well-equipped laser propulsion laboratory should have an arsenal of sensor and diagnostics tools (such as load cells, thrust stands, moment balances, pressure and heat transfer gages), Tesla-level electromagnet and permanent magnets, flow simulation facilities, and high-speed visualization systems, in addition to other related equipment, such as optics and gas supply systems. In this paper we introduce a cutting-edge Laser Propulsion Laboratory created at Rensselaer Polytechnic Institute, one of the very few in the world to be uniquely set up for beamed energy propulsion (BEP) experiments. The present BEP research program is described, along with the envisioned research strategy that will exploit current and expanded facilities in the near future.

Salvador, Israel I.; Kenoyer, David; Myrabo, Leik N.; Notaro, Samuel

2010-10-01

407

Virtual laboratory: assessment of a b-learning experience for teaching Physics in Engineering  

NASA Astrophysics Data System (ADS)

During the autumn semester of 2008/09 term, we have carried out an experience of teaching an innovative subject at our University. The subject is open and elective for all the students at the University, most of them in Engineering degrees. We call it "Physics virtual laboratory ". The students use a CMS (course management system) for accessing the syllabus, and the materials for the course. These materials include videos, sound and rich text for describing some well known experiments in a Physics lab. They also have a test for each unit and have to submit a written essay for every experiment at a fixed date. They work with the help of the teacher that answer their questions and provide solutions for the exercises, so this course is not entirely e-learning, but rather blended learning. For every unit, we have prepared materials that serve as a guide for the experiment, without being physically at the laboratory and without measuring any physical quantities. All the necessary data are given, and the real apparatus are shown in videos embedded in the document and described in detail. The experiments chosen cover those found in a typical Physics lab: kinematics in an air-cushion rail, Boyle-Mariotte law, magnetic field inside a solenoid, simple circuits, lenses… The number is limited to seven experiments for time constraint reasons. In a given experiment, we put emphasis in quantifying the uncertainty of the results, and several ways of calculating it are explained in detail using Excel spreadsheets. After the subject has ended, we have gathered feedback from the students, and have taken note of how they rate it compared with more traditional subjects. Also, we assess our work and the usefulness of the materials and the fitness of the structure of the subject. This is important for assuring that the change in methodology is better for the learing process. In this communication we present the results of this assessment and try to reach some conclusions that might be useful in many engineering subjects that use b-learning methodologies.

Ablanque, J.; Seidel, L.; Losada, J. C.

2009-04-01

408

Natural Sciences 2005/06 Cover: Glimpses of research conducted in the Attosecond Laser Laboratory (research leaders Dr John Tisch and Prof Jon  

E-print Network

: Glimpses of research conducted in the Attosecond Laser Laboratory (research leaders Dr John Tisch and Prof Jon Marangos). Work in this lab is focused on ultrafast laser physics and high-intensity laser-matter duration and to observe and manipulate the motion of electrons in matter on the attosecond time

409

Environmental Assessment for the proposed Induction Linac System Experiments in Building 51B at Lawrence Berkeley National Laboratory, Berkeley, California  

SciTech Connect

The US Department of Energy (DOE) has prepared an Environmental Assessment (EA), (DOE/EA-1087) evaluating the proposed action to modify existing Building 51B at Lawrence Berkeley National Laboratory (LBNL) to install and conduct experiments on a new Induction Linear Accelerator System. LBNL is located in Berkeley, California and operated by the University of California (UC). The project consists of placing a pre-fabricated building inside Building 51B to house a new 10 MeV heavy ion linear accelerator. A control room and other support areas would be provided within and directly adjacent to Building 51B. The accelerator system would be used to conduct tests, at reduced scale and cost, many features of a heavy-ion accelerator driver for the Department of Energy`s inertial fusion energy program. Based upon information and analyses in the EA, the DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969. Therefore, an Environmental Impact Statement is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI).

NONE

1995-08-01

410

Measurement of the Order Parameter in a Room Temperature Liquid Crystal: An Experiment for the Physical Chemistry Laboratory.  

