Science.gov

Sample records for concretos espinelizados in-situ

  1. In situ groundwater bioremediation

    SciTech Connect

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  2. In Situ Cometary Cosmochemistry

    NASA Astrophysics Data System (ADS)

    Wright, I. P.; Andrews, D. J.; Barber, S. J.; Sheridan, S.; Morgan, G. H.; Morse, A. D.

    2013-09-01

    In 2014 the Rosetta space mission arrives at comet 67P. Herein we describe the ambitions of one of the instruments, Ptolemy, included on the lander. Our aim is to make in situ measurements of isotopic compositions of elements such as H, C, N and O.

  3. In Situ Processing.

    ERIC Educational Resources Information Center

    Edgar, T. F.; Schechter, R. S.

    1980-01-01

    Describes research on in situ processing to develop necessary theory and understanding of the underground process to facilitate commercialization of a wide range of mineral deposits. Goal is to produce laboratory and computer-based tools to allow site evaluation based on field and laboratory measurements of mineral and associated overburdens.…

  4. In situ observations

    NASA Astrophysics Data System (ADS)

    Ehhalt, D. H.

    1980-03-01

    To illustrate capabilities and problems of in situ observations, examples of recent measurements are presented which have a bearing on the chlorofluoromethane-ozone problem. These include: (1) resonance fluorescence for the measurement of Cl and ClO, (2) grab and cryogenic collection of whole air samples for the measurement of CFCl3 and CF2Cl2, (3) impregnated filters for acid chloride, and (4) matrix isolation for HO2 and NO2.

  5. In situ reactor

    DOEpatents

    Radtke, Corey William; Blackwelder, David Bradley

    2004-01-27

    An in situ reactor for use in a geological strata, is described and which includes a liner defining a centrally disposed passageway and which is placed in a borehole formed in the geological strata; and a sampling conduit is received within the passageway defined by the liner and which receives a geological specimen which is derived from the geological strata, and wherein the sampling conduit is in fluid communication with the passageway defined by the liner.

  6. In Situ Fabrication Technologies

    NASA Technical Reports Server (NTRS)

    Rolin, Terry D.; Hammond, Monica

    2005-01-01

    A manufacturing system is described that is internal to controlled cabin environments which will produce functional parts to net shape with sufficient tolerance, strength and integrity to meet application specific needs such as CEV ECLS components, robotic arm or rover components, EVA suit items, unforeseen tools, conformal repair patches, and habitat fittings among others. Except for start-up and shut-down, fabrication will be automatic without crew intervention under nominal scenarios. Off-nominal scenarios may require crew and/or Earth control intervention. System will have the ability to fabricate using both provisioned feedstock materials and feedstock refined from in situ regolith.

  7. In Situ Surface Characterization

    NASA Technical Reports Server (NTRS)

    Deen, Robert G.; Leger, Patrick C.; Yanovsky, Igor

    2011-01-01

    Operation of in situ space assets, such as rovers and landers, requires operators to acquire a thorough understanding of the environment surrounding the spacecraft. The following programs help with that understanding by providing higher-level information characterizing the surface, which is not immediately obvious by just looking at the XYZ terrain data. This software suite covers three primary programs: marsuvw, marsrough, and marsslope, and two secondary programs, which together use XYZ data derived from in situ stereo imagery to characterize the surface by determining surface normal, surface roughness, and various aspects of local slope, respectively. These programs all use the Planetary Image Geometry (PIG) library to read mission-specific data files. The programs themselves are completely multimission; all mission dependencies are handled by PIG. The input data consists of images containing XYZ locations as derived by, e.g., marsxyz. The marsuvw program determines surface normals from XYZ data by gathering XYZ points from an area around each pixel and fitting a plane to those points. Outliers are rejected, and various consistency checks are applied. The result shows the orientation of the local surface at each point as a unit vector. The program can be run in two modes: standard, which is typically used for in situ arm work, and slope, which is typically used for rover mobility. The difference is primarily due to optimizations necessary for the larger patch sizes in the slope case. The marsrough program determines surface roughness in a small area around each pixel, which is defined as the maximum peak-to-peak deviation from the plane perpendicular to the surface normal at that pixel. The marsslope program takes a surface normal file as input and derives one of several slope-like outputs from it. The outputs include slope, slope rover direction (a measure of slope radially away from the rover), slope heading, slope magnitude, northerly tilt, and solar energy

  8. In situ measurement system

    DOEpatents

    Lord, D.E.

    1980-11-24

    A multipurpose in situ underground measurement system comprising a plurality of long electrical resistance elements in the form of rigid reinforcing bars, each having an open loop hairpin configuration of shorter length than the other resistance elements. The resistance elements are arranged in pairs in a unitized structure, and grouted in place in the underground volume. Measurement means are provided for obtaining for each pair the electrical resistance of each element and the difference in electrical resistance of the paired elements, which difference values may be used in analytical methods involving resistance as a function of temperature. A scanner means sequentially connects the resistance-measuring apparatus to each individual pair of elements. A source of heating current is also selectively connectable for heating the elements to an initial predetermined temperature prior to electrical resistance measurements when used as an anemometer.

  9. In Situ Nuclear Characterization Infrastructure

    SciTech Connect

    James A. Smith; J. Rory Kennedy

    2011-11-01

    To be able to evolve microstructure with a prescribed in situ process, an effective measurement infrastructure must exist. This interdisciplinary infrastructure needs to be developed in parallel with in situ sensor technology. This paper discusses the essential elements in an effective infrastructure.

  10. Metallographic in situ hybridization.

    PubMed

    Powell, Richard D; Pettay, James D; Powell, William C; Roche, Patrick C; Grogan, Thomas M; Hainfeld, James F; Tubbs, Raymond R

    2007-08-01

    Metallographic methods, in which a target is visualized using a probe or antibody that deposits metal selectively at its binding site, offers many advantages for bright-field in situ hybridization (ISH) detection as well as for other labeling and detection methods. Autometallographically enhanced gold labeling procedures have demonstrated higher sensitivity than conventional enzyme chromogens. Enzyme metallography, a novel procedure in which an enzymatic probe is used to deposit metal directly from solution, has been used to develop bright-field ISH methods for HER2 gene determination in breast cancer and other biopsy specimens. It provides the highest level of sensitivity and resolution, both for visualizing endogenous gene copies in nonamplified tissues and for resolving multiple gene copies to allow copy enumeration in amplified tissues without the need for oil immersion or fluorescence optics. An automated enzyme metallography procedure, silver ISH, has been developed for use in slide-staining instruments. Metallographic staining also provides excellent results for immunohistochemistry and may be combined with other staining procedures for the simultaneous detection of more than one gene or combinations of genes and proteins.

  11. In situ mercury stabilization

    SciTech Connect

    Fuhrmann, M.; Kalb, P.; Adams, J.

    2004-09-01

    BNL Royalty Project Internal Status Report. The funds from the allotment of royalty income were used to experimentally explore feasibility of related, potential new techniques based on the Environmental Sciences Department successful technology licensed for the ex situ treatment of mercury. Specifically, this work is exploring the concept of using Sulfur Polymer Cement (SPC) in an in situ application to stabilize and/or remove mercury (Hg) from surficial soil. Patent disclosure forms have been filed for this process. Soil was artificially spiked with 500 ppm Hg and a series of experiments were set up in which SPC rods were placed in the center of a mass of this soil. Some experiments were conducted at 20 C and others at 50 C. After times ranging from 11 to 24 days, these experiments were opened, photographed and the soil was sampled from discrete locations in the containers. The soil and SPC samples were analyzed for Fe and Hg by x-ray fluorescence. The Hg profile in the soil was significantly altered, with concentrations along the outer edge of the soil reduced by as much as 80% from the starting concentration. Conversely, closer to the treatment rod containing SPC, concentrations of Hg were significantly increased over the original concentration. Preliminary results for elevated temperature sample are shown graphically in Figure 2. Apparently the Hg had migrated toward the SPC and reacted with sulfur to form Hg S. This appears to be a reaction between gaseous phases of both S and Hg, with Hg having a greater vapor pressure. The concentration of low solubility HgS (i.e., low leaching properties) developed within 11 days at 50 C and 21 days at 20 C, confirming the potential of this concept.

  12. IN SITU ENHANCED SOURCE REMOVAL

    EPA Science Inventory

    This html report describes and compares the performance of in situ technologies designed to accelerate the removal of organic contaminants from unconsolidated soils and aquifers. The research was conducted through the Enhanced Source Removal (ESR) Program within the Subsurface Pr...

  13. In Situ Activation of Microcapsules

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)

    2000-01-01

    Disclosed are microcapsules comprising a polymer shell enclosing two or more immiscible liquid phases in which a drug, or a prodrug and a drug activator are partitioned into separate phases. or prevented from diffusing out of the microcapsule by a liquid phase in which the drug is poorly soluble. Also disclosed are methods of using the microcapsules for in situ activation of drugs where upon exposure to an appropriate energy source the internal phases mix and the drug is activated in situ.

  14. In situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  15. Triplex in-situ hybridization

    SciTech Connect

    Fresco, Jacques R.; Johnson, Marion D.

    2002-01-01

    Disclosed are methods for detecting in situ the presence of a target sequence in a substantially double-stranded nucleic acid segment, which comprises: a) contacting in situ under conditions suitable for hybridization a substantially double-stranded nucleic acid segment with a detectable third strand, said third strand being capable of hybridizing to at least a portion of the target sequence to form a triple-stranded structure, if said target sequence is present; and b) detecting whether hybridization between the third strand and the target sequence has occured.

  16. In situ biofilm coupon device

    DOEpatents

    Peyton, B.M.; Truex, M.J.

    1997-06-24

    An apparatus is disclosed for characterization of in-situ microbial biofilm populations in subsurface groundwater. The device permits biofilm-forming microorganisms to adhere to packing material while emplaced in a groundwater strata, so that the packing material can be later analyzed for quantity and type of microorganisms, growth rate, and nutrient requirements. 3 figs.

  17. In situ biofilm coupon device

    DOEpatents

    Peyton, Brent M.; Truex, Michael J.

    1997-01-01

    An apparatus for characterization of in-situ microbial biofilm populations in subsurface groundwater. The device permits biofilm-forming microorganisms to adhere to packing material while emplaced in a groundwater strata, so that the packing material can be later analyzed for quantity and type of microorganisms, growth rate, and nutrient requirements.

  18. In situ vadose zone bioremediation.

    PubMed

    Höhener, Patrick; Ponsin, Violaine

    2014-06-01

    Contamination of the vadose zone with various pollutants is a world-wide problem, and often technical or economic constraints impose remediation without excavation. In situ bioremediation in the vadose zone by bioventing has become a standard remediation technology for light spilled petroleum products. In this review, focus is given on new in situ bioremediation strategies in the vadose zone targeting a variety of other pollutants such as perchlorate, nitrate, uranium, chromium, halogenated solvents, explosives and pesticides. The techniques for biostimulation of either oxidative or reductive degradation pathways are presented, and biotransformations to immobile pollutants are discussed in cases of non-degradable pollutants. Furthermore, research on natural attenuation in the vadose zone is presented.

  19. Integrated in-situ remediation

    SciTech Connect

    Fustos, V.; Lieberman, P.

    1996-01-01

    This article presents an integrated approach to ex-situ and in-situ remediation. A sequence of processes, used successfully in their own right, but used synergistically in this approach, have achieved short-term, economic remediation. In addition the range of contaminants that can be treated is extended. The Process uses ozone, compressed oxygen, water vapor, heat, bioaugmentation and vapor extraction to remediate lower molecular weight hydrocarbons and higher molecular weight hydrocarbons. 3 figs.

  20. In Situ Steam Fracture Experiments.

    DTIC Science & Technology

    1984-12-31

    reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP In Situ Steam Generation Steam Diffusion Downhole 14 1 2 1 J il Properties...in the high- permeability paintbrush-type tuff found in P-Tunnel. All tests were -. performed using downhole steam generation systems capable of...Command, Albuquerque. S-CUBED developed, designed, fabricated, and fielded the downhole , steam - . . generation system. In addition, S-CUBED was

  1. Oldest biliary endoprosthesis in situ

    PubMed Central

    Consolo, Pierluigi; Scalisi, Giuseppe; Crinò, Stefano F; Tortora, Andrea; Giacobbe, Giuseppa; Cintolo, Marcello; Familiari, Luigi; Pallio, Socrate

    2013-01-01

    The advantages of endoscopic retrograde cholangiopancreatography over open surgery have made it the predominant method of treating patients with choledocholithiasis. After sphincterotomy, however, 10%-15% of common bile duct stones cannot be removed with a basket or balloon. The methods for managing “irretrievable stones” include surgery, mechanical lithotripsy, intraductal or extracorporeal shock wave lithotripsy and biliary stenting. The case presented was a referred 82-year-old Caucasian woman with a 7-year-old plastic biliary endoprosthesis in situ. To the best of our knowledge the examined endoprosthesis is the oldest endoprosthesis in situ reported in the literature. Endoscopic biliary endoprosthesis placement remains a simple and safe procedure for patients with stones that are difficult to manage by conventional endoscopic methods and for patients who are unfit for surgery or who are high surgical risks. To date no consensus has been reached regarding how long a biliary prosthesis should remain in situ. Long-term biliary stenting may have a role in selected elderly patients if stones extraction has failed because the procedure may prevent stones impaction and cholangitis. PMID:23858381

  2. Noise canceling in-situ detection

    DOEpatents

    Walsh, David O.

    2014-08-26

    Technologies applicable to noise canceling in-situ NMR detection and imaging are disclosed. An example noise canceling in-situ NMR detection apparatus may comprise one or more of a static magnetic field generator, an alternating magnetic field generator, an in-situ NMR detection device, an auxiliary noise detection device, and a computer.

  3. Composite with In Situ Plenums

    NASA Technical Reports Server (NTRS)

    Montesano, Mark

    2012-01-01

    A document describes a high-performance thermal distribution panel (TDP) concept using high-conductivity (greater than 800 W/mK) macro composite skin with in situ heat pipes. The processing technologies proposed to build such a panel result in a one-piece, inseparable assembly with high conductance in both the X and Y planes. The TDP configuration can also be used to produce panels with high structural stiffness. The one-piece construction of the TDP eliminates the thermal interface between the cooling plenums and the heat spreader base, and obviates the need for bulky mounting flanges and thick heat spreaders used on baseline designs. The conductivity of the TDP can be configured to exceed 800 W/mK with a mass density below 2.5 grams per cubic centimeter. This material can provide efficient conductive heat transfer between the in situ heat plenums, permitting the use of thinner panel thicknesses. The plenums may be used as heat pipes, loop heat pipes, or liquid cooling channels. The panel technology used in the TDP is a macro-composite comprised of aluminum-encapsulated annealed pyrolytic graphite (APG). APG is highly aligned crystalline graphite with an in-plane thermal conductivity of 1,700 W/mK. APG has low shear strength and does not constrain the encapsulating material. The proposed concept has no thermal interfaces between the heat pipes and the spreader plate, further improving the overall conductance of the system. The in situ plenums can also be used for liquid cooling applications. The process can be used to fabricate structural panels by adding a second thin sheet.

  4. Developments in in situ hybridisation.

    PubMed

    Cassidy, Andrew; Jones, Julia

    2014-11-01

    In situ hybridisation (ISH) is an established family of closely related methods for the detection and visualisation of specific nucleic acid sequences (DNA, RNA) in tissue sections, cytological preparations and whole organisms. The technique has a history of refinements and applications going back over several decades and is routinely employed in laboratories where visualisation of gene expression directly within the tissue of interest is necessary. This article will focus on ISH methods for the demonstration of messenger RNA (mRNA) and micro RNA (miRNA) in formalin-fixed paraffin-embedded (FFPE) tissues with emphasis on non-radioactive signal detection strategies currently available.

  5. In Situ Mosaic Brightness Correction

    NASA Technical Reports Server (NTRS)

    Deen, Robert G.; Lorre, Jean J.

    2012-01-01

    In situ missions typically have pointable, mast-mounted cameras, which are capable of taking panoramic mosaics comprised of many individual frames. These frames are mosaicked together. While the mosaic software applies radiometric correction to the images, in many cases brightness/contrast seams still exist between frames. This is largely due to errors in the radiometric correction, and the absence of correction for photometric effects in the mosaic processing chain. The software analyzes the overlaps between adjacent frames in the mosaic and determines correction factors for each image in an attempt to reduce or eliminate these brightness seams.

  6. In-situ spectrophotometric probe

    DOEpatents

    Prather, William S.

    1992-01-01

    A spectrophotometric probe for in situ absorption spectra measurements comprising a first optical fiber carrying light from a remote light source, a second optical fiber carrying light to a remote spectrophotometer, the proximal ends of the first and second optical fibers parallel and coterminal, a planoconvex lens to collimate light from the first optical fiber, a reflecting grid positioned a short distance from the lens to reflect the collimated light back to the lens for focussing on the second optical fiber. The lens is positioned with the convex side toward the optical fibers. A substrate for absorbing analyte or an analyte and reagent mixture may be positioned between the lens and the reflecting grid.

  7. In-situ spectrophotometric probe

    DOEpatents

    Prather, W.S.

    1992-12-15

    A spectrophotometric probe is described for in situ absorption spectra measurements comprising a first optical fiber carrying light from a remote light source, a second optical fiber carrying light to a remote spectrophotometer, the proximal ends of the first and second optical fibers parallel and co-terminal, a planoconvex lens to collimate light from the first optical fiber, a reflecting grid positioned a short distance from the lens to reflect the collimated light back to the lens for focusing on the second optical fiber. The lens is positioned with the convex side toward the optical fibers. A substrate for absorbing analyte or an analyte and reagent mixture may be positioned between the lens and the reflecting grid. 5 figs.

  8. In situ Mars ozone detector

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee; Weinstock, Elliot M.

    1994-01-01

    We propose sending a balloon-borne UV photometer sensor package to measure atmospheric ozone on Mars, and this package could be a Discovery Program sensor candidate. Past measurements of ozone on Mars are highly uncertain, perhaps a factor of 3 or so uncertain, due primarily to interference and masking by cloud and dust. In-situ balloon measurements would avoid these problems, and would provide 'ground truth' which remote sensing techniques cannot. We have explored this approach to measure ozone abundance in the terrestrial stratosphere with a balloon-borne UV absorption photometer. Atmospheric pressures and temperatures and ozone concentrations near the surface of Mars are similar to those in the terrestrial stratosphere.

  9. In-situ measurement system

    DOEpatents

    Lord, David E.

    1983-01-01

    A multipurpose in situ underground measurement system comprising a plurality of long electrical resistance elements in the form of rigid reinforcing bars, each having an open loop "hairpin" configuration of shorter length than the other resistance elements. The resistance elements are arranged in pairs in a unitized structure, and grouted in place in the underground volume. The electrical resistance of each element and the difference in electrical resistance of the paired elements are obtained, which difference values may be used in analytical methods involving resistance as a function of temperature. A scanner sequentially connects the resistance-measuring apparatus to each individual pair of elements. A source of heating current is also selectively connectable for heating the elements to an initial predetermined temperature prior to electrical resistance measurements when used as an anemometer.

  10. Training for teamwork through in situ simulations.

    PubMed

    Sorensen, Asta; Poehlman, Jon; Bollenbacher, John; Riggan, Scott; Davis, Stan; Miller, Kristi; Ivester, Thomas; Kahwati, Leila

    2015-07-01

    In situ simulations allow healthcare teams to practice teamwork and communication as well as clinical management skills in a team's usual work setting with typically available resources and equipment. The purpose of this video is to demonstrate how to plan and conduct in situ simulation training sessions, with particular emphasis on how such training can be used to improve communication and teamwork. The video features an in situ simulation conducted at a labour and delivery unit in response to postpartum hemorrhage.

  11. Amplification of chromosomal DNA in situ

    DOEpatents

    Christian, Allen T.; Coleman, Matthew A.; Tucker, James D.

    2002-01-01

    Amplification of chromosomal DNA in situ to increase the amount of DNA associated with a chromosome or chromosome region is described. The amplification of chromosomal DNA in situ provides for the synthesis of Fluorescence in situ Hybridization (FISH) painting probes from single dissected chromosome fragments, the production of cDNA libraries from low copy mRNAs and improved in Comparative Genomic Hybridization (CGH) procedures.

  12. Training for teamwork through in situ simulations

    PubMed Central

    Sorensen, Asta; Poehlman, Jon; Bollenbacher, John; Riggan, Scott; Davis, Stan; Miller, Kristi; Ivester, Thomas; Kahwati, Leila

    2015-01-01

    In situ simulations allow healthcare teams to practice teamwork and communication as well as clinical management skills in a team's usual work setting with typically available resources and equipment. The purpose of this video is to demonstrate how to plan and conduct in situ simulation training sessions, with particular emphasis on how such training can be used to improve communication and teamwork. The video features an in situ simulation conducted at a labour and delivery unit in response to postpartum hemorrhage. PMID:26294962

  13. ENGINEERING BULLETIN: IN SITU STEAM EXTRACTION TREATMENT

    EPA Science Inventory

    In situ steam extraction removes volatile and semivolatile hazardous contaminants from soil and groundwater without excavation of the hazardous waste. Waste constituents are removed in situ by the technology and are not actually treated. The use of steam enhances the stripping of...

  14. ENGINEERING BULLETIN: IN SITU STEAM EXTRACTION TREATMENT

    EPA Science Inventory

    In situ steam extraction removes volatile and semivolatile hazardous contaminants from soil and groundwater without excavation of the hazardous waste. Waste constituents are removed in situ by the technology and are not actually treated. The use of steam enhances the stripping of...

  15. In situ vitrification: A review

    SciTech Connect

    Cole, L.L.; Fields, D.E.

    1989-11-01

    The in situ vitrification process (ISV) converts contaminated soils and sludges to a glass and crystalline product. The process appears to be ideally suited for on site treatment of both wet and dry wastes. Basically, the system requires four molybdenum electrodes, an electrical power system for vitrifying the soil, a hood to trap gaseous effluents, an off-gas treatment system, an off-gas cooling system, and a process control station. Mounted in three transportable trailers, the ISV process can be moved from site to site. The process has the potential for treating contaminated soils at most 13 m deep. The ISV project has won a number of outstanding achievement awards. The process has also been patented with exclusive worldwide rights being granted to Battelle Memorial Institute for nonradioactive applications. While federal applications still belong to the Department of Energy, Battelle transferred the rights of ISV for non-federal government, chemical hazardous wastes to a separate corporation in 1989 called Geosafe. This report gives a review of the process including current operational behavior and applications.

  16. In situ bioremediation in Europe

    SciTech Connect

    Porta, A.; Young, J.K.; Molton, P.M.

    1993-06-01

    Site remediation activity in Europe is increasing, even if not at the forced pace of the US. Although there is a better understanding of the benefits of bioremediation than of other approaches, especially about in situ bioremediation of contaminated soils, relatively few projects have been carried out full-scale in Europe or in the US. Some engineering companies and large industrial companies in Europe are investigating bioremediation and biotreatment technologies, in some cases to solve their internal waste problems. Technologies related to the application of microorganisms to the soil, release of nutrients into the soil, and enhancement of microbial decontamination are being tested through various additives such as surfactants, ion exchange resins, limestone, or dolomite. New equipment has been developed for crushing and mixing or injecting and sparging the microorganisms, as have new reactor technologies (e.g., rotating aerator reactors, biometal sludge reactors, and special mobile containers for simultaneous storage, transportation, and biodegradation of contaminated soil). Some work has also been done with immobilized enzymes to support and restore enzymatic activities related to partial or total xenobiotic decontamination. Finally, some major programs funded by public and private institutions confirm that increasing numbers of firms have a working interest in bioremediation.

  17. Method for in situ combustion

    DOEpatents

    Pasini, III, Joseph; Shuck, Lowell Z.; Overbey, Jr., William K.

    1977-01-01

    This invention relates to an improved in situ combustion method for the recovery of hydrocarbons from subterranean earth formations containing carbonaceous material. The method is practiced by penetrating the subterranean earth formation with a borehole projecting into the coal bed along a horizontal plane and extending along a plane disposed perpendicular to the plane of maximum permeability. The subterranean earth formation is also penetrated with a plurality of spaced-apart vertical boreholes disposed along a plane spaced from and generally parallel to that of the horizontal borehole. Fractures are then induced at each of the vertical boreholes which project from the vertical boreholes along the plane of maximum permeability and intersect the horizontal borehole. The combustion is initiated at the horizontal borehole and the products of combustion and fluids displaced from the earth formation by the combustion are removed from the subterranean earth formation via the vertical boreholes. Each of the vertical boreholes are, in turn, provided with suitable flow controls for regulating the flow of fluid from the combustion zone and the earth formation so as to control the configuration and rate of propagation of the combustion zone. The fractures provide a positive communication with the combustion zone so as to facilitate the removal of the products resulting from the combustion of the carbonaceous material.

  18. Chemically enhanced in situ recovery

    SciTech Connect

    Sale, T.; Pitts, M.; Wyatt, K.

    1996-08-01

    Chemically enhanced recovery is a promising alternative to current technologies for management of subsurface releases of organic liquids. Through the inclusion of surfactants, solvents, polymers, and/or alkaline agents to a waterflood, the transport of targeted organic compounds can be increased and rates of recovery enhanced. By far, the vast majority of work done in the field of chemically enhanced recovery has been at a laboratory scale. The following text focuses on chemically enhanced recovery from a field application perspective with emphasis given to chlorinated solvents in a low permeability setting. While chlorinated solvents are emphasized, issues discussed are also relevant to organic liquids less dense than water such as petroleum products. Topics reviewed include: (1) Description of technology; (2) General technology considerations; (3) Low permeability media considerations; (4) Cost and reliability considerations; (5) Commercial availability; and (6) Case histories. Through this paper an appreciation is developed of both the potential and limitations of chemically enhanced recovery. Excluded from the scope of this paper is the in situ destruction of organic compounds through processes such as chemical or biological oxidation, chemically enhanced recovery of inorganic compounds, and ex situ soil treatment processes. 11 refs., 2 figs., 1 tab.

  19. Frontiers of in situ electron microscopy

    DOE PAGES

    Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying

    2015-01-01

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by inmore » this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.« less

  20. Perspectives on in situ electron microscopy

    DOE PAGES

    Zheng, Haimei; Zhu, Yimei

    2017-03-29

    In situ transmission electron microscopy (TEM) with the ability to reveal materials dynamic processes with high spatial and temporal resolution has attracted significant interest. The recent advances in in situ methods, including liquid and gas sample environment, pump-probe ultrafast microscopy, nanomechanics and ferroelectric domain switching the aberration corrected electron optics as well as fast electron detector has opened new opportunities to extend the impact of in situ TEM in broad areas of research ranging from materials science to chemistry, physics and biology. Here in this paper, we highlight the development of liquid environment electron microscopy and its applications in themore » study of colloidal nanoparticle growth, electrochemical processes and others; in situ study of topological vortices in ferroelectric and ferromagnetic materials. At the end, perspectives of future in situ TEM are provided.« less

  1. In situ bioremediation using horizontal wells

    SciTech Connect

    1995-04-01

    In Situ Bioremediation (ISB), which is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation, remediates soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISB involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove .VOCs from the vadose zone concomitant with biodegradation of VOCs. The innovation is in the combination of 3 emerging technologies, air stripping, horizontal wells, and bioremediation via gaseous nutrient injection with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

  2. Improving in Situ Cosmogenic Chronometers

    NASA Astrophysics Data System (ADS)

    Clark, Douglas H.; Bierman, Paul R.; Larsen, Patrick

    1995-11-01

    New radiocarbon ages for Sierra Nevada deglaciation, the first 10 Be measurements from the Laurentide terminal moraine, and calculations based on paleomagnetic field strength have the potential to substantially improve the accuracy of cosmogenic age estimates. Specifically, three new constraints apply to the interpretation of measured abundances of in situ produced cosmogenic 10Be and 26Al: (1) A suite of minimum-limiting radiocarbon dates indicates that the Sierra Nevada was deglaciated at least several thousand years earlier than assumed when Nishiizumi et al. (1989) first calibrated 10Be and 26 Al production rates based on polished bedrock surfaces in the range, with retreat beginning by 18,000 cal yr B.P. and completed by 13,000 cal yr B.P. (2) Concentrations of 10Be in moraine boulders and glacier-polished bedrock in New Jersey show little variance (10%, 1σ) and can be used to calculate a preliminary 10Be production rate (integrated over the past 21,000-22,000 cal yr B.P. at 41°, 200-300 m altitude) that is about 20% lower than currently accepted. (3) Calculations of the effect of past geomagnetic field-strength variations on production rates suggest that the use of temporally averaged production rates may generate age errors of >20%; however, cosmogenic exposure ages can be corrected for this effect, although the corrections currently are imprecise. Many previously reported late-Pleistocene 10Be and 26Al exposure ages are probably too young and are less accurate and less precise than implied by reported uncertainties. The discrepancy between accepted production rates and those calculated from Laurentide exposures, when considered together with the Sierran deglacial chronology and the model results, suggest that correlations between cosmogenic and other numerical ages, especially for brief events like the Younger Dryas and Heinrich events, will not be robust until temporal variations and the altitude/latitude scaling of production rates are fully understood

  3. ENHANCED BIODEGRADATION THROUGH IN-SITU AERATION

    EPA Science Inventory

    This presentation provided an overview of enhanced aerobic bioremediation using in-situ aeration or venting. The following topics were covered: (1) Basic discussion on biodegradation and respiration testing; (2) Basic discussion on volatilization, rate-limited mass transport, an...

