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Sample records for laboratory collision experiments

  1. Investigating Attachment Behaviors of Cryptosporidium Parvum Oocysts Using Collision Efficiency in Laboratory Column Experiments

    NASA Astrophysics Data System (ADS)

    Park, Y.; Hou, L.; Atwill, R.; Packman, A. I.; Harter, T.

    2009-12-01

    Cryptosporidium is one of the most common enteric parasites of humans and domestic animals, and a number of outbreaks of Cryprosporidiosis, a diarrheal disease caused by Cryptosporidium have been reported worldwide. Natural porous media has been demonstrated to be an effective filter for removing Cryptosporidium parvum from contaminated water and the amount of Cryptosporidium filtered is known to be highly dependent on physical and chemical conditions of the porous media and the water. Cryptosporidium deposition in saturated porous media involves two main steps: approach and attachment. In contrast to the approach mechanisms, attachment processes have not been systematically described to predict a priori because theories that represent attachment behavior (colloid stability) such as DLVO are insufficient to explain experimental data. For this reason, attachment efficiency is calculated based on empirical data, typically experimental breakthrough curves in laboratory columns or field experiments. In this study, collision (attachment) efficiencies (α) of C. parvum oocyst were calculated to test the effect of chemical property changes on the association of oocysts with sand grains. The breakthrough curve data obtained from twelve column experiments and three models were employed to calculate single collector efficiency (η) and α. The first ten experiments were conducted by changing ionic strength and pH, and mixing with natural sediments under the same physical properties (same η). Our experiment results show that iron coating or clay/suspended solids mixture drastically enhanced oocyst deposition. The experiments also showed that increase in ionic strength and decrease in pH enhanced the attachment efficiency. However, the experiment with 100mM NaCl resulted in low attachment efficiency and the experiment with pH 8.5 showed similar attachment efficiency to the one at pH 7. Based on the results from two additional experiments with different flow velocities, it

  2. Verification of Compton Collision and Klein-Nishina Formulas--An Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Singhal, R. P.; Burns, A. J.

    1978-01-01

    Describes an experiment to verify the Compton collision formula and the angular dependance of the Klein-Nishina formula. Equipment used is a 1-mCi(137)Cs source, 2x2 in. NaI detector and a multichannel analyzer. Suitable for honor undergraduates. (Author/GA)

  3. Ball Collision Experiments

    ERIC Educational Resources Information Center

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  4. Degree of impactor fragmentation under collision with a regolith surface—Laboratory impact experiments of rock projectiles

    NASA Astrophysics Data System (ADS)

    Nagaoka, Hiroki; Takasawa, Susumu; Nakamura, Akiko M.; Sangen, Kazuyoshi

    2014-01-01

    Some meteorites consist of a mix of components of various parent bodies that were presumably brought together by past collisions. Impact experiments have been performed to investigate the degree of target fragmentation during such collisions. However, much less attention has been paid to the fate of the impactors. Here, we report the results of our study of the empirical relationship between the degree of projectile fragmentation and the impact conditions. Millimeter-sized pyrophyllite and basalt projectiles were impacted onto regolith-like sand targets and an aluminum target at velocities of up to 960 m s-1. Experiments using millimeter-sized pyrophyllite blocks as targets were also conducted to fill the gap between this study and the previous studies of centimeter-sized rock targets. The catastrophic disruption threshold for a projectile is defined as the energy density at which the mass of the largest fragment is the half of the original mass. The thresholds with the sand target were 4.5 ± 1.1 × 104 and 9.0 ± 1.9 × 104 J kg-1, for pyrophyllite and basalt projectiles, respectively. These values are two orders of magnitude larger than the threshold for impacts between pyrophyllite projectiles onto aluminum targets, but are qualitatively consistent with the fact that the compressive and tensile strengths of basalt are larger than those of pyrophyllite. The threshold for pyrophyllite projectiles and the aluminum target agrees with the threshold for aluminum projectiles and pyrophyllite targets within the margin of error. Consistent with a previous result, the threshold depended on the size of the rocks with a power of approximately -0.4 (Housen and Holsapple 1999). Destruction of rock projectiles occurred when the peak pressure was about ten times the tensile strength of the rocks.

  5. COLLIDE: Collisions into Dust Experiment

    NASA Technical Reports Server (NTRS)

    Colwell, Joshua E.

    1999-01-01

    The Collisions Into Dust Experiment (COLLIDE) was completed and flew on STS-90 in April and May of 1998. After the experiment was returned to Earth, the data and experiment were analyzed. Some anomalies occurred during the flight which prevented a complete set of data from being obtained. However, the experiment did meet its criteria for scientific success and returned surprising results on the outcomes of very low energy collisions into powder. The attached publication, "Low Velocity Microgravity Impact Experiments into Simulated Regolith," describes in detail the scientific background, engineering, and scientific results of COLLIDE. Our scientific conclusions, along with a summary of the anomalies which occurred during flight, are contained in that publication. We offer it as our final report on this grant.

  6. RELATIVISTIC HEAVY ION COLLISIONS: EXPERIMENT

    SciTech Connect

    Friedlander, Erwin M.; Heckman, Harry H.

    1982-04-01

    Relativistic heavy ion physics began as a 'no man's land' between particle and nuclear physics, with both sides frowning upon it as 'unclean', because on one hand, hadronic interactions and particle production cloud nuclear structure effects, while on the other, the baryonic environment complicates the interpretation of production experiments. They have attempted to review here the experimental evidence on RHI collisions from the point of view that it represents a new endeavor in the understanding of strong interaction physics. Such an approach appears increasingly justified; first, by the accumulation of data and observations of new features of hadronic interactions that could not have been detected outside a baryonic environment; second, by the maturation of the field owing to the advances made over the past several years in experimental inquiries on particle production by RHI, including pions, kaons, hyperons, and searches for antiprotons; and third, by the steady and progressive increase in the energy and mass ranges of light nuclear beams that have become available to the experiment; indeed the energy range has widened from the {approx} 0.2 to 2 AGeV at the Bevalac to {approx}4 AGeV at Dubna and recently, to the quantum jump in energies to {approx} 1000 equivalent AGeV at the CERN PS-ISR. Accompanying these expansions in the energy frontier are the immediate prospects for very heavy ion beams at the Bevalac up to, and including, 1 AGeV {sup 238}U, thereby extending the 'mass frontier' to its ultimate extent.

  7. An Organoleptic Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Risley, John M.

    1996-12-01

    Flavorings in foods and fragrances in personal care products is a topic often discussed in chemistry classes designed for the general education of non-science majors. A laboratory experiment has been designed to accompany the lecture topic. Compounds in ten different classes of organic molecules that are used in the fragrance and food industry are provided to students. Students whiff the vapors of each compound and describe the organoleptic properties using a set of terms utilized in the fragrance and food industry. A set of questions guides students to an understanding of the relationship between structure of molecules and smell. Students are permitted to create their own fragrance based on the results of the experiment. Student response has been favorable. The experiment rectifies misconceptions students have about structure and odor, and gives positive reinforcement to the lecture material.

  8. Two LANL laboratory astrophysics experiments

    SciTech Connect

    Intrator, Thomas P.

    2014-01-24

    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 overarching 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.

  9. Organic Laboratory Experiments.

    ERIC Educational Resources Information Center

    Smith, Sherrel

    1990-01-01

    Detailed is a method in which short pieces of teflon tubing may be used for collection tubes for collecting preparative fractions from gas chromatographs. Material preparation, laboratory procedures, and results of this method are discussed. (CW)

  10. Submillimeter Laboratory Investigations: Spectroscopy and Collisions

    NASA Technical Reports Server (NTRS)

    Herbst, Eric; DeLucia, Frank C.

    2002-01-01

    Currently, millimeter-wave and submillimeter-wave spectroscopy is conducted in our laboratory on several different types of spectrometers. Our standard spectrometer utilizes the output of a phase-locked klystron operating in the 40-60 GHz region, which is sent into a crossed-waveguide harmonic generator, or "multiplier". The high frequency millimeter-and submillimeter-wave radiation is transmitted via quasi-optical techniques through an absorption cell and then onto a detector, which is either an InSb hot electron bolometer cooled to 1.4 K or a Si bolometer cooled to 0.3 K. The detector response is sent to a computer for measurement and analysis. The frequency range produced and detected in this manner goes from 80 GHz to upwards of 1 THz. Spectra are normally taken with source modulation, with line frequencies typically measured to an accuracy of 50-100 kHz. Higher accuracy is available when needed. Recently, we developed a new, broad-band spectrometer in our laboratory based on a free-running backward wave oscillator (BWO) of Russian manufacture as the primary source of radiation. The so-called FASSST (fast-scan submillimeter spectroscopic technique) system uses fast-scan and optical calibration methods rather than the traditional locking techniques. The output power from the BWO is split such that 90% goes into the absorption cell while 10% is coupled to a 40-meter Fabry-Perot cavity, which yields fringe? for frequency measurement. Results from this spectrometer on the spectrum of nitric acid (HNO3) show that 100 GHz of spectral data can be obtained in 5 seconds with a measurement accuracy of 50 kHz. Currently, the frequency range of the FASSST system in our laboratory is roughly 100-700 GHz.

  11. Impact Crater Experiments for Introductory Physics and Astronomy Laboratories

    ERIC Educational Resources Information Center

    Claycomb, J. R.

    2009-01-01

    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,…

  12. Change of Collision Efficiency with Distance in Bacterial Transport Experiements

    SciTech Connect

    Dong, Hailiang; Scheibe, Timothy D.; Johnson, William P.; Monkman, Crystal; Fuller, Mark E.

    2006-05-01

    Previous bacterial transport studies have shown decreased bacterial adhesion with transport distance, largely based on laboratory core experiments. An inferred effect of microbial population variability is invoked to interpret experimental data, but there lacks direct measurement at field-scale, especially in correlation of transport distance with change of bacterial surface properties. This study was undertaken to determine change of collision efficiency with transport distance, taking advantage of the bacterial transport experiment in Oyster, VA in the summer of 2001. Upon injection of an adhesion deficient strain, Comamonas sp. DA001 into a up-gradient well, bacterial samples were taken from multi-level samplers along the flow path, and were injected into cores of 40 cm in length and 7.5 cm in diameter packed with homogenized sediment from the same site, South Oyster focus area (SOFA). Bacterial suspension samples were also measured for bacterial electrophoretic mobility distribution. Using filtration theory, collision efficiency, the probability of bacterial attachment to the grain surfaces upon collision and a quantitative measure of bacterial adhesion, was determined using CXTFIT model fitted attachment rate, measured grain size (10th percentile), porosity, flow velocity, and collector efficiency. Collision efficiency was also determined based on the fraction of retention in the cores. Contrary to previous results and interpretation of field-scale breakthrough curves, our experimentally determined collision efficiency increases with transport distance in the core experiments, which correlates with increasingly negative surface charge of the injected bacteria. Therefore we conclude that the apparent decrease in adhesion with transport distance in the field is strongly controlled by field-scale heterogeneity in physical and chemical aquifer properties and not by microbial population heterogeneity.

  13. High charge state, ion-atom collision experiments using accel-decel

    SciTech Connect

    Bernstein, E.M.; Clark, M.W.; Tanis, J.A.; Graham, W.G.

    1987-01-01

    Recent studies of /sub 16/S/sup 13 +/ + He collisions between 2.5 and 200 MeV, which were made using the accel-decel technique with the Brookhaven National Laboratory coupled MP tandem Van de Graaff accelerators, are discussed. Cross sections were measured for single electron-capture and -loss as well as K x rays correlated to electron-capture. Other planned ion-atom collision experiments requiring accel-decel are also presented. 18 refs., 3 figs.

  14. Customized Laboratory Experience in Physical Chemistry

    ERIC Educational Resources Information Center

    Castle, Karen J.; Rink, Stephanie M.

    2010-01-01

    A new physical chemistry laboratory experience has been designed for upper-level undergraduate chemistry majors. Students customize the first 10 weeks of their laboratory experience by choosing their own set of experiments (from a manual of choices) and setting their own laboratory schedule. There are several topics presented in the accompanying…

  15. Time-of-Flight Experiments in Molecular Motion and Electron-Atom Collision Kinematics

    ERIC Educational Resources Information Center

    Donnelly, Denis P.; And Others

    1971-01-01

    Describes a set of experiments for an undergraduate laboratory which demonstrates the relationship between velocity, mass, and temperature in a gas. The experimental method involves time-of-flight measurements on atoms excited to metastable states by electron impact. Effects resulting from recoil in the electron-atom collision can also be…

  16. Collision experiments between centimeter-sized protoplanetesimals in microgravity

    NASA Astrophysics Data System (ADS)

    Whizin, Akbar; Colwell, Joshua E.; Dove, Adrienne; Brisset, Julie; Cruz, Roberto; Foster, Zach

    2016-10-01

    In the early stages of planet formation in a protoplanetary disk the first coalescing bodies are weakly bound. Conditions in the disk, such as the presence of gas (drag), make further growth through centimeter and meter sized bodies difficult. For centimeter-sized aggregates self-gravity is almost non-existent and electrostatic surface forces such as van der Waals-type forces play a critical role in holding loosely bound rubble-piles together during their early formation. In order to understand how aggregates of this size grow we study the mechanical strengths, material, and collisional properties of cm-sized aggregates. The collisional outcomes between two aggregates can be determined by a set of definable collision parameters and experimental constraints on these parameters will aid in astrophysical models of planet formation. We have carried out a series of microgravity laboratory experiments in which we collide a pair of weakly bound aggregates together. In our free-fall chamber we collide two 3-cm aggregates together at collision velocities ranging from 50 to 220 cm/s and with pressure ~1 mbar. The aggregates are made of mm-sized silica bead particles and require internal cohesion to avoid fragmentation above modest collision speeds, which is supplied by adding H2O (later dehydrated) and between 0 - 0.1 g of a well-mixed liquid adhesive to simulate surface forces and bonds between particles. We measure the compressive strengths of the aggregates (0.5 - 10 kPa), find their coefficients of restitution (CoR), and determine their bouncing and fragmentation thresholds, over a range of velocities and internal strengths. We observed collisional outcomes such as bouncing, erosion (mass-loss), and fragmentation of the aggregates. We find the CoR of the aggregates to have a mean of 0.11 ± 0.1 with no dependence on velocity or strength. Impact velocities above ~2 m/s resulted in fragmentation of our aggregates, higher than the ~1 m/s threshold for porous dust aggregates

  17. Real-time collision avoidance in space: the GETEX experiment

    NASA Astrophysics Data System (ADS)

    Freund, Eckhard; Rossmann, Juergen; Schluse, Michael

    2000-10-01

    Intelligent autonomous robotic systems require efficient safety components to assure system reliability during the entire operation. Especially if commanded over long distances, the robotic system must be able to guarantee the planning of safe and collision free movements independently. Therefore the IRF developed a new collision avoidance methodology satisfying the needs of autonomous safety systems considering the dynamics of the robots to protect. To do this, the collision avoidance system cyclically calculates the actual collision danger of the robots with respect to all static and dynamic obstacles in the environment. If a robot gets in collision danger the methodology immediately starts an evasive action to avoid the collision and guides the robot around the obstacle to its target position. This evasive action is calculated in real-time in a mathematically exact way by solving a quadratic convex optimization problem. The secondary conditions of this optimization problem include the potential collision danger of the robots kinematic chain including all temporarily attached grippers and objects and the dynamic constraints of the robots. The result of the optimization procedure are joint accelerations to apply to prevent the robot from colliding and to guide it to its target position. This methodology has been tested very successfully during the Japanese/German space robot project GETEX in April 1999. During the mission, the collision avoidance system successfully protected the free flying Japanese robot ERA on board the satellite ETS-VII at all times. The experiments showed, that the developed system is fully capable of ensuring the safety of such autonomous robotic systems by actively preventing collisions and generating evasive actions in cases of collision danger.

  18. Fluid Flow Experiment for Undergraduate Laboratory.

    ERIC Educational Resources Information Center

    Vilimpochapornkul, Viroj; Obot, Nsima T.

    1986-01-01

    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)

  19. Multidimensional Screening as a Pharmacology Laboratory Experience.

    ERIC Educational Resources Information Center

    Malone, Marvin H.; And Others

    1979-01-01

    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…

  20. Simple Expalanation of a Well-Known Collision Experiment.

    ERIC Educational Resources Information Center

    Herrmann, F.; Schmalzle, P.

    1981-01-01

    Explains that the result of collision experiments with a linear arrangement of several identical elastic balls cannot be predicted solely from the conservation laws and energy and momentum. Indicates that the system of balls must be capable of dispersion-free energy propagation. (Author/JN)

  1. A Kinetic Experiment for the Biochemistry Laboratory.

    ERIC Educational Resources Information Center

    Palmer, Richard E.

    1986-01-01

    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)

  2. Laboratory Experience for Teaching Sensory Physiology

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

  3. Chemical Reaction Experiment for the Undergraduate Laboratory.

    ERIC Educational Resources Information Center

    Kwon, K. C.; And Others

    1987-01-01

    Provides an overview of an experiment on reaction kinetics of the anthracene-hydrogen system. Includes a description of the laboratory equipment, procedures, and data analysis requirements. Points out the advantages of the recommended technique. (ML)

  4. Laboratory experiments on columnar jointing

    NASA Astrophysics Data System (ADS)

    Goehring, L.; Morris, S. W.

    2003-12-01

    The mechanism causing columnar jointing has remained an enticing mystery since the basalt columns of the Giant's Causeway in N. Ireland were first reported to science in the 17th century. This phenomenon, in which shrinkage cracks form a quasi-hexagonal arrangement, has been shown to produce columns in starch, glass, coal, sandstone, and ice, as well as in a variety of lava flows. This suggests that this pattern-forming process is very general in nature. However, most studies of columnar jointing have been confined to field studies of basalt flows. Following Muller, we have experimented with desiccating corn starch in an effort to understand this pattern from a more general point of view. The diffusion and evaporation of water in starch is thought to be analogous to the diffusion and extraction of heat from a basalt flow. By combining direct sampling and x-ray tomography, fully 3D descriptions of columnar jointing were obtained with starch samples. We have characterized the pattern with several statistical indices, which describe its structure and relative disorder. These methods can resolve the ordering of the colonnade near the free surface. We identified two distinct mechanisms by which the mean column area increases during pattern evolution. We found both a slow, almost power-law increase in column area, as well as episodes of sudden catastrophic jumps in scale. The latter suggests that the column scale is not a simple single-valued function of drying rate, but rather a metastable state subject to hysteresis. Such metastable behaviour might explain a fundamental question about columnar jointing -- why the columns are so regular in the direction of their growth. Moreover, these experiments may help discriminate between the various theoretical models of this pattern forming process. Finally, our results lead to predictions that could be tested by field measurements on basaltic colonnades.

  5. Laboratory experience for teaching sensory physiology.

    PubMed

    Albarracín, Ana L; Farfán, Fernando D; Felice, Carmelo J

    2009-06-01

    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.

  6. Laboratory experiments on arc deflection and instability

    SciTech Connect

    Zweben, S.; Karasik, M.

    2000-03-21

    This article describes experiments on arc deflection instability carried out during the past few years at the Princeton University Plasma Physics Laboratory (PPPL). The approach has been that of plasma physicists interested in arcs, but they believe these results may be useful to engineers who are responsible for controlling arc behavior in large electric steel furnaces.

  7. Laser Mode Structure Experiments for Undergraduate Laboratories.

    ERIC Educational Resources Information Center

    Phillips, Richard A.; Gehrz, Robert D.

    Experiments dealing with laser mode structure are presented which are suitable for an upper division undergraduate laboratory. The theory of cavity modes is summarized. The mode structure of the radiation from a helium-neon laser is measured by using a photodiode detector and spectrum analyzer to detect intermode beating. Off-axial modes can be…

  8. Ultrafiltration of Protein Solutions: A Laboratory Experiment

    ERIC Educational Resources Information Center

    Pansare, Vikram J.; Tien, Daniel; Prud'homme, Robert K.

    2015-01-01

    Biology is playing an increasingly important role in the chemical engineering curriculum. We describe a set of experiments we have implemented in our Undergraduate Laboratory course giving students practical insights into membrane separation processes for protein processing. The goal of the lab is to optimize the purification and concentration of…

  9. Computer Based Simulation of Laboratory Experiments.

    ERIC Educational Resources Information Center

    Edward, Norrie S.

    1997-01-01

    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,…

  10. Experiments and scaling laws for catastrophic collisions. [of asteroids

    NASA Technical Reports Server (NTRS)

    Fujiwara, A.; Cerroni, P.; Davis, D.; Ryan, E.; Di Martino, M.

    1989-01-01

    The existing data on shattering impacts are reviewed using natural silicate, ice, and cement-mortar targets. A comprehensive data base containing the most important parameters describing these experiments was prepared. The collisional energy needed to shatter consolidated homogeneous targets and the ensuing fragment size distributions have been well studied experimentally. However, major gaps exist in the data on fragment velocity and rotational distributions, as well as collisional energy partitioning for these targets. Current scaling laws lead to predicted outcomes of asteroid collisions that are inconsistent with interpretations of astronomical data.

  11. Monitoring hydraulic fracture growth: Laboratory experiments

    SciTech Connect

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

    2000-04-01

    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.

  12. The BDX experiment at Jefferson Laboratory

    SciTech Connect

    Celentano, Andrea

    2015-06-01

    The existence of MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. The Beam Dump eXperiment (BDX) at Jefferson Laboratory aims to investigate this mass range. Dark matter particles will be detected through scattering on a segmented, plastic scintillator detector placed downstream of the beam-dump at one of the high intensity JLab experimental Halls. The experiment will collect up to 1022 electrons-on-target (EOT) in a one-year period. For these conditions, BDX is sensitive to the DM-nucleon elastic scattering at the level of a thousand counts per year, and is only limited by cosmogenic backgrounds. The experiment is also sensitive to DM-electron elastic and inelastic scattering, at the level of 10 counts/year. The foreseen signal for these channels is a high-energy (> 100 MeV) electromagnetic shower, with almost no background. The experiment has been presented in form of a Letter of Intent to the laboratory, receiving positive feedback, and is currently being designed.

  13. Controlled Space Physics Experiments using Laboratory Magnetospheres

    NASA Astrophysics Data System (ADS)

    Mauel, M. E.; Kesner, J.; Garnier, D.

    2013-12-01

    Modern society's reliance on space-based platforms for a variety of economic and geopolitical purposes makes understanding the physics of the magnetosphere and "space weather'' one of the most important applications of plasma science. During the past decade, results from the CTX and LDX laboratory magnetospheres and from the RT-1 device at University of Tokyo, we have developed techniques to explore space physics using controlled experiments in laboratory magnetospheres. This presentation briefly reviews observations from the laboratory magnetospheres at Columbia University and MIT, including adiabatic drift-resonant transport, low-frequency MHD turbulence, and the formation of high-beta plasmas with profiles similar to Earth's inner magnetosphere. First principle validation of ``whole plasma'' space weather models have been completed in relevant magnetic geometry, including the spectrum and dynamics of turbulence successfully modeled with nonlinear bounce-averaged gyrokinetic simulations. Plans to explore Alfvénic dynamics and whistler wave trapping are discussed through the achievement of higher-density plasmas using radio-frequency heating. Photographs of the laboratory magnetospheres located at MIT (top) and Columbia University (bottom).

  14. Experience of maintaining laboratory educational website's sustainability

    PubMed Central

    Dimenstein, Izak B.

    2016-01-01

    Laboratory methodology websites are specialized niche websites. The visibility of a niche website transforms it into an authority site on a particular “niche of knowledge.” This article presents some ways in which a laboratory methodology website can maintain its sustainability. The optimal composition of the website includes a basic content, a blog, and an ancillary part. This article discusses experimenting with the search engine optimization query results page. Strategic placement of keywords and even phrases, as well as fragmentation of the post's material, can improve the website's visibility to search engines. Hyperlinks open a chain reaction of additional links and draw attention to the previous posts. Publications in printed periodicals are a substantial part of a niche website presence on the Internet. Although this article explores a laboratory website on the basis of our hands-on expertise maintaining “Grossing Technology in Surgical Pathology” (www.grossing-technology.com) website with a high volume of traffic for more than a decade, the recommendations presented here for developing an authority website can be applied to other professional specialized websites. The authority websites visibility and sustainability are preconditions for aggregating them in a specialized educational laboratory portal. PMID:27688928

  15. The laboratory investigation of surface envelope solitons: reflection from a vertical wall and collisions of solitons

    NASA Astrophysics Data System (ADS)

    Slunyaev, Alexey; Klein, Marco; Clauss, Günther F.

    2016-04-01

    Envelope soliton solutions are key elements governing the nonlinear wave dynamics within a simplified theory for unidirectional weakly modulated weakly nonlinear wave groups on the water surface. Within integrable models the solitons preserve their structure in collisions with other waves; they do not disperse and can carry energy infinitively long. Steep and short soliton-like wave groups have been shown to exist in laboratory tests [1] and, even earlier, in numerical simulations [2, 3]. Thus, long-living wave groups may play important role in the dynamics of intense sea waves and wave-structure interactions. The solitary wave groups may change the wave statistics and can be taken into account when developing approaches for the deterministic forecasting of dangerous waves, including so-called rogue waves. An experimental campaign has been conducted in the wave basin of the Technical University of Berlin on simulations of intense solitary wave groups. The first successful experimental observation of intense envelope solitons took place in this facility [1]. The new experiments aimed at following main goals: 1) to reproduce intense envelope solitons with different carrier wave lengths; 2) to estimate the rate of envelope soliton dissipation; 3) to consider the reflection of envelope solitons on a vertical wall; 4) to consider head-on collisions of envelope solitons, and 5) to consider overtaking interactions of envelope solitons. Up to 9 wave gauges were used in each experimental run, which enabled registration of the surface movement at different distances from the wavemaker, at different locations across the wave flume and near the wall. Besides surface displacements, the group envelope shapes were directly recorded, with use of phase shifts applied to the modulated waves generated by the wavemaker. [1] A. Slunyaev, G.F. Clauss, M. Klein, M. Onorato, Simulations and experiments of short intense envelope solitons of surface water waves. Phys. Fluids 25, 067105

  16. Laboratory experiments from the toy store

    NASA Technical Reports Server (NTRS)

    Mcclelland, H. T.

    1992-01-01

    The following is a laboratory experiment designed to further understanding of materials science. This material could be taught to a typical student of materials science or manufacturing at the high school level or above. The objectives of this experiment are as follows: (1) to qualitatively demonstrate the concepts of elasticity, plasticity, and the strain rate and temperature dependence of the mechanical properties of engineering materials; (2) to qualitatively demonstrate the basics of extrusion including material flow, strain rate dependence of defects, lubrication effects, and the making of hollow shapes by extrusion (the two parts may be two separate experiments done at different times when the respective subjects are covered); and (3) to demonstrate the importance of qualitative observations and the amount of information which can be gathered without quantitative measurements.

  17. Optimizing Laboratory Experiments for Dynamic Astrophysical Phenomena

    SciTech Connect

    Ryutov, D; Remington, B

    2005-09-13

    To make a laboratory experiment an efficient tool for the studying the dynamical astrophysical phenomena, it is desirable to perform them in such a way as to observe the scaling invariance with respect to the astrophysical system under study. Several examples are presented of such scalings in the area of magnetohydrodynamic phenomena, where a number of scaled experiments have been performed. A difficult issue of the effect of fine-scale dissipative structures on the global scale dissipation-free flow is discussed. The second part of the paper is concerned with much less developed area of the scalings relevant to the interaction of an ultra-intense laser pulse with a pre-formed plasma. The use of the symmetry arguments in such experiments is also considered.

  18. Controlled Space Physics Experiments using Laboratory Magnetospheres

    NASA Astrophysics Data System (ADS)

    Mauel, Michael; Davis, M.; Garnier, D.; Roberts, T. M.; Worstell, M.; Kesner, J.

    2013-10-01

    Modern society's reliance on space-based platforms for a variety of economic and geopolitical purposes makes understanding the physics of the magnetosphere and ``space weather'' one of the most important applications of plasma science. During the past decade, results from the CTX and LDX laboratory magnetospheres and from the RT-1 device at University of Tokyo, we have developed techniques to explore space physics using controlled experiments in laboratory magnetospheres. This presentation briefly reviews observations from the laboratory magnetospheres at Columbia University and MIT, including adiabatic drift-resonant transport, low-frequency MHD turbulence, and the formation of high-beta plasmas with profiles similar to Earth's inner magnetosphere. First principle validation of ``whole plasma'' space weather models have been completed in relevant magnetic geometry, including the spectrum and dynamics of turbulence successfully modeled with nonlinear bounce-averaged gyrokinetic simulations. Plans to explore Alfvénic dynamics and whistler wave trapping are discussed through the achievement of higher-density plasmas using radio-frequency heating. Supported by the NSF-DOE Partnership in Plasma Science.

  19. Threshold collision induced dissociation experiment for azobenzene and its derivatives

    NASA Astrophysics Data System (ADS)

    Rezaee, Mohammadreza; Compton, Robert

    In this study we investigated protonated azobenzene cation and properties of trans 2,2',6,6'-tetrafluoroazobenzene anion using the collision induced dissociation method and the results are compared with the results from ab initio electronic structure calculations. We measured the bond dissociation energies experimentally and found which theoretical quantum chemistry methods yield best results. Several high accuracy multi-level calculations such as CBS-QB3, G3 and G4 had been carried out to obtain reliable thermochemical information for azobenzene and several of its derivatives and their anion or cation. We also performed other experiments such as Raman spectroscopy to study these light sensitive molecules with promising applications such as photo-switching.

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

    ERIC Educational Resources Information Center

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

    2003-01-01

    Dicusses the effects of using laboratory assistants for disabled students' learning in the chemistry laboratory. Presents two case studies and general strategies for approaching laboratory experiences for disabled students. (KHR)

  1. Laboratory Experiments of Rip Current Generation

    NASA Astrophysics Data System (ADS)

    Garnier, R.; Coco, G.; Lomonaco, P.; Dalrymple, R. A.; Alvarez, A.; Gonzalez, M.; Medina, R.

    2014-12-01

    The hypothesis of rip current generation from purely hydrodynamic processes is here investigated through laboratory experiments. The experiments have been performed at the Cantabria Coastal and Ocean Basin (CCOB) with a segmented wavemaker consisting of 64 waveboards. The basin measures 25m in the cross-shore and 32m in the alongshore direction and the water depth at the wavemaker is 1m. A concrete plane sloping (1:5) beach has been built in the opposite side of the wave machine, its toe is 15m from the waveboards. Reflective lateral walls covered the full length of the basin. The set of instruments consists of 33 wave gauges deployed along two longshore and two cross-shore transects, 7 acoustic Doppler velocimeters and 15 run-up wires. Furthermore a set of two cameras has been synchronized with the data acquisition system. Two types of experiments have been performed to specifically study the generation of rip currents under wave group forcing. First, similarly to the experiments of Fowler and Dalrymple (Proc. 22nd Int. Conf. Coast. Eng.,1990), two intersecting wave trains with opposite directions have been imposed. They give rise to the formation of a non-migrating rip current system with a wavelength that depends on wave frequency and direction. Second, single wave trains with alongshore periodic amplitude attenuation have been imposed. Although the attenuation has been set such that the incident wave field has the same envelope as in the first type of experiments, the rip current system differs due to diffraction and interference processes. The results for different wave conditions (maximum incident wave height from 0.2m to 0.4m, wave period from 1.4s to 2s) will be presented and the intensity of the rip currents will be compared to the alongshore variation in wave set-up. This research is part of the ANIMO project funded by the Spanish Government under contract BIA2012-36822.

  2. Experiment definition phase shuttle laboratory LDRL-10.6 experiment

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This report for the Experiment Definition Phase of the Shuttle Laboratory LDRL 10.6 Micrometer Experiment covers period 27 June through 26 September 1975. Activities during the fifth quarter included: (1) reevaluation of system obscuration ratio with a subsequent reduction of this ratio from 0.417 to 0.362, (2) completion of detail drawings for the 6X pre-expander, (3) completion of detail drawings for the nine mirrors that comprise pointing and tracking optomechanical subsystem, (4) continuation of detailing of mechanical portions of CMSS and modifications to accommodate new obscuration ratio, (5) qualitative operation of the optomechanical subsystem of the 10.6 um receiver achieved under experiment measurement task; receiver fully integrated and operation demonstrated over a 10 km experimental link, and (6) data collection task initiated to begin preparation of link analysis volumes.

  3. Turbulent flows and intermittency in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Anselmet, F.; Antonia, R. A.; Danaila, L.

    2001-10-01

    In turbulent flows, the transfer of energy from large to small scales is strongly intermittent, in contradiction with Kolmogorov's (Dokl. Akad. Nauk. SSSR 30 (1941) 299; hereafter K41) assumptions. The statistical properties associated with these energy transfer fluctuations at a given scale r have been widely studied theoretically, experimentally and numerically over the last 30 years or so. Such fluctuations are also encountered in various Planetary and Space Science domains. The present paper presents a review of laboratory experiments which clearly display the fractal nature of the (spatial or temporal) energy distribution at scale r, the departures from the K41 predictions being generally quantified through high-order moments of velocity increments.

  4. Impact fracture experiments simulating interstellar grain-grain collisions

    NASA Technical Reports Server (NTRS)

    Freund, Friedemann; Chang, Sherwood; Dickinson, J. Thomas

    1990-01-01

    Oxide and silicate grains condensing during the early phases of the formation of the solar system or in the outflow of stars are exposed to high partial pressures of the low-z elements H, C, N and O and their simple gaseous compounds. Though refractory minerals are nominally anhydrous and non-carbonate, if they crystallize in the presence of H2O, N2 and CO or CO2 gases, they dissolve traces of the gaseous components. The question arises: How does the presence of dissolved gases or gas components manifest itself when grain-grain collisions occur. What are the gases emitted when grains are shattered during a collision event. Researchers report on fracture experiments in ultrahigh vacuum (UHV, approximately less than 10 to the -8th power mbar) designed to measure (by means of a quadrupole mass spectrometer, QMS, with microns to ms time resolution) the emission of gases and vapors during and after impact (up to 1.5 sec). Two terrestrial materials were chosen which represent structural and compositional extremes: olivine (San Carlos, AZ), a densely packed Mg-Fe(2+) silicate from the upper mantle, available as 6 to 12 mm single crystals, and obsidian (Oregon), a structurally open, alkaline-SiO2-rich volcanic glass. In the olivine crystals OH- groups have been identified spectroscopically, as well as H2 molecules. Obsidian is a water-rich glass containing OH- besides H2O molecules. Olivine from the mantle often contains CO2, either as CO2-rich fluid in fluid inclusions or structurally dissolved or both. By analogy to synthetic glasses CO2 in the obsidian may be present in form of CO2 molecules in voids of molecular dimensions, or as carbonate anions, CO3(2-). No organic molecules have been detected spectroscopically in either material. Results indicate that refractory oxide/silicates which contain dissolved traces of the H2O and CO/CO2 components but no spectroscopically detectable traces of organics may release complex H-C-O (possibly H-C-N-O) molecules upon fracture

  5. Laboratory experiments of salt water intrusion

    NASA Astrophysics Data System (ADS)

    Crestani, Elena; Camporese, Matteo; Salandin, Paolo

    2015-04-01

    The problem of saltwater intrusion in coastal aquifers is dealt with by the proper setup of a sand-box device to develop laboratory experiments in a controlled environment. Saline intrusion is a problem of fundamental importance and affects the quality of both surface water and groundwater in coastal areas. In both cases the phenomenon may be linked to anthropogenic (construction of reservoirs, withdrawals, etc.) and/or natural (sea-level excursions, variability of river flows, etc.) changes. In recent years, the escalation of this problem has led to the development of specific projects and studies to identify possible countermeasures, typically consisting of underground barriers. Physical models are fundamental to study the saltwater intrusion problem, since they provide benchmarks for numerical model calibrations and for the evaluation of the effectiveness of solutions to contain the salt wedge. In order to study and describe the evolution of the salt wedge, the effectiveness of underground barriers, and the distance from the coast of a withdrawal that guarantees a continuous supply of fresh water, a physical model has been realized at the University of Padova to represent the terminal part of a coastal aquifer. It consists of a laboratory flume 500 cm long, 30 cm wide and 60 cm high, filled for an height of 45 cm with glass beads with a d50 of 0.6 mm and a uniformity coefficient d60/d10~= 1.5. The material is homogeneous and characterized by a porosity of about 0.37 and by an hydraulic conductivity of about 1.8×10-3 m/s. Upstream from the sand-box, a tank, continuously supplied by a pump, provides fresh water to recharge the aquifer, while the downstream tank, filled with salt water, simulates the sea. The volume of the downstream tank (~= 2 m3) is about five times the upstream one, so that density variations due to the incoming fresh water flow are negligible. The water level in the two tanks is continuously monitored by means of two level probes and is

  6. Newton's cradle undone: Experiments and collision models for the normal collision of three solid spheres

    NASA Astrophysics Data System (ADS)

    Donahue, C. M.; Hrenya, C. M.; Zelinskaya, A. P.; Nakagawa, K. J.

    2008-11-01

    Using an apparatus inspired by Newton's cradle, the simultaneous, normal collision between three solid spheres is examined. Namely, an initially touching, motionless pair of "target" particles (doublet) is impacted on one end by a third "striker" particle. Measurements of postcollisional velocities and collision durations are obtained via high-speed photography and an electrical circuit, respectively. Contrary to intuition, the expected Newton's cradle outcome of a motionless, touching particle pair at the bottom of the pendulum arc is not observed in either case. Instead, the striker particle reverses its direction and separates from the middle particle after collision. This reversal is not observed, however, if the target particles are separated by a small distance (not in contact) initially, although a separation still occurs between the striker and middle particle after the collision, with both particles traveling in the same direction. For the case of initially touching target particles, contact duration measurements indicate that the striker separates from the three particles before the two target particles separate. However, when the targets are slightly separated, a three-particle collision is never observed, and the collision is, in fact, a series of two-body collisions. A subsequent implementation of a variety of hard-sphere and soft-sphere collision models indicates that a three-body (soft-sphere) treatment is essential for predicting the velocity reversal, consistent with the experimental findings. Finally, a direct comparison between model predictions and measurements of postcollisional velocities and contact durations provides a gauge of the relative merits of existing collision models for three-body interactions.

  7. Experiment definition phase shuttle laboratory. LDRL-10.6 experiment

    NASA Technical Reports Server (NTRS)

    1976-01-01

    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.

  8. Plume Electrification: Laboratory and Numerical Experiments

    NASA Astrophysics Data System (ADS)

    Mendez, J. S.; Dufek, J.

    2012-12-01

    The spectacular lightning strokes observed during eruptions testify to the enormous potentials that can be generated within plumes. Related to the charging of individual ash particles, large electric fields and volcanic lightning have been observed at Eyjafjallajokull, Redoubt, and Chaiten, among other volcanoes. A number of mechanisms have been proposed for plume electrification, including triboelectric charging, charging from the brittle failure of rock, and charging due to phase change as material is carried aloft. While the overall electrification of the plume likely results from a combination of these processes, in the following work we focus on triboelectric charging—how a plume charges as particles collide with each other. To explore the role of triboelectric effects in plume charging we have conducted a number of small scale laboratory experiments similar to those designed by Forward et al (2009). Succinctly, the experiments consist of fluidizing an ash bed with nitrogen and monitoring the resulting currents induced by the moving particles. It is important to note that the reaction chamber only allows particle-particle interactions. The entire experimental setup is enclosed in a vacuum chamber, allowing us to carefully control the environment during experiments. Runs were carried out for different ash compositions, and driving pressures. We particularly focused on natural grain size distributions of ash and on quantifying not only the net charge but also the charging rate. Furthermore, we report on our progress to incorporate the collected data, namely charging rates, into a large eularian-eularian-lagrangian multiphase eruption dynamic model. Finally, to validate these results, we present our plans to deploy a large wireless sensor network of electrometers and magnetometers around active volcanoes to directly map the overhead E- and M-fields as an eruption occurs.

  9. Magnetized laboratory plasma jets: experiment and simulation.

    PubMed

    Schrafel, Peter; Bell, Kate; Greenly, John; Seyler, Charles; Kusse, Bruce

    2015-01-01

    Experiments involving radial foils on a 1 MA, 100 ns current driver can be used to study the ablation of thin foils and liners, produce extreme conditions relevant to laboratory astrophysics, and aid in computational code validation. This research focuses on the initial ablation phase of a 20 μm Al foil (8111 alloy), in a radial configuration, driven by Cornell University's COBRA pulsed power generator. In these experiments ablated surface plasma (ASP) on the top side of the foil and a strongly collimated axial plasma jet are observed developing midway through the current rise. With experimental and computational results this work gives a detailed description of the role of the ASP in the formation of the plasma jet with and without an applied axial magnetic field. This ∼1 T field is applied by a Helmholtz-coil pair driven by a slow, 150 μs current pulse and penetrates the load hardware before arrival of the COBRA pulse. Several effects of the applied magnetic field are observed: (1) without the field extreme-ultraviolet emission from the ASP shows considerable azimuthal asymmetry while with the field the ASP develops azimuthal motion that reduces this asymmetry, (2) this azimuthal motion slows the development of the jet when the field is applied, and (3) with the magnetic field the jet becomes less collimated and has a density minimum (hollowing) on the axis. PERSEUS, an XMHD code, has qualitatively and quantitatively reproduced all these experimental observations. The differences between this XMHD and an MHD code without a Hall current and inertial effects are discussed. In addition the PERSEUS results describe effects we were not able to resolve experimentally and suggest a line of future experiments with better diagnostics.

  10. Organic Laboratory Experiments: Micro vs. Conventional.

    ERIC Educational Resources Information Center

    Chloupek-McGough, Marge

    1989-01-01

    Presents relevant statistics accumulated in a fall organic laboratory course. Discusses laboratory equipment setup to lower the amount of waste. Notes decreased solid wastes were produced compared to the previous semester. (MVL)

  11. Simulating Astrophysical Jets in Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Bellan, Paul

    2004-11-01

    A laboratory plasma configuration based on spheromak [1] magnetic fusion plasma physics technology is used to simulate many important features of magnetically driven astrophysical jets. The experimental sequence starts with a quasi-static seed poloidal magnetic field that links a central disk electrode to a co-planar bounding annular electrode; this arrangement provides a topology analogous to the poloidal magnetic field of a star linking a surrounding accretion disk. After puffing neutral gas from nozzles mounted on the electrodes, plasma is created via application of a large emf between the central disk and the bounding annular electrode. The emf then drives a large poloidal electric current flowing from the central disk electrode (star) to the annulus (accretion disk) along the bias poloidal magnetic field. This electric current produces large magnetohydrodynamic forces which result in dynamics analogous to the dynamics of an astrophysical jet. In particular, the laboratory "astrophysical jet" is observed [2,3] to evolve through a distinct, reproducible sequence consisting of jet formation, collimation, kink instability, and for appropriate parameters, detachment into an unbounded, expanding spheromak-like plasmoid. These observations and related observations on a solar prominence simulation experiment [4] have motivated an analytic model [5] for the collimation physics whereby stagnation of convected, frozen-in toroidal magnetic flux amplifies the toroidal magnetic flux density and then, since the toroidal magnetic field (i.e., toroidal flux density) provides the pinch force, the pinch force is increased, collimating the jet. The following talk (You, Bellan, Yun) will present detailed measurements of the jet formation, acceleration, and collimation process. [1] P. M. Bellan, Spheromaks (Imperial College Press, London, 2000). [2] S. C. Hsu and P. M. Bellan, Mon. Not. R. Astron. Soc. 334, 257 (2002). [3] S. C. Hsu and P. M. Bellan, Phys. Rev. Letters 90, article

  12. Validating the Collision-Dominated Child-Langmuir Law for a DC Discharge Cathode Sheath in an Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Lisovskiy, V.; Yegorenkov, V.

    2009-01-01

    In this paper, we propose a simple method of observing the collision-dominated Child-Langmuir law in the course of an undergraduate laboratory work devoted to studying the properties of gas discharges. To this end we employ the dc gas discharge whose properties are studied in sufficient detail. The undergraduate laboratory work itself is reduced…

  13. Electron beam injection experiments - Replication of flight observations in a laboratory beam plasma discharge

    NASA Technical Reports Server (NTRS)

    Bernstein, W.; Mcgarity, J. O.; Konradi, A.

    1983-01-01

    Recent electron beam injection experiments in the lower ionosphere have produced two perplexing results: (1) At altitudes from 140 km to 220 km, the beam associated 391.4 nm intensity is relatively independent of altitude despite the decreasing N2 abundance. (2) The radial extent of the perturbed region populated by beam associated energetic electrons significantly exceeds the nominal gyrodiameter for 90 deg injection. A series of laboratory measurements is described in which both of these flight results appear to have been closely reproduced. The laboratory results are reasonably consistent with the transition from a collision dominated to collisionless beam-plasma discharge configuration.

  14. Sensor-Based Collision Avoidance: Theory and Experiments

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun; Steele, Robert; Ivlev, Robert

    1996-01-01

    A new on-line control strategy for sensor-based collision avoidance of manipulators and supporting experimental results are presented in this article. This control strategy is based on nullification of virtual forces applied to the end-effector by a hypothetical spring-plus-damper attached to the object's surface. In the proposed approach, the real-time arm control software continuously monitors the object distance measured by the arm-mounted proximity sensors. When this distance is less than a preset threshold, the collision avoidance control action is initiated to inhibit motion toward the object and thus prevent collision. This is accomplished by employing an outer feedback loop to perturb the end-effector nominal motion trajectory in real-time based on the sensory data. The perturbation is generated by a proportional-plus-integral (PI) collision avoidance controller acting on the difference between the sensed distance and the preset threshold. This approach is computationally very fast, requires minimal modification to the existing manipulator positioning system, and provides the manipulator with an on-line collision avoidance capability to react autonomously and intelligently. A dexterous RRC robotic arm is instrumented with infrared proximity sensors and is operated under the proposed collision avoidance strategy. Experimental results are presented to demonstrate end-effector collision avoidance both with an approaching object and while reaching inside a constricted opening.