ERIC Educational Resources Information Center

Presented here is a laboratory experiment for a course in physical chemistry. Students are requested to directly measure the degree of orientational order in a liquid crystal at room temperature. A minimum amount of equipment is necessary. (Author/SA)

DuPre, Donald B.; Chapoy, L. Lawrence

1979-01-01

411

Stability of quasi-Keplerian Shear Flow in a Laboratory Experiment  

SciTech Connect

Subcritical transition to turbulence has been proposed as a source of turbulent viscosity required for the associated angular momentum transport for fast accretion in Keplerian disks. Previously cited laboratory experiments in supporting this hypothesis were performed either in a di erent type of flow than Keplerian or without quantitative measurements of angular momentum transport and mean flow profile, and all of them appear to su er from Ekman e ects, secondary flows induced by nonoptimal axial boundary conditions. Such Ekman e ects are expected to be absent from astronomical disks, which probably have stress-free vertical boundaries unless strongly magnetized. Aims. To quantify angular momentum transport due to subcritical hydrodynamic turbulence, if exists, in a quasi-Keplerian flow with minimized Ekman e ects. Methods.We perform a local measurement of the azimuthal-radial component of the Reynolds stress tensor in a novel laboratory apparatus where Ekman e ects are minimized by flexible control of axial boundary conditions. Results.We find significant Ekman e ects on angular momentum transport due to nonoptimal axial boundary conditions in quasi-Keplerian flows. With the optimal control of Ekman e ects, no statistically meaningful angular momentum transport is detected in such flows at Reynolds number up to two millions. Conclusions. Either a subcritical transition does not occur, or, if a subcritical transition does occur, the associated radial transport of angular momentum in optimized quasi-Keplerian laboratory flows is too small to directly support the hypothesis that subcritical hydrodynamic turbulence is responsible for accretion in astrophysical disks. Possible limitations in applying laboratory results to astrophysical disks due to experimental geometry are discussed.

Ethan Schartman, Hantao Ji, Michael J. Burin and Jeremy Goodman

2012-06-19

412

The awareness of novelty for strangely familiar words: a laboratory analogue of the déjà vu experience.  

PubMed

Déjà vu is a nebulous memory experience defined by a clash between evaluations of familiarity and novelty for the same stimulus. We sought to generate it in the laboratory by pairing a DRM recognition task, which generates erroneous familiarity for critical words, with a monitoring task by which participants realise that some of these erroneously familiar words are in fact novel. We tested 30 participants in an experiment in which we varied both participant awareness of stimulus novelty and erroneous familiarity strength. We found that déjà vu reports were most frequent for high novelty critical words (?25%), with low novelty critical words yielding only baseline levels of déjà vu report frequency (?10%). There was no significant variation in déjà vu report frequency according to familiarity strength. Discursive accounts of the experimentally-generated déjà vu experience suggest that aspects of the naturalistic déjà vu experience were captured by this analogue, but that the analogue was also limited in its focus and prone to influence by demand characteristics. We discuss theoretical and methodological considerations relevant to further development of this procedure and propose that verifiable novelty is an important component of both naturalistic and experimental analogues of déjà vu. PMID:25401055

Urquhart, Josephine A; O'Connor, Akira R

2014-01-01

413

Rayleigh-Taylor instability at a tilted interface in laboratory experiments and numerical simulations  

NASA Astrophysics Data System (ADS)

This article investigates the molecular mixing caused by Rayleigh Taylor (RT) instability of a gravitationally unstable density interface tilted at a small angle to the horizontal. The mixing is measured by the increase in background potential energy, and the mixing efficiency, or fraction of energy irreversibly lost to fluid motion doing work against gravity, is calculated. Laboratory experiments are carried out using saline and fresh water, and modeled with compressible numerical simulations, with a suitable choice of parameters and initial conditions. The experiments show that the high cumulative efficiency of mixing in RT instability at a horizontal interface is only slightly reduced by an interface tilt of up to 10°, despite the strong overturning that occurs. Instantaneous mixing efficiencies as high as 0.5 0.6 are measured, when RT instability is active, with lower values of about 0.35 during the subsequent overturning. The numerical simulations capture the most unstable scales and the overturning motion well, but generate more mixing than the experiments, with the instantaneous mixing efficiency remaining at 0.5 for most of the run. The difference may be due to restratification at small scales in the high Prandtl number experiments.