  4. Direct in situ rt-PCR.

    PubMed

    Lossi, Laura; Gambino, Graziana; Salio, Chiara; Merighi, Adalberto

    2011-01-01

    In situ polymerase chain reaction (PCR) is a histological technique that exploits the advantages of PCR for detection of mRNA directly in tissue sections. It somehow conjugates together PCR and in situ hybridization that is more traditionally employed for mRNA localization in cell organelles, intact cells, or tissue sections. This chapter describes the application of in situ PCR for neuropeptide mRNA localization. We provide here a detailed protocol for direct in situ reverse transcription (RT) PCR (RT-PCR) with nonradioactive probes after fixation and paraffin embedding or cryosectioning. Digoxigenin-labeled nucleotides (digoxigenin-11-dUTP) are incorporated in the PCR product after RT and subsequently detected with an anti-digoxigenin antibody conjugated with alkaline phosphatase. The procedure can be modified for use with fluorescent probes and employed in combination with enzyme/fluorescence immunocytochemical labeling.

  5. DOE In Situ Remediation Integrated Program. In situ manipulation technologies subprogram plan

    SciTech Connect

    Yow, J.L. Jr.

    1993-12-22

    The In Situ Remediation Integrated Program (ISRP) supports and manages a balanced portfolio of applied research and development activities in support of DOE environmental restoration and waste management needs. ISRP technologies are being developed in four areas: containment, chemical and physical treatment, in situ bioremediation, and in situ manipulation (including electrokinetics). the focus of containment is to provide mechanisms to stop contaminant migration through the subsurface. In situ bioremediation and chemical and physical treatment both aim to destroy or eliminate contaminants in groundwater and soils. In situ manipulation (ISM) provides mechanisms to access contaminants or introduce treatment agents into the soil, and includes other technologies necessary to support the implementation of ISR methods. Descriptions of each major program area are provided to set the technical context of the ISM subprogram. Typical ISM needs for major areas of in situ remediation research and development are identified.

  6. In Situ Forming Polymeric Drug Delivery Systems

    PubMed Central

    Madan, M.; Bajaj, A.; Lewis, S.; Udupa, N.; Baig, J. A.

    2009-01-01

    In situ forming polymeric formulations are drug delivery systems that are in sol form before administration in the body, but once administered, undergo gelation in situ, to form a gel. The formation of gels depends on factors like temperature modulation, pH change, presence of ions and ultra violet irradiation, from which the drug gets released in a sustained and controlled manner. Various polymers that are used for the formulation of in situ gels include gellan gum, alginic acid, xyloglucan, pectin, chitosan, poly(DL-lactic acid), poly(DL-lactide-co-glycolide) and poly-caprolactone. The choice of solvents like water, dimethylsulphoxide, N-methyl pyrrolidone, triacetin and 2-pyrrolidone for these formulations depends on the solubility of polymer used. Mainly in situ gels are administered by oral, ocular, rectal, vaginal, injectable and intraperitoneal routes. The in situ gel forming polymeric formulations offer several advantages like sustained and prolonged action in comparison to conventional drug delivery systems. The article presents a detailed review of these types of polymeric systems, their evaluation, advancements and their commercial formulations. From a manufacturing point of view, the production of such devices is less complex and thus lowers the investment and manufacturing cost. PMID:20490289

  7. In-situ retorting of oil shale

    SciTech Connect

    Peters, G.G.; West, R.C.

    1984-11-20

    Fluid, such as liquid water, is injected into the rock surrounding an in situ oil shale retort at sufficient pressure and flow rate so that the injected fluid flows toward the retort to block the path of hot liquid and gaseous kerogen decomposition products escaping from the retort and to return heat to the retort. The successful conduct of an oil shale retorting operation usually requires that the retort temperature be maintained at a temperature sufficient to decompose efficiently the kerogen contained in the oil shale. By reducing the heat loss from an active retort, the amount of energy required to maintain a desired temperature therein is reduced. The fluid injection method also maintains pressure in an in-situ oil shale retort, allowing in-situ oil shale retorting to be efficiently conducted at a desired pressure. The method also reduces the danger to mineworkers who may be engaged in adjacent mining operations due to the escape of hazardous gases from an active retort. The method allows a series of sequential in-situ oil shale retorts in an oil shale formation to be placed more closely together than previously practical by reducing hot fluid leakage from each active retort to one or more abandoned retorts adjacent thereto, thus improving the recovery factor from the formation. The method also minimizes contamination of the formation surrounding an active in-situ retort due to hazardous chemicals which may be contained in the kerogen decomposition products leaking from the retort.

  8. The SMAP In Situ Soil Moisture Sensor Testbed: Comparing in situ sensors for satellite validation

    USDA-ARS?s Scientific Manuscript database

    One of the most valuable tools in validating satellite based soil moisture estimates, such as those from the Soil Moisture Active Passive (SMAP) mission are large scale in situ networks. Global validation involves networks operated by many different organizations. Existing in situ soil moisture netw...

  9. In situ macromolecular crystallography using microbeams

    PubMed Central

    Axford, Danny; Owen, Robin L.; Aishima, Jun; Foadi, James; Morgan, Ann W.; Robinson, James I.; Nettleship, Joanne E.; Owens, Raymond J.; Moraes, Isabel; Fry, Elizabeth E.; Grimes, Jonathan M.; Harlos, Karl; Kotecha, Abhay; Ren, Jingshan; Sutton, Geoff; Walter, Thomas S.; Stuart, David I.; Evans, Gwyndaf

    2012-01-01

    Despite significant progress in high-throughput methods in macromolecular crystallography, the production of diffraction-quality crystals remains a major bottleneck. By recording diffraction in situ from crystals in their crystallization plates at room temperature, a number of problems associated with crystal handling and cryoprotection can be side-stepped. Using a dedicated goniometer installed on the microfocus macromolecular crystallography beamline I24 at Diamond Light Source, crystals have been studied in situ with an intense and flexible microfocus beam, allowing weakly diffracting samples to be assessed without a manual crystal-handling step but with good signal to noise, despite the background scatter from the plate. A number of case studies are reported: the structure solution of bovine enterovirus 2, crystallization screening of membrane proteins and complexes, and structure solution from crystallization hits produced via a high-throughput pipeline. These demonstrate the potential for in situ data collection and structure solution with microbeams. PMID:22525757

  10. In Situ Vitrification Treatability Study Work Plan

    SciTech Connect

    Charboneau, B.L.; Landon, J.L.

    1989-03-01

    The Buried Waste Program was established in October, 1987 to accelerate the studies needed to develop a recommended long-term management plan for the buried mixed waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. The In Situ Vitrification Project is being conducted in a Comprehensive Environmental Response, Compensation, and Liability Act Feasibility Study format to identify methods for the long-term management of the mixed waste buried. This In Situ Vitrification Treatability Study Work Plan gives a brief description of the site, work breakdown structure, and project organization: the in situ vitrification technology; the purpose of the tests and demonstrations; and the equipment and materials required for the tests and demonstration. 5 refs., 6 figs., 3 tabs.

  11. In situ remediation of the geoenvironment

    SciTech Connect

    Evans, J.C.

    1997-12-31

    This document contains the Proceedings of the Conference on In-Situ Remediation of the Geoenvironment held in Minneapolis, Minnesota, October 5-8, 1997. The progress in the development and implementation of techniques for the remediation of contaminated soils and ground water has been and continues to be rapid. These proceedings focus on the in-situ remediation of the geoenvironment and are a result of contributions by academicians, practicing engineers, and contractors. Contributors include the Environmental Engineering Division and the Geo-Institute. Contaminants discussed include petroleum hydrocarbons, cadmium, hexavalent chromium, BTEX, TCE, NAPL`s and various other hazardous wastes. Technologies discussed include permeable reactive barriers, soil vapor extraction, air sparging, containment, barrier walls, slurry walls, vibro-sealing, NAPL`s, stabilization, electrokinetics, vertical drains, radio frequency heating, in-situ oxidation, and others.

  12. In situ macromolecular crystallography using microbeams.

    PubMed

    Axford, Danny; Owen, Robin L; Aishima, Jun; Foadi, James; Morgan, Ann W; Robinson, James I; Nettleship, Joanne E; Owens, Raymond J; Moraes, Isabel; Fry, Elizabeth E; Grimes, Jonathan M; Harlos, Karl; Kotecha, Abhay; Ren, Jingshan; Sutton, Geoff; Walter, Thomas S; Stuart, David I; Evans, Gwyndaf

    2012-05-01

    Despite significant progress in high-throughput methods in macromolecular crystallography, the production of diffraction-quality crystals remains a major bottleneck. By recording diffraction in situ from crystals in their crystallization plates at room temperature, a number of problems associated with crystal handling and cryoprotection can be side-stepped. Using a dedicated goniometer installed on the microfocus macromolecular crystallography beamline I24 at Diamond Light Source, crystals have been studied in situ with an intense and flexible microfocus beam, allowing weakly diffracting samples to be assessed without a manual crystal-handling step but with good signal to noise, despite the background scatter from the plate. A number of case studies are reported: the structure solution of bovine enterovirus 2, crystallization screening of membrane proteins and complexes, and structure solution from crystallization hits produced via a high-throughput pipeline. These demonstrate the potential for in situ data collection and structure solution with microbeams.

  13. Scientific rationale for Saturn's in situ exploration

    NASA Astrophysics Data System (ADS)

    Mousis, O.; Fletcher, L. N.; Lebreton, J.-P.; Wurz, P.; Cavalié, T.; Coustenis, A.; Courtin, R.; Gautier, D.; Helled, R.; Irwin, P. G. J.; Morse, A. D.; Nettelmann, N.; Marty, B.; Rousselot, P.; Venot, O.; Atkinson, D. H.; Waite, J. H.; Reh, K. R.; Simon, A. A.; Atreya, S.; André, N.; Blanc, M.; Daglis, I. A.; Fischer, G.; Geppert, W. D.; Guillot, T.; Hedman, M. M.; Hueso, R.; Lellouch, E.; Lunine, J. I.; Murray, C. D.; O`Donoghue, J.; Rengel, M.; Sánchez-Lavega, A.; Schmider, F.-X.; Spiga, A.; Spilker, T.; Petit, J.-M.; Tiscareno, M. S.; Ali-Dib, M.; Altwegg, K.; Bolton, S. J.; Bouquet, A.; Briois, C.; Fouchet, T.; Guerlet, S.; Kostiuk, T.; Lebleu, D.; Moreno, R.; Orton, G. S.; Poncy, J.

    2014-12-01

    Remote sensing observations meet some limitations when used to study the bulk atmospheric composition of the giant planets of our solar system. A remarkable example of the superiority of in situ probe measurements is illustrated by the exploration of Jupiter, where key measurements such as the determination of the noble gases' abundances and the precise measurement of the helium mixing ratio have only been made available through in situ measurements by the Galileo probe. This paper describes the main scientific goals to be addressed by the future in situ exploration of Saturn placing the Galileo probe exploration of Jupiter in a broader context and before the future probe exploration of the more remote ice giants. In situ exploration of Saturn's atmosphere addresses two broad themes that are discussed throughout this paper: first, the formation history of our solar system and second, the processes at play in planetary atmospheres. In this context, we detail the reasons why measurements of Saturn's bulk elemental and isotopic composition would place important constraints on the volatile reservoirs in the protosolar nebula. We also show that the in situ measurement of CO (or any other disequilibrium species that is depleted by reaction with water) in Saturn's upper troposphere may help constraining its bulk O/H ratio. We compare predictions of Jupiter and Saturn's bulk compositions from different formation scenarios, and highlight the key measurements required to distinguish competing theories to shed light on giant planet formation as a common process in planetary systems with potential applications to most extrasolar systems. In situ measurements of Saturn's stratospheric and tropospheric dynamics, chemistry and cloud-forming processes will provide access to phenomena unreachable to remote sensing studies. Different mission architectures are envisaged, which would benefit from strong international collaborations, all based on an entry probe that would descend

  14. Flat carcinoma in Situ of bladder.

    PubMed

    Riddle, P R; Chisholm, G D; Trott, P A; Pugh, R C

    1975-01-01

    36 patients with flat carcinoma in situ of the bladder have been reviewed. Those with widespread disease usually presented with dysuria or obstructive outflow tract symptoms and radical surgery appeared to give better results than radiotherapy. However, when the lesion was confined to small areas of the bladder mucosa, haematuria or pain were the main presenting symptoms and a conservative approach seemed justified. It is suggested that the term flat carcinoma in situ be used for this lesion whose behavior differs significantly from that of the commoner papillary or invasive tumours. The pathological appearances are to be reported elsewhere in full.

  15. In-situ vitrification of waste materials

    SciTech Connect

    Powell, James R.; Reich, Morris; Barletta, Robert

    1997-11-14

    A method for the in-situ vitrification of waste materials in a disposable can that includes an inner container and an outer container is disclosed. The method includes the steps of adding frit and waste materials to the inner container, removing any excess water, heating the inner container such that the frit and waste materials melt and vitrify after cooling, while maintaining the outer container at a significantly lower temperature than the inner container. The disposable can is then cooled to ambient temperatures and stored. A device for the in-situ vitrification of waste material in a disposable can is also disclosed.

  16. RNA in situ hybridization in Arabidopsis.

    PubMed

    Wu, Miin-Feng; Wagner, Doris

    2012-01-01

    RNA in situ hybridization using digoxigenin-labeled riboprobes on tissue sections is a powerful technique for revealing microscopic spatial gene expression. Here, we describe an in situ hybridization method commonly practiced in Arabidopsis research labs. The highly stringent hybridization condition eliminates the usage of Ribonlucease A and gives highly specific signals. This also allows the use of longer probes which enhance signal strength without cross hybridization to closely related genes. In addition, using spin columns in template and riboprobe purification greatly reduces background signals.

  17. In-situ vitrification of waste materials

    DOEpatents

    Powell, J.R.; Reich, M.; Barletta, R.

    1997-10-14

    A method for the in-situ vitrification of waste materials in a disposable can that includes an inner container and an outer container is disclosed. The method includes the steps of adding frit and waste materials to the inner container, removing any excess water, heating the inner container such that the frit and waste materials melt and vitrify after cooling, while maintaining the outer container at a significantly lower temperature than the inner container. The disposable can is then cooled to ambient temperatures and stored. A device for the in-situ vitrification of waste material in a disposable can is also disclosed. 7 figs.

  18. DEMONSTRATION BULLETIN: IN SITU VITRIFICATION - GEOSAFE CORPORATION

    EPA Science Inventory

    in Situ Vitrification (ISV) is designed to treat soils, sludges, sediments, and mine tailings contaminated with organic and inorganic compounds. The process uses electrical current to heat (mett) and vitrify the soil in place. Organic contaminants are decomposed by the extreme h...

  19. In Situ Vitrification software requirements specification

    SciTech Connect

    Grush, W.H.; Marwil, E.S.

    1990-09-01

    This report describes the Software Requirements Specification for the Electrical Resistance Heating and Thermal Energy Transport models of the In-Situ Vitrification (ISV) process. It contains the Data Flow Diagrams, Process Specifications, Data Structure Diagrams, and the Data Dictionary. 5 refs.

  20. ENGINEERING BULLETIN: IN SITU VITRIFICATION TREATMENT

    EPA Science Inventory

    In situ vitrification (ISV) uses electrical power to heat and melt soil, sludge, mine tailings, buried wastes, and sediments contaminated with organic, inorganic, and metal-bearing hazardous wastes. The molten material cools to form a hard, monolithic, chemically inert, stable...

  1. DEMONSTRATION BULLETIN: IN SITU VITRIFICATION - GEOSAFE CORPORATION

    EPA Science Inventory

    in Situ Vitrification (ISV) is designed to treat soils, sludges, sediments, and mine tailings contaminated with organic and inorganic compounds. The process uses electrical current to heat (mett) and vitrify the soil in place. Organic contaminants are decomposed by the extreme h...

  2. Mars In Situ Water Extractor (MISWE)

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Paulsen, G.; Craft, J.; Oryshchyn, L.; Sanders, J.; Mueller, R.

    2012-06-01

    We present a method for extracting water in-situ. A deep fluted drill acquires icy-soil, retracts into a cylindrical reactor where heat or microwaves are used to sublime ice, and dumps dry soil on the ground. Water vapor is captured onto cold finger.

  3. Fabrication Capabilities Utilizing In Situ Materials

    NASA Technical Reports Server (NTRS)

    McLemore, Carole A.; Fikes, John C.; Darby, Charles A.; Good, James E.; Gilley, Scott D.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) has a Space Exploration Policy that lays out a plan that far exceeds the earlier Apollo goals where landing on the moon and taking those first historic steps fulfilled the mission. The policy states that we will set roots on the moon by establishing an outpost. This outpost will be used as a test bed for residing in more distant locales, such as Mars. In order to become self-sufficient, the occupants must have the capability to fabricate component parts in situ. Additionally, in situ materials must be used to minimize valuable mission upmass and to be as efficient as possible. In situ materials can be found from various sources such as raw lunar regolith whereby specific constituents can be extracted from the regolith (such as aluminum, titanium, or iron), and existing hardware already residing on the moon from past Apollo missions. The Electron Beam Melting (EBM) process lends itself well to fabricating parts, tools, and other necessary items using in situ materials and will be discussed further in this paper.

  4. Controlled in situ etch-back

    NASA Technical Reports Server (NTRS)

    Mattauch, R. J.; Seabaugh, A. C. (Inventor)

    1981-01-01

    A controlled in situ etch-back technique is disclosed in which an etch melt and a growth melt are first saturated by a source-seed crystal and thereafter etch-back of a substrate takes place by the slightly undersaturated etch melt, followed by LPE growth of a layer by the growth melt, which is slightly supersaturated.

  5. ENGINEERING BULLETIN: IN SITU BIODEGRADATION TREATMENT

    EPA Science Inventory

    In situ biodegradation may be used to treat low-to-intermediate concentrations of organic contaminants in place without disturbing or displacing the contaminated media. Although this technology has been used to degrade a limited number of inorganics, specifically cyanide and nitr...

  6. Parametric melting studies for in situ vitrification

    SciTech Connect

    Fryer, M.O.; Hawkes, G.L.; Murray, P.E.

    1991-11-01

    This report describes a series of simulation studies which examine heat conduction and electric heating during in situ vitrification (ISV). The simulation studies determine the effects of soil parameter changes on the ISV process. Changes in heat capacity, thermal conductivity and electrical conductivity are considered. The results of these studies provide a basis for experimental measurement accuracy requirements.

  7. ENGINEERING BULLETIN: IN SITU BIODEGRADATION TREATMENT

    EPA Science Inventory

    In situ biodegradation may be used to treat low-to-intermediate concentrations of organic contaminants in place without disturbing or displacing the contaminated media. Although this technology has been used to degrade a limited number of inorganics, specifically cyanide and nitr...

  8. Refueling with In-Situ Produced Propellants

    NASA Technical Reports Server (NTRS)

    Chato, David J.

    2014-01-01

    In-situ produced propellants have been identified in many architecture studies as key to implementing feasible chemical propulsion missions to destinations beyond lunar orbit. Some of the more noteworthy ones include: launching from Mars to return to Earth (either direct from the surface, or via an orbital rendezvous); using the Earth-Moon Lagrange point as a place to refuel Mars transfer stages with Lunar surface produced propellants; and using Mars Moon Phobos as a place to produce propellants for descent and ascent stages bound for the Mars surface. However successful implementation of these strategies require an ability to successfully transfer propellants from the in-situ production equipment into the propellant tankage of the rocket stage used to move to the desired location. In many circumstances the most desirable location for this transfer to occur is in the low-gravity environment of space. In support of low earth orbit propellant depot concepts, extensive studies have been conducted on transferring propellants in-space. Most of these propellant transfer techniques will be applicable to low gravity operations in other locations. Even ground-based transfer operations on the Moon, Mars, and especially Phobos could benefit from the propellant conserving techniques used for depot refueling. This paper will review the literature of in-situ propellants and refueling to: assess the performance benefits of the use in-situ propellants for mission concepts; review the parallels with propellant depot efforts; assess the progress of the techniques required; and provide recommendations for future research.

  9. "In Situ" Generation of Compressed Inverted Files.

    ERIC Educational Resources Information Center

    Moffat, Alistair; Bell, Timothy A. H.

    1995-01-01

    Discussion of index construction for large text collections highlights a new indexing algorithm designed to create large compressed inverted indexes "in situ." Topics include a computational model, inversion, index compression, merging, experimental test results, effect on retrieval performance, memory restrictions, and dynamic…

  10. In-Situ Burning of Spilled Oil.

    ERIC Educational Resources Information Center

    Allen, Alan A.

    1991-01-01

    Reviews in-situ burning with particular emphasis on how it can be applied in water-related oil spill situations. Presents and discusses the use of nomograms and development of techniques cited for safe and effective ignition and controlled burning of spilled oil. Includes representative oil spill scenarios and possible responses. (15 references)…

  11. ENGINEERING BULLETIN: IN SITU VITRIFICATION TREATMENT

    EPA Science Inventory

    In situ vitrification (ISV) uses electrical power to heat and melt soil, sludge, mine tailings, buried wastes, and sediments contaminated with organic, inorganic, and metal-bearing hazardous wastes. The molten material cools to form a hard, monolithic, chemically inert, stable...

  12. Consolidation of in-situ retort

    SciTech Connect

    Larson, O.A.; Matthews, C.W.

    1980-11-04

    Shale oil is recovered from an underground oil shale deposit by in-situ retorting of rubblized shale in a retort formed in the deposit. Oil shale in a volume in the range of ten to fifty percent of the volume of the retort is mined from the deposit and delivered to the surface to provide void space for the expansion of the shale that occurs on rubblization to form the in-situ retort. The oil shale delivered to the surface is retorted at the surface. After completion of the in-situ retorting, boreholes are drilled downwardly through the retorted shale and a pipe lowered through the borehole to a level near the bottom of the retort. Spent shale from the surface retorting operation is slurried and pumped into the lower end of the in-situ retort. Pumping is continued to squeeze the slurry into the fissures between blocks of spent shale. The slurry is delivered into successively higher levels of the retort and the pumping and squeezing operation repeated at each level. In a preferred operation, slurry discharged into the retort is allowed to set before discharging slurry into the retort at a higher level to avoid excessive hydrostatic pressures on the retort.

  13. Microwaves for chromogenic in situ hybridization.

    PubMed

    Leong, Anthony S-Y; Haffajee, Zenobia

    2011-01-01

    In situ hybridization can be employed in formalin-fixed, paraffin-embedded tissue sections (FFPT) and allows direct visualization of amplified genes and chromosomes in individual cell nuclei. Fluorescence in situ hybridization (FISH) is the most widely employed method, but the fluorescence preparations suffer from the main disadvantages of fading over time and poor visualization, the latter making it difficult to accurately separate invasive from in situ cancer cells. Chromogenic in situ hybridization (CISH) is a viable alternative to FISH in FFPT as it employs a peroxidase reaction to visualize the chromogen thus allowing the convenience of bright field microscopy and the correlation of the visualized gene amplification with cytomorphology. It is relatively less expensive and allows a permanent record, with several studies attesting to its validity. As with FISH, heat pretreatment and enzyme digestion are two critical components of the protocol. We describe a protocol for CISH in which a microwave-induced target retrieval step is introduced as a replacement for heat pretreatment. The same procedure is performed following enzyme digestion to produce consistent signals in amplified and nonamplified cells that are both larger in size and numbers when compared with those produced by the conventional protocol.

  14. IN SITU LEAD IMMOBILIZATION BY APATITE

    EPA Science Inventory

    Lead contamination is of environmental concern due to its effect on human health. The purpose of this study was to develop a technology to immobilize Pb in situ in contaminated soils and wastes using apatite. Hydroxyapatite [Ca10(PO4)6(O...

  15. IN SITU LEAD IMMOBILIZATION BY APATITE

    EPA Science Inventory

    Lead contamination is of environmental concern due to its effect on human health. The purpose of this study was to develop a technology to immobilize Pb in situ in contaminated soils and wastes using apatite. Hydroxyapatite [Ca10(PO4)6(O...

  16. In-Situ Burning of Spilled Oil.

    ERIC Educational Resources Information Center

    Allen, Alan A.

    1991-01-01

    Reviews in-situ burning with particular emphasis on how it can be applied in water-related oil spill situations. Presents and discusses the use of nomograms and development of techniques cited for safe and effective ignition and controlled burning of spilled oil. Includes representative oil spill scenarios and possible responses. (15 references)…

  17. Transesterification in situ of sunflower seed oil

    SciTech Connect

    Harrington, K.J.; D'Arch-Evans, C.

    1985-06-01

    Transesterification of sunflower seed oil in situ has produced methyl and ethyl esters in yields greater than 40% of the dry seed weight. This figure compares with a typical yield of ca. 30% when the esters were prepared in the conventional manner from preextracted seed oil. 14 references.

  18. ENGINEERING BULLETIN: IN SITU SOIL FLUSHING

    EPA Science Inventory

    In situ soil flushing is the extraction of contaminants from the soil with water or other suitable aqueous solutions. Soil flushing is accomplished by passing the extraction fluid through in-place soils using an injection or infiltration process. Extraction fluids must be recover...

  19. In Situ Fiber-Optic Reflectance Monitor

    NASA Technical Reports Server (NTRS)

    Linton, Roger C.; Gray, Perry A.

    1996-01-01

    In situ fiber-optic reflectance monitor serves as simple means of monitoring changes in reflectance of specimen exposed to simulated outerspace or other environments in vacuum chamber. Eliminates need to remove specimen from vacuum chamber, eliminating optical changes and bleaching such removal causes in coatings.

  20. In Situ Remediation Integrated Program: Technology summary

    SciTech Connect

    Not Available

    1994-02-01

    The In Situ Remediation Integrated Program (ISR IP) was instituted out of recognition that in situ remediation could fulfill three important criteria: significant cost reduction of cleanup by eliminating or minimizing excavation, transportation, and disposal of wastes; reduced health impacts on workers and the public by minimizing exposure to wastes during excavation and processing; and remediation of inaccessible sites, including: deep subsurfaces, in, under, and around buildings. Buried waste, contaminated soils and groundwater, and containerized wastes are all candidates for in situ remediation. Contaminants include radioactive wastes, volatile and non-volatile organics, heavy metals, nitrates, and explosive materials. The ISR IP intends to facilitate development of in situ remediation technologies for hazardous, radioactive, and mixed wastes in soils, groundwater, and storage tanks. Near-term focus is on containment of the wastes, with treatment receiving greater effort in future years. ISR IP is an applied research and development program broadly addressing known DOE environmental restoration needs. Analysis of a sample of 334 representative sites by the Office of Environmental Restoration has shown how many sites are amenable to in situ remediation: containment--243 sites; manipulation--244 sites; bioremediation--154 sites; and physical/chemical methods--236 sites. This needs assessment is focused on near-term restoration problems (FY93--FY99). Many other remediations will be required in the next century. The major focus of the ISR EP is on the long term development of permanent solutions to these problems. Current needs for interim actions to protect human health and the environment are also being addressed.

  1. New in situ crosslinking chemistries for hydrogelation

    NASA Astrophysics Data System (ADS)

    Roberts, Meredith Colleen

    Over the last half century, hydrogels have found immense value as biomaterials in a vast number of biomedical and pharmaceutical applications. One subset of hydrogels receiving increased attention is in situ forming gels. Gelling by either bioresponsive self-assembly or mixing of binary crosslinking systems, these technologies are useful in minimally invasive applications as well as drug delivery systems in which the sol-to-gel transition aids the formulation's performance. Thus far, the field of in situ crosslinking hydrogels has received limited attention in the development of new crosslinking chemistries. Moreover, not only does the chemical nature of the crosslinking moieties allow these systems to perform in situ, but they contribute dramatically to the mechanical properties of the hydrogel networks. For example, reversible crosslinks with finite lifetimes generate dynamic viscoelastic gels with time-dependent properties, whereas irreversible crosslinks form highly elastic networks. The aim of this dissertation is to explore two new covalent chemistries for their ability to crosslink hydrogels in situ under physiological conditions. First, reversible phenylboronate-salicylhydroxamate crosslinking was implemented in a binary, multivalent polymeric system. These gels formed rapidly and generated hydrogel networks with frequency-dependent dynamic rheological properties. Analysis of the composition-structure-property relationships of these hydrogels---specifically considering the effects of pH, degree of polymer functionality, charge of the polymer backbone and polymer concentration on dynamic theological properties---was performed. These gels demonstrate diverse mechanical properties, due to adjustments in the binding equilibrium of the pH-sensitive crosslinks, and thus have the potential to perform in a range of dynamic or bioresponsive applications. Second, irreversible catalyst-free "click" chemistry was employed in the hydrogelation of multivalent azide

  2. Computer model of in situ leaching hydrology

    SciTech Connect

    Not Available

    1981-05-01

    A computer program developed by the US Bureau of Mines simulates the hydrologic activity associated with in situ mining. Its purpose is to determine the site specific flow behavior of leachants and groundwater during development, production, and resotration phases of an in situ leaching operations. Model capabilities include arbitrary well patterns and pumping schedules, partially penetrating well screens, directionally anisotropic permeability and natural groundwater flow, in either leaky or nonleaky, confined aquifers and under steady state or time dependent flow conditions. In addition to extensive laboratory testing, the Twin Cites Research Center has closely monitored the application of this model at three different mine sites, and at each site, the solution breakthrough time and the hydraulic head at observation wells were used to tune the model. The model was then used satisfactorily to assess suitability of various well configurations and pumping schedules, in terms of fluid dispersion within the ore pod and fluid excursions into the surrounding aquifer. (JMT)

  3. In situ simulation: identification of systems issues.

    PubMed

    Guise, Jeanne-Marie; Mladenovic, Jeanette

    2013-06-01

    The Institute of Medicine's report, To Err is Human, concluded that "medical errors are not a result of isolated individual actions but rather faulty systems, processes, and conditions that lead people to make mistakes." In situ simulation offers the unique opportunity to train the teams of people who deliver healthcare while enhancing policies, evaluating new technologies, and improving the systems that support the delivery of safe healthcare. For this reason, the Institute of Medicine, the Joint Commission, and the Agency for Healthcare Research and Quality recommend medical simulation as one of the most important safe practice interventions to reduce errors and risks associated with the process of care. This review builds on other reports in this issue and discusses the application of in situ simulation to identify, address, and test systems improvements. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. In situ soil remediation using electrokinetics

    SciTech Connect

    Buehler, M.F.; Surma, J.E.; Virden, J.W.