  15. A novel molecular synchrotron for cold collision and EDM experiments

    PubMed Central

    Hou, Shunyong; Wei, Bin; Deng, Lianzhong; Yin, Jianping

    2016-01-01

    Limited by the construction demands, the state-of-the-art molecular synchrotrons consist of only 40 segments that hardly make a good circle. Imperfections in the circular structure will lead to the appearance of unstable velocity regions (i.e. stopbands), where molecules of certain forward velocity will be lost from the structure. In this paper, we propose a stopband-free molecular synchrotron. It contains 1570 ring electrodes, which nearly make a perfect circle, capable of confining both light and heavy polar molecules in the low-field-seeking states. Molecular packets can be conveniently manipulated with this synchrotron by various means, like acceleration, deceleration or even trapping. Trajectory calculations are carried out using a pulsed 88SrF molecular beam with a forward velocity of 50 m/s. The results show that the molecular beam can make more than 500 round trips inside the synchrotron with a 1/e lifetime of 6.2 s. The synchrotron can find potential applications in low-energy collision and reaction experiments or in the field of precision measurements, such as the searches for electric dipole moment of elementary particles. PMID:27600539

  16. Centrality determination in heavy-ion collisions with the CBM experiment

    NASA Astrophysics Data System (ADS)

    Klochkov; Selyuzhenkov, I.; CBM collaboration

    2017-01-01

    The size and evolution of the medium created in a heavy-ion collision depends on collision geometry. Experimentally collisions can be characterized by the measured particle multiplicities around midrapidity or by the energy measured in the forward rapidity region, which is sensitive to the spectator fragments. In the Compressed Baryonic Matter (CBM) experiment at the future Facility for Antiproton and Ion Research (FAIR) the multiplicity of produced particles is measured with the silicon tracking system (STS). The projectile spectator detector (PSD) measures the energy of spectator fragments. We present the procedure of collision centrality determination in CBM and its performance using the PSD and the STS information.

  17. Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

    NASA Technical Reports Server (NTRS)

    Eaton, L. R.; Greco, E. V.

    1973-01-01

    The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

  18. Estimates of the collision symmetry planes in HADES experiment at GSI

    NASA Astrophysics Data System (ADS)

    Zaytsev, A. S.; Selyuzhenkov, I.

    2017-01-01

    Estimate of the collision symmetry planes is a crucial part of the anisotropic flow analysis in heavy-ion collisions. HADES experiment at GSI has different possibilities for symmetry plane estimation. In this letter different methods of the symmetry plane resolution calculation are compared and the differences are explained in terms of non-flow contribution.

  19. MHD Models and Laboratory Experiments of Jets

    NASA Astrophysics Data System (ADS)

    Gardiner, T. A.; Frank, A.; Blackman, E. G.; Lebedev, S. V.; Chittenden, J. P.; Ampleford, D.; Bland, S. N.; Ciardi, A.; Sherlock, M.; Haines, M. G.

    Jet research has long relied upon a combination of analytical, observational and numerical studies to elucidate the complex phenomena involved. One element missing from these studies (which other physical sciences utilize) is the controlled experimental investigation of such systems. With the advent of high-power lasers and fast Z-pinch machines it is now possible to experimentally study similar systems in a laboratory setting. Such investigations can contribute in two useful ways. They can be used for comparison with numerical simulations as a means to validate simulation codes. More importantly, however, such investigations can also be used to complement other jet research, leading to fundamentally new knowledge. In the first part of this article, we analyze the evolution of magnetized wide-angle winds in a collapsing environment. We track the ambient and wind mass separately and describe a physical mechanism by which an ionized central wind can entrain the ambient gas giving rise to internal shells of molecular material on short time scales. The formation of internal shells in molecular outflows has been found to be an important ingredient in describing the observations of convex spurs in P-V diagrams (Hubble wedges in M-V diagrams). In the second part, we present astrophysically relevant experiments in which supersonic jets are created using a conical wire array Z-pinch. The conically convergent flow generates a standing shock around the axis which collimates the flow into a Mach ~ 30 jet. The jet formation process is closely related to the work of Cantó et al. (1988) for hydrodynamic jet collimation. The influence of radiative cooling on collimation and stability is studied by varying the wire material (Al, Fe, and W).

  20. The laboratory experience in introductory physics courses

    NASA Astrophysics Data System (ADS)

    Di Stefano, Maria C.

    1997-03-01

    The last two decades or so have witnessed intense efforts to improve the teaching and learning of physics. Scholarly studies have provided the grounding for many projects which reform the structure of introductory courses. A number of these innovations, however, are resource intensive, or depend on the ability to introduce changes in areas which are beyond the control of the faculty (e.g., scheduling), thus inhibiting their implementation. An alternative strategy that overcomes these obstacles is to modify the nature of the laboratory experience (a component that practically nobody disputes is an essential part of the introductory course), to provide hands-on learning opportunities that differ from the traditional "follow-this-recipe-to-verify-this-law" approach. I have chosen to implement a variety of activities that support the overall objectives of the course: developing conceptual understanding and transferable skills, and providing practice in the ways scientists actually do science. Given the audience in this two-semester, algebra-based course, mostly biology majors and pre-professionals (health-related careers, such as medicine, physical therapy, and veterinary), these goals were identified as the most important and lasting contribution that a physics course can make to the students intellectual development. I offer here examples of the types of hands on activities that I have implemented, organized for the sake of this presentation in four rather loose categories, depending on which subset of the course objectives the activities mostly address: self-designed lab activities, discussion of demo-type activities, building concepts from simple to complex, and out-of-lab physical phenomena.

  1. Density Estimations in Laboratory Debris Flow Experiments

    NASA Astrophysics Data System (ADS)

    Queiroz de Oliveira, Gustavo; Kulisch, Helmut; Malcherek, Andreas; Fischer, Jan-Thomas; Pudasaini, Shiva P.

    2016-04-01

    Bulk density and its variation is an important physical quantity to estimate the solid-liquid fractions in two-phase debris flows. Here we present mass and flow depth measurements for experiments performed in a large-scale laboratory set up. Once the mixture is released and it moves down the inclined channel, measurements allow us to determine the bulk density evolution throughout the debris flow. Flow depths are determined by ultrasonic pulse reflection, and the mass is measured with a total normal force sensor. The data were obtained at 50 Hz. The initial two phase material was composed of 350 kg debris with water content of 40%. A very fine pebble with mean particle diameter of 3 mm, particle density of 2760 kg/m³ and bulk density of 1400 kg/m³ in dry condition was chosen as the solid material. Measurements reveal that the debris bulk density remains high from the head to the middle of the debris body whereas it drops substantially at the tail. This indicates lower water content at the tail, compared to the head and the middle portion of the debris body. This means that the solid and fluid fractions are varying strongly in a non-linear manner along the flow path, and from the head to the tail of the debris mass. Importantly, this spatial-temporal density variation plays a crucial role in determining the impact forces associated with the dynamics of the flow. Our setup allows for investigating different two phase material compositions, including large fluid fractions, with high resolutions. The considered experimental set up may enable us to transfer the observed phenomena to natural large-scale events. Furthermore, the measurement data allows evaluating results of numerical two-phase mass flow simulations. These experiments are parts of the project avaflow.org that intends to develop a GIS-based open source computational tool to describe wide spectrum of rapid geophysical mass flows, including avalanches and real two-phase debris flows down complex natural

  2. First experiments probing the collision of parallel magnetic fields using laser-produced plasmas

    SciTech Connect

    Rosenberg, M. J.; Li, C. K.; Fox, W.; Igumenshchev, I.; Seguin, F. H.; Town, R. P.; Frenje, J. A.; Stoeckl, C.; Glebov, V.; Petrasso, R. D.

    2015-04-08

    Novel experiments to study the strongly-driven collision of parallel magnetic fields in β~10, laser-produced plasmas have been conducted using monoenergetic proton radiography. These experiments were designed to probe the process of magnetic flux pileup, which has been identified in prior laser-plasma experiments as a key physical mechanism in the reconnection of anti-parallel magnetic fields when the reconnection inflow is dominated by strong plasma flows. In the present experiments using colliding plasmas carrying parallel magnetic fields, the magnetic flux is found to be conserved and slightly compressed in the collision region. Two-dimensional (2D) particle-in-cell (PIC) simulations predict a stronger flux compression and amplification of the magnetic field strength, and this discrepancy is attributed to the three-dimensional (3D) collision geometry. Future experiments may drive a stronger collision and further explore flux pileup in the context of the strongly-driven interaction of magnetic fields.

  3. First experiments probing the collision of parallel magnetic fields using laser-produced plasmas

    SciTech Connect

    Rosenberg, M. J. Li, C. K.; Séguin, F. H.; Frenje, J. A.; Petrasso, R. D.; Fox, W.; Igumenshchev, I.; Stoeckl, C.; Glebov, V.; Town, R. P. J.

    2015-04-15

    Novel experiments to study the strongly-driven collision of parallel magnetic fields in β ∼ 10, laser-produced plasmas have been conducted using monoenergetic proton radiography. These experiments were designed to probe the process of magnetic flux pileup, which has been identified in prior laser-plasma experiments as a key physical mechanism in the reconnection of anti-parallel magnetic fields when the reconnection inflow is dominated by strong plasma flows. In the present experiments using colliding plasmas carrying parallel magnetic fields, the magnetic flux is found to be conserved and slightly compressed in the collision region. Two-dimensional (2D) particle-in-cell simulations predict a stronger flux compression and amplification of the magnetic field strength, and this discrepancy is attributed to the three-dimensional (3D) collision geometry. Future experiments may drive a stronger collision and further explore flux pileup in the context of the strongly-driven interaction of magnetic fields.

  4. Do-It-Yourself Experiments for the Instructional Laboratory

    ERIC Educational Resources Information Center

    Craig, Norman C.; Hill, Cortland S.

    2012-01-01

    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…

  5. Operational Amplifier Experiments for the Chemistry Laboratory.

    ERIC Educational Resources Information Center

    Braun, Robert D.

    1996-01-01

    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)

  6. Laboratory Experiments for Network Security Instruction

    ERIC Educational Resources Information Center

    Brustoloni, Jose Carlos

    2006-01-01

    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…

  7. Solitons Experience for Black Hole Production in Ultrarelativistic Particle Collisions

    NASA Astrophysics Data System (ADS)

    Aref'eva, I. Ya.

    2013-06-01

    We discuss the analogy between soliton scattering in quantum field theory and black hole/wormholes (BH/WH) production in ultrarelativistic particle collisions in gravity. It is a common wisdom of the current paradigm suggests that BH/WH formation in particles collisions will happen when a center-mass energy of colliding particles is sufficiently above the Planck scale (the transplanckian region) and the BH/WH production can be estimated by the classical geometrical cross section. We compare the background of this paradigm with the functional integral method to scattering amplitudes and, in particular, we stress the analogy of the BH production in collision of ultrarelativistic particle and appearance of breathers poles in the scattering amplitudes in the Sin-Gordon model.

  8. Solitons Experience for Black Hole Production in Ultrarelativistic Particle Collisions

    NASA Astrophysics Data System (ADS)

    Ya. Aref'eva, I.

    2012-11-01

    We discuss the analogy between soliton scattering in quantum field theory and black hole/wormholes (BH/WH) production in ultrarelativistic particle collisions in gravity. It is a common wisdom of the current paradigm suggests that BH/WH formation in particles collisions will happen when a center-mass energy of colliding particles is sufficiently above the Planck scale (the transplanckian region) and the BH/WH production can be estimated by the classical geometrical cross section. We compare the background of this paradigm with the functional integral method to scattering amplitudes and, in particular, we stress the analogy of the BH production in collision of ultrarelativistic particle and appearance of breathers poles in the scattering amplitudes in the Sin-Gordon model.

  9. Numerical Geodynamic Experiments of Continental Collision: Past and Present

    NASA Astrophysics Data System (ADS)

    Gray, Robert

    Research explores deep continental lithosphere (i.e., the continental lower crust and mantle lithosphere) deformation during continental collision. I found that depending on the composition/rheology of the crust and the amount of radiogenic heat production in the crust, three dominant modes of mantle lithosphere deformation evolve under Neoarchean-like conditions: (1) a pure-shear thickening style; (2) an imbrication style; (3) and a "flat-subduction" style. The imbrication and the flat-subduction styles result in the emplacement of "plate-like" mantle lithosphere at depths between 200 km and 325 km. The imbrication style behavior shifts to the "flat-subduction" style behavior after a crustal inversion event. I investigated mature Phanerozoic-style collision and found that it is sensitive to mantle lithosphere density, mantle lithosphere yield stress, lower-crustal strength and to the presence of phase change-related density changes in the lower crust. The early stages of collision are accommodated by subduction of lower crust and mantle lithosphere along a discrete shear zone beneath the overriding plate. Next, the subducting lower crust and mantle lithosphere retreat from the collision zone, permitting the sub-lithospheric mantle to upwell and intrude the overriding plate. Next, the lower crust and mantle lithosphere of the overriding plate delaminate from the overlying crust. This process produces plateau-like uplift. These modeling results are interpreted in the context of available geological and geophysical observables for the Himalayan-Tibetan orogen. I quantitatively investigated the effects that sediment deposition may have on continental lithosphere deformation during collision. In the absence of sedimentation, the early stages of collision are accommodated by subduction of lower crust and mantle lithosphere beneath the overriding plate. Next, the subducting lower crust and mantle lithosphere retreat from the collision zone. This permits the sub

  10. The Unstructured Student-Designed Research Type of Laboratory Experiment.

    ERIC Educational Resources Information Center

    Macias-Machin, Agustin; And Others

    1990-01-01

    Discusses the use of an individually designed experiment for a chemical engineering laboratory course. Lists main ideas of the method. Provides an example of the experiment including ways to answer the questions and extensions. (YP)

  11. Practical Enzyme Kinetics: A Biochemical Laboratory Experiment.

    ERIC Educational Resources Information Center

    Rowe, H. Alan; Brown, Morris

    1988-01-01

    Describes an experiment that provides a fundamental understanding of the kinetics of the enzyme papain. Discusses background, materials, procedures and results. Mentions analogous experiments that can be conducted with enzymatic contact-lens cleaning solutions. (CW)

  12. Principles of Radio: A Laboratory Experiment

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2002-01-01

    An experiment is proposed for learning the principles of radio. A simple radio receiver illustrates amplitude modulation and demodulation, the selectivity of a receiver and the features of a directional antenna. Both normal and computerized versions of the experiment are described. The computerized experiment employs the "ScienceWorkshop"…

  13. Laboratory Experiences in Marine Biology, Student Edition.

    ERIC Educational Resources Information Center

    Raimist, Roger J.

    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…

  14. Work Experience of Certified Laboratory Assistants.

    ERIC Educational Resources Information Center

    National Council on Medical Technology Education, Bethesda, MD.

    Questionnaires concerning the nature of work performed and the work setting, plans for continuing formal education, and opinions regarding the relevancy of training received were sent to all individuals (3,282) certified by the Board of Certified Laboratory Assistants (CLA's) since certification began in 1965. Some findings from the 970 returned…

  15. Laboratory Experiment on Electrokinetic Remediation of Soil

    ERIC Educational Resources Information Center

    Elsayed-Ali, Alya H.; Abdel-Fattah, Tarek; Elsayed-Ali, Hani E.

    2011-01-01

    Electrokinetic remediation is a method of decontaminating soil containing heavy metals and polar organic contaminants by passing a direct current through the soil. An undergraduate chemistry laboratory is described to demonstrate electrokinetic remediation of soil contaminated with copper. A 30 cm electrokinetic cell with an applied voltage of 30…

  16. A Meaningful Experience in Laboratory Investigation

    ERIC Educational Resources Information Center

    Szinai, S. S.; Szinai, N.

    1976-01-01

    The framework of the course "Problems in Pharmaceutical Chemistry" was used to give second- and third-year pharmacy students at the University of Florida an opportunity to obtain an insight into the workings of laboratories dealing with drug-related problems. Goals, outline, and an illustrative project for the course are described. (LBH)

  17. Laboratory High-velocity, Laser-Driven, Magnetized, Collision-less Flows

    NASA Astrophysics Data System (ADS)

    Pepin, Henri; Higginson, D.; Korneev, Ph.; Beard, J.; Chen, S. N.; Grech, M.; Gremillet, L.; D'Humières, E.; Pikuz, S.; Pollock, B.; Ruyer, C.; Riquier, R.; Fuchs, J.

    2015-11-01

    Understanding the mechanism leading to the acceleration of cosmic-ray particles up to extremely high-energies is an outstanding problem in astrophysics. This acceleration is thought to be linked to the collision-less shocks formed by the collision of energetic magnetized astrophysical outflows such as supernovae remnants and gamma-ray bursts. To gain insight on these particle accelerators, we have performed experiments on the Titan laser (60J/beam, 650fs). By irradiating opposing targets we launch two counter-streaming beams, embedded in an external 20T B-field. We observe a density increase in the middle of the streams and a proton acceleration at double the energy without external field. Particle-in-cell simulations show that the expansion of the beams causes a compression of the external B-field up to 500T, which is strong enough to reflect electrons from the strong field region. This creates a charge-separation and causes the development of strong E-fields which accelerates the ions at large energies, consistent with the experiment.

  18. Dielectron Production in Heavy Ions Collisions: the HADES Experiment

    SciTech Connect

    J. A. Garzon; H. Alvarez-Pol; I. Duran; C. Fernandez; B. Fuentes; R. Lorenzo; M. Sanchez; A. Vazquez-Cardesin

    1999-12-31

    HADES (High Acceptance Di-Electron Spectrometer) is being built at UNILAC-SIS in Darmstadt with the main purpose of studying the production of dilepton pairs in nucleus-nucleus collisions at energies of 1AGeV. The spectrometer is briefly described, and the responsibilities of the group from the University of Santiago de Compostela are discussed.

  19. A Laboratory Experiment on the Statistical Theory of Nuclear Reactions

    ERIC Educational Resources Information Center

    Loveland, Walter

    1971-01-01

    Describes an undergraduate laboratory experiment on the statistical theory of nuclear reactions. The experiment involves measuring the relative cross sections for formation of a nucleus in its meta stable excited state and its ground state by applying gamma-ray spectroscopy to an irradiated sample. Involves 3-4 hours of laboratory time plus…

  20. Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

    NASA Technical Reports Server (NTRS)

    Williams, Jeffrey P.; Rallo, Rosemary A.

    1987-01-01

    A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for laboratory experiments, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

  1. Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

    NASA Technical Reports Server (NTRS)

    Williams, Jeffrey P.; Rallo, Rosemary A.

    1987-01-01

    A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for a laboratory experiment, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

  2. Industrial Hygiene Laboratory accreditation: The JSC experience

    NASA Technical Reports Server (NTRS)

    Fadner, Dawn E.

    1993-01-01

    The American Industrial Hygiene Association (AIHA) is a society of professionals dedicated to the health and safety of workers and community. With more than 10,000 members, the AIHA is the largest international association serving occupational and environmental health professionals practicing industrial hygiene in private industry, academia, government, labor, and independent organizations. In 1973, AIHA developed a National Industrial Hygiene Laboratory Accreditation Program. The purposes of this program are shown.

  3. Recycle with Heating: A Laboratory Experiment.

    ERIC Educational Resources Information Center

    Foord, A.; Mason, G.

    1985-01-01

    Describes an apparatus (built from domestic plumbing pipes and fittings) that uses only water and electricity (as consumables) to investigate basic mass and heat balances in a system with recycle. Also describes experiments using the apparatus. (JN)

  4. Buffer Capacity: An Undergraduate Laboratory Experiment.

    ERIC Educational Resources Information Center

    Russo, Steven O.; Hanania, George I. H.

    1987-01-01

    Describes a quantitative experiment designed to demonstrate buffer action and the measurement of buffer capacity. Discusses how to make acetate buffers, determine their buffer capacity, plot the capacity/pH curve, and interpret the data obtained. (TW)

  5. Improving Target Characterization for Laboratory Astrophysics Experiments

    NASA Astrophysics Data System (ADS)

    Marion, D. C.; Grosskopf, M. J.; Kuranz, C. C.; Drake, R. P.; Huntington, C. M.; Doss, F. W.; Krauland, C. M.; Distefano, C. A.

    2010-11-01

    We have fabricated and characterized targets for laboratory astrophysics since 2003, and have made improvements focusing on characterizing particular target features and their variances. Examples of measurements include machined features, material thickness and uniformity, location and thickness of glue, and mating conditions between adjacent materials. Measurements involve new technology and characterization methods, such as pre-shot radiography. More accurate characterization also leads to improvements in fabrication techniques, and helps integrate new technology into our build process. Quantifying variances more precisely also helps us better evaluate each fabrication method for both accuracy and consistency. We present these characterization methods and their impact on fabrication. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via grant DEFC52- 08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-FG52-09NA29034.

  6. Laboratory experiments in integrated circuit fabrication

    NASA Technical Reports Server (NTRS)

    Jenkins, Thomas J.; Kolesar, Edward S.

    1993-01-01

    The objectives of the experiment are fourfold: to provide practical experience implementing the fundamental processes and technology associated with the science and art of integrated circuit (IC) fabrication; to afford the opportunity for the student to apply the theory associated with IC fabrication and semiconductor device operation; to motivate the student to exercise engineering decisions associated with fabricating integrated circuits; and to complement the theory of n-channel MOS and diffused devices that are presented in the classroom by actually fabricating and testing them. Therefore, a balance between theory and practice can be realized in the education of young engineers, whose education is often criticized as lacking sufficient design and practical content.

  7. Plasma kinetic effects on interfacial mix in settings relevant to inertial confinement fusion and laboratory experiments

    NASA Astrophysics Data System (ADS)

    Yin, L.; Albright, B. J.; Bergen, B.; Bowers, K. J.; Vold, E. L.; Molvig, K.; Fernández, J. C.; Bang, W.; Bradley, P. A.; Gautier, D. C.; Hamilton, C. E.; Palaniyappan, S.; Santiago Cordoba, M. A.; Hegelich, B. M.; Dyer, G.; Roycroft, R.

    2015-11-01

    Mixing of high-Z/low-Z interfaces in dense plasma media is a problem of importance for understanding mix in inertial confinement fusion experiments and recent experiments at the LANL Trident facility. In this presentation, we apply the VPIC particle-in-cell code with a binary collision model to explore kinetic effects of the atomic mixing. Comparisons are made to published analytic theory and hybrid modeling results and conditions are identified under which plasma kinetic behavior may lead to anomalously rapid atomic mixing. Work performed under the auspices of the U.S. DOE by the LANS, LLC, Los Alamos National Laboratory under Contract No. DE-AC52-06NA25396. Funding provided by the Los Alamos National Laboratory Directed Research and Development Program.

  8. Simple Laboratory Experiment for Illustrating Soil Respiration.

    ERIC Educational Resources Information Center

    Hattey, J. A.; Johnson, G. V.

    1997-01-01

    Describes an experiment to illustrate the effect of food source and added nutrients (N) on microbial activity in the soil. Supplies include air-dried soil, dried plant material, sources of carbon and nitrogen, a trap such as KOH, colored water, and a 500-mL Erlenmeyer flask. Includes a diagram of an incubation chamber to demonstrate microbial…

  9. Laboratory plate tectonics: a new experiment.

    PubMed

    Gans, R F

    1976-03-26

    A "continent" made of a layer of hexagonally packed black polyethylene spheres floating in clear silicon oil breaks into subcontinents when illuminated by an ordinary incandescent light bulb. This experiment may be a useful model of plate tectonics driven by horizontal temperature gradients. Measurements of the spreading rate are made to establish the feasibility of this model.

  10. The generation and amplification of intergalactic magnetic fields in analogue laboratory experiments with high power lasers

    NASA Astrophysics Data System (ADS)

    Gregori, G.; Reville, B.; Miniati, F.

    2015-11-01

    The advent of high-power laser facilities has, in the past two decades, opened a new field of research where astrophysical environments can be scaled down to laboratory dimensions, while preserving the essential physics. This is due to the invariance of the equations of magneto-hydrodynamics to a class of similarity transformations. Here we review the relevant scaling relations and their application in laboratory astrophysics experiments with a focus on the generation and amplification of magnetic fields in cosmic environment. The standard model for the origin of magnetic fields is a multi stage process whereby a vanishing magnetic seed is first generated by a rotational electric field and is then amplified by turbulent dynamo action to the characteristic values observed in astronomical bodies. We thus discuss the relevant seed generation mechanisms in cosmic environment including resistive mechanism, collision-less and fluid instabilities, as well as novel laboratory experiments using high power laser systems aimed at investigating the amplification of magnetic energy by magneto-hydrodynamic (MHD) turbulence. Future directions, including efforts to model in the laboratory the process of diffusive shock acceleration are also discussed, with an emphasis on the potential of laboratory experiments to further our understanding of plasma physics on cosmic scales.

  11. Millikan's oil-drop experiment as a remotely controlled laboratory

    NASA Astrophysics Data System (ADS)

    Eckert, Bodo; Gröber, Sebastian; Vetter, Martin; Jodl, Hans-Jörg

    2012-09-01

    The Millikan oil-drop experiment, to determine the elementary electrical charge e and the quantization of charge Q = n · e, is an essential experiment in physics teaching but it is hardly performed in class for several reasons. Therefore, we offer this experiment as a remotely controlled laboratory (RCL). We describe the interactivity of the experiment and the quality of measurements. The added value to offer the Millikan experiment as an RCL is pointed out.

  12. Symmetron dark energy in laboratory experiments.

    PubMed

    Upadhye, Amol

    2013-01-18

    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 μ~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 λ is < or approximately equal to 7.5.

  13. A Simple Photochemical Experiment for the Advanced Laboratory.

    ERIC Educational Resources Information Center

    Rosenfeld, Stuart M.

    1986-01-01

    Describes an experiment to provide students with: (1) an introduction to photochemical techniques and theory; (2) an experience with semimicro techniques; (3) an application of carbon-14 nuclear magnetic resonance; and (4) a laboratory with some qualities of a genuine experiment. These criteria are met in the photooxidation of 9,…

  14. Millikan's Oil-Drop Experiment as a Remotely Controlled Laboratory

    ERIC Educational Resources Information Center

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

    2012-01-01

    The Millikan oil-drop experiment, to determine the elementary electrical charge e and the quantization of charge Q = n [middle dot] e, is an essential experiment in physics teaching but it is hardly performed in class for several reasons. Therefore, we offer this experiment as a remotely controlled laboratory (RCL). We describe the interactivity…

  15. Catching Collisions in the LHC

    SciTech Connect

    Fruguiele, Claudia; Hirschauer, Jim

    2015-06-16

    Now that the Large Hadron Collider has officially turned back on for its second run, within every proton collision could emerge the next new discovery in particle physics. Learn how the detectors on the Compact Muon Solenoid, or CMS, experiment capture and track particles as they are expelled from a collision. Talking us through these collisions are Claudia Fruguiele and Jim Hirschauer of Fermi National Accelerator Laboratory, the largest U.S. institution collaborating on the LHC.

  16. Catching Collisions in the LHC

    ScienceCinema

    Fruguiele, Claudia; Hirschauer, Jim

    2016-07-12

    Now that the Large Hadron Collider has officially turned back on for its second run, within every proton collision could emerge the next new discovery in particle physics. Learn how the detectors on the Compact Muon Solenoid, or CMS, experiment capture and track particles as they are expelled from a collision. Talking us through these collisions are Claudia Fruguiele and Jim Hirschauer of Fermi National Accelerator Laboratory, the largest U.S. institution collaborating on the LHC.

  17. Laboratory modeling of ionospheric heating experiments

    NASA Astrophysics Data System (ADS)

    Starodubtsev, M. V.; Nazarov, V. V.; Gushchin, M. E.; Kostrov, A. V.

    2016-10-01

    Turbulent plasma processes, such as those which occur in the Earth's ionosphere during ionospheric heating by powerful radio waves, were studied under laboratory conditions, and new physical models of small-scale ionospheric turbulence are proposed as a result of these studies. It is shown here that the mechanism of small-scale plasma filamentation can be connected with the thermal self-channeling of Langmuir waves. During this process, Langmuir waves are guided by a plasma channel, which in turn is formed by the guided waves through a thermal plasma nonlinearity. The spectrum of the self-guided Langmuir waves exhibits sidebands whose features are similar to stimulated electromagnetic emission. We present two mechanisms of sideband generation. The first mechanism can be observed during the formation of the plasma channel and is connected with the parametric shift in the frequency of the self-channeling wave. The second mechanism is connected with the scattering of the self-channeling wave on the low-frequency eigenmodes of the plasma irregularity.

  18. Agreed Discoveries: Students' Negotiations in a Virtual Laboratory Experiment

    ERIC Educational Resources Information Center

    Karlsson, Goran; Ivarsson, Jonas; Lindstrom, Berner

    2013-01-01

    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…

  19. Pilot Experience of Teaching a History of Physics Laboratory

    ERIC Educational Resources Information Center

    Hoddeson, Lillian Hartmann

    1971-01-01

    Outlines laboratory activities designed to permit both majors and non-majors to perform crucial experiments in physics, using, when possible, replicas of original apparatus and copies of translations of original texts. (PR)

  20. Reaction Kinetics: An Experiment for Biochemistry and Organic Chemistry Laboratories.

    ERIC Educational Resources Information Center

    Ewing, Sheila

    1982-01-01

    Describes an experiment to examine the kinetics of carbamate decomposition and the effect of buffer catalysis on the reaction. Includes background information, laboratory procedures, evaluation of data, and teaching suggestions. (Author/JN)

  1. High Performance Liquid Chromatography Experiments to Undergraduate Laboratories

    ERIC Educational Resources Information Center

    Kissinger, Peter T.; And Others

    1977-01-01

    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)

  2. Laboratory Experiments on the Electrochemical Remediation of the Environment

    ERIC Educational Resources Information Center

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

    2004-01-01

    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.

  3. Analytical study of the Atmospheric Cloud Physics Laboratory (ACPL) experiments

    NASA Technical Reports Server (NTRS)

    Davis, M. H.

    1977-01-01

    The design specifications of the research laboratory as a Spacelab facility are discussed along with the types of planned experiments. These include cloud formation, freezing and scavenging, and electrical phenomena. A summary of the program conferences is included.

  4. Some Experiments with Biological Applications for the Elementary Laboratory

    ERIC Educational Resources Information Center

    Kammer, D. W.; Williams, J. A.

    1975-01-01

    Summarizes physics laboratory experiments with applications in the biological sciences. Includes the following topics: mechanics of the human arm, fluid flow in tubes, physics of learning, the electrocardiograph, nerve impulse conduction, and corrective lenses for eye defects. (Author/MLH)

  5. Will Allis Prize Talk: Electron Collisions - Experiment, Theory and Applications

    NASA Astrophysics Data System (ADS)

    Bartschat, Klaus

    2016-05-01

    Electron collisions with atoms, ions, and molecules represent one of the very early topics of quantum mechanics. In spite of the field's maturity, a number of recent developments in detector technology (e.g., the ``reaction microscope'' or the ``magnetic-angle changer'') and the rapid increase in computational resources have resulted in significant progress in the measurement, understanding, and theoretical/computational description of few-body Coulomb problems. Close collaborations between experimentalists and theorists worldwide continue to produce high-quality benchmark data, which allow for thoroughly testing and further developing a variety of theoretical approaches. As a result, it has now become possible to reliably calculate the vast amount of atomic data needed for detailed modelling of the physics and chemistry of planetary atmospheres, the interpretation of astrophysical data, optimizing the energy transport in reactive plasmas, and many other topics - including light-driven processes, in which electrons are produced by continuous or short-pulse ultra-intense electromagnetic radiation. In this talk, I will highlight some of the recent developments that have had a major impact on the field. This will be followed by showcasing examples, in which accurate electron collision data enabled applications in fields beyond traditional AMO physics. Finally, open problems and challenges for the future will be outlined. I am very grateful for fruitful scientific collaborations with many colleagues, and the long-term financial support by the NSF through the Theoretical AMO and Computational Physics programs, as well as supercomputer resources through TeraGrid and XSEDE.

  6. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Researchers perform tests at Kennedy Space Center. New facilities for such research will be provided at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  7. Location for the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This diagram shows the planned locations of the Space Experiment Research and Processing Laboratory (SERPL) and the Space Station Commerce Park at Kennedy Space Center. The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for the planned 400- acre commerce park.

  8. Establishing laboratory standards for biological flight experiments

    NASA Technical Reports Server (NTRS)

    Young, Ronald B.; Moriarity, Debra M.

    1989-01-01

    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.

  9. Carbonatisation of Weathered Peridotites in Laboratory Experiments

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

    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

  10. The Himalaya-Tibet System: A Natural laboratory for continental collision and seismogenesis

    NASA Astrophysics Data System (ADS)

    Meltzer, A.; Brown, L. D.; Song, X.

    2015-12-01

    The Himalaya-Tibet system remains one of the best places to study continental dynamics, mountain building, and nucleation of great earthquakes. Over the past several decades, numerous research projects have used the Himalaya and Tibet as a natural laboratory to investigate the process of continental collision. Much has been learned about the orogen, including the remarkable along-strike continuity of many features: the orogen's basic geology and structure, the morphology and drainages of the Himalayan arc, and the apparent symmetry of the syntaxes at either end. At the same time, numerous focused studies have also identified considerable spatial variability in the GPS field, seismicity, crust and mantle structure, magnitude and timing of exhumation, erosion, and strain. While much has been learned and many details revealed, significant questions about the Himalaya and Tibet remain and we lack integrated 4D models that explain observed complexity. The time is right for a community initiative to systematically integrate the breadth of data available to test and refine geodynamic models to illuminate the structure and 4-D evolution of the India-Asia collision at scales that account for both first order observations and lateral heterogeneity, link deep earth and surface processes, and address the geohazards associated with the collisional zone and surrounding areas. Any such effort requires community consensus on science goals, setting priorities regarding what's needed to make significant progress, and open access data. An effort of this scale needs to address the societal impacts of hazards associated with the India-Asia collisional system and engage international collaborations across the region. The April 2015 Mw 7.8 Gorkha, Nepal earthquake serves as the most recent reminder that the Himalaya-Tibet system is capable of producing large magnitude events, impacting lives, livelihoods, and the built environment. The 1950 Mw 8.6 Assam and 2008 Mw 7.9 Wenchuan

  11. Experiment definition phase shuttle laboratory LDRL 10.6 experiment

    NASA Technical Reports Server (NTRS)

    1974-01-01

    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.

  12. Upgrades for the STAR Experiment Slow Controls at Brookhaven National Laboratory

    NASA Astrophysics Data System (ADS)

    Ruiz, Samuel; Fujita, Jiro

    2016-09-01

    The STAR (Solenoidal Tracker at RHIC) experiment at Brookhaven National Laboratory studies the collisions of relativistic heavy ions. Some components of the control system for STAR have not changed since STAR became operational in 2000. The goal of this project is to upgrade the control system software for easier maintenance. The software upgrade also requires modernizing the hardware in some cases. A prototype for monitoring the Field Cage for the Time Projection Chamber (TPC) and a prototype for controlling the TPC front-end electronics using a programmable logic controller were developed. Newly developed software for the hygrometer to monitor the experiment environment was deployed at the experiment. Details about the software and hardware upgrades, as well as the developed prototypes will be presented.

  13. Electron transport and energy degradation in the ionosphere: Evaluation of the numerical solution, comparison with laboratory experiments and auroral observations

    NASA Technical Reports Server (NTRS)

    Lummerzheim, D.; Lilensten, J.

    1994-01-01

    Auroral electron transport calculations are a critical part of auroral models. We evaluate a numerical solution to the transport and energy degradation problem. The numerical solution is verified by reproducing simplified problems to which analytic solutions exist, internal self-consistency tests, comparison with laboratory experiments of electron beams penetrating a collision chamber, and by comparison with auroral observations, particularly the emission ratio of the N2 second positive to N2(+) first negative emissions. Our numerical solutions agree with range measurements in collision chambers. The calculated N(2)2P to N2(+)1N emission ratio is independent of the spectral characteristics of the incident electrons, and agrees with the value observed in aurora. Using different sets of energy loss cross sections and different functions to describe the energy distribution of secondary electrons that emerge from ionization collisions, we discuss the uncertainties of the solutions to the electron transport equation resulting from the uncertainties of these input parameters.

  14. Glycosidation of Methanol with Ribose: An Interdisciplinary Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Simon, Erin; Cook, Katie; Pritchard, Meredith R.; Stripe, Wayne; Bruch, Martha; Bendinskas, Kestutis

    2010-01-01

    This exercise provides students hands-on experience with the topics of glycosidation, hemiacetal and acetal formation, proton nuclear magnetic resonance ([superscript 1]H NMR) spectroscopy, and kinetic and thermodynamic product formation. In this laboratory experiment, the methyl acetal of ribose is synthesized, and the kinetic and thermodynamic…

  15. Freeze Drying of Fruits and Vegetables: A Laboratory Experiment.

    ERIC Educational Resources Information Center

    Noble, Richard D.

    1979-01-01

    Describes a laboratory experiment for freeze-drying fruits and vegetables which aims to expose college students to the principles of drying and simultaneous heat and mass transfer. The experimental apparatus, procedure of the experiment, and data analysis are also included. (HM)

  16. In Situ Techniques for Monitoring Electrochromism: An Advanced Laboratory Experiment

    ERIC Educational Resources Information Center

    Saricayir, Hakan; Uce, Musa; Koca, Atif

    2010-01-01

    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…

  17. First experiments probing the collision of parallel magnetic fields using laser-produced plasmas

    DOE PAGES

    Rosenberg, M. J.; Li, C. K.; Fox, W.; ...

    2015-04-08

    Novel experiments to study the strongly-driven collision of parallel magnetic fields in β~10, laser-produced plasmas have been conducted using monoenergetic proton radiography. These experiments were designed to probe the process of magnetic flux pileup, which has been identified in prior laser-plasma experiments as a key physical mechanism in the reconnection of anti-parallel magnetic fields when the reconnection inflow is dominated by strong plasma flows. In the present experiments using colliding plasmas carrying parallel magnetic fields, the magnetic flux is found to be conserved and slightly compressed in the collision region. Two-dimensional (2D) particle-in-cell (PIC) simulations predict a stronger flux compressionmore » and amplification of the magnetic field strength, and this discrepancy is attributed to the three-dimensional (3D) collision geometry. Future experiments may drive a stronger collision and further explore flux pileup in the context of the strongly-driven interaction of magnetic fields.« less

  18. The student perspective of high school laboratory experiences

    NASA Astrophysics Data System (ADS)

    Lambert, R. Mitch

    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?

  19. Wiki Laboratory Notebooks: Supporting Student Learning in Collaborative Inquiry-Based Laboratory Experiments

    ERIC Educational Resources Information Center

    Lawrie, Gwendolyn Angela; Grøndahl, Lisbeth; Boman, Simon; Andrews, Trish

    2016-01-01

    Recent examples of high-impact teaching practices in the undergraduate chemistry laboratory that include course-based undergraduate research experiences and inquiry-based experiments require new approaches to assessing individual student learning outcomes. Instructors require tools and strategies that can provide them with insight into individual…

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

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

    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.

  1. Operating Experience of the Tritium Laboratory at CRL

    SciTech Connect

    Gallagher, C.L.; McCrimmon, K.D.

    2005-07-15

    The Chalk River Laboratories Tritium Laboratory has been operating safely and reliably for over 20 years. Safe operations are achieved through proper management, supervision, training and using approved operating procedures and techniques. Reliability is achieved through appropriate equipment selection, routine equipment surveillance testing and routine preventative maintenance. This paper summarizes the laboratory's standard operating protocols and formal compliance programs followed to ensure safe operations. The paper will also review the general set-up of the laboratory and will focus on the experience gained with the operation of various types of equipment such as tritium monitors, tritium analyzers, pumps, purification systems and other systems used in the laboratory during its 20 years of operation.

  2. The Binary Collision-Induced Second Overtone Band of Gaseous Hydrogen: Modelling and Laboratory Measurements

    NASA Technical Reports Server (NTRS)

    Brodbeck, C.; Bouanich, J.-P.; Nguyen, Van Thanh; Borysow, Aleksandra

    1999-01-01

    Collision-induced absorption (CIA) is the major source of the infrared opacity of dense planetary atmospheres which are composed of nonpolar molecules. Knowledge of CIA absorption spectra of H2-H2 pairs is important for modelling the atmospheres of planets and cold stars that are mainly composed of hydrogen. The spectra of hydrogen in the region of the second overtone at 0.8 microns have been recorded at temperatures of 298 and 77.5 K for gas densities ranging from 100 to 800 amagats. By extrapolation to zero density of the absorption coefficient measured every 10 cm(exp -1) in the spectral range from 11100 to 13800 cm(exp -1), we have determined the binary absorption coefficient. These extrapolated measurements are compared with calculations based on a model that was obtained by using simple computer codes and lineshape profiles. In view of the very weak absorption of the second overtone band, we find the agreement between results of the model and experiment to be reasonable.

  3. The Suborbital Particle Aggregation and Collision Experiment (SPACE): studying the collision behavior of submillimeter-sized dust aggregates on the suborbital rocket flight REXUS 12.

    PubMed

    Brisset, Julie; Heißelmann, Daniel; Kothe, Stefan; Weidling, René; Blum, Jürgen

    2013-09-01

    The Suborbital Particle Aggregation and Collision Experiment (SPACE) is a novel approach to study the collision properties of submillimeter-sized, highly porous dust aggregates. The experiment was designed, built, and carried out to increase our knowledge about the processes dominating the first phase of planet formation. During this phase, the growth of planetary precursors occurs by agglomeration of micrometer-sized dust grains into aggregates of at least millimeters to centimeters in size. However, the formation of larger bodies from the so-formed building blocks is not yet fully understood. Recent numerical models on dust growth lack a particular support by experimental studies in the size range of submillimeters, because these particles are predicted to collide at very gentle relative velocities of below 1 cm/s that can only be achieved in a reduced-gravity environment. The SPACE experiment investigates the collision behavior of an ensemble of silicate-dust aggregates inside several evacuated glass containers which are being agitated by a shaker to induce the desired collisions at chosen velocities. The dust aggregates are being observed by a high-speed camera, allowing for the determination of the collision properties of the protoplanetary dust analog material. The data obtained from the suborbital flight with the REXUS (Rocket Experiments for University Students) 12 rocket will be directly implemented into a state-of-the-art dust growth and collision model.

  4. The suborbital particle aggregation and collision experiment (SPACE): Studying the collision behavior of submillimeter-sized dust aggregates on the suborbital rocket flight REXUS 12

    NASA Astrophysics Data System (ADS)

    Brisset, Julie; Heißelmann, Daniel; Kothe, Stefan; Weidling, René; Blum, Jürgen

    2013-09-01

    The Suborbital Particle Aggregation and Collision Experiment (SPACE) is a novel approach to study the collision properties of submillimeter-sized, highly porous dust aggregates. The experiment was designed, built, and carried out to increase our knowledge about the processes dominating the first phase of planet formation. During this phase, the growth of planetary precursors occurs by agglomeration of micrometer-sized dust grains into aggregates of at least millimeters to centimeters in size. However, the formation of larger bodies from the so-formed building blocks is not yet fully understood. Recent numerical models on dust growth lack a particular support by experimental studies in the size range of submillimeters, because these particles are predicted to collide at very gentle relative velocities of below 1 cm/s that can only be achieved in a reduced-gravity environment. The SPACE experiment investigates the collision behavior of an ensemble of silicate-dust aggregates inside several evacuated glass containers which are being agitated by a shaker to induce the desired collisions at chosen velocities. The dust aggregates are being observed by a high-speed camera, allowing for the determination of the collision properties of the protoplanetary dust analog material. The data obtained from the suborbital flight with the REXUS (Rocket Experiments for University Students) 12 rocket will be directly implemented into a state-of-the-art dust growth and collision model.

  5. A Model for Designing Adaptive Laboratory Evolution Experiments.

    PubMed

    LaCroix, Ryan A; Palsson, Bernhard O; Feist, Adam M

    2017-04-15

    The occurrence of mutations is a cornerstone of the evolutionary theory of adaptation, capitalizing on the rare chance that a mutation confers a fitness benefit. Natural selection is increasingly being leveraged in laboratory settings for industrial and basic science applications. Despite increasing deployment, there are no standardized procedures available for designing and performing adaptive laboratory evolution (ALE) experiments. Thus, there is a need to optimize the experimental design, specifically for determining when to consider an experiment complete and for balancing outcomes with available resources (i.e., laboratory supplies, personnel, and time). To design and to better understand ALE experiments, a simulator, ALEsim, was developed, validated, and applied to the optimization of ALE experiments. The effects of various passage sizes were experimentally determined and subsequently evaluated with ALEsim, to explain differences in experimental outcomes. Furthermore, a beneficial mutation rate of 10(-6.9) to 10(-8.4) mutations per cell division was derived. A retrospective analysis of ALE experiments revealed that passage sizes typically employed in serial passage batch culture ALE experiments led to inefficient production and fixation of beneficial mutations. ALEsim and the results described here will aid in the design of ALE experiments to fit the exact needs of a project while taking into account the resources required and will lower the barriers to entry for this experimental technique.IMPORTANCE ALE is a widely used scientific technique to increase scientific understanding, as well as to create industrially relevant organisms. The manner in which ALE experiments are conducted is highly manual and uniform, with little optimization for efficiency. Such inefficiencies result in suboptimal experiments that can take multiple months to complete. With the availability of automation and computer simulations, we can now perform these experiments in an optimized

  6. Argumentation in the Chemistry Laboratory: Inquiry and Confirmatory Experiments

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

    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.

  7. Results from Cu+Au collisions at 200 GeV in PHENIX Experiment

    SciTech Connect

    Berdnikov, Ya. A.; Kotov, D. O.; Safonov, A. S.; Ivanishchev, D. A.; Riabov, V. G.; Riabov, Yu. G.; Samsonov, V. M.

    2016-01-22

    Collisions of asymmetric nuclei (Cu+Au) differ essentially from the case of symmetric nuclei (Cu+Cu, Au+Au) collisions in the geometry of overlap region. This leads to a number of consequences, which provide more absolute and accurate information about fundamental properties of matter under extreme conditions. Nuclear modification factors for π-mesons in Cu+Au interactions at 200 GeV were measured in PHENIX Experiment at RHIC. New experimental data on measurement of flows of different order (v{sub 1}, v{sub 2}) for light hadrons in Cu+Au interactions at 200 GeV will be discussed in this paper.

  8. Conceptual change in an organic chemistry laboratory: A comparison of computer simulations and traditional laboratory experiments

    NASA Astrophysics Data System (ADS)

    Gaddis, Barbara A.