Holford, Joanne M.; Dalziel, Stuart B.; Youngs, David

2003-07-01

414

Analyzing Inquiry Questions of High-School Students in a Gas Chromatography Open-Ended Laboratory Experiment  

ERIC Educational Resources Information Center

This paper describes the implementation of an open-ended inquiry experiment for high-school students, based on gas chromatography (GC). The research focuses on identifying the level of questions that students ask during the GC open inquiry laboratory, and it examines whether implementing the advanced inquiry laboratory opens up new directions for…

Blonder, Ron; Mamlock-Naaman, Rachel; Hofstein, Avi

2008-01-01

415

The Development and Testing of Environmental and Societal-Related College General Biology Laboratory Experiences. Final Report.  

ERIC Educational Resources Information Center

The purpose of this project was to develop and test the effectiveness of relevant and functional general biology laboratory experiences based on the various media with which the student came in day-to-day contact. The review of the literature pertaining to the development of innovative general biology laboratory procedures for the college level…

Lucido, Phillip J.

416

LabView Based Nuclear Physics Laboratory experiments as a remote teaching and training tool for Latin American Educational Centers  

SciTech Connect

A virtual laboratory via internet to provide a highly iterative and powerful teaching tool for scientific and technical discipline is given. The experimenter takes advantage of a virtual laboratory and he can execute nuclear experiment at introductory level e.g. Gamma ray detection with Geiger-Mueller Counter at remote location using internet communication technology.

Sajo-Bohus, L.; Greaves, E. D.; Barros, H.; Gonzalez, W. [Universidad Simon Bolivar, Apartado 89000, Caracas 1080A (Venezuela); Rangel, A. [Universidad del Zulia Maracaibo (Venezuela)

2007-10-26

417

Development of Hands-On Student Experience with Modern Facilities, Measurement Systems, and Uncertainty Analysis in Undergraduate Fluids Engineering Laboratories  

Microsoft Academic Search

Development described of hands-on student experience with modern facilities, measurement systems, and uncertainty analysis in undergraduate fluids engineering laboratories. Classroom and pre-lab lectures and laboratories teach students experimental fluid dynamics (EFD) methodology and uncertainty analysis (UA) procedures following a step-by-step approach, which mirrors the \\

Fred Stern; Marian Muste; Surageet Ghosh; Jun Shao; Don Yarbrough

418

Students' design of experiments: an inquiry module on the conduction of heat  

NASA Astrophysics Data System (ADS)

This article examines secondary students' design of experiments after engagement in an innovative and inquiry-oriented module on heat transfer. The module consists of an integration of hands-on experiments, simulated experiments and microscopic model simulations, includes a structured series of guided investigative tasks and was implemented for a sample of 24 lower secondary (compulsory education) school students in Greece. A post-instructional assessment comprising written tests and interviews of the sample of students was employed. The findings revealed that after implementation of the module, a respectable number of the students showed ability in experiment design skills such as forming hypotheses and successfully describing experimental procedure.

Hatzikraniotis, E.; Kallery, M.; Molohidis, A.; Psillos, D.

2010-07-01

419

Microbial impacts on the geochemistry evolution in a nuclear waste repository -Laboratory experiment of microbially mediated redox changes-  

NASA Astrophysics Data System (ADS)

It is important to investigate geochemical evolution around nuclear waste repositories, because geochemical conditions could affect radionuclide migration. Therefore, a laboratory jar experiment was conducted with subsurface sediments, in order to assess the response of the geochemical and microbial communities toward redox processes. The redox process was induced by exposure to air and discontinuation to sediment suspension, which simulated the process occurring during operation of nuclear waste repositories, i.e., tunnel excavation, transport of waste containers, and final backfilling. During the experiments, redox potential, dissolved oxygen, and pH in the suspension were measured, and the concentrations of dissolved ions concentration (e.g., NO3-, SO42- and organic acid), HCl-extractable iron, and also head space gasses (e.g., CO2, CH4) in the jar were analyzed. Moreover, microbial DNA was extracted from the suspension, and PCR-DGGE analysis was performed to analyze the response of microbial communities toward the geochemical changes. As a results, after discontinuation of air exposure with lactate amendment, redox potentials decreased from ca. +300 mV to -430 m V (vs. Ag/AgCl), and the sequential terminal electron-accepting process (TEAPs) was observed with the reactions of aerobic respiration, nitrate reduction, iron reduction, sulfate reduction, and methanogenesis. The related species of the microbes along with TEAPs, e.g., Pseudomonas sp. for nitrate reduction and Desulfovibrio sp. for sulfate reduction, was also detected. These results indicated that the microbial activities would affect the geochemical changes in nuclear repositories.

Nagaoka, T.