    1994-11-01

    Electrokinetics is emerging as a promising technology for in situ soil remediation. This technique is especially attractive for Superfund sites and government operations which contain large volumes of contaminated soil. The approach uses an applied electric field to induce transport of both radioactive and hazardous waste ions in soil. The transport mechanisms include electroosmosis, electromigration, and electrophoresis. The feasibility of using electrokinetics to move radioactive {sup 137}Cs and {sup 60}Co at the Hanford Site in Richland, Washington, is discussed. A closed cell is used to provide in situ measurements of {sup 137}Cs and {sup 60}Co movement in Hanford soil. Preliminary results of ionic movement, along with the corresponding current response, are presented.

  5. In-Situ Planetary Chemical Analysis

    NASA Technical Reports Server (NTRS)

    Kounaves, S. P.; Buehler, M. G.; Grannan, S. M.; Hecht, M. H.; Kuhlman, K. R.

    2000-01-01

    Both, the search for evidence of life on Mars and the assessment of the Martian environment in respect to its compatibility with human explorers, will require the ability to measure and understand the aqueous chemistry of the Martian regolith. Direct in-situ chemical analysis is the only method by which chemical biosignatures can be reliably recognized and the toxicity of the regolith accurately assessed. Qualitative and quantitative determination of the aqueous ionic constituents and their concentrations is critical in developing kinetic and thermodynamic models that can be used to accurately predict the potential of the past or present Martian geochemical environment to have either generated or still sustain life. In-situ chemical characterization could provide evidence as to whether the chemical composition of the regolith or evaporates in suspected ancient water bodies have been biologically influenced.

  6. In situ bioremediation of Hanford groundwater

    SciTech Connect

    Skeen, R.S.; Roberson, K.R.; Workman, D.J. ); Petersen, J.N.; Shouche, M. . Dept. of Chemical Engineering)

    1992-04-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy's (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate, carbon tetrachloride (CCl{sub 4}), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and remediation of existing contaminated groundwaters may be required. In situ bioremediation is one technology currently being developed at Hanford to meet the need for cost effective technologies to clean groundwater contaminated with CCl{sub 4}, nitrate, and other organic and inorganic contaminants. This paper focuses on the latest results of an on going effort to develop effective in situ remediation strategies through the use of predictive simulations.

  7. In situ bioremediation of Hanford groundwater

    SciTech Connect

    Skeen, R.S.; Roberson, K.R.; Workman, D.J.; Petersen, J.N.; Shouche, M.

    1992-04-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy`s (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate, carbon tetrachloride (CCl{sub 4}), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and remediation of existing contaminated groundwaters may be required. In situ bioremediation is one technology currently being developed at Hanford to meet the need for cost effective technologies to clean groundwater contaminated with CCl{sub 4}, nitrate, and other organic and inorganic contaminants. This paper focuses on the latest results of an on going effort to develop effective in situ remediation strategies through the use of predictive simulations.

  8. In situ bioremediation of chlorinated solvents

    SciTech Connect

    Semprini, L.

    1995-06-01

    Chlorinated solvents and their natural transformation products are the most frequently observed groundwater contaminants in the United States. In situ bioremediation using anaerobic or aerobic co-metabolic processes is a promising means of cleaning up contaminated aquifers. Studies show that under natural conditions trichloroethylene can be anaerobically degraded to dichloroethylene, vinyl chloride, and ethylene. Pilot scale field studies of in situ aerobic co-metabolic transformations have shown that indigenous microbes grown on phenol are more effective at degrading trichloroethylene and cis-1,2-dichloroethylene than microbes grown on methane. Modeling studies support field observations and indicate that the removal of trichloroethylene and cis-dichloroethylene results from the biostimulation of an indigenous microbial population. Field tests and modeling studies indicate that, at high TCE concentration, degradation becomes stoichiometrically limited. 17 refs., 4 figs., 1 tab.

  9. Quantitative in situ nanoindentation of aluminum films

    SciTech Connect

    Minor, Andrew M.; Stach, Eric A.; Morris Jr., J.W.

    2001-04-04

    We report the development of a method for quantitative, in situ nanoindentation in an electron microscope and its application to study the onset of deformation during the nanoindentation of aluminum films. The load-displacement curve developed during in situ nanoindentation shows the characteristic ''staircase'' instability at the onset of plastic deformation. The instability corresponds to the first appearance of dislocations in previously defect-free grains, and occurs at a force near that measured in conventional nanoindentation experiments on similarly oriented Al grains. Plastic deformation proceeds through the formation and propagation of prismatic loops punched into the material, and half-loops that emanate from the sample surface. This new experimental technique permits the direct observation of the microstructural mechanisms that operate at the onset of deformation.

  10. Inherently safe in situ uranium recovery

    DOEpatents

    Krumhansl, James L; Brady, Patrick V

    2014-04-29

    An in situ recovery of uranium operation involves circulating reactive fluids through an underground uranium deposit. These fluids contain chemicals that dissolve the uranium ore. Uranium is recovered from the fluids after they are pumped back to the surface. Chemicals used to accomplish this include complexing agents that are organic, readily degradable, and/or have a predictable lifetime in an aquifer. Efficiency is increased through development of organic agents targeted to complexing tetravalent uranium rather than hexavalent uranium. The operation provides for in situ immobilization of some oxy-anion pollutants under oxidizing conditions as well as reducing conditions. The operation also artificially reestablishes reducing conditions on the aquifer after uranium recovery is completed. With the ability to have the impacted aquifer reliably remediated, the uranium recovery operation can be considered inherently safe.

  11. In situ bioremediation of chlorinated solvents.

    PubMed Central

    Semprini, L

    1995-01-01

    Chlorinated solvents and their natural transformation products are the most frequently observed groundwater contaminants in the United States. In situ bioremediation using anaerobic or aerobic co-metabolic processes is a promising means of cleaning up contaminated aquifers. Studies show that under natural conditions trichloroethylene can be anaerobically degraded to dichloroethylene, vinyl chloride, and ethylene. Pilot scale field studies of in situ aerobic co-metabolic transformations have shown that indigenous microbes grown on phenol are more effective at degrading trichloroethylene and cis-1,2-dichloroethylene than microbes grown on methane. Modeling studies support field observations and indicate that the removal of trichloroethylene and cis-dichloroethylene results from the biostimulation of an indigenous microbial population. Field tests and modeling studies indicate that, at high TCE concentration, degradation becomes stoichiometrically limited. PMID:8565895

  12. In-Situ Planetary Chemical Analysis

    NASA Technical Reports Server (NTRS)

    Kounaves, S. P.; Buehler, M. G.; Grannan, S. M.; Hecht, M. H.; Kuhlman, K. R.

    2000-01-01

    Both, the search for evidence of life on Mars and the assessment of the Martian environment in respect to its compatibility with human explorers, will require the ability to measure and understand the aqueous chemistry of the Martian regolith. Direct in-situ chemical analysis is the only method by which chemical biosignatures can be reliably recognized and the toxicity of the regolith accurately assessed. Qualitative and quantitative determination of the aqueous ionic constituents and their concentrations is critical in developing kinetic and thermodynamic models that can be used to accurately predict the potential of the past or present Martian geochemical environment to have either generated or still sustain life. In-situ chemical characterization could provide evidence as to whether the chemical composition of the regolith or evaporates in suspected ancient water bodies have been biologically influenced.

  13. Numerical simulation of in situ bioremediation

    SciTech Connect

    Travis, B.J.

    1998-12-31

    Models that couple subsurface flow and transport with microbial processes are an important tool for assessing the effectiveness of bioremediation in field applications. A numerical algorithm is described that differs from previous in situ bioremediation models in that it includes: both vadose and groundwater zones, unsteady air and water flow, limited nutrients and airborne nutrients, toxicity, cometabolic kinetics, kinetic sorption, subgridscale averaging, pore clogging and protozoan grazing.

  14. In situ health monitoring of piezoelectric sensors

    NASA Technical Reports Server (NTRS)

    Jensen, Scott L. (Inventor); Drouant, George J. (Inventor)

    2013-01-01

    An in situ health monitoring apparatus may include an exciter circuit that applies a pulse to a piezoelectric transducer and a data processing system that determines the piezoelectric transducer's dynamic response to the first pulse. The dynamic response can be used to evaluate the operating range, health, and as-mounted resonance frequency of the transducer, as well as the strength of a coupling between the transducer and a structure and the health of the structure.

  15. In-situ studies of nanocatalysis.

    PubMed

    Zhang, Shiran; Nguyen, Luan; Zhu, Yuan; Zhan, Sihui; Tsung, Chia-Kuang Frank; Tao, Franklin Feng

    2013-08-20

    A heterogeneous catalyst in industry consists of nanoparticles with variable crystallite sizes, shapes, and compositions. Its catalytic performance (activity, selectivity, and durability) derives from surface chemistry of catalyst nanoparticles during catalysis. However, the surface chemistry of the catalyst particles during catalysis, termed in-situ information, is a "black box" because of the challenges in characterizing the catalysts during catalysis. The lack of such in-situ information about catalysts has limited the understanding of catalytic mechanisms and the development of catalysts with high selectivity and activity. The challenges in understanding heterogeneous catalysis include measurement of reaction kinetics, identification of reaction intermediates, bridging pressure gap and materials gap. The pressure gap is the difference in surface structure and chemistry between a catalyst during catalysis and under an ultrahigh vacuum (UHV) condition. The materials gap represents the difference between the structural and compositional complexity of industrial catalysts and the well-defined surface of model catalysts of metals or oxides. Development of in-situ characterization using electron spectroscopy and electron microscopy in recent decades has made possible studies of surface chemistry and structure of nanocatalysts under reaction conditions or during catalysis at near ambient pressure. In this Account, we review the new chemistries and structures of nanocatalysts during reactions revealed with in-situ analytical techniques. We discuss changes observed during catalysis including the evolution of composition, oxidation state, phase, and geometric structure of the catalyst surface, and the sintering of catalysts. These surface chemistries and structures have allowed researchers to build a correlation between surface chemistry and structure of active nanocatalysts and their corresponding catalytic performances. Such a correlation provides critical insights for

  16. In situ determination of salinity by PGNAA.

    PubMed

    Borsaru, M; Smith, C; Merritt, J; Aizawa, T; Rojc, A

    2006-05-01

    Salinity is a very important environmental issue all around the world. In many cases salinity was produced from human activities like farming and mining. Different soluble salts contribute to salinity, however, NaCl is the most common salt producing salinity. This work deals with the application of the prompt gamma neutron activation analysis (PGNAA) technique for in situ determination of salinity. The technique is based on the measurement of chlorine, a component of the common salt, by PGNAA.

  17. In situ models, physico-chemical aspects.

    PubMed

    ten Cate, J M

    1994-07-01

    In situ (intra-oral) caries models are used for two purposes. First, they provide information about oral physiological processes. Such information helps to detail our knowledge of the oral ecosystem and to verify conclusions from in vitro experiments. Second, in situ models are utilized to test preventive agents in the phase between laboratory testing and clinical trials. Most investigations involving enamel inserts have been aimed at testing new dentifrices. The experimental designs of such studies usually do not allow one to draw conclusions on physico-chemical processes, e.g., because of single point measurements. Studies of model parameters (lesion type, lesion severity, and de/remineralization in time) constitute only a minority of the research reports. The most striking observation obtained with in situ models has been the significant differences in de/remineralization observed among individuals and, more importantly, within one individual during different time periods and between different sites in the same mouth (for review, see ten Cate et al., 1992). Regardless of this, some general findings can be inferred: During in situ demineralization, up to 62 vol% microns/day may be removed from enamel. For dentin specimens, this value may be as high as 89 vol% microns/day. For remineralization, during fluoride dentifrice treatment, a median deposition rate of 0.7%/day (for lesions with integrated mineral loss values between 2000 and 4000 vol% microns) is found. The rate of deposition seems to be correlated with the extent of the pre-formed lesion. This suggests that the number of sites (crystallite surface) available for calcium phosphate precipitation is an important parameter.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Femtosecond laser in laser in situ keratomileusis

    PubMed Central

    Salomão, Marcella Q.; Wilson, Steven E.

    2014-01-01

    Flap creation is a critical step in laser in situ keratomileusis (LASIK). Efforts to improve the safety and predictability of the lamellar incision have fostered the development of femtosecond lasers. Several advantages of the femtosecond laser over mechanical microkeratomes have been reported in LASIK surgery. In this article, we review common considerations in management and complications of this step in femtosecond laser–LASIK and concentrate primarily on the IntraLase laser because most published studies relate to this instrument. PMID:20494777

  19. In-Situ Study of Atmospheric Ice

    DTIC Science & Technology

    2004-12-01

    IN-SITU STUDY OF ATMOSPHERIC ICE Victor. F. Petrenko * and Michiya Higa Thayer School of Engineering, Dartmouth College 8000 Cummings Hall, Hanover...conductivity ( Petrenko and Whitworth 1999). Thus, it’s possible to distinguish between water and ice by measuring these electrical properties. This paper...Special Rep.83-17. the bottom of the ice sample and large columnar grains Petrenko , V.F. and Whitworth, R.W. (1999) Physics ofIce, were formed on the

  20. Bilateral neuroblastoma in situ associated with microcephaly.

    PubMed Central

    Park, W. S.; Chi, J. G.

    1993-01-01

    We present an autopsy case of a two-day-old female infant with a very unusual combination of neuroblastoma in situ in both adrenals and microcephaly. This baby was born to a 28-year-old mother after 38 weeks of gestation, and died of respiratory difficulty 2 days later. At autopsy, the baby weighted 1,840gm, and the brain was extraordinarily small with a weight of 125gm. The gyral pattern was simplified and irregular. Microscopically massive migration defects, pachygyria, micropolygyria, leptomeningeal glioneuronal islands, small corticospinal tract and heterotopic Purkinje cells in the cerebellum were found. In addition, there were medullary nodules in both adrenals. They measured 0.7 x 0.4cm and 0.7 x 0.3cm, respectively. These nodules showed the typical histological features of undifferentiated neuroblastoma. The tumor nodules were confined to the medullary portion and did not extend to the cortex or contiguous structures meeting the criteria of neuroblastoma in situ. Based on these unusual and seemingly unrelated sets of findings, it is suggested that the histogenesis of neuroblastoma in situ could be a part of the generalized dysontogenic process. PMID:8397936

  1. In Situ Measurement of Aerosol Extinction

    NASA Technical Reports Server (NTRS)

    Strawa, Anthony W.; Castaneda, R.; Owano, T. G.; Bear, D.; Gore, Warren J. (Technical Monitor)

    2001-01-01

    Aerosols are important contributors to the radiative forcing in the atmosphere. Much of the uncertainty in our knowledge of climate forcing is due to uncertainties in the radiative forcing due to aerosols as illustrated in the IPCC reports of the last ten years. Improved measurement of aerosol optical properties, therefore, is critical to an improved understanding of atmospheric radiative forcing. Additionally, attempts to reconcile in situ and remote measurements of aerosol radiative properties have generally not been successful. This is due in part to the fact that it has been impossible to measure aerosol extinction in situ in the past. In this presentation we introduce a new instrument that employs the techniques used in cavity ringdown spectroscopy to measure the aerosol extinction and scattering coefficients in situ. A prototype instrument has been designed and tested in the lab and the field. It is capable of measuring aerosol extinction coefficient to 2x10(exp -6) per meter. This prototype instrument is described and results are presented.

  2. High accuracy in situ radiometric mapping.

    PubMed

    Tyler, Andrew N

    2004-01-01

    In situ and airborne gamma ray spectrometry have been shown to provide rapid and spatially representative estimates of environmental radioactivity across a range of landscapes. However, one of the principal limitations of this technique has been the influence of changes in the vertical distribution of the source (e.g. 137Cs) on the observed photon fluence resulting in a significant reduction in the accuracy of the in situ activity measurement. A flexible approach for single gamma photon emitting radionuclides is presented, which relies on the quantification of forward scattering (or valley region between the full energy peak and Compton edge) within the gamma ray spectrum to compensate for changes in the 137Cs vertical activity distribution. This novel in situ method lends itself to the mapping of activity concentrations in environments that exhibit systematic changes in the vertical activity distribution. The robustness of this approach has been demonstrated in a salt marsh environment on the Solway coast, SW Scotland, with both a 7.6 cm x 7.6 cm NaI(Tl) detector and a 35% n-type HPGe detector. Application to ploughed field environments has also been demonstrated using HPGe detector, including its application to the estimation of field moist bulk density and soil erosion measurement. Ongoing research work is also outlined.

  3. In situ soil water extraction: a review.

    PubMed

    Weihermüller, L; Siemens, J; Deurer, M; Knoblauch, S; Rupp, H; Göttlein, A; Pütz, T

    2007-01-01

    The knowledge of the composition and fluxes of vadose zone water is essential for a wide range of scientific and practical fields, including water-use management, pesticide registration, fate of xenobiotics, monitoring of disposal from mining and industries, nutrient management of agricultural and forest ecosystems, ecology, and environmental protection. Nowadays, water and solute flow can be monitored using either in situ methods or minimally invasive geophysical measurements. In situ information, however, is necessary to interpret most geophysical data sets and to determine the chemical composition of seepage water. Therefore, we present a comprehensive review of in situ soil water extraction methods to monitor solute concentration, solute transport, and to calculate mass balances in natural soils. We distinguished six different sampling devices: porous cups, porous plates, capillary wicks, pan lysimeters, resin boxes, and lysimeters. For each of the six sampling devices we discuss the basic principles, the advantages and disadvantages, and limits of data acquisition. We also give decision guidance for the selection of the appropriate sampling system. The choice of material is addressed in terms of potential contamination, filtering, and sorption of the target substances. The information provided in this review will support scientists and professionals in optimizing their experimental set-up for meeting their specific goals.

  4. In situ Raman mapping of art objects.

    PubMed

    Lauwers, D; Brondeel, Ph; Moens, L; Vandenabeele, P

    2016-12-13

    Raman spectroscopy has grown to be one of the techniques of interest for the investigation of art objects. The approach has several advantageous properties, and the non-destructive character of the technique allowed it to be used for in situ investigations. However, compared with laboratory approaches, it would be useful to take advantage of the small spectral footprint of the technique, and use Raman spectroscopy to study the spatial distribution of different compounds. In this work, an in situ Raman mapping system is developed to be able to relate chemical information with its spatial distribution. Challenges for the development are discussed, including the need for stable positioning and proper data treatment. To avoid focusing problems, nineteenth century porcelain cards are used to test the system. This work focuses mainly on the post-processing of the large dataset which consists of four steps: (i) importing the data into the software; (ii) visualization of the dataset; (iii) extraction of the variables; and (iv) creation of a Raman image. It is shown that despite the challenging task of the development of the full in situ Raman mapping system, the first steps are very promising.This article is part of the themed issue 'Raman spectroscopy in art and archaeology'. © 2016 The Author(s).

  5. Autonomous in situ measurements of seawater alkalinity.

    PubMed

    Spaulding, Reggie S; DeGrandpre, Michael D; Beck, James C; Hart, Robert D; Peterson, Brittany; De Carlo, Eric H; Drupp, Patrick S; Hammar, Terry R

    2014-08-19

    Total alkalinity (AT) is an important parameter for describing the marine inorganic carbon system and understanding the effects of atmospheric CO2 on the oceans. Measurements of AT are limited, however, because of the laborious process of collecting and analyzing samples. In this work we evaluate the performance of an autonomous instrument for high temporal resolution measurements of seawater AT. The Submersible Autonomous Moored Instrument for alkalinity (SAMI-alk) uses a novel tracer monitored titration method where a colorimetric pH indicator quantifies both pH and relative volumes of sample and titrant, circumventing the need for gravimetric or volumetric measurements. The SAMI-alk performance was validated in the laboratory and in situ during two field studies. Overall in situ accuracy was -2.2 ± 13.1 μmol kg(-1) (n = 86), on the basis of comparison to discrete samples. Precision on duplicate analyses of a carbonate standard was ±4.7 μmol kg(-1) (n = 22). This prototype instrument can measure in situ AT hourly for one month, limited by consumption of reagent and standard solutions.

  6. In situ Raman mapping of art objects

    NASA Astrophysics Data System (ADS)

    Lauwers, D.; Brondeel, Ph.; Moens, L.; Vandenabeele, P.

    2016-12-01

    Raman spectroscopy has grown to be one of the techniques of interest for the investigation of art objects. The approach has several advantageous properties, and the non-destructive character of the technique allowed it to be used for in situ investigations. However, compared with laboratory approaches, it would be useful to take advantage of the small spectral footprint of the technique, and use Raman spectroscopy to study the spatial distribution of different compounds. In this work, an in situ Raman mapping system is developed to be able to relate chemical information with its spatial distribution. Challenges for the development are discussed, including the need for stable positioning and proper data treatment. To avoid focusing problems, nineteenth century porcelain cards are used to test the system. This work focuses mainly on the post-processing of the large dataset which consists of four steps: (i) importing the data into the software; (ii) visualization of the dataset; (iii) extraction of the variables; and (iv) creation of a Raman image. It is shown that despite the challenging task of the development of the full in situ Raman mapping system, the first steps are very promising. This article is part of the themed issue "Raman spectroscopy in art and archaeology".

  7. Practical application of in situ aerosol measurement

    SciTech Connect

    O`Hern, T.J.; Rader, D.J.

    1993-09-01

    The use of in situ, real-time measurement techniques permits the characterization of airborne droplets and particles under conditions where traditional sampling methods can fail. For example, sampling method rely on the ability to sample and transport particles without biasing the properties of interest, and often are not applicable in harsh environment. Although in situ methods offer unique opportunities in these cases, these techniques introduce new concerns and must be used carefully if accurate measurement are to be made. Several in situ measurement techniques are reviewed here. As the field is rapidly evolving, the discussion is limited to those techniques which: (1) are commercially available, (2) provide real-time output, (3) measure the aerosol size distribution. Discussion is divided between single particle counters (which provide a flux-based or temporal measurement) and ensemble techniques (which provide a concentration-based or spatial measurement). Specific techniques discussed include phase Doppler, Mie scattering, and Fraunhofer diffraction, and commercial instruments based on these techniques.

  8. In situ rheology of yeast biofilms.

    PubMed

    Brugnoni, Lorena I; Tarifa, María C; Lozano, Jorge E; Genovese, Diego

    2014-01-01

    The aim of the present work was to investigate the in situ rheological behavior of yeast biofilms growing on stainless steel under static and turbulent flow. The species used (Rhodototula mucilaginosa, Candida krusei, Candida kefyr and Candida tropicalis) were isolated from a clarified apple juice industry. The flow conditions impacted biofilm composition over time, with a predominance of C. krusei under static and turbulent flow. Likewise, structural variations occurred, with a tighter appearance under dynamic flow. Under turbulent flow there was an increase of 112 μm in biofilm thickness at 11 weeks (p < 0.001) and cell morphology was governed by hyphal structures and rounded cells. Using the in situ growth method introduced here, yeast biofilms were determined to be viscoelastic materials with a predominantly solid-like behavior, and neither this nor the G'0 values were significantly affected by the flow conditions or the growth time, and at large deformations their weak structure collapsed beyond a critical strain of about 1.5-5%. The present work could represent a starting point for developing in situ measurements of yeast rheology and contribute to a thin body of knowledge about fungal biofilm formation.

  9. Biopulsing: An in situ aeration remediation strategy

    SciTech Connect

    Gupta, H.S.; Marshall, T.R.

    1997-12-31

    In situ soil aeration is an accepted technology for remediation of soil and groundwater impacted with petroleum hydrocarbons and halogenated hydrocarbons. This technology was utilized for remediating soil and groundwater at an aerospace components manufacturing facility located in southern California, Soil and groundwater had been impacted at the facility from historical releases of petroleum and halogenated hydrocarbons. Innovations in remediation system design, installation and monitoring strategies are described in this paper. The following tasks were conducted; (1) evaluation of the extent of impacted soil and groundwater; (2) collection of site-specific data necessary to evaluate and implement an appropriate remediation system to address the hydrocarbon-impacted soil; and (3) design, installation and operation of an in situ aeration system for remediation of soil and groundwater. The in situ aeration system operates on the principles of bioventing. Air was injected weekly into the subsurface by a system of wells placed at selected locations in short pulses lasting several hours. Oxygen utilization in the subsurface was monitored using subsurface sensors. Subsurface oxygen utilization rates of up to 1.5 percent resulted in an estimate of mass reduction of 71 pounds of hydrocarbons. The concentration of halogenated hydrocarbons was reduced in groundwater following commencement of aeration was observed in subsequent sampling events. The contribution of vadose zone aeration in reducing the concentrations of halogenated hydrocarbons in groundwater is currently being evaluated.

  10. DEMONSTRATION BULLETIN: IN SITU ELECTROKINETIC EXTRACTION SYSTEM - SANDIA NATIONAL LABORATORIES

    EPA Science Inventory

    Sandia National Laboratories (SNL) has developed an in situ soil remediation system that uses electrokinetic principles to remediate hexavalent chromium-contaminated unsaturated or partially saturated soils. The technology involves the in situ application of direct current to the...

  11. DEMONSTRATION BULLETIN: IN SITU ELECTROKINETIC EXTRACTION SYSTEM - SANDIA NATIONAL LABORATORIES

    EPA Science Inventory

    Sandia National Laboratories (SNL) has developed an in situ soil remediation system that uses electrokinetic principles to remediate hexavalent chromium-contaminated unsaturated or partially saturated soils. The technology involves the in situ application of direct current to the...

  12. Considerations in Deciding to Treat Contaminated Unsaturated Soils In Situ

    EPA Pesticide Factsheets

    The purpose of this Issue Paper is to assist the user in deciding if in situ treatment of contaminated soil is a potentially feasible remedial alternative and to assist in the process of reviewing and screening in situ technologies.

  13. In situ synthesis studies of silicon clathrates

    NASA Astrophysics Data System (ADS)

    Hutchins, Peter Thomas

    Solid state clathrates have shown considerable potential as a new class of materials over the past 30 years. Experimental and theoretical studies have shown that precise tuning and synthetic control of these materials, may lead to desirable properties. Very little is known about the mechanism of formation of the clathrates and so the desire to have accurate synthetic control was, until now, unrealistic. This thesis address the problem using in situ synchrotron x-ray techniques. In this study, experiments were designed to utilise time-resolved in situ diffraction techniques and high temperature 23Na NMR, in efforts to understand the mechanism of formation for this class of expanded framework materials. A complex high vacuum capillary synthesis cell was designed for loading under inert conditions and operation under high vacuum at station 6.2 of the SRS Daresbury. The cell was designed to operate in conjunction with a custom made furnace capable of temperatures in excess of 1000 C, as well as a vacuum system capable of 10"5 bar. The clathrate system was studied in situ, using rapid data collection to elucidate the mechanism of formation. The data were analysed using Rietveld methods and showed a structural link between the monoclinic, C2/c, Zintl precursors and the cubic, Pm3n, clathrate I phase. The phases were found to be linked by relation of the sodium planes in the silicide and the sodium atoms resident at cages centres in the clathrate system. This evidence suggests the guest species is instrumental in formation of the clathrate structure by templating the formation of the cages in the structure. Solid state 23Na NMR was utilised to complete specially design experiments, similar to those complete in situ using synchrotron x-ray techniques. The experiments showed increased spherical symmetry of the alkali metal sites and suggested increased mobility of the guest atoms during heating. In addition, cyclic heating experiments using in situ diffraction showed

  14. TSSM: The in situ exploration of Titan

    NASA Astrophysics Data System (ADS)

    Coustenis, A.; Lunine, J. I.; Lebreton, J. P.; Matson, D.; Reh, K.; Beauchamp, P.; Erd, C.