    2001-12-01

    This quasi-experimental research study examined the effect of computer simulations and hands-on laboratory experiments in enhancing conceptual understanding and alleviating misconceptions of organic chemistry reaction mechanisms. Subjects were sixty-nine sophomore-level organic chemistry students enrolled in four laboratory sections. Laboratory sections were stratified across instructor and randomly assigned to serve as a control or treatment laboratory. Students in the control group performed all hands-on experiments. Students in the treatment group performed hands-on experiments for the first and last part of the semester but performed computer simulations for a five-week period in the middle of the semester. Prior to treatment, groups were equivalent with respect to academic orientation, motivation, formal reasoning ability, and spatial visualization ability. Fifteen common misconceptions held by beginning organic chemistry students were identified from the Covalent Bonding and Structures Test. At the end of the semester, thirteen of these misconceptions persisted. Molecular geometry was the only category of misconceptions that significantly improved as a result of computer simulations, F(1,58) = 6.309, p = .015. No significant differential change was observed in misconceptions about bond polarity, molecular polarity, intermolecular forces, lattice structures, or the octet rule. Computer simulations were found to result in significantly greater conceptual understanding of organic chemistry reactions on two of the experiments, Stereochemistry, F(1,55) = 6.174, p = .016, and Nucleophilic Substitution, F(1,57) = 6.093, p = .017. The other three experiments, Infrared Spectroscopy, Elimination, and Oxymercuration, did not show a significant differential effect between types of laboratory experiences. No significant differences were observed on long-term retention of concepts. Overall conclusions from the study are that neither computer simulations nor hands

  9. On integrating LES and laboratory turbulent flow experiments

    SciTech Connect

    Grinstein, Fernando Franklin

    2008-01-01

    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.

  10. On integrating large eddy simulation and laboratory turbulent flow experiments.

    PubMed

    Grinstein, Fernando F

    2009-07-28

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2003-03-01

    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.

  12. Development of sensorial experiments and their implementation into undergraduate laboratories

    NASA Astrophysics Data System (ADS)

    Bromfield Lee, Deborah Christina

    "Visualization" of chemical phenomena often has been limited in the teaching laboratories to the sense of sight. We have developed chemistry experiments that rely on senses other than eyesight to investigate chemical concepts, make quantitative determinations, and familiarize students with chemical techniques traditionally designed using only eyesight. Multi-sensory learning can benefit all students by actively engaging them in learning through stimulation or an alternative way of experiencing a concept or ideas. Perception of events or concepts usually depends on the information from the different sensory systems combined. The use of multi-sensory learning can take advantage of all the senses to reinforce learning as each sense builds toward a more complete experience of scientific data. Research has shown that multi-sensory representations of scientific phenomena is a valuable tool for enhancing understanding of chemistry as well as displacing misconceptions through experience. Multi-sensory experiences have also been shown to enrich memory performance. There are few experiments published which utilize multiple senses in the teaching laboratory. The sensorial experiments chosen were conceptually similar to experiments currently performed in undergraduate laboratories; however students collect different types of data using multi-sensory observations. The experiments themselves were developed by using chemicals that would provide different sensory changes or capitalizing on sensory observations that were typically overlooked or ignored and obtain similar and precise results as in traditional experiments. Minimizing hazards and using safe practices are especially essential in these experiments as students utilize senses traditionally not allowed to be used in the laboratories. These sensorial experiments utilize typical equipment found in the teaching laboratories as well as inexpensive chemicals in order to aid implementation. All experiments are rigorously tested

  13. Large-size space laboratory for biological orbit experiments.

    PubMed

    Kondyurin, A

    2001-01-01

    The study of space factors on living systems has great interest and long-term experiments during orbital flight will be important tool for increasing our knowledge. Realization of such experiments is limited by constraints of modern space stations. A new technology of large-size space laboratory for biological experiments has been developed on the basis of polymerization techniques. Using this technique there are no limits of form and size of laboratory for a space station that will permit long term experiments on Earth orbit with plants and animals in sufficient volume for creation of closed self-regulating ecological systems. The technology is based on experiments of the behavior of polymer materials in simulated free space conditions during the reaction of polymerization. The influences of space vacuum, sharp temperature changes and space plasma generated by galactic rays and Sun irradiation on chemical reaction were evaluated in their impact on liquid organic materials in laboratory conditions. The results of our study shows, that the chemical reaction is sensitive to such space factors. But we believe that the technology of polymerization could be used for the creation of space biological laboratories in Earth orbit in the near future.

  14. Combustion experiments in a zero-gravity laboratory

    NASA Technical Reports Server (NTRS)

    Cochran, T. H.

    1981-01-01

    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.

  15. Simulations of Laboratory Astrophysics Experiments using the CRASH code

    NASA Astrophysics Data System (ADS)

    Trantham, Matthew; Kuranz, Carolyn; Manuel, Mario; Keiter, Paul; Drake, R. P.

    2014-10-01

    Computer simulations can assist in the design and analysis of laboratory astrophysics experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport, electron heat conduction and laser ray tracing. This poster/talk will demonstrate some of the experiments the CRASH code has helped design or analyze including: Kelvin-Helmholtz, Rayleigh-Taylor, imploding bubbles, and interacting jet experiments. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via Grant DEFC52-08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0001840, and by the National Laser User Facility Program, Grant Number DE-NA0000850.

  16. How can laboratory plasma experiments contribute to space and &astrophysics?

    NASA Astrophysics Data System (ADS)

    Yamada, M.

    Plasma physics plays key role in a wide range of phenomena in the universe, from laboratory plasmas to the magnetosphere, the solar corona, and to the tenuous interstellar and intergalactic gas. Despite the huge difference in physical scales, there are striking similarities in plasma behavior of laboratory and space plasmas. Similar plasma physics problems have been investigated independently by both laboratory plasma physicists and astrophysicists. Since 1991, cross fertilization has been increased among laboratory plasma physicists and space physicists through meeting such as IPELS [Interrelationship between Plasma Experiments in the Laboratory and Space] meeting. The advances in laboratory plasma physics, along with the recent surge of astronomical data from satellites, make this moment ripe for research collaboration to further advance plasma physics and to obtain new understanding of key space and astrophysical phenomena. The recent NRC review of astronomy and astrophysics notes the benefit that can accrue from stronger connection to plasma physics. The present talk discusses how laboratory plasma studies can contribute to the fundamental understandings of the space and astrophysical phenomena by covering common key physics topics such as magnetic reconnection, dynamos, angular momentum transport, ion heating, and magnetic self-organization. In particular, it has recently been recognized that "physics -issue- dedicated" laboratory experiments can contribute significantly to the understanding of the fundamental physics for space-astrophysical phenomena since they can create fundamental physics processes in controlled manner and provide well-correlated plasma parameters at multiple plasma locations simultaneously. Such dedicated experiments not only can bring about better understanding of the fundamental physics processes but also can lead to findings of new physics principles as well as new ideas for fusion plasma confinement. Several dedicated experiments have

  17. Soap from Nutmeg: An Integrated Introductory Organic Chemistry Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    de Mattos, Marcio C. S.; Nicodem, David E.

    2002-01-01

    The extraction of trimyristin from nutmeg, its purification, and its conversion to a soap (sodium myristate) are described. Concepts such as the isolation of a natural product, recrystallization, identification of a solid, solubility, acidity and basicity, and organic reaction can be presented to students using integrated experiments in an introductory experimental chemistry laboratory. These experiments can easily be done in three class periods of four hours.

    See Letter re: this article.

  18. Laboratory experiments on magnetic reconnection and current systems

    NASA Astrophysics Data System (ADS)

    Stenzel, R. L.; Urrutia, J. M.; Gekelman, W.; Pfister, H.

    After a brief review of laboratory experiments involving magnetic reconnection a series of basic physics experiments on reconnection phenomena is described. These include magnetic annihilation, transport of magnetic energy by waves, stable and unstable current sheets, energy conversion mechanisms, and the role of global current systems vs. local reconnection processes. Current systems driven by electric fields resulting in particle flows are examined. Also, the role of a magnetic field component B(y) along the separator has been investigated.

  19. Raising environmental awareness through applied biochemistry laboratory experiments.

    PubMed

    Salman Ashraf, S

    2013-01-01

    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 is described that guides students to learn about the applicability of peroxidase enzymes to degrade organic dyes (as model pollutants) in simulated waste water. In addition to showing how enzymes can potentially be used for waste water remediation, various factors than can affect enzyme-based reactions such as pH, temperature, concentration of substrates/enzymes, and denaturants can also be tested. This "applied biotechnology" experiment was successfully implemented in an undergraduate biochemistry laboratory course to enhance students' learning of environmental issues as well important biochemistry concepts. Student survey confirmed that this laboratory experiment was successful in achieving the objectives of raising environmental awareness in students and illustrating the usefulness of chemistry in solving real-life problems. This experiment can be easily adopted in an introductory biochemistry laboratory course and taught as an inquiry-guided exercise.

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

    ERIC Educational Resources Information Center

    Kusek, J. C.

    1980-01-01

    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)

  1. Development of Sensorial Experiments and Their Implementation into Undergraduate Laboratories

    ERIC Educational Resources Information Center

    Bromfield Lee, Deborah Christina

    2009-01-01

    "Visualization" of chemical phenomena often has been limited in the teaching laboratories to the sense of sight. We have developed chemistry experiments that rely on senses other than eyesight to investigate chemical concepts, make quantitative determinations, and familiarize students with chemical techniques traditionally designed using only…

  2. Human Gene Discovery Laboratory: A Problem-Based Learning Experience

    ERIC Educational Resources Information Center

    Bonds, Wesley D., Sr.; Paolella, Mary Jane

    2006-01-01

    A single-semester elective combines Mendelian and molecular genetics in a problem-solving format. Students encounter a genetic disease scenario, construct a family pedigree, and try to confirm their medical diagnoses through laboratory experiences. Encouraged to generate ideas as they test their hypotheses, students realize the importance of data…

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

    ERIC Educational Resources Information Center

    Collins, David C.

    2011-01-01

    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…

  4. An Enzyme Kinetics Experiment for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

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

    2010-01-01

    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…

  5. Laboratory Experiment in Semiconductor Surface-Field Effects

    ERIC Educational Resources Information Center

    Goodman, F. R.; And Others

    1974-01-01

    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)

  6. Differentiating Biochemistry Course Laboratories Based on Student Experience

    ERIC Educational Resources Information Center

    Jakubowski, Henry V.

    2011-01-01

    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…

  7. Women's Experiences in the Engineering Laboratory in Japan

    ERIC Educational Resources Information Center

    Hosaka, Masako

    2014-01-01

    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…

  8. Computer Simulation of Laboratory Experiments: An Unrealized Potential.

    ERIC Educational Resources Information Center

    Magin, D. J.; Reizes, J. A.

    1990-01-01

    Discussion of the use of computer simulation for laboratory experiments in undergraduate engineering education focuses on work at the University of New South Wales in the instructional design and software development of a package simulating a heat exchange device. The importance of integrating theory, design, and experimentation is also discussed.…

  9. Synthesis of Methyl Cyclopentanecarboxylate: A Laboratory Experience in Carbon Rearrangement

    ERIC Educational Resources Information Center

    Orchard, Alexandra; Maniquis, Roxanne V.; Salzameda, Nicholas T.

    2016-01-01

    We present a novel guided inquiry second semester organic chemistry laboratory rearrangement experiment. Students performed the Favorskii Rearrangement to obtain methyl cyclopentanecarboxylate in good yields. The students learned about the individual steps of the Favorskii mechanism and were required to propose a complete reaction mechanism and…

  10. A Virtual Rock Physics Laboratory Through Visualized and Interactive Experiments

    NASA Astrophysics Data System (ADS)

    Vanorio, T.; Di Bonito, C.; Clark, A. C.

    2014-12-01

    As new scientific challenges demand more comprehensive and multidisciplinary investigations, laboratory experiments are not expected to become simpler and/or faster. Experimental investigation is an indispensable element of scientific inquiry and must play a central role in the way current and future generations of scientist make decisions. To turn the complexity of laboratory work (and that of rocks!) into dexterity, engagement, and expanded learning opportunities, we are building an interactive, virtual laboratory reproducing in form and function the Stanford Rock Physics Laboratory, at Stanford University. The objective is to combine lectures on laboratory techniques and an online repository of visualized experiments consisting of interactive, 3-D renderings of equipment used to measure properties central to the study of rock physics (e.g., how to saturate rocks, how to measure porosity, permeability, and elastic wave velocity). We use a game creation system together with 3-D computer graphics, and a narrative voice to guide the user through the different phases of the experimental protocol. The main advantage gained in employing computer graphics over video footage is that students can virtually open the instrument, single out its components, and assemble it. Most importantly, it helps describe the processes occurring within the rock. These latter cannot be tracked while simply recording the physical experiment, but computer animation can efficiently illustrate what happens inside rock samples (e.g., describing acoustic waves, and/or fluid flow through a porous rock under pressure within an opaque core-holder - Figure 1). The repository of visualized experiments will complement lectures on laboratory techniques and constitute an on-line course offered through the EdX platform at Stanford. This will provide a virtual laboratory for anyone, anywhere to facilitate teaching/learning of introductory laboratory classes in Geophysics and expand the number of courses

  11. Modeling Laboratory Astrophysics Experiments using the CRASH code

    NASA Astrophysics Data System (ADS)

    Trantham, Matthew; Drake, R. P.; Grosskopf, Michael; Bauerle, Matthew; Kruanz, Carolyn; Keiter, Paul; Malamud, Guy; Crash Team

    2013-10-01

    The understanding of high energy density systems can be advanced by laboratory astrophysics experiments. Computer simulations can assist in the design and analysis of these experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport and electron heat conduction. This poster/talk will demonstrate some of the experiments the CRASH code has helped design or analyze including: Radiative shocks experiments, Kelvin-Helmholtz experiments, Rayleigh-Taylor experiments, plasma sheet, and interacting jets experiments. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via grant DEFC52- 08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-NA0000850.

  12. BOW SHOCK FRAGMENTATION DRIVEN BY A THERMAL INSTABILITY IN LABORATORY ASTROPHYSICS EXPERIMENTS

    SciTech Connect

    Suzuki-Vidal, F.; Lebedev, S. V.; Pickworth, L. A.; Swadling, G. F.; Skidmore, J.; Hall, G. N.; Bennett, M.; Bland, S. N.; Burdiak, G.; De Grouchy, P.; Music, J.; Suttle, L.; Ciardi, A.; Rodriguez, R.; Gil, J. M.; Espinosa, G.; Hartigan, P.; Hansen, E.; Frank, A.

    2015-12-20

    The role of radiative cooling during the evolution of a bow shock was studied in laboratory-astrophysics experiments that are scalable to bow shocks present in jets from young stellar objects. The laboratory bow shock is formed during the collision of two counterstreaming, supersonic plasma jets produced by an opposing pair of radial foil Z-pinches driven by the current pulse from the MAGPIE pulsed-power generator. The jets have different flow velocities in the laboratory frame, and the experiments are driven over many times the characteristic cooling timescale. The initially smooth bow shock rapidly develops small-scale nonuniformities over temporal and spatial scales that are consistent with a thermal instability triggered by strong radiative cooling in the shock. The growth of these perturbations eventually results in a global fragmentation of the bow shock front. The formation of a thermal instability is supported by analysis of the plasma cooling function calculated for the experimental conditions with the radiative packages ABAKO/RAPCAL.

  13. Neutrino-atom collisions

    NASA Astrophysics Data System (ADS)

    Kouzakov, Konstantin A.; Studenikin, Alexander I.

    2016-05-01

    Neutrino-atom scattering provides a sensitive tool for probing nonstandard interactions of massive neutrinos in laboratory measurements. The ionization channel of this collision process plays an important role in experiments searching for neutrino magnetic moments. We discuss some theoretical aspects of atomic ionization by massive neutrinos. We also outline possible manifestations of neutrino electromagnetic properties in coherent elastic neutrino-nucleus scattering.

  14. Experiences and prospects of nuclear astrophysics in underground laboratories

    SciTech Connect

    Junker, M.

    2014-05-09

    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.

  15. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Original photo and caption dated June 22, 1988: 'A dwarf wheat variety known as Yecoro Rojo flourishes in KSC's Biomass Production Chamber. Researchers are gathering information on the crop's ability to produce food, water and oxygen, and then remove carbon dioxide. The confined quarters associated with space travel require researchers to focus on smaller plants that yield proportionately large amounts of biomass. This wheat crop takes about 85 days to grow before harvest.' Plant experiments such as this are the type of life sciences research that will be conducted at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  16. Numerical support of laboratory experiments: Attenuation and velocity estimations

    NASA Astrophysics Data System (ADS)

    Saenger, Erik; Madonna, Claudio; Frehner, Marcel; Almqvist, Bjarne

    2014-02-01

    We show that numerical support of laboratory experiments can significantly increase the understanding and simplify the interpretation of the obtained laboratory results. First we perform simulations of the Seismic Wave Attenuation Module to measure seismic attenuation of reservoir rocks. Our findings confirm the accuracy of this system. However, precision can be further improved by optimizing the sensor positions. Second, we model wave propagation for an ultrasonic pulse transmission experiment used to determine pressure- and temperature-dependent seismic velocities in the rock. Multiple waves are identified in our computer experiment, including bar waves. The metal jacket that houses the sample assembly needs to be taken into account for a proper estimation of the ultrasonic velocities. This influence is frequency-dependent.

  17. Dynamics of Protonated Peptide Ion Collisions with Organic Surfaces: Consonance of Simulation and Experiment

    SciTech Connect

    Pratihar, Subha; Barnes, George L.; Laskin, Julia; Hase, William L.

    2016-08-18

    In this Perspective mass spectrometry experiments and chemical dynamics simulations are described which have explored the atomistic dynamics of protonated peptide ions, peptide-H+, colliding with organic surfaces. These studies have investigated surface-induced dissociation (SID) for which peptide-H+ fragments upon collision with the surface, peptide-H+ physisorption on the surface, soft landing (SL), and peptide-H+ reaction with the surface, reactive landing (RL). The simulations include QM+MM and QM/MM direct dynamics. For collisions with self-assembled monolayer (SAM) surfaces there is quite good agreement between experiment and simulation in the efficiency of energy transfer to the peptide-H+ ion’s internal degrees of freedom. Both the experiments and simulations show two mechanisms for peptide-H+ fragmentation, i.e. shattering and statistical, RRKM dynamics. Mechanisms for SL are probed in simulations of collisions of protonated dialanine with a perfluorinated SAM surface. RL has been studied experimentally for a number of peptide-H+ + surface systems, and qualitative agreement between simulation and experiment is found for two similar systems.

  18. Definition of experiments and instruments for a communication/navigation research laboratory. Volume 2: Experiment selection

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The selection and definition of candidate experiments and the associated experiment instrumentation requirements are described. Information is presented that addresses the following study objectives: (1) determine specific research and technology needs in the comm/nav field through a survey of the scientific/technical community; (2) develop manned low earth orbit space screening criteria and compile lists of potential candidate experiments; (3) in Blue Book format, define and describe selected candidate experiments in sufficient detail to develop laboratory configuration designs and layouts; and (4) develop experiment time phasing criteria and recommend a payload for sortie can/early laboratory missions.

  19. Development, Evaluation and Use of a Student Experience Survey in Undergraduate Science Laboratories: The Advancing Science by Enhancing Learning in the Laboratory Student Laboratory Learning Experience Survey

    NASA Astrophysics Data System (ADS)

    Barrie, Simon C.; Bucat, Robert B.; Buntine, Mark A.; Burke da Silva, Karen; Crisp, Geoffrey T.; George, Adrian V.; Jamie, Ian M.; Kable, Scott H.; Lim, Kieran F.; Pyke, Simon M.; Read, Justin R.; Sharma, Manjula D.; Yeung, Alexandra

    2015-07-01

    Student experience surveys have become increasingly popular to probe various aspects of processes and outcomes in higher education, such as measuring student perceptions of the learning environment and identifying aspects that could be improved. This paper reports on a particular survey for evaluating individual experiments that has been developed over some 15 years as part of a large national Australian study pertaining to the area of undergraduate laboratories-Advancing Science by Enhancing Learning in the Laboratory. This paper reports on the development of the survey instrument and the evaluation of the survey using student responses to experiments from different institutions in Australia, New Zealand and the USA. A total of 3153 student responses have been analysed using factor analysis. Three factors, motivation, assessment and resources, have been identified as contributing to improved student attitudes to laboratory activities. A central focus of the survey is to provide feedback to practitioners to iteratively improve experiments. Implications for practitioners and researchers are also discussed.

  20. Wiki Laboratory Notebooks: Supporting Student Learning in Collaborative Inquiry-Based Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Lawrie, Gwendolyn Angela; Grøndahl, Lisbeth; Boman, Simon; Andrews, Trish

    2016-06-01

    Recent examples of high-impact teaching practices in the undergraduate chemistry laboratory that include course-based undergraduate research experiences and inquiry-based experiments require new approaches to assessing individual student learning outcomes. Instructors require tools and strategies that can provide them with insight into individual student contributions to collaborative group/teamwork throughout the processes of experimental design, data analysis, display and communication of their outcomes in relation to their research question(s). Traditional assessments in the form of laboratory notebooks or experimental reports provide limited insight into the processes of collaborative inquiry-based activities. A wiki environment offers a collaborative domain that can potentially support collaborative laboratory processes and scientific record keeping. In this study, the effectiveness of the wiki in supporting laboratory learning and assessment has been evaluated through analysis of the content and histories for three consenting, participating groups of students. The conversational framework has been applied to map the relationships between the instructor, tutor, students and laboratory activities. Analytics that have been applied to the wiki platform include: character counts, page views, edits, timelines and the extent and nature of the contribution by each student to the wiki. Student perceptions of both the role and the impact of the wiki on their experiences and processes have also been collected. Evidence has emerged from this study that the wiki environment has enhanced co-construction of understanding of both the experimental process and subsequent communication of outcomes and data. A number of features are identified to support success in the use of the wiki platform for laboratory notebooks.

  1. Scientific equity: experiments in laboratory education in Ghana.

    PubMed

    Osseo-Asare, Abena Dove

    2013-12-01

    During the 1960s the Ministry of Education in Ghana created a network of school laboratories to increase scientific literacy among young citizens. The ministry stocked these "Science Centres" with imported beakers, Bunsen burners, and books. Education officials and university scientists worked with teachers to create lesson plans on water, air, plants, and other topics. The government hoped that scientifically minded schoolchildren would be better prepared to staff the industries of the future. The adoption of laboratory norms represented a desire for scientific equity, rather than a condition of cultural mimicry. Interviews with ministry officials and science educators, alongside letters and reports, indicate how students and teachers appropriated the laboratories in the small West African nation. Their experiences in mobilizing resources from across Ghana and around the world provide a metaphor for ongoing efforts to establish access to scientific goods in Africa.

  2. The Effect of Guided-Inquiry Laboratory Experiments on Science Education Students' Chemistry Laboratory Attitudes, Anxiety and Achievement

    ERIC Educational Resources Information Center

    Ural, Evrim

    2016-01-01

    The study aims to search the effect of guided inquiry laboratory experiments on students' attitudes towards chemistry laboratory, chemistry laboratory anxiety and their academic achievement in the laboratory. The study has been carried out with 37 third-year, undergraduate science education students, as a part of their Science Education Laboratory…

  3. Spectral probing of impact-generated vapor in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Schultz, Peter H.; Eberhardy, Clara A.

    2015-03-01

    High-speed spectra of hypervelocity impacts at the NASA Ames Vertical Gun Range (AVGR) captured the rapidly evolving conditions of impact-generated vapor as a function of impact angle, viewpoint, and time (within the first 50 μs). Impact speeds possible at the AVGR (<7 km/s) are insufficient to induce significant vaporization in silicates, other than the high-temperature (but low-mass) jetting component created at first contact. Consequently, this study used powdered dolomite as a proxy for surveying the evolution and distribution of chemical constituents within much longer lasting vapor. Seven separate telescopes focused on different portions of the impact vapor plume and were connected through quartz fibers to two 0.35 cm monochromaters. Quarter-space experiments reduced the thermal background and opaque phases due to condensing particles and heated projectile fragments while different exposure times isolated components passing through different the fields of view, both above and below the surface within the growing transient cavity. At early times (<5 μs), atomic emission lines dominate the spectra. At later times, molecular emission lines dominate the composition of the vapor plume along a given direction. Layered targets and target mixtures isolated the source and reveal that much of the vaporization comes from the uppermost surface. Collisions by projectile fragments downrange also make significant contributions for impacts below 60° (from the horizontal). Further, impacts into mixtures of silicates with powdered dolomite reveal that frictional heating must play a role in vapor production. Such results have implications for processes controlling vaporization on planetary surfaces including volatile release, atmospheric evolution (formation and erosion), vapor generated by the Deep Impact collision, and the possible consequences of the Chicxulub impact.

  4. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Original photo and caption dated October 8, 1991: 'Plant researchers Lisa Ruffe and Neil Yorio prepare to harvest a crop of Waldann's Green Lettuce from KSC's Biomass Production Chamber (BPC). KSC researchers have grown several different crops in the BPC to determine which plants will better produce food, water and oxygen on long-duration space missions.' Their work is an example of the type of life sciences research that will be conducted at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  5. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Original photo and caption dated October 8, 1991: 'Plant researchers Neil Yorio and Lisa Ruffe prepare to harvest a crop of Waldann's Green Lettuce from KSC's Biomass Production Chamber (BPC). KSC researchers have grown several different crops in the BPC to determine which plants will better produce food, water and oxygen on long-duration space missions.' Their work is an example of the type of life sciences research that will be conducted at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  6. The Underground Laboratory in South Korea : facilities and experiments

    NASA Astrophysics Data System (ADS)

    Kim, Yeongduk

    2017-01-01

    We have developed underground physics programs for last 15 years in South Korea. The scientific and technical motivation for this initiative was the lack of local facility of a large accelerator in Korea. Thanks to the large underground electric power generator in Yangyang area, we could construct a deep underground laboratory (Yangyang Laboratory, Y2L) and has performed some pioneering experiments for dark matter search and double beta decay experiments. Since year of 2013, a new research center in the Institute for Basic Science (IBS), Center for Underground Physics (CUP), is approved by the government and Y2L laboratory is managed by CUP. Due to the limited space in Y2L, we are proposing to construct a new deep underground laboratory where we can host larger scale experiments of next generation. The site is in an active iron mine, and will be made in 1100 meter underground with a space of about 2000 m2 by the end of 2019. I will describe the status and future plan for this underground laboratory. CUP has two main experimental programs. (1) Identification of dark matter : The annual modulation signal of DAMA/LIBRA experiment has been contradictory to many other experiments such as XENON100, LUX, and Super CDMS. Yale University and CUP (COSINE-100) experimentalists agreed to do an experiment together at the Y2L and recently commissioned a 100kg scale low background NaI(Tl) crystal experiment. In future, we will develop NaI(Tl) crystals with lower internal backgrounds and try to run identical detectors at both north and south hemisphere. Low mass WIMP search is also planned with a development of low temperature sensors coupled with highly scintillating crystals. (2) Neutrinoless double beta decay search : The mass of the lightest neutrino and the Majorana nature of the neutrinos are not determined yet. Neutrinoless double beta decay experiment can answer both of the questions directly, and ultra-low backgrounds and excellent energy resolution are critical to

  7. Equipment qualification testing evaluation experiences at Sandia National Laboratories

    SciTech Connect

    Bustard, L.D.; Wyant, F.J.; Bonzon, L.L.; Gillen, K.T.

    1986-01-01

    The USNRC has sponsored a number of programs at Sandia National Laboratories specifically addressing safety-related equipment qualification. The most visible of these programs has been the Qualification Testing Evaluation (QTE) program. Other relevant programs have included the Equipment Qualification Methodology Research Test program (CAP). Over a ten year period these programs have collectively tested numerous types of safety-related equipment. Some insights and conclusions extracted from these testing experiences are summarized in this report.

  8. Visualizing electromagnetic fields in laser-produced counterstreaming plasma experiments for collisionless shock laboratory astrophysics

    NASA Astrophysics Data System (ADS)

    Kugland, Nathan

    2012-10-01

    In astrophysical settings, large and stable structures often emerge from turbulent supersonic plasma flows. Examples include the cosmic magnetic field and the collisionless shocks [1] in supernova remnants. In a scaled environment created with the high power lasers at OMEGA EP, proton imaging shows that large, stable electromagnetic field structures arise within counterstreaming supersonic plasmas [2]. These field structures are large compared to the fundamental turbulence scale lengths of the plasma (e.g. the Debye length and the ion skin-depth), indicating a high degree of self-organization. These features remain in place from 4 to 7 ns, indicating a high degree of stability. At early times out to at least 8 ns, intra-jet ion collisions are strong (due to relatively low thermal velocities) but inter-jet ion collisions are rare (due to relatively high flow velocities), permitting the evolution of both hydrodynamic and collisionless plasma instabilities [3, 4]. This paper will present detailed results from our laboratory astrophysics experiments. Prepared by LLNL for US DOE under Contract DE-AC52-07NA27344.[4pt] [1] H. S. Park et al, HEDP, 8, 38 (2011).[0pt] [2] N.L. Kugland et al, submitted to Nature Physics (2012).[0pt] [3] J.S. Ross et al, Phys. Plas., 19, 056501 (2012).[0pt] [3] D.D. Ryutov et al, Phys. Plas., 19, 076532 (2012).

  9. Laboratory astrophysics experiments relating to ionising and weakly radiative shocks

    NASA Astrophysics Data System (ADS)

    Cross, Joseph; Foster, John; Graham, Peter; Busschaert, Clotilde; Charpentier, Nicolas; Danson, Colin; Doyle, Hugo; Drake, R. Paul; Falize, Emeric; Fyrth, Jim; Gumbrell, Edward; Koenig, Michel; Kuranz, Carolyn; Loupias, Berenice; Michaut, Claire; Patankar, Sid; Skidmore, Jonathan; Spindloe, Christopher; Tubman, Ellie; Woolsey, Nigel; Yurchak, Roman; Gregori, Gianluca

    2014-10-01

    The aim of the POLAR project is to simulate, in the laboratory, the accretion shock region of a magnetic cataclysmic variable binary star system. Scaling laws have shown that laser experiments can be related to astrophysical phenomena by matching relevant dimensionless parameters. As well as forming a reverse shock, relevant to the POLAR project, the experimental system is also likely formed of a weakly radiating shock and an ionisation front. Results from our experiment at the Orion Laser are presented here, alongside comparisons to simulation and the astrophysical case (of relevance to triggered star formation).

  10. Women's experiences in the engineering laboratory in Japan

    NASA Astrophysics Data System (ADS)

    Hosaka, Masako

    2014-07-01

    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 relationship between men and women is used as a framework. Findings suggest that women generally had a discouraging experience while working with their male peers. Specifically, women participated less and lost confidence by comparing with the men who appeared to be confident and competent.

  11. Differentiating biochemistry course laboratories based on student experience.

    PubMed

    Jakubowski, Henry V

    2011-01-01

    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 no experience with biochemical techniques and biology and biochemistry majors who do. This manuscript describes a strategy for differentiating biochemistry labs to meet the needs of students with differing backgrounds.

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

    SciTech Connect

    Johnson, B.

    1992-12-31

    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.

  13. Holographic study of a vibrating bell: An undergraduate laboratory experiment

    NASA Astrophysics Data System (ADS)

    Menou, Kristen; Audit, Benjamin; Boutillon, Xavier; Vach, Holger

    1998-05-01

    An experiment combining holography and musical acoustics is described. Structures of vibration modes of a bell are visualized by time-average holography under either acoustical or mechanical excitation. The vibration amplitude as measured by an accelerometer shows very good quantitative agreement with that determined from our holograms by fringe counting. An effect of degenerate level separation is shown in the mechanical case. It is argued that this experiment is not only very inexpensive for a physics laboratory already equipped for holography, but that it also strongly stimulates students to deepen their insight into a variety of different topics in applied physics.

  14. An in silico DNA cloning experiment for the biochemistry laboratory.

    PubMed

    Elkins, Kelly M

    2011-01-01

    This laboratory exercise introduces students to concepts in recombinant DNA technology while accommodating a major semester project in protein purification, structure, and function in a biochemistry laboratory for junior- and senior-level undergraduate students. It is also suitable for forensic science courses focused in DNA biology and advanced high school biology classes. Students begin by examining a plasmid map with the goal of identifying which restriction enzymes may be used to clone a piece of foreign DNA containing a gene of interest into the vector. From the National Center for Biotechnology Initiative website, students are instructed to retrieve a protein sequence and use Expasy's Reverse Translate program to reverse translate the protein to cDNA. Students then use Integrated DNA Technologies' OligoAnalyzer to predict the complementary DNA strand and obtain DNA recognition sequences for the desired restriction enzymes from New England Biolabs' website. Students add the appropriate DNA restriction sequences to the double-stranded foreign DNA for cloning into the plasmid and infecting Escherichia coli cells. Students are introduced to computational biology tools, molecular biology terminology and the process of DNA cloning in this valuable single session, in silico experiment. This project develops students' understanding of the cloning process as a whole and contrasts with other laboratory and internship experiences in which the students may be involved in only a piece of the cloning process/techniques. Students interested in pursuing postgraduate study and research or employment in an academic biochemistry or molecular biology laboratory or industry will benefit most from this experience.

  15. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Original photo and caption dated August 14, 1995: 'KSC plant physiologist Dr. Gary Stutte (right) and Cheryl Mackowiak harvest potatoes grown in the Biomass Production Chamber of the Controlled Enviornment Life Support System (CELSS in Hangar L at Cape Canaveral Air Station. During a 418-day 'human rated' experiment, potato crops grown in the chamber provided the equivalent of a continuous supply of the oxygen for one astronaut, along with 55 percent of that long-duration space flight crew member's caloric food requirements and enough purified water for four astronauts while absorbing their expelled carbon dioxide. The experiment provided data that will help demonstarte the feasibility of the CELSS operating as a bioregenerative life support system for lunar and deep-space missions that can operate independently without the need to carry consumables such as air, water and food, while not requiring the expendable air and water system filters necessary on today's human-piloted spacecraft.' Their work is an example of the type of life sciences research that will be conducted at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  16. Research and the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Original photo and caption dated August 14, 1995: 'KSC plant physiologist Dr. Gary Stutte harvests a potato grown in the Biomass Production Chamber of the Controlled environment Life Support system (CELSS) in Hangar L at Cape Canaveral Air Station. During a 418-day 'human rated' experiment, potato crops grown in the chamber provided the equivalent of a continuous supply of the oxygen for one astronaut, along with 55 percent of that long-duration space flight crew member's caloric food requirements and enough purified water for four astronauts while absorbing their expelled carbon dioxide. The experiment provided data that will help demonstarte the feasibility of the CELSS operating as a bioregenerative life support system for lunar and deep-space missions that can operate independently without the need to carry consumables such as air, water and food, while not requiring the expendable air and water system filters necessary on today's human-piloted spacecraft.' His work is an example of the type of life sciences research that will be conducted at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  17. Design of laboratory experiments to study radiation-driven implosions

    NASA Astrophysics Data System (ADS)

    Keiter, P. A.; Trantham, M.; Malamud, G.; Klein, S. R.; Davis, J.; VanDervort, R.; Shvarts, D.; Drake, R. P.; Stone, J. M.; Fraenkel, M.; Frank, Y.; Raicher, E.

    2017-03-01

    The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud's fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport is much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. We present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. We have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.

  18. Inter-Laboratory Uranium Double-Spike Experiment

    SciTech Connect

    Russ, G. P

    1999-11-11

    In environmental samples, the major analytical limitation on the use of uranium {sup 238}U/{sup 235}U determinations as an indicator of uranium enrichment is mass dependent bias occurring during the measurement. The double-spike technique can be used to correct the data for this effect. The purpose of this experiment was to evaluate the variation of mass bias among several laboratories and to determine the extent to which the double-spike could be used to reduce analytical uncertainty. Four laboratories performed replicate analyses on each of three samples. Generally mass bias was determined to be small compared to the random scatter of the measurements, but in at least one case, the bias was > 1%. In 8 of 12 cases, intra-laboratory variance was reduced when the double-spike correction was applied. For all three samples, the inter-laboratory variance was decreased, though the decrease was small. Based on a reasonable assumption about the true isotopic compositions of the samples, the accuracy of 11 of the twelve analyses was improved by applying the double spike correction. When the double spike is used to correct for mass bias, the {sup 238}U/{sup 235}U accuracy is better than 1% even for samples as small as 1 ng. For 50 ng of uranium, 0.1% accuracy was achieved.

  19. Cryogenic Fracturing: Laboratory Visualization Experiments and Numerical Simulations Using Peridynamics

    NASA Astrophysics Data System (ADS)

    Martin-Short, R.; Edmiston, J. K.

    2015-12-01

    Typical hydraulic fracturing operations involve the use of a large quantity of water, which can be problematic for several reasons including possible formation (permeability) damage, disposal of waste water, and the use of precious local water resource. An alternate reservoir permeability enhancing technology not requiring water is cryogenic fracturing. This method induces controlled fracturing of rock formations by thermal shock and has potentially important applications in the geothermal and hydrocarbon industries. In this process, cryogenic fluid—such as liquid nitrogen—is injected into the subsurface, causing fracturing due to thermal gradients. These fractures may improve the formation permeability relative to that achievable by hydraulic fracturing alone. We conducted combined laboratory visualization and numerical simulations studies of thermal-shock-induced fracture initiation and propagation resulting from liquid nitrogen injection in rock and analog materials. The experiment used transparent soda-lime glass cubes to facilitate real-time visualization of fracture growth and the fracture network geometry. In this contribution, we report the effect of overall temperature difference between cryogenic fluid and solid material on the produced fracture network, by pre-heating the glass cubes to several temperatures and injecting liquid nitrogen. Temperatures are monitored at several points by thermocouple and the fracture evolution is captured visually by camera. The experiment was modeled using a customized, thermoelastic, fracture-capable numerical simulation code based on peridynamics. The performance of the numerical code was validated by the results of the laboratory experiments, and then the code was used to study the different factors affecting a cryogenic fracturing operation, including the evolution of residual stresses and constitutive relationships for material failure. In complex rock such as shale, understanding the process of cryogenic

  20. Georgia Teachers in Academic Laboratories: Research Experiences in the Geosciences

    NASA Astrophysics Data System (ADS)

    Barrett, D.

    2005-12-01

    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

  1. Laboratory Experiments of High Mach Number Raditaive Jets

    NASA Astrophysics Data System (ADS)

    Frank, A.; Gardiner, T.; Blackman, E.; Lebedev, S.; Chittenden, J.; Beg, S.; Bland, S.; Ciardi, A.; Ampleford, D.; Hughes, S.; Haines, M. G.

    2001-05-01

    We present astrophysically relevent experiments on the generation of a highly supersonic plasma jet by a convergent plasma flow. The flow is produced by electrodynamic acceleration of plasma in a conical array of fine metallic wires (a modification of the wire array Z-pinch). Stagnation of the plasma flow on the axis of symmetry forms a standing conical shock, which effectively collimates the flow in the axial direction. This scenario is essentially similar to that discussed by Cantó et al 1988 as a possible, purely hydrodynamic mechanism of jet formation in young stellar objects. Experiments using different materials (Al, Fe and W) show that a highly supersonic (M 20) and a well-collimated jet is generated when the radiative cooling rate of the plasma is significant. The interaction of this jet with a plasma target could be used for scaled laboratory astrophysical experiments on hydrodynamic instabilities in decelerated plasma flow.

  2. Simulations of Laboratory Astrophysics Experiments using the CRASH code

    NASA Astrophysics Data System (ADS)

    Trantham, Matthew; Kuranz, Carolyn; Fein, Jeff; Wan, Willow; Young, Rachel; Keiter, Paul; Drake, R. Paul

    2015-11-01

    Computer simulations can assist in the design and analysis of laboratory astrophysics experiments. The Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan developed a code that has been used to design and analyze high-energy-density experiments on OMEGA, NIF, and other large laser facilities. This Eulerian code uses block-adaptive mesh refinement (AMR) with implicit multigroup radiation transport, electron heat conduction and laser ray tracing. This poster will demonstrate some of the experiments the CRASH code has helped design or analyze including: Kelvin-Helmholtz, Rayleigh-Taylor, magnetized flows, jets, and laser-produced plasmas. This work is funded by the following grants: DEFC52-08NA28616, DE-NA0001840, and DE-NA0002032.

  3. The Heavy Photon Search experiment at Jefferson Laboratory

    SciTech Connect

    Celentano, Andrea

    2014-11-01

    The Heavy Photon Search experiment (HPS) at Jefferson Laboratory will search for a new U(1) massive gauge boson, or "heavy-photon", mediator of a new fundamental interaction, called "dark-force", that couples to ordinary photons through kinetic mixing. HPS has sensitivity in the mass range 20 MeV – 1 GeV and coupling epsilon2 between 10-5 and 10-10. The HPS experiment will look for the e+e- decay of the heavy photon, by resonance search and detached vertexing, in an electron beam fixed target experiment. HPS will use a compact forward spectrometer, which employs silicon microstrip detectors for vertexing and tracking, and a PbWO4 electromagnetic calorimeter for energy measurement and fast triggering.

  4. Constraining PCP Violating Varying Alpha Theory through Laboratory Experiments

    SciTech Connect

    Maity, Debaprasad; Chen, Pisin; /NCTS, Taipei /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC

    2012-06-06

    In this report we have studied the implication of a parity and charge-parity (PCP) violating interaction in varying alpha theory. Due to this interaction, the state of photon polarization can change when it passes through a strong background magnetic field. We have calculated the optical rotation and ellipticity of the plane of polarization of an electromagnetic wave and tested our results against different laboratory experiments. Our model contains a PCP violating parameter {beta} and a scale of alpha variation {omega}. By analyzing the laboratory experimental data, we found the most stringent constraints on our model parameters to be 1 {le} {omega} {le} 10{sup 13} GeV{sup 2} and -0.5 {le} {beta} {le} 0.5. We also found that with the existing experimental input parameters it is very difficult to detect the ellipticity in the near future.

  5. The spacecraft control laboratory experiment optical attitude measurement system

    NASA Technical Reports Server (NTRS)

    Welch, Sharon S.; Montgomery, Raymond C.; Barsky, Michael F.

    1991-01-01

    A stereo camera tracking system was developed to provide a near real-time measure of the position and attitude of the Spacecraft COntrol Laboratory Experiment (SCOLE). The SCOLE is a mockup of the shuttle-like vehicle with an attached flexible mast and (simulated) antenna, and was designed to provide a laboratory environment for the verification and testing of control laws for large flexible spacecraft. Actuators and sensors located on the shuttle and antenna sense the states of the spacecraft and allow the position and attitude to be controlled. The stereo camera tracking system which was developed consists of two position sensitive detector cameras which sense the locations of small infrared LEDs attached to the surface of the shuttle. Information on shuttle position and attitude is provided in six degrees-of-freedom. The design of this optical system, calibration, and tracking algorithm are described. The performance of the system is evaluated for yaw only.

  6. Elucidating GPR Response to Biological Activity: Field and Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Tsoflias, G. P.; Schillig, P. C.; McGlashan, M. A.; Roberts, J. A.; Devlin, J. F.

    2010-12-01

    Recent studies of the geophysical signatures of biological processes in earth environments have resulted in the emergent field of “biogeophysics”. The ability to monitor remotely and to quantify active biological processes in the subsurface can have transformative implications to a wide range of investigations, including the bioremediation of contaminated sites. Previous studies have demonstrated that ground-penetrating radar (GPR) can be used to detect the products of microbial activity in the subsurface, such as changes in bulk electrical conductivity, mineral dissolution and precipitation, and the formation of biogenic gas. We present field and laboratory experiments that offer insights to the response of GPR signals to microbial activity. In the field, time-lapse borehole radar tomography was used to monitor biodegradation of a hydrocarbon plume over a period of two years. A dense grid of fourteen borehole pairs monitoring the bioactive region showed radar wave velocity changes of +/-4% and signal attenuation changes of +/-25%. These GPR observations correlated spatially and temporally to independent measurements of groundwater velocity and geochemical variations that occurred in response to microbial activity. The greatest relative changes in radar wave velocity of propagation and attenuation were observed in the region of enhanced bacterial stimulation where biomass growth was the greatest. Radar wave velocity and attenuation decreased during periods of enhanced biostimulation. Two laboratory experiments were conducted to further assess radar response to biomass growth. The first experiment monitored GPR wave transmission through a water-saturated quartz-sand reactor during the course of enhanced biostimulation. Radar wave velocity initially decreased as a result of bacterial activity and subsequently increased rapidly as biogenic gas formed in the pore space. Radar signal attenuation increased during the course of the experiment as a result of an

  7. Exploration of the Kinked Jet in the Crab Nebula with Scaled Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Li, Chikang

    2015-11-01

    X-ray images from the Chandra X-ray Observatory show that the South-East jet in the Crab nebula changes direction every few years. This remarkable phenomenon is also frequently observed for jets in other pulsar-wind nebulae and in other astrophysical objects. Numerical simulations suggest that it may be a consequence of current-driven, magnetohydrodynamic (MHD) instabilities taking place in the jet, yet that is just a hypothesis without verification in controlled experiments. To that end, we recently conducted scaled laboratory experiments that reproduced this phenomenon. In these experiments, a supersonic plasma jet was generated in the collision of two laser-produced plasma plumes, and this jet was radiographed from the side using 15-MeV and 3-MeV protons. It was observed that if self-generated toroidal magnetic fields around the jet were strong enough, they triggered plasma instabilities that caused substantial deflections throughout the jet propagation, mimicking the kinked jet structure seen in the Crab Nebula. We have modeled these laboratory experiments with comprehensive two- and three-dimensional numerical simulations, which in conjunction with the experiments provide compelling evidence that we have an accurate model of the most important physics of magnetic fields and MHD instabilities in the observed jet in the Crab Nebula. The work described here was performed in part at the LLE National Laser User's Facility (NLUF), and was supported in part by US DOE (Grant No. DE-FG03- 03SF22691), LLNL (subcontract Grant No. B504974) and LLE (subcontract Grant No. 412160-001G).