2010-12-01

420

Nobel Chemistry in the Laboratory: Synthesis of a Ruthenium Catalyst for Ring-Closing Olefin Metathesis--An Experiment for the Advanced Inorganic or Organic Laboratory  

ERIC Educational Resources Information Center

An experiment for the upper-level undergraduate laboratory is described in which students synthesize a ruthenium olefin metathesis catalyst, then use the catalyst to carry out the ring-closing metathesis of diethyl diallylmalonate. The olefin metathesis reaction was the subject of the 2005 Nobel Prize in chemistry. The catalyst chosen for this…

Greco, George E.

2007-01-01

421

Experiment on estimating thermal conductivity of sedimentary rocks from oil well logging  

SciTech Connect

Oil well logs are an important source of geothermal data for studying regional tectonics, reconstructing the evolution of sedimentary basins, and theorizing petroleum generation, migration, and accumulation. A more satisfactory, less laborious method of estimating the thermal conductivity of sedimentary rocks is badly needed. The thermal conductivity of cores from two gas wells in France was measured and correlated with neutron porosity index, sonic interval travel time, bulk density, and gamma-ray logs. To obtain reasonable predictions of conductivity, data were segregated into lithologic groups such as sand-shale, carbonate-shale, and carbonate-sand. A set of regression coefficients in the equation that predicts the conductivity from the logs was calculated for each group. The correlation coefficients between the measured and predicted conductivities of the core samples were 0.81, 0.75, and 0.61, respectively, for the three lithologic groups. The average percent difference between the measured and the calculated conductivities for the lithologies likely to be encountered in practice is 13.4%. The authors expect this figure can be reduced to 10% by enlarging the data base for calculating the regression coefficients. In the same basin or oil field, the relative errors from well to well probably will be 6% or smaller because the lithology will be nearly homogeneous. 4 figures, 5 tables.

Vacquier, V.; Mathieu, Y. Legendre, E.; Blondin, E.

1988-06-01

422

Experiments with 3 He quasiparticles in the collisionless regime. I. A direct measurement of the Fermi velocity by heat conduction  

Microsoft Academic Search

Measurements of the thermal conduction of liquid3He in the collisionless regime, where the mean free path of the thermal carriers is much greater than the channel diameter, allow a direct measurement of the carrier velocity. These experiments have been done using Vycor porous glass as the channel (average diameter ~70 Å) at temperatures down to 16 mK. They show that

D. S. Betts; D. F. Brewer; R. S. Hamilton

1974-01-01

423

Experiments with3He quasiparticles in the collisionless regime. I. A direct measurement of the Fermi velocity by heat conduction  

Microsoft Academic Search

Measurements of the thermal conduction of liquid 3 He in the collisionless regime, where the mean free path of the thermal carriers is much greater than the channel diameter, allow a direct measurement of the carrier velocity. These experiments have been done using Vycor porous glass as the channel (average diameter ˜70 Å) at temperatures down to 16 mK. They

D. S. Betts; D. F. Brewer; R. S. Hamilton

1974-01-01

424

ATR-FTIR Spectroscopy in the Undergraduate Chemistry Laboratory: Part II--A Physical Chemistry Laboratory Experiment on Surface Adsorption  

ERIC Educational Resources Information Center

Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy is a useful technique for measuring the infrared spectra of solids and liquids as well as probing adsorption on particle surfaces. The use of FTIR-ATR spectroscopy in organic and inorganic chemistry laboratory courses as well as in undergraduate research was presented…

Schuttlefield, Jennifer D.; Larsen, Sarah C.; Grassian, Vicki H.

2008-01-01

425

A Laboratory Experiment on Colliding Plasmas: A Glimpse into Astrophysical Processes  

NASA Astrophysics Data System (ADS)