    2008-09-01

    The Titan Saturn System Mission (TSSM) mission was born when NASA and ESA decided to collaborate on two missions independently selected by each agency: the Titan and Enceladus mission (TandEM), and Titan Explorer, a 2007 Flagship study. TandEM, the Titan and Enceladus mission, was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call. The mission concept is to perform remote and in situ investigations of Titan primarily, but also of Enceladus and Saturn's magentosphere. The two satellites are tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TSSM will study Titan as a system, including its upper atmosphere, the interactions with the magnetosphere, the neutral atmosphere, surface, interior, origin and evolution, as well as the astrobiological potential of Titan. It is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini- Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time for Titan, several close flybys of Enceladus). One overarching goal of the TSSM mission is to explore in situ the atmosphere and surface of Titan. In the current mission architecture, TSSM consists of an orbiter (under NASA's responsibility) with a large host of instruments which would perform several Enceladus and Titan flybys before stabilizing in an orbit around Titan alone, therein delivering in situ elements (a Montgolfière, or hot air balloon, and a probe/lander). The latter are being studied by ESA. The balloon will circumnavigate Titan above the equator at an altitude of about 10 km for several months. The

  15. In situ surface biodegradation of restorative materials.

    PubMed

    Padovani, Gc; Fúcio, Sbp; Ambrosano, Gmb; Sinhoreti, Mac; Puppin-Rontani, Rm

    2014-01-01

    SUMMARY This study aimed to evaluate the surface characteristics of restorative materials (roughness, hardness, chemical changes by energy-dispersive spectroscopy [EDX], and scanning electron microscopy [SEM]) submitted to in situ biodegradation. Fifteen discs of each material (IPS e.max [EM], Filtek Supreme [FS], Vitremer [VI], Ketac Molar Easymix [KM], and Amalgam GS-80 [AM]) were fabricated in a metallic mold (4.0 mm × 1.5 mm). Roughness, hardness, SEM, and EDX were then evaluated. Fifteen healthy volunteers used a palatal device containing one disc of each restorative material for seven days. After the biodegradation, the roughness, hardness, SEM, and EDX were once again evaluated. Data obtained from the roughness and hardness evaluations were submitted to Kolmogorov-Smirnov and Tukey-Kramer tests (p<0.05). All esthetic restorative materials showed a significant increase in the roughness after biodegradation. Before biodegradation, significant differences in the hardness among the materials were seen: EM>AM>FS>KM>VI. After biodegradation, the hardness was significantly altered among the materials studied: EM>AM>FS=KM>VI, along with a significant increase in the hardness for AM, KM, and VI. SEM images indicated degradation on the surface of all materials, showing porosities, cracks, and roughness. Furthermore, after biodegradation, FS showed the presence of Cl, K, and Ca on the surface, while F was not present on the VI and KM surfaces. EM and AM did not have alterations in their chemical composition after biodegradation. It was concluded that the dental biofilm accumulation in situ on different restorative materials is a material-dependent parameter. Overall, all materials changed after biodegradation: esthetic restorative materials showed increased roughness, confirmed by SEM, and the ionomer materials and silver amalgam showed a significantly higher hardness. Finally, the initial chemical composition of the composite resin and ionomer materials evaluated was

  16. In-Situ Wire Damage Detection System

    NASA Technical Reports Server (NTRS)

    Williams, Martha K. (Inventor); Roberson, Luke B. (Inventor); Tate, Lanetra C. (Inventor); Smith, Trent M. (Inventor); Gibson, Tracy L. (Inventor); Jolley, Scott T. (Inventor); Medelius, Pedro J. (Inventor)

    2014-01-01

    An in-situ system for detecting damage in an electrically conductive wire. The system includes a substrate at least partially covered by a layer of electrically conductive material forming a continuous or non-continuous electrically conductive layer connected to an electrical signal generator adapted to delivering electrical signals to the electrically conductive layer. Data is received and processed to identify damage to the substrate or electrically conductive layer. The electrically conductive material may include metalized carbon fibers, a thin metal coating, a conductive polymer, carbon nanotubes, metal nanoparticles or a combination thereof.

  17. Spatially controlled, in situ synthesis of polymers

    DOEpatents

    Caneba, Gerard T.; Tirumala, Vijaya Raghavan; Mancini, Derrick C.; Wang, Hsien-Hau

    2005-03-22

    An in situ polymer microstructure formation method. The monomer mixture is polymerized in a solvent/precipitant through exposure to ionizing radiation in the absence any chemical mediators. If an exposure mask is employed to block out certain regions of the radiation cross section, then a patterned microstructure is formed. The polymerization mechanism is based on the so-called free-radical retrograde-precipitation polymerization process, in which polymerization occurs while the system is phase separating above the lower critical solution temperature. This method was extended to produce a crosslinked line grid-pattern of poly (N-isopropylacrylamide), which has been known to have thermoreversible properties.

  18. In Situ Preservation of Historic Spacecraft

    NASA Astrophysics Data System (ADS)

    Barclay, R.; Brooks, R.

    The loss of the Mir space station is shown to symbolize a new consciousness of the value of space artefacts. The reasons why such artefacts as Mir become historic objects worthy of preservation are examined. Preservation of space vehicles in situ is discussed, with particular reference to safety, monitoring and long term costs. An argument is made for a wider definition for World Heritage designations to include material beyond the surface of the Earth, and for international bodies to assess, monitor and oversee these projects. Such heritage sites are seen as an economic driver for the development of space tourism in the 21st century.

  19. Environmental monitoring and in situ gamma spectrometry

    NASA Astrophysics Data System (ADS)

    Klusoň, J.

    2001-06-01

    In situ gamma ray spectrometry is widely used for monitoring of natural as well as man-made radionuclides and corresponding gamma fields in the environment or working places. It finds effective application in the operational and accidental monitoring of nuclear facilities and their vicinity, spent fuel storages and waste depositories, radioactive contamination measurements and mapping, environmental, radiohygienic and radiation safety studies, geological prospecting and mapping, etc. Progressive spectrometric methods based on scintillation and semiconductor spectrometry and spectral deconvolution are discussed, including experimental arrangement as well as detection system responses/response matrixes simulation using stochastic (Monte Carlo) models. Methods for ground-level and airborne measurements are presented.

  20. In situ viscometry by optical trapping interferometry

    NASA Astrophysics Data System (ADS)

    Guzmán, Camilo; Flyvbjerg, Henrik; Köszali, Roland; Ecoffet, Carole; Forró, László; Jeney, Sylvia

    2008-11-01

    We demonstrate quantitative in situ viscosity measurements by tracking the thermal fluctuations of an optically trapped microsphere subjected to a small oscillatory flow. The measured power spectral density of the sphere's positions displays a characteristic peak at the driving frequency of the flow, which is simply proportional to the viscosity, when measured in units of the thermal power spectral density at the same frequency. Measurements are validated on different water-glycerol mixtures, as well as in a glycerol gradient, where no a priori knowledge of the solution is used to determine the glycerol concentration.

  1. In situ characterization of undulator magnetic fields.

    PubMed

    Moreno, Thierry; Otero, Edwige; Ohresser, Philippe

    2012-03-01

    A new in situ method is proposed to characterize the peak magnetic fields of undulator sources. The X-ray beam emitted by the HU52 Apple-2 undulator of the DEIMOS beamline of the SOLEIL synchrotron is analyzed using the Bragg diffraction of a Si(111) crystal. Measurements over the undulator gap range in linear horizontal polarization are compared with simulations in order to rebuild the Halbach function linking the undulator gaps to their peak magnetic fields. The method presented also allows information about the electron beam to be obtained.

  2. In-situ calibration of capacitance monometers

    NASA Astrophysics Data System (ADS)

    Hartley, J. L.; Fuentes, E. C.

    Volumetric pressure division is a process of providing calculated test pressures beginning with an initial small volume of gas at high pressure and expanding into other known volumes. An in situ calibration using volumetric pressure division is described. Calibration performance is evaluated by using established manometer dial corrections in calculating the gas leak rate of a known leak rate standard. A difference of 0.7% is shown between the standard's mass spectrometer gas leak calibration and a gas leak measurement using the manometer dial corrections.

  3. In situ hydrogen loading on zirconium powder

    PubMed Central

    Maimaitiyili, Tuerdi; Blomqvist, Jakob; Steuwer, Axel; Bjerkén, Christina; Zanellato, Olivier; Blackmur, Matthew S.; Andrieux, Jérôme; Ribeiro, Fabienne

    2015-01-01

    For the first time, various hydride phases in a zirconium–hydrogen system have been prepared in a high-energy synchrotron X-ray radiation beamline and their transformation behaviour has been studied in situ. First, the formation and dissolution of hydrides in commercially pure zirconium powder were monitored in real time during hydrogenation and dehydrogenation, then whole pattern crystal structure analysis such as Rietveld and Pawley refinements were performed. All commonly reported low-pressure phases presented in the Zr–H phase diagram are obtained from a single experimental arrangement. PMID:26134803

  4. GAS TURBINE REHEAT USING IN SITU COMBUSTION

    SciTech Connect

    D.M. Bachovchin; T.E. Lippert; R.A. Newby P.G.A. Cizmas

    2004-05-17

    In situ reheat is an alternative to traditional gas turbine reheat design in which fuel is fed through airfoils rather than in a bulky discrete combustor separating HP and LP turbines. The goals are to achieve increased power output and/or efficiency without higher emissions. In this program the scientific basis for achieving burnout with low emissions has been explored. In Task 1, Blade Path Aerodynamics, design options were evaluated using CFD in terms of burnout, increase of power output, and possible hot streaking. It was concluded that Vane 1 injection in a conventional 4-stage turbine was preferred. Vane 2 injection after vane 1 injection was possible, but of marginal benefit. In Task 2, Combustion and Emissions, detailed chemical kinetics modeling, validated by Task 3, Sub-Scale Testing, experiments, resulted in the same conclusions, with the added conclusion that some increase in emissions was expected. In Task 4, Conceptual Design and Development Plan, Siemens Westinghouse power cycle analysis software was used to evaluate alternative in situ reheat design options. Only single stage reheat, via vane 1, was found to have merit, consistent with prior Tasks. Unifying the results of all the tasks, a conceptual design for single stage reheat utilizing 24 holes, 1.8 mm diameter, at the trailing edge of vane 1 is presented. A development plan is presented.

  5. Dosimetry of in situ activated dysprosium microspheres.

    PubMed

    Adnani, N

    2004-03-07

    This paper presents the results of a study aimed at investigating the dosimetry of stable dysprosium microspheres activated, in situ, by a linac generated photon beam. In phantom measurements of the neutron flux within an 18 MV photon beam were performed using CR-39 detectors and gold activation. The results were used in conjunction with a Monte Carlo computer simulation to investigate the dose distribution resulting from the activation of dysprosium (Dy) microspheres using an 18 MV photon beam. Different depths, lesion volumes and volume concentrations of microspheres are investigated. The linac lower collimator jaws are assumed completely closed to shield the tumour volume from the photon dose. Using a single AP field with 0 x 0 cm2 field size (closed jaws), a photon dose rate of 600 MU min(-1) and 80 cm SSD for 10 min, an average dose exceeding 1 Gy can be delivered to spherical lesions of 0.5 cm and higher diameter. The variation of the average dose with the size of the lesion reaches saturation for tumour volumes exceeding 1 cm in diameter. This report shows that the photon beam of a high-energy linac can be used to activate Dy microspheres in situ and, as a result, deliver a significant dose of beta radiation. Non-radioactive Dy microspheres do not have the toxicity and imaging problems associated with commercially available yttrium-90 based products.

  6. In situ stabilization of entrapped elemental mercury.

    PubMed

    Devasena, M; Nambi, Indumathi M

    2013-11-30

    Elemental mercury is a dense immiscible fluid which gets entrapped as residual mercury in the pore spaces of the subsurface during improper disposals and accidental spills. This paper investigates in situ stabilization of entrapped elemental mercury to mercury sulphide using aqueous sodium polysulphide solution. Batch experiments showed 100% conversion efficiency of elemental mercury to mercury sulphide in a period of 96 h with sodium polysulphide/elemental mercury molar ratio of 1. XRD analysis identified the precipitate formed as mercury sulphide. Micromodel experiments, with glass beads as porous media, further demonstrated in situ stabilization of entrapped mercury under different residual mercury saturations. It was found that in a period of 10 days, 10% of entrapped mercury was stabilized as mercury sulphide, 0.088% was removed as dissolved mercury and the remaining elemental mercury was retained in porous media encapsulated by the newly formed mercury sulphide precipitate. However, there was no leaching of mercury from the micromodel effluent once stabilization was achieved. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Molecular cytogenetics using fluorescence in situ hybridization

    SciTech Connect

    Gray, J.W.; Kuo, Wen-Lin; Lucas, J.; Pinkel, D.; Weier, H-U.; Yu, Loh-Chung.

    1990-12-07

    Fluorescence in situ hybridization (FISH) with chromosome-specific probes enables several new areas of cytogenetic investigation by allowing visual determination of the presence and normality of specific genetic sequences in single metaphase or interphase cells. in this approach, termed molecular cytogenetics, the genetic loci to be analyzed are made microscopically visible in single cells using in situ hybridization with nucleic acid probes specific to these loci. To accomplish this, the DNA in the target cells is made single stranded by thermal denaturation and incubated with single-stranded, chemically modified probe under conditions where the probe will anneal only with DNA sequences to which it has high DNA sequence homology. The bound probe is then made visible by treatment with a fluorescent reagent such as fluorescein that binds to the chemical modification carried by the probe. The DNA to which the probe does not bind is made visible by staining with a dye such as propidium iodide that fluoresces at a wavelength different from that of the reagent used for probe visualization. We show in this report that probes are now available that make this technique useful for biological dosimetry, prenatal diagnosis and cancer biology. 31 refs., 3 figs.

  8. Guidelines offered for in-situ bioremediation

    SciTech Connect

    Haggin, J.

    1993-11-22

    General guidelines for use in evaluating in-situ bioremediation projects have been proposed by a committee of the National Research Council (NRC). The three-step strategy, outlined by committee members at a workshop early this month in Washington, D.C., is a response to controversy surrounding bioremediation that, in the eyes of the committee, prevents the full potential of the technology from being realized. Controversy arises, in part, from the rapidly increasing number of vendors of bioremediation services that has resulted from availability of site-cleanup funding and ever-tightening environmental regulation. The committee elected to focus on two aspects of bioremediation in its deliberations. The first was to restrict its attention to in-situ decontamination, using microorganisms to remove contamination from groundwater and soils that remain in place. This leaves out the subjects of ocean-tanker spills, in-plant waste streams, and sludge treatment. The second was to provide guidance in determining the effectiveness of bioremediation. This paper discusses these two aspects.

  9. Inherently safe in situ uranium recovery.

    SciTech Connect

    Krumhansl, James Lee; Beauheim, Richard Louis; Brady, Patrick Vane; Arnold, Bill Walter; Kanney, Joseph F.; McKenna, Sean Andrew

    2009-05-01

    Expansion of uranium mining in the United States is a concern to some environmental groups and sovereign Native American Nations. An approach which may alleviate some problems is to develop inherently safe in situ uranium recovery ('ISR') technologies. Current ISR technology relies on chemical extraction of trace levels of uranium from aquifers that, once mined, can still contain dissolved uranium and other trace metals that are a health concern. Existing ISR operations are few in number; however, high uranium prices are driving the industry to consider expanding operations nation-wide. Environmental concerns and enforcement of the new 30 ppb uranium drinking water standard may make opening new mining operations more difficult and costly. Here we propose a technological fix: the development of inherently safe in situ recovery (ISISR) methods. The four central features of an ISISR approach are: (1) New 'green' leachants that break down predictably in the subsurface, leaving uranium, and associated trace metals, in an immobile form; (2) Post-leachant uranium/metals-immobilizing washes that provide a backup decontamination process; (3) An optimized well-field design that increases uranium recovery efficiency and minimizes excursions of contaminated water; and (4) A combined hydrologic/geochemical protocol for designing low-cost post-extraction long-term monitoring. ISISR would bring larger amounts of uranium to the surface, leave fewer toxic metals in the aquifer, and cost less to monitor safely - thus providing a 'win-win-win' solution to all stakeholders.

  10. In situ PEM fuel cell water measurements

    SciTech Connect

    Borup, Rodney L; Mukundan, Rangachary; Davey, John R; Spendelow, Jacob S; Hussey, Daniel S; Jacobson, David L; Arif, Muhammad

    2009-01-01

    Efficient PEM (Polymer Electrolyte Membrane) fuel cell performance requires effective water management. To achieve a deeper understanding of water transport and performance issues associated with water management, we have conducted in situ water examinations to help understand the effects of components and operations. High Frequency Resistance (HFR), AC Impedance and Neutron imaging were used to measure water content in operating fuel cells, with various conditions, including current density, relative humidity, inlet flows, flow orientation and variable Gas Diffusion Layer (GDL) properties. High resolution neutron radiography was used to image fuel cells during a variety of conditions. The effect of specific operating conditions, including flow direction (co-flow or counter-flow) was examined. Counter-flow operation was found to result in higher water content than co-flow operation, which correlates to lower membrane resistivity. A variety of cells were used to quantify the membrane water in situ during exposure to saturated gases, during fuel cell operation, and during hydrogen pump operation. The quantitative results show lower membrane water content than previous results suggested.

  11. Biophotonic in situ sensor for plant leaves

    SciTech Connect

    Conejo, Elian; Frangi, Jean-Pierre; Rosny, Gilles de

    2010-04-01

    Knowledge of the water concentration of plants can be helpful in several environmental and agricultural domains. There are many methods for the determination of water content in plant leaves; however, most of them give a relative moisture level or an analytical measure after a previous calibration procedure. Even for other biochemical compounds such as dry matter or chlorophyll, the measurement techniques could be destructive. For this reason, a nondestructive method has been developed to measure the biochemical compounds of a plant leaf, using an infrared spectroscopy technique. One important advantage is the simplicity of the device (RAdiometre portatif de Mesure In Situ, RAMIS) and its capability to perform measurements in situ. The prototype is a leaf-clip configuration and is made of LEDs at five wavelengths (656, 721, 843, 937, and 1550 nm), and a silicon/germanium photosensor. To compute the water content of vegetative leaves, the radiative transfer model PROSPECT was implemented. This model can accurately predict spectral transmittances in the 400 nm to 2500 nm spectral region as a function of the principal leaf biochemical contents: water, dry matter, and chlorophyll. Using the transmittance measured by RAMIS into an inversion procedure of PROSPECT: A Model of Leaf Optical Properties Spectra, we are able to compute the values of water contents that show an agreement with the water contents measured directly using dry weight procedures. This method is presented as a possibility to estimate other leaf biochemical compounds using appropriate wavelengths.

  12. In situ biodegradation of creosote contaminated soils

    SciTech Connect

    Nelson, M.D.; Maier, W.J.

    1996-11-01

    The Reilly Tar and Chemical operated a coal tar and wood processing plant on a 80 acre site from 1917 until plant closure in 1972. Reilly disposed of wastewater from the operation in a network of ditches which discharged into a swampy area south of the Reilly site. The contamination from these sources has migrated downward into the groundwater, contaminating the shallow aquifer underlying the site. Through multi-aquifer wells the contamination has entered deeper aquifers including the Prairie Duchien-Jordan aquifer. Ongoing pump and treat operations are not viewed as ecologically or economically sound long-term solutions. All parties agreed that programs to eliminate polluting materials at the source to speed the cleanup process and minimize the potential leakage of the pollutants into interconnected aquifers is desirable. In this connection, a study was completed to examine whether source materials can be eliminated by on site and/or in situ bioremediation. In order to engineer a bioremediation strategy which optimizes degradation rates it is extremely important to determine the rate limiting steps in the treatment process. The results of this study show that if sufficient oxygen can be provided, in situ bioremediation could be effective at reducing or eliminating offsite pollutant migration and effectively remove the sources of the groundwater contamination.

  13. Enzyme Engineering for In Situ Immobilization.

    PubMed

    Rehm, Fabian B H; Chen, Shuxiong; Rehm, Bernd H A

    2016-10-14

    Enzymes are used as biocatalysts in a vast range of industrial applications. Immobilization of enzymes to solid supports or their self-assembly into insoluble particles enhances their applicability by strongly improving properties such as stability in changing environments, re-usability and applicability in continuous biocatalytic processes. The possibility of co-immobilizing various functionally related enzymes involved in multistep synthesis, conversion or degradation reactions enables the design of multifunctional biocatalyst with enhanced performance compared to their soluble counterparts. This review provides a brief overview of up-to-date in vitro immobilization strategies while focusing on recent advances in enzyme engineering towards in situ self-assembly into insoluble particles. In situ self-assembly approaches include the bioengineering of bacteria to abundantly form enzymatically active inclusion bodies such as enzyme inclusions or enzyme-coated polyhydroxyalkanoate granules. These one-step production strategies for immobilized enzymes avoid prefabrication of the carrier as well as chemical cross-linking or attachment to a support material while the controlled oriented display strongly enhances the fraction of accessible catalytic sites and hence functional enzymes.

  14. Biophotonic in situ sensor for plant leaves.

    PubMed

    Conejo, Elian; Frangi, Jean-Pierre; de Rosny, Gilles

    2010-04-01

    Knowledge of the water concentration of plants can be helpful in several environmental and agricultural domains. There are many methods for the determination of water content in plant leaves; however, most of them give a relative moisture level or an analytical measure after a previous calibration procedure. Even for other biochemical compounds such as dry matter or chlorophyll, the measurement techniques could be destructive. For this reason, a nondestructive method has been developed to measure the biochemical compounds of a plant leaf, using an infrared spectroscopy technique. One important advantage is the simplicity of the device (RAdiomètre portatif de Mesure In Situ, RAMIS) and its capability to perform measurements in situ. The prototype is a leaf-clip configuration and is made of LEDs at five wavelengths (656, 721, 843, 937, and 1550 nm), and a silicon/germanium photosensor. To compute the water content of vegetative leaves, the radiative transfer model PROSPECT was implemented. This model can accurately predict spectral transmittances in the 400 nm to 2500 nm spectral region as a function of the principal leaf biochemical contents: water, dry matter, and chlorophyll. Using the transmittance measured by RAMIS into an inversion procedure of A Model of Leaf Optical Properties Spectra, we are able to compute the values of water contents that show an agreement with the water contents measured directly using dry weight procedures. This method is presented as a possibility to estimate other leaf biochemical compounds using appropriate wavelengths.

  15. Natural attenuation processes during in situ capping.

    PubMed

    Himmelheber, David W; Pennell, Kurt D; Hughes, Joseph B

    2007-08-01

    Chlorinated solvents are common groundwater contaminants that threaten surface water quality and benthic health when present in groundwater seeps. Aquatic sediments can act as natural biobarriers to detoxify chlorinated solvent plumes via reductive dechlorination. In situ sediment capping, a remedial technique in which clean material is placed at the sediment-water interface, may alter sedimentary natural attenuation processes. This research explores the potential of Anacostia River sediment to naturally attenuate chlorinated solvents under simulated capping conditions. Results of microcosm studies demonstrated that intrinsic dechlorination of dissolved-phase PCE to ethene was possible, with electron donor availability controlling microbial activity. A diverse microbial community was present in the sediment, including multiple Dehalococcoides strains indicated by the amplification of the reductive dehalogenases tceA, vcrA, and bvcA. An upflow column simulating a capped sediment bed subject to PCE-contaminated groundwater seepage lost dechlorination activity with time and only achieved complete dechlorination when microorganisms present in the sediment were provided electron donor. Increases in effluent chloroethene concentrations during the period of biostimulation were attributed to biologically enhanced desorption and the formation of less sorptive dechlorination products. These findings suggest that in situ caps should be designed to account for reductions in natural biobarrier reactivity and for the potential breakthrough of groundwater contaminants.

  16. In Situ Instruments: Overview of In Situ Instruments for Deployment in Extreme Environments

    NASA Technical Reports Server (NTRS)

    Taylor, M.; Cardell, G.

    2000-01-01

    This presentation reviews the design and specifications for several instruments for deployment in extreme environments. The instruments are: (1) In Situ Geochronology Instrument, (2) Laser Ablation Sampling Instrument, (3) Micro Hygrometer (4) Micro Lidar, (5) Atmospheric Electron X-Ray Spectrometer and (6) Nuclear Magnetic Resonance Spectrometer. Included in the descriptions are the contact people and the objective of each instrument.

  17. High resolution in situ ultrasonic corrosion monitor

    DOEpatents

    Grossman, R.J.

    1984-01-10

    An ultrasonic corrosion monitor is provided which produces an in situ measurement of the amount of corrosion of a monitoring zone or zones of an elongate probe placed in the corrosive environment. A monitoring zone is preferably formed between the end of the probe and the junction of the zone with a lead-in portion of the probe. Ultrasonic pulses are applied to the probe and a determination made of the time interval between pulses reflected from the end of the probe and the junction referred to, both when the probe is uncorroded and while it is corroding. Corresponding electrical signals are produced and a value for the normalized transit time delay derived from these time interval measurements is used to calculate the amount of corrosion.

  18. High resolution in situ ultrasonic corrosion monitor

    DOEpatents

    Grossman, Robert J.

    1985-01-01

    An ultrasonic corrosion monitor is provided which produces an in situ measurement of the amount of corrosion of a monitoring zone or zones of an elongate probe placed in the corrosive environment. A monitoring zone is preferably formed between the end of the probe and the junction of the zone with a lead-in portion of the probe. Ultrasonic pulses are applied to the probe and a determination made of the time interval between pulses reflected from the end of the probe and the junction referred to, both when the probe is uncorroded and while it is corroding. Corresponding electrical signals are produced and a value for the normalized transit time delay derived from these time interval measurements is used to calculate the amount of corrosion.

  19. Remote versus in situ turbulence measurements

    NASA Technical Reports Server (NTRS)

    Frost, Walter

    1987-01-01

    Comparisons of in situ wind and turbulence measurements made with the NASA B-57 instrumented aircraft and those remotely made with both radar and lidar systems are presented. Turbulence measurements with a lidar or radar system as compared with those from an aircraft are the principal themes. However, some discussion of mean wind speed and direction measurements is presented. First, the principle of measuring turbulence with Doppler lidar and radar is briefly and conceptually described. The comparisons with aircraft measurements are then discussed. Two studies in particular are addressed: one uses the JAWS Doppler radar data and the other uses data gathered both with the NASA Marshall Space Flight Center and the the NOAA Wave Propagation Lab. gound based lidars. Finally, some conclusions and recommendations are made.

  20. In situ PEM fuel cell water measurements

    SciTech Connect

    Borup, Rodney L; Mukundan, Rangachary; Davey, John R; Spendalow, Jacob S

    2008-01-01

    Efficient PEM fuel cell performance requires effective water management. The materials used, their durability, and the operating conditions under which fuel cells run, make efficient water management within a practical fuel cell system a primary challenge in developing commercially viable systems. We present experimental measurements of water content within operating fuel cells. in response to operational conditions, including transients and freezing conditions. To help understand the effect of components and operations, we examine water transport in operating fuel cells, measure the fuel cell water in situ and model the water transport within the fuel cell. High Frequency Resistance (HFR), AC Impedance and Neutron imaging (using NIST's facilities) were used to measure water content in operating fuel cells with various conditions, including current density, relative humidity, inlet flows, flow orientation and variable GDL properties. Ice formation in freezing cells was also monitored both during operation and shut-down conditions.

  1. Mars in Situ Resource Utilization Technology Evaluation

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.; Santago-Maldonado, Edgardo

    2012-01-01

    We have examined the technologies required to enable Mars In-Situ Resource Utilization (ISRU) because our understanding of Mars resources has changed significantly in the last five years as a result of recent robotic missions to the red planet. Two major developments, (1) confirmation of the presence of near-surface water in the form of ice in very large amounts at high latitudes by the Phoenix Lander and (2) the likely existence of water at lower latitudes in the form of hydrates or ice in the top one meter of the regolith, have the potential to change ISRU technology selection. A brief technology assessment was performed for the most promising Mars atmospheric gas processing techniques: Reverse Water Gas Shift (RWGS) and Methanation (aka Sabatier), as well as an overview of soil processing technology to extract water from Martian soil.

  2. Direct in situ measurements of thermospheric temperature

    NASA Technical Reports Server (NTRS)

    Kayser, D. C.; Nier, A. O.; Breig, E. L.; Power, R. A.; Hanson, W. B.

    1979-01-01

    The open source neutral mass spectrometer on the Atmosphere Explorer satellites used for direct in situ measurements of the neutral gas temperature by means of the 'fly-through' mode of operation is evaluated. The derived neutral temperature (Tn) is compared with ion temperatures (T1) obtained simultaneously from the on-board retarding potential analyzer for altitudes and conditions where the two temperatures should be equal. A statistical analysis showed consistency between concurrently observed values of Tn and T1, also shown through profiles depicting their altitude distributions between 150 and 225 km. The overall magnitude of temperatures calculated from the Jacchia (1971) model results in a better representation of the observations than the higher temperatures predicted for this region by the MSIS model (Hedin, 1977), and agreement is also found between observed temperatures and neutral temperatures derived from altitude distributions of N2 particle densities.

  3. Condition of in situ unexploded ordnance.

    PubMed

    Taylor, Susan; Bigl, Susan; Packer, Bonnie

    2015-02-01

    Unexploded ordnance (UXO) become point contamination sources when their casings fail and their explosive fill dissolve. To determine the modes of failure, we documented the condition of UXO found on military training ranges and sampled soils for explosives beneath 42 in situ UXO. We found that oxidation caused the metal UXO casings to swell and fail catastrophically. Unlike previous work, pitting of the metal casings was not found to be an important release route for explosives. Of the 42 UXO sampled, eight were leaking explosives into the soil and of these, four had perforated or cracked casings, three were corroded and one was a partially detonated round. We estimated a surface density of 74 UXO per hectare for a subset of UXO sampled. We used the relative concentrations of explosives and their transformation products in the soil to determine if the explosives had recently dissolved or were from past military training.