  8. Perceived traffic risk for cyclists: the impact of near miss and collision experiences.

    PubMed

    Sanders, Rebecca L

    2015-02-01

    Though the percentage of people bicycling for transportation rose during the last decade, with an average increase in bicycle commuting of 47% (Flusche, 2012), still only 1% of all U.S. trips are made by bike (Flusche, 2010). Research suggests that people's concern regarding the risk of bicycling near traffic-namely the risk of being hit by a car-remain a significant barrier to widespread cycling. However, research has not disaggregated traffic risk to expose its many aspects and how they may affect bicyclists with differing skill levels, experiences, and behaviors. This study begins to address this gap in our understanding. Elaborating on results from an internet survey, this study examined various aspects of traffic risk among 406 potential and current bicyclists in the San Francisco Bay Area. The data indicate that perceived traffic risk negatively influences the decision to bicycle for potential and occasional bicyclists, although the influence decreases with cycling frequency. Additionally, cycling frequency seems to heighten awareness of traffic risk, particularly for cyclists who have experienced "near misses" or collisions. In particular, near misses were found to be (a) much more common than collisions and (b) more strongly associated than collisions with perceived traffic risk. The findings suggest that efforts targeting road user behaviors and roadway designs associated with these near misses could mitigate perceived and actual traffic risk for bicyclists, and thereby eventually help achieve higher cycling ridership.

  9. Experiments at The Virtual National Laboratory for Heavy Ion Fusion

    SciTech Connect

    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

    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.

  10. Simulation studies of plasma lens experiments at Daresbury laboratory

    NASA Astrophysics Data System (ADS)

    Hanahoe, K.; Mete, O.; Xia, G.; Angal-Kalinin, D.; Jones, J.; Smith, J.

    2016-03-01

    Experiments are planned to study plasma lensing using the VELA and CLARA Front End accelerators at Daresbury Laboratory. This paper presents results of 2-dimensional particle-in-cell simulations of the proposed experiments. The variation in focusing strength and emittance growth with beam and plasma parameters are studied in the overdense (plasma density much greater than bunch density) regime for the VELA beam. The effect of spherical and longitudinal aberrations on the beam emittance was estimated through numerical and theoretical studies. Simulation results show that a focusing strength equivalent to a magnetic field gradient of 10 T m-1 can be achieved using VELA, and a gradient of 247 T m-1 can be achieved using CLARA Front End.

  11. Macromolecular crystal growth experiments on International Microgravity Laboratory--1.

    PubMed Central

    Day, J.; McPherson, A.

    1992-01-01

    Macromolecular crystal growth experiments, using satellite tobacco mosaic virus (STMV) and canavalin from jack beans as samples, were conducted on a US Space Shuttle mission designated International Microgravity Laboratory--1 (IML-1), flown January 22-29, 1992. Parallel experiments using identical samples were carried out in both a vapor diffusion-based device (PCG) and a liquid-liquid diffusion-based instrument (CRYOSTAT). The experiments in each device were run at 20-22 degrees C and at colder temperatures. Crystals were grown in virtually every trial, but the characteristics of the crystals were highly dependent on the crystallization technique employed and the temperature experience of the sample. In general, very good results, based on visual inspection of the crystals, were obtained in both PCG and CRYOSTAT. Unusually impressive results were, however, achieved for STMV in the CRYOSTAT instrument. STMV crystals grown in microgravity by liquid-liquid diffusion were more than 10-fold greater in total volume than any STMV crystals previously grown in the laboratory. X-ray diffraction data collected from eight STMV crystals grown in CRYOSTAT demonstrated a substantial improvement in diffraction quality over the entire resolution range when compared to data from crystals grown on Earth. In addition, the extent of the diffraction pattern for the STMV crystals grown in space extended to 1.8 A resolution, whereas the best crystals that were ever grown under conditions of Earth's gravity produced data limited to 2.3 A resolution. Other observations indicate that the growth of macromolecular crystals is indeed influenced by the presence or absence of gravity. These observations further suggest, consistent with earlier results, that the elimination of gravity provides a more favorable environment for such processes. PMID:1303744

  12. E917 experiment: Probing the dynamics of HI collisions + searching for the QGP

    SciTech Connect

    Ogilvie, C.A.; E917 Collaboration

    1996-12-31

    Experiment E917 has two main goals: to understand and probe the detailed mechanism of hadronic rescattering in HI collisions and to systematically search for a small volume of QGP. Correlated, discrete changes in sensitive QGP signatures as a function of both centrality and beam energy could indicate the presence of new physics. A precursor to the QGP is the possible change of hadronic properties in a dense medium. We will measure the {phi} and K{sup *} effective mass as a function of centrality to search for any change in the width or mass of these particles.

  13. Salt dissolution and sinkhole formation: Results of laboratory experiments

    NASA Astrophysics Data System (ADS)

    Oz, Imri; Eyal, Shalev; Yoseph, Yechieli; Ittai, Gavrieli; Elad, Levanon; Haim, Gvirtzman

    2016-10-01

    The accepted mechanism for the formation of thousands of sinkholes along the coast of the Dead Sea suggests that their primary cause is dissolution of a salt layer by groundwater undersaturated with respect to halite. This is related to the drop in the Dead Sea level, which caused a corresponding drop of the freshwater-saltwater interface, resulting in fresher groundwater replacing the brines that were in contact with the salt layer. In this study we used physical laboratory experiments to examine the validity of this mechanism by reproducing the full dynamic natural process and to examine the impact of different hydrogeological characteristics on this process. The experimental results show surface subsidence and sinkhole formation. The stratigraphic configurations of the aquifer, together with the mechanical properties of the salt layer, determine the dynamic patterns of the sinkhole formation (instantaneous versus gradual formation). Laboratory experiments were also used to study the potential impact of future stratification in the Dead Sea, if and when the "Red Sea-Dead Sea Canal" project is carried out, and the Dead Sea level remains stable. The results show that the dissolution rates are slower by 1 order of magnitude in comparison with a nonstratified saltwater body, and therefore, the processes of salt dissolution and sinkhole formation will be relatively restrained under these conditions.

  14. Laboratory plasma physics experiments using merging supersonic plasma jets

    SciTech Connect

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

    2015-04-01

    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 railguns. 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: ne ≈ ni ~ 10¹⁶ cm⁻³, Te ≈ Ti ≈ 1.4 eV, Vjet ≈ 30–100 km/s, mean charge $\\bar{Z}$ ≈ 1, sonic Mach number Ms ≡ Vjet/Cs > 10, jet diameter = 5 cm, and jet length ≈ 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.

  15. Laboratory plasma physics experiments using merging supersonic plasma jets

    DOE PAGES

    Hsu, S. C.; Moser, A. L.; Merritt, E. C.; ...

    2015-04-01

    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 railguns. 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: ne ≈ ni ~ 10¹⁶ cm⁻³, Te ≈ Ti ≈ 1.4 eV, Vjet ≈ 30–100 km/s, mean chargemore » $$\\bar{Z}$$ ≈ 1, sonic Mach number Ms ≡ Vjet/Cs > 10, jet diameter = 5 cm, and jet length ≈ 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.« less

  16. Computational Modeling of Laboratory X-ray Emission due to Low-Energy Collisions of H-like and He-like ions with H2

    NASA Astrophysics Data System (ADS)

    Miller, Ansley; Mullen, Patrick Dean; Cumbee, Renata; Stancil, Phillip C.; Leutenegger, Maurice A.

    2016-06-01

    Charge exchange between highly-charged ions and neutral molecules occurs when the solar wind, or other astrophysical plasmas, collide with cool gas. This process emits observable X-rays with specific line intensities. Recent CX experiments at Lawrence Livermore National Laboratory measured the X-ray hardness ratios of low-energy collisions between hydrogen- and helium-like ions with H2 (Leutenegger et al. 2010). Using our recently developed X-ray modeling package, Kronos_v2 (Mullen et al. 2016), which utilizes multi-channel Landau-Zener charge exchange cross sections, we have computed theoretical hydrogen-like hardness ratios to aid in interpretation of the experimental data. While the computed hardness ratios are somewhat smaller than the experiment, it shows better agreement than earlier classical trajectory predictions. We are also in the process of building Kronos_v3; further enhancing the comprehensive charge exchange database to include helium-like and multielectron ions to allow for comparison with experiments and for models of hot astrophysical environments such as supernova remnants, star-forming galaxies, and galaxy clusters.Leutenegger, M. et al. 2010, Phys. Rev. Lett., 105, 063201Mullen, P. D. et al., 2016, ApJS, in press

  17. Kinetics of Papain: An Introductory Biochemistry Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Cornely, Kathleen; Crespo, Eric; Earley, Michael; Kloter, Rachel; Levesque, Aime; Pickering, Mary

    1999-05-01

    Enzyme kinetics experiments are popular in the undergraduate laboratory. These experiments have pedagogic value because they reinforce the concepts of Michaelis-Menten kinetics covered in the lecture portion of the course and give students the experience of calculating kinetic constants from data they themselves have generated. In this experiment, we investigate the kinetics of the thiol protease papain. The source of the papain is commercially available papaya latex. A specific substrate, Na-benzoyl-arginine-p-nitroanilide (BAPNA), is used, which takes advantage of the fact that papain interacts with a phenylalanine residue two amino acids away from the peptide bond cleaved. Upon hydrolysis by papain, a bright yellow product is released, p-nitroaniline. This allows the reaction to be monitored spectrophotometrically by measuring the rate of formation of the p-nitroaniline product as a function of the increase in absorbance of the solution at the lmax of p-nitroaniline (400 nm) over time at various substrate concentrations. These data are used to plot a Lineweaver-Burk plot from which the vmax and KM are obtained. If time permits, students carry out additional investigations in which e of p-nitroaniline is measured, the enzyme solution protein concentration is measured, the enzyme purity is evaluated by SDS-PAGE, and a pH-rate profile is constructed from experimental data.

  18. Laboratory Experiments and Instrument Intercomparison Studies of Carbonaceous Aerosol Particles

    SciTech Connect

    Davidovits, Paul

    2015-10-20

    Aerosols containing black carbon (and some specific types of organic particulate matter) directly absorb incoming light, heating the atmosphere. In addition, all aerosol particles backscatter solar light, leading to a net-cooling effect. Indirect effects involve hydrophilic aerosols, which serve as cloud condensation nuclei (CCN) that affect cloud cover and cloud stability, impacting both atmospheric radiation balance and precipitation patterns. At night, all clouds produce local warming, but overall clouds exert a net-cooling effect on the Earth. The effect of aerosol radiative forcing on climate may be as large as that of the greenhouse gases, but predominantly opposite in sign and much more uncertain. The uncertainties in the representation of aerosol interactions in climate models makes it problematic to use model projections to guide energy policy. The objective of our program is to reduce the uncertainties in the aerosol radiative forcing in the two areas highlighted in the ASR Science and Program Plan. That is, (1) addressing the direct effect by correlating particle chemistry and morphology with particle optical properties (i.e. absorption, scattering, extinction), and (2) addressing the indirect effect by correlating particle hygroscopicity and CCN activity with particle size, chemistry, and morphology. In this connection we are systematically studying particle formation, oxidation, and the effects of particle coating. The work is specifically focused on carbonaceous particles where the uncertainties in the climate relevant properties are the highest. The ongoing work consists of laboratory experiments and related instrument inter-comparison studies both coordinated with field and modeling studies, with the aim of providing reliable data to represent aerosol processes in climate models. The work is performed in the aerosol laboratory at Boston College. At the center of our laboratory setup are two main sources for the production of aerosol particles: (a

  19. Lab-scale ash production by abrasion and collision experiments of porous volcanic samples

    NASA Astrophysics Data System (ADS)

    Mueller, S. B.; Lane, S. J.; Kueppers, U.

    2015-09-01

    In the course of explosive eruptions, magma is fragmented into smaller pieces by a plethora of processes before and during deposition. Volcanic ash, fragments smaller than 2 mm, has near-volcano effects (e.g. increasing mobility of PDCs, threat to human infrastructure) but may also cause various problems over long duration and/or far away from the source (human health and aviation matters). We quantify the efficiency of ash generation during experimental fracturing of pumiceous and scoriaceous samples subjected to shear and normal stress fields. Experiments were designed to produce ash by overcoming the yield strength of samples from Tenerife (Canary Islands, Spain), Sicily and Lipari Islands (Italy), with this study having particular interest in the < 355 μm fraction. Fracturing within volcanic conduits, plumes and pyroclastic density currents (PDCs) was simulated through a series of abrasion (shear) and collision (normal) experiments. An understanding of these processes is crucial as they are capable of producing very fine ash (< 10 μm). These particles can remain in the atmosphere for several days and may travel large distances (~ 1000s of km). This poses a threat to the aviation industry and human health. From the experiments we establish that abrasion produced the finest-grained material and up to 50% of the generated ash was smaller than 10 μm. In comparison, the collision experiments that applied mainly normal stress fields produced coarser grain sizes. Results were compared to established grain size distributions for natural fall and PDC deposits and good correlation was found. Energies involved in collision and abrasion experiments were calculated and showed an exponential correlation with ash production rate. Projecting these experimental results into the volcanic environment, the greatest amounts of ash are produced in the most energetic and turbulent regions of volcanic flows, which are proximal to the vent. Finest grain sizes are produced in PDCs

  20. Discrepancies Between Laboratory Shock Experiments on Minerals and Natural Events

    NASA Astrophysics Data System (ADS)

    de Carli, P. S.; Xie, Z.; Sharp, T. G.

    2009-12-01

    Numerous laboratory shock recovery experiments performed over the past 50 years have provided substantial data on the effects of shock waves on rocks and minerals. However, it has become increasingly clear that the pressure "calibrations" based on shock effects observed in these experiments are inconsistent with interpretations based on static high-pressure data. A fundamental question is whether shock pressures are somehow different from static high pressures. Fifty years ago, many journal reviewers doubted that phase transformations could take place on a sub-microsecond time scale. Shock wave workers responded by invoking "special" properties of shock compression. However, all available evidence is consistent with the hypothesis that phase transitions under shock pressure are no different from phase transitions under static high pressures. The discrepancies noted above result from the fact that the parameter space, especially shock pressure duration, accessible to shock recovery experiments is so small by comparison with natural events. Furthermore virtually all shock recovery experiments on rocks and minerals have used high impedance sample containers, with the result that the samples have been subjected to thermodynamic loading paths substantially from a natural event. Consider the case of a chondritic meteorite made up of minerals having a wide range of shock properties. In a natural shock event the transient (nano-second scale) shock pressure at the shock front can vary by as much as an order of magnitude from grain to grain or even within a single grain. There are corresponding local differences in shock temperature. Assuming a mineral grain size of about a mm, the pressure inhomogeneities will equilibrate in less than a microsecond, wheras the temperature inhomogenities will require seconds to equilibrate. Recent studies of high-pressure phases in meteorites have provided evidence for pressure durations in the range of seconds, long enough for high pressure

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

    NASA Technical Reports Server (NTRS)

    1972-01-01

    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.

  2. Scaled Laboratory Collisionless Shock Experiments in the Large Plasma Device

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    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.

  3. The Software Engineering Laboratory: An operational software experience factory

    NASA Technical Reports Server (NTRS)

    Basili, Victor R.; Caldiera, Gianluigi; Mcgarry, Frank; Pajerski, Rose; Page, Gerald; Waligora, Sharon

    1992-01-01

    For 15 years, the Software Engineering Laboratory (SEL) has been carrying out studies and experiments for the purpose of understanding, assessing, and improving software and software processes within a production software development environment at NASA/GSFC. The SEL comprises three major organizations: (1) NASA/GSFC, Flight Dynamics Division; (2) University of Maryland, Department of Computer Science; and (3) Computer Sciences Corporation, Flight Dynamics Technology Group. These organizations have jointly carried out several hundred software studies, producing hundreds of reports, papers, and documents, all of which describe some aspect of the software engineering technology that was analyzed in the flight dynamics environment at NASA. The studies range from small, controlled experiments (such as analyzing the effectiveness of code reading versus that of functional testing) to large, multiple project studies (such as assessing the impacts of Ada on a production environment). The organization's driving goal is to improve the software process continually, so that sustained improvement may be observed in the resulting products. This paper discusses the SEL as a functioning example of an operational software experience factory and summarizes the characteristics of and major lessons learned from 15 years of SEL operations.

  4. Internal Gravity Waves: Generation and Breaking Mechanisms by Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    la Forgia, Giovanni; Adduce, Claudia; Falcini, Federico

    2016-04-01

    Internal gravity waves (IGWs), occurring within estuaries and the coastal oceans, are manifest as large amplitude undulations of the pycnocline. IGWs propagating horizontally in a two layer stratified fluid are studied. The breaking of an IGW of depression shoaling upon a uniformly sloping boundary is investigated experimentally. Breaking dynamics beneath the shoaling waves causes both mixing and wave-induced near-bottom vortices suspending and redistributing the bed material. Laboratory experiments are conducted in a Perspex tank through the standard lock-release method, following the technique described in Sutherland et al. (2013). Each experiment is analysed and the instantaneous pycnocline position is measured, in order to obtain both geometric and kinematic features of the IGW: amplitude, wavelength and celerity. IGWs main features depend on the geometrical parameters that define the initial experimental setting: the density difference between the layers, the total depth, the layers depth ratio, the aspect ratio, and the displacement between the pycnoclines. Relations between IGWs geometric and kinematic features and the initial setting parameters are analysed. The approach of the IGWs toward a uniform slope is investigated in the present experiments. Depending on wave and slope characteristics, different breaking and mixing processes are observed. Sediments are sprinkled on the slope to visualize boundary layer separation in order to analyze the suspension e redistribution mechanisms due to the wave breaking.

  5. Laboratory astrophysical collisionless shock experiments on Omega and NIF

    NASA Astrophysics Data System (ADS)

    Park, Hye-Sook; Ross, J. S.; Huntington, C. M.; Fiuza, F.; Ryutov, D.; Casey, D.; Drake, R. P.; Fiksel, G.; Froula, D.; Gregori, G.; Kugland, N. L.; Kuranz, C.; Levy, M. C.; Li, C. K.; Meinecke, J.; Morita, T.; Petrasso, R.; Plechaty, C.; Remington, B.; Sakawa, Y.; Spitkovsky, A.; Takabe, H.; Zylstra, A. B.

    2016-03-01

    We are performing scaled astrophysics experiments on Omega and on NIF. Laser driven counter-streaming interpenetrating supersonic plasma flows can be studied to understand astrophysical electromagnetic plasma phenomena in a controlled laboratory setting. In our Omega experiments, the counter-streaming flow plasma state is measured using Thomson scattering diagnostics, demonstrating the plasma flows are indeed super-sonic and in the collisionless regime. We observe a surprising additional electron and ion heating from ion drag force in the double flow experiments that are attributed to the ion drag force and electrostatic instabilities. [1] A proton probe is used to image the electric and magnetic fields. We observe unexpected large, stable and reproducible electromagnetic field structures that arise in the counter-streaming flows [2]. The Biermann battery magnetic field generated near the target plane, advected along the flows, and recompressed near the midplane explains the cause of such self-organizing field structures [3]. A D3He implosion proton probe image showed very clear filamentary structures; three-dimensional Particle-In-Cell simulations and simulated proton radiography images indicate that these filamentary structures are generated by Weibel instabilities and that the magnetization level (ratio of magnetic energy over kinetic energy in the system) is ∼0.01 [4]. These findings have very high astrophysical relevance and significant implications. We expect to observe true collisionless shock formation when we use >100 kJ laser energy on NIF.

  6. Dimensioning IRGA gas sampling systems: laboratory and field experiments

    NASA Astrophysics Data System (ADS)

    Aubinet, Marc; Joly, Lilian; Loustau, Denis; De Ligne, Anne; Chopin, Henri; Cousin, Julien; Chauvin, Nicolas; Decarpenterie, Thomas; Gross, Patrick

    2016-03-01

    Both laboratory and field experiments were carried out in order to define suitable configuration ranges for the gas sampling systems (GSSs) of infrared gas analyzers (IRGAs) used in eddy covariance measurements.

    In the laboratory, an original dynamic calibration bench was developed in order to test the frequency attenuation and pressure drop generated by filters. In the field, three IRGAs of the same type equipped with different filters or different rain caps were installed and run and the real frequency response of the complete setup was tested. The main results are as follows. - Filters may have a strong impact on the pressure drop in the GSS and this impact increases with flow rate. - Conversely, no impact of the tested filters on cut-off frequency was found, GSSs with and without filters presenting similar cut-off frequencies. - The main limiting factor of cut-off frequency in the field was found to be the rain cap design. In addition, the impact of this design on pressure drop was also found to be noteworthy.

  7. Dimensioning IRGA gas sampling system : laboratory and field experiments

    NASA Astrophysics Data System (ADS)

    Aubinet, Marc; Joly, Lilian; Loustau, Denis; De Ligne, Anne; Chopin, Henri; Cousin, Julien; De Carpenterie, Thomas; Gross, Patrick; Chauvin, Nicolas

    2016-04-01

    Both laboratory and field experiments were carried out in order to define suitable configuration ranges for the gas sampling systems (GSS) of infrared gas analyzers (IRGA) used in eddy covariance measurements. In the laboratory, an original dynamic calibration bench was developed in order to test the frequency attenuation and pressure drop generated by filters. In the field, three IRGAs of the same type equipped with different filters or different rain caps were installed and run and the real frequency response of the complete set-up was tested. The main results are that: - Filters may have a strong impact on the pressure drop in the GSS and this impact increases with flow rate. - On the contrary, no impact of the tested filters on cut off frequency was found, GSS with and without filters presenting similar cut off frequencies. - The main limiting factor of cut off frequency in the field was found to be the rain cap design. In addition, the impact of this design on pressure drop was also found noteworthy.

  8. Unsteady magnetic reconnection in laboratory experiments with current sheets

    NASA Astrophysics Data System (ADS)

    Frank, Anna

    2009-11-01

    According to present notion, unsteady magnetic reconnection in current sheets (CS) is basic to dramatic natural phenomena: solar and stellar flares, substorms in the Earth and other planetary magnetospheres, as well as to disruptive instabilities in tokamak plasmas. We present a review of laboratory experiments studying evolution of CS formed in 3D and 2D magnetic configurations with an X line, in the CS-3D device. Usually CS exists during an extended period in a metastable stage, without essential changes of its structure and parameters. Under certain conditions this stage may be suddenly interrupted by unsteady phase of magnetic reconnection, which manifests itself in a rapid change of the magnetic field topology, current redistribution, excitation of pulsed electric fields, and other dynamic effects. The unsteady phase results in effective conversion of magnetic energy into the energy of plasma and accelerated particles, and may finally bring about the CS disruption. In the context of the solar flares, a metastable CS is associated with a pre-flare situation, while CS disruption -- with the flare itself. The physical mechanisms triggering the unsteady magnetic reconnection in the laboratory produced current sheets are discussed. Supported by the Russian Foundation for Basic Research (project # 09-02-00971).

  9. Magnetic shielding of a laboratory Hall thruster. II. Experiments

    SciTech Connect

    Hofer, Richard R. Goebel, Dan M.; Mikellides, Ioannis G.; Katz, Ira

    2014-01-28

    The physics of magnetic shielding in Hall thrusters were validated through laboratory experiments demonstrating essentially erosionless, high-performance operation. The magnetic field near the walls of a laboratory Hall thruster was modified to effectively eliminate wall erosion while maintaining the magnetic field topology away from the walls necessary to retain efficient operation. Plasma measurements at the walls validate our understanding of magnetic shielding as derived from the theory. The plasma potential was maintained very near the anode potential, the electron temperature was reduced by a factor of two to three, and the ion current density was reduced by at least a factor of two. Measurements of the carbon backsputter rate, wall geometry, and direct measurement of plasma properties at the wall indicate that the wall erosion rate was reduced by a factor of 1000 relative to the unshielded thruster. These changes effectively eliminate wall erosion as a life limitation in Hall thrusters, enabling a new class of deep-space missions that could not previously be attempted.

  10. The Nature of Laboratory Learning Experiences in Secondary Science Online

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

    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.

  11. A Simple Laboratory Experiment to Measure e/k

    NASA Astrophysics Data System (ADS)

    Inman, Fred

    2005-01-01

    The measurement of fundamental constants is common practice in instructional laboratories. A number of the equipment manufacturers have developed apparatus for such applications, e.g., the determination of e by the Millikan oil drop method or the determination of the speed of light with fiber optics. Other experiments determine not a single constant, but a combination of constants, e.g., e/m by electron beam deflection in a magnetic field or h/e by the photoelectric effect. About 30 years ago Carl E. Miller and I proposed a method of measuring e/k, the ratio of the electron charge to Boltzmann's constant, that was reasonably simple but not necessarily inexpensive because it involved the use of a sensitive electrometer. In recent years, however, inexpensive digital multimeters (DMM), many costing less than 30, have found their way into the physics laboratory. The purpose of this paper is to suggest the use of two DMMs, one operating as a voltmeter and the other as an ammeter, in a simple circuit involving a junction transistor and a variable potential source. Even the potential source can be quite simple, a 1.5-V battery and a 1-kΩ potentiometer, as shown in Fig. 1. If available, a variable dc power supply replacing the battery and potentiometer would be more convenient.

  12. Understanding Mixing and Entrainment of Oceanic Overflows Using Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Ecke, R. E.; Odier, P.; Chen, J.; Rivera, M. K.

    2007-12-01

    Oceanic overflows are important elements of the Earth's global thermohaline circulation but the mixing and entrainment that occur for such overflows is poorly understood. In particular, as overflow water moves down an inclined slope its stability is governed by the competition between stratification, which stabilizes the flow, and vertical shear, which tends to destabilize the flow. The properties of our laboratory experiment are designed to mimic oceanic overflows to the extent achievable on laboratory-accessible length scales. The flow exits a nozzle and flows along an inclined plane such that there is gravitational forcing of the flowing gravity current. We inject turbulent velocity fluctuations into the fluid using an active rotating grid prior to its exit from the nozzle, thereby generating a turbulent boundary layer condition at the plane boundary. The Taylor Reynolds number of the flow coming out of the nozzle is about 150. Velocity and density fields are measured simultaneous using particle image velocimetry and planar laser induced fluorescence. The flow structure and dynamics of mixing at different downstream locations are investigated for a standard stratified case and a non-stratified case where there is no density difference between the injected current and the ambient fluid. The role of turbulence is examined by comparing cases of turbulent and the laminar gravity currents. The implication of these results for ocean simulations will be presented.

  13. Laboratory astrophysical collisionless shock experiments with interpenetrating plasma flows on Omega and NIF

    NASA Astrophysics Data System (ADS)

    Ross, James; Park, H.-S.; Huntington, C.; Ryutov, D.; Drake, R. P.; Froula, D.; Gregori, G.; Levy, M.; Lamb, D.; Fiuza, F.; Petrasso, R.; Li, C.; Zylastra, A.; Rinderknecht, H.; Sakawa, Y.; Spitkovsky, A.

    2015-11-01

    Shock formation from high-Mach number plasma flows is observed in many astrophysical objects such as supernova remnants and gamma ray bursts. These are collisionless shocks as the ion-ion collision mean free path is much larger than the system size. It is believed that seed magnetic fields can be generated on a cosmologically fast timescale via the Weibel instability when such environments are initially unmagnetized. Here we present laboratory experiments using high-power lasers whose ultimate goal is to investigate the dynamics of collisionless shock formation in two interpenetrating plasma streams. Particle-in-cell numerical simulations have confirmed that the strength and structure of the generated magnetic field are consistent with the Weibel mediated electromagnetic nature and that the inferred magnetization level could be as high as ~ 1%. This paper will review recent experimental results from various laser facilities as well as the simulation results and the theoretical understanding of these observations. Taken together, these results imply that electromagnetic instabilities can be significant in both inertial fusion and astrophysical conditions. We will present results from initial NIF experiments, where we observe the neutrons and x-rays generated from the hot plasmas at the center of weakly collisional, counterstreaming flows. Prepared by LLNL under Contract DE-AC52-07NA27344.

  14. Seeded FEL Microbunching Experiments at the UCLA Neptune Laboratory

    SciTech Connect

    Tochitsky, S. Ya.; Musumeci, P.; Rosenzweig, J. B.; Joshi, C.; Gottschalk, S. C.

    2010-11-04

    Seeded high-gain FELs, which can generate very powerful radiation pulses in a relatively compact undulator and simultaneously modulate the electron beam longitudinally at the seed wavelength, are important tools for advanced accelerator development. A single-pass 0.5-9 THz FEL amplifier-buncher driven by a regular photoinjector is being built at the UCLA Neptune Laboratory. FEL interactions at 340 {mu}m (1 THz) are considered for the first experiment, since time-resolved measurements of longitudinal current distribution of the bunched beam using the RF deflecting cavity are possible. A design of a 0.2-2.0 {mu}m FEL using the same undulators is presented. In this case the FEL is driven by a high-peak current beam from the laser-plasma accelerator tunable in the 100-300 MeV range.

  15. Slew maneuvers of Spacecraft Control Laboratory Experiment (SCOLE)

    NASA Technical Reports Server (NTRS)

    Kakad, Yogendra P.

    1992-01-01

    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.

  16. Deformation Monitoring of Materials Under Stress in Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Skarlatos, D.; Yiatros, S.

    2016-06-01

    Photogrammetry is a valid alternative solution to linear variable differential transformer (LVDT) measurements in structural testing in laboratory conditions. Although the use of LVDTs boasts a high degree of accuracy, on the other hand it is limiting as it offers measurements between two points and it thus might be unable to capture localized deformations and strains over a bigger area of a structural specimen. In this aspect photogrammetry seems to offer certain advantages. Commercial solutions provide limited testing envelopes, while on the other hand, the wide range on new materials need more versatile techniques. Based on the need to develop an in-house photogrammetric toolbox to support several structural and material experiments in the department Advanced Pore Morphology (APM) aluminium foam specimens developed at Fraunhofer IFAM in Germany and cured at CUT, were tested under monotonic compressive load. Data acquisition, analysis and results, along with lessons learnt from the process are presented in this work.

  17. LABORATORY EXPERIMENTS TO SIMULATE CO2 OCEAN DISPOSAL

    SciTech Connect

    Stephen M. Masutani

    1999-12-31

    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.

  18. Experimenting in a constructivist high school physics laboratory

    NASA Astrophysics Data System (ADS)

    Roth, Wolff-Michael

    Although laboratory activities have long been recognized for their potential to facilitate the learning of science concepts and skills, this potential has yet to be realized. To remediate this problem, researchers have called for constructivist learning environments in which students can pursue open inquiry and frame their own research problems. The present study was designed to describe and understand students' experimenting and problem solving in such an environment. An interpretive research methodology was adopted for the construction of meaning from the data. The data sources included videotapes, their transcripts, student laboratory reports and reflections, interviews with the students, and the teacher's course outline and reflective notes. Forty-six students from three sections of an introductory physics course taught at a private school for boys participated in the study. This article shows the students' remarkable ability and willingness to generate research questions and to design and develop apparatus for data collection. In their effort to frame research questions, students often used narrative explanations to explore and think about the phenomena to be studied. In some cases, blind alleys, students framed research questions and planned experiments that did not lead to the expected results. We observed a remarkable flexibility to deal with problems that arose during the implementation of their plans in the context of the inquiry. These problems, as well as their solutions and the necessary decision-making processes, were characterized by their situated nature. Finally, students pursued meaningful learning during the interpretation of data and graphs to arrive at reasonable answers of their research questions. We concluded that students should be provided with problem-rich learning environments in which they learn to investigate phenomena of their own interest and in which they can develop complex problem-solving skills.

  19. Rainfall estimation using moving cars as rain gauges - laboratory experiments

    NASA Astrophysics Data System (ADS)

    Rabiei, E.; Haberlandt, U.; Sester, M.; Fitzner, D.

    2013-04-01

    The spatial assessment of short time step precipitation is a challenging task. Low density of observation networks, as well as the bias in radar rainfall estimation motivated the new idea of exploiting cars as moving rain gauges with windshield wipers or optical sensors as measurement devices. In a preliminary study, this idea has been tested with computer experiments (Haberlandt and Sester, 2010). The results have shown that a high number of possibly inaccurate measurement devices (moving cars) provide more reliable areal rainfall estimations than a lower number of precise measurement devices (stationary gauges). Instead of assuming a relationship between wiper frequency (W) and rainfall intensity (R) with an arbitrary error, the main objective of this study is to derive valid W-R relationships between sensor readings and rainfall intensity by laboratory experiments. Sensor readings involve the wiper speed, as well as optical sensors which can be placed on cars and are usually made for automating wiper activities. A rain simulator with the capability of producing a wide range of rainfall intensities is designed and constructed. The wiper speed and two optical sensors are used in the laboratory to measure rainfall intensities, and compare it with tipping bucket readings as reference. Furthermore, the effect of the car speed on the estimation of rainfall using a car speed simulator device is investigated. The results show that the sensor readings, which are observed from wiper speed adjustment according to the front visibility, can be considered as a strong indicator for rainfall intensity. Also the optical sensors showed promising results toward measuring rainfall rate. It is observed that the car speed has a significant effect on the rainfall measurement. This effect is highly dependent on the rain type as well as the windshield angle.

  20. Rainfall estimation using moving cars as rain gauges - laboratory experiments

    NASA Astrophysics Data System (ADS)

    Rabiei, E.; Haberlandt, U.; Sester, M.; Fitzner, D.

    2013-11-01

    The spatial assessment of short time-step precipitation is a challenging task. Low density of observation networks, as well as the bias in radar rainfall estimation motivated the new idea of exploiting cars as moving rain gauges with windshield wipers or optical sensors as measurement devices. In a preliminary study, this idea has been tested with computer experiments (Haberlandt and Sester, 2010). The results have shown that a high number of possibly inaccurate measurement devices (moving cars) provide more reliable areal rainfall estimations than a lower number of precise measurement devices (stationary gauges). Instead of assuming a relationship between wiper frequency (W) and rainfall intensity (R) with an arbitrary error, the main objective of this study is to derive valid W-R relationships between sensor readings and rainfall intensity by laboratory experiments. Sensor readings involve the wiper speed, as well as optical sensors which can be placed on cars and are usually made for automating wiper activities. A rain simulator with the capability of producing a wide range of rainfall intensities is designed and constructed. The wiper speed and two optical sensors are used in the laboratory to measure rainfall intensities, and compare it with tipping bucket readings as reference. Furthermore, the effect of the car speed on the estimation of rainfall using a car speed simulator device is investigated. The results show that the sensor readings, which are observed from manual wiper speed adjustment according to the front visibility, can be considered as a strong indicator for rainfall intensity, while the automatic wiper adjustment show weaker performance. Also the sensor readings from optical sensors showed promising results toward measuring rainfall rate. It is observed that the car speed has a significant effect on the rainfall measurement. This effect is highly dependent on the rain type as well as the windshield angle.

  1. Studying collisions in the general physics laboratory with quadrature light emitting diode sensors

    NASA Astrophysics Data System (ADS)

    DeYoung, P. A.; Mulder, B.

    2002-12-01

    We have developed the means to measure position rapidly and precisely as a function of time in the general physics laboratory. These measurements are of sufficient quality that velocities and accelerations can be calculated from the position data using numerical derivatives. The precision of the measurements is such that any disagreement between theoretical expectations and experimental measurements is less than a few percent. Measurements of the system under study can be made as rapidly as every 200 μs, which is faster than the typical time scales over which the system changes. Measuring rapidly also allows one to investigate additional phenomena not previously accessible and to see features of the physics previously unobserved. The measurement system is based on commercially available sensors, computer hardware, and computer software (LABVIEW™). Many general physics laboratories based on this system have been developed but only an investigation of Newton's second law will be described here.

  2. Laboratory Experiments Modelling Sediment Transport by River Plumes

    NASA Astrophysics Data System (ADS)

    Sutherland, Bruce; Gingras, Murray; Knudson, Calla; Steverango, Luke; Surma, Chris

    2016-11-01

    Through lock-release laboratory experiments, the transport of particles by hypopycnal (surface) currents is examined as they flow into a uniform-density and a two-layer ambient fluid. In most cases the tank is tilted so that the current flows over a slope representing an idealization of a sediment-bearing river flowing into the ocean and passing over the continental shelf. When passing into a uniform-density ambient, the hypopycnal current slows and stops as particles rain out, carrying some of the light interstitial fluid with them. Rather than settling on the bottom, in many cases the descending particles accumulate to form a hyperpycnal (turbidity) current that flows downslope. This current then slows and stops as particles both rain out to the bottom and also rise again to the surface, carried upward by the light interstitial fluid. For a hypopycnal current flowing into a two-layer fluid, the current slows as particles rain out and accumulate at the interface of the two-layer ambient. Eventually these particles penetrate through the interface and settle to the bottom with no apparent formation of a hyperpycnal current. Analyses are performed to characterize the speed of the currents and stopping distances as they depend upon experiment parameters. Natural Sciences and Engineering Research Council.

  3. Photocatalytic Hydrogen Production by Direct Sunlight: A Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Koca, Atif; Sahin, Musa

    2003-11-01

    The demand for hydrogen will increase within the next decades as a result of the necessity to produce clean and environmentally and economically accepted fuels from natural and renewable energy resources. In principle, hydrogen has the potential to play an important role in future energy systems because of the diversity of its applications, the variety of ways in which it can be stored, its general environmental advantages, and especially because of the possibility of producing hydrogen by splitting water using photocatalysts and solar energy. Methods and techniques of photocatalytic reactions are covered in some detail in many undergraduate chemistry programs. However, many times in instructional settings, little attention is given to how it is used for the production of hydrogen. In the present investigation a photocatalytic hydrogen production experiment suitable for use in undergraduate chemistry laboratories is described. The experiment can be used to introduce students to the concept of a renewable and sustainable hydrogen energy system of the future, as well as its production techniques, and to demonstrate the use of a CdS/ZnS photocatalyst system for photocatalytic hydrogen production from direct sunlight.

  4. Recording the PHILAE Touchdown using CASSE: Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Knapmeyer, Martin; Faber, Claudia; Tune, Jean-Baptiste; Arnold, Walter; Witte, Lars; Schröder, Silvio; Roll, Reinhard; Chares, Bernd; Fischer, Hans-Herbert; Möhlmann, Diedrich; Seidensticker, Klaus

    2014-05-01

    The landing of Philae on comet 67P/Churyumov-Gerasimenko is scheduled for November 11, 2014. Its landing feet house the triaxial acceleration sensors of CASSE (Comet Acoustic Surface Sounding Experiment) 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. The qualification model of the Philae landing gear was used in the tests. It consists of three legs manufactured of carbon fiber and metal joints. Attached to each leg is a foot with two soles and a mechanically driven ice screw to secure the lander on the comet. The right one of these soles, if viewed from the outside towards the lander body, houses a Brüel & Kjaer DeltaTron 4506 triaxial piezoelectric accelerometer as used on the spacecraft. Orientation of the three axes was such that the X-axis of the accelerometer points downwards while the Y and Z axes are horizontal. This somewhat uncommon orientation was necessary due to the position of the electric connector on the 4506. Data was recorded at a sampling rate of 8.2 kHz for a duration of 2 s. Touchdown measurements were conducted on three types of ground with different landing velocities. Landings with low velocities were carried out on the concrete floor of the LAMA to determine the stiffness of the landing gear based on the deceleration data measured with the accelerometer. Landings on fine

  5. Hydration Energies of Zinc(II): Threshold Collision-Induced Dissociation Experiments and Theoretical Studies

    NASA Astrophysics Data System (ADS)

    Cooper, Theresa E.; Carl, D. R.; Armentrout, P. B.

    2009-11-01

    The first experimentally determined sequential bond dissociation energies of Zn2+(H2O)n complexes, where n = 6-10, are measured using threshold collision-induced dissociation in a guided ion beam tandem mass spectrometer coupled with an electrospray ionization source. Kinetic energy dependent cross sections are obtained and analyzed to yield 0 K threshold measurements for the loss of one and two water ligands after accounting for multiple collisions, kinetic shifts, and energy distributions. The threshold measurements are then converted from 0 to 298 K values to give the hydration energies for sequentially losing one water from each parent complex. Theoretical geometry optimizations and single-point energy calculations are performed using several levels of theory for comparison to experiment. Although different levels of theory disagree on the ground-state conformation of most complexes examined here leading to potential ambiguities in the final thermochemical values, calculations at the MP2(full) level provide the best agreement with experiment. On this basis, the present experiments are most consistent with the inner solvent shell of Zn2+ being five waters, except for Zn2+(H2O)6 where all waters bind directly to the metal ion. The charge separation process, Zn2+(H2O)n → ZnOH+(H2O)m + H+(H2O)n-m-1, which is in competition with the loss of water from the parent complex, is also observed for n = 6-8. These processes are analyzed in detail in the following paper.

  6. Laboratory Experiments On Continually Forced 2d Turbulence

    NASA Astrophysics Data System (ADS)

    Wells, M. G.; Clercx, H. J. H.; Van Heijst, G. J. F.

    There has been much recent interest in the advection of tracers by 2D turbulence in geophysical flows. While there is a large body of literature on decaying 2D turbulence or forced 2D turbulence in unbounded domains, there have been very few studies of forced turbulence in bounded domains. In this study we present new experimental results from a continuously forced quasi 2D turbulent field. The experiments are performed in a square Perspex tank filled with water. The flow is made quasi 2D by a steady background rotation. The rotation rate of the tank has a small (<8 %) sinusoidal perturbation which leads to the periodic formation of eddies in the corners of the tank. When the oscillation period of the perturbation is greater than an eddy roll-up time-scale, dipole structures are observed to form. The dipoles can migrate away from the walls, and the interior of the tank is continually filled with vortexs. From experimental visualizations the length scale of the vortexs appears to be largely controlled by the initial formation mechanism and large scale structures are not observed to form at large times. Thus the experiments provide a simple way of cre- ating a continuously forced 2D turbulent field. The resulting structures are in contrast with most previous laboratory experiments on 2D turbulence which have investigated decaying turbulence and have observed the formations of large scale structure. In these experiments, decaying turbulence had been produced by a variety of methods such as the decaying turbulence in the wake of a comb of rods (Massen et al 1999), organiza- tion of vortices in thin conducting liquids (Cardoso et al 1994) or in rotating systems where there are sudden changes in angular rotation rate (Konijnenberg et al 1998). Results of dye visualizations, particle tracking experiments and a direct numerical simulation will be presented and discussed in terms of their oceanographic application. Bibliography Cardoso,O. Marteau, D. &Tabeling, P

  7. iPads in the Science Laboratory: Experience in Designing and Implementing a Paperless Chemistry Laboratory Course

    ERIC Educational Resources Information Center

    Hesser, Tiffany L.; Schwartz, Pauline M.

    2013-01-01

    In the fall of 2012, 20 General Chemistry Honors students at the University of New Haven were issued the new iPad 3 to incorporate these devices both in the classroom and the laboratory. This paper will focus on the integration of the iPad into the laboratory curriculum while creating a paperless experience, an environment where no paper would…

  8. Central Exclusive Production in Proton-Proton Collisions with the STAR Experiment at RHIC

    NASA Astrophysics Data System (ADS)

    Guryn, Włodek

    2016-07-01

    We shall describe the physics program with tagged forward protons, focusing on Central Exclusive Production in polarized proton-proton collisions at the Relativistic Heavy Ion Collider (RHIC), with the STAR detector at √s = 200 GeV. Preliminary results in CEP of two oppositely charged pions and kaons produced in the processes pp → ppπ+π- and pp → ppK+K- shall be presented. Those Double Pomeron Exchange (DPE) processes, allow the final states to be dominated by gluonic exchanges. Silicon strip detectors placed in Roman Pots were used for measuring forward protons. The preliminary results are based on the measurement of the recoil system of charged particles in the STAR experiment's Time Projection Chamber (TPC). Ionization energy loss, dE/dx, of charged particles was used for particle identification (PID).

  9. The digital computer as a metaphor for the perfect laboratory experiment: Loophole-free Bell experiments

    NASA Astrophysics Data System (ADS)

    De Raedt, Hans; Michielsen, Kristel; Hess, Karl

    2016-12-01

    Using Einstein-Podolsky-Rosen-Bohm experiments as an example, we demonstrate that the combination of a digital computer and algorithms, as a metaphor for a perfect laboratory experiment, provides solutions to problems of the foundations of physics. Employing discrete-event simulation, we present a counterexample to John Bell's remarkable "proof" that any theory of physics, which is both Einstein-local and "realistic" (counterfactually definite), results in a strong upper bound to the correlations that are being measured in Einstein-Podolsky-Rosen-Bohm experiments. Our counterexample, which is free of the so-called detection-, coincidence-, memory-, and contextuality loophole, violates this upper bound and fully agrees with the predictions of quantum theory for Einstein-Podolsky-Rosen-Bohm experiments.

  10. Emulating JWST Exoplanet Transit Observations in a Testbed laboratory experiment

    NASA Astrophysics Data System (ADS)

    Touli, D.; Beichman, C. A.; Vasisht, G.; Smith, R.; Krist, J. E.

    2014-12-01

    The transit technique is used for the detection and characterization of exoplanets. The combination of transit and radial velocity (RV) measurements gives information about a planet's radius and mass, respectively, leading to an estimate of the planet's density (Borucki et al. 2011) and therefore to its composition and evolutionary history. Transit spectroscopy can provide information on atmospheric composition and structure (Fortney et al. 2013). Spectroscopic observations of individual planets have revealed atomic and molecular species such as H2O, CO2 and CH4 in atmospheres of planets orbiting bright stars, e.g. Deming et al. (2013). The transit observations require extremely precise photometry. For instance, Jupiter transit results to a 1% brightness decrease of a solar type star while the Earth causes only a 0.0084% decrease (84 ppm). Spectroscopic measurements require still greater precision <30ppm. The Precision Projector Laboratory (PPL) is a collaboration between the Jet Propulsion Laboratory (JPL) and California Institute of Technology (Caltech) to characterize and validate detectors through emulation of science images. At PPL we have developed a testbed to project simulated spectra and other images onto a HgCdTe array in order to assess precision photometry for transits, weak lensing etc. for Explorer concepts like JWST, WFIRST, EUCLID. In our controlled laboratory experiment, the goal is to demonstrate ability to extract weak transit spectra as expected for NIRCam, NIRIS and NIRSpec. Two lamps of variable intensity, along with spectral line and photometric simulation masks emulate the signals from a star-only, from a planet-only and finally, from a combination of a planet + star. Three masks have been used to simulate spectra in monochromatic light. These masks, which are fabricated at JPL, have a length of 1000 pixels and widths of 2 pixels, 10 pixels and 1 pixel to correspond respectively to the noted above JWST instruments. From many-hour long

  11. Safety in the Chemical Laboratory: Experiments Integrating Evaluation of Chemical Hazards into the Chemistry Curriculum.