Twenty years ago it was inconceivable that one could do laboratory experiments that had any bearing on astrophysical processes. The development of large, quiescent, highly magnetized plasma sources, coupled with the availability of high-energy lasers changed all that. Carefully planned experiments can have features similar to those in space although the scaling can never be exact. However measurements of quantities such as local magnetic fields can be done in the lab, not for events many parsecs away. Experiments can unveil phenomena that could be of paramount importance but are not part of the lexicon of current astrophysical models and can stimulate examination of concepts in a new light. Here we present an experiment in which two plasmas, initially far denser than a background magnetoplasma, collide as they move across a magnetic field. The dense plasmas are formed when laser beams strike two targets. The initial high beta plasmas expel the background magnetic fields and undergo instabilities as they move toward each other. The merging plasmas shed electrons aligned along the background magnetic field. This spawns the generation of intense electrostatic and electromagnetic waves. Initial bursts of fast particles evolve into complex, fully three-dimensional current systems. Magnetic field line reconnection events, magnetic flux forced together by the motion of the currents, occur at many locations throughout the plasma volume. The currents in the magnetoplasma are those of Alfvén waves and the physics of these waves plays a great role in the interaction. Magnetic fields and currents derived from them were measured at tens of thousands of spatial locations and as a function of time and are displayed in detailed images and movies. The moving dense plasma also churns up the background plasma and generates ion acoustic waves. The relation of this experiment to several phenomena in astrophysical plasmas will be discussed.

Gekelman, Walter; Vincena, S.; Collette, A.

2008-05-01

426

Quantitative imaging of contaminant distributions in heterogeneous porous media laboratory experiments  

NASA Astrophysics Data System (ADS)

Intermediate-scale laboratory experiments on heterogeneous porous media have been increasingly used for the study of saturated and unsaturated ground water systems. While the ability to reproduce field-scale heterogeneity in these experiments has advanced, the use of visualization or image analysis methods to characterize the spatial distribution of solute concentrations has largely remained at the homogeneous media level. To advance these imaging techniques we developed a generic image analysis package that, for the first time, automatically segments regions in photographic images that require unique concentration calibration curves due to varying porous media properties or lighting nonuniformities. As a robust test, our image analysis package was applied to an intermediate-scale flow tank experiment characterized by a correlated random permeability field with unprecedented resolution. Twenty-five distinct classes of porous media were developed and binned to the synthetic permeability field, creating an experimental field of 3456 rectangular cells and thereby ensuring the emplaced field closely matched the statistics of the original continuous distribution. Concentration distributions were determined for an experimental tracer run and the corresponding dispersion parameters were calculated. The closeness of the experimental, image-processed longitudinal dispersivity (4.6 × 10 - 2 m) to that obtained from the field statistics (9.1 × 10 - 2 m) verifies our image analysis technique.

McNeil, J. D.; Oldenborger, G. A.; Schincariol, R. A.

2006-03-01

427

Release and fate of fluorocarbons in a shredder residue landfill cell: 1. Laboratory experiments.  

PubMed

The shredder residues from automobiles, home appliances and other metal-containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to use laboratory experiments to estimate fluorocarbon release and attenuation processes in a monofill shredder residue (SR) landfill cell. Waste from the open SR landfill cell at the AV Miljø landfill in Denmark was sampled at three locations. The waste contained 1-3% metal and a relatively low fraction of rigid polyurethane (PUR) foam particles. The PUR waste contained less blowing agent (CFC-11) than predicted from a release model. However, CFC-11 was steadily released in an aerobic bench scale experiment. Anaerobic waste incubation bench tests showed that SRSR produced significant methane (CH(4)), but at rates that were in the low end of the range observed for municipal solid waste. Aerobic and anaerobic batch experiments showed that processes in SRSR potentially can attenuate the fluorocarbons released from the SRSR itself: CFC-11 is degraded under anaerobic conditions with the formation of degradation products, which are being degraded under CH(4) oxidation conditions prevailing in the upper layers of the SR. PMID:20435458

Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

2010-11-01

428

Laboratory measurements of dielectric permittivity and electrical conductivity as a function of water content of soils in the intermediate frequency domain (100 kHz - 10 MHz)  

NASA Astrophysics Data System (ADS)