  4. In situ Fabrication of Monolithic Copper Azide

    NASA Astrophysics Data System (ADS)

    Li, Bing; Li, Mingyu; Zeng, Qingxuan; Wu, Xingyu

    2016-04-01

    Fabrication and characterization of monolithic copper azide were performed. The monolithic nanoporous copper (NPC) with interconnected pores and nanoparticles was prepared by decomposition and sintering of the ultrafine copper oxalate. The preferable monolithic NPC can be obtained through decomposition and sintering at 400°C for 30 min. Then, the available monolithic NPC was in situ reacted with the gaseous HN3 for 24 h and the monolithic NPC was transformed into monolithic copper azide. Additionally, the copper particles prepared by electrodeposition were also reacted with the gaseous HN3 under uniform conditions as a comparison. The fabricated monolithic copper azide was characterized by Fourier transform infrared (FTIR), inductively coupled plasma-optical emission spectrometry (ICP-OES), and differential scanning calorimetry (DSC).

  5. In Situ Burning of Oil Spills.

    PubMed

    Evans, D D; Mulholland, G W; Baum, H R; Walton, W D; McGrattan, K B

    2001-01-01

    For more than a decade NIST conducted research to understand, measure and predict the important features of burning oil on water. Results of that research have been included in nationally recognized guidelines for approval of intentional burning. NIST measurements and predictions have played a major role in establishing in situ burning as a primary oil spill response method. Data are given for pool fire burning rates, smoke yield, smoke particulate size distribution, smoke aging, and polycyclic aromatic hydrocarbon content of the smoke for crude and fuel oil fires with effective diameters up to 17.2 m. New user-friendly software, ALOFT, was developed to quantify the large-scale features and trajectory of wind blown smoke plumes in the atmosphere and estimate the ground level smoke particulate concentrations. Predictions using the model were tested successfully against data from large-scale tests. ALOFT software is being used by oil spill response teams to help assess the potential impact of intentional burning.

  6. Recent advances in in situ vitrification

    SciTech Connect

    Bonner, W.F.; Luey, Ja-Kael.

    1992-05-01

    In Situ Vitrification (ISV) is an innovative mobile remediation technology for soils and other underground contamination: Developed by the US Department of Energy's Pacific Northwest Laboratory (PNL), ISV has advanced during the past decade from a laboratory concept to a remediation technology commercially available for contaminated soils. ISV technology is currently being developed for remediation of DOE waste sites at Hanford, Oak Ridge National Laboratory (ORNL) Idaho National Laboratory (INEL), and other sites. The incentives for application of ISV can convert contaminated sites to a solid, highly durable block similar to naturally occurring obsidian. The ISV product has been shown capable of passing US Environmental Protection Agency (EPA) tests such as the Toxic Characteristic Leach Procedure (TCLP). Retrieval, handling and transport of untreated hazardous material would normally not be required after application of ISV. Therefore, costs, exposure to personnel, risk of releases to the environment, and generation of secondary wastes are greatly reduced compared with remove-and-treat technologies.

  7. Recent advances in in situ vitrification

    SciTech Connect

    Bonner, W.F.; Luey, Ja-Kael

    1992-05-01

    In Situ Vitrification (ISV) is an innovative mobile remediation technology for soils and other underground contamination: Developed by the US Department of Energy`s Pacific Northwest Laboratory (PNL), ISV has advanced during the past decade from a laboratory concept to a remediation technology commercially available for contaminated soils. ISV technology is currently being developed for remediation of DOE waste sites at Hanford, Oak Ridge National Laboratory (ORNL) Idaho National Laboratory (INEL), and other sites. The incentives for application of ISV can convert contaminated sites to a solid, highly durable block similar to naturally occurring obsidian. The ISV product has been shown capable of passing US Environmental Protection Agency (EPA) tests such as the Toxic Characteristic Leach Procedure (TCLP). Retrieval, handling and transport of untreated hazardous material would normally not be required after application of ISV. Therefore, costs, exposure to personnel, risk of releases to the environment, and generation of secondary wastes are greatly reduced compared with remove-and-treat technologies.

  8. Support Routines for In Situ Image Processing

    NASA Technical Reports Server (NTRS)

    Deen, Robert G.; Pariser, Oleg; Yeates, Matthew C.; Lee, Hyun H.; Lorre, Jean

    2013-01-01

    This software consists of a set of application programs that support ground-based image processing for in situ missions. These programs represent a collection of utility routines that perform miscellaneous functions in the context of the ground data system. Each one fulfills some specific need as determined via operational experience. The most unique aspect to these programs is that they are integrated into the large, in situ image processing system via the PIG (Planetary Image Geometry) library. They work directly with space in situ data, understanding the appropriate image meta-data fields and updating them properly. The programs themselves are completely multimission; all mission dependencies are handled by PIG. This suite of programs consists of: (1)marscahv: Generates a linearized, epi-polar aligned image given a stereo pair of images. These images are optimized for 1-D stereo correlations, (2) marscheckcm: Compares the camera model in an image label with one derived via kinematics modeling on the ground, (3) marschkovl: Checks the overlaps between a list of images in order to determine which might be stereo pairs. This is useful for non-traditional stereo images like long-baseline or those from an articulating arm camera, (4) marscoordtrans: Translates mosaic coordinates from one form into another, (5) marsdispcompare: Checks a Left Right stereo disparity image against a Right Left disparity image to ensure they are consistent with each other, (6) marsdispwarp: Takes one image of a stereo pair and warps it through a disparity map to create a synthetic opposite- eye image. For example, a right eye image could be transformed to look like it was taken from the left eye via this program, (7) marsfidfinder: Finds fiducial markers in an image by projecting their approximate location and then using correlation to locate the markers to subpixel accuracy. These fiducial markets are small targets attached to the spacecraft surface. This helps verify, or improve, the

  9. IN SITU URANIUM STABILIZATION BY MICROBIAL METABOLITES

    SciTech Connect

    Turick, C; Anna Knox, A; Chad L Leverette,C; Yianne Kritzas, Y

    2006-11-29

    Soil contaminated with U was the focus of this study in order to develop in-situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE) Savannah River Site (SRS) as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >106 cells/g wet soil. Pyomelanin demonstrated U chelating and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in field tests demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.

  10. Semiconductors: In Situ Processing of Photovoltaic Devices

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.

    1998-01-01

    Current proposals for developing an extended human presence on the Moon and Mars increasingly consider the processing of nonterrestrial materials essential for keeping the Earth launch burden reasonable. Utilization of in situ resources for construction of lunar and Mars bases will initially require assessment of resource availability followed by the development of economically acceptable and technically feasible extraction processes. In regard to materials processing and fabrication, the lower gravity level on the Moon (0.125 g) and Mars (0.367 g) will dramatically change the presently accepted hierarchy of materials in terms of specific properties, a factor that must be understood and exploited. Furthermore, significant changes are expected in the behavior of liquid materials during processing. In casting, for example, mold filling and associated solidification processes have to be reevaluated. Finally, microstructural development, and therefore material properties, presently being documented through ongoing research in microgravity science and applications, need to be understood and scaled to the reduced gravity environments.

  11. In situ hybridization of suprachiasmatic nucleus slices.

    PubMed

    de la Iglesia, Horacio O

    2007-01-01

    The progress in the understanding of the molecular machinery of mammalian circadian clocks, in combination with the well-established role of the hypothalamic suprachiasmatic nucleus (SCN) as a master circadian clock, has provided an invaluable system for the study of the molecular basis of circadian rhythmicity. Using in situ hybridization (ISH) techniques that label specific clock-gene mRNAs within the SCN, researchers can now elucidate the core molecular oscillatory mechanisms underlying specific circadian physiological and behavioral phenotypes. In this chapter, two methods for ISH within the SCN are described. The first method is based on the fluorescent labeling of mRNA and is suitable for confocal microscopy analysis and double labeling techniques. The second method is based on the radioactive labeling of mRNA and is more sensitive and more adequate for the relative quantification of mRNA species.

  12. Thermal aggregation of patatin studied in situ.

    PubMed

    Pots, A M; ten Grotenhuis, E; Gruppen, H; Voragen, A G; de Kruif, K G

    1999-11-01

    In this work dynamic light scattering was used to study the thermal aggregation of patatin in situ, to elucidate the physical aggregation mechanism of the protein and to be able to relate the aggregation behavior to its structural properties. The dependence of the aggregation rates on the temperature and the ionic strength suggested a mechanism of slow coagulation, being both diffusion and chemically limited. The aggregation rate dependence on the protein concentration was in accordance with the mechanism proposed. The aggregation rates as obtained at temperatures ranging from 40 to 65 degrees C correlated well with unfolding of the protein at a secondary level. Small-angle neutron scattering and dynamic light scattering results were in good accordance; they revealed that native patatin has a cylindrical shape with a diameter and length of 5 and 9.8 nm, respectively.

  13. In situ soil remediation: Bacteria or fungi?

    SciTech Connect

    Cutright, T.J.; Lee, S.

    1995-07-01

    Contamination of the environment is not a new problem. For most of recorded history, the unwanted byproducts of industrial and residential processes have been dumped into unlined pits or nearby streams. Although disposal techniques have greatly improved, significant quantities of hazardous materials are still being released to the environment via accidental spills and leaking underground storage tanks. One particular group of contaminants of critical environmental concern is polycyclic aromatic hydrocarbons (PAHs). PAH-contaminated sites typically cover large areas; therefore, the development of in situ remediation techniques such as bioremediation is strongly emphasized. In situations when inherent microorganisms are not capable of degrading the contaminants, foreign strains must be used. Bioremediation experiments were conducted to compare the remediation efficiencies of a bacteria and a fungus for an industrially PAH contaminated soil. Specifically, the use of three supplemental nutrient solutions were investigated in conjunction with the bacteria Achromobacter sp. and fungus Cunninghamella echinulata var. elegans.

  14. In-situ Resources In Space

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.

    2005-01-01

    This tutorial is a primer on the motivational and materials science basis for utilizing space resources to lower the cost and increase the safety and reliability of human systems beyond Earth's orbit. Past research in materials processing in orbit will be briefly reviewed to emphasize the challenges and advantages inherent in processing materials in space. Data on resource availability from human Lunar and robotic/sensor missions beyond the Moon will be overviewed for resource relevance to human exploration and development of space. Specific scenarios such as propellant production on the Moon and Mars, and lunar photovoltaic power production from in-situ materials will be discussed in relation to exploration and commercialization of space. A conclusion will cover some of the visionary proposals for the use of space resources to extend human society and prosperity beyond Earth.

  15. In-situ Resources In Space

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.

    2005-01-01

    This tutorial is a primer on the motivational and materials science basis for utilizing space resources to lower the cost and increase the safety and reliability of human systems beyond Earth's orbit. Past research in materials processing in orbit will be briefly reviewed to emphasize the challenges and advantages inherent in processing materials in space. Data on resource availability from human Lunar and robotic/sensor missions beyond the Moon will be overviewed for resource relevance to human exploration and development of space. Specific scenarios such as propellant production on the Moon and Mars, and lunar photovoltaic power production from in-situ materials will be discussed in relation to exploration and commercialization of space. A conclusion will cover some of the visionary proposals for the use of space resources to extend human society and prosperity beyond Earth.

  16. In-situ continuous water monitoring system

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1998-01-01

    An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer.

  17. In-situ continuous water monitoring system

    DOEpatents

    Thompson, C.V.; Wise, M.B.

    1998-03-31

    An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer. 2 figs.

  18. In-situ continuous water analyzing module

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1998-01-01

    An in-situ continuous liquid analyzing system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectometer and the volatile components are continuously analyzed by the mass spectrometer.

  19. In situ secondary ion mass spectrometry analysis

    SciTech Connect

    Groenewold, G.S.; Applehans, A.D.; Ingram, J.C.; Delmore, J.E.; Dahl, D.A.

    1993-01-01

    The direct detection of tributyl phosphate (TBP) on rocks using molecular beam surface analysis [MBSA or in situ secondary ion mass spectrometry (SIMS)] is demonstrated. Quantities as low as 250 ng were detected on basalt and sandstone with little or no sample preparation. Detection of TBP on soil has proven to be more problematic and requires further study. Ethylenediaminetetraacetic acid (EDTA) is more difficult to detect because it is very reactive with surfaces of interest. Nevertheless, it is possible to detect EDTA if the acidity of the surface is controlled. The detection of EDTA-metal complexes is currently an open question, but evidence is presented for the detection of ions arising from a EDTA-lead complex. Carboxylic acids (i.e., citric, ascorbic, malic, succinic, malonic, and oxalic) give characteristic SIM spectra, but their detection on sample surfaces awaits evaluation.

  20. In-situ trainable intrusion detection system

    DOEpatents

    Symons, Christopher T.; Beaver, Justin M.; Gillen, Rob; Potok, Thomas E.

    2016-11-15

    A computer implemented method detects intrusions using a computer by analyzing network traffic. The method includes a semi-supervised learning module connected to a network node. The learning module uses labeled and unlabeled data to train a semi-supervised machine learning sensor. The method records events that include a feature set made up of unauthorized intrusions and benign computer requests. The method identifies at least some of the benign computer requests that occur during the recording of the events while treating the remainder of the data as unlabeled. The method trains the semi-supervised learning module at the network node in-situ, such that the semi-supervised learning modules may identify malicious traffic without relying on specific rules, signatures, or anomaly detection.

  1. In situ exploration of large dynamic networks.

    PubMed

    Hadlak, Steffen; Schulz, Hans-Jörg; Schumann, Heidrun

    2011-12-01

    The analysis of large dynamic networks poses a challenge in many fields, ranging from large bot-nets to social networks. As dynamic networks exhibit different characteristics, e.g., being of sparse or dense structure, or having a continuous or discrete time line, a variety of visualization techniques have been specifically designed to handle these different aspects of network structure and time. This wide range of existing techniques is well justified, as rarely a single visualization is suitable to cover the entire visual analysis. Instead, visual representations are often switched in the course of the exploration of dynamic graphs as the focus of analysis shifts between the temporal and the structural aspects of the data. To support such a switching in a seamless and intuitive manner, we introduce the concept of in situ visualization--a novel strategy that tightly integrates existing visualization techniques for dynamic networks. It does so by allowing the user to interactively select in a base visualization a region for which a different visualization technique is then applied and embedded in the selection made. This permits to change the way a locally selected group of data items, such as nodes or time points, are shown--right in the place where they are positioned, thus supporting the user's overall mental map. Using this approach, a user can switch seamlessly between different visual representations to adapt a region of a base visualization to the specifics of the data within it or to the current analysis focus. This paper presents and discusses the in situ visualization strategy and its implications for dynamic graph visualization. Furthermore, it illustrates its usefulness by employing it for the visual exploration of dynamic networks from two different fields: model versioning and wireless mesh networks.

  2. In Situ Field Testing of Processes

    SciTech Connect

    J. Wang

    2001-12-14

    The purpose of this Analysis/Model Report (AMR) is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts of the Yucca Mountain Site Characterization Project (YMP). This revision updates data and analyses presented in the initial issue of this AMR. This AMR was developed in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' and ''Technical Work Plan for UZ Flow, Transport, and Coupled Processes Process Model Report. These activities were performed to investigate in situ flow and transport processes. The evaluations provide the necessary framework to: (1) refine and confirm the conceptual model of matrix and fracture processes in the unsaturated zone (UZ) and (2) analyze the impact of excavation (including use of construction water and effect of ventilation) on the UZ flow and transport processes. This AMR is intended to support revisions to ''Conceptual and Numerical Models for UZ Flow and Transport'' and ''Unsaturated Zone Flow and Transport Model Process Model Report''. In general, the results discussed in this AMR are from studies conducted using a combination or a subset of the following three approaches: (1) air-injection tests, (2) liquid-release tests, and (3) moisture monitoring using in-drift sensors or in-borehole sensors, to evaluate the impact of excavation, ventilation, and construction-water usage on the surrounding rocks. The liquid-release tests and air-injection tests provide an evaluation of in situ fracture flow and the competing processes of matrix imbibition. Only the findings from testing and data not covered in the ''Seepage Calibration Model and Seepage Testing Data'' are analyzed in detail in the AMR.

  3. Fungal biodegradation of phthalate plasticizer in situ.

    PubMed

    Pradeep, S; Faseela, P; Josh, M K Sarath; Balachandran, S; Devi, R Sudha; Benjamin, Sailas

    2013-04-01

    This unique study describes how Aspergillus japonicus, Penicillium brocae and Purpureocillium lilacinum, three novel isolates of our laboratory from heavily plastics-contaminated soil completely utilized the plasticizer di(2-ethylhexyl)phthalate (DEHP) bound to PVC blood storage bags (BB) in simple basal salt medium (BSM) by static submerged growth (28 °C). Initial quantification as well as percentage utilization of DEHP blended to BB were estimated periodically by extracting it into n-hexane. A two-stage cultivation strategy was employed for the complete mycoremediation of DEHP from BB in situ. During the first growth stage, about two-third parts of total (33.5% w/w) DEHP bound to BB were utilized in two weeks, accompanied by increased fungal biomass (~0.15-0.32 g per g BB) and sharp declining (to ~3) of initial pH (7.2). At this stagnant growth state (low pH), spent medium was replaced by fresh BSM (pH, 7.2), and thus in the second stage the remaining DEHP (one-third) in BB was utilized completely. The ditches and furrows seen from the topology of the BB as seen by the 3D AFM image further confirmed the bioremediation of DEHP physically bound to BB in situ. Of the three mycelial fungi employed, P. lilacinum independently showed highest efficiency for the complete utilization of DEHP bound to BB, whose activity was comparable to that of the consortium comprising all the three fungi described herein. To sum up, the two-stage cultivation strategy demonstrated in this study shows that a batch process would efficiently remediate the phthalic acid esters blended in plastics on a large scale, and thus it offers potentials for the management of plastics wastes.

  4. PERFORMANCE CONFIRMATION IN-SITU INSTRUMENTATION

    SciTech Connect

    N.T. Raczka

    2000-05-23

    The purpose of this document is to identify and analyze the types of in-situ instruments and methods that could be used in support of the data acquisition portion of the Performance Confirmation (PC) program at the potential nuclear waste repository at Yucca Mountain. The PC program will require geomechanical , geophysical, thermal, and hydrologic instrumentation of several kinds. This analysis is being prepared to document the technical issues associated with each type of measurement during the PC period. This analysis utilizes the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a) as its starting point. The scope of this analysis is primarily on the period after the start of waste package emplacement and before permanent closure of the repository, a period lasting between 15 and 300 years after last package emplacement (Stroupe 2000, Attachment 1, p. 1). The primary objectives of this analysis are to: (1) Review the design criteria as presented in the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a). The scope of this analysis will be limited to the instrumentation related to parameters that require continuous monitoring of the conditions underground. (2) Preliminary identification and listing of the data requirements and parameters as related to the current repository layout in support of PC monitoring. (3) Preliminary identification of methods and instrumentation for the acquisition of the required data. Although the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a) defines a broad range of data that must be obtained from a variety of methods, the focus of this analysis is on instrumentation related to the performance of the rock mass and the formation of water in the repository environment, that is obtainable from in-situ observation, testing, and monitoring.

  5. A novel in situ trigger combination method

    DOE PAGES

    Buzatu, Adrian; Warburton, Andreas; Krumnack, Nils; ...

    2013-01-30

    Searches for rare physics processes using particle detectors in high-luminosity colliding hadronic beam environments require the use of multi-level trigger systems to reject colossal background rates in real time. In analyses like the search for the Higgs boson, there is a need to maximize the signal acceptance by combining multiple different trigger chains when forming the offline data sample. In such statistically limited searches, datasets are often amassed over periods of several years, during which the trigger characteristics evolve and system performance can vary significantly. Reliable production cross-section measurements and upper limits must take into account a detailed understanding ofmore » the effective trigger inefficiency for every selected candidate event. We present as an example the complex situation of three trigger chains, based on missing energy and jet energy, that were combined in the context of the search for the Higgs (H) boson produced in association with a $W$ boson at the Collider Detector at Fermilab (CDF). We briefly review the existing techniques for combining triggers, namely the inclusion, division, and exclusion methods. We introduce and describe a novel fourth in situ method whereby, for each candidate event, only the trigger chain with the highest a priori probability of selecting the event is considered. We compare the inclusion and novel in situ methods for signal event yields in the CDF $WH$ search. This new combination method, by virtue of its scalability to large numbers of differing trigger chains and insensitivity to correlations between triggers, will benefit future long-running collider experiments, including those currently operating on the Large Hadron Collider.« less

  6. Field Applications of In Situ Remediation Technologies: Permeable Reactive Barriers

    DTIC Science & Technology

    2002-01-01

    Field Applications of In Situ Remediation Technologies: Permeable Reactive Barriers United States Environmental Protection Agency PRB Remediated... Applications of In Situ Remediation Technologies: Permeable Reactive Barriers 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Field Applications of In Situ Remediation Technologies

  7. DNA/DNA in situ hybridization with enzyme linked probes

    SciTech Connect

    Grillo, S.; Mosher, M.; Charles, P.; Henry, S.; Taub, F.

    1987-05-01

    A non-radioactive in situ nucleic acid hybridization method which requires no antibodies, haptens, avidin or biotin intermediateries is presented. Horseradish peroxidase (HRP) labeled nucleic acid probes are hybridized in situ for 2 hours or less, followed by brief washing of hybridized cells and the direct detection of in situ hybrids with diaminobenzidine (DAB). Application of this method to the detection of Human Papilloma Virus (HPV) in human cells is shown.

  8. Freeprocessing: Transparent in situ visualization via data interception

    PubMed Central

    Fogal, Thomas; Proch, Fabian; Schiewe, Alexander; Hasemann, Olaf; Kempf, Andreas; Krüger, Jens

    2014-01-01

    In situ visualization has become a popular method for avoiding the slowest component of many visualization pipelines: reading data from disk. Most previous in situ work has focused on achieving visualization scalability on par with simulation codes, or on the data movement concerns that become prevalent at extreme scales. In this work, we consider in situ analysis with respect to ease of use and programmability. We describe an abstraction that opens up new applications for in situ visualization, and demonstrate that this abstraction and an expanded set of use cases can be realized without a performance cost. PMID:25995996

  9. In situ DNA-hybridization chain reaction (HCR): a facilitated in situ HCR system for the detection of environmental microorganisms.

    PubMed

    Yamaguchi, Tsuyoshi; Kawakami, Shuji; Hatamoto, Masashi; Imachi, Hiroyuki; Takahashi, Masanobu; Araki, Nobuo; Yamaguchi, Takashi; Kubota, Kengo

    2015-07-01

    In situ detection of microorganisms by fluorescence in situ hybridization (FISH) is a powerful tool for environmental microbiology, but analyses can be hampered by low rRNA content in target organisms, especially in oligotrophic environments. Here, we present a non-enzymatic, hybridization chain reaction (HCR)-based signal amplified in situ whole-cell detection technique (in situ DNA-HCR). The components of the amplification buffer were optimized to polymerize DNA amplifier probes for in situ DNA-HCR. In situ hybridization of initiator probes followed by signal amplification via HCR produced bright signals with high specificity and probe permeation into cells. The detection rates for Bacteria in a seawater sample and Archaea in anaerobic sludge samples were comparable with or greater than those obtained by catalyzed reporter deposition (CARD)-FISH or standard FISH. Detection of multiple organisms (Bacteria, Archaea and Methanosaetaceae) in an anaerobic sludge sample was achieved by simultaneous in situ DNA-HCR. In summary, in situ DNA-HCR is a simple and easy technique for detecting single microbial cells and enhancing understanding of the ecology and behaviour of environmental microorganisms in situ. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. IN-SITU TRITIUM BETA DETECTOR

    SciTech Connect

    J.W. Berthold; L.A. Jeffers

    1998-04-15

    The objectives of this three-phase project were to design, develop, and demonstrate a monitoring system capable of detecting and quantifying tritium in situ in ground and surface waters, and in water from effluent lines prior to discharge into public waterways. The tritium detection system design is based on measurement of the low energy beta radiation from the radioactive decay of tritium using a special form of scintillating optical fiber directly in contact with the water to be measured. The system consists of the immersible sensor module containing the optical fiber, and an electronics package, connected by an umbilical cable. The system can be permanently installed for routine water monitoring in wells or process or effluent lines, or can be moved from one location to another for survey use. The electronics will read out tritium activity directly in units of pico Curies per liter, with straightforward calibration. In Phase 1 of the project, we characterized the sensitivity of fluor-doped plastic optical fiber to tritium beta radiation. In addition, we characterized the performance of photomultiplier tubes needed for the system. In parallel with this work, we defined the functional requirements, target specifications, and system configuration for an in situ tritium beta detector that would use the fluor-doped fibers as primary sensors of tritium concentration in water. The major conclusions from the characterization work are: A polystyrene optical fiber with fluor dopant concentration of 2% gave best performance. This fiber had the highest dopant concentration of any fibers tested. Stability may be a problem. The fibers exposed to a 22-day soak in 120 F water experienced a 10x reduction in sensitivity. It is not known whether this was due to the build up of a deposit (a potentially reversible effect) or an irreversible process such as leaching of the scintillating dye. Based on the results achieved, it is premature to initiate Phase 2 and commit to a prototype

  11. Experimental Measurement of In Situ Stress

    NASA Astrophysics Data System (ADS)

    Tibbo, Maria; Milkereit, Bernd; Nasseri, Farzine; Schmitt, Douglas; Young, Paul

    2016-04-01

    The World Stress Map data is determined by stress indicators including earthquake focal mechanisms, in situ measurement in mining, oil and gas boreholes as well as the borehole cores, and geologic data. Unfortunately, these measurements are not only infrequent but sometimes infeasible, and do not provide nearly enough data points with high accuracy to correctly infer stress fields in deep mines around the world. Improvements in stress measurements of Earth's crust is fundamental to several industries such as oil and gas, mining, nuclear waste management, and enhanced geothermal systems. Quantifying the state of stress and the geophysical properties of different rock types is a major complication in geophysical monitoring of deep mines. Most stress measurement techniques involve either the boreholes or their cores, however these measurements usually only give stress along one axis, not the complete stress tensor. The goal of this project is to investigate a new method of acquiring a complete stress tensor of the in situ stress in the Earth's crust. This project is part of a comprehensive, exploration geophysical study in a deep, highly stressed mine located in Sudbury, Ontario, Canada, and focuses on two boreholes located in this mine. These boreholes are approximately 400 m long with NQ diameters and are located at depths of about 1300 - 1600 m and 1700 - 2000 m. Two borehole logging surveys were performed on both boreholes, October 2013 and July 2015, in order to perform a time-lapse analysis of the geophysical changes in the mine. These multi-parameter surveys include caliper, full waveform sonic, televiewer, chargeability (IP), and resistivity. Laboratory experiments have been performed on borehole core samples of varying geologies from each borehole. These experiments have measured the geophysical properties including elastic modulus, bulk modulus, P- and S-wave velocities, and density. The apparatus' used for this project are geophysical imaging cells capable

  12. Autonomous In-Situ Resources Prospector

    NASA Technical Reports Server (NTRS)

    Dissly, R. W.; Buehler, M. G.; Schaap, M. G.; Nicks, D.; Taylor, G. J.; Castano, R.; Suarez, D.

    2004-01-01

    This presentation will describe the concept of an autonomous, intelligent, rover-based rapid surveying system to identify and map several key lunar resources to optimize their ISRU (In Situ Resource Utilization) extraction potential. Prior to an extraction phase for any target resource, ground-based surveys are needed to provide confirmation of remote observation, to quantify and map their 3-D distribution, and to locate optimal extraction sites (e.g. ore bodies) with precision to maximize their economic benefit. The system will search for and quantify optimal minerals for oxygen production feedstock, water ice, and high glass-content regolith that can be used for building materials. These are targeted because of their utility and because they are, or are likely to be, variable in quantity over spatial scales accessible to a rover (i.e., few km). Oxygen has benefits for life support systems and as an oxidizer for propellants. Water is a key resource for sustainable exploration, with utility for life support, propellants, and other industrial processes. High glass-content regolith has utility as a feedstock for building materials as it readily sinters upon heating into a cohesive matrix more readily than other regolith materials or crystalline basalts. Lunar glasses are also a potential feedstock for oxygen production, as many are rich in iron and titanium oxides that are optimal for oxygen extraction. To accomplish this task, a system of sensors and decision-making algorithms for an autonomous prospecting rover is described. One set of sensors will be located in the wheel tread of the robotic search vehicle providing contact sensor data on regolith composition. Another set of instruments will be housed on the platform of the rover, including VIS-NIR imagers and spectrometers, both for far-field context and near-field characterization of the regolith in the immediate vicinity of the rover. Also included in the sensor suite are a neutron spectrometer, ground

  13. Autonomous In-Situ Resources Prospector

    NASA Technical Reports Server (NTRS)

    Dissly, R. W.; Buehler, M. G.; Schaap, M. G.; Nicks, D.; Taylor, G. J.; Castano, R.; Suarez, D.