    ERIC Educational Resources Information Center

    Pierce, J. T.; And Others

    1984-01-01

    Proposes use of two experiments to sample and analyze contaminents in the laboratory. Experiments focus on estimating hydrogen sulfide levels in the general chemistry laboratory during qualitative analysis and determining the concentration of organic vapors associated with organic chemistry laboratories. (JN)

  12. Laboratory experiments for estimating chemical osmotic parameters of mudstones

    NASA Astrophysics Data System (ADS)

    Miyoshi, S.; Tokunaga, T.; Mogi, K.; Ito, K.; Takeda, M.

    2010-12-01

    Recent studies have quantitatively shown that mudstone can act as semi-permeable membrane and can generate abnormally high pore pressure in sedimentary basins. Reflection coefficient is one of the important properties that affect the chemical osmotic behavior of mudstones. However, not many quantitative studies on the reflection coefficient of mudstones have been done. We have developed a laboratory apparatus to observe chemical osmotic behavior, and a numerical simulation technique to estimate the reflection coefficient and other relating properties of mudstones. A core sample of siliceous mudstone obtained from the drilled core at Horonobe, Japan, was set into the apparatus and was saturated by 0.1mol/L sodium chloride solution. Then, the up-side reservoir was replaced with 0.05mol/L sodium chloride solution, and temporal changes of both pressure and concentration of the solution in both up-side and bottom-side reservoirs were measured. Using the data obtained from the experiment, we estimated the reflection coefficient, effective diffusion coefficient, hydraulic conductivity, and specific storage of the sample by fitting the numerical simulation results with the observed ones. A preliminary numerical simulation of groundwater flow and solute migration was conducted in the area where the core sample was obtained, using the reflection coefficient and other properties obtained from this study. The result suggested that the abnormal pore pressure observed in the region can be explained by the chemical osmosis.

  13. Cometary Materials Originating from Interstellar Ices: Clues from Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Fresneau, A.; Abou Mrad, N.; d’Hendecourt, L. LS; Duvernay, F.; Flandinet, L.; Orthous-Daunay, F.-R.; Vuitton, V.; Thissen, R.; Chiavassa, T.; Danger, G.

    2017-03-01

    We use laboratory experiments to derive information on the chemistry occurring during the evolution of astrophysical ices from dense molecular clouds to interplanetary objects. Through a new strategy that consists of coupling very high resolution mass spectrometry and infrared spectroscopy (FT-IR), we investigate the molecular content of the organic residues synthesized from different initial ice compositions. We also obtain information on the evolution of the soluble part of the residues after their over-irradiation. The results give insight into the role of water ice as a trapping and diluting agent during the chemical evolution. They also give information about the importance of the amount of ammonia in such ices, particularly regarding its competition with the carbon chemistry. All of these results allow us to build a first mapping of the evolution of soluble organic matter based on its chemical and physical history. Furthermore, our results suggest that interstellar ices should lead to organic materials enriched in heteroatoms that present similarities with cometary materials but strongly differ from meteoritic organic material, especially in their C/N ratios.

  14. Dynamics of spacecraft control laboratory experiment (SCOLE) slew maneuvers

    NASA Technical Reports Server (NTRS)

    Kakad, Y. P.

    1987-01-01

    This is the first of two reports on the dynamics and control of slewing maneuvers of the NASA Spacecraft Control Laboratory Experiment (SCOLE). In this report, the dynamics of slewing maneuvers of SCOLE are developed in terms of an arbitrary maneuver about any given axis. 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 interaction between the rigid shuttle and the flexible appendage. The final set of dynamical equations obtained for slewing maneuvers is highly nonlinear and coupled in terms of the flexible modes and the rigid-body modes. The equations are further simplified and evaluated numerically to include the first ten flexible modes and the SCOLE data to yield a model for designing control systems to perform slew maneuvers.

  15. New Laboratory-Based Satellite Impact Experiments for Breakup Fragment Characterization

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Fitz-Coy, N.; Dikova, R.; Wilson, M.; Huynh, T.; Sorge, M.; Sheaffer, P.; Opiela, J.; Cowardin, H.; Krisko, P.; Rushing, R.; Nolen, M.; Roebuck, B.

    2014-01-01

    A consortium consisting of the NASA Orbital Debris Program Office, U.S. Air Force's Space and Missile Systems Center, the Aerospace Corporation, and University of Florida is planning a series of hypervelocity impact experiments on mockup targets at the U.S. Air Force's Arnold Engineering Development Complex (AEDC) in early 2014. The target for the first experiment resembles a rocket upper stage whereas the target for the second experiment represents a typical 60-cm/50-kg class payload that incorporates modern spacecraft materials and components as well as exterior wrap of multi-layer insulation and three solar panels. The projectile is designed with the maximum mass that AEDC's Range G two-stage light gas gun can accelerate to an impact speed of 7 km/sec. The impact energy is expected to be close to 15 MJ to ensure catastrophic destruction of the target after the impact. Low density foam panels are installed inside the target chamber to slow down and soft-catch the fragments for post-impact processing. Diagnostic instruments, such as x-ray and high speed optical cameras, will also be used to record the breakup process. The main goal of this "DebriSat" project is to characterize the physical properties, including size, mass, shape, and density distributions, of orbital debris that would be generated by a hypervelocity collision involving an upper stage or a modern satellite in the low Earth orbit environment. In addition, representative fragments will be selected for laboratory optical and radar measurements to allow for better interpretation of data obtained by telescope and radar observations. This paper will provide a preliminary report of the impact results and the plans to process, measure, and analyze the fragments.

  16. New Laboratory-Based Satellite Impact Experiments for Breakup Fragment Characterization

    NASA Astrophysics Data System (ADS)

    Liou, J.-C.

    A consortium consisting of the NASA Orbital Debris Program Office, U.S. Air Force’s Space and Missile Systems Center, The Aerospace Corporation, and University of Florida is planning a series of hypervelocity impact experiments on mockup targets at the U.S. Air Force’s Arnold Engineering Development Complex (AEDC) in early 2014. The target for the first experiment resembles a rocket upper stage whereas the target for the second experiment represents a typical 60-cm/50-kg class payload that incorporates modern spacecraft materials and components as well as exterior wrap of multi-layer insulation and three solar panels. The projectile is designed with the maximum mass that AEDC’s Range G two-stage light gas gun can accelerate to an impact speed of 7 km/sec. The impact energy is expected to be close to 15 MJ to ensure catastrophic destruction of the target after the impact. Low density foam panels are installed inside the target chamber to slow down and soft-catch the fragments for post-impact processing. Diagnostic instruments, such as x-ray and high speed optical cameras, will also be used to record the breakup process. The main goal of this “DebriSat” project is to characterize the physical properties, including size, mass, shape, and density distributions, of orbital debris that would be generated by a hypervelocity collision involving an upper stage or a modern satellite in the low Earth orbit environment. In addition, representative fragments will be selected for laboratory optical and radar measurements to allow for better interpretation of data obtained by telescope and radar observations. This paper will provide a preliminary report of the impact results and the plans to process, measure, and analyze the fragments.

  17. DebriSat - A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterization

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Fitz-Coy, N.; Werremeyer, M.; Huynh, T.; Voelker, M.; Opiela, J.

    2012-01-01

    DebriSat is a planned laboratory ]based satellite hypervelocity impact experiment. The goal of the project is to characterize the orbital debris that would be generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 's US Navy Transit satellite. There are three phases to this project: the design and fabrication of an engineering model representing a modern, 50-cm/50-kg class LEO satellite known as DebriSat; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area ]to ]mass ratio, density, shape, material composition, optical properties, and radar cross ]section distributions, will be used to supplement the DoD fs and NASA fs satellite breakup models to better describe the breakup outcome of a modern satellite. Updated breakup models will improve mission planning, environmental models, and event response. The DebriSat project is sponsored by the Air Force fs Space and Missile Systems Center and the NASA Orbital Debris Program Office. The design and fabrication of DebriSat is led by University of Florida with subject matter experts f support from The Aerospace Corporation. The major milestones of the project include the complete fabrication of DebriSat by September 2013, the hypervelocity impact of DebriSat at the Air Force fs Arnold Engineering Development Complex in early 2014, and fragment characterization and data analyses in late 2014.

  18. Near surface geophysical techniques on subsoil contamination: laboratory experiments

    NASA Astrophysics Data System (ADS)

    Capozzoli, Luigi; Giampaolo, Valeria; Rizzo, Enzo

    2016-04-01

    Hydrocarbons contamination of soil and groundwater has become a serious environmental problem, because of the increasing number of accidental spills caused by human activities. The starting point of any studies is the reconstruction of the conceptual site model. To make valid predictions about the flow pathways following by hydrocarbons compound is necessary to make a correct reconstruction of their characteristics and the environment in which they move. Near-surface geophysical methods, based on the study of electrical and electromagnetic properties, are proved to be very useful in mapping spatial distribution of the organic contaminants in the subsurface. It is well known, in fact, that electrical properties of the porous media are significantly influenced by hydrocarbons because, when contaminants enter the rock matrix, surface reaction occur between the contaminant and the soil grain surface. The main aim of this work is to investigate the capability of near-surface geophysical methods in mapping and monitoring spatial distribution of contaminants in a controlled setting. A laboratory experiment has been performed at the Hydrogeosite Laboratory of CNR-IMAA (Marsico Nuovo, PZ) where a box-sand has been contaminated by diesel. The used contaminant is a LNAPL, added to the sand through a drilled pipe. Contaminant behaviour and its migration paths have been monitored for one year by Electrical Resistivity measurements. In details, a Cross Borehole Electrical Resistivity Tomography techniques were used to characterize the contamination dynamics after a controlled hydrocarbon spillage occurring in the vadose zone. The approach with cross-borehole resistivity imaging provide a great advantage compared to more conventional surface electrical resistivity tomography, due to the high resolution at high depth (obviously depending on the depth of the well instrumented for the acquisition). This method has been shown to provide good information on the distribution of

  19. Dilepton and φ meson production in elementary and nuclear collisions at the NICA fixed-target experiment

    NASA Astrophysics Data System (ADS)

    Wolf, György; Zétényi, Miklós

    2016-08-01

    We argue that the NICA fixed-target experiment will be able to provide very important new experimental data on dilepton and φ meson production in the basically undiscovered energy domain between the SIS and SPS energies. Experimental information about elementary cross sections in this energy region is an essential ingredient of models of nuclear collisions in the same energy range.

  20. Sampling Participants’ Experience in Laboratory Experiments: Complementary Challenges for More Complete Data Collection

    PubMed Central

    McAuliffe, Alan; McGann, Marek

    2016-01-01

    Speelman and McGann’s (2013) examination of the uncritical way in which the mean is often used in psychological research raises questions both about the average’s reliability and its validity. In the present paper, we argue that interrogating the validity of the mean involves, amongst other things, a better understanding of the person’s experiences, the meaning of their actions, at the time that the behavior of interest is carried out. Recently emerging approaches within Psychology and Cognitive Science have argued strongly that experience should play a more central role in our examination of behavioral data, but the relationship between experience and behavior remains very poorly understood. We outline some of the history of the science on this fraught relationship, as well as arguing that contemporary methods for studying experience fall into one of two categories. “Wide” approaches tend to incorporate naturalistic behavior settings, but sacrifice accuracy and reliability in behavioral measurement. “Narrow” approaches maintain controlled measurement of behavior, but involve too specific a sampling of experience, which obscures crucial temporal characteristics. We therefore argue for a novel, mid-range sampling technique, that extends Hurlburt’s descriptive experience sampling, and adapts it for the controlled setting of the laboratory. This controlled descriptive experience sampling may be an appropriate tool to help calibrate both the mean and the meaning of an experimental situation with one another. PMID:27242588

  1. Sampling Participants' Experience in Laboratory Experiments: Complementary Challenges for More Complete Data Collection.

    PubMed

    McAuliffe, Alan; McGann, Marek

    2016-01-01

    Speelman and McGann's (2013) examination of the uncritical way in which the mean is often used in psychological research raises questions both about the average's reliability and its validity. In the present paper, we argue that interrogating the validity of the mean involves, amongst other things, a better understanding of the person's experiences, the meaning of their actions, at the time that the behavior of interest is carried out. Recently emerging approaches within Psychology and Cognitive Science have argued strongly that experience should play a more central role in our examination of behavioral data, but the relationship between experience and behavior remains very poorly understood. We outline some of the history of the science on this fraught relationship, as well as arguing that contemporary methods for studying experience fall into one of two categories. "Wide" approaches tend to incorporate naturalistic behavior settings, but sacrifice accuracy and reliability in behavioral measurement. "Narrow" approaches maintain controlled measurement of behavior, but involve too specific a sampling of experience, which obscures crucial temporal characteristics. We therefore argue for a novel, mid-range sampling technique, that extends Hurlburt's descriptive experience sampling, and adapts it for the controlled setting of the laboratory. This controlled descriptive experience sampling may be an appropriate tool to help calibrate both the mean and the meaning of an experimental situation with one another.

  2. Experiments with an ion-neutral hybrid trap: cold charge-exchange collisions

    NASA Astrophysics Data System (ADS)

    Smith, W. W.; Goodman, D. S.; Sivarajah, I.; Wells, J. E.; Banerjee, S.; Côté, R.; Michels, H. H.; Mongtomery, J. A.; Narducci, F. A.

    2014-01-01

    Due to their large trap depths (˜1 eV or 10,000 K), versatility, and ease of construction, Paul traps have important uses in high-resolution spectroscopy, plasma physics, and precision measurements of fundamental constants. An ion-neutral hybrid trap consisting of two separate but spatially concentric traps [a magneto-optic trap (MOT) for the neutral species and a mass-selective linear Paul trap for the ionic species] is an ideal apparatus for sympathetic cooling. However, over the past few years, hybrid traps have proven most useful in measuring elastic and charge-exchange rate constants of ion-neutral collisions over a wide temperature range from kilo-Kelvin to nano-Kelvin. We report some initially surprising results from a hybrid trap system in our laboratory where we have loaded the Paul trap with Ca+ ions in the presence of a Na MOT (localized dense gas of cold Na atoms). We find a strong loss of Ca+ ions with MOT exposure, attributed to an exothermic, non-resonant ion-neutral charge-exchange process with an activation barrier, which leads to the formation of Na+ ions. We propose a detailed mechanism for this process. We obtain an estimated measure of the rate constant for this charge exchange of ˜2 × 10-11 cm3/s, much less than the Langevin rate, which suggests that the Langevin assumption of unit efficiency in the reaction region is not correct in this case.

  3. Collisions of Ir oxide nanoparticles with carbon nanopipettes: Experiments with one nanoparticle

    DOE PAGES

    Zhou, Min; Yu, Yun; Hu, Keke; ...

    2017-02-03

    Investigating the collisions of individual metal nanoparticles (NPs) with electrodes can provide new insights into their electrocatalytic behavior, mass transport, and interactions with surfaces. Here we report a new experimental setup for studying NP collisions based on the use of carbon nanopipettes to enable monitoring multiple collision events involving the same NP captured inside the pipet cavity. A patch clamp amplifier capable of measuring pA-range currents on the microsecond time scale with a very low noise and stable background was used to record the collision transients. The analysis of current transients produced by oxidation of hydrogen peroxide at one IrOxmore » NP provided information about the origins of deactivation of catalytic NPs and the effects of various experimental conditions on the collision dynamics. Lastly, high-resolution TEM of carbon pipettes was used to attain better understanding of the NP capture and collisions.« less

  4. An "in Silico" DNA Cloning Experiment for the Biochemistry Laboratory

    ERIC Educational Resources Information Center

    Elkins, Kelly M.

    2011-01-01

    This laboratory exercise introduces students to concepts in recombinant DNA technology while accommodating a major semester project in protein purification, structure, and function in a biochemistry laboratory for junior- and senior-level undergraduate students. It is also suitable for forensic science courses focused in DNA biology and advanced…

  5. Hands-on laboratory Experience in Teaching-Learning Physiology.

    ERIC Educational Resources Information Center

    Randall, Walter C.; Burkholder, Timothy

    1990-01-01

    The results of actual student participation, with organized group discussions, which show that laboratory teaching remains the premiere mechanism for teaching and learning organ-system physiology are discussed. Laboratories using a pithed frog, a turtle heart, an anesthetized rabbit, and noninvasive recordings from students during exercise are…

  6. Explosive Pulsed Power Experiments At The Phillips Laboratory

    DTIC Science & Technology

    1997-06-01

    Weapons and Survivability Directorate Phillips Laboratory Kirtland AFB, NM 87117 J. Graham, W. Sornrnars Albuquerque Division Maxwell Technologies... Phillips Laboratory Kirtland AFB, NM 87117 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10...pulse shaping/impedance matching systems are discussed. Introduction Air Force missions utilizing pulsed power technology increasingly require the

  7. Simulation of astrophysical jets in a laboratory experiment

    NASA Astrophysics Data System (ADS)

    Bellan, Paul

    2006-04-01

    Astrophysical jets are routinely simulated in a reproducible, well-diagnosed laboratory experiment. The experimental sequence starts by imposing a vacuum poloidal magnetic field linking a disk electrode to a co-planar annular electrode. Neutral gas (H, Ne, N, or Ar) is then injected via 8 nozzles located on the disk and 8 nozzles on the annulus. A 120 μF capacitor bank power supply charged to 4-7 kV is applied via ignitron switches across the electrodes, breaking down the injected gas to form plasma. The low impedance (<10 mφ) of the highly conducting plasma causes the power supply to behave as a current source, rather than a voltage source. The discharging capacitor bank drives a ˜100 kA poloidal electric current through the plasma; this current initially flows in eight distinct `spider legs' (see photo in April meeting poster) that span from the disk to the annulus. The spider legs quickly merge via mutual attraction of their currents to form the simulated astrophysical jet. The axial gradient of the toroidal magnetic field energy density provides the force that accelerates the jet. The mass flux boundary condition at the electrodes is tightly coupled to the jet behavior. The jet is `fueled' by plasma ingested from the nozzles and the accumulation (pile-up) of the ingested plasma collimates the jet because of the associated pile-up of frozen-in toroidal magnetic flux convected with the plasma. The jet undergoes a kink instability when it becomes long enough to satisfy the Kruskal-Shafranov q=1 condition.

  8. Previous Driving Experience, but Not Vision, Is Associated With Motor Vehicle Collision Rate in Bioptic Drivers

    PubMed Central

    Dougherty, Bradley E.; Flom, Roanne E.; Bullimore, Mark A.; Raasch, Thomas W.

    2015-01-01

    Purpose Bioptic telescopic spectacles (BTS) consist of a small telescope (or telescopes) mounted high in a pair of spectacle lenses. More than 40 states allow for some form of bioptic driving licensure for people with decreased central vision. The purpose of this study was to determine significant associations among previous driving experience, vision, and motor vehicle collisions (MVCs) for bioptic drivers in Ohio. Methods We conducted a retrospective study of patients who received a vision examination and subsequently obtained bioptic licensure. We obtained driving records from the Ohio Bureau of Motor Vehicles in order to determine MVC involvement. Relationships among vision measures, age, sex, previous experience, and MVCs were investigated using time-to-event analysis and the Cox proportional hazards regression model. Results We identified 237 bioptic drivers (65% male). Age at initial exam ranged from 16 to 81 years, and mean visual acuity was approximately 20/120. The number of MVCs per driver ranged from 0 to 11, with 124 (52%) drivers having had at least one MVC. Visual acuity and contrast sensitivity were not significant predictors of MVC. Drivers without previous driving experience were significantly more likely to have been involved in an MVC (P < 0.001), and this association remained significant after adjusting for age and sex (P = 0.01). The rate of MVC per year decreased steadily over a 10-year period for drivers without previous experience. Conclusions Previous nonbioptic driving experience, but not visual acuity or contrast sensitivity, was associated with yearly MVC rate in bioptic drivers. PMID:26436885

  9. Fluorescence quantum yield measurements of fluorescent proteins: a laboratory experiment for a biochemistry or molecular biophysics laboratory course.

    PubMed

    Wall, Kathryn P; Dillon, Rebecca; Knowles, Michelle K

    2015-01-01

    Fluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts absorbed photons into emitted photons and it is necessary to know for assessing what fluorescent protein is the most appropriate for a particular application. In this work, we have designed an upper-level, biochemistry laboratory experiment where students measure the fluorescence quantum yields of fluorescent proteins relative to a standard organic dye. Four fluorescent protein variants, enhanced cyan fluorescent protein (ECFP), enhanced green fluorescent protein (EGFP), mCitrine, and mCherry, were used, however the methods described are useful for the characterization of any fluorescent protein or could be expanded to fluorescent quantum yield measurements of organic dye molecules. The laboratory is designed as a guided inquiry project and takes two, 4 hr laboratory periods. During the first day students design the experiment by selecting the excitation wavelength, choosing the standard, and determining the concentration needed for the quantum yield experiment that takes place in the second laboratory period. Overall, this laboratory provides students with a guided inquiry learning experience and introduces concepts of fluorescence biophysics into a biochemistry laboratory curriculum.

  10. Measuring dynamical K/π and p/π fluctuations in AuAu collisions from the STAR experiment

    NASA Astrophysics Data System (ADS)

    Tarnowsky, T.

    2012-05-01

    Results from new measurements of dynamical K/π and p/π ratio fluctuations are presented. Dynamical fluctuations in global conserved quantities such as baryon number, strangeness, or charge may be observed near a QCD critical point. The STAR experiment has previously acquired data in AuAu collisions at the energies √{s_{NN} } = 200, 130, 62.4, and 19.6 GeV and CuCu collisions at √{s_{NN} } = 200, 62.4, and 22.4 GeV. The commencing of a QCD critical point search at RHIC has extended the reach of possible measurements of dynamical K/π and p/π ratio fluctuations from AuAu collisions to lower energies. New results are compared to previous measurements and to theoretical predictions from the UrQMD model.

  11. 2D ERT imaging of tracer dispersion in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Lekmine, G.; Pessel, M.; Auradou, H.

    2009-12-01

    Electrical resistivity tomography applied in cross-borehole is a method often used to follow the invasion process of pollutants. The aim of this work is to test experimentally the electrode arrays and inversion processes used to obtain a spatial representation of tracer propagation in porous media. Experiments were conducted in a plexiglass container with glass beads of 166 microns in diameter. The height of the container is 275 mm, its width 85 mm and its thickness 10 mm. 21 electrodes, equally spaced, are placed along each of the lateral sides of the porous medium : these electrodes are used to perform the electrical measurements. The device is lightened from behind and a video camera records the fluid propagation. The tracer (i.e the pollutant) is a water solution containing a known amount of dye together with NaCl (0.5g/l up to 1.5g/l). The medium is first saturated by a water solution containing a slight concentration of NaCl so that its density is smaller than the tracer’s. An upward flow is first established, the denser fluid is injected at the bottom and over the full width of the medium. In this way, the flow is stabilized by gravity avoiding the development of unstable fingers. Still, the fluids are miscible and a mixing front develops during the flow: in the present study, the interest is to estimate the 2D tracer front dispersion by both optical and electrical imaging. The comparison of the two techniques allows to study the ability of the inversion process to quantify the solute transport. A sensitivity analysis is led in order to determine the best measurement sequence to monitor the tracer’s front evolution through the entire volume of the medium. Hence, each time step is constituted by the same 190 transverse dipole-dipole set of lasting 5 minutes between the first and the last measurement. At the laboratory scale, the experimental design affects the measurements through edges effects: most of these artefacts can be partially suppressed by using

  12. Research and Laboratory Instruction--An Experiment in Teaching

    ERIC Educational Resources Information Center

    Kramm, Kenneth R.

    1976-01-01

    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)

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

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr. (Compiler)

    1990-01-01

    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.

  14. Internal quality assurance in cervical cytology one laboratory's experience.

    PubMed

    Cross, P A

    1996-02-01

    The results of an internal quality assurance exercise in one cervical cytology laboratory in England are presented, using different types of partial percentage re-screening of cervical smears. An overall false negative dyskaryotic rate of up to 4.3% was demonstrated, with the final cytology report diagnosis differing from the primary screening dignosis in 1.3% of cases. These finding are discussed, with the aim of helping to foster debate on the setting of national laboratory internal quality assurance standards.

  15. Effects of experience and electronic stability control on low friction collision avoidance in a truck driving simulator.

    PubMed

    Markkula, Gustav; Benderius, Ola; Wolff, Krister; Wahde, Mattias

    2013-01-01

    Two experiments were carried out in a moving-base simulator, in which truck drivers of varying experience levels encountered a rear-end collision scenario on a low-friction road surface, with and without an electronic stability control (ESC) system. In the first experiment, the drivers experienced one instance of the rear-end scenario unexpectedly, and then several instances of a version of the scenario adapted for repeated collision avoidance. In the second experiment, the unexpected rear-end scenario concluded a stretch of driving otherwise unrelated to the study presented here. Across both experiments, novice drivers were found to collide more often than experienced drivers in the unexpected scenario. This result was found to be attributable mainly to longer steering reaction times of the novice drivers, possibly caused by lower expectancy for steering avoidance. The paradigm for repeated collision avoidance was able to reproduce the type of steering avoidance situation for which critical losses of control were observed in the unexpected scenario and, here, ESC was found to reliably reduce skidding and control loss. However, it remains unclear to what extent the results regarding ESC benefits in repeated avoidance are generalisable to unexpected situations. The approach of collecting data by appending one unexpected scenario to the end of an otherwise unrelated experiment was found useful, albeit with some caveats.

  16. Combining Laboratory Experiments with Digital Tools to Do Scientific Inquiry

    ERIC Educational Resources Information Center

    Kluge, Anders

    2014-01-01

    This qualitative study investigates the gap between a lab experiment and theory of science. Two groups of 4 students in 2 different classes in 11th grade (15-16 years old) are followed as they process results and experiences from a lab experiment using a digital environment. The experiment is as a part of a larger project about genes and cells,…

  17. Lab-scale ash production by abrasion and collision experiments of porous volcanic samples

    NASA Astrophysics Data System (ADS)

    Mueller, Sebastian B.; Lane, Steve J.; Kueppers, Ulrich

    2014-05-01

    In the course of explosive eruptions, magma is fragmented into smaller pieces by a plethora of processes before deposition. Volcanic ash, all fragments smaller than 2 mm, may have imminent and near-volcano effects but may also cause various problems over long duration and/or far away from the source. In an attempt to quantify the efficiency of ash generation, various experimental setups were applied on pumice and scoria samples. We used samples collected on Tenerife (Canary Islands, Spain), Sicily and Lipari Islands (both Italy) for experiments that generated shear or normal stress fields or combinations of these within the rock samples. Experiments were designed to overcome low yield strengths of samples and produce ash, with this study having particular interest in the < 355 µm fraction. By abrasion and collision experiments, the processes that are likely to happen within volcanic conduits, plumes or pyroclastic density currents (PDCs) were simulated. An understanding of these secondary fragmentation processes is crucial as they are capable of producing very fine ash, with size ranges from a few microns to few millimetres. These particles are known to remain in the atmosphere for several days and travel large distances (~ 100s of km). This poses threats to the aviation industry and human health. From the experiments we establish that abrasion setups produced the finest material and up to 50% of the generated ash was smaller than 10 µm. In comparison, the drop experiments that applied mainly normal stress fields produced coarser grain sizes. Results were compared to grain size distributions described in literature for natural fall and PDC deposits and good correlation was found. Energies involved in drop experiments were calculated and showed an exponential correlation with ash production rate. Projecting these results into the actual volcanic environment, highest amounts of ash are produced in most energetic and turbulent areas, which are proximal to the vent

  18. Insights from laboratory experiments into the physics of pyroclastic flows

    NASA Astrophysics Data System (ADS)

    Girolami, L.; Druitt, T. H.; Roche, O.

    2009-12-01

    We studied the transport and sedimentation behavior of rapid shear flows of gas-fluidized volcanic ash in a laboratory flume in order to better understand the kinematics of pyroclastic flows. The work was based on a previous study in which we explored the fluidization and settling behaviour of ash under quasi-static conditions in a 1-D high-temperature fluidization rig. Provided that temperature is high enough (>150 °C) to significantly reduce cohesion, ash fractions of pyroclastic flow deposits fluidize in the manner of Geldart group-A powders, with large expansions in the non-bubbling regime. When the flux of fluidizing gas is removed, the ash re-sediments by hindered settling at rates which, for a given material, are independent of temperature up to 550 °C. Armed with this knowledge, we built a 3-m-long lock-exchange flume in which we generated horizontal flows of fluidized ash. The ash was first placed in the flume reservoir, heated to 180 °C and expanded by gas flow up to 45 % above loose packing. It was then released down the flume and allowed to defluidize freely. The resulting flows were filmed at high speed, and the films were then analyzed visually and using a particle-tracking algorithm. The flows were typically several cm thick, had frontal speeds of up to ~2 m s-1, and were non-turbulent on scales larger than the constituent particles. Since the settling behavior of quasi-static ash is temperature independent, we expect the same to be true for flowing ash. Deposition took place progressively during transport until the flow was entirely consumed and motion ceased. It commenced 5-20 cm rearward of the leading edge and (for a given expansion) proceeded at a rate independent of distance from the lock gate. Deposit aggradation velocities were equal to those inferred beneath quasi-static bed collapse tests of the same ash at the same initial expansions, showing that shear rates of up to ~300 s-1 have no measurable effect on aggradation rate. Initially non

  19. [Brief discussion on experiences from laboratory certification and accreditation on detection of parasitic diseases].

    PubMed

    Xiong, Yan-Hong; Guan, Ya-Yi; Cao, Jian-Ping; Zheng, Bin; Wang, Yan-Juan; Zhang, Min-Qi; Zhou, Xiao-Jun

    2013-12-01

    The laboratory certification and accreditation is the development trend of domestic and international laboratories. The National Institute for Parasitic Diseases, Chinese Center for Disease Control and Prevention passed through the site assessment in September 2012 successfully, 26 items in 8 fields declared were all adopted. This article summarizes some work experiences during carrying out the laboratory certification and accreditation.

  20. Designing Online Resources in Preparation for Authentic Laboratory Experiences

    PubMed Central

    Boulay, Rachel; Parisky, Alex; Leong, Peter

    2013-01-01

    Professional development for science teachers can be benefited through active learning in science laboratories. However, how online training materials can be used to complement traditional laboratory training is less understood. This paper explores the design of online training modules to teach molecular biology and user perception of those modules that were part of an intensive molecular biology “boot camp” targeting high school biology teachers in the State of Hawaii. The John A. Burns School of Medicine at the University of Hawaii had an opportunity to design and develop professional development that prepares science teachers with an introduction of skills, techniques, and applications for their students to conduct medical research in a laboratory setting. A group of 29 experienced teachers shared their opinions of the online materials and reported on how they used the online materials in their learning process or teaching. PMID:24319698

  1. 75 FR 15675 - Professional Research Experience Program in Chemical Science and Technology Laboratory...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... National Institute of Standards and Technology Professional Research Experience Program in Chemical Science...) Chemical Science and Technology Laboratory (CSTL) announces that the Professional Research Experience... Research and Standards--11.609. Program Description: The National Institute of Standards and...

  2. Stochastic collision and aggregation analysis of kaolinite in water through experiments and the spheropolygon theory.

    PubMed

    Tang, Fiona H M; Alonso-Marroquin, Fernando; Maggi, Federico

    2014-04-15

    An approach based on spheropolygons (i.e., the Minkowski sum of a polygon with N vertices and a disk with spheroradius r) is presented to describe the shape of kaolinite aggregates in water and to investigate interparticle collision dynamics. Spheropolygons generated against images of kaolinite aggregates achieved an error between 0.5% and 20% as compared to at least 32% of equivalent spheres. These spheropolygons were used to investigate the probability of collision (Pr[C]) and aggregation (Pr[A]) under the action of gravitational, viscous, contact (visco-elastic), electrostatic and van der Waals forces. In ortho-axial (i.e., frontal) collision, Pr[A] of equivalent spheres was always 1, however, stochastic analysis of collision among spheropolygons showed that Pr[A] decreased asymptotically with N increasing, and decreased further in peri-axial (i.e., tangential) collision. Trajectory analysis showed that not all collisions occurring within the attraction zone of the double layer resulted in aggregation, neither all those occurring outside it led to relative departure. Rather, the relative motion on surface asperities affected the intensity of contact and attractive forces to an extent to substantially control a collision outcome in either instances. Spheropolygons revealed therefore how external shape can influence particle aggregation, and suggested that this is equally important to contact and double layer forces in determining the probability of particle aggregation.

  3. Laboratory experiments for defining scaling relations between rock material properties and rock resistance to erosion

    NASA Astrophysics Data System (ADS)

    Sklar, L. S.; Beyeler, J. D.; Collins, G. C.; Farrow, J. W.; Hsu, L.; Litwin, K. L.; Polito, P. J.

    2012-12-01

    Rock resistance to erosion is a key variable that limits rates of morphologic change and mass flux in landscapes. However, we have limited knowledge of how measurable material properties influence rock resistance to specific erosion processes. Rock 'erodibility' is commonly a free parameter in surface process models, where users assign or solve for numerical values that lack meaning outside of the model. Moreover, erodibility parameters often lump material resistance to erosion together with aspects of the forces driving erosion that are not explicitly represented in the model. Laboratory experiments in which rock types are varied, while erosive forces are held constant, can be used to develop scaling relationships between rock properties and erosion resistance for individual detachment mechanisms. With knowledge of why erosion rates vary between rock types for constant erosive forces, laboratory and field experiments that vary erosive intensity can be used to quantify the absolute susceptibility to erosion in physically explicit terms. Here we synthesize data collected over the past decade from a suite of laboratory investigations of rock resistance to wear by sediment particle impacts, and wear of sediment particles themselves, in experiments replicating fluvial and granular flow conditions. Materials tested included: field-sampled bedrock and sediment covering the widest feasible range of apparent durability and lithologic type; synthetic sandstones made from mixtures of sand and Portland cement; and water ice, both pure and containing solid impurities, tested over a wide range of temperatures. Material properties measured included: dry-bulk and saturated density, porosity, tensile strength, fracture toughness, elastic moduli, mineralogy, cement type, and the grain size of mineral crystals and cemented clasts. Erosion rates were measured by mass or volume loss divided by run time, in bedrock abrasion mills, barrel tumblers, and a large rotating drum. We find

  4. Some More Simple Laser Experiments for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Yap, F. Y.

    1969-01-01

    Describes three elementary optics experiments using a laser instead of conventional light sources. Experiments illustrate the Fresnel-Arago law, elliptical polarization, double refraction and polarization in calcite, and interference by a Fresnel biprism. Because of the high intensity of the laser beam, these experiments lend themselves very well…

  5. Raising Environmental Awareness through Applied Biochemistry Laboratory Experiments

    ERIC Educational Resources Information Center

    Salman Ashraf, S.

    2013-01-01

    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…

  6. Integrating Interdisciplinary Research-Based Experiences in Biotechnology Laboratories

    ERIC Educational Resources Information Center

    Iyer, Rupa S.; Wales, Melinda E.

    2012-01-01

    The increasingly interdisciplinary nature of today's scientific research is leading to the transformation of undergraduate education. In addressing these needs, the University of Houston's College of Technology has developed a new interdisciplinary research-based biotechnology laboratory curriculum. Using the pesticide degrading bacterium,…

  7. 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...

  8. The Nature of Laboratory Learning Experiences in Secondary Science Online

    ERIC Educational Resources Information Center

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

    2013-01-01

    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…

  9. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, Andri L.; Tan, Paula

    2006-01-01

    Students in introductory chemistry classes typically appreciate seeing the connection between course content and the "real world". For this reason, we have developed a synthesis of creatine monohydrate--a popular supplement used in sports requiring short bursts of energy--for introductory organic chemistry laboratory courses. Creatine monohydrate…

  10. A Virtual Laboratory on Natural Computing: A Learning Experiment

    ERIC Educational Resources Information Center

    de Castro, Leandro Nunes; Muñoz, Yupanqui Julho; de Freitas, Leandro Rubim; El-Hani, Charbel Niño

    2008-01-01

    Natural computing is a terminology used to describe computational algorithms developed by taking inspiration from information processing mechanisms in nature, methods to synthesize natural phenomena in computers, and novel computational approaches based on natural materials. The virtual laboratory on natural computing (LVCoN) is a Web environment…

  11. Students' Experience in a General Chemistry Cooperative Problem Based Laboratory

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  12. Restructuring a General Microbiology Laboratory into an Investigative Experience.

    ERIC Educational Resources Information Center

    Deutch, Charles E.

    1994-01-01

    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)

  13. Laboratory Experiences in an Introduction to Natural Science Course.

    ERIC Educational Resources Information Center

    Barnard, Sister Marquita

    1984-01-01

    Describes a two-semester course designed to meet the needs of future elementary teachers, home economists, and occupational therapists. Laboratory work includes homemade calorimeters, inclined planes, and computing. Content areas of the course include measurement, physics, chemistry, astronomy, biology, geology, and meteorology. (JN)

  14. Simulated and Virtual Science Laboratory Experiments: Improving Critical Thinking and Higher-Order Learning Skills

    ERIC Educational Resources Information Center

    Simon, Nicole A.

    2013-01-01

    Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory…

  15. Parallel Combinatorial Synthesis of Azo Dyes: A Combinatorial Experiment Suitable for Undergraduate Laboratories

    ERIC Educational Resources Information Center

    Gung, Benjamin W.; Taylor, Richard T.

    2004-01-01

    An experiment in the parallel synthesis of azo dyes that demonstrates the concepts of structure-activity relationships and chemical diversity with vivid colors is described. It is seen that this experiment is suitable for the second-semester organic chemistry laboratory and also for the one-semester organic laboratory.

  16. Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students

    ERIC Educational Resources Information Center

    Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

    2011-01-01

    This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

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

    ERIC Educational Resources Information Center

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

    2014-01-01

    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…

  18. An Example of a Laboratory Teaching Experience in a Professional Year (Plan B) Program

    ERIC Educational Resources Information Center

    Miller, P. J.; And Others

    1978-01-01

    A laboratory teaching experience (L.T.E.) was designed to focus on three teaching behaviors. It was recognized that a behavioral approach to teaching simplified its complexity by isolating specific teaching behaviors. Discusses the development and evaluation of the laboratory teaching experience. (Author/RK)

  19. A Laboratory Experiment for Rapid Determination of the Stability of Vitamin C

    ERIC Educational Resources Information Center

    Adem, Seid M.; Lueng, Sam H.; Elles, Lisa M. Sharpe; Shaver, Lee Alan

    2016-01-01

    Experiments in laboratory manuals intended for general, organic, and biological (GOB) chemistry laboratories include few opportunities for students to engage in instrumental methods of analysis. Many of these students seek careers in modern health-related fields where experience in spectroscopic techniques would be beneficial. A simple, rapid,…

  20. Capillary Electrophoresis Analysis of Cations in Water Samples: An Experiment for the Introductory Laboratory

    ERIC Educational Resources Information Center

    Pursell, Christopher J.; Chandler, Bert; Bushey, Michelle M.

    2004-01-01

    Capillary electrophoresis is gradually working its way into the undergraduate laboratory curriculum. Typically, experiments utilizing this newer technology have been introduced into analytical or instrumental courses. The authors of this article have introduced an experiment into the introductory laboratory that utilizes capillary electrophoresis…

  1. An Undergraduate Laboratory Experiment in Bioinorganic Chemistry: Ligation States of Myoglobin

    ERIC Educational Resources Information Center

    Bailey, James A.

    2011-01-01

    Although there are numerous inorganic model systems that are readily presented as undergraduate laboratory experiments in bioinorganic chemistry, there are few examples that explore the inorganic chemistry of actual biological molecules. We present a laboratory experiment using the oxygen-binding protein myoglobin that can be easily incorporated…

  2. Concepts for unique laboratory astrophysics experiments on NIF

    NASA Astrophysics Data System (ADS)

    Remington, Bruce

    2008-11-01

    The ability to experimentally study scaled aspects of the explosion dynamics of core- collapse supernovae (massive stars that explode from the inside out) or the radiation kinetics of accreting neutron stars or black holes on high energy density (HED) facilities, such as the new National Ignition Facility (NIF), is an exciting scientific development. [``Experimental astrophysics with high power lasers and Z pinches,'' B.A. Remington, R.P. Drake, D.D. Ryutov, Rev. Mod. Phys. 78, 755 (2006)] Additional areas of research that could become accessible on NIF are studies of fundamental properties of matter in conditions relevant to the cores giant planets and stars, protostellar jet dynamics, radiatively driven molecular cloud dynamics, hyper-velocity (10-100 km/s) dust-dust collisions, and combined with ultraintense short-pulse lasers, pair plasma generation and dynamics, possibly relevant to gamma-ray burst physics. With the added tool of thermonuclear ignition on the National Ignition Facility, excited state (``multi-hit'') nuclear physics studies, and burn physics studies also become possible. Techniques and methodologies for studying aspects of the physics of such extreme phenomena of the universe in submillimeter scale parcels of matter on NIF will be discussed.

  3. Social setting, intuition and experience in laboratory experiments interact to shape cooperative decision-making.

    PubMed

    Capraro, Valerio; Cococcioni, Giorgia

    2015-07-22

    Recent studies suggest that cooperative decision-making in one-shot interactions is a history-dependent dynamic process: promoting intuition versus deliberation typically has a positive effect on cooperation (dynamism) among people living in a cooperative setting and with no previous experience in economic games on cooperation (history dependence). Here, we report on a laboratory experiment exploring how these findings transfer to a non-cooperative setting. We find two major results: (i) promoting intuition versus deliberation has no effect on cooperative behaviour among inexperienced subjects living in a non-cooperative setting; (ii) experienced subjects cooperate more than inexperienced subjects, but only under time pressure. These results suggest that cooperation is a learning process, rather than an instinctive impulse or a self-controlled choice, and that experience operates primarily via the channel of intuition. Our findings shed further light on the cognitive basis of human cooperative decision-making and provide further support for the recently proposed social heuristics hypothesis.

  4. Results (and future prospects) of the CMS experiment in photon-induced interactions in p-Pb collisions

    NASA Astrophysics Data System (ADS)

    Bylinkin, Alexander

    2017-03-01

    Exclusive vector meson photoproduction is studied in ultra-peripheral pPb collisions at √{sN N }=5.02 TeV with the CMS experiment at the LHC. The cross sections are measured as a function of the photon-proton centre-of-mass energy, extending the energy range explored by H1 and ZEUS Experiments at HERA. In addition, the differential cross sections (dσ/d|t|), where | t | ≈pT2 is the squared transverse momentum of produced vector mesons, are measured and the slope parameters are obtained. The results are compared to previous measurements and to theoretical predictions. Finally, prospect for further measurements of vector meson production that can be performed using the 2016 pPb collision data at 8 TeV to be collected at the end of the year are presented.

  5. Constraint on Nuclear Symmetry Energy through Heavy RI Collision Experiment by Using SπRIT Device at RIBF-SAMURAI

    NASA Astrophysics Data System (ADS)

    Isobe, Tadaaki

    The symmetry energy of the nuclear Equation of State (EoS) is essential in many aspects of the astrophysics. However it has large ambiguity mainly for the dense region of ρ > ρ0. In order to give a constraint on the dencity dependent nuclear symmetry energy, an international experimental project at RIKEN-RIBF: SπRIT was launched. By using newly developed Time Projection Chamber (TPC) as a main device of SπRIT experiment, first heavy RI collision experiment was performed in the spring of 2016. In this experiment, charged π meson was measured as main observable as it is expected to be most sensitive to the symmetry energy.

  6. From laboratory plasma experiments to space plasma experiments with `CubeSat' nano-satellites

    NASA Astrophysics Data System (ADS)

    Charles, Christine

    2016-09-01

    `CubeSat' nano-satellites provide low-cost access to space. SP3 laboratory's involvement in the European Union `QB50' `CubeSat' project [www.qb50.eu] which will launch into space 50 `CubeSats' from 27 Countries to study the ionosphere and the lower thermosphere will be presented. The Chi Kung laboratory plasma experiment and the Helicon Double Layer Thruster prototype can be tailored to investigate expanding magnetized plasma physics relevant to space physics (solar corona, Earth's aurora, adiabatic expansion and polytropic studies). Chi Kung is also used as a plasma wind tunnel for ground-based calibration of the University College London QB50 Ion Neutral Mass Spectrometer. Space qualification of the three Australian QB50 `CubeSats' (June 2016) is carried out in the WOMBAT XL space simulation chamber. The QB50 satellites have attitude control but altitude control is not a requirement. SP3 is developing end-to-end miniaturised radiofrequency plasma propulsion systems (such as the Pocket Rocket and the MiniHel thrusters with power and propellant sub-systems) for future `CubeSat' missions.

  7. Touring the Tomato: A Suite of Chemistry Laboratory Experiments

    PubMed Central

    Sarkar, Sayantani; Chatterjee, Subhasish; Medina, Nancy; Stark, Ruth E.

    2013-01-01

    An eight-session interdisciplinary laboratory curriculum has been designed using a suite of analytical chemistry techniques to study biomaterials derived from an inexpensive source such as the tomato fruit. A logical progression of research-inspired laboratory modules serves to “tour” the macroscopic characteristics of the fruit and the submicroscopic properties of its constituent cuticular biopolymers by atomic force microscopy (AFM), UV–visible, and nuclear magnetic resonance (NMR) methods at increasingly detailed molecular levels. The modular curriculum can be tailored for specialty undergraduate courses or summer high school workshops. By applying analytical tools to investigate biopolymers, making connections between molecular and microscale structure, and linking both structural regimes to the functional properties of natural polymers, groundwork is established for further student investigations at the interface of chemistry with biology or chemical engineering. PMID:23526490

  8. Touring the Tomato: A Suite of Chemistry Laboratory Experiments.

    PubMed

    Sarkar, Sayantani; Chatterjee, Subhasish; Medina, Nancy; Stark, Ruth E

    2013-03-12

    An eight-session interdisciplinary laboratory curriculum has been designed using a suite of analytical chemistry techniques to study biomaterials derived from an inexpensive source such as the tomato fruit. A logical progression of research-inspired laboratory modules serves to "tour" the macroscopic characteristics of the fruit and the submicroscopic properties of its constituent cuticular biopolymers by atomic force microscopy (AFM), UV-visible, and nuclear magnetic resonance (NMR) methods at increasingly detailed molecular levels. The modular curriculum can be tailored for specialty undergraduate courses or summer high school workshops. By applying analytical tools to investigate biopolymers, making connections between molecular and microscale structure, and linking both structural regimes to the functional properties of natural polymers, groundwork is established for further student investigations at the interface of chemistry with biology or chemical engineering.