This study focuses on the measurement of the electrical properties of soils in the intermediate frequency range (100 kHz - 10 MHz). The mapping of the soil moisture, necessitating the mapping the electrical properties in situ, requires preliminary laboratory measurements conducted under controlled conditions. The effective electrical conductivity ?(?) is usually measured in the low frequency range (< 100 kHz), and mainly related to the clay content of the soil. The effective dielectric permittivity ?(?) is generally obtained at high frequency (> 50 MHz), and related to the water content of the soil. In the intermediate frequency range both parameters depend on water and clay content. The determination of the water content thus requires estimating the effect of the clay content. To reach that goal, a series of laboratory measurements on artificial and natural samples have been undertaken. These laboratory measurements were carried out using a capacitive cell and an electrical square quadripole. The complex effective relative dielectric permittivity ?* is measured with the capacitive cell, and defined as follow: ?*=?'(?)+i[?'(?) - ?(?)/?.?0], where ? corresponds to the pulsation and ?0 is the dielectric constant of the vacuum. The objective is to study the contribution of water and clay content on the following parameters: ?'(?) the real relative dielectric permittivity, ?'(?) the dielectric losses, and ?(?) the real electrical conductivity. Moreover, using the electrical square quadripole enables to measure the 'direct-current' electrical conductivity ?DC. These two types of measurements allow to discriminate the factor linked with conduction phenomena (equal to ?'(?)/?.?0) in the imaginary part of ?*, strongly dependant of the clay fraction in the sample. Measures on sandy samples, coupled with theoretical modeling (effective medium theory) show that the H.F. relationship between ?'(?) and the water content can be extended until 1 MHz. In presence of clay, it is possible, using the measured ?DC, to separate the factor linked with conduction phenomena from the dielectric losses. Keywords: dielectric permittivity, electrical conductivity, water content, capacitive cell measurements

Kessouri, Pauline; Rejiba, Fayçal; Schamper, Cyril; Tabbagh, Alain

2010-05-01

429

Laboratory Modeling of Space experiments on Expulsion of CO2 ions. Application to Global Warming.  

NASA Astrophysics Data System (ADS)

An approach to expel minority species which can contribute to global warming from the upper atmosphere in the Arctic region by the use of HF electromagnetic waves has been proposed [1]. Laboratory plasma experiments have been designed to model various aspects of this concept - from the acquisiton of negative charges by green house gases such as CO2 to their ascent to the upper atmosphere and their acceleration and expulsion along the open magnetic field lines. Laboratory results are presented which confirmed the efficient gyro-resonance acceleration of minority ion species made possible through the space charge cancellation by majority species. The outflow of CO2 ions from the divergent magnetic field of a laboratory plasma device is measured at various background neutral pressures and for different amount of currents along the axial magnetic field. The central idea is to impart perpendicular energy to a selective ion species gyrating around the geomagnetic field at its cyclotron resonance. The wave field is produced by either modulating the auroral electrojet or from the nonlinear interaction between two electron plasma resonances. In the presence of the divergent polar geomagnetic field the accelerated perpendicular ion velocity is converted into an upward motion along open magnetic field lines. The ions thus removed will unlikely find their way back to the lower atmosphere. Negatively charged particles move upward by the fair-weather electric field and by atmospheric convection. When these ions reach above 120 km altitude where the ion gyro frequency is comparable to or greater than the ion- neutral collision frequency, they can be accelerated by EM fields through the gyro resonance interaction. The propagation of these low frequency waves to the upper atmosphere along the earth's magnetic field is permitted by the plasma dispersion relation. Laboratory experiments play an important role in confirming the theoretical prediction that ion cyclotron waves can grow in the presence of an axial electron current. This allows the utilization of free energy sources in the auroral ionosphere to expel the selected species. The feasibility of this concept depends on how efficiently the free energy can be directed towards this remediation. Experimental excitation of these low frequency waves using the HIPAS facility will be presented. By exciting ELF waves over a range of ion gyro frequencies of dominant ion species, dips were observed in the low frequency magnetometer at these frequencies suggesting that the ELF wave energy was absorbed by ion species at specific frequencies. Ion acceleration and expelling phenomenon over the polar regions have been observed by high latitude satellites as a natural process. A method of using the ground-based HIPAS LIDAR to directly observe this selective ion acceleration will be presented along with laboratory laser- induced- fluorescent experiments on doppler shifts. 1. Wong, A.Y. et al. AIP CIP 96-27719, Chap 3, pp 41-75, 1997

Wong, A. Y.

2007-05-01

430

Inventory Control: An Inexpensive and Easily Constructed Device for Quantitative Conductivity Experiments.  

ERIC Educational Resources Information Center

Presents a low cost system with easily replaced electrodes for use in general chemistry. Notes the accuracy and wide applicability permit easy use in physical or quantitative chemistry experiments. Provides schematic, theory, and helpful suggestions. (MVL)

Rettich, Timothy R.; Battino, Rubin

1989-01-01

431

Human Nutrition Research Conducted at State Agricultural Experiment Stations and 1890/Tuskegee Agricultural Research Programs.  