    2004-01-01

    This presentation will describe the concept of an autonomous, intelligent, rover-based rapid surveying system to identify and map several key lunar resources to optimize their ISRU (In Situ Resource Utilization) extraction potential. Prior to an extraction phase for any target resource, ground-based surveys are needed to provide confirmation of remote observation, to quantify and map their 3-D distribution, and to locate optimal extraction sites (e.g. ore bodies) with precision to maximize their economic benefit. The system will search for and quantify optimal minerals for oxygen production feedstock, water ice, and high glass-content regolith that can be used for building materials. These are targeted because of their utility and because they are, or are likely to be, variable in quantity over spatial scales accessible to a rover (i.e., few km). Oxygen has benefits for life support systems and as an oxidizer for propellants. Water is a key resource for sustainable exploration, with utility for life support, propellants, and other industrial processes. High glass-content regolith has utility as a feedstock for building materials as it readily sinters upon heating into a cohesive matrix more readily than other regolith materials or crystalline basalts. Lunar glasses are also a potential feedstock for oxygen production, as many are rich in iron and titanium oxides that are optimal for oxygen extraction. To accomplish this task, a system of sensors and decision-making algorithms for an autonomous prospecting rover is described. One set of sensors will be located in the wheel tread of the robotic search vehicle providing contact sensor data on regolith composition. Another set of instruments will be housed on the platform of the rover, including VIS-NIR imagers and spectrometers, both for far-field context and near-field characterization of the regolith in the immediate vicinity of the rover. Also included in the sensor suite are a neutron spectrometer, ground

  14. In-situ characterization of gas hydrates

    NASA Astrophysics Data System (ADS)

    Moerz, T.; Brueckmann, W.; Linke, P.; Tuerkay, M.

    2003-04-01

    Gas hydrates are a dynamic reservoir in the marine carbon cycle and a periodically large and focussed source of methane probably constituting the largest carbon reservoir on earth. Therefore an important issue in gas hydrate research is the need for better tools to remotely estimate the volume and stability conditions of marine gas hydrate in the near sub-surface. It is also crucial to precisely determine the hydrate stability conditions in the near sub-surface, where gas hydrates are most susceptible to dissolution under changing P/T conditions. Our knowledge about the occurrence, spatial distribution, and life-cycle of gas hydrates in marine sediments is mainly derived from indirect geophysical and geochemical evidence. In a few instances gas hydrates have also been directly observed and sampled at the sea floor. For regional or global estimates of hydrate volumes and stability conditions however, new techniques for ground-truthing and calibration of geophysical, biological and geochemical methods are needed. During the OTEGA cruise with RV SONNE to Hydrate Ridge off Oregon a new device for in-situ characterization of gas hydrates was deployed and tested for the first time. The tool, HDSD (Hydrate Detection and Stability Determination) is being developed as part of Cooperative Research Center (SFB) 574 "Volatiles and Fluids in Subduction Zones". It is designed to identify and quantify small volumes of near-surface gas hydrate through continuous in-situ thermal and resistivity monitoring in a defined volume of sediment while it is slowly heated to destabilize gas hydrates embedded in it. In its current configuration HDSD is delivered to the seafloor by a video-guided GEOMAR BC Lander system. The sediment volume to be tested for the presence and abundance of gas hydrates is first isolated by a rectangular experiment chamber that is pushed into the upper 30cm of sediment. A "stinger", centrally mounted in the chamber and equipped with two arrays of sensors, provides

  15. In situ monitoring of liquid phase electroepitaxial growth

    NASA Technical Reports Server (NTRS)

    Okamoto, A.; Isozumi, S.; Lagowski, J.; Gatos, H. C.

    1982-01-01

    In situ monitoring of the layer thickness during liquid phase electroepitaxy (LPEE) was achieved with a submicron resolution through precise resistance measurements. The new approach to the study and control of LPEE was applied to growth of undoped and Ge-doped GaAs layers. The in situ determined growth kinetics was found to be in excellent agreement with theory.

  16. Development of the integrated in situ Lasagna process

    SciTech Connect

    Ho, S.; Athmer, C.; Sheridan, P.

    1995-12-31

    Contamination in deep, low permeability soils poses a significant technical challenge to in-situ remediation efforts. Poor accessibility to the contaminants and difficulty in uniform delivery of treatment reagents have rendered existing in-situ methods such as bioremediation, vapor extraction, and pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites.

  17. In-situ soil carbon analysis using inelastic neutron scattering

    USDA-ARS?s Scientific Manuscript database

    In situ soil carbon analysis using inelastic neutron scattering (INS) is based on the emission of 4.43 MeV gamma rays from carbon nuclei excited by fast neutrons. This in-situ method has excellent potential for easily measuring soil carbon since it does not require soil core sampling and processing ...

  18. ABIOTIC IN SITU TECHNOLOGIES FOR GROUNDWATER REMEDIATION CONFERENCE: PROCEEDINGS

    EPA Science Inventory

    The USEPA conference on Abiotic In Situ Technologies for Groundwater Remediation was held in Dallas, TX, 8/31-9/2/99. The goal of the meeting was to disseminate current information on abiotic in situ groundwater treatment echnologies. Although much information is being provided a...

  19. Successful Treatment of Lower Eyelid Melanoma in Situ

    PubMed Central

    Yuan, Joyce; Koh, Justin; Miller, Timothy A.

    2014-01-01

    Summary: We present a brief literature review of the topical immune-modulating medication Imiquimod. The treatment of periorbital melanoma in situ typically requires surgical resection. Here we discuss a case of lower eyelid melanoma in situ successfully treated non-operatively with Imiquimod. PMID:25289347

  20. ABIOTIC IN SITU TECHNOLOGIES FOR GROUNDWATER REMEDIATION CONFERENCE: PROCEEDINGS

    EPA Science Inventory

    The USEPA conference on Abiotic In Situ Technologies for Groundwater Remediation was held in Dallas, TX, 8/31-9/2/99. The goal of the meeting was to disseminate current information on abiotic in situ groundwater treatment echnologies. Although much information is being provided a...

  1. Some implications of in situ uranium mining technology development

    SciTech Connect

    Cowan, C.E.; Parkhurst, M.A.; Cole, R.J.; Keller, D.; Mellinger, P.J.; Wallace, R.W.

    1980-09-01

    A technology assessment was initiated in March 1979 of the in-situ uranium mining technology. This report explores the impediments to development and deployment of this technology and evaluates the environmental impacts of a generic in-situ facility. The report is divided into the following sections: introduction, technology description, physical environment, institutional and socioeconomic environment, impact assessment, impediments, and conclusions. (DLC)

  2. An overview of in situ waste treatment technologies

    SciTech Connect

    Walker, S.; Hyde, R.A.; Piper, R.B.; Roy, M.W.

    1992-01-01

    In situ technologies are becoming an attractive remedial alternative for eliminating environmental problems. In situ treatments typically reduce risks and costs associated with retrieving, packaging, and storing or disposing-waste and are generally preferred over ex situ treatments. Each in situ technology has specific applications, and, in order to provide the most economical and practical solution to a waste problem, these applications must be understood. This paper presents an overview of thirty different in situ remedial technologies for buried wastes or contaminated soil areas. The objective of this paper is to familiarize those involved in waste remediation activities with available and emerging in situ technologies so that they may consider these options in the remediation of hazardous and/or radioactive waste sites. Several types of in situ technologies are discussed, including biological treatments, containment technologies, physical/chemical treatments, solidification/stabilization technologies, and thermal treatments. Each category of in situ technology is briefly examined in this paper. Specific treatments belonging to these categories are also reviewed. Much of the information on in situ treatment technologies in this paper was obtained directly from vendors and universities and this information has not been verified.

  3. An overview of in situ waste treatment technologies

    SciTech Connect

    Walker, S.; Hyde, R.A.; Piper, R.B.; Roy, M.W.

    1992-08-01

    In situ technologies are becoming an attractive remedial alternative for eliminating environmental problems. In situ treatments typically reduce risks and costs associated with retrieving, packaging, and storing or disposing-waste and are generally preferred over ex situ treatments. Each in situ technology has specific applications, and, in order to provide the most economical and practical solution to a waste problem, these applications must be understood. This paper presents an overview of thirty different in situ remedial technologies for buried wastes or contaminated soil areas. The objective of this paper is to familiarize those involved in waste remediation activities with available and emerging in situ technologies so that they may consider these options in the remediation of hazardous and/or radioactive waste sites. Several types of in situ technologies are discussed, including biological treatments, containment technologies, physical/chemical treatments, solidification/stabilization technologies, and thermal treatments. Each category of in situ technology is briefly examined in this paper. Specific treatments belonging to these categories are also reviewed. Much of the information on in situ treatment technologies in this paper was obtained directly from vendors and universities and this information has not been verified.

  4. In-Situ Resource Utilization (ISRU) Capability Roadmap Progress Review

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Duke, Michael

    2005-01-01

    A progress review on In-Situ Resource Utilization (ISRU) capability is presented. The topics include: 1) In-Situ Resource Utilization (ISRU) Capability Roadmap: Level 1; 2) ISRU Emphasized Architecture Overview; 3) ISRU Capability Elements: Level 2 and below; and 4) ISRU Capability Roadmap Wrap-up.

  5. In Situ Burning of Oil Spills

    PubMed Central

    Evans, David D.; Mulholland, George W.; Baum, Howard R.; Walton, William D.; McGrattan, Kevin B.

    2001-01-01

    For more than a decade NIST conducted research to understand, measure and predict the important features of burning oil on water. Results of that research have been included in nationally recognized guidelines for approval of intentional burning. NIST measurements and predictions have played a major role in establishing in situ burning as a primary oil spill response method. Data are given for pool fire burning rates, smoke yield, smoke particulate size distribution, smoke aging, and polycyclic aromatic hydrocarbon content of the smoke for crude and fuel oil fires with effective diameters up to 17.2 m. New user-friendly software, ALOFT, was developed to quantify the large-scale features and trajectory of wind blown smoke plumes in the atmosphere and estimate the ground level smoke particulate concentrations. Predictions using the model were tested successfully against data from large-scale tests. ALOFT software is being used by oil spill response teams to help assess the potential impact of intentional burning. PMID:27500022

  6. In-situ Rb-Sr geochronology

    NASA Astrophysics Data System (ADS)

    Anderson, F. S.; Nowicki, K.; Whitaker, T.

    This paper reports on the first rubidium-strontium (Rb-Sr) radiometric dates using a Laser Desorption Resonance Ionization Mass Spectrometry (LDRIMS) instrument capable of being miniaturized for flight to another planet. The LDRIMS instrument produces dates in under 24 hours, requires minimal sample preparation, and avoids the interference and mass resolution issues associated with other geochronology measurements. We have begun testing the bench-top prototype on the Boulder Creek Granite (BCG), from Colorado, comprised primarily of a gneissic quartz monzonite and granodiorite; whole rock Rb-Sr TIMS measurements result in dates of 1700± 40 Ma [1]. Data reduction of the LDRIMS Rb-Sr measurements on calibrated repeat runs result in a date for the BCG of 1.727± 0.087 Ga (n=288, MSWD=1). Most geochronology applications are willing to accept an MSWD up to ~2.7; at MSWD=2, the precision improves to ± 0.062 Ga. This technology is moving from lab prototype to field deployable instrument, and provides an opportunity to directly address the science goals of Mars Sample Return (MSR) within the bounds posed by current scientific, fiscal, and political pressures on the Mars program. Additionally, LDRIMS could potentially be flown to the Moon under the Discovery or New Frontiers program. We posit that in-situ geochronology missions to Mars to triage and validate samples for Mars Sample Return (MSR) are technically feasible in the 2018-2022 time frame.

  7. Oxidative stress inhibits calpain activity in situ.

    PubMed

    Guttmann, R P; Johnson, G V

    1998-05-22

    In this study, the effects of oxidative stress on calpain-mediated proteolysis and calpain I autolysis in situ were examined. Calpain activity was stimulated in SH-SY5Y human neuroblastoma cells with the calcium ionophore, ionomycin. Calpain-mediated proteolysis of the membrane-permeable fluorescent substrate N-succinyl-L-leucyl-L-leucyl-L-valyl-L-tyrosine-7-amido-4-methylcouma rin, as well as the endogenous protein substrates microtubule-associated protein 2, tau and spectrin, was measured. Oxidative stress, induced by addition of either doxorubicin or 2-mercaptopyridine N-oxide, resulted in a significant decrease in the extent of ionophore-stimulated calpain activity of both the fluorescent compound and the endogenous substrates compared with control, normoxic conditions. Addition of glutathione ethyl ester, as well as other antioxidants, resulted in the retention/recovery of calpain activity, indicating that oxidation-induced calpain inactivation was preventable/reversible. The rate of autolytic conversion of the large subunit of calpain I from 80 to 78 to 76 kDa was decreased during oxidative stress; however, the extent of calpain autolysis was not altered. These data indicate that oxidative stress may reversibly inactivate calpain I in vivo.

  8. DEVELOPMENT OF A PASSIVE, IN SITU, INTEGRATIVE ...

    EPA Pesticide Factsheets

    Until recently, hydrophobic, bioconcentratable compounds have been the primary focus of most environmental organic contaminant investigations, There is an increasing realization that a holistic hazard assessment of complex environmental contaminant mixtures requires data on the concentrations of hydrophilic organic contaminants as well. This group of compounds includes a wide variety of chemicals, including potentially endocrine disrupting and estrogenic contaminants which have been shown to contribute to numerous abnormalities such as impaired reproduction in aquatic organisms exposed in environmental waters. To address this issue, we developed a passive, in situ, sampling device (the Polar Organic Chemical Integrative Sampler or POCIS) which integratively concentrates trace levels of complex mixtures of hydrophilic environmental contaminants, enables the determination of their time-weighted average water concentrations and provides a screening assessment of the toxicological significance of the complex mixture of waterborne contaminants. Using a prototype sampler (effective membrane sampling surface area = 18.2 cm 2) linear uptake of selected herbicides and pharmaceuticals was observed for up to 56 days. Estimation of the ambient water concentrations of chemicals of interest is achieved by using appropriate uptake models and determination of POCIS chemical sampling rates. The research focused on in the subtasks is the development and application of state-of

  9. In situ vitrification: Process and products

    SciTech Connect

    Kindle, C.; Koegler, S.

    1991-06-01

    In situ vitrification (ISV) is an electrically powered thermal treatment process that converts soil into a chemically inert and stable glass and crystalline product. It is similar in concept to bringing a simplified glass manufacturing process to a site and operating it in the ground, using the soil as a glass feed stock. Gaseous emissions are contained, scrubbed, and filtered. When the process is completed, the molten volume cools producing a block of glass and crystalline material that resembles natural obsidian commingled with crystalline phases. The product passes US Environmental Protection Agency (EPA) leach resistance tests, and it can be classified as nonhazardous from a chemical hazard perspective. ISV was developed by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) for application to contaminated soils. It is also being adapted for applications to buried waste, underground tanks, and liquid seepage sites. ISV's then-year development period has included tests on many different site conditions. As of January 1991 there have been 74 tests using PNL's ISV equipment; these tests have ranged from technology development tests using nonhazardous conditions to hazardous and radioactive tests. 2 refs., 6 figs., 7 tabs.

  10. IN-SITU MINING OF PHOSPHATE ORES

    SciTech Connect

    H. El-Shall; R. Stana; A. El-Midany; S. Malekzadah

    2004-12-17

    Presently the mining of Florida phosphate requires the movement of over a 100-ton of materials (overburden, sand, clay) for every ton of phosphate concentrate recovered. Not only is this energy intensive, but it also causes significant stress on the environment. In 2003, the Department of Energy solicited ideas for innovative mining ideas that could significantly improve the efficiency of mining. An award was made to the University of Florida Engineering Research Center to evaluate the in situ mining of phosphates using an aqueous CO{sub 2} solution. Tests were carried out in a 15.2 cm (6-inch) diameter column, 1.83 meter (6 feet) long at pressures up to 117.2 kg/cm{sup 2} (40 psi). Results to date demonstrate that initially the MgO is leached from the ore and then the phosphate. While the tests are continuing, so far they have not demonstrated P{sub 2}O{sub 5} concentrations that are economically attractive.

  11. In situ characterisation of non linear capacitors

    NASA Astrophysics Data System (ADS)

    Laudebat, L.; Bley, V.; Lebey, T.; Schneider, H.; Tounsi, P.

    2001-05-01

    Multilayers ceramic capacitors (MLCC) presenting non linear behaviours of their C(V) characteristics may have interesting applications in power electronics. Most of them have already been described. Nevertheless, the choice of a particular type instead of another one is all the more so difficult since, on one hand the physical mechanisms able to explain this behaviour is far from being understood. On the other hand, C(V) characteristics are in general obtained for low voltage values different from the ones they are going to be involved in. In this paper, direct in situ characterisations of different BaTiO3 based capacitors commercially available are achieved. The role of the capacitors' type (X7R,Z5U), of the temperature and of the voltage waveform (and more particularly its polarity) is demonstrated. Temperature values up to 200 oC are measured during normal operations in a RCD dissipative snubber without any alterations of the C(V) characteristics. All these results are discussed as regards the main physical properties of the constitutive materials in order to reach an optimisation of their use through an appropriate dimensioning.

  12. Photonic MEMS for NIR in-situ

    SciTech Connect

    Bond, T C; Cole, G D; Goddard, L L; Behymer, E

    2007-07-03

    We report on a novel sensing technique combining photonics and microelectromechanical systems (MEMS) for the detection and monitoring of gas emissions for critical environmental, medical, and industrial applications. We discuss how MEMS-tunable vertical-cavity surface-emitting lasers (VCSELs) can be exploited for in-situ detection and NIR spectroscopy of several gases, such as O{sub 2}, N{sub 2}O, CO{sub x}, CH{sub 4}, HF, HCl, etc., with estimated sensitivities between 0.1 and 20 ppm on footprints {approx}10{sup -3} mm{sup 3}. The VCSELs can be electrostatically tuned with a continuous wavelength shift up to 20 nm, allowing for unambiguous NIR signature determination. Selective concentration analysis in heterogeneous gas compositions is enabled, thus paving the way to an integrated optical platform for multiplexed gas identification by bandgap and device engineering. We will discuss here, in particular, our efforts on the development of a 760 nm AlGaAs based tunable VCSEL for O{sub 2} detection.

  13. Calling all hosts: Bacterial communication in situ.

    PubMed

    Cleary, Jessica L; Condren, Alanna R; Zink, Katherine E; Sanchez, Laura M

    2017-03-09

    Bacteria are cosmopolitan organisms that in recent years have demonstrated many roles in maintaining host equilibrium. In this review, we discuss three roles bacteria can occupy in a host: pathogenic, symbiotic, and transient, with a specific focus on how bacterial small molecules contribute to homeostasis or dysbiosis. First, we will dissect how small molecules produced by pathogenic bacteria can be used as a source for communication during colonization and as protection against host immune responses. The ability to achieve a higher level of organization through small molecule communication gives pathogenic bacteria an opportunity for increased virulence and fitness. Conversely, in symbiotic relationships with hosts, small molecules are used in the initial acquisition, colonization, and maintenance of this beneficial population. Chemical signals can come from both the host and symbiont, and it is often observed that these interKingdom symbioses result in coevolution of both species involved. Furthermore, the transition from transient to commensal or opportunistic likely relies on molecular mechanisms. The small molecules utilized and produced by transient bacteria are desirable for both the immune and nutritional benefits they provide to the host. Finally, the advantages and disadvantages of modern analytical techniques that are available to researchers in order to study small molecules in situ is an important aspect of this review. It is our opinion that small molecules produced by bacteria are central to many biological processes and a larger focus on uncovering the function and identity of these small molecules is required to gain a deeper understanding of host-microbe associations.

  14. In situ oil shale retort system

    SciTech Connect

    Hutchins, N.M.; Kvapil, R.; Ricketts, T.E.; Studebaker, I.G.

    1984-04-10

    In situ oil shale retorts are formed in spaced apart rows, with adjacent rows of such retorts being separated by load-bearing barrier pillars of unfragmented formation sufficiently strong for preventing substantial subsidence at the ground surface. Each retort contains a fragmented permeable mass of formation particles containing oil shale. Separate air level drifts are excavated on an upper level of the retorts within alternating barrier pillars, and separate production level drifts are excavated at a lower production level of the retorts within intervening barrier pillars between the barrier pillars having the air level drifts. Each air level drift extends between a pair of adjacent rows of retorts adjacent upper edges of the retorts in the adjacent rows, and each production level drift extends between a pair of adjacent rows of retorts adjacent lower edges of the retorts on sides of the retorts opposite the air level drifts. During retorting operations, air is introduced along the upper edge of each retort through lateral air inlet passages extending from the adjacent air level drift. Off gas and liquid products are withdrawn from each retort through one or more lateral production level passages extending from the lower edge of the retort to the adjacent production level drift. Withdrawal of off gas along the lower edge of each retort opposite the upper edge where air is introduced causes a generally diagonal flow pattern of combustion gas through the fragmented mass from one upper edge toward the opposite lower edge of the retort.

  15. Method for in situ shale oil recovery

    SciTech Connect

    McKee, J.M.; Horton, R.L.

    1986-03-25

    A method is described of in situ processing of oil shale in a subterranean formation. The method consists of: rubblizing a section of oil shale in the subterranean formation, wherein the section has boundaries which form a retort chamber having a top end and a bottom end; removing the rubblized shale from the retort chamber; crushing the rubblized shale so as to produce shale particles of various sizes within a certain overall size range; separating the shale particles according to size into a plurality of shale particle groups, wherein each group includes shale particles within a predetermined group size range, and wherein each group size range makes up a portion of the overall size range; sequentially reloading substantially all of the shale particle groups into the retort chamber so that the shale particle groups are graded according to particle size within the chamber, wherein the largest shale particles are at the bottom end of the retort chamber and the smallest shale particles are at the top end of the retort chamber, the particles being evenly distributed throughout the retort chamber during reloading; retorting the reloaded shale particles such that liquid hydrocarbon products are produced; removing the liquid hydrocarbon products from the retort chamber.

  16. In Situ Immobilization of Selenium in Sediment

    SciTech Connect

    Moore, Robert C.; Stewart, Thomas Austin

    2014-09-01

    This project focused on the use of a sorbent, carbonated apatite, to immobilize selenium in the environment. It is know that apatite will sorb selenium and based on the mechanism of sorption it is theorized that carbonated apatite will be more effective that pure apatite. Immobilization of selenium in the environment is through the use of a sorbent in a permeable reactive barrier (PRB). A PRB can be constructed by trenching and backfill with the sorbent or in the case of apatite as the sorbent formed in situ using the apatite forming solution of Moore (2003, 2004). There is very little data on selenium sorption by carbonated apatite in the literature. Therefore, in this work, the basic sorptive properties of carbonated apatite were investigated. Carbonated apatite was synthesized by a precipitation method and characterized. Batch selenium kinetic and equilibrium experiments were performed. The results indicate the carbonated apatite contained 9.4% carbonate and uptake of selenium as selenite was rapid; 5 hours for complete uptake of selenium vs. more than 100 hours for pure hydroxyapatite reported in the literature. Additionally, the carbonated apatite exhibited significantly higher distribution coefficients in equilibrium experiments than pure apatite under similar experimental conditions. The next phase of this work will be to seek additional funds to continue the research with the goal of eventually demonstrating the technology in a field application.

  17. Assessment of a biological in situ remediation

    SciTech Connect

    Wuerdemann, H.; Lund, N.C.; Gudehus, G.

    1995-12-31

    A field experiment using a bioventing technique has been conducted at the center of contamination at a former gasworks site for 3 years. The emphasis of this investigation is to determine the efficiency of in situ remediation. Due to an extremely heterogeneous distribution of contamination it was impossible to satisfactorily quantify the reduction of hydrocarbons. However, a comparison of highly contaminated soil samples shows a qualitative alteration. The analyses of pollutant composition reveal a significant decrease of low condensed PAHs up to anthracene. The relative increase of high condensed PAHs in the contaminant composition indicates a PAH degradation of 54%. Soil respiration is used to assess the course of remediation. Continuous monitoring of O{sub 2} and CO{sub 2} in the used air leads to an amount of about 2,400 kg of decomposed organics. Large-scale elution tests show a reduction of the sum parameters for the organic pollution of the flushing water of 80%. The PAHs have dropped about 97%. The Microtox test indicates a detoxification of 98%.

  18. Enhancing in situ bioremediation with pneumatic fracturing

    SciTech Connect

    Anderson, D.B.; Peyton, B.M.; Liskowitz, J.L.; Fitzgerald, C.; Schuring, J.R.

    1994-04-01

    A major technical obstacle affecting the application of in situ bioremediation is the effective distribution of nutrients to the subsurface media. Pneumatic fracturing can increase the permeability of subsurface formations through the injection of high pressure air to create horizontal fracture planes, thus enhancing macro-scale mass-transfer processes. Pneumatic fracturing technology was demonstrated at two field sites at Tinker Air Force Base, Oklahoma City, Oklahoma. Tests were performed to increase the permeability for more effective bioventing, and evaluated the potential to increase permeability and recovery of free product in low permeability soils consisting of fine grain silts, clays, and sedimentary rock. Pneumatic fracturing significantly improved formation permeability by enhancing secondary permeability and by promoting removal of excess soil moisture from the unsaturated zone. Postfracture airflows were 500% to 1,700% higher than prefracture airflows for specific fractured intervals in the formation. This corresponds to an average prefracturing permeability of 0.017 Darcy, increasing to an average of 0.32 Darcy after fracturing. Pneumatic fracturing also increased free-product recovery rates of number 2 fuel from an average of 587 L (155 gal) per month before fracturing to 1,647 L (435 gal) per month after fracturing.

  19. In situ bioremediation of chlorinated solvents

    SciTech Connect

    Sack, W.A.; Carriere, P.E.; Whiteman, C.S.; Davis, M.P.; Raman, S.; Cuddeback, J.E.; Shiemke, A.K.

    1995-12-31

    In situ bioremediation of chlorinated organic is receiving growing support and widespread testing in the field. It is an attractive alternative with the potential to destroy contaminants almost completely. The research seeks to exploit the natural symbiotic relationship between methanogenic and methanotrophic microorganisms. The methanogens are able to carry out anaerobic reductive dehalogenation of highly chlorinated solvents while producing methane. The methanotrophs in turn utilize the end products of the methanogens, including the methane, to aerobically degrade the residual CAH compounds to environmentally acceptable end products. Both groups of organisms degrade the CAH compounds cometabolically and require a primary substrate. The purpose of the research is to evaluate and optimize the ability of methanotrophic, methanogenic, and other selected bacteria for cost-effective biotransformation of TCE and other volatile organic compounds (VOCs). This paper describes initial studies using separate anaerobic and aerobic columns. As soon as the initial column studies are complete, the anaerobic and aerobic columns will be combined in both sequential and simultaneous modes to evaluate complete CAH destruction.

  20. Modern laser in situ keratomileusis outcomes.

    PubMed

    Sandoval, Helga P; Donnenfeld, Eric D; Kohnen, Thomas; Lindstrom, Richard L; Potvin, Richard; Tremblay, David M; Solomon, Kerry D

    2016-08-01

    Laser in situ keratomileusis (LASIK) articles published between 2008 and 2015 that contain clinical outcomes data were reviewed and graded for quality, impression, and potential bias. All 97 relevant articles (representing 67 893 eyes) provided a positive or neutral impression of LASIK. Industry bias was not evident. The aggregate loss of 2 or more lines of corrected distance visual acuity was 0.61% (359/58 653). The overall percentage of eyes with uncorrected distance visual acuity better than 20/40 was 99.5% (59 503/59 825). The spherical equivalent refraction was within ±1.0 diopter (D) of the target refraction in 98.6% (59 476/60 329) of eyes, with 90.9% (59 954/65 974) within ±0.5 D. In studies reporting patient satisfaction, 1.2% (129/9726) of patients were dissatisfied with LASIK. Aggregate outcomes appear better than those reported in summaries of the safety and effectiveness of earlier laser refractive surgery systems approved by the U.S. Food and Drug Administration. Modern results support the safety, efficacy, and patient satisfaction of the procedure. Proprietary or commercial disclosures are listed after the references. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. Aluminum-Based Cast In Situ Composites: A Review

    NASA Astrophysics Data System (ADS)

    Pramod, S. L.; Bakshi, Srinivasa R.; Murty, B. S.

    2015-06-01

    In situ composites are a class of composite materials in which the reinforcement is formed within the matrix by reaction during the processing. In situ method of composite synthesis has been widely followed by researchers because of several advantages over conventional stir casting such as fine particle size, clean interface, and good wettability of the reinforcement with the matrix and homogeneous distribution of the reinforcement compared to other processes. Besides this, in situ processing of composites by casting route is also economical and amenable for large scale production as compared to other methods such as powder metallurgy and spray forming. Commonly used reinforcements for Al and its alloys which can be produced in situ are Al2O3, AlN, TiB2, TiC, ZrB2, and Mg2Si. The aim of this paper is to review the current research and development in aluminum-based in situ composites by casting route.

  2. In situ containment and stabilization of buried waste

    SciTech Connect

    Allan, M.L.; Kukacka, L.E.; Heiser, J.H.

    1992-11-01

    The objective of the project was to develop, demonstrate and implement advanced grouting materials for the in-situ installation of impermeable, durable subsurface barriers and caps around waste sites and for the in-situ stabilization of contaminated soils. Specifically, the work was aimed at remediation of the Chemical Waste (CWL) and Mixed Waste Landfills (MWL) at Sandia National Laboratories (SNL) as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). This report documents this project, which was conducted in two subtasks. These were (1) Capping and Barrier Grouts, and (2) In-situ Stabilization of Contaminated Soils. Subtask 1 examined materials and placement methods for in-situ containment of contaminated sites by subsurface barriers and surface caps. In Subtask 2 materials and techniques were evaluated for in-situ chemical stabilization of chromium in soil.