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

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    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.

  10. A "Greenhouse Gas" Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

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

    2014-01-01

    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…

  11. A Thin Layer Chromatography Laboratory Experiment of Medical Importance

    ERIC Educational Resources Information Center

    Sharma, Loretta; Desai, Ankur; Sharma, Ajit

    2006-01-01

    A thin layer chromatography experiment of medical importance is described. The experiment involves extraction of lipids from simulated amniotic fluid samples followed by separation, detection, and scanning of the lecithin and sphingomyelin bands on TLC plates. The lecithin-to-sphingomyelin ratio is calculated. The clinical significance of this…

  12. A Spectroscopic-Based Laboratory Experiment for Protein Conformational Studies

    ERIC Educational Resources Information Center

    Ramos, Carlos Henrique I.

    2004-01-01

    This article describes a practical experiment for teaching basic spectroscopic techniques to introduce the topic of protein conformational change to students in the field of molecular biology, biochemistry, or structural biology. The spectroscopic methods employed in the experiment are absorbance, for protein concentration measurements, and…

  13. A Cyclic Voltammetry Experiment for the Instrumental Analysis Laboratory.

    ERIC Educational Resources Information Center

    Baldwin, Richard P.; And Others

    1984-01-01

    Background information and procedures are provided for experiments that illustrate the nature of cyclic voltammetry and its application in the characterization of organic electrode processes. The experiments also demonstrate the concepts of electrochemical reversibility and diffusion-controlled mass transfer. (JN)

  14. Reactions of Thiocyanate Ions with Acid: A Laboratory Experiment.

    ERIC Educational Resources Information Center

    Glidewell, Christopher; And Others

    1984-01-01

    Background information, procedures, and typical results are provided for a three-part experiment involving reactions of potassium thiocynate (KNCS) with sulfuric acid. The experiment represents the final stage of structured work prior to students' research projects during their final year. (JM)

  15. Microcomputer-Based Digital Signal Processing Laboratory Experiments.

    ERIC Educational Resources Information Center

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

    1985-01-01

    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)

  16. A Membrane Gas Separation Experiment for the Undergraduate Laboratory.

    ERIC Educational Resources Information Center

    Davis, Richard A.; Sandall, Orville C.

    1991-01-01

    Described is a membrane experiment that provides students with experience in fundamental engineering skills such as mass balances, modeling, and using the computer as a research tool. Included are the experimental design, theory, method of solution, sample calculations, and conclusions. (KR)

  17. A Semi-Batch Reactor Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Derevjanik, Mario; Badri, Solmaz; Barat, Robert

    2011-01-01

    This experiment and analysis offer an economic yet challenging semi-batch reactor experience. Household bleach is pumped at a controlled rate into a batch reactor containing pharmaceutical hydrogen peroxide solution. Batch temperature, product molecular oxygen, and the overall change in solution conductivity are metered. The reactor simulation…

  18. The RC Circuit--A Multipurpose Laboratory Experiment.

    ERIC Educational Resources Information Center

    Wood, Herbert T.

    1993-01-01

    Describes an experiment that demonstrates the use of Kirchoff's rules in the analysis of electrical circuits. The experiment also involves the solution of a linear nonhomogeneous differential equation that is slightly different from the standard one for the simple RC circuit. (ZWH)

  19. Undergraduate Laboratory Experiment Modules for Probing Gold Nanoparticle Interfacial Phenomena

    ERIC Educational Resources Information Center

    Karunanayake, Akila G.; Gunatilake, Sameera R.; Ameer, Fathima S.; Gadogbe, Manuel; Smith, Laura; Mlsna, Deb; Zhang, Dongmao

    2015-01-01

    Three gold-nanoparticle (AuNP) undergraduate experiment modules that are focused on nanoparticles interfacial phenomena have been developed. Modules 1 and 2 explore the synthesis and characterization of AuNPs of different sizes but with the same total gold mass. These experiments enable students to determine how particle size affects the AuNP…

  20. Iron-Sulfur-Carbonyl and -Nitrosyl Complexes: A Laboratory Experiment.

    ERIC Educational Resources Information Center

    Glidewell, Christopher; And Others

    1985-01-01

    Background information, materials needed, procedures used, and typical results obtained, are provided for an experiment on iron-sulfur-carbonyl and -nitrosyl complexes. The experiment involved (1) use of inert atmospheric techniques and thin-layer and flexible-column chromatography and (2) interpretation of infrared, hydrogen and carbon-13 nuclear…

  1. Laser-driven ICF experiments: Laboratory Report No. 223

    SciTech Connect

    McCrory, R.L.

    1991-04-01

    Laser irradiation uniformity is a key issue and is treated in some detail. The basic irradiation uniformity requirements and practical ways of achieving these requirements are both discussed, along with two beam-smoothing techniques: induced spatial incoherence (ISI), and smoothing by spectral dispersion (SSD). Experiments to measure and control the irradiation uniformity are also highlighted. Following the discussion of irradiation uniformity, a brief review of coronal physics is given, including the basic physical processes and their experimental signatures, together with a summary of pertinent diagnostics and results from experiments. Methods of determining ablation rates and thermal transport are also described. The hydrodynamics of laser-driven targets must be fully understood on the basis of experiments. Results from implosion experiments, including a brief description of the diagnostics, are presented. Future experiments aimed at determining ignition scaling and demonstrating hydrodynamically equivalent physics applicable to high-gain designs.

  2. Three-pion Hanbury Brown-Twiss correlations in relativistic heavy-ion collisions from the STAR experiment.

    PubMed

    Adams, J; Adler, C; Ahammed, Z; Allgower, C; Amonett, J; Anderson, B D; Anderson, M; Arkhipkin, D; Averichev, G S; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellwied, R; Berger, J; Bichsel, H; Billmeier, A; Bland, L C; Blyth, C O; Bonner, B E; Botje, M; Boucham, A; Brandin, A; Bravar, A; Cadman, R V; Cai, X Z; Caines, H; Calderón de la Barca Sánchez, M; Cardenas, A; Carroll, J; Castillo, J; Castro, M; Cebra, D; Chaloupka, P; Chattopadhyay, S; Chen, Y; Chernenko, S P; Cherney, M; Chikanian, A; Choi, B; Christie, W; Coffin, J P; Cormier, T M; Mora Corral, M; Cramer, J G; Crawford, H J; Derevschikov, A A; Didenko, L; Dietel, T; Draper, J E; Dunin, V B; Dunlop, J C; Eckardt, V; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Fachini, P; Faine, V; Faivre, J; Fatemi, R; Filimonov, K; Finch, E; Fisyak, Y; Flierl, D; Foley, K J; Fu, J; Gagliardi, C A; Gagunashvili, N; Gans, J; Gaudichet, L; Germain, M; Geurts, F; Ghazikhanian, V; Grachov, O; Guedon, M; Guertin, S M; Gushin, E; Gutierrez, T D; Hallman, T J; Hardtke, D; Harris, J W; Heinz, M; Henry, T W; Heppelmann, S; Herston, T; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horsley, M; Huang, H Z; Humanic, T J; Igo, G; Ishihara, A; Jacobs, P; Jacobs, W W; Janik, M; Johnson, I; Jones, P G; Judd, E G; Kabana, S; Kaneta, M; Kaplan, M; Keane, D; Kiryluk, J; Kisiel, A; Klay, J; Klein, S R; Klyachko, A; Kollegger, T; Konstantinov, A S; Kopytine, M; Kotchenda, L; Kovalenko, A D; Kramer, M; Kravtsov, P; Krueger, K; Kuhn, C; Kulikov, A I; Kunde, G J; Kunz, C L; Kutuev, R Kh; Kuznetsov, A A; Lamont, M A C; Landgraf, J M; Lange, S; Lansdell, C P; Lasiuk, B; Laue, F; Lauret, J; Lebedev, A; Lednický, R; Leontiev, V M; LeVine, M J; Li, Q; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, L; Liu, Z; Liu, Q J; Ljubicic, T; Llope, W J; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Ludlam, T; Lynn, D; Ma, J; Ma, Y G; Magestro, D; Majka, R; Margetis, S; Markert, C; Martin, L; Marx, J; Matis, H S; Matulenko, Yu A; McShane, T S; Meissner, F; Melnick, Yu; Meschanin, A; Messer, M; Miller, M L; Milosevich, Z; Minaev, N G; Mitchell, J; Molnar, L; Moore, C F; Morozov, V; de Moura, M M; Munhoz, M G; Nelson, J M; Nevski, P; Nikitin, V A; Nogach, L V; Norman, B; Nurushev, S B; Odyniec, G; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Paic, G; Pandey, S U; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Perevoztchikov, V; Peryt, W; Petrov, V A; Picha, R; Planinic, M; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potrebenikova, E; Prindle, D; Pruneau, C; Putschke, J; Rai, G; Rakness, G; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J G; Renault, G; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Rose, A; Roy, C; Rykov, V; Sakrejda, I; Salur, S; Sandweiss, J; Savin, I; Schambach, J; Scharenberg, R P; Schmitz, N; Schroeder, L S; Schweda, K; Seger, J; Seyboth, P; Shahaliev, E; Shestermanov, K E; Shimanskii, S S; Simon, F; Skoro, G; Smirnov, N; Snellings, R; Sorensen, P; Sowinski, J; Spinka, H M; Srivastava, B; Stephenson, E J; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Struck, C; Suaide, A A P; Sugarbaker, E; Suire, C; Sumbera, M; Surrow, B; Symons, T J M; Szanto de Toledo, A; Szarwas, P; Tai, A; Takahashi, J; Tang, A H; Thein, D; Thomas, J H; Thompson, M; Timoshenko, S; Tokarev, M; Tonjes, M B; Trainor, T A; Trentalange, S; Tribble, R E; Trofimov, V; Tsai, O; Ullrich, T; Underwood, D G; Van Buren, G; Vander Molen, A M; Vasiliev, A N; Vigdor, S E; Voloshin, S A; Vznuzdaev, M; Wang, F; Wang, Y; Ward, H; Watson, J W; Wells, R; Westfall, G D; Whitten, C; Wieman, H; Willson, R; Wissink, S W; Witt, R; Wood, J; Xu, N; Xu, Z; Yakutin, A E; Yamamoto, E; Yang, J; Yepes, P; Yurevich, V I; Zanevski, Y V; Zborovský, I; Zhang, H; Zhang, W M; Zoulkarneev, R; Zoulkarneeva, J; Zubarev, A N

    2003-12-31

    Data from the first physics run at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory, Au+Au collisions at sqrt[s(NN)]=130 GeV, have been analyzed by the STAR Collaboration using three-pion correlations with charged pions to study whether pions are emitted independently at freeze-out. We have made a high-statistics measurement of the three-pion correlation function and calculated the normalized three-particle correlator to obtain a quantitative measurement of the degree of chaoticity of the pion source. It is found that the degree of chaoticity seems to increase with increasing particle multiplicity.

  3. Isospin Effects in Heavy-Ion Collisions: Some Results From CHIMERA Experiments At LNS And Perspectives With Radioactive Beams

    SciTech Connect

    Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Verde, G.; Amorini, F.; Cavallaro, S.; Lombardo, I.; Porto, F.; Rizzo, F.; Russotto, P.; Anzalone, A.; Maiolino, C.; Arena, N.; Geraci, E.; Grassi, L.; Lo Nigro, S.; Politi, G.; Auditore, L.

    2009-05-04

    CHIMERA is a 4{pi} multidetector for charged particles available at Laboratori Nazionali del Sud (INFN-LNS). A new method to measure the time scale of the emission of nuclear fragments is described, together with some applications in the field of the isospin dynamics of heavy-ion collisions. Competition between fusion-like and binary reactions near the energy threshold for nuclear multifragmentation is discussed. Opportunities are pointed out to use the detector at low and intermediate energies using the kinematical-coincidence method.

  4. A teaching intervention for reading laboratory experiments in college-level introductory chemistry

    NASA Astrophysics Data System (ADS)

    Kirk, Maria Kristine

    The purpose of this study was to determine the effects that a pre-laboratory guide, conceptualized as a "scientific story grammar," has on college chemistry students' learning when they read an introductory chemistry laboratory manual and perform the experiments in the chemistry laboratory. The participants (N = 56) were students enrolled in four existing general chemistry laboratory sections taught by two instructors at a women's liberal arts college. The pre-laboratory guide consisted of eight questions about the experiment, including the purpose, chemical species, variables, chemical method, procedure, and hypothesis. The effects of the intervention were compared with those of the traditional pre-laboratory assignment for the eight chemistry experiments. Measures included quizzes, tests, chemistry achievement test, science process skills test, laboratory reports, laboratory average, and semester grade. The covariates were mathematical aptitude and prior knowledge of chemistry and science processes, on which the groups differed significantly. The study captured students' perceptions of their experience in general chemistry through a survey and interviews with eight students. The only significant differences in the treatment group's performance were in some subscores on lecture items and laboratory items on the quizzes. An apparent induction period was noted, in that significant measures occurred in mid-semester. Voluntary study with the pre-laboratory guide by control students precluded significant differences on measures given later in the semester. The groups' responses to the survey were similar. Significant instructor effects on three survey items were corroborated by the interviews. The researcher's students were more positive about their pre-laboratory tasks, enjoyed the laboratory sessions more, and were more confident about doing chemistry experiments than the laboratory instructor's groups due to differences in scaffolding by the instructors.

  5. Laboratory experiments duplicate conditions in the Earth’s crust

    USGS Publications Warehouse

    Peselnick, L.; Dieterich, J.H.; Stewart, R.M.

    1974-01-01

    An experimental device that simulates conditions in the Earth's crust at depths of up to 30 kilometers has been constructed by geophysicists working at the U.S Geological Survey laboratories in Menlo Park, California. A high pressure "bomb" is being used to experimentally measure the velocity of seismic waves in different types of rock at various confining pressures and temperatures. The principal purpose of these measurements is to determine the elastic and non-elastic properties of rocks and minerals under conditions of high-pressure such as exist deep in the Earth's crust. 

  6. Absorption spectroscopy of a laboratory photoionized plasma experiment at Z

    SciTech Connect

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

    2014-03-15

    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.

  7. Laboratory experiments of relevance to the space station environment

    NASA Technical Reports Server (NTRS)

    Caledonia, G. E.

    1988-01-01

    It has been found that the interaction between orbital vehicles and the ambient environment produces a contaminant cloud which can cause deletrious effects to spacecraft materials and equipment, create increased radiative backgrounds that would interfere with observational instrumentation, and enhance surface charging. A brief overview of the phenomena that produce the contaminant cloud is presented along with a review of physical data required to characterize it. Laboratory techniques which can be utilized to provide the required data are described. In particular, several oxygen beam apparati are discussed.

  8. Zero-gravity atmospheric Cloud Physics Experiment Laboratory; Programmatics report

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The programmatics effort included comprehensive analyses in four major areas: (1) work breakdown structure, (2) schedules, (3) costs, and (4) supporting research and technology. These analyses are discussed in detail in the following sections which identify and define the laboratory project development schedule, cost estimates, funding distributions and supporting research and technology requirements. All programmatics analyses are correlated among themselves and with the technical analyses by means of the work breakdown structure which serves as a common framework for program definition. In addition, the programmatic analyses reflect the results of analyses and plans for reliability, safety, test, and maintenance and refurbishment.

  9. Laboratory dust experiments - Tracing the composition of cometary dust

    NASA Technical Reports Server (NTRS)

    Greenberg, J. M.

    1983-01-01

    The structure and composition of the comet nucleus are investigated theoretically on the basis of aggregation models and laboratory simulations of interstellar-grain evolution. The results are presented in graphs, diagrams, and drawings and discussed in detail. The nucleus is described as a loose tangle of rodlike grains containing about 28 percent H2O, 10 percent CO2 and CO, and 33 percent nonvolatile submicron-size grit particles (silicates, complex organics, and carbon). Evidence from meteorites suggests that the C-12/C-13 ratio of the volatile components is greater than 100.

  10. 4,5-Diphenyl-1-methylimidazole: An Undergraduate Laboratory Experiment.

    ERIC Educational Resources Information Center

    Anastas, Paul T.; And Others

    1985-01-01

    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)

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

    ERIC Educational Resources Information Center

    Touvelle, Michele; Venugopalan, Mundiyath

    1986-01-01

    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)

  12. The Semipermeability of Biological Membranes: An Undergraduate Laboratory Experiment.

    ERIC Educational Resources Information Center

    Frimer, Aryeh A.

    1985-01-01

    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)

  13. Combining Laboratory Experiments with Digital Tools to Do Scientific Inquiry

    NASA Astrophysics Data System (ADS)

    Kluge, Anders

    2014-09-01

    This qualitative study investigates the gap between a lab experiment and theory of science. Two groups of 4 students in 2 different classes in 11th grade (15-16 years old) are followed as they process results and experiences from a lab experiment using a digital environment. The experiment is as a part of a larger project about genes and cells, and this study concerns how the digital environment can support students' sensemaking. The study shows how the students only are left with 'how-to' skills before they engage in collaborative processing supported by their own picture from the experiment. The picture becomes a hub for interactive sensemaking and is extensively used for annotation and discussion. Four elements in the digital support are identified as crucial: an extendable point of reference, facilitation to compare and contrast, a pointer to standard science knowledge, and a structure to guide the students to significant issues. The study identifies where the digital support succeeds and fails in this process of sensemaking from a lab experiment.

  14. From laboratory to industry Phasics experience (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wattellier, Benoit F.; Lebrun, Marie-Begoña.

    2016-03-01

    We describe several examples of technology transfer from academic laboratories to PHASICS. PHASICS was created in 2003 as a spin-off of LULI an academic laboratory working on plasma physics and developing high power lasers to create such objects which temperature and pressure conditions are close to those at the center of stars. In order to optimize the intensity at laser focus, several thesis treated the subject of adaptive optics for lasers. LULI decided to collaborate with ONERA who just invented a technique for wave front sensing called multiwave lateral shearing interferometry. Though developed at first for infrared metrology applications, this technique proved to be very efficient with lasers because it was able to analyze wave front of modulated beams with sharp edges. Before being industrialized the technique was further improved to a compact version called quadriwave lateral shearing interferometry. As soon as PHASICS was created, we felt the potential of making wave front images from transparent objects because of QWLSI high spatial resolution. PHASICS and Institut Fresnel started a collaboration to study applications in microscopy imaging. Research subjects include biological imaging, CARS microscopy, anisotropy imaging, or laser damage testing. The results of research were then included in PHASICS products but sometimes only a tool developed during the project became a product. We will present research works that led to transfers as well as the method we used to ensure fruitful collaboration and transfer.

  15. Chemistry Graduate Teaching Assistants' Experiences in Academic Laboratories and Development of a Teaching Self-image

    NASA Astrophysics Data System (ADS)

    Gatlin, Todd Adam

    Graduate teaching assistants (GTAs) play a prominent role in chemistry laboratory instruction at research based universities. They teach almost all undergraduate chemistry laboratory courses. However, their role in laboratory instruction has often been overlooked in educational research. Interest in chemistry GTAs has been placed on training and their perceived expectations, but less attention has been paid to their experiences or their potential benefits from teaching. This work was designed to investigate GTAs' experiences in and benefits from laboratory instructional environments. This dissertation includes three related studies on GTAs' experiences teaching in general chemistry laboratories. Qualitative methods were used for each study. First, phenomenological analysis was used to explore GTAs' experiences in an expository laboratory program. Post-teaching interviews were the primary data source. GTAs experiences were described in three dimensions: doing, knowing, and transferring. Gains available to GTAs revolved around general teaching skills. However, no gains specifically related to scientific development were found in this laboratory format. Case-study methods were used to explore and illustrate ways GTAs develop a GTA self-image---the way they see themselves as instructors. Two general chemistry laboratory programs that represent two very different instructional frameworks were chosen for the context of this study. The first program used a cooperative project-based approach. The second program used weekly, verification-type activities. End of the semester interviews were collected and served as the primary data source. A follow-up case study of a new cohort of GTAs in the cooperative problem-based laboratory was undertaken to investigate changes in GTAs' self-images over the course of one semester. Pre-semester and post-semester interviews served as the primary data source. Findings suggest that GTAs' construction of their self-image is shaped through the

  16. Laboratory Experiments on the Control of Cyclops Transmitting Guinea Worm

    PubMed Central

    Muller, Ralph

    1970-01-01

    Infection with the guinea worm (Dracunculus medinensis) affects millions of people living in rural areas in certain parts of the world. Usually, the standard of living is low and elaborate control measures would not be feasible. In this study, various insecticidal and molluscicidal compounds were tested in the laboratory for their toxicity to the intermediate hosts, namely, various species of cyclops, which often live in sources of potable water, such as step-wells, cisterns and ponds. Cheapness, low toxicity to mammals and ease of application, in conjunction with effectiveness against cyclops, are primary requisites for any compound accepted for widespread use. Abate, an insecticide, has been shown to be particularly promising in these respects. The timing and mode of application of compounds toxic to cyclops in various endemic regions are discussed. PMID:4247122

  17. Radiative Transfer Theory Verified by Controlled Laboratory Experiments

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

    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.

  18. A Process Dynamics and Control Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Spencer, Jordan L.

    2009-01-01

    This paper describes a process control experiment. The apparatus includes a three-vessel glass flow system with a variable flow configuration, means for feeding dye solution controlled by a stepper-motor driven valve, and a flow spectrophotometer. Students use impulse response data and nonlinear regression to estimate three parameters of a model…

  19. A Laboratory Experiment on How to Create Dimensionless Correlations

    ERIC Educational Resources Information Center

    Edwards, Robert V.

    2010-01-01

    An experiment is described that illustrates how chemical engineering correlations are created. Balls of different diameters and different specific gravities (all less than one) are dropped from several heights into a pool of water, and the maximum depth reached by the ball is measured. This data is used to estimate the coefficients for a…

  20. Laboratory Experiences for Disadvantaged Youth in the Middle School.

    ERIC Educational Resources Information Center

    Baillie, John H.

    This guide contains experiments in the fields of Physical Science, Earth Science, and Biological Science designed to be used with any series of texts in a sequence for disadvantaged youth in the middle school. Any standard classroom can be used, with minor modifications and inexpensive equipment and materials. All students could participate,…

  1. Car-Crash Experiment for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Ball, Penny L.; And Others

    1974-01-01

    Describes an interesting, inexpensive, and highly motivating experiment to study uniform and accelerated motion by measuring the position of a car as it crashes into a rigid wall. Data are obtained from a sequence of pictures made by a high speed camera. (Author/SLH)

  2. Cavity Ring down Spectroscopy Experiment for an Advanced Undergraduate Laboratory

    ERIC Educational Resources Information Center

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

    2007-01-01

    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…

  3. A Nonlinear, Multiinput, Multioutput Process Control Laboratory Experiment

    ERIC Educational Resources Information Center

    Young, Brent R.; van der Lee, James H.; Svrcek, William Y.

    2006-01-01

    Experience in using a user-friendly software, Mathcad, in the undergraduate chemical reaction engineering course is discussed. Example problems considered for illustration deal with simultaneous solution of linear algebraic equations (kinetic parameter estimation), nonlinear algebraic equations (equilibrium calculations for multiple reactions and…

  4. User Experience in Digital Games: Differences between Laboratory and Home

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  5. An Approach to Poiseuille's Law in an Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Sianoudis, I. A.; Drakaki, E.

    2008-01-01

    The continuous growth of computer and sensor technology allows many researchers to develop simple modifications and/or refinements to standard educational experiments, making them more attractive and comprehensible to students and thus increasing their educational impact. In the framework of this approach, the present study proposes an alternative…

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

    ERIC Educational Resources Information Center

    Foster, N.; And Others

    1985-01-01

    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)

  7. Millikan Oil-Drop Experiment in the Introductory Laboratory

    ERIC Educational Resources Information Center

    Heald, Mark A.

    1974-01-01

    Discusses a simplified Millikan oil-drop experiment which emphasizes the enplanation of basic concepts in mechanics and electrostatics, the use of home-made apparatus, the request for an individual's observation of his own drop, and the application of statistical analysis in data interpretation. (CC)

  8. Coulometric Analysis Experiment for the Undergraduate Chemistry Laboratory

    ERIC Educational Resources Information Center

    Dabke, Rajeev B.; Gebeyehu, Zewdu; Thor, Ryan

    2011-01-01

    An undergraduate experiment on coulometric analysis of four commercial household products is presented. A special type of coulometry cell made of polydimethylsiloxane (PDMS) polymer is utilized. The PDMS cell consists of multiple analyte compartments and an internal network of salt bridges. Experimental procedure for the analysis of the acid in a…

  9. Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System

    PubMed Central

    Blum, Jürgen; Beitz, Eike; Bukhari, Mohtashim; Gundlach, Bastian; Hagemann, Jan-Hendrik; Heißelmann, Daniel; Kothe, Stefan; Schräpler, Rainer; von Borstel, Ingo; Weidling, René

    2014-01-01

    For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust aggregates with sizes up to ~10 cm and porosities up to 70% can be collided. One of the drop towers is primarily used for very low impact speeds down to below 0.01 m/sec and makes use of a double release mechanism. Collisions are recorded in stereo-view by two high-speed cameras, which fall along the glass vacuum tube in the center-of-mass frame of the two dust aggregates. The other free-fall tower makes use of an electromagnetic accelerator that is capable of gently accelerating dust aggregates to up to 5 m/sec. In combination with the release of another dust aggregate to free fall, collision speeds up to ~10 m/sec can be achieved. Here, two fixed high-speed cameras record the collision events. In both drop towers, the dust aggregates are in free fall during the collision so that they are weightless and match the conditions in the early Solar System. PMID:24962693

  10. Laboratory drop towers for the experimental simulation of dust-aggregate collisions in the early solar system.

    PubMed

    Blum, Jürgen; Beitz, Eike; Bukhari, Mohtashim; Gundlach, Bastian; Hagemann, Jan-Hendrik; Heißelmann, Daniel; Kothe, Stefan; Schräpler, Rainer; von Borstel, Ingo; Weidling, René

    2014-06-05

    For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust aggregates with sizes up to ~10 cm and porosities up to 70% can be collided. One of the drop towers is primarily used for very low impact speeds down to below 0.01 m/sec and makes use of a double release mechanism. Collisions are recorded in stereo-view by two high-speed cameras, which fall along the glass vacuum tube in the center-of-mass frame of the two dust aggregates. The other free-fall tower makes use of an electromagnetic accelerator that is capable of gently accelerating dust aggregates to up to 5 m/sec. In combination with the release of another dust aggregate to free fall, collision speeds up to ~10 m/sec can be achieved. Here, two fixed high-speed cameras record the collision events. In both drop towers, the dust aggregates are in free fall during the collision so that they are weightless and match the conditions in the early Solar System.

  11. An investigation of the effects of the common cold on simulated driving performance and detection of collisions: a laboratory study

    PubMed Central

    Jamson, Samantha

    2012-01-01

    Objective The aim of the present research was to investigate whether individuals with a common cold showed impaired ability on a simulated driving task and the ability to detect potential collisions between moving objects. Design The study involved comparison of a healthy group with a group with colds. These scores were adjusted for individual differences by collecting further data when both groups were healthy and using these scores as covariates. On both occasions, volunteers rated their symptoms and carried out a simulated driving session. On the first occasion, volunteers also carried out a collision detection task. Setting University of Leeds Institute for Transport Studies. Sample Twenty-five students from the University of Leeds. Ten volunteers were healthy on both occasions and 15 had a cold on the first session and were healthy on the second. Main outcome measures In the collision detection task, the main outcomes were correct detections and response to a secondary identification task. In the simulated driving task, the outcomes were speed, lateral control, gap acceptance, overtaking behaviour, car following, vigilance and traffic light violations. Results Those with a cold detected fewer collisions and had a higher divided attention error than those who were healthy. Many basic driving skills were unimpaired by the illness. However, those with a cold were slower at responding to unexpected events and spent a greater percentage of time driving at a headway of <2 s. Conclusions The finding that having a common cold is associated with reduced ability to detect collisions and respond quickly to unexpected events is of practical importance. Further research is now required to examine the efficacy of information campaigns and countermeasures such as caffeine. PMID:22761287

  12. Real-time laboratory exercises to test contingency plans for classical swine fever: experiences from two national laboratories.

    PubMed

    Koenen, F; Uttenthal, A; Meindl-Böhmer, A

    2007-12-01

    In order to adequately and efficiently handle outbreaks of contagious diseases such as classical swine fever (CSF), foot and mouth disease or highly pathogenic avian influenza, competent authorities and the laboratories involved have to be well prepared and must be in possession of functioning contingency plans. These plans should ensure that in the event of an outbreak access to facilities, equipment, resources, trained personnel, and all other facilities needed for the rapid and efficient eradication of the outbreak is guaranteed, and that the procedures to follow are well rehearsed. It is essential that these plans are established during 'peace-time' and are reviewed regularly. This paper provides suggestions on how to perform laboratory exercises to test preparedness and describes the experiences of two national reference laboratories for CSF. The major lesson learnt was the importance of a well-documented laboratory contingency plan. The major pitfalls encountered were shortage of space, difficulties in guaranteeing biosecurity and sufficient supplies of sterile equipment and consumables. The need for a standardised laboratory information management system, that is used by all those involved in order to reduce the administrative load, is also discussed.

  13. The Heavy Photon Search experiment at Jefferson Laboratory

    NASA Astrophysics Data System (ADS)

    De Napoli, Marzio

    2015-06-01

    Many beyond Standard Model theories predict a new massive gauge boson, aka "dark" or "heavy photon", directly coupling to hidden sector particles with dark charge. The heavy photon is expected to mix with the Standard Model photon through kinetic mixing and therefore couple weakly to normal charge. The Heavy Photon Search (HPS) experiment will search for the heavy photon at the Thomas Jefferson National Accelerator Facility (JLab), in the mass range 20-1000 MeV/c2 and coupling to electric charge ɛ2 = α'/α in the range 10-5 to 10-10. HPS will look for the e+e- decay channel of heavy photons radiated by electron Bremsstrahlung, employing both invariant mass search and detached vertexing techniques. The experiment employs a compact forward spectrometer comprising silicon microstrip detectors for vertexing and tracking and an electromagnetic calorimeter for particle identification and triggering.

  14. Laser fusion experiments, facilities and diagnostics at Lawrence Livermore Laboratory

    SciTech Connect

    Ahlstrom, H.G.

    1980-02-01

    The progress of the LLL Laser Fusion Program to achieve high gain thermonuclear micro-explosions is discussed. Many experiments have been successfully performed and diagnosed using the large complex, 10-beam, 30 TW Shiva laser system. A 400 kJ design of the 20-beam Nova laser has been completed. The construction of the first phase of this facility has begun. New diagnostic instruments are described which provide one with new and improved resolution, information on laser absorption and scattering, thermal energy flow, suprathermal electrons and their effects, and final fuel conditions. Measurements were made on the absorption and Brillouin scattering for target irradiations at both 1.064 ..mu..m and 532 nm. These measurements confirm the expected increased absorption and reduced scattering at the shorter wavelength. Implosion experiments have been performed which have produced final fuel densities over the range of 10x to 100x liquid DT density.

  15. The Heavy Photon Search experiment at Jefferson Laboratory

    SciTech Connect

    De Napoli, Marzio

    2015-06-01

    Many beyond Standard Model theories predict a new massive gauge boson, a.k.a. 'dark' or 'heavy photon', directly coupling to hidden sector particles with dark charge. The heavy photon is expected to mix with the Standard Model photon through kinetic mixing and therefore couple weakly to normal charge. The Heavy Photon Search (HPS) experiment will search for the heavy photon at the Thomas Jefferson National Accelerator Facility (JLab), in the mass range 20-1000 MeV/c2 and coupling to electric charge ϵ2 = α'/α in the range 10-5 to 10-10. HPS will look for the e+e- decay channel of heavy photons radiated by electron Bremsstrahlung, employing both invariant mass search and detached vertexing techniques. The experiment employs a compact forward spectrometer comprising silicon microstrip detectors for vertexing and tracking and an electromagnetic calorimeter for particle identification and triggering.

  16. Experimenting with Impacts in a Conceptual Physics or Descriptive Astronomy Laboratory

    ERIC Educational Resources Information Center

    LoPresto, Michael C.

    2016-01-01

    What follows is a description of the procedure for and results of a simple experiment on the formation of impact craters designed for the laboratory portions of lower mathematical-level general education science courses such as conceptual physics or descriptive astronomy. The experiment provides necessary experience with data collection and…

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

    ERIC Educational Resources Information Center

    Vernengo, Jennifer; Purdy, Caitlin; Farrell, Stephanie

    2014-01-01

    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…

  18. Insights into oil cracking based on laboratory experiments

    USGS Publications Warehouse

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

    2003-01-01

    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.

  19. Laboratory and clinical experience with neodymium:YAG laser prostatectomy

    NASA Astrophysics Data System (ADS)

    Kabalin, John N.

    1996-05-01

    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.

  20. J/psi yield modification in 200 GeV per nucleon AU+AU collisions with the PHENIX experiment at RHIC

    NASA Astrophysics Data System (ADS)

    Klatsky, Jeffrey Curry

    It has been believed for over 30 years that matter will become a deconfined state of quarks and. gluons at sufficiently high energy densities. As the energy density increases, deconfinement occurs. due to Debye screening of the color charges, which disrupts the binding of mesons and baryons. The. expected deconfinement transition to quark-gluon plasma (QGP) has been observed using collisions. of heavy ions to create high energy densities,first at the Relativistic Heavy Ion Collider (RHIC). at Brookhaven National Laboratory, and more recently at the Large Hadron Collider (LHC) at. European Organization for Nuclear Research (CERN). The degree to which the binding of a hadron in the plasma is disrupted depends on its radius. Because deconfinement is caused by Debye screening, and the screening length is determined by. energy density, small tightly bound heavy quark mesons (referred to as quarkonia) may become. deconfined at a higher energy density than the light quark hadrons. Thus, measuring quarkonia. production may provide a way to determine the screening length in the QGP, and a program of. measurements of modification of charmonium and bottomonium states in heavy ion collisions has. been carried out at several accelerators over the last two decades. As part of this effort, measurements of J/psi production in Au+Au collisions have been made by the. PHENIX experiment at RHIC, the subject of this thesis. Specifically, J/psi --> e+e- data from. Sqrt(sNN) = 200 GeV Au+Au collisions were recorded in 2004, providing the first major quarkonia result from PHENIX. A higher statistics measurement was performed in 2007, but a non-functioning detector. subsystem in the PHENIX central arms rendered the data unusable. A still larger data set was. recorded 2010, this time with the previously non-functioning detector system working. It is these. 2010 data that are the focus of the present analysis. The 2010 dataset contains about 5 times as many measured J/psi as the 2004 dataset

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

    PubMed Central

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

    2014-01-01

    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

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

    PubMed

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

    2014-01-01

    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.

  3. Using Laboratory Experiments and Circuit Simulation IT Tools in an Undergraduate Course in Analog Electronics

    ERIC Educational Resources Information Center

    Baltzis, Konstantinos B.; Koukias, Konstantinos D.

    2009-01-01

    Laboratory-based courses play a significant role in engineering education. Given the role of electronics in engineering and technology, laboratory experiments and circuit simulation IT tools are used in their teaching in several academic institutions. This paper discusses the characteristics and benefits of both methods. The content and structure…

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

    ERIC Educational Resources Information Center

    Leung, Sam H.; Angel, Stephen A.

    2004-01-01

    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.

  5. An Analysis of High School Students' Perceptions and Academic Performance in Laboratory Experiences

    ERIC Educational Resources Information Center

    Mirchin, Robert Douglas

    2012-01-01

    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…

  6. Investigating Affective Experiences in the Undergraduate Chemistry Laboratory: Students' Perceptions of Control and Responsibility

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Malakpa, Zoebedeh; Bretz, Stacey Lowery

    2016-01-01

    Meaningful learning requires the integration of cognitive and affective learning with the psychomotor, i.e., hands-on learning. The undergraduate chemistry laboratory is an ideal place for meaningful learning to occur. However, accurately characterizing students' affective experiences in the chemistry laboratory can be a very difficult task. While…

  7. Seeking More Effective Outcomes from Science Laboratory Experiences (Grades 7-14): Six Companion Studies.

    ERIC Educational Resources Information Center

    Sutman, Frank X.; And Others

    The series of three sets of companion studies reported in this presentation addresses the need for seeking more effective outcomes from science laboratory experiences, which is indicated by conflicting outcomes of earlier reported research related to laboratory instruction at two different academic levels--grades 7-12 and beginning college. Four…

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

    ERIC Educational Resources Information Center

    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

    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…

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

    ERIC Educational Resources Information Center

    Feist, Patty L.

    2008-01-01

    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…

  10. Subpicosecond compression experiments at Los Alamos National Laboratory

    SciTech Connect

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

    1995-09-01

    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.

  11. An HP 85 Microcomputer for Experiment Control in the Physics Laboratory.

    ERIC Educational Resources Information Center

    Walrand, Jacques; And Others

    1983-01-01

    Describes a simple and inexpensive interface to be used for data acquisition and control of some experiments in an undergraduate physics laboratory. Two specific applications are presented. Seven references are listed. (Author/MBR)

  12. Determination of Rate Constants for Ouabain Inhibition of Adenosine Triphosphatase: An Undergraduate Biological Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Sall, Eri; And Others

    1978-01-01

    Describes an undergraduate biological chemistry laboratory experiment which provides students with an example of pseudo-first-order kinetics with the cardiac glycoside inhibition of mammalism sodium and potassium transport. (SL)

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

    ERIC Educational Resources Information Center

    Tsionsky, Vladimir

    2007-01-01

    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.

  14. An Experiment Using Sucrose Density Gradients in the Undergraduate Biochemistry Laboratory.

    ERIC Educational Resources Information Center

    Turchi, Sandra L.; Weiss, Monica

    1988-01-01

    Describes an experiment to be performed in an undergraduate biochemistry laboratory that is based on a gradient centrifugation system employing a simple bench top centrifuge, a freezer, and frozen surcose gradient solution to separate macromolecules and subcellular components. (CW)

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

    ERIC Educational Resources Information Center

    Sotheeswaran, Subramaniam

    1988-01-01

    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)

  16. Imidazole as a pH Probe: An NMR Experiment for the General Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hagan, William J., Jr.; Edie, Dennis L.; Cooley, Linda B.

    2007-01-01

    The analysis describes an NMR experiment for the general chemistry laboratory, which employs an unknown imidazole solution to measure the pH values. The described mechanism can also be used for measuring the acidity within the isolated cells.

  17. EM techniques for archaeological laboratory experiments: preliminary results

    NASA Astrophysics Data System (ADS)

    Capozzoli, Luigi; De Martino, Gregory; Giampaolo, Valeria; Raffaele, Luongo; Perciante, Felice; Rizzo, Enzo

    2015-04-01

    The electromagnetic techniques (EM) are based on the investigation of subsoil geophysical parameters and in the archaeological framework they involve in studying contrasts between the buried cultural structures and the surrounding materials. Unfortunately, the geophysical contrast between archaeological features and surrounding soils sometimes are difficult to define due to problems of sensitivity and resolution both related on the characteristic of the subsoil and the geophysical methods. For this reason an experimental activity has been performed in the Hydrogeosite laboratory addressed on the assessment of the capability of geophysical techniques to detect archeological remains placed in the humid/saturated subsoil. At Hydrogeosite Laboratory of CNR-IMAA, a large scale sand-box is located, consisting on a pool shape structures of 230m3 where archaeological remains have been installed . The remains are relative to a living environment and burial of Roman times (walls, tombs, roads, harbour, etc.) covered by sediments. In order to simulate lacustrine and wetland condition and to simulate extreme events (for example underwater landslide, fast natural erosion coast, etc.) the phreatic level was varied and various acquisitions for the different scenarios were performed. In order to analyze the EM behavior of the buried small archaeological framework, ground penetrating radar (GPR) and electrical resistivity tomographies were performed. With GPR, analysis in time domain and frequency domain were performed and coupled to information obtained through resistivity analysis with the support of numerical simulations used to compare the real data with those modeled. A dense grid was adopted for 400 and 900 MHz e-m acquisitions in both the directions, the maximum depth of investigation was limited and less than 3 meters. The same approach was used for ERT acquisition where different array are employed, in particular 3D configuration was used to carry out a 3D resistivity

  18. Evaporation of J13 water: laboratory experiments and geochemical modeling

    SciTech Connect

    Dibley, M.J.; Knauss, K.G.; Rosenberg, N.D.

    1999-08-11

    We report results from experiments on the evaporative chemical evolution of synthetic J13 water, representative of water from well J13, a common reference water in the Yucca Mountain Project. Data include anion and cation analysis and qualitative mineral identification for a series of open system experiments, with and without crushed tuff present, conducted at sub-boiling temperatures. Ca and Mg precipitated readily as carbonates and anions Cl, F, NO{sub 3} and SO{sub 4} remained in solution in nearly identical ratios. The pH stabilized at about 10. After {approx} 1000x concentration, the minerals formed were amorphous silica, aragonite and calcite. The presence of tuff appears to have very little effect on the relative distribution of the anions in solution, except for possibly F, which had a relatively lower concentration ratio. The Si was lower in the solutions with tuff present suggesting that the tuff enhances SiO{sub 2} precipitation. Even though the tools to model highly-concentrated salt solutions are limited, we compare our experimental results with the results of geochemical models, with (perhaps) surprising good results. In response to different assumed CO{sub 2} levels, pH varied, but anion concentrations were not greatly affected.

  19. Geochemistry of shale groundwaters: Results of preliminary laboratory leaching experiments

    SciTech Connect

    Von Damm, K.L.; Johnson, K.O.

    1987-09-01

    Twelve shales were reacted with distilled water at 20/sup 0/C and 100/sup 0/C; the composition of the waters and the mineralogy were determined before and after reaction. The experiments were conducted in a batch mode over a period of approximately 40 days. Major changes occurred in the solution chemistry; in most cases sulfate became the dominant anion while either sodium or calcium was the major cation. The high sulfate is most likely a result of the oxidation of pyrite in the samples. In the 100/sup 0/C experiments some of the solutions became quite acidic. Examination of the observed mineralogy and comparison to the mineral assemblage calculated to be in equilibrium with the experimentally determined waters, suggests that the acidic waters are generated when no carbonate minerals remain to buffer the groundwaters to a more neutral pH. The pH of shale waters will be determined by the balance between the oxidation of pyrite and organic matter and the dissolution of carbonate minerals. The experimental data are helping to elucidate the chemical reactions that control the pH of shale groundwaters, a critical parameter in determining other water-rock and waste-water-rock interactions and ultimate solute mobility. An experimental approach also provides a means of obtaining data for shales for which no groundwater data are available as well as data on chemical species which are not usually determined or reported.

  20. Researches on interactions of satellite-speed helium atoms with aluminum and quartz surfaces. [atomic collisions with aluminum skin (structural member) of satellites (laboratory study)

    NASA Technical Reports Server (NTRS)

    Liu, S. M.; Knuth, E. L.

    1976-01-01

    Three major areas were experimentally studied: (1) energy transfer in collisions of satellite-speed (700 m/sec) helium atoms with a cleaned satellite-type aluminum surface was investigated using the molecular-beam technique. Spatial and energy distributions of reflected helium atoms were measured and analyzed, (2) The gross accommodation coefficient for a satellite-speed (7000 m/sec) helium beam entering a 2-inch-diameter aluminum spherical cavity was determined by measuring the exit velocity distribution of the leaving helium atoms using a metastable time-of-flight method. Results indicate that the 7000-m/sec satellite-speed helium atoms entering the cavity gain full accommodation with the room-temperature inner surface of the sphere through a large number of collisions before leaving the spherical cavity; and (3) the feasibility of producing a satellite-speed atomic hydrogen beam by arc-heating, for use in studies of interactions of satellite-surfaces with hydrogen atoms under laboratory conditions, was investigated. It was found that a stable arc-heated molecular hydrogen beam can be obtained using the arc-heater, and that a partially dissociated hydrogen beam can be produced. Photographs of laboratory equipment are shown.

  1. Artist rendition of the planned Space Experiment Research and Processing Laboratory

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The preliminary design for the Space Experiment Research and Processing Laboratory (SERPL) at Kennedy Space Center is shown in this artist's rendition. The SERPL is a planned 100,000-square- foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

  2. Compressed natural gas and liquefied petroleum gas conversions: The National Renewable Energy Laboratory`s experience

    SciTech Connect

    Motta, R.C.; Kelly, K.J.; Warnock, W.W.

    1996-04-01

    The National Renewable Energy Laboratory (NREL) contracted with conversion companies in six states to convert approximately 900 light-duty Federal fleet vehicles to operate on compressed natural gas (CNG) or liquefied petroleum gas (LPG). The contracts were initiated in order to help the Federal government meet the vehicle acquisition requirements of the Energy Policy Act of 1992 (EPACT) during a period of limited original equipment manufacturer (OEM) model availability. Approximately 90% of all conversions were performed on compact of full-size vans and pickups, and 90% of the conversions were to bi-fuel operation. With a positive response from the fleet managers, this program helped the Federal government meet the vehicle acquisition requirements of EPACT for fiscal years 1993 and 1994, despite limited OEM model availability. The conversions also helped to establish the infrastructure needed to support further growth in the use of alternative fuel vehicles. In conclusion, the program has been successful in helping the Federal government meet the vehicle acquisition requirements of EPACT, establishing infrastructure, increasing the displacement of imported oil, and evaluating the emissions performance of converted vehicles. With the relatively widespread availability of OEM vehicles in the 1996 model year, the program is now being phased out.