ERIC Educational Resources Information Center

Cooperative State Research Service-administered and state-appropriated State Agriculture Experiment Station funds for human nutrition research increased about two-fold from FY70-FY86, while the percentage of budget expended for this research decreased. (JOW)

Driskell, Judy A.; Myers, John R.

1989-01-01

432

MISSE PEACE Polymers: An International Space Station Environmental Exposure Experiment Being Conducted  

NASA Technical Reports Server (NTRS)

As part of the Materials International Space Station Experiment (MISSE), 41 different polymers are being exposed for approximately 1 1/2 years to the low-Earth-orbit (LEO) environment on the exterior of the International Space Station. MISSE is a materials flight experiment sponsored by the Air Force Research Lab/Materials Lab and NASA, and is the first external experiment on the space station. A similar set of 41 polymers will be flown as part of the Polymer Erosion and Contamination Experiment (PEACE) a shuttle flight experiment that is being developed at the NASA Glenn Research Center collaboratively with the Hathaway Brown School for girls. Therefore, these 41 polymers are collectively called the MISSE PEACE Polymers. The purpose of the MISSE PEACE Polymers experiment is to determine how durable polymers are in the LEO space environment where spacecraft, such as the space station, orbit. Polymers are commonly used as spacecraft materials because of their desirable properties such as good flexibility, low density, and certain electrical properties or optical properties (such as a low solar absorptance and high thermal emittance). Two examples of the use of polymers on the exterior of spacecraft exposed to the space environment include metalized Teflon FEP (fluorinated ethylene propylene, DuPont) thermal control materials on the Hubble Space Telescope, and polyimide Kapton (DuPont) solar array blankets.

deGroh, Kim K.; Banks, Bruce A.; Hammerstrom, Anne; Youngstrom, Erica; Kaminski, Carolyn; Marx, Laura; Fine, Elizabeth; Gummow, Jonathan D.; Wright, Douglas

2002-01-01

433

Psychology Experiments.  

ERIC Educational Resources Information Center

A goal of the PsychExperiments project was to reduce the financial burden on psychology departments for hardware/software used in their laboratories. In its third year, the PsychExperiments site now hosts 39 experiments. Over 200 classrooms worldwide have signed up as official site users and there have been nearly 10,000 data sessions conducted.…

McGraw, Ken; Tew, Mark D.; Williams, John E.

2001-01-01

434

Laboratory experiments on internal wave reflection and absorption at a simulated oceanic pycnocline  

NASA Astrophysics Data System (ADS)

Laboratory experiments have been performed to investigate the reflection of an internal wave beam with a "pycnocline" layer situated below an unstratified layer in order to simulate observed oceanic processes. An oscillating cylinder was used to generate wave beams in the well-known "St. Andrew's Cross" pattern that interacted with the pycnocline. The internal waves were observed and the incident and reflected amplitudes measured using the synthetic schlieren technique. In virtually all instances, near-perfect reflection or near-complete absorption at the pycnocline was observed, depending on the value of the pycnocline density gradient. The data indicate the existence of a transition from reflection to absorption that is a function of the ratio of the maximum BV frequency in the pycnocline to the BV frequency of the stratified layer.

Wunsch, Scott; Brandt, Alan

2010-11-01

435

Update on the ANAIS experiment. ANAIS-0 prototype results at the new Canfranc Underground Laboratory  

NASA Astrophysics Data System (ADS)

ANAIS experiment will look for dark matter annual modulation using NaI(Tl) scintillators at the Canfranc Underground Laboratory (LSC). Highly purified NaI(Tl) crystals are being developed to reach the required sensitivity. In a parallel way, the ANAIS-0 module (made with a low background St Gobain NaI(Tl) crystal) has been taking data at the LSC, testing different configurations: various photomultiplier tubes (PMTs) models with/without light guides. Low background PMTs with light guides and ultra low background PMTs without light guides have shown a similar contribution to the background. A complete simulation of the ANAIS-0 module with shielding in the different configurations tested has been carried out and compared with the experimental data, considering contributions to the background from NaI bulk contaminants, PMTs, light guides, quartz windows and shielding materials. A good understanding of the background above 500 keV can be reported.

Amaré, J.; Cebrián, S.; Cuesta, C.; Fortuño, D.; García, E.; Ginestra, C.; Gómez, H.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Ortiz de Solórzano, A.; Pobes, C.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.