  3. MENDING THE IN SITU MANIPULATION BARRIER

    SciTech Connect

    PETERSEN, S.W.

    2006-02-06

    In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the In Situ Redox Manipulation (ISRM) technology, was installed a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. The reduction of Fe(III) to ferrous [Fe(II)] iron provides the primary reduction capacity to reduce Cr(VI) to the +3 state, which is less mobile and less toxic. Bench-scale and field-scale treatability tests were initially conducted to demonstrate proof-of principle and to provide data for estimation of barrier longevity. These calculations estimated barrier longevity in excess of twenty years. However, several years after initial and secondary treatment, groundwater in a number of wells has been found to contain elevated chromium (Cr) concentrations, indicating

  4. in situ Calcite Precipitation for Contaminant Immobilization

    SciTech Connect

    Yoshiko Fujita; Robert W. Smith

    2009-08-01

    in situ Calcite Precipitation for Contaminant Immobilization Yoshiko Fujita (Yoshiko.fujita@inl.gov) (Idaho National Laboratory, Idaho Falls, Idaho, USA) Robert W. Smith (University of Idaho-Idaho Falls, Idaho Falls, Idaho, USA) Subsurface radionuclide and trace metal contaminants throughout the U.S. Department of Energy (DOE) complex pose one of DOE’s greatest challenges for long-term stewardship. One promising stabilization mechanism for divalent trace ions, such as the short-lived radionuclide strontium-90, is co-precipitation in calcite. Calcite, a common mineral in the arid western U.S., can form solid solutions with trace metals. The rate of trace metal incorporation is susceptible to manipulation using either abiotic or biotic means. We have previously demonstrated that increasing the calcite precipitation rate by stimulating the activity of urea hydrolyzing microorganisms can result in significantly enhanced Sr uptake. Urea hydrolysis causes the acceleration of calcium carbonate precipitation (and trace metal co-precipitation) by increasing pH and alkalinity, and also by liberating the reactive cations from the aquifer matrix via exchange reactions involving the ammonium ion derived from urea: H2NCONH2 + 3H2O ? 2NH4+ + HCO3- + OH- urea hydrolysis >X:2Ca + 2NH4+ ? 2>X:NH4 + Ca2+ ion exchange Ca2+ + HCO3- + OH- ? CaCO3(s) + H2O calcite precipitation where >X: is a cation exchange site on the aquifer matrix. This contaminant immobilization approach has several attractive features. Urea hydrolysis is catalyzed by the urease enzyme, which is produced by many indigenous subsurface microorganisms. Addition of foreign microbes is unnecessary. In turn the involvement of the native microbes and the consequent in situ generation of reactive components in the aqueous phase (e.g., carbonate and Ca or Sr) can allow dissemination of the reaction over a larger volume and/or farther away from an amendment injection point, as compared to direct addition of the reactants at

  5. In Situ Probe Science at Saturn

    NASA Astrophysics Data System (ADS)

    Atkinson, David H.; Lunine, Jonathan I.; Simon-Miller, Amy A.; Atreya, Sushil K.; Brinckerhoff, William B.; Colaprete, Anthony; Coustenis, Athena; Fletcher, Leigh N.; Guillot, Tristan; Lebreton, Jean-Pierre; Mahaffy, Paul; Mousis, Olivier; Orton, Glenn S.; Reh, Kim; Spilker, Linda J.; Spilker, Thomas R.; Webster, Chris R.

    2014-05-01

    A fundamental goal of solar system exploration is to understand the origin of the solar system, the initial stages, conditions, and processes by which the solar system formed, how the formation process was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres. Several theories have been put forward to explain the process of solar system formation, and the origin and evolution of the giant planets and their atmospheres. Each theory offers quantifiable predictions of the abundances of noble gases He, Ne, Ar, Kr, and Xe, and abundances of key isotopic ratios 4He/3He, D/H, 15N/14N, 18O/16O, and 13C/12C. Detection of certain disequilibrium species, diagnostic of deeper internal processes and dynamics of the atmosphere, would also help discriminate between competing theories. Many of the key atmospheric constituents needed to discriminate between alternative theories of giant planet formation and chemical evolution are either spectrally inactive or primarily located in the deeper atmosphere inaccessible to remote sensing from Earth, flyby, or orbiting spacecraft. Abundance measurements of these key constituents, including the two major molecular carriers of carbon, methane and carbon monoxide (neither of which condense in Saturn's atmosphere), sulfur which is expected to be well-mixed below the 4 to 5-bar ammonium hydrosulfide (NH4SH) cloud, and gradients of nitrogen below the NH4SH cloud and oxygen in the upper layers of the H2O and H2O-NH4 solution cloud, must be made in situ and can only be achieved by an entry probe descending through 10 bars. Measurements of the critical abundance profiles of these key constituents into the deeper well-mixed atmosphere must be complemented by measurements of the profiles of atmospheric structure and dynamics at high vertical

  6. LONG TERM IN SITU DISPOSAL ENGINEERING STUDY

    SciTech Connect

    ADAMS; CARLSON; BROCKMAN

    2003-07-23

    Patent application pulled per Ken Norris (FH General Counsel). The objective of this study is to devise methods, produce conceptual designs, examine and select alternatives, and estimate costs for the demonstration of long-term (300-year) in situ disposal of an existing waste disposal site. The demonstration site selected is the 216-A-24 Crib near the 200 East Area. The site contains a fission product inventory and has experienced plant, animal, and inadvertent than intrusion. Of the potential intrusive events and transport pathways at the site, potential human intrusion has been given primary consideration in barrier design. Intrusion by wind, plants, and animals has been given secondary consideration. Groundwater modeling for a number of barrier configurations has been carried out to help select a barrier that will minimize water infiltration and waste/water contact time. The estimated effective lifetime and cost of 20 barrier schemes, using a variety of materials, have been evaluated. The schemes studied include single component surface barriers, multicomponent barriers, and massively injected grout barriers. Five barriers with high estimated effective lifetimes and relatively low costs have been selected for detailed evaluation. They are basalt riprap barriers, massive soil barriers, salt basin barriers, multi-component fine/coarse barriers, and cemented basalt barriers. A variety of materials and configurations for marking the site have also been considered. A decision analysis was completed to select a barrier scheme for demonstration. The analysis indicated that the basalt riprap alternative would be the preferred choice for a full-scale demonstration. The recommended approach is to demonstrate the basalt riprap barrier at the 216-A-24 Crib as soon as possible. Methods and costs of assessing effectiveness of the demonstration are also described. Preliminary design modifications and costs for applying the five selected barrier schemes to other site types are

  7. In-Situ Wire Damage Detection System

    NASA Technical Reports Server (NTRS)

    Williams, Martha; Roberson, Luke; Tate, Lanetra; Smith, Trent; Gibson, Tracy; Medelius, Pedro; Jolley, Scott

    2012-01-01

    An In-Situ Wire Damage Detection System (ISWDDS) has been developed that is capable of detecting damage to a wire insulation, or a wire conductor, or to both. The system will allow for realtime, continuous monitoring of wiring health/integrity and reduce the number of false negatives and false positives while being smaller, lighter in weight, and more robust than current systems. The technology allows for improved safety and significant reduction in maintenance hours for aircraft, space vehicles, satellites, and other critical high-performance wiring systems for industries such as energy production and mining. The integrated ISWDDS is comprised of two main components: (1) a wire with an innermost core conductor, an inner insulation film, a conductive layer or inherently conductive polymer (ICP) covering the inner insulation film, an outermost insulation jacket; and (2) smart connectors and electronics capable of producing and detecting electronic signals, and a central processing unit (CPU) for data collection and analysis. The wire is constructed by applying the inner insulation films to the conductor, followed by the outer insulation jacket. The conductive layer or ICP is on the outer surface of the inner insulation film. One or more wires are connected to the CPU using the smart connectors, and up to 64 wires can be monitored in real-time. The ISWDDS uses time domain reflectometry for damage detection. A fast-risetime pulse is injected into either the core conductor or conductive layer and referenced against the other conductor, producing transmission line behavior. If either conductor is damaged, then the signal is reflected. By knowing the speed of propagation of the pulse, and the time it takes to reflect, one can calculate the distance to and location of the damage.

  8. In situ Probe Science at Saturn

    NASA Astrophysics Data System (ADS)

    Atkinson, D. H.; Mousis, O.; Lunine, J. I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.; Mahaffy, P.; Orton, G. S.; Reh, K.; Spilker, L. J.; Spilker, T. R.; Webster, C.

    2014-04-01

    A fundamental goal of solar system exploration is to understand the origin of the solar system, the initial stages, conditions, and processes by which the solar system formed, how the formation process was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres. Several theories have been put forward to explain the process of solar system formation, and the origin and evolution of the giant planets and their atmospheres. Each theory offers quantifiable predictions of the abundances of noble gases He, Ne, Ar, Kr, and Xe, and abundances of key isotopic ratios 4He/3He, D/H, 15N/14N, 18O/16O, and 13C/12C. Detection of certain disequilibrium species, diagnostic of deeper internal processes and dynamics of the atmosphere, would also help discriminate between competing theories. Measurements of the critical abundance profiles of these key constituents into the deeper well-mixed atmosphere must be complemented by measurements of the profiles of atmospheric structure and dynamics at high vertical resolution and also require in situ exploration. The atmospheres of the giant planets can also serve as laboratories to better understand the atmospheric chemistries, dynamics, processes, and climates on all planets including Earth, and offer a context and provide a ground truth for exoplanets and exoplanetary systems. Additionally, Giant planets have long been thought to play a critical role in the development of potentially habitable planetary systems. In the context of giant planet science provided by the Galileo, Juno, and Cassini missions to Jupiter and Saturn, a small, relatively shallow Saturn probe capable of measuring abundances and isotopic ratios of key atmospheric constituents, and atmospheric structure including pressures, temperatures, dynamics, and cloud locations

  9. Cost performance assessment of in situ vitrification

    SciTech Connect

    Showalter, W.E.; Letellier, B.C.; Booth, S.R.; Barnes-Smith, P.

    1992-09-01

    In situ vitrification (ISV) is a thermal treatment technology with promise for the destruction or immobilization of hazardous materials in contaminated soils. It has developed over the past decade to a level of maturity where meaningful cost effectiveness studies may be performed. The ISV process melts 4 to 25 m{sup 2} of undisturbed soil to a maximum depth of 6 m into an obsidian-like glass waste form by applying electric current (3750 kill) between symmetrically spaced electrodes. Temperatures of approximately 2000{degree}C drive off and destroy complex organics which are captured in an off-gas treatment system, while radio-nuclides are incorporated into the homogeneous glass monolith. A comparative life-cycle cost evaluation between mobile rotary kiln incineration and ISV was performed to quantitatively identify appropriate performance regimes and components of cost which are sensitive to the implementation of each technology. Predictions of melt times and power consumption were obtained from an ISV performance model over ranges of several parameters including electrode spacing, soil moisture, melt depth, electrical resistivity, and soil density. These data were coupled with manpower requirements, capitalization costs, and a melt placement optimization routine to allow interpolation over a wide variety of site characteristics. For the purpose of this study, a single site scenario representative of a mixed waste evaporation pond was constructed. Preliminary comparisons between ISV and incineration show that while operating costs are comparable, ISV avoids secondary treatment and monitored storage of radioactive waste that would be required following conventional incineration. It is the long term storage of incinerated material that is the most expensive component.

  10. Cost performance assessment of in situ vitrification

    SciTech Connect

    Showalter, W.E.; Letellier, B.C.; Booth, S.R. ); Barnes-Smith, P. )

    1992-01-01

    In situ vitrification (ISV) is a thermal treatment technology with promise for the destruction or immobilization of hazardous materials in contaminated soils. It has developed over the past decade to a level of maturity where meaningful cost effectiveness studies may be performed. The ISV process melts 4 to 25 m{sup 2} of undisturbed soil to a maximum depth of 6 m into an obsidian-like glass waste form by applying electric current (3750 kill) between symmetrically spaced electrodes. Temperatures of approximately 2000{degree}C drive off and destroy complex organics which are captured in an off-gas treatment system, while radio-nuclides are incorporated into the homogeneous glass monolith. A comparative life-cycle cost evaluation between mobile rotary kiln incineration and ISV was performed to quantitatively identify appropriate performance regimes and components of cost which are sensitive to the implementation of each technology. Predictions of melt times and power consumption were obtained from an ISV performance model over ranges of several parameters including electrode spacing, soil moisture, melt depth, electrical resistivity, and soil density. These data were coupled with manpower requirements, capitalization costs, and a melt placement optimization routine to allow interpolation over a wide variety of site characteristics. For the purpose of this study, a single site scenario representative of a mixed waste evaporation pond was constructed. Preliminary comparisons between ISV and incineration show that while operating costs are comparable, ISV avoids secondary treatment and monitored storage of radioactive waste that would be required following conventional incineration. It is the long term storage of incinerated material that is the most expensive component.

  11. In-situ bioassays using caged bivalves

    SciTech Connect

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    It is important to make the distinction between chemical measurements to assess bioaccumulation potential versus biological measurements to assess potential bioeffects because bioaccumulation is not a bioeffect. Caging provides a unique opportunity to make synoptic measurements of each and facilitates making these measurements over space and time. Measuring bioaccumulation in resident and transplanted bivalves has probably been the most frequently used form of an in-situ bioassay because bivalves concentrate chemicals in their tissues. They are also easy to collect, cage, and measure. The authors have refined bivalve bioassay methods by minimizing the size range of test animals, making repetitive measurements of the same individuals, and standardizing test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Growth measurements can serve two purposes in this assessment strategy: (1) An integrated biological response endpoint that is easily quantifiable and with significance to the population, and (2) A means of calibrating bioaccumulation by assessing the relative health and physiological state of tissues that have accumulated the chemicals. In general, the authors have found the highest bioconcentration factors associated with the highest growth rates, the highest concentrations ({micro}g/g) of chemicals in juvenile mussels, and the highest chemical content ({micro}g/animal) in adult mussels. Without accounting for possible dilution of chemical concentrations by tissue growth or magnification through degrowth, contaminant concentrations can be misleading. Examples are provided for the Sudbury River in Massachusetts (Elliptio complanata), San Diego Bay (Mytilus galloprovincialis), and the Harbor Island Superfund Site in Puget Sound (Mytilus trossulus).

  12. Cyclotorsion during laser in situ keratomileusis.

    PubMed

    Chang, John

    2008-10-01

    To determine the magnitude of cyclotorsion during excimer laser ablation using a dynamic iris eye tracker. Guy Hugh Chan Refractive Surgery Centre, Department of Ophthalmology, Hong Kong Sanatorium and Hospital, Hong Kong, China. This retrospective study comprised 245 eyes (137 patients) that had laser in situ keratomileusis (LASIK) for myopia with or without astigmatism by the same surgeon. The magnitude of cyclotorsion during LASIK was recorded as the maximum, average, and minimum positions according to the angle of deviation displayed on the excimer laser computer screen. Measurements of cyclotorsion were performed during laser ablation. The mean total cyclotorsion was 2.181 degrees+/-1.392 (SD) (range 0.0 to 13.3 degrees). The mean average position (AP) was +0.134+/-1.851 degrees (range -7.0 degrees [excyclotorsion] to +12.6 degrees [incyclotorsion]). Forty-five eyes (18.4%) had an AP greater than +/-2 degrees, and 168 eyes (68.6%) deviated from the zero position at the onset of laser ablation. The mean incyclotorsion was 2.136+/-1.440 degrees (78 eyes, 31.8%) and the mean excyclotorsion, 1.772+/-0.809 degrees (78 eyes, 31.8%). Eighty-six eyes (35.1%) had cyclotorsion in both directions (mixed cyclotorsion). The mean cyclotorsion was 2.670+/-1.588 degrees. Eight (3.3%) of the 109 patients having simultaneous bilateral LASIK had bilateral incyclotorsion or bilateral excyclotorsion. Cyclotorsion occurs before and during laser ablation. An active rotational eye tracker is fundamental to compensate for cyclotorsion and to enable greater precision in excimer laser ablation delivery.

  13. In situ oil shale retorting: water quality

    SciTech Connect

    Tompkins, M.A.

    1981-03-10

    Rio Blanco Oil Shale Company completed the first burn on their modified in-situ system located in the Piceance Basin of Colorado. Gas stream analyses were performed using a small computerized mass spectrometer. These analyses were made continuously from a sample line originating at the off-gas knockout drum. In addition, the feasibility of determining trace sulfur gases in this mixture was tested. The mass spectrometer has a detection limit of about 5 ppM for a typical trace component in air or other simple gas matrix. However, because of the complex organic matrix composing the oil shale gas, it becomes very difficult to positively identify most trace components at this low ppM level. The sulfur gases which have the fewest interferences include H/sub 2/S, COS, CH/sub 3/SH and SO/sub 2/. These gases can be determined at approximatey the 15 to 25 ppM level. Mass spectrometric analysis of low- or sub-ppM level trace components in complex gas mixture would require pre-treatment of the gas such as concentration or separation to be effective. Positive identifications were made on H/sub 2/S, CH/sub 3/SH, COS and SO/sub 2/. Water samples were taken from five points in the Rio Blanco MIS process for organic characterization and toxicity screening. There was considerable variation in the toxicity of the retort waters relative to both time into the burn and the location of the sampling point. The scrubber water samples were more toxic than the other samples. This is most likely due to the higher pH of these samples. The east holding pond samples were not toxic. These samples represent an integrated sample set as all process waters are finally discharged into this holding pond.

  14. US appearance of ductal carcinoma in situ.

    PubMed

    Wang, Lilian C; Sullivan, Megan; Du, Hongyan; Feldman, Marina I; Mendelson, Ellen B

    2013-01-01

    Ductal carcinoma in situ (DCIS) is a noninvasive cancer that accounts for 25% of all breast cancers diagnosed in the United States. DCIS is a heterogeneous disease process with varied clinical manifestations and a broad spectrum of imaging findings. With advances in technology, the ability to detect early-stage cancers has improved, and understanding the role of ultrasonography (US) in the multimodality era of detection and diagnosis is paramount. When calcifications are identified at mammography, US can be performed to evaluate for an invasive component and to allow possible US-guided biopsy. Use of high-frequency transducers, spectral compounding, and speckle reduction algorithms can aid in the detection of calcifications. Calcified DCIS most commonly manifests as echogenic foci located within a mass or duct, associated with internal microlobulations, or distributed in a branch pattern. Noncalcified DCIS, which is more often identified in symptomatic patients, may manifest as a hypoechoic mass with microlobulated margins and no posterior acoustic features, or it may have a "pseudomicrocystic" appearance. Harmonic imaging and coronal reconstruction may improve detection of noncalcified DCIS. The appearance of DCIS at "second-look" US can be subtle and may warrant a lower threshold for detection, given a higher pretest probability of malignancy. US features are nonspecific, and careful correlation with respect to lesion location, size, shape, and depth is needed. The presence of internal vascularity can help increase the positive predictive value of US in this setting. US is a useful adjunct to mammography and magnetic resonance imaging, and recognizing the US appearance of DCIS will aid in the detection and diagnosis of this disease entity.

  15. Microbial Repopulation Following In Situ STAR Remediation

    NASA Astrophysics Data System (ADS)

    Gerhard, J.; Overbeeke, G.; Edwards, E.; Lomheim, L.; Grant, G.

    2016-12-01

    STAR (Self-sustaining Treatment for Active Remediation) is an emerging remediation technology that employs a self-sustaining smouldering reaction to destroy nonaqueous phase liquids (NAPLs) in the subsurface. The reaction front travels outwards from an ignition well at approximately 0.5 per day and subjects the soil to temperatures of 400°C-1000°C. The objectives of this work were to monitor re-saturation of the soil over time and quantify the microbial repopulation of the treated zone. STAR is currently being applied as a full scale, in situ remedy for coal tar beneath a former creosol manufacturing facility in New Jersey, USA. This study analyzed soil cores taken at regular intervals following STAR treatment, allowing time for groundwater to re-infiltrate and for microbial populations to potentially reestablish. Soil and groundwater were analyzed for total number of microorganisms via quantitative Polymerase Chain Reaction (qPCR), as well as microbial diversity via amplicon sequencing. Results demonstrate that microbes rapidly repopulated over a 2 month period to 106 gene copies/g of soil. However, concentrations in the treated zone did not rise above this concentration over 6 months post-STAR, indicating a low carrying capacity of the treated soil. To examine the system in more detail and consider the effects of bio-stimulation, a bench top column study using site soil and artificial groundwater explored the rate at which STAR-treated soil is repopulated with naturally occurring microorganisms in the presence and absence of lactate and a terminal electron acceptor. Results demonstrated that biostimulation did not increase the carrying capacity of the STAR treated sol, but rather shifted the microbial community to reflect the TEA provided, in this case, promoting sulfate reducers. Overall, the work illustrates that microbial populations in STAR treated soil do recover via groundwater infiltration but robust communities will take time to naturally establish.

  16. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    PubMed Central

    Noble, Stephen R.

    2015-01-01

    Abstract Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (r e). In situ COT, LWP, and r e were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and r e 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14–36%. MODIS in situ r e correlations were strong, but MODIS 2.1 µm r e exceeded in situ r e, which contributed to LWP bias; in POST, MODIS r e was 20–30% greater than in situ r e. Maximum in situ r e near cloud top showed comparisons nearer 1:1. Other MODIS r e bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS r e bias that propagates to LWP while still capturing variability. PMID:27708990

  17. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    NASA Astrophysics Data System (ADS)

    Noble, Stephen R.; Hudson, James G.

    2015-08-01

    Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (re). In situ COT, LWP, and re were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and re 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14-36%. MODIS in situ re correlations were strong, but MODIS 2.1 µm re exceeded in situ re, which contributed to LWP bias; in POST, MODIS re was 20-30% greater than in situ re. Maximum in situ re near cloud top showed comparisons nearer 1:1. Other MODIS re bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS re bias that propagates to LWP while still capturing variability.

  18. NOVEL IN-SITU METAL AND MINERAL EXTRACTION TECHNOLOGY

    SciTech Connect

    Glenn O'Gorman; Hans von Michaelis; Gregory J. Olson

    2004-09-22

    This white paper summarizes the state of art of in-situ leaching of metals and minerals, and describes a new technology concept employing improved fragmentation of ores underground in order to prepare the ore for more efficient in-situ leaching, combined with technology to continuously improve solution flow patterns through the ore during the leaching process. The process parameters and economic benefits of combining the new concept with chemical and biological leaching are described. A summary is provided of the next steps required to demonstrate the technology with the goal of enabling more widespread use of in-situ leaching.

  19. Evaluation of In Situ Combustion for Schrader Bluff

    SciTech Connect

    Sarathi, P.; Strycker, A.; Wang, S.

    1999-03-11

    The focus of this report is on the results related to evaluation of in situ combustion processes applied to Schrader Bluff. Initially, overall screening processes were applied to determine which of the EOR methods, were most appropriate for Schrader Bluff. In situ combustion was among the methods considered potentially favorable and was evaluated further. Laboratory scale tube runs were conducted to determine if the kinetic parameters for the crude oil were favorable. Additional sensitivity studies were conducted to evaluate the recovery potential. Described in this report are the results of the (1) initial screening,(2) experimental tube runs, and (3) simulation sensitivity studies as related to in situ combustion in Schrader Bluff.

  20. In Situ Probe Science at Saturn

    NASA Technical Reports Server (NTRS)

    Atkinson, D.H.; Lunine, J.I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.; hide

    2014-01-01

    A fundamental goal of solar system exploration is to understand the origin of the solar sys-tem, the initial stages, conditions, and processes by which the solar system formed, how the formation pro-cess was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres. Several theories have been put forward to explain the process of solar system formation, and the origin and evolution of the giant planets and their atmospheres. Each theory offers quantifiable predictions of the abundances of noble gases He, Ne, Ar, Kr, and Xe, and abundances of key isotopic ratios 4He3He, DH, 15N14N, 18O16O, and 13C12C. Detection of certain dis-equilibrium species, diagnostic of deeper internal pro-cesses and dynamics of the atmosphere, would also help discriminate between competing theories. Measurements of the critical abundance profiles of these key constituents into the deeper well-mixed at-mosphere must be complemented by measurements of the profiles of atmospheric structure and dynamics at high vertical resolution and also require in situ explora-tion. The atmospheres of the giant planets can also serve as laboratories to better understand the atmospheric chem-istries, dynamics, processes, and climates on all planets including Earth, and offer a context and provide a ground truth for exoplanets and exoplanetary systems. Additionally, Giant planets have long been thought to play a critical role in the development of potentially habitable planetary systems. In the context of giant planet science provided by the Galileo, Juno, and Cassini missions to Jupiter and Sat-urn, a small, relatively shallow Saturn probe capable of measuring abundances and isotopic ratios of key at-mospheric constituents, and atmospheric structure in-cluding pressures, temperatures, dynamics, and cloud

  1. In Situ Measurements of Meteoric Ions

    NASA Technical Reports Server (NTRS)

    Grebowsky, Joseph M.; Aiken, Arthur C.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Extraterrestrial material is the source of metal ions in the Earth's atmosphere, Each year approx. 10(exp 8) kg of material is intercepted by the Earth. The origin of this material is predominantly solar orbiting interplanetary debris from comets or asteroids that crosses the Earth's orbit. It contains a very small amount of interstellar material. On occasion the Earth passes through enhanced amounts of debris associated with the orbit of a decaying comet. This leads to enhanced meteor shower displays for up to several days. The number flux of shower material is typically several times the average sporadic background influx of material. Meteoric material is some of the earliest material formed in the solar system. By studying the relative elemental abundances of atmospheric metal ions, information can be gained on the chemical composition of cometary debris and the chemical makeup of the early solar system. Using in situ sampling with rocket-borne ion mass spectrometers; there have been approximately 50 flights that made measurements of the metal ion abundances at attitudes between 80 and 130 km. It is this altitude range where incoming meteoric particles am ablated, the larger ones giving rise to visible meteor. displays. In several rocket measurements isotopic ratios of different atomic ion mass components and metal molecular ion concentrations have been determined and used to identify unambiguously the measured species and to investigate the processes controlling the metal ion distributions The composition of the Earth's ionosphere was first sampled by an ion mass spectrometer flown an a rocket in 1956. In 1958 a rocket-borne ion spectrometer identified, fbr the first time, a layer of metal ions near 95 km. These data were interpreted as evidence of an extraterrestrial rather than a terrestrial source. Istomin predicted: "It seems probable that with some improvement in the method that analysis of the ion composition in the E-region may be used for determining

  2. Miniature LIMS System for In Situ Detection of Biosignatures

    NASA Astrophysics Data System (ADS)

    Riedo, A.; Tulej, M.; Neuland, M. B.; Wurz, P.

    2016-05-01

    The current measurement capabilities of our miniature Laser Ablation Ionization Mass Spectrometer for sensitive and quantitative in situ chemical analyses (element, isotope and molecular) of solids on planetary surfaces will be presented.

  3. Epoxy nanodielectrics fabricated with in situ and ex situ techniques

    SciTech Connect

    Tuncer, Enis; Polyzos, Georgios; Sauers, Isidor; James, David Randy; Ellis, Alvin R; More, Karren Leslie

    2012-01-01

    In this study, we report fabrication and characterisation of a nanocomposite system composed of a commercial resin and extremely small (several nanometres in diameter) titanium dioxide particles. Nanoparticles were synthesised in situ with particle nucleation occurring inside the resin matrix. In this nanodielectric fabrication method, the nanoparticle precursor was mixed to the resin solution, and the nanoparticles were in situ precipitated. Note that no high shear mixing equipment was needed to improve particle dispersion - nanoparticles were distributed in the polymer matrix uniformly since particle nucleation occurs uniformly throughout the matrix. The properties of in situ nanodielectrics are compared to the unfilled resin and an ex situ nanocomposite. We anticipate that the presented in situ nanocomposite would be employed in high-temperature superconductivity applications. In additions, the improvement shown in the dielectric breakdown indicates that conventional high-voltage components and systems can be reduced in size with novel nanodielectrics.

  4. In situ quantification of genomic instability in breast cancer progression

    SciTech Connect

    Ortiz de Solorzano, Carlos; Chin, Koei; Gray, Joe W.; Lockett, Stephen J.

    2003-05-15

    Genomic instability is a hallmark of breast and other solid cancers. Presumably caused by critical telomere reduction, GI is responsible for providing the genetic diversity required in the multi-step progression of the disease. We have used multicolor fluorescence in situ hybridization and 3D image analysis to quantify genomic instability cell-by-cell in thick, intact tissue sections of normal breast epithelium, preneoplastic lesions (usual ductal hyperplasia), ductal carcinona is situ or invasive carcinoma of the breast. Our in situ-cell by cell-analysis of genomic instability shows an important increase of genomic instability in the transition from hyperplasia to in situ carcinoma, followed by a reduction of instability in invasive carcinoma. This pattern suggests that the transition from hyperplasia to in situ carcinoma corresponds to telomere crisis and invasive carcinoma is a consequence of telomerase reactivation afertelomere crisis.