  3. Search for relativistic electrons in laboratory discharge experiments

    NASA Astrophysics Data System (ADS)

    Ostgaard, Nikolai; Carlson, Brant E.; Grøndahl, Øystein; Kochkin, Pavlo; Nisi, Ragnhild S.; Gjesteland, Thomas

    2015-04-01

    Discharge experiments were carried out at the Technical University of Eindhoven in 2013. The experimental set-up was designed to search for electrons produced in meter-scale sparks using a 1 MV Marx generator. Negative voltage was applied to the HV electrode. Five thin (1 mm) plastic detectors (5 cm2 each) were distributed in various configurations close to the spark gap. Earlier studies have shown (for HV negative) that X-rays are produced when a cloud of streamers has developed 30-60 cm from the negative electrode. This indicates that the electrons producing the X-rays are also accelerated in this location, probably in the strong electric field from countestreaming streamers of opposite polarity. Comparing our measurements with modeling results we find that 200-400 keV electrons produced about 30-60 cm from the negative electrode is the most likely source of our measurements.

  4. From laboratory experiments to LISA Pathfinder: achieving LISA geodesic motion

    NASA Astrophysics Data System (ADS)

    Antonucci, F.; Armano, M.; Audley, H.; Auger, G.; Benedetti, M.; Binetruy, P.; Boatella, C.; Bogenstahl, J.; Bortoluzzi, D.; Bosetti, P.; Brandt, N.; Caleno, M.; Cavalleri, A.; Cesa, M.; Chmeissani, M.; Ciani, G.; Conchillo, A.; Congedo, G.; Cristofolini, I.; Cruise, M.; Danzmann, K.; De Marchi, F.; Diaz-Aguilo, M.; Diepholz, I.; Dixon, G.; Dolesi, R.; Dunbar, N.; Fauste, J.; Ferraioli, L.; Fertin, D.; Fichter, W.; Fitzsimons, E.; Freschi, M.; García Marin, A.; García Marirrodriga, C.; Gerndt, R.; Gesa, L.; Giardini, D.; Gibert, F.; Grimani, C.; Grynagier, A.; Guillaume, B.; Guzmán, F.; Harrison, I.; Heinzel, G.; Hewitson, M.; Hollington, D.; Hough, J.; Hoyland, D.; Hueller, M.; Huesler, J.; Jeannin, O.; Jennrich, O.; Jetzer, P.; Johlander, B.; Killow, C.; Llamas, X.; Lloro, I.; Lobo, A.; Maarschalkerweerd, R.; Madden, S.; Mance, D.; Mateos, I.; McNamara, P. W.; Mendes, J.; Mitchell, E.; Monsky, A.; Nicolini, D.; Nicolodi, D.; Nofrarias, M.; Pedersen, F.; Perreur-Lloyd, M.; Perreca, A.; Plagnol, E.; Prat, P.; Racca, G. D.; Rais, B.; Ramos-Castro, J.; Reiche, J.; Romera Perez, J. A.; Robertson, D.; Rozemeijer, H.; Sanjuan, J.; Schleicher, A.; Schulte, M.; Shaul, D.; Stagnaro, L.; Strandmoe, S.; Steier, F.; Sumner, T. J.; Taylor, A.; Texier, D.; Trenkel, C.; Tombolato, D.; Vitale, S.; Wanner, G.; Ward, H.; Waschke, S.; Wass, P.; Weber, W. J.; Zweifel, P.

    2011-05-01

    This paper presents a quantitative assessment of the performance of the upcoming LISA Pathfinder geodesic explorer mission. The findings are based on the results of extensive ground testing and simulation campaigns using flight hardware, flight control and operations algorithms. The results show that, for the central experiment of measuring the stray differential acceleration between the LISA test masses, LISA Pathfinder will be able to verify the overall acceleration noise to within a factor 2 of the LISA requirement at 1 mHz and within a factor 6 at 0.1 mHz. We also discuss the key elements of the physical model of disturbances, coming from LISA Pathfinder and ground measurement that will guarantee the LISA performance.

  5. MULTIFRACTAL AND MONOFRACTAL SCALING IN A LABORATORY MAGNETOHYDRODYNAMIC TURBULENCE EXPERIMENT

    SciTech Connect

    Schaffner, D. A.; Brown, M. R.

    2015-09-20

    Both multifractal and monofractal scaling of structure function exponents are observed in the turbulent magnetic fluctuations of the Swarthmore Spheromak Experiment plasma. Structure function and probability distribution function (PDF) analysis exhibits multifractal scaling exponents in low frequency, inertial range fluctuations of the turbulence but monofractal scaling in higher frequency, dissipation range fluctuations. The transition from multifractal to monofractal scaling occurs rapidly suggesting a dissipation mechanism that is insensitive to turbulent structure scale size. Structure functions and PDFs are presented for both temporal and spatial measurements. Variations in the magnetic helicity in the plasma are also shown to modify multifractal scaling characteristics of the inertial range, but do not affect the monofractal scaling of the dissipation range.

  6. Subpicosecond Compression Experiments at Los Alamos National Laboratory

    SciTech Connect

    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.

    1996-04-01

    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.}

  7. Relationship between magnetic susceptibility and strain in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham; Alford, Craig

    1987-02-01

    Under experimental conditions of 1.5 kbar confining pressure and at a strain-rate of 5 × 10 -6 sec -1 at room temperature the principal directions of magnetic susceptibility of a dry, synthetic, magnetite-bearing sandstone rotate toward principal strain directions. The rotation is faster than that expected from rotation of a line in homogeneous strain. Fluid pressures of 200 or 700 bars do not appear to affect the development of anisotropy of susceptibility. The change in bulk anisotropy shows a power law correlation with strain ratio where the initial susceptibility ellipsoid was nearly coaxial with the bulk strain axes during the experiment. More generally, in those situations, as well as ones in which the initial susceptibility ellipsoid was strongly inclined to the bulk strain axes there exists a common matrix M which relates the initial susceptibility tensor kij, the final susceptibility tensor k' ij and the strain tensor eij: eijk' ij = Mk' ij

  8. Laboratory Experiments on Core Merging and Stratification After Giant Impacts

    NASA Astrophysics Data System (ADS)

    Landeau, M.; Olson, P.; Deguen, R.; Hirsh, B.

    2015-12-01

    The fluid dynamics of core merging after giant impacts in the late stages of accretion provides constraints on metal-silicate equilibration, core stratification, and early magnetic field generation. The energy released during giant impacts, such as those thought to have formed Earth's Moon and the crustal dichotomy on Mars, likely resulted in melting of the impactor and much or all of the protoplanet's mantle. Under these conditions, the liquid core of the impactor migrates through a fully-liquid magma ocean, and merges with the protoplanet's core. Unlike the laminar flow in numerical simulations, liquid impact experiments can produce turbulence, as expected during core formation. We present experiments on liquid blobs of variable density released into another liquid consisting of two immiscible layers, representing the magma ocean and protocore, respectively. The released liquid is denser than the upper layer, immiscible in the upper layer, and miscible in the lower layer. With a shallow upper layer, the relevant regime for giant impacts, a turbulent cloud of released and upper liquids penetrates into the lower layer, collapses and spreads along the interface between the upper and lower layers. This behavior contrasts with the laminar core merging observed in impact simulations or the classical iron rain scenario, and suggests that metal-silicate chemical equilibration extends inside the protocore. Experimental scalings for low-density releases predict that compositional stratification of the core is likely in the aftermath of planet formation, and the stratified layer detected by seismology at the top of Earth's core is compatible with a moon-forming impact. By implication, the early core dynamo had to overcome compositional stratification to initiate.

  9. The First Transverse Single Spin Measurement in High Energy Polarized Proton-Nucleus Collision at the PHENIX experiment at RHIC

    NASA Astrophysics Data System (ADS)

    Nakagawa, I.

    2016-08-01

    Large single spin asymmetries in very forward neutron production seen using the PHENIX zero-degree calorimeters are a long established feature of transversely polarized proton-proton collisions at RHIC. Neutron production near zero degrees is well described by the one-pion exchange framework. The absorptive correction to the OPE generates the asymmetry as a consequence of a phase shift between the spin flip and non-spin flip amplitudes. However, the amplitude predicted by the OPE is too small to explain the large observed asymmetries. A model introducing interference of pion and a 1-Reggeon exchanges has been successful in reproducing the experimental data. During the RHIC experiment in year 2015, RHIC delivered polarized proton collisions with Au and Al nuclei for the first time, enabling the exploration of the mechanism of transverse single-spin asymmetries with nuclear collisions. The observed asymmetries showed surprisingly strong A-dependence in the inclusive forward neutron production, while the existing framework which was successfull in p+p only predicts moderate A- dependence. Thus the observed data are absolutely unexpected and unpredicted. In this report, experimental and theoretical efforts are discussed to disentangle the observed A-dependence using somewhat semi-inclusive type measurements and Monte-Carlo study, respectively.

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

    PubMed

    Kopaladze, R A

    2004-01-01

    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.

  11. Laboratory experiments with heterogeneous reactions in mixed porous media

    SciTech Connect

    Burris, D.R.; Hatfield, K.; Wolfe, N.L.

    1996-08-01

    The limited success and high cost of traditional active ground-water-contaminant plume management efforts (i.e., pump-and-treat systems) has stimulated a search for less expensive passive plume interception and in-situ treatment technologies. The funnel/gate system, which uses heterogeneous (surface-mediated) reactions on porous media to degrade dissolved contaminants, is one passive technology under consideration. Research on a heterogeneous reaction is presented in this paper, which can be extended to facilitate the design of engineered porous media systems (i.e., funnel/gates). Results are examined from batch and flow-through column experiments involving nitrobenzene degradation in a surface-mediated reaction with granular metallic iron. A nonequilibrium transport model that incorporates solute mass-transfer resistance near reactive iron surfaces is shown to simulate breakthrough curves (BTCs) from column systems, using model parameters estimated from batch systems. The investigation shows pseudo first-order degradation-rate coefficients increasing with higher solid:liquid ratios and with greater iron concentrations. In addition, nitrobenzene degradation is found to be faster in batch systems than in comparable column systems, indicating the presence of mass-transfer limitations in the flow-through systems. Finally, the present study provides insights on conditions pertinent to the design of engineered in-situ treatment zones, such as how mass-transfer, hydraulic, and reaction kinetic conditions affect ground-water-contaminant fate and transport through reactive porous media.

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

    NASA Astrophysics Data System (ADS)

    Hodges, Linda C.

    1995-12-01

    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.

  13. The LBL (Lawrence Berkeley Laboratory) multiple beam experiments

    SciTech Connect

    Fessenden, T.J.; Keefe, D.; Kim, C.; Meuth, H.; Warwick, A.

    1987-03-01

    The multiple-beam induction linac approach to a heavy ion driver for inertial confinement, fusion features continuous current amplification along the accelerator and a minimum of beam manipulations from source to pellet. Current amplification and bunch length control require careful shaping of the accelerating voltages. MBE-4 is designed as a four-beam induction linac that models much of the accelerator physics of the electrostatically focused section of a significantly longer induction accelerator. Four space-charge-dominated Cs/sup +/ beams, initially about one meter in length at a current of 13 mA, are focused by electrostatic quadrupoles and accelerated in parallel from 200 to nearly 600 keV. The energy will reach approximately one MeV when the accelerator is complete. Experiments have proceeded in parallel with the construction of the apparatus which began in FY 85 and is now more than half complete. The results show a current amplification, so far, by a factor of 2.8 in good agreement with the longitudinal acceleration calculations.

  14. Closing the loop on improvement: Packaging experience in the Software Engineering Laboratory

    NASA Technical Reports Server (NTRS)

    Waligora, Sharon R.; Landis, Linda C.; Doland, Jerry T.

    1994-01-01

    As part of its award-winning software process improvement program, the Software Engineering Laboratory (SEL) has developed an effective method for packaging organizational best practices based on real project experience into useful handbooks and training courses. This paper shares the SEL's experience over the past 12 years creating and updating software process handbooks and training courses. It provides cost models and guidelines for successful experience packaging derived from SEL experience.

  15. The development of the AFIT Communications Laboratory and experiments for communications students

    NASA Astrophysics Data System (ADS)

    Thompson, J. B.

    1985-12-01

    This thesis was a development of a series of experiments for an electronics communications laboratory. These experiments were designed to reinforce theoretical courses offered in the Air Force Institute of Technology Electrical Engineering Core Communications Sequence in the form of demonstrations or laboratory exercises. The experiments were developed under the criteria of investigating a significant number of analog and digital communication system concepts with a minimum amount of experimentation time. Extensive use of a spectrum analyzer was included in many of the experiments. The topics covered in the experiments include: amplitude modulation; frequency modulation; balanced modulator; single sideband modulation; phase-lock loop and frequency synthesizer; pulse amplitude modulation; pulse code modulation; delta modulation; amplitude shift keying; phase shift keying; and frequency shift keying. The results of this study indicated that many more system concepts could be included in laboratory exercises, such as spread spectrum communications time and frequency division multiplexing, and computer oriented testing and analysis.

  16. Oscillating load-induced acoustic emission in laboratory experiment

    USGS Publications Warehouse

    Ponomarev, Alexander; Lockner, David A.; Stroganova, S.; Stanchits, S.; Smirnov, V.

    2010-01-01

    Spatial and temporal patterns of acoustic emission (AE) were studied. A pre-fractured cylinder of granite was loaded in a triaxial machine at 160 MPa confining pressure until stick-slip events occurred. The experiments were conducted at a constant strain rate of 10−7 s−1 that was modulated by small-amplitude sinusoidal oscillations with periods of 175 and 570 seconds. Amplitude of the oscillations was a few percent of the total load and was intended to simulate periodic loading observed in nature (e.g., earth tides or other sources). An ultrasonic acquisition system with 13 piezosensors recorded acoustic emissions that were generated during deformation of the sample. We observed a correlation between AE response and sinusoidal loading. The effect was more pronounced for higher frequency of the modulating force. A time-space spectral analysis for a “point” process was used to investigate details of the periodic AE components. The main result of the study was the correlation of oscillations of acoustic activity synchronized with the applied oscillating load. The intensity of the correlated AE activity was most pronounced in the “aftershock” sequences that followed large-amplitude AE events. We suggest that this is due to the higher strain-sensitivity of the failure area when the sample is in a transient, unstable mode. We also found that the synchronization of AE activity with the oscillating external load nearly disappeared in the period immediately after the stick-slip events and gradually recovered with further loading.

  17. Laboratory experiments on Radiative Shocks relevant to Stellar Accretion

    NASA Astrophysics Data System (ADS)

    Chaulagain, Uddhab

    2015-08-01

    Radiative shocks are strong shocks which are characterized by a plasma at high temperatures emitting an important fraction of its energy as radiation. Radiative shocks are found in many astrophysical systems, including stellar accretion shocks, supernovae remnants, jet driven shocks, etc. In the case of stellar accretion, matter is funneled into accretion columns by the stellar magnetic field, and falls at several hundreds km/s from the circumstellar envelope onto the stellar photosphere. This generates a strong radiative shock with x-ray spectral signatures that are a key ingredient to quantify the mass accretion rate. The physical structure and dynamics of such plasmas is complex, and experimental benchmarks are needed to provide a deeper understanding of the physics at play.Recently, radiative shocks have also been produced experimentally using high energy lasers. We discuss the results of an experiment performed on the Prague Asterix Laser System (PALS) facility. Shocks are generated by focusing the PALS Infrared laser beam on millimetre-scale targets filled with xenon gas at low pressure. The shock that is generated then propagates in the gas with a sufficiently high velocity such that the shock is in a radiative flux dominated regime. We will present the first instantaneous imaging of a radiative shock at 21.2 nm which is characterized by the presence of both the radiative precursor and the post shock structure. These results are complemented with time-and-space resolved XUV plasma self-emission measurements using fast diodes. Interpretation of the data, supported by numerical simulations using the 2-D radiative-hydrodynamics code ARWEN, will be presented showing the importance of radiative processes from atomic to larger scales.

  18. In-house experiments in large space structures at the Air Force Wright Aeronautical Laboratories Flight Dynamics Laboratory

    NASA Technical Reports Server (NTRS)

    Gordon, Robert W.; Ozguner, Umit; Yurkovich, Steven

    1989-01-01

    The Flight Dynamics Laboratory is committed to an in-house, experimental investigation of several technical areas critical to the dynamic performance of future Air Force large space structures. The advanced beam experiment was successfully completed and provided much experience in the implementation of active control approaches on real hardware. A series of experiments is under way in evaluating ground test methods on the 12 meter trusses with significant passive damping. Ground simulated zero-g response data from the undamped truss will be compared directly with true zero-g flight test data. The performance of several leading active control approaches will be measured and compared on one of the trusses in the presence of significant passive damping. In the future, the PACOSS dynamic test article will be set up as a test bed for the evaluation of system identification and control techniques on a complex, representative structure with high modal density and significant passive damping.

  19. A novel approach to collision-induced dissociation (CID) for ion mobility-mass spectrometry experiments.

    PubMed

    Becker, Christopher; Fernandez-Lima, Francisco A; Gillig, Kent J; Russell, William K; Cologna, Stephanie M; Russell, David H

    2009-06-01

    Collision induced dissociation (CID) combined with matrix assisted laser desorption ionization-ion mobility-mass spectrometry (MALDI-IM-MS) is described. In this approach, peptide ions are separated on the basis of mobility in a 15 cm drift cell. Following mobility separation, the ions exit the drift cell and enter a 5 cm vacuum interface with a high field region (up to 1000 V/cm) to undergo collisional activation. Ion transmission and ion kinetic energies in the interface are theoretically evaluated accounting for the pressure gradient, interface dimensions, and electric fields. Using this CID technique, we have successfully fragmented and sequenced a number of model peptide ions as well as peptide ions obtained by a tryptic digest. This instrument configuration allows for the simultaneous determination of peptide mass, peptide-ion sequence, and collision-cross section of MALDI-generated ions, providing information critical to the identification of unknown components in complex proteomic samples.

  20. D0 Meson Production in Heavy Ion Collisions in CMS experiment

    NASA Astrophysics Data System (ADS)

    Wang, Jing; CMS Collaboration

    2017-01-01

    The measurement of heavy flavour production is a powerful tool to study the properties of the high-density QCD medium created in heavy-ion collisions as heavy quarks are sensitive to the transport properties of the medium and may interact with the QCD matter differently from light quarks. In particular, the comparison between the nuclear modification factors of light and heavy flavoured particles provides insights into the expected flavour dependence of in-medium parton energy loss. With the CMS detector, the D0 meson production is studied in pp and PbPb collisions at 2.76 and 5.02 TeV. In this talk, the nuclear modification factor of D0 meson are presented and compared to the charged hadron nuclear modification factor and theoretical calculations.

  1. Space Weathering Effects on Sulfates and Carbonates: Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Dukes, Catherine; Bu, Caixia; Rodriguez lopez, Gerard; McFadden, Lucy Ann; Li, Jian-Yang; Ruesch, Ottaviano

    2016-10-01

    Introduction: The solar wind plasma continuously streams from the Sun, interacting with the surfaces of airless bodies throughout the solar system. Sulfates and carbonates, identified by the UV-Vis spectral slope [1] and 3.4 / 4.0 μm absorption features [2] on the surface of Ceres, will be exposed to solar H, He at ~1keV/amu. We investigate the stability of anhydrous salts under 4 keV He+ irradiation as proxy for the solar wind.Experiment: Anhydrous MgSO4, Na2SO4, and Na2CO3 powders are pressed into pellets, with compositions confirmed by XRD. Pellet samples are placed in ultra-high vacuum (10-9 Torr) and the effects of 4keV He+ irradiation on surface composition and chemistry are monitored by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy, as a function of ion fluence. We measure ex situ diffuse optical reflectance prior and subsequent to irradiation through ranges 0.2-2.5µm (Lambda 1050) and 0.6-10µm (Thermo Nicolet 670).Results: Ion irradiation of MgSO4 damages the crystal structure, preferentially removing oxygen along with sulfur. XPS measurements imply the formation of MgO after 5x1017 He+cm-2 (~15,000 years at 2.7AU). During irradiation, we observe secondary ion ejection (Mg, MgO, O, OH, H, S, and SO) and neutral SO2. In addition, XPS sulfur spectra suggest the presence of a small amount of trapped SO2, confirming this decomposition product observed in the optical UV spectra at ~240 and 280nm [3,4] with dehydration, as well as in the IR at ~7.8μm [5] with irradiation. Our observations are consistent with the potential decomposition pathway for MgSO4 to SO2 provided by McCord et al. (2001) [6]. Spectral darkening and reddening in the UV-Vis region after irradiation are observed by ex situ optical spectroscopy. We suggest that space weathering by solar ions limits the stability of salts on Ceres and other airless bodies, which influences the optical reflectance.Acknowledgements: We thank the NASA SSW program for support

  2. Laboratory experiments on turbulent mixing across sheared density interfaces

    NASA Astrophysics Data System (ADS)

    Stephenson, Philip; Fernando, Harindra J. S.

    1991-05-01

    An experimental study was carried out to investigate turbulent mixing and entrainment across a density interface subjected to velocity shear. The flow configuration consisted of a salinity (stably) stratified two-fluid system with a driven upper turbulent layer and a quiescent lower layer. The experiments were performed in an Odell-Kovasznay tank and the mean flow in the upper layer was generated by using a conventional disk pump. The velocity and salinity measurements were made using a laser-Doppler anemometer and conductivity probes, respectively, and (quantitative) flow visualization was performed using the laser-induced fluorescence LIF technique. The refractive indices of upper and lower layers were matched, using salt and alcohol, to facilitate the use of laser-based flow diagnostic techniques. The measurements show that the rms velocity fluctuation u in bulk of the mixed layer scales well with the mean velocity jump Δu across the interface. The Thorpe, buoyancy, overturning, and integral length scales, as well as the maximum Thorpe displacement in the mixed layer, were also found to be proportional to the depth h of the upper mixed layer. The structure of the entrainment interface was found to depend strongly on the bulk Richardson number Ri (=Δb h/u2), where Δb is the buoyancy jump across the interfacial layer. At lower Ri, the entrainment occurred rapidly, as in a nonstratified fluid, but as Ri increases, the entrainment rate becomes a strong function of Ri: under the latter conditions, the interfacial wave breaking and Kelvin-Helmholtz instabilities were common features. At still higher Ri, the entrainment rate becomes vanishingly small and the interfacial mixing events were found to be controlled by the molecular diffusive effects. The measurement of the interfacial-layer thickness using LIF shows that it is much thinner than that measured using less-accurate techniques such as traversing probes. The nondimensional rms amplitude of the interfacial

  3. Annotated List of Laboratory Experiments in Chemistry from the Journal of Chemical Education. Second Edition, 1957-1984.

    ERIC Educational Resources Information Center

    Allen, C. B.; And Others

    This document is the second edition of the Annotated List of Laboratory Experiments in Chemistry first published in 1980. All entries in the Journal of Chemical Education describing laboratory experiments in chemistry or laboratory descriptions suitable for student experiments or projects, for the years 1957-1984 inclusive, have been listed and…

  4. Inclusive photon production at forward rapidities in pp collisions at LHC energies with the ALICE experiment

    NASA Astrophysics Data System (ADS)

    Sudipan Dethe ALICE Collaboration

    2016-04-01

    Measurements of multiplicity and pseudorapidity distributions of particles produced in pp collisions are important for the study of particle production mechanisms and to obtain baseline distributions to be compared with those from heavy-ion collisions. The inclusive photon measurements (dominated by π0 decays) are complementary to the charged particle measurements. The present work focuses on the forward rapidity region with comparisons to different models such as PYTHIA and PHOJET. We report the measurements of multiplicity and pseudorapidity distributions of inclusive photons using the ALICE Photon Multiplicity Detector (PMD) at forward rapidities (2.3 < η < 3.9) in pp collisions at = 0.9, 2.76 and 7 TeV. It is observed that the photon multiplicity distributions are well described by negative binomial distributions (NBD). Multiplicity distributions are studied in terms of KNO variables for each energy. It is shown that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and power law dependence. The results are compared to different model predictions. These models reproduce experimental results at lower energy while they are not accurate at higher energies.

  5. Toward a deeper understanding of how experiments constrain the underlying physics of heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Sangaline, Evan; Pratt, Scott

    2016-02-01

    Recent work has provided the means to rigorously determine properties of superhadronic matter from experimental data through the application of broad scale modeling of high-energy nuclear collisions within a Bayesian framework. These studies have provided unprecedented statistical inferences about the physics underlying nuclear collisions by virtue of simultaneously considering a wide range of model parameters and experimental observables. Notably, this approach has been used to constrain both the QCD equation of state and the shear viscosity above the quark-hadron transition. Although the inferences themselves have a clear meaning, the complex nature of the relationships between model parameters and observables has remained relatively obscure. We present here a novel extension of the standard Bayesian Markov-chain Monte Carlo approach that allows for the quantitative determination of how inferences of model parameters are driven by experimental measurements and their uncertainties. This technique is then applied in the context of heavy-ion collisions in order to explore previous results in greater depth. The resulting relationships are useful for identifying model weaknesses, prioritizing future experimental measurements, and, most importantly, developing an intuition for the roles that different observables play in constraining our understanding of the underlying physics.

  6. New level-resolved collision data for neutral argon, benchmarked against the ALEXIS plasma experiment

    NASA Astrophysics Data System (ADS)

    Arnold, Nicholas; Loch, Stuart; Ballance, Connor; Thomas, Ed

    2016-10-01

    Performing spectroscopic measurements of emission lines in low temperature laboratory plasmas is challenging because the plasma is often neutral-dominated and not in thermal equilibrium. The densities and temperatures are such that coronal models do not apply; meaning that generalized collisional-radiative (GCR) methods must be employed to theoretically analyze atomic processes. However, for most noble gases, detailed, level-resolved atomic data for neutral and low-charge states does not exist in the literature. We report on a new project, where we use existing atomic physics codes to calculate level-resolved atomic data for neutral and low charge states of argon and compare with previously published, term-resolved theoretical results. In addition, we use the Atomic Structure and Data Analysis (ADAS) suite of codes to calculate a GCR model for low temperature neutral argon, which we compare to published measurements of argon optical emission cross sections. Finally, we compare synthetic spectra generated from our data with observations taken from the Auburn Linear Experiment for Instability Studies (ALEXIS) in an attempt to develop new optical plasma diagnostics for electron temperature and plasma density measurements. This project is supported by the U.S. Department of Energy. Grant Number: DE-FG02-00ER54476.

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

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  8. Thermodynamic Exploration of Eosin-Lysozyme Binding: A Physical Chemistry and Biochemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Huisman, Andrew J.; Hartsell, Lydia R.; Krueger, Brent P.; Pikaart, Michael J.

    2010-01-01

    We developed a modular pair of experiments for use in the undergraduate physical chemistry and biochemistry laboratories. Both experiments examine the thermodynamics of the binding of a small molecule, eosin Y, to the protein lysozyme. The assay for binding is the quenching of lysozyme fluorescence by eosin through resonant energy transfer. In…

  9. Designing an Acoustic Suspension Speaker System in the General Physics Laboratory: A Divergent experiment

    ERIC Educational Resources Information Center

    Horton, Philip B.

    1969-01-01

    Describes a student laboratory project involving the design of an "acoustic suspension speaker system. The characteristics of the loudspeaker used are measured as an extension of the inertia-balance experiment. The experiment may be extended to a study of Stelmholtz resonators, coupled oscillators, electromagnetic forces, thermodynamics and…

  10. Annotated List of Chemistry Laboratory Experiments with Computer Access. Final Report.

    ERIC Educational Resources Information Center

    Bunce, S. C.; And Others

    Project Chemlab was designed to prepare an "Annotated List of Laboratory Experiments in Chemistry from the Journal of Chemical Education (1957-1979)" and to develop a computer file and program to search for specific types of experiments. Provided in this document are listings (photoreduced copies of printouts) of over 1500 entries…

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

    ERIC Educational Resources Information Center

    Kaunda, L.; Ball, D.

    1998-01-01

    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…

  12. Designing a Valuable Freshman Laboratory Experience for the "Average" Science Major

    ERIC Educational Resources Information Center

    Mellon, E. K.

    1977-01-01

    Discusses a teaching program for introductory chemistry laboratories that allows for differences in student background and ability. The flexible program involves self-pacing and a classification of experiments; this permits slower students to proceed through remedial loops while advanced students proceed to more difficult experiments. (MLH)

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

    ERIC Educational Resources Information Center

    Duxbury, Mark

    2004-01-01

    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…

  14. An Undergraduate Biochemistry Laboratory Course with an Emphasis on a Research Experience

    ERIC Educational Resources Information Center

    Caspers, Mary Lou; Roberts-Kirchhoff, Elizabeth S.

    2003-01-01

    In their junior or senior year, biochemistry majors at the University of Detroit Mercy are required to take a two-credit biochemistry laboratory course. Five years ago, the format of this course was changed from structured experiments to a more project-based approach. Several structured experiments were included at the beginning of the course…

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

    ERIC Educational Resources Information Center

    Brunauer, Linda S.; Davis, Kathryn K.

    2008-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2008-01-01

    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…

  18. The Synthesis of 4,6,8-Trimethylazulene: An Organic Laboratory Experiment.

    ERIC Educational Resources Information Center

    Garst, Michael E.; And Others

    1983-01-01

    A two-stage synthesis of 4,6,8-trimethylazulene was developed for use in the undergraduate experiment, highlighting concepts not usually covered in the laboratory. The experiment requires purification procedures of chromatography and of sublimation and illustrates concepts of aromaticity, molecular orbital theory, and carbodium ion reactivity. (JN)

  19. Advanced Undergraduate-Laboratory Experiment on Electron Spin Resonance in Single-Crystal Ruby

    ERIC Educational Resources Information Center

    Collins, Lee A.; And Others

    1974-01-01

    An electron-spin-resonance experiment which has been successfully performed in an advanced undergraduate physics laboratory is described. A discussion of that part of the theory of magnetic resonance necessary for the understanding of the experiment is also provided in this article. (DT)

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

    ERIC Educational Resources Information Center

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

    2005-01-01

    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.

  1. What's New in the Launching of Start-Ups? Features and Implications of Laboratory Experiments

    ERIC Educational Resources Information Center

    Matricano, Diego

    2009-01-01

    This article responds to "Laboratory experiments as a tool in the empirical economic analysis of high-expectation start-ups" by Martin Curley and Piero Formica, published in the December 2008 issue of "Industry and Higher Education." The exploitation of knowledge and experience is increasingly important to companies operating in the globalized…

  2. Discovering Inexpensive, Effective Catalysts for Solar Energy Conversion: An Authentic Research Laboratory Experience

    ERIC Educational Resources Information Center

    Shaner, Sarah E.; Hooker, Paul D.; Nickel, Anne-Marie; Leichtfuss, Amanda R.; Adams, Carissa S.; de la Cerda, Dionisia; She, Yuqi; Gerken, James B.; Pokhrel, Ravi; Ambrose, Nicholas J.; Khaliqi, David; Stahl, Shannon S.; Schuttlefield Christus, Jennifer D.

    2016-01-01

    Electrochemical water oxidation is a major focus of solar energy conversion efforts. A new laboratory experiment has been developed that utilizes real-time, hands-on research to discover catalysts for solar energy conversion. The HARPOON, or Heterogeneous Anodes Rapidly Perused for Oxygen Overpotential Neutralization, experiment allows an array of…

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

    ERIC Educational Resources Information Center

    Ewing, Galen W., Ed.

    1978-01-01

    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)

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

    ERIC Educational Resources Information Center

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

    2006-01-01

    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…

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

    ERIC Educational Resources Information Center

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

    2008-01-01

    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…

  6. BASIC and the Density of Glass. A First-Year Laboratory/Computer Experiment.

    ERIC Educational Resources Information Center

    Harris, Arlo D.

    1986-01-01

    Describes a first-year chemistry laboratory experiment which uses a simple computer program written in BASIC, to analyze data collected by students about the density of a set of marbles. A listing of the program is provided, along with a sample printout of the experiment's results. (TW)

  7. Computation of Chemical Shifts for Paramagnetic Molecules: A Laboratory Experiment for the Undergraduate Curriculum

    ERIC Educational Resources Information Center

    Pritchard, Benjamin P.; Simpson, Scott; Zurek, Eva; Autschbach, Jochen

    2014-01-01

    A computational experiment investigating the [superscript 1]H and [superscript 13]C nuclear magnetic resonance (NMR) chemical shifts of molecules with unpaired electrons has been developed and implemented. This experiment is appropriate for an upper-level undergraduate laboratory course in computational, physical, or inorganic chemistry. The…

  8. Physical barriers formed from gelling liquids: 1. numerical design of laboratory and field experiments

    SciTech Connect

    Finsterle, S.; Moridis, G.J.; Pruess, K.; Persoff, P.

    1994-01-01

    The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface.

  9. A self-novelty manipulation of self-focused attention for internet and laboratory experiments.

    PubMed

    Silvia, Paul J; Eichstaedt, Jan

    2004-05-01

    Conventional manipulations of self-focused attention are poorly suited for Internet experiments and for group-based administration. The authors present a self-novelty manipulation that effectively induces self-awareness for such contexts. In the high self-focus condition, people write about how they differ from their family and friends and from people in general. In the control conditions, people write about neutral topics or do no writing. Three experiments using different measures of self-focus (the situational self-awareness scale, a pronoun selection task, and the private self-consciousness scale) showed that the self-novelty manipulation significantly increased self-focused attention. This effect appeared in Internet-based experiments (Experiment 1) and in laboratory experiments with groups (Experiments 2 and 3). The self-novelty manipulation appears promising for self-awareness research conducted outside of conventional laboratory contexts.

  10. Anti-Collision Function Design and Performances of the CNES Formation Flying Experiment on the PRISMA Mission

    NASA Technical Reports Server (NTRS)

    Cayeux, P.; Raballand, F.; Borde, J.; Berges, J.-C.; Meyssignac, B.

    2007-01-01

    Within the framework of a partnership agreement, EADS ASTRIUM has worked since June 2006 for the CNES formation flying experiment on the PRISMA mission. EADS ASTRIUM is responsible for the anti-collision function. This responsibility covers the design and the development of the function as a Matlab/Simulink library, as well as its functional validation and performance assessment. PRISMA is a technology in-orbit testbed mission from the Swedish National Space Board, mainly devoted to formation flying demonstration. PRISMA is made of two micro-satellites that will be launched in 2009 on a quasi-circular SSO at about 700 km of altitude. The CNES FFIORD experiment embedded on PRISMA aims at flight validating an FFRF sensor designed for formation control, and assessing its performances, in preparation to future formation flying missions such as Simbol X; FFIORD aims as well at validating various typical autonomous rendezvous and formation guidance and control algorithms. This paper presents the principles of the collision avoidance function developed by EADS ASTRIUM for FFIORD; three kinds of maneuvers were implemented and are presented in this paper with their performances.

  11. Dark matter search in the Fréjus Underground Laboratory EDELWEISS experiment

    NASA Astrophysics Data System (ADS)

    de Bellefon, A.; Bergé, L.; Berkès, I.; Broszkiewicz, D.; Chambon, B.; Chapellier, M.; Chardin, G.; Charvin, Ph.; Chazal, V.; Coron, N.; de Jesus, M.; Drain, D.; Dumoulin, L.; Giraud-Héraud, Y.; Guerrier, G.; Goldbach, C.; Hadjout, J. P.; Leblanc, J.; Messous, Y.; Navick, X. F.; Nollez, G.; Pastor, C.; Pari, P.; Prostakov, I.; Perillo-Isaac, M. C.; Yvon, D.

    1996-02-01

    The status of the EDELWEISS experiment (Experience pour DEtecter Les Wimps En SIte Souterrain) in the Fréjus Underground Laboratory is reported. The cryostat is described with the main lines of low radioactivity design and readout system. The first results using bolometer detectors together with the measurement of the internal radioactive background using a 100 cm3 classical Ge crystal are reported. The future program of the experiment will be outlined.

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

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

    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.

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

    SciTech Connect

    Neary, Vincent S

    2011-01-01

    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.

  14. Determination of collision rates relevant to Weibel-like instability growth rates in classical and non-classical plasmas encountered in fast-ignition experiments

    SciTech Connect

    Hill, J M; Key, M H

    2004-10-18

    Analytical simulations of fast-electron currents induced by high-density laser-plasma interactions require estimation of various plasma and beam parameters, including temperatures, densities, and collision rates. This note describes a technique used to estimate or calculate these parameters for the case of contemporary multi-terawatt experiments using foil targets as well as for anticipated fast-ignition-scale experiments.

  15. Undergraduate Laboratory Experiment Facilitating Active Learning of Concepts in Transport Phenomena: Experiment with a Subliming Solid

    ERIC Educational Resources Information Center

    Utgikar, Vivek P.

    2015-01-01

    An experiment based on the sublimation of a solid was introduced in the undergraduate Transport Phenomena course. The experiment required the students to devise their own apparatus and measurement techniques. The theoretical basis, assignment of the experiment, experimental results, and student/instructor observations are described in this paper.…

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

    PubMed Central

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

    2013-01-01

    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

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

    PubMed

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

    2013-11-12

    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.

  18. Will Allis Prize for the Study of Ionized Gases: Electron Collisions - Experiment, Theory, and Applications

    NASA Astrophysics Data System (ADS)

    Bartschat, Klaus

    2016-09-01

    Electron collisions with atoms, ions, and molecules represent one of the very early topics of quantum mechanics. In spite of the field's maturity, a number of recent developments in detector technology (e.g., the ``reaction microscope'' or the ``magnetic-angle changer'') and the rapid increase in computational resources have resulted in significant progress in the measurement, understanding, and theoretical/computational description of few-body Coulomb problems. Close collaborations between experimentalists and theorists worldwide continue to produce high-quality benchmark data, which allow for thoroughly testing and further developing a variety of theoretical approaches. As a result, it has now become possible to reliably calculate the vast amount of atomic data needed for detailed modelling of the physics and chemistry of planetary atmospheres, the interpretation of astrophysical data, optimizing the energy transport in reactive plasmas, and many other topics - including light-driven processes, in which electrons are produced by continuous or short-pulse ultra-intense electromagnetic radiation. I will highlight some of the recent developments that have had a major impact on the field. This will be followed by showcasing examples, in which accurate electron collision data enabled applications in fields beyond traditional AMO physics. Finally, open problems and challenges for the future will be outlined. I am very grateful for fruitful scientific collaborations with many colleagues, and the long-term financial support by the NSF through the Theoretical AMO and Computational Physics programs, as well as supercomputer resources through TeraGrid and XSEDE.

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

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    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.

  20. Simulated and Virtual Science Laboratory Experiments: Improving Critical Thinking and Higher-Order Learning Skills

    NASA Astrophysics Data System (ADS)

    Simon, Nicole A.

    Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory experience, linking with educational technologies (Pyatt & Sims, 2007; 2011; Trundle & Bell, 2010). A causal-comparative quantitative study was conducted with 150 learners enrolled at a two-year community college, to determine the effects of simulation laboratory experiments on Higher-Order Learning, Critical Thinking Skills, and Cognitive Load. The treatment population used simulated experiments, while the non-treatment sections performed traditional expository experiments. A comparison was made using the Revised Two-Factor Study Process survey, Motivated Strategies for Learning Questionnaire, and the Scientific Attitude Inventory survey, using a Repeated Measures ANOVA test for treatment or non-treatment. A main effect of simulated laboratory experiments was found for both Higher-Order Learning, [F (1, 148) = 30.32,p = 0.00, eta2 = 0.12] and Critical Thinking Skills, [F (1, 148) = 14.64,p = 0.00, eta 2 = 0.17] such that simulations showed greater increases than traditional experiments. Post-lab treatment group self-reports indicated increased marginal means (+4.86) in Higher-Order Learning and Critical Thinking Skills, compared to the non-treatment group (+4.71). Simulations also improved the scientific skills and mastery of basic scientific subject matter. It is recommended that additional research recognize that learners' Critical Thinking Skills change due to different instructional methodologies that occur throughout a semester.

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

    PubMed Central

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

    1988-01-01

    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.

  2. An updated study of the O+ - O collision frequency using corresponding FPI and ISR thermospheric wind experiments at Millstone Hill.

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Lima, A. J.; Holt, J. M.; Noto, J.

    2015-12-01

    O+-O collision frequency is an important aeronomic parameter associated with upper atmospheric momentum and energy exchanges between O+ and O. In an analysis of Fabry-Perot Interferometer (FPI) and Incoherent Scatter Radar (ISR) data, Burnside [1987] suggested a modification factor (1.7) to the traditional value of O+-O collision frequency. Determining more accurately the Burnside Factor has been the subject for many prior studies with different techniques. This study revisits the Burnside Factor by using an extended FPI and ISR dataset from Millstone Hill. The FPI data used are from an updated high-resolution instrument, which began operation in 2009. The study included data from 95 nights between 2010 and 2015 when the FPI and ISR (with both zenith and steerable antennas) were all operating. Nights with high Ap were excluded, leaving 1235 data points in total. The same frequentist approach applied previously in Buonsanto et al. [1997] (using 21 experiments) yields similar right-skewed Burnside Factor distribution on this data. In this study we will discuss results derived using different statistical approaches, including median, mean, and the Bayes theorem. The latter method appears to give an estimated median well below 1.0.

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

    SciTech Connect

    Stephen L. Karner, Ph.D

    2006-06-01

    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.

  4. LABORATORY EXPERIMENTS, NUMERICAL SIMULATIONS, AND ASTRONOMICAL OBSERVATIONS OF DEFLECTED SUPERSONIC JETS: APPLICATION TO HH 110

    SciTech Connect

    Hartigan, P.; Carver, R.; Foster, J. M.; Rosen, P. A.; Williams, R. J. R.; Wilde, B. H.; Coker, R. F.; Hansen, J. F.; Blue, B. E.; Frank, A.

    2009-11-01

    Collimated supersonic flows in laboratory experiments behave in a similar manner to astrophysical jets provided that radiation, viscosity, and thermal conductivity are unimportant in the laboratory jets and that the experimental and astrophysical jets share similar dimensionless parameters such as the Mach number and the ratio of the density between the jet and the ambient medium. When these conditions apply, laboratory jets provide a means to study their astrophysical counterparts for a variety of initial conditions, arbitrary viewing angles, and different times, attributes especially helpful for interpreting astronomical images where the viewing angle and initial conditions are fixed and the time domain is limited. Experiments are also a powerful way to test numerical fluid codes in a parameter range in which the codes must perform well. In this paper, we combine images from a series of laboratory experiments of deflected supersonic jets with numerical simulations and new spectral observations of an astrophysical example, the young stellar jet HH 110. The experiments provide key insights into how deflected jets evolve in three dimensions, particularly within working surfaces where multiple subsonic shells and filaments form, and along the interface where shocked jet material penetrates into and destroys the obstacle along its path. The experiments also underscore the importance of the viewing angle in determining what an observer will see. The simulations match the experiments so well that we can use the simulated velocity maps to compare the dynamics in the experiment with those implied by the astronomical spectra. The experiments support a model where the observed shock structures in HH 110 form as a result of a pulsed driving source rather than from weak shocks that may arise in the supersonic shear layer between the Mach disk and bow shock of the jet's working surface.

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

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

    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.

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

    ERIC Educational Resources Information Center

    Armenta, Sergio; de la Guardia, Miguel

    2011-01-01

    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…

  7. Liquid-Liquid Extraction of Insecticides from Juice: An Analytical Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Radford, Samantha A.; Hunter, Ronald E., Jr.; Barr, Dana Boyd; Ryan, P. Barry

    2013-01-01

    A laboratory experiment was developed to target analytical chemistry students and to teach them about insecticides in food, sample extraction, and cleanup. Micro concentrations (sub-microgram/mL levels) of 12 insecticides spiked into apple juice samples are extracted using liquid-liquid extraction and cleaned up using either a primary-secondary…

  8. Field versus laboratory experiments to evaluate the fate of azoxystrobin in an amended vineyard soil.

    PubMed

    Herrero-Hernández, E; Marín-Benito, J M; Andrades, M S; Sánchez-Martín, M J; Rodríguez-Cruz, M S

    2015-11-01

    This study reports the effect that adding spent mushroom substrate (SMS) to a representative vineyard soil from La Rioja region (Spain) has on the behaviour of azoxystrobin in two different environmental scenarios. Field dissipation experiments were conducted on experimental plots amended at rates of 50 and 150 t ha(-1), and similar dissipation experiments were simultaneously conducted in the laboratory to identify differences under controlled conditions. Azoxystrobin dissipation followed biphasic kinetics in both scenarios, although the initial dissipation phase was much faster in the field than in the laboratory experiments, and the half-life (DT50) values obtained in the two experiments were 0.34-46.3 days and 89.2-148 days, respectively. Fungicide residues in the soil profile increased in the SMS amended soil and they were much higher in the top two layers (0-20 cm) than in deeper layers. The persistence of fungicide in the soil profile is consistent with changes in azoxystrobin adsorption by unamended and amended soils over time. Changes in the dehydrogenase activity (DHA) of soils under different treatments assayed in the field and in the laboratory indicated that SMS and the fungicide had a stimulatory effect on soil DHA. The results reveal that the laboratory studies usually reported in the literature to explain the fate of pesticides in amended soils are insufficient to explain azoxystrobin behaviour under real conditions. Field studies are necessary to set up efficient applications of SMS and fungicide, with a view to preventing the possible risk of water contamination.

  9. Laboratory Experiment Investigating the Impact of Ocean Acidification on Calcareous Organisms

    ERIC Educational Resources Information Center

    Perera, Alokya P.; Bopegedera, A. M. R. P.

    2014-01-01

    The increase in ocean acidity since preindustrial times may have deleterious consequences for marine organisms, particularly those with calcareous structures. We present a laboratory experiment to investigate this impact with general, introductory, environmental, and nonmajors chemistry students. For simplicity and homogeneity, calcite was…

  10. Solubility and Solubility Product Determination of a Sparingly Soluble Salt: A First-Level Laboratory Experiment

    ERIC Educational Resources Information Center

    Bonomo, Raffaele P.; Tabbi, Giovanni; Vagliasindi, Laura I.

    2012-01-01

    A simple experiment was devised to let students determine the solubility and solubility product, "K"[subscript sp], of calcium sulfate dihydrate in a first-level laboratory. The students experimentally work on an intriguing equilibrium law: the constancy of the product of the ion concentrations of a sparingly soluble salt. The determination of…

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

    ERIC Educational Resources Information Center

    Burum, Alex D.; Splittgerber, Allan G.

    2008-01-01

    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…

  12. A Stopped-Flow Kinetics Experiment for the Physical Chemistry Laboratory Using Noncorrosive Reagents

    ERIC Educational Resources Information Center

    Prigodich, Richard V.

    2014-01-01

    Stopped-flow kinetics techniques are important to the study of rapid chemical and biochemical reactions. Incorporation of a stopped-flow kinetics experiment into the physical chemistry laboratory curriculum would therefore be an instructive addition. However, the usual reactions studied in such exercises employ a corrosive reagent that can over…

  13. X-Ray Diffraction of Intermetallic Compounds: A Physical Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Varberg, Thomas D.; Skakuj, Kacper

    2015-01-01

    Here we describe an experiment for the undergraduate physical chemistry laboratory in which students synthesize the intermetallic compounds AlNi and AlNi3 and study them by X-ray diffractometry. The compounds are synthesized in a simple one-step reaction occurring in the solid state. Powder X-ray diffractograms are recorded for the two compounds…

  14. Measurement of the Compressibility Factor of Gases: A Physical Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Varberg, Thomas D.; Bendelsmith, Andrew J.; Kuwata, Keith T.

    2011-01-01

    In this article, we describe an experiment for the undergraduate physical chemistry laboratory in which students measure the compressibility factor of two gases, helium and carbon dioxide, as a function of pressure at constant temperature. The experimental apparatus is relatively inexpensive to construct and is described and diagrammed in detail.…

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

    ERIC Educational Resources Information Center

    Valley Springs School District 2, AR.

    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…

  16. Reform in a General Chemistry Laboratory: How Do Students Experience Change in the Instructional Approach?

    ERIC Educational Resources Information Center

    Chopra, I.; O'Connor, J.; Pancho, R.; Chrzanowski, M.; Sandi-Urena, S.

    2017-01-01

    This qualitative study investigated the experience of a cohort of students exposed consecutively to two substantially different environments in their General Chemistry Laboratory programme. To this end, the first semester in a traditional expository programme was followed by a semester in a cooperative, problem-based, multi-week format. The focus…

  17. The Quartz-Crystal Microbalance in an Undergraduate Laboratory Experiment: Measuring Mass

    ERIC Educational Resources Information Center

    Tsionsky, Vladimir

    2007-01-01

    The study explains the quartz-crystal microbalance (QCM) technique, which is often used as an undergraduate laboratory experiment for measuring the mass of a system. QCM can be used as a mass sensor only when the measured mass is rigidly attached to the surface.

  18. Evaluation of the Persistent Issues in History Laboratory for Virtual Field Experience (PIH-LVFE)

    ERIC Educational Resources Information Center

    Brush, Thomas; Saye, John; Kale, Ugur; Hur, Jung Won; Kohlmeier, Jada; Yerasimou, Theano; Guo, Lijiang; Symonette, Simone

    2009-01-01

    The Persistent Issues in History Laboratory for Virtual Field Experience (PIH-LVFE) combines a database of video cases of authentic classroom practices with multiple resources and tools to enable pre-service social studies teachers to virtually observe teachers implementing problem-based learning activities. In this paper, we present the results…

  19. A Laboratory Experience for Students of Differential Equations using RLC Circuits.

    ERIC Educational Resources Information Center

    Graham, Jeff; Barnes, Julia

    1997-01-01

    Argues that although differential equations are billed as applied mathematics, there is rarely any hands-on experience incorporated into the course. Presents a laboratory project that requires students to obtain data from a physics lab and use that data to compute the coefficients of the second order differential equation, which mathematically…

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

    ERIC Educational Resources Information Center

    Green, Thomas K.; Lane, Charles A.

    2006-01-01

    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…

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

    ERIC Educational Resources Information Center

    Schepmann, Hala G.; Mynderse, Michelle

    2010-01-01

    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…

  2. Thermodynamics of Sodium Dodecyl Sulfate (SDS) Micellization: An Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Marcolongo, Juan P.; Mirenda, Martin

    2011-01-01

    An undergraduate laboratory experiment is presented that allows a thermodynamic characterization of micelle formation of sodium dodecyl sulfate (SDS) in aqueous solutions. The critical micelle concentration (CMC) and the degree of micelle ionization (alpha) are obtained at different temperatures by conductimetry. The molar standard free energy…

  3. Gravimetric Analysis of Bismuth in Bismuth Subsalicylate Tablets: A Versatile Quantitative Experiment for Undergraduate Laboratories

    ERIC Educational Resources Information Center

    Davis, Eric; Cheung, Ken; Pauls, Steve; Dick, Jonathan; Roth, Elijah; Zalewski, Nicole; Veldhuizen, Christopher; Coeler, Joel

    2015-01-01

    In this laboratory experiment, lower- and upper-division students dissolved bismuth subsalicylate tablets in acid and precipitated the resultant Bi[superscript 3+] in solution with sodium phosphate for a gravimetric determination of bismuth subsalicylate in the tablets. With a labeled concentration of 262 mg/tablet, the combined data from three…

  4. Two Experiments on Laboratory-Induced Motion Sickness. I. Acupressure. II. Repeated Exposure.

    DTIC Science & Technology

    1982-12-10

    capabilities. Experiment I is a pilot study investigating the effectiveness of an acupressure method to prevent laboratory induced motion sickness...that the acupressure treatment as applied in this study to a group of airsick referrals was not effective in altering the signs and symptoms of

  5. Feasibility of Practical Laboratory Experiences: Report I. GEM Bulletin 69-4.

    ERIC Educational Resources Information Center

    Ayers, Jerry B.

    An investigation was conducted to determine the feasibility of providing laboratory and internship experience for students enrolled in the Georgia Model program for the preparation of elementary teachers as specified in the final report of the Georgia Educational Model program (ED 025 491). Specifications require each student to complete five…

  6. Design Your Own Workup: A Guided-Inquiry Experiment for Introductory Organic Laboratory Courses

    ERIC Educational Resources Information Center

    Mistry, Nimesh; Fitzpatrick, Christopher; Gorman, Stephen

    2016-01-01

    A guided-inquiry experiment was designed and implemented in an introductory organic chemistry laboratory course. Students were given a mixture of compounds and had to isolate two of the components by designing a viable workup procedure using liquid-liquid separation methods. Students were given the opportunity to apply their knowledge of chemical…

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

    ERIC Educational Resources Information Center

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

    1979-01-01

    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)

  8. Development of a Web-Enabled Learning Platform for Geospatial Laboratories: Improving the Undergraduate Learning Experience

    ERIC Educational Resources Information Center

    Mui, Amy B.; Nelson, Sarah; Huang, Bruce; He, Yuhong; Wilson, Kathi

    2015-01-01

    This paper describes a web-enabled learning platform providing remote access to geospatial software that extends the learning experience outside of the laboratory setting. The platform was piloted in two undergraduate courses, and includes a software server, a data server, and remote student users. The platform was designed to improve the quality…

  9. Analyzing Exonuclease-Induced Hyperchromicity by Uv Spectroscopy: An Undergraduate Biochemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Ackerman, Megan M.; Ricciardi, Christopher; Weiss, David; Chant, Alan; Kraemer-Chant, Christina M.

    2016-01-01

    An undergraduate biochemistry laboratory experiment is described that utilizes free online bioinformatics tools along with readily available exonucleases to study the effects of base stacking and hydrogen bonding on the UV absorbance of DNA samples. UV absorbance of double-stranded DNA at the ?[subscript max] is decreased when the DNA bases are…

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

    ERIC Educational Resources Information Center

    Rice, Charles V.; Giffin, Guinevere A.

    2008-01-01

    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;…

  11. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    ERIC Educational Resources Information Center

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

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

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  13. Dehydration of 2-Methyl-1-Cyclohexanol: New Findings from a Popular Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Friesen, J. Brent; Schretzman, Robert

    2011-01-01

    The mineral acid-catalyzed dehydration of 2-methyl-1-cyclohexanol has been a popular laboratory exercise in second-year organic chemistry for several decades. The dehydration experiment is often performed by organic chemistry students to illustrate Zaitsev's rule. However, sensitive analytical techniques reveal that the results do not entirely…

  14. Designing Experiments on Thermal Interactions by Secondary-School Students in a Simulated Laboratory Environment

    ERIC Educational Resources Information Center

    Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides

    2011-01-01

    Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample: Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and…

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

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

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

    ERIC Educational Resources Information Center

    Splittgerber, A. G.; Sohl, Julie

    1988-01-01

    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)

  17. A Student Laboratory Experiment Based on the Vitamin C Clock Reaction

    ERIC Educational Resources Information Center

    Vitz, Ed

    2007-01-01

    The Vitamin C Clock Reaction has now been adapted to serve as a student laboratory experiment in the education process of high-school and college-level general chemistry. Despite of imparting valuable knowledge, it also may be hazardous, as the tincture of iodine contains inflammable substances that may cause burning on prolonged exposure.

  18. Laboratory and in-flight experiments to evaluate 3-D audio display technology

    NASA Technical Reports Server (NTRS)

    Ericson, Mark; Mckinley, Richard; Kibbe, Marion; Francis, Daniel

    1994-01-01

    Laboratory and in-flight experiments were conducted to evaluate 3-D audio display technology for cockpit applications. A 3-D audio display generator was developed which digitally encodes naturally occurring direction information onto any audio signal and presents the binaural sound over headphones. The acoustic image is stabilized for head movement by use of an electromagnetic head-tracking device. In the laboratory, a 3-D audio display generator was used to spatially separate competing speech messages to improve the intelligibility of each message. Up to a 25 percent improvement in intelligibility was measured for spatially separated speech at high ambient noise levels (115 dB SPL). During the in-flight experiments, pilots reported that spatial separation of speech communications provided a noticeable improvement in intelligibility. The use of 3-D audio for target acquisition was also investigated. In the laboratory, 3-D audio enabled the acquisition of visual targets in about two seconds average response time at 17 degrees accuracy. During the in-flight experiments, pilots correctly identified ground targets 50, 75, and 100 percent of the time at separation angles of 12, 20, and 35 degrees, respectively. In general, pilot performance in the field with the 3-D audio display generator was as expected, based on data from laboratory experiments.

  19. Transitioning from Expository Laboratory Experiments to Course-Based Undergraduate Research in General Chemistry

    ERIC Educational Resources Information Center

    Clark, Ted M.; Ricciardo, Rebecca; Weaver, Tyler

    2016-01-01

    General chemistry courses predominantly use expository experiments that shape student expectations of what a laboratory activity entails. Shifting within a semester to course-based undergraduate research activities that include greater decision-making, collaborative work, and "messy" real-world data necessitates a change in student…

  20. An Advanced Undergraduate Chemistry Laboratory Experiment Exploring NIR Spectroscopy and Chemometrics

    ERIC Educational Resources Information Center

    Wanke, Randall; Stauffer, Jennifer

    2007-01-01

    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.

  1. Nitration of Phenols Using Cu(NO[subscript 3])[subscript 2]: Green Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Yadav, Urvashi; Mande, Hemant; Ghalsasi, Prasanna

    2012-01-01

    An easy-to-complete, microwave-assisted, green chemistry, electrophilic nitration method for phenol using Cu(NO[subscript 3])[subscript 2] in acetic acid is discussed. With this experiment, students clearly understand the mechanism underlying the nitration reaction in one laboratory session. (Contains 4 schemes.)

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

    ERIC Educational Resources Information Center

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

    2014-01-01

    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…

  3. TNSA-like plasmas collision in an ambient magnetic field as a route to astrophysical collisionless shock observation in a laboratory

    NASA Astrophysics Data System (ADS)

    Korneev, Ph.; D'Humières, E.; Tikhonchuk, V.; Higginson, D. P.; Fuchs, J.

    2015-12-01

    Plasma collisions in magnetic fields play an important role in the acceleration of particles and radiation generation in astrophysical objects and in the high intensity laser plasma interaction. In laser-target interaction the expanding plasmas can be created with the Target Normal Sheath Acceleration mechanism, TNSA. The possibility to observe the Weibel filamentation in two inter-penetrating TNSA plasmas in an ambient magnetic field is studied theoretically and numerically in the present work. Relying on 2D3V Particle-In-Cell simulations and analytical estimates, the effect of the decreasing density profile coupled to the increasing flow velocity on the external magnetic field accumulation and the development of the magnetic vortexes is analyzed. It is demonstrated that with realistic TNSA profiles the plasma collision can lead to magnetic field accumulation and to the development of magnetic vortexes. These results are of interest for interpretation of the experiments which may be carried out in this regime on high intensity laser facilities.

  4. Dirac bubble potential for He-He and inadequacies in the continuum: Comparing an analytic model with elastic collision experiments.

    PubMed

    Chrysos, Michael

    2017-01-14

    We focus on the long-pending issue of the inadequacy of the Dirac bubble potential model in the description of He-He interactions in the continuum [L. L. Lohr and S. M. Blinder, Int. J. Quantum Chem. 53, 413 (1995)]. We attribute this failure to the lack of a potential wall to mimic the onset of the repulsive interaction at close range separations. This observation offers the explanation to why this excessively simple model proves incapable of quantitatively reproducing previous experimental findings of glory scattering in He-He, although being notorious for its capability of reproducing several distinctive features of the atomic and isotopic helium dimers and trimers [L. L. Lohr and S. M. Blinder, Int. J. Quantum Chem. 90, 419 (2002)]. Here, we show that an infinitely high, energy-dependent potential wall of properly calculated thickness rc(E) taken as a supplement to the Dirac bubble potential suffices for agreement with variable-energy elastic collision cross section experiments for (4)He-(4)He, (3)He-(4)He, and (3)He-(3)He [R. Feltgen et al., J. Chem. Phys. 76, 2360 (1982)]. In the very low energy regime, consistency is found between the Dirac bubble potential (to which our extended model is shown to reduce) and cold collision experiments [J. C. Mester et al., Phys. Rev. Lett. 71, 1343 (1993)]; this consistency, which in this regime lends credence to the Dirac bubble potential, was never noticed by its authors. The revised model being still analytic is of high didactical value while expected to increase in predictive power relative to other appraisals.

  5. Fostering expert inquiry skills and beliefs about chemistry through the MORE laboratory experience

    NASA Astrophysics Data System (ADS)

    Tien, Lydia Tsing

    Typical college science instruction fails to promote an accurate view of science as a discipline and a practice. This is likely due to the fact that the experiences of students in the classroom are very different from the actions and thought processes of scientists. Thus, students often leave the classroom experience with poor inquiry skills and naive beliefs about scientific practice. In order to bridge the gap between the typical classroom experience and expert practice, the MORE Project laboratory curriculum was developed to accompany the general chemistry course at the University of California at Berkeley. The framework guiding the curriculum development considered findings from educational and cognitive science research. The three components of the framework are: (a) exploration of concepts through authentic scientific inquiry; (b) promotion of metacognition; and (c) support for guided discovery. The curriculum provides students with a cognitive model of expert research, the MORE (Model-Observe-Reflect-Explain) Cycle, to encourage students to explore conceptually-rich systems through authentic research opportunities, such as designing experiments and refining explanatory models. By embedding the MORE structure into the laboratory curriculum, we provide students with a model for how scientists think through the inquiry process. In order to assess the impact of the MORE Project learning environment, it was implemented in two sections concurrent with the traditional laboratory experience. Various instruments were administered to determine any differences between the test and control groups with regards to attitudes towards chemistry, conceptual understanding, inquiry skills, and beliefs about scientific practice. Based on the analyses, students experiencing the MORE classroom achieved significant gains in all areas compared with students enrolled in the more traditional laboratory class. Specifically, students in the MORE class (a) recognized the complex, dynamic

  6. Cross-disciplinary thermoregulation and sweat analysis laboratory experiences for undergraduate Chemistry and Exercise Science students.

    PubMed

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

    2011-06-01

    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 distinct disciplines [chemistry (CHEM) and exercise physiology (EPHE)] combined to study exercise thermoregulation and sweat analysis. Twenty-eight senior BSc Kinesiology (EPHE) students and 42 senior BSc CHEM students participated as part of their mutually exclusive, respective courses. The effectiveness of this laboratory environment was evaluated qualitatively using written comments collected from all students as well as from formal focus groups conducted after the CD laboratory with a representative cohort from each class (n = 16 CHEM students and 9 EPHE students). An open coding strategy was used to analyze the data from written feedback and focus group transcripts. Coding topics were generated and used to develop five themes found to be consistent for both groups of students. These themes reflected the common student perceptions that the CD experience was valuable and that students enjoyed being able to apply academic concepts to practical situations as well as the opportunity to interact with students from another discipline of study. However, students also reported some challenges throughout this experience that stemmed from the combination of laboratory groups from different disciplines with limited modification to the design of the original, pre-CD, learning environments. The results indicate that this laboratory created an effective learning opportunity that fostered student interest and enthusiasm for learning. The findings also provide information that could inform subsequent design and implementation of similar CD experiences to enhance engagement of all students and improve instructor efficacy.

  7. Evidence of an Alternative Currency for Altruism in Laboratory-Based Experiments

    PubMed Central

    Farrelly, Daniel; Moan, Emma; White, Kristi; Young, Sarah

    2015-01-01

    Research shows that altruistic behaviours arise in varying social situations in line with different theories of causes of such behaviours. However most research uses financial costs only, which makes our understanding of altruism currently limited. This study presents findings of three experiments that use a novel and simple laboratory-based task that measures altruism based on the amount of time participants are willing to spend as a cost to help others. This task assessed two specific theories; altruistic punishment (Experiments 1 & 2) and empathy-altruism (Experiment 3). All experiments showed that the task was successful, as participants were more likely to altruistically punish violators of social contracts than other scenarios (Experiments 1 and 2), and also incur more costs to behave altruistically towards others when feeling empathic than different emotional states (Experiment 3). These results provide clear support for the use and value of this novel task in future research. PMID:27247644

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

    NASA Astrophysics Data System (ADS)

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

    2012-10-01

    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

  9. Laboratory experiments on stability and entrainment of oceanic stratocumulus. Part 1: Instability experiment

    NASA Technical Reports Server (NTRS)

    Shy, Shenqyang S.

    1990-01-01

    The existence and persistence of marine stratocumulus play a significant role in the overall energy budget of the earth. Their stability and entrainment process are important in global climate studies, as well as for local weather forecasting. The purposes of the experimental simulations are to study this process and to address this paradox. The effects of buoyancy reversal is investigated, followed by two types of experiments. An instability experiment involves the behavior of a fully turbulent wake near the inversion generated by a sliding plate. Due to buoyancy reversal, the heavy, mixed fluid starts to sink, turning the potential energy created by the mixing process into kinetic energy, thereby increasing the entrainment rate. An entrainment experiment, using a vertically oscillating grid driven by a controllable speed motor, produces many eddy-induced entrainments at a surface region on scales much less than the depth of the layer.

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

    PubMed

    Ratsch, H

    2008-04-01

    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

  11. A simple laboratory experiment to measure the surface tension of a liquid in contact with air

    NASA Astrophysics Data System (ADS)

    Riba, Jordi-Roger; Esteban, Bernat

    2014-09-01

    A simple and accurate laboratory experiment to measure the surface tension of liquids has been developed, which is well suited to teach the behaviour of liquids to first- or second-year students of physics, engineering or chemistry. The experimental setup requires relatively inexpensive equipment usually found in physics and chemistry laboratories, since it consists of a used or recycled burette, an analytical balance and a stereoscopic microscope or a micrometer. Experimental data and error analysis show that the surface tension of distilled water, 1-butanol and glycerol can be determined with accuracy better than 1.4%.

  12. Collisions in outer space produced an icosahedral phase in the Khatyrka meteorite never observed previously in the laboratory.

    PubMed

    Bindi, Luca; Lin, Chaney; Ma, Chi; Steinhardt, Paul J

    2016-12-08

    We report the first occurrence of an icosahedral quasicrystal with composition Al62.0(8)Cu31.2(8)Fe6.8(4), outside the measured equilibrium stability field at standard pressure of the previously reported Al-Cu-Fe quasicrystal (AlxCuyFez, with x between 61 and 64, y between 24 and 26, z between 12 and 13%). The new icosahedral mineral formed naturally and was discovered in the Khatyrka meteorite, a recently described CV3 carbonaceous chondrite that experienced shock metamorphism, local melting (with conditions exceeding 5 GPa and 1,200 °C in some locations), and rapid cooling, all of which likely resulted from impact-induced shock in space. This is the first example of a quasicrystal composition discovered in nature prior to being synthesized in the laboratory. The new composition was found in a grain that has a separate metal assemblage containing icosahedrite (Al63Cu24Fe13), currently the only other known naturally occurring mineral with icosahedral symmetry (though the latter composition had already been observed in the laboratory prior to its discovery in nature). The chemistry of both the icosahedral phases was characterized by electron microprobe, and the rotational symmetry was confirmed by means of electron backscatter diffraction.

  13. Collisions in outer space produced an icosahedral phase in the Khatyrka meteorite never observed previously in the laboratory

    PubMed Central

    Bindi, Luca; Lin, Chaney; Ma, Chi; Steinhardt, Paul J.

    2016-01-01

    We report the first occurrence of an icosahedral quasicrystal with composition Al62.0(8)Cu31.2(8)Fe6.8(4), outside the measured equilibrium stability field at standard pressure of the previously reported Al-Cu-Fe quasicrystal (AlxCuyFez, with x between 61 and 64, y between 24 and 26, z between 12 and 13%). The new icosahedral mineral formed naturally and was discovered in the Khatyrka meteorite, a recently described CV3 carbonaceous chondrite that experienced shock metamorphism, local melting (with conditions exceeding 5 GPa and 1,200 °C in some locations), and rapid cooling, all of which likely resulted from impact-induced shock in space. This is the first example of a quasicrystal composition discovered in nature prior to being synthesized in the laboratory. The new composition was found in a grain that has a separate metal assemblage containing icosahedrite (Al63Cu24Fe13), currently the only other known naturally occurring mineral with icosahedral symmetry (though the latter composition had already been observed in the laboratory prior to its discovery in nature). The chemistry of both the icosahedral phases was characterized by electron microprobe, and the rotational symmetry was confirmed by means of electron backscatter diffraction. PMID:27929519

  14. Collisions in outer space produced an icosahedral phase in the Khatyrka meteorite never observed previously in the laboratory

    NASA Astrophysics Data System (ADS)

    Bindi, Luca; Lin, Chaney; Ma, Chi; Steinhardt, Paul J.

    2016-12-01

    We report the first occurrence of an icosahedral quasicrystal with composition Al62.0(8)Cu31.2(8)Fe6.8(4), outside the measured equilibrium stability field at standard pressure of the previously reported Al-Cu-Fe quasicrystal (AlxCuyFez, with x between 61 and 64, y between 24 and 26, z between 12 and 13%). The new icosahedral mineral formed naturally and was discovered in the Khatyrka meteorite, a recently described CV3 carbonaceous chondrite that experienced shock metamorphism, local melting (with conditions exceeding 5 GPa and 1,200 °C in some locations), and rapid cooling, all of which likely resulted from impact-induced shock in space. This is the first example of a quasicrystal composition discovered in nature prior to being synthesized in the laboratory. The new composition was found in a grain that has a separate metal assemblage containing icosahedrite (Al63Cu24Fe13), currently the only other known naturally occurring mineral with icosahedral symmetry (though the latter composition had already been observed in the laboratory prior to its discovery in nature). The chemistry of both the icosahedral phases was characterized by electron microprobe, and the rotational symmetry was confirmed by means of electron backscatter diffraction.

  15. Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments

    USGS Publications Warehouse

    Cho, H. Jean; Jaffe, Peter R.; Smith, James A.

    1993-01-01

    This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h−1. In the field experiment the water infiltration rate was 0.34 cm h−1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10−4 h−1 for an infiltration rate of 0.076 cm h−1 and 1.4×10−3 h−1 for an infiltration rate of 0.28 cm h−1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10−4 h−1 to 1×10−2 h−1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the soil

  16. Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments

    NASA Astrophysics Data System (ADS)

    Cho, H. Jean; Jaffé, Peter R.; Smith, James A.

    1993-10-01

    This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h-1. In the field experiment the water infiltration rate was 0.34 cm h-1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10-4 h-1 for an infiltration rate of 0.076 cm h-1 and 1.4×10-3 h-1 for an infiltration rate of 0.28 cm h-1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10-4 h-1 to 1×10-2 h-1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the soil matrix was added to the model

  17. Solute and heat transport model of the Henry and hilleke laboratory experiment.

    PubMed

    Langevin, Christian D; Dausman, Alyssa M; Sukop, Michael C

    2010-01-01

    SEAWAT is a coupled version of MODFLOW and MT3DMS designed to simulate variable-density ground water flow and solute transport. The most recent version of SEAWAT, called SEAWAT Version 4, includes new capabilities to represent simultaneous multispecies solute and heat transport. To test the new features in SEAWAT, the laboratory experiment of Henry and Hilleke (1972) was simulated. Henry and Hilleke used warm fresh water to recharge a large sand-filled glass tank. A cold salt water boundary was represented on one side. Adjustable heating pads were used to heat the bottom and left sides of the tank. In the laboratory experiment, Henry and Hilleke observed both salt water and fresh water flow systems separated by a narrow transition zone. After minor tuning of several input parameters with a parameter estimation program, results from the SEAWAT simulation show good agreement with the experiment. SEAWAT results suggest that heat loss to the room was more than expected by Henry and Hilleke, and that multiple thermal convection cells are the likely cause of the widened transition zone near the hot end of the tank. Other computer programs with similar capabilities may benefit from benchmark testing with the Henry and Hilleke laboratory experiment.

  18. Solute and heat transport model of the Henry and Hilleke laboratory experiment

    USGS Publications Warehouse

    Langevin, C.D.; Dausman, A.M.; Sukop, M.C.

    2010-01-01

    SEAWAT is a coupled version of MODFLOW and MT3DMS designed to simulate variable-density ground water flow and solute transport. The most recent version of SEAWAT, called SEAWAT Version 4, includes new capabilities to represent simultaneous multispecies solute and heat transport. To test the new features in SEAWAT, the laboratory experiment of Henry and Hilleke (1972) was simulated. Henry and Hilleke used warm fresh water to recharge a large sand-filled glass tank. A cold salt water boundary was represented on one side. Adjustable heating pads were used to heat the bottom and left sides of the tank. In the laboratory experiment, Henry and Hilleke observed both salt water and fresh water flow systems separated by a narrow transition zone. After minor tuning of several input parameters with a parameter estimation program, results from the SEAWAT simulation show good agreement with the experiment. SEAWAT results suggest that heat loss to the room was more than expected by Henry and Hilleke, and that multiple thermal convection cells are the likely cause of the widened transition zone near the hot end of the tank. Other computer programs with similar capabilities may benefit from benchmark testing with the Henry and Hilleke laboratory experiment. Journal Compilation ?? 2009 National Ground Water Association.

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

    PubMed

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

    2012-09-01

    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.

  20. Using Laboratory Experiments and Circuit Simulation IT Tools in an Undergraduate Course in Analog Electronics

    NASA Astrophysics Data System (ADS)

    Baltzis, Konstantinos B.; Koukias, Konstantinos D.

    2009-12-01

    Laboratory-based courses play a significant role in engineering education. Given the role of electronics in engineering and technology, laboratory experiments and circuit simulation IT tools are used in their teaching in several academic institutions. This paper discusses the characteristics and benefits of both methods. The content and structure of an introductory laboratory course in analog electronics is described. The aim of the course is the better understanding of the basic principles of analog electronic circuits without the need of specific technical and computer skills. The impact of the proposed method on the learning process is investigated. The evaluation of our proposal was based on both quantitative and qualitative data. Interesting conclusions about the teaching of electronics in undergraduate education are finally drawn.

  1. Communication and laboratory performance in parapsychology experiments: demand characteristics and the social organization of interaction.

    PubMed

    Wooffitt, Robin

    2007-09-01

    This paper reports findings from a conversation analytic study of experimenter-participant interaction in parapsychology experiments. It shows how properties of communication through which the routine business of the experiment is conducted may have an impact on the research participant's subsequent performance. In this, the study explores social psychological features of the psychology laboratory. In particular, it examines aspects of Orne's (1962) account of what he called the demand characteristics of the psychological experiment. The data come from a corpus of audio recordings of experimenter-participant interaction during experiments on extra-sensory perception. These kinds of experiments, and the phenomena they purport to study, are undoubtedly controversial; however, the paper argues that there are grounds for social psychologists to consider parapsychology experiments as a class (albeit distinctive) of psychology experiments, and, therefore, as sites in which general social psychological and communicative phenomena can be studied. The empirical sections of the paper examine interaction during part of the experimental procedure when the experimenter verbally reviews a record of the participant's imagery reported during an earlier part of the experiment. The analysis shows that the way in which the experimenter acknowledges the research participants' utterances may be significant for the trajectory of the experiment and explores how the participants' subsequent performance in the experiment may be influenced by interactionally generated contingencies.

  2. Comparisons of laboratory bioassays and a whole-lake experiment: Rotifer responses to experimental acidification

    SciTech Connect

    Gonzalez, M.J.; Frost, T.M. )

    1994-02-01

    The authors test whether data from laboratory bioassays can be used to predict zooplankton responses during a whole-lake experiment using two rotifers, Keratella cochlearis and Keratella taurocephala. The acidification experiment was conducted in Little Rock Lake, Wisconsin, USA, which was divided into a reference basin maintained at a natural pH near 6.1 and a treatment basin which was acidified in 2-yr stages to pH values of 5.6, 5.2, and 4.7. Laboratory assays examined the effect of pH on reproduction under varied food conditions and survivorship without food. In the lake, the two rotifers showed strong and opposite responses to acidification: K. cochlearis decreased in abundance while K. taurocephala increased. In the laboratory bioassays, neither species was sensitive to pH when food conditions yielded high reproductive rates. When food was limited, K. cochlearis exhibited lower survivorship and a trend towards lower reproductive rates at lower pH. With limited food, K. taurocephala survivorship was either unaffected by pH or higher at high pH and its reproduction was slightly higher at intermediate pH. In situ experiments revealed that food conditions in the treatment basin lowered reproduction by K. cochlearis, indicating that a combined effect of food and pH caused its population decline. Neither food nor pH could explain the increase in K. taurocephala, which appeared to be linked to a reduction in its predators at lower pH. Overall, the analyses revealed substantial discrepancies between laboratory bioassays and in-lake responses. This was particularly the case for K. taurocephala, for which assays predicted no changes or a decline in abundance rather than the marked increase that actually occurred. The results suggest that caution should be used in extending results from laboratory assays to natural ecosystems.

  3. DebriSat - A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterizations

    NASA Technical Reports Server (NTRS)

    Liou, Jer-Chyi; Clark, S.; Fitz-Coy, N.; Huynh, T.; Opiela, J.; Polk, M.; Roebuck, B.; Rushing, R.; Sorge, M.; Werremeyer, M.

    2013-01-01

    The goal of the DebriSat project is to characterize fragments generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 s US Navy Transit satellite. There are three phases to this project: the design and fabrication of DebriSat - an engineering model representing a modern, 60-cm/50-kg class LEO satellite; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area-to-mass ratio, density, shape, material composition, optical properties, and radar cross-section distributions, will be used to supplement the DoD s and NASA s satellite breakup models to better describe the breakup outcome of a modern satellite.

  4. DebriSat- A Planned Laboratory-Based Satellite Impact Experiment for Breakup Fragment Characterization

    NASA Astrophysics Data System (ADS)

    Liou, J.-C.; Clark, S.; Fitz-Coy, N.; Huynh, T.; Opiela, J.; Polk, M.; Roebuck, B.; Rushing, R.; Sorge, M.; Werremeyer, M.

    2013-08-01

    The goal of the DebriSat project is to characterize fragments generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960s U.S. Navy Transit satellite. There are three phases to this project: the design and fabrication of DebriSat - an engineering model representing a modern, 60-cm/50-kg LEO satellite; performance of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area-to-mass ratio, density, shape, material composition, optical properties, and radar cross-section distributions, will be used to supplement the DoD and NASA satellite breakup models to better describe the breakup outcome of a modern satellite.

  5. Apoptosis as the focus of an authentic research experience in a cell physiology laboratory.

    PubMed

    Byrd, Shere K

    2016-06-01

    Curriculum-embedded independent research is a high-impact teaching practice that has been shown to increase student engagement and learning. This article describes a multiweek laboratory project for an upper-division undergraduate cell physiology laboratory using apoptosis via the mitochondrial pathway as the overarching theme. Students did literature research on apoptotic agents that acted via the mitochondrial pathway. Compounds ranged from natural products such as curcumin to synthetic compounds such as etoposide. Groups of two to three students planned a series of experiments using one of three cultured cell lines that required them to 1) learn to culture cells; 2) determine treatment conditions, including apoptotic agent solubility and concentration ranges that had been reported in the literature; 3) choose two methods to validate/quantify apoptotic capacity of the reagent; and 4) attempt to "rescue" cells from undergoing apoptosis using one of several available compounds/methods. In essence, given some reagent and equipment constraints, students designed an independent experiment to highlight the effects of different apoptotic agents on cells in culture. Students presented their experimental designs as in a laboratory group meeting and their final findings as a classroom "symposium." This exercise can be adapted to many different types of laboratories with greater or lesser equipment and instrumentation constraints, incorporates several core cell physiology methods, and encourages key experimental design and critical thinking components of independent research.

  6. Fish physiology and metal pollution: results and experiences from laboratory and field studies

    SciTech Connect

    Larsson, A.; Haux, C.; Sjoebeck, M.L.

    1985-06-01

    Physiological methods, previously used as health indicators in laboratory investigations on fish exposed to toxicants, have been applied to feral fish living in metal-polluted waters. A background to the use of a physiological approach for detecting early-arising effects of toxic chemicals on fish is given, together with a description of the clinical parameters used and their physiological relevance. The results and experiences from the field application show that certain clinical methods may be very useful in detecting and diagnosing sublethal disturbances in natural fish populations in polluted areas. Furthermore, the results indicate a good agreement between metal-induced physiological effects detected in fish exposed under natural field conditions and those found in laboratory experiments.

  7. Laboratory experiments on membrane filter sampling of airborne mycotoxins produced by Stachybotrys atra corda

    NASA Astrophysics Data System (ADS)

    Pasanen, A.-L.; Nikulin, M.; Tuomainen, M.; Berg, S.; Parikka, P.; Hintikka, E.-L.

    A membrane filter method for sampling of airborne stachybotrystoxins was studied in the laboratory. Toxigenic strains of Stachybotrys atra on wallpaper, grain, hay and straw were used as toxin sources in the experiments. Air samples were collected on cellulose nitrate and polycarbonate membrane filters at air flow rates of 10-20 ℓ min -1. After the filter sampling, the air was passed through methanol. The results showed that stachybotrystoxins (trichothecenes) were concentrated in airborne fungal propagules, and thus can be collected on filters. Polycarbonate filters with a pore size of 0.2 μm collected the highest percentage of toxic samples. The laboratory experiments indicated that polycarbonate filter sampling for the collection of airborne mycotoxins is a promising method for extension to field measurements.

  8. A Study of Nuclear effects in Drell-Yan and Charmonia Productions in p-A collisions at Fermilab E906/SeaQuest Experiment

    NASA Astrophysics Data System (ADS)

    Liu, Ming; E906/SeaQuest Collaboration

    2016-09-01

    Strong suppressions of charmonia have been observed in heavy ion collisions at RHIC and LHC. The suppressions exhibit strong nucleus A and kinematic dependences, especially with Feynman-x/rapidity and transverse momentum pT. Such suppression in heavy ion collisions is predicted to be an important signature for the formation of quark-gluon plasma (QGP) due to color screening, however, there are also other non-QGP effects, such as initial state parton energy loss, parton shadowing and final state breakup. It is important to quantify the contributions from the cold nuclear matter, which could be achieved through studying charmonia and Drell-Yan productions in proton-nucleus collisions where no significant QGP is expected. E906/SeaQuest is a fixed-target dimuon experiment at Fermilab using the 120 GeV proton beam from the Main Injector. E906 has been taking high statistic data samples of p+p, p+d, p+C, p+Fe and p+W collisions since 2014 and will continue data taking until the summer of 2017. E906 measures J / ψ ,ψ' and Drell-Yan productions in the dimuon channel in p+p and p+A collisions over a wide range of kinematic coverage, that is optimal for the study of the cold nuclear matter effects. Recently, we released the first preliminary results will be presented.

  9. A model for the three-dimensional spacecraft control laboratory experiment

    NASA Technical Reports Server (NTRS)

    Kakad, Yogendra P.

    1991-01-01

    A model for the three-dimensional Spacecraft Control Laboratory Experiment (SCOLE) is developed. The objective behind this method of modelling is to utilize the basic partial differential equations of motion for this distributed parameter system and not to use the modal expansion in developing the model. The final model obtained is in terms of a transfer function matrix which relates the flexible mast parameters like displacement, slope, shear stress, etc. to external forces and moments.

  10. Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

    DOE PAGES

    Li, C. K.; Tzeferacos, P.; Lamb, D.; ...

    2016-10-07

    X-ray images from the Chandra X-ray Observatory show that the South-East jet in the Crab nebula changes direction every few years. This remarkable phenomenon is also observed in jets associated with pulsar wind nebulae and other astrophysical objects, and therefore is a fundamental feature of astrophysical jet evolution that needs to be understood. Theoretical modeling and numerical simulations have suggested that this phenomenon may be a consequence of magnetic fields (B) and current-driven magnetohydrodynamic (MHD) instabilities taking place in the jet, but until now there has been no verification of this process in a controlled laboratory environment. Here we reportmore » the first such experiments, using scaled laboratory plasma jets generated by high-power lasers to model the Crab jet and monoenergetic-proton radiography to provide direct visualization and measurement of magnetic fields and their behavior. The toroidal magnetic field embedded in the supersonic jet triggered plasma instabilities and resulted in considerable deflections throughout the jet propagation, mimicking the kinks in the Crab jet. We also demonstrated that these kinks are stabilized by high jet velocity, consistent with the observation that instabilities alter the jet orientation but do not disrupt the overall jet structure. We successfully modeled these laboratory experiments with a validated three-dimensional (3D) numerical simulation, which in conjunction with the experiments provide compelling evidence that we have an accurate model of the most important physics of magnetic fields and MHD instabilities in the observed, kinked jet in the Crab nebula. The experiments initiate a novel approach in the laboratory for visualizing fields and instabilities associated with jets observed in various astrophysical objects, ranging from stellar to extragalactic systems. We expect that future work along this line will have important impact on the study and understanding of such fundamental

  11. Copper sulphate reduces the metabolic activity of Gammarus fossarum in laboratory and field experiments.

    PubMed

    Schmidlin, Lara; von Fumetti, Stefanie; Nagel, Peter

    2015-04-01

    The specialised fauna of freshwater springs is affected by contamination of the water with xenobiotics from human activities in the surrounding landscape. We assessed the effects of exposure to toxins in laboratory and field experiments by using copper sulphate as a model substance and Gammarus fossarum Koch, 1836, as the model organism. This amphipod is a common representative of the European spring fauna and copper is a widespread contaminant, mainly from agricultural practice. The experiments were conducted in test chambers placed in flow channels and directly in a spring. The gammarids were fed with conditioned beech leaf discs, which had been exposed to a 0.8 mg Cu/L solution for 96 h. The feeding activity of the amphipods was quantified on the level of the organism; and the respiratory electron transport system (ETS) assay was conducted in order to determine changes on the cellular level in the test organisms. The results show that the feeding activity, when the leaf discs were contaminated with copper, was not significantly different from the control. The ETS activity of the gammarids, which had been feeding on the copper contaminated leaf discs was however significantly reduced. The results followed the same pattern for gammarids from both the laboratory and the spring. By conducting the experiments not only in a laboratory but also directly in a spring in the field, we took a crucial step towards a more realistic approach when examining environmental pollutants on an organism. Our findings demonstrate the importance of conducting experiments out in the field, in natural conditions, as well as in the laboratory.

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

    NASA Technical Reports Server (NTRS)

    1972-01-01

    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.

  13. Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

    SciTech Connect

    Li, C. K.; Tzeferacos, P.; Lamb, D.; Gregori, G.; Norreys, P. A.; Rosenberg, M. J.; Follett, R. K.; Froula, D. H.; Koenig, M.; Seguin, F. H.; Frenje, J. A.; Rinderknecht, H. G.; Sio, H.; Zylstra, A. B.; Petrasso, R. D.; Amendt, P. A.; Park, H. S.; Remington, B. A.; Ryutov, D. D.; Wilks, S. C.; Betti, R.; Frank, A.; Hu, S. X.; Sangster, T. C.; Hartigan, P.; Drake, R. P.; Kuranz, C. C.; Lebedev, S. V.; Woolsey, N. C.

    2016-10-07

    X-ray images from the Chandra X-ray Observatory show that the South-East jet in the Crab nebula changes direction every few years. This remarkable phenomenon is also observed in jets associated with pulsar wind nebulae and other astrophysical objects, and therefore is a fundamental feature of astrophysical jet evolution that needs to be understood. Theoretical modeling and numerical simulations have suggested that this phenomenon may be a consequence of magnetic fields (B) and current-driven magnetohydrodynamic (MHD) instabilities taking place in the jet, but until now there has been no verification of this process in a controlled laboratory environment. Here we report the first such experiments, using scaled laboratory plasma jets generated by high-power lasers to model the Crab jet and monoenergetic-proton radiography to provide direct visualization and measurement of magnetic fields and their behavior. The toroidal magnetic field embedded in the supersonic jet triggered plasma instabilities and resulted in considerable deflections throughout the jet propagation, mimicking the kinks in the Crab jet. We also demonstrated that these kinks are stabilized by high jet velocity, consistent with the observation that instabilities alter the jet orientation but do not disrupt the overall jet structure. We successfully modeled these laboratory experiments with a validated three-dimensional (3D) numerical simulation, which in conjunction with the experiments provide compelling evidence that we have an accurate model of the most important physics of magnetic fields and MHD instabilities in the observed, kinked jet in the Crab nebula. The experiments initiate a novel approach in the laboratory for visualizing fields and instabilities associated with jets observed in various astrophysical objects, ranging from stellar to extragalactic systems. We expect that future work along this line will have important impact on the study and understanding of such fundamental astrophysical

  14. Effect of Biochar on Greenhouse Gas Emissions and Nitrogen Cycling in Laboratory and Field Experiments

    NASA Astrophysics Data System (ADS)

    Hagemann, Nikolas; Harter, Johannes; Kaldamukova, Radina; Ruser, Reiner; Graeff-Hönninger, Simone; Kappler, Andreas; Behrens, Sebastian

    2014-05-01

    The extensive use of nitrogen (N) fertilizers in agriculture is a major source of anthropogenic N2O emissions contributing 8% to global greenhouse gas emissions. Soil biochar amendment has been suggested as a means to reduce both CO2 and non-CO2 greenhouse gas emissions. The reduction of N2O emissions by biochar has been demonstrated repeatedly in field and laboratory experiments. However, the mechanisms of the reduction remain unclear. Further it is not known how biochar field-weathering affects GHG emissions and how agro-chemicals, such as the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP), that is often simultaneously applied together with commercial N-fertilizers, impact nitrogen transformation and N2O emissions from biochar amended soils. In order investigate the duration of the biochar effect on soil N2O emissions and its susceptibility to DMPP application we performed a microcosm and field study with a high-temperature (400 ° C) beech wood derived biochar (60 t ha-1 and 5 % (w/w) biochar in the field and microcosms, respectively). While the field site contained the biochar already for three years, soil and biochar were freshly mixed for the laboratory microcosm experiments. In both studies we quantified GHG emissions and soil nitrogen speciation (nitrate, nitrite, ammonium). While the field study was carried out over the whole vegetation period of the sunflower Helianthus annuus L., soil microcosm experiments were performed for up to 9 days at 28° C. In both experiments a N-fertilizer containing DMPP was applied either before planting of the sunflowers or at the beginning of soil microcosms incubation. Laboratory microcosm experiments were performed at 60% water filled pore space reflecting average field conditions. Our results show that biochar effectively reduced soil N2O emissions by up to 60 % in the field and in the soil microcosm experiments. No significant differences in N2O emission mitigation potential between field-aged and fresh

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

    NASA Astrophysics Data System (ADS)

    Woods, R. O.

    1982-04-01

    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 fow 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.

  16. The LUNA experiment at Gran Sasso Laboratory: Studying stars by going underground

    SciTech Connect

    Guglielmetti, Alessandra

    2015-10-15

    Accurate knowledge of thermonuclear reaction rates is a key issue in nuclear astrophysics: it is important for understanding the energy generation, neutrino production and the synthesis of the elements in stars and during primordial nucleosynthesis. 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 this experiment and on the future perspectives in the field.

  17. Validation experiment of a numerically processed millimeter-wave interferometer in a laboratory.

    PubMed

    Kogi, Y; Higashi, T; Matsukawa, S; Mase, A; Kohagura, J; Nagayama, Y; Kawahata, K; Kuwahara, D; Yoshikawa, M

    2014-11-01

    We propose a new interferometer system for density profile measurements. This system produces multiple measurement chords by a leaky-wave antenna driven by multiple frequency inputs. The proposed system was validated in laboratory evaluation experiments. We confirmed that the interferometer generates a clear image of a Teflon plate as well as the phase shift corresponding to the plate thickness. In another experiment, we confirmed that quasi-optical mirrors can produce multiple measurement chords; however, the finite spot size of the probe beam degrades the sharpness of the resulting image.

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

    NASA Technical Reports Server (NTRS)

    Welch, J. D.

    1975-01-01

    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.

  19. Validation experiment of a numerically processed millimeter-wave interferometer in a laboratory

    SciTech Connect

    Kogi, Y. Higashi, T.; Matsukawa, S.; Mase, A.; Kohagura, J.; Yoshikawa, M.; Nagayama, Y.; Kawahata, K.; Kuwahara, D.

    2014-11-15

    We propose a new interferometer system for density profile measurements. This system produces multiple measurement chords by a leaky-wave antenna driven by multiple frequency inputs. The proposed system was validated in laboratory evaluation experiments. We confirmed that the interferometer generates a clear image of a Teflon plate as well as the phase shift corresponding to the plate thickness. In another experiment, we confirmed that quasi-optical mirrors can produce multiple measurement chords; however, the finite spot size of the probe beam degrades the sharpness of the resulting image.

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

    NASA Astrophysics Data System (ADS)

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

    2000-10-01

    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 (Δ vb = Δ 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.