  5. Recent Developments for In Situ Treatment of Metal Contaminated Soils

    EPA Pesticide Factsheets

    This report assists the remedy selection process by providing information on four in situ technologies for treating soil contaminated with metals. The four approaches are electrokinetic remediation, phytoremediation, soil flushing, and...

  6. ISHMAEL: In-Situ Sample Handling Modular Analytical Experimental Laboratory

    NASA Technical Reports Server (NTRS)

    Bearman, G. H.; Kossakovski, D. A.

    2000-01-01

    In-Situ instruments are an integral part of mission designs for exploration of planetary surfaces. A technology gap exists today between sample acquisition and sample analysis tools. Integrated science payload packages need an integrated sample handling system.

  7. In situ transesterification of highly wet microalgae using hydrochloric acid.

    PubMed

    Kim, Bora; Im, Hanjin; Lee, Jae W

    2015-06-01

    This study addresses in situ transesterification of highly wet microalgae with hydrochloric acid (HCl) as a catalyst. In situ transesterification was performed by heating the mixture of wet algal cells, HCl, methanol, and solvent in one pot, resulting in the fatty acid methyl ester (FAME) yield over 90% at 95°C. The effects of reaction variables of temperature, amounts of catalyst, reactant, and solvent, and type of solvents on the yield were investigated. Compared with the catalytic effect of H2SO4, in situ transesterification using HCl has benefits of being less affected by moisture levels that are as high as or above 80%, and requiring less amounts of catalyst and solvent. For an equimolar amount of catalyst, HCl showed 15wt.% higher FAME yield than H2SO4. This in situ transesterification using HCl as a catalyst would help to realize a feasible way to produce biodiesel from wet microalgae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. In-situ polymerization PLOT columns I: divinylbenzene

    NASA Technical Reports Server (NTRS)

    Shen, T. C.

    1992-01-01

    A novel method for preparation of porous-layer open-tubular (PLOT) columns is described. The method involves a simple and reproducible, straight-forward in-situ polymerization of monomer directly on the metal tube.

  9. Anchoring Technology for In Situ Exploration of Small Bodie

    NASA Technical Reports Server (NTRS)

    Steltzner, A.; Nasif, A.

    2000-01-01

    Comets, asteroids and other small bodies found in the solar system do not possess enough gravity to ensure spacecraft contact forces sufficient to allow many types of in situ science, such as core or surface sampling.

  10. SITE TECHNOLOGY CAPSULE: GEOSAFE CORPORATION IN SITU VITRIFICATION TECHNOLOGY

    EPA Science Inventory

    The Geosafe In Situ Vitrification (ISV) Technology is designed to treat soils, sludges, sediments, and mine tallings contaminated with organic, inorganic, and radioactive compounds. The organic compounds are pyrolyzed and reduced to simple gases which are collected under a treatm...

  11. GEOSAFE CORPORATION IN SITU VITRIFICATION: INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    This report summarizes the findings associated with a Demonstration of the Geosafe Corporation (Geosafe) In Situ Vitrification (ISV) Process. The Geosafe ISV Technology was evaluated under the EPA Superfund Innovative Technology Evaluation (SITE) Program in conjuction with remedi...

  12. Volatile Extractor (PVEx) for Planetary In Situ Resource Utilization

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Morrison, P.; Vendiola, V.; Paz, A.

    2017-02-01

    Here we present a trade study and final approach for efficient extraction of volatiles from planetary regolith for the purpose of In Situ Resource Utilization. The project is SBIR funded and hardware is being fabricated.

  13. Emerging technology of in situ cell free expression protein microarrays.

    PubMed

    Nand, Amita; Gautam, Anju; Pérez, Javier Batista; Merino, Alejandro; Zhu, Jinsong

    2012-02-01

    Recently, in situ protein microarrays have been developed for large scale analysis and high throughput studies of proteins. In situ protein microarrays produce proteins directly on the solid surface from pre-arrayed DNA or RNA. The advances in in situ protein microarrays are exemplified by the ease of cDNA cloning and cell free protein expression. These technologies can evaluate, validate and monitor protein in a cost effective manner and address the issue of a high quality protein supply to use in the array. Here we review the importance of recently employed methods: PISA (protein in situ array), DAPA (DNA array to protein array), NAPPA (nucleic acid programmable protein array) and TUSTER microarrays and the role of these methods in proteomics.

  14. GEOSAFE CORPORATION IN SITU VITRIFICATION: INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    This report summarizes the findings associated with a Demonstration of the Geosafe Corporation (Geosafe) In Situ Vitrification (ISV) Process. The Geosafe ISV Technology was evaluated under the EPA Superfund Innovative Technology Evaluation (SITE) Program in conjuction with remedi...

  15. In-situ polymerization PLOT columns I: divinylbenzene.

    PubMed

    Shen, T C

    1992-06-01

    A novel method for preparation of porous-layer open-tubular (PLOT) columns is described. The method involves a simple and reproducible, straight-forward in-situ polymerization of monomer directly on the metal tube.

  16. Advanced hydraulic fracturing methods to create in situ reactive barriers

    SciTech Connect

    Murdoch, L. |; Siegrist, B.; Meiggs, T.

    1997-12-31

    This article describes the use of hydraulic fracturing to increase permeability in geologic formations where in-situ remedial action of contaminant plumes will be performed. Several in-situ treatment strategies are discussed including the use of hydraulic fracturing to create in situ redox zones for treatment of organics and inorganics. Hydraulic fracturing methods offer a mechanism for the in-situ treatment of gently dipping layers of reactive compounds. Specialized methods using real-time monitoring and a high-energy jet during fracturing allow the form of the fracture to be influenced, such as creation of assymmetric fractures beneath potential sources (i.e. tanks, pits, buildings) that should not be penetrated by boring. Some examples of field applications of this technique such as creating fractures filled with zero-valent iron to reductively dechlorinate halogenated hydrocarbons, and the use of granular activated carbon to adsorb compounds are discussed.

  17. Real-Time In Situ Landing Site Assessment

    NASA Astrophysics Data System (ADS)

    Adams, D.; Hibbard, K.; McGee, T.

    2017-02-01

    Landing spacecraft on other objects in the solar system provides a unique opportunity to make direct in situ science measurements, but extraterrestrial environments create unique challenges for the design and testing of the system.

  18. In Situ Instrument to Detect Prebiotic Compounds in Planetary Ices

    NASA Technical Reports Server (NTRS)

    Getty, Stephanie A.; Dworkin, Jason; Glavin, Daniel P.; Southard, Adrian; Balvin, Manuel; Kotecki, Carl; Ferrance, Jerome

    2013-01-01

    The development of an in situ LC-MS instrument for future planetary science missions to icy surfaces that are of high astrobiology and astrochemistry potential will advance our understanding of organics in the solar system.

  19. Green Remediation Best Management Practices: Implementing In Situ Thermal Technologies

    EPA Pesticide Factsheets

    Over recent years, the use of in situ thermal technologies such as electrical resistance heating, thermal conductive heating, and steam enhanced extraction to remediate contaminated sites has notably increased.

  20. In-situ resist colloidal lithography for affordable plasmonics

    NASA Astrophysics Data System (ADS)

    Bochenkov, Vladimir E.

    2017-09-01

    A recently developed extension of Sparse Colloidal Lithography, an In-situ Resist Colloidal Lithography method is presented. The technique is based on in-situ deposition of structured resist layer having low adhesion to target material to form nanoparticles of desired shape. A high potential of the method is demonstrated by the examples of fabricated plasmonic nanostructures with different shapes, including concentric and non-concentric rings, disks and chiral comma-like particles.

  1. Superconducting proximity effect for in situ and model layered systems

    SciTech Connect

    Finnemore, D.K.

    1980-01-01

    The primary drawback for in situ composites is that the ac losses are higher than for mechanically produced multifilamentary wire. To develop an understanding of the proximity effect so that analytical expressions will be available for design, a model system is developed based on PbCd. Items discussed include boundary conditions at SN interface, phonon spectral function, supercurrents through normal barriers, flux entry fields, and implications for in situ composites. (GHT)

  2. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    PubMed

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials.

  3. In Situ Resource Utilization (ISRU II) Technical Interchange Meeting

    NASA Technical Reports Server (NTRS)

    Kaplan, David (Compiler); Saunders, Stephen R. (Compiler)

    1997-01-01

    This volume contains extended abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU II) Technical Interchange Meeting, November 18-19, 1997, at the Lunar and Planetary Institute, Houston, Texas. Included are topics which include: Extraterrestrial resources, in situ propellant production, sampling of planetary surfaces, oxygen production, water vapor extraction from the Martian atmosphere, gas generation, cryogenic refrigeration, and propellant transport and storage.

  4. In-Situ Analysis System for Correlated Electron Heterostructures

    DTIC Science & Technology

    2014-11-20

    expandable and compact photo- electron spectroscopy tools for in-situ characterization of complex functional superlattices and ultra-thin films. The...chamber. Initially, the prime set of tools allows for XPS, Auger and EELS spectroscopies. The views, opinions and/or findings contained in this report...highly expandable and compact photo-electron spectroscopy tools for in-situ characterization of complex functional superlattices and ultra-thin

  5. NASA wind shear flight test in situ results

    NASA Technical Reports Server (NTRS)

    Oseguera, Rosa M.

    1992-01-01

    The main objectives in developing the NASA in situ windshear detection algorithm were to provide a measurement standard for validation of forward-look sensors under development, and to demonstrate the algorithm's ability to operate with a suitably low nuisance alert rate. It was necessary to know exactly how the algorithm was implemented and what parameters and filtering were used, in order to be able to fully test its effectiveness and correlate in situ results with forward-look sensor data.

  6. In situ hybridization in the plant Kalanchoë daigremontiana.

    PubMed

    Garcês, Helena; Sinha, Neelima

    2009-10-01

    Here we describe in detail the detection of gene expression in plant tissues of Kalanchoë daigremontiana by in situ hybridization analyses. Included are methods for making RNA transcript probes, probe-tissue hybridization, and detection of antisense RNA probes. The in situ hybridization technique is used to determine which cells or group of cells in particular tissue(s) express a gene of interest.

  7. In situ measurement of conductivity during nanocomposite film deposition

    NASA Astrophysics Data System (ADS)

    Blattmann, Christoph O.; Pratsinis, Sotiris E.

    2016-05-01

    Flexible and electrically conductive nanocomposite films are essential for small, portable and even implantable electronic devices. Typically, such film synthesis and conductivity measurement are carried out sequentially. As a result, optimization of filler loading and size/morphology characteristics with respect to film conductivity is rather tedious and costly. Here, freshly-made Ag nanoparticles (nanosilver) are made by scalable flame aerosol technology and directly deposited onto polymeric (polystyrene and poly(methyl methacrylate)) films during which the resistance of the resulting nanocomposite is measured in situ. The formation and gas-phase growth of such flame-made nanosilver, just before incorporation onto the polymer film, is measured by thermophoretic sampling and microscopy. Monitoring the nanocomposite resistance in situ reveals the onset of conductive network formation by the deposited nanosilver growth and sinternecking. The in situ measurement is much faster and more accurate than conventional ex situ four-point resistance measurements since an electrically percolating network is detected upon its formation by the in situ technique. Nevertheless, general resistance trends with respect to filler loading and host polymer composition are consistent for both in situ and ex situ measurements. The time lag for the onset of a conductive network (i.e., percolation) depends linearly on the glass transition temperature (Tg) of the host polymer. This is attributed to the increased nanoparticle-polymer interaction with decreasing Tg. Proper selection of the host polymer in combination with in situ resistance monitoring therefore enable the optimal preparation of conductive nanocomposite films.

  8. In situ diffusion experiment in granite: phase I.

    PubMed

    Vilks, P; Cramer, J J; Jensen, M; Miller, N H; Miller, H G; Stanchell, F W

    2003-03-01

    A program of in situ experiments, supported by laboratory studies, was initiated to study diffusion in sparsely fractured rock (SFR), with a goal of developing an understanding of diffusion processes within intact crystalline rock. Phase I of the in situ diffusion experiment was started in 1996, with the purpose of developing a methodology for estimating diffusion parameter values. Four in situ diffusion experiments, using a conservative iodide tracer, were performed in highly stressed SFR at a depth of 450 m in the Underground Research Laboratory (URL). The experiments, performed over a 2 year period, yielded rock permeability estimates of 2 x 10(-21) m(2) and effective diffusion coefficients varying from 2.1 x 10(-14) to 1.9 x 10(-13) m(2)/s, which were estimated using the MOTIF code. The in situ diffusion profiles reveal a characteristic "dog leg" pattern, with iodide concentrations decreasing rapidly within a centimeter of the open borehole wall. It is hypothesized that this is an artifact of local stress redistribution and creation of a zone of increased constrictivity close to the borehole wall. A comparison of estimated in situ and laboratory diffusivities and permeabilities provides evidence that the physical properties of rock samples removed from high-stress regimes change. As a result of the lessons learnt during Phase I, a Phase II in situ program has been initiated to improve our general understanding of diffusion in SFR.

  9. IN SITU FIELD TESTING OF PROCESSES

    SciTech Connect

    J.S.Y. YANG

    2004-11-08

    The purpose of this scientific analysis report is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts and surface-based boreholes through unsaturated zone (UZ) tuff rock units. In situ testing, monitoring, and associated laboratory studies are conducted to directly assess and evaluate the waste emplacement environment and the natural barriers to radionuclide transport at Yucca Mountain. This scientific analysis report supports and provides data to UZ flow and transport model reports, which in turn contribute to the Total System Performance Assessment (TSPA) of Yucca Mountain, an important document for the license application (LA). The objectives of ambient field-testing activities are described in Section 1.1. This report is the third revision (REV 03), which supercedes REV 02. The scientific analysis of data for inputs to model calibration and validation as documented in REV 02 were developed in accordance with the Technical Work Plan (TWP) ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (BSC 2004 [DIRS 167969]). This revision was developed in accordance with the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.4) for better integrated, consistent, transparent, traceable, and more complete documentation in this scientific analysis report and associated UZ flow and transport model reports. No additional testing or analyses were performed as part of this revision. The list of relevant acceptance criteria is provided by ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654]), Table 3-1. Additional deviations from the TWP regarding the features, events, and processes (FEPs) list are discussed in Section 1.3. Documentation in this report includes descriptions of how, and under what conditions, the tests were conducted. The descriptions and

  10. Characterizing In Situ Uranium and Groundwater Flux

    NASA Astrophysics Data System (ADS)

    Cho, J.; Newman, M. A.; Stucker, V.; Peacock, A.; Ranville, J.; Cabaniss, S.; Hatfield, K.; Annable, M. D.; Klammler, H.; Perminova, I. V.

    2010-12-01

    The goal of this project is to develop a new sensor that incorporates the field-tested concepts of the passive flux meter to provide direct in situ measures of uranium and groundwater fluxes. The sensor uses two sorbents and resident tracers to measure uranium flux and specific discharge directly; but, sensor principles and design should also apply to fluxes of other radionuclides. Flux measurements will assist with obtaining field-scale quantification of subsurface processes affecting uranium transport (e.g., advection) and transformation (e.g., uranium attenuation) and further advance conceptual and computational models for field scale simulations. Project efforts will expand our current understanding of how field-scale spatial variations in uranium fluxes and those for salient electron donor/acceptors, and groundwater are coupled to spatial variations in measured microbial biomass/community composition, effective field-scale uranium mass balances, attenuation, and stability. The new sensor uses an anion exchange resin to measure uranium fluxes and activated carbon with resident tracers to measure water fluxes. Several anion-exchange resins including Dowex 21K and 21K XLT, Purolite A500, and Lewatit S6328 were tested as sorbents for capturing uranium on the sensor and Lewatit S6328 was determined to be the most effective over the widest pH range. Four branched alcohols proved useful as resident tracers for measuring groundwater flows using activated carbon for both laboratory and field conditions. The flux sensor was redesigned to prevent the discharge of tracers to the environment, and the new design was tested in laboratory box aquifers and the field. Geochemical modeling of equilibrium speciation using Visual Minteq and an up-to-date thermodynamic data base suggested Ca-tricarbonato-uranyl complexes predominate under field conditions, while calculated uranyl ion activities were sensitive to changes in pH, dissolved inorganic carbon (DIC) and alkaline earth

  11. In situ management and domestication of plants in Mesoamerica.

    PubMed

    Casas, Alejandro; Otero-Arnaiz, Adriana; Pérez-Negrón, Edgar; Valiente-Banuet, Alfonso

    2007-11-01

    Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. Artificial selection operating on in situ managed populations of the

  12. In situ Management and Domestication of Plants in Mesoamerica

    PubMed Central

    Casas, Alejandro; Otero-Arnaiz, Adriana; Pérez-Negrón, Edgar; Valiente-Banuet, Alfonso

    2007-01-01

    Background and Aims Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. Methods Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. Key Results Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. Conclusions Artificial

  13. In situ vitrification: application analysis for stabilization of transuranic waste

    SciTech Connect

    Oma, K.H.; Farnsworth, R.K.; Rusin, J.M.

    1982-09-01

    The in situ vitrification process builds upon the electric melter technology previously developed for high-level waste immobilization. In situ vitrification converts buried wastes and contaminated soil to an extremely durable glass and crystalline waste form by melting the materials, in place, using joule heating. Once the waste materials have been solidified, the high integrity waste form should not cause future ground subsidence. Environmental transport of the waste due to water or wind erosion, and plant or animal intrusion, is minimized. Environmental studies are currently being conducted to determine whether additional stabilization is required for certain in-ground transuranic waste sites. An applications analysis has been performed to identify several in situ vitrification process limitations which may exist at transuranic waste sites. Based on the process limit analysis, in situ vitrification is well suited for solidification of most in-ground transuranic wastes. The process is best suited for liquid disposal sites. A site-specific performance analysis, based on safety, health, environmental, and economic assessments, will be required to determine for which sites in situ vitrification is an acceptable disposal technique. Process economics of in situ vitrification compare favorably with other in-situ solidification processes and are an order of magnitude less than the costs for exhumation and disposal in a repository. Leachability of the vitrified product compares closely with that of Pyrex glass and is significantly better than granite, marble, or bottle glass. Total release to the environment from a vitrified waste site is estimated to be less than 10/sup -5/ parts per year. 32 figures, 30 tables.

  14. In situ magnetic separation for extracellular protein production.

    PubMed

    Käppler, Tobias; Cerff, Martin; Ottow, Kim; Hobley, Timothy; Posten, Clemens

    2009-02-01

    A new approach for in situ product removal from bioreactors is presented in which high-gradient magnetic separation is used. This separation process was used for the adsorptive removal of proteases secreted by Bacillus licheniformis. Small, non-porous bacitracin linked magnetic adsorbents were employed directly in the broth during the fermentation, followed by in situ magnetic separation. Proof of the concept was first demonstrated in shake flask culture, then scaled up and applied during a fed batch cultivation in a 3.7 L bioreactor. It could be demonstrated that growth of B. licheniformis was not influenced by the in situ product removal step. Protease production also remained the same after the separation step. Furthermore, degradation of the protease, which followed first order kinetics, was reduced by using the method. Using a theoretical modeling approach, we could show that protease yield in total was enhanced by using in situ magnetic separation. The process described here is a promising technique to improve overall yield in bio production processes which are often limited due to weak downstream operations. Potential limitations encountered during a bioprocess can be overcome such as product inhibition or degradation. We also discuss the key points where research is needed to implement in situ magnetic separation in industrial production.

  15. Feasibility of in situ beta ray measurements in underwater environment.

    PubMed

    Park, Hye Min; Park, Ki Hyun; Kang, Sung Won; Joo, Koan Sik

    2017-09-01

    We describe an attempt at the development of an in situ detector for beta ray measurements in underwater environment. The prototype of the in situ detector is based on a CaF2: Eu scintillator using crystal light guide and Si photomultiplier. Tests were conducted using various reference sources for evaluating the linearity and stability of the detector in underwater environment. The system is simple and stable for long-term monitoring, and consumes low power. We show here an effective detection distance of 7 mm and a 2.273 MeV end-point energy spectrum of (90)Sr/(90)Y when using the system underwater. The results demonstrate the feasibility of in situ beta ray measurements in underwater environment and can be applied for designing an in situ detector for radioactivity measurement in underwater environment. The in situ detector can also have other applications such as installation on the marine monitoring platform and quantitative analysis of radionuclides. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Nanoparticles laden in situ gelling system for ocular drug targeting

    PubMed Central

    Kumar, Divya; Jain, Nidhi; Gulati, Neha; Nagaich, Upendra

    2013-01-01

    Designing an ophthalmic drug delivery system is one of the most difficult challenges for the researchers. The anatomy and physiology of eye create barriers like blinking which leads to the poor retention time and penetration of drug moiety. Some conventional ocular drug delivery systems show shortcomings such as enhanced pre-corneal elimination, high variability in efficiency, and blurred vision. To overcome these problems, several novel drug delivery systems such as liposomes, nanoparticles, hydrogels, and in situ gels have been developed. In situ-forming hydrogels are liquid upon instillation and undergo phase transition in the ocular cul-de-sac to form viscoelastic gel and this provides a response to environmental changes. In the past few years, an impressive number of novel temperature, pH, and ion-induced in situ-forming systems have been reported for sustain ophthalmic drug delivery. Each system has its own advantages and drawbacks. Thus, a combination of two drug delivery systems, i.e., nanoparticles and in situ gel, has been developed which is known as nanoparticle laden in situ gel. This review describes every aspects of this novel formulation, which present the readers an exhaustive detail and might contribute to research and development. PMID:23662277

  17. In-situ pyrogenic production of biodiesel from swine fat.

    PubMed

    Lee, Jechan; Tsang, Yiu Fai; Jung, Jong-Min; Oh, Jeong-Ik; Kim, Hyung-Wook; Kwon, Eilhann E

    2016-11-01

    In-situ production of fatty acid methyl esters from swine fat via thermally induced pseudo-catalytic transesterification on silica was investigated in this study. Instead of methanol, dimethyl carbonate (DMC) was used as acyl acceptor to achieve environmental benefits and economic viability. Thermo-gravimetric analysis of swine fat reveals that swine fat contains 19.57wt.% of water and impurities. Moreover, the fatty acid profiles obtained under various conditions (extracted swine oil+methanol+NaOH, extracted swine oil+DMC+pseudo-catalytic, and swine fat+DMC+pseudo-catalytic) were compared. These profiles were identical, showing that the introduced in-situ transesterification is technically feasible. This also suggests that in-situ pseudo-catalytic transesterification has a high tolerance against impurities. This study also shows that FAME yield via in-situ pseudo-catalytic transesterification of swine fat reached up to 97.2% at 380°C. Therefore, in-situ pseudo-catalytic transesterification can be applicable to biodiesel production of other oil-bearing biomass feedstocks. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. In situ TEM of radiation effects in complex ceramics.

    PubMed

    Lian, Jie; Wang, L M; Sun, Kai; Ewing, Rodney C

    2009-03-01

    In situ transmission electron microscopy (TEM) has been extensively applied to study radiation effects in a wide variety of materials, such as metals, ceramics and semiconductors and is an indispensable tool in obtaining a fundamental understanding of energetic beam-matter interactions, damage events, and materials' behavior under intense radiation environments. In this article, in situ TEM observations of radiation effects in complex ceramics (e.g., oxides, silicates, and phosphates) subjected to energetic ion and electron irradiations have been summarized with a focus on irradiation-induced microstructural evolution, changes in microchemistry, and the formation of nanostructures. New results for in situ TEM observation of radiation effects in pyrochlore, A(2)B(2)O(7), and zircon, ZrSiO(4), subjected to multiple beam irradiations are presented, and the effects of simultaneous irradiations of alpha-decay and beta-decay on the microstructural evolution of potential nuclear waste forms are discussed. Furthermore, in situ TEM results of radiation effects in a sodium borosilicate glass subjected to electron-beam exposure are introduced to highlight the important applications of advanced analytical TEM techniques, including Z-contrast imaging, energy filtered TEM (EFTEM), and electron energy loss spectroscopy (EELS), in studying radiation effects in materials microstructural evolution and microchemical changes. By combining ex situ TEM and advanced analytical TEM techniques with in situ TEM observations under energetic beam irradiations, one can obtain invaluable information on the phase stability and response behaviors of materials under a wide range of irradiation conditions.

  19. In situ measurements of phytoplankton fluorescence using low cost electronics.

    PubMed

    Leeuw, Thomas; Boss, Emmanuel S; Wright, Dana L

    2013-06-19

    Chlorophyll a fluorometry has long been used as a method to study phytoplankton in the ocean. In situ fluorometry is used frequently in oceanography to provide depth-resolved estimates of phytoplankton biomass. However, the high price of commercially manufactured in situ fluorometers has made them unavailable to some individuals and institutions. Presented here is an investigation into building an in situ fluorometer using low cost electronics. The goal was to construct an easily reproducible in situ fluorometer from simple and widely available electronic components. The simplicity and modest cost of the sensor makes it valuable to students and professionals alike. Open source sharing of architecture and software will allow students to reconstruct and customize the sensor on a small budget. Research applications that require numerous in situ fluorometers or expendable fluorometers can also benefit from this study. The sensor costs US$150.00 and can be constructed with little to no previous experience. The sensor uses a blue LED to excite chlorophyll a and measures fluorescence using a silicon photodiode. The sensor is controlled by an Arduino microcontroller that also serves as a data logger.

  20. Nanoparticles laden in situ gelling system for ocular drug targeting.

    PubMed

    Kumar, Divya; Jain, Nidhi; Gulati, Neha; Nagaich, Upendra

    2013-01-01

    Designing an ophthalmic drug delivery system is one of the most difficult challenges for the researchers. The anatomy and physiology of eye create barriers like blinking which leads to the poor retention time and penetration of drug moiety. Some conventional ocular drug delivery systems show shortcomings such as enhanced pre-corneal elimination, high variability in efficiency, and blurred vision. To overcome these problems, several novel drug delivery systems such as liposomes, nanoparticles, hydrogels, and in situ gels have been developed. In situ-forming hydrogels are liquid upon instillation and undergo phase transition in the ocular cul-de-sac to form viscoelastic gel and this provides a response to environmental changes. In the past few years, an impressive number of novel temperature, pH, and ion-induced in situ-forming systems have been reported for sustain ophthalmic drug delivery. Each system has its own advantages and drawbacks. Thus, a combination of two drug delivery systems, i.e., nanoparticles and in situ gel, has been developed which is known as nanoparticle laden in situ gel. This review describes every aspects of this novel formulation, which present the readers an exhaustive detail and might contribute to research and development.

  1. Frontiers of in situ electron microscopy

    SciTech Connect

    Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying

    2015-01-01

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by in this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.

  2. In Situ Treatment of Chromium-Contaminated Groundwater

    SciTech Connect

    Fruchter, Jonathan S. )

    2002-12-01

    In Situ Treatment of Chromate Contaminated Groundwater Jonathan S. Fruchter Pacific Northwest National Laboratory Abstract of paper published in Environmental Science and Technology, 2002 Although not as common as solvent or fuel products contamination, chromate (chromium (VI)) contamination of groundwater is relatively widespread. Chromate has a variety of industrial uses, including chrome plating, steel making, and use as a corrosion inhibitor, wood preservative, well-drilling fluid additive, biocide, and as a pigment in paints and primers. EPA has estimated that as many as 1300 sites in the United States may have groundwater contaminated with chromate. The paper discusses a number of approaches to in situ treatment of chromate contamination in groundwater aquifers. The approaches include various types of chemical treatments, biological treatments and natural attenuation. The strengths and weaknesses of each method are discussed and compared. Field examples of two types of chemical treatment, in situ redox manipulation and chemically enhanced pump and treat are presented. It is concluded that in situ methods show promise, but can be difficult to implement due to site-specific conditions and limited long-term experience with these methods. As more performance and cost data are acquired for the demonstrations that are ongoing, and continuing research increases our understanding of subsurface processes, in situ treatment methods for chromium (VI) contamination in groundwater should gain wider acceptance.

  3. In situ Measurements of Phytoplankton Fluorescence Using Low Cost Electronics

    PubMed Central

    Leeuw, Thomas; Boss, Emmanuel S.; Wright, Dana L.

    2013-01-01

    Chlorophyll a fluorometry has long been used as a method to study phytoplankton in the ocean. In situ fluorometry is used frequently in oceanography to provide depth-resolved estimates of phytoplankton biomass. However, the high price of commercially manufactured in situ fluorometers has made them unavailable to some individuals and institutions. Presented here is an investigation into building an in situ fluorometer using low cost electronics. The goal was to construct an easily reproducible in situ fluorometer from simple and widely available electronic components. The simplicity and modest cost of the sensor makes it valuable to students and professionals alike. Open source sharing of architecture and software will allow students to reconstruct and customize the sensor on a small budget. Research applications that require numerous in situ fluorometers or expendable fluorometers can also benefit from this study. The sensor costs US$150.00 and can be constructed with little to no previous experience. The sensor uses a blue LED to excite chlorophyll a and measures fluorescence using a silicon photodiode. The sensor is controlled by an Arduino microcontroller that also serves as a data logger. PMID:23783738

  4. In Situ Operating Room-Based Simulation: A Review.

    PubMed

    Owei, Lily; Neylan, Christopher J; Rao, Raghavendra; Caskey, Robert C; Morris, Jon B; Sensenig, Richard; Brooks, Ari D; Dempsey, Daniel T; Williams, Noel N; Atkins, Joshua H; Baranov, Dimitry Y; Dumon, Kristoffel R

    To systematically review the literature surrounding operating room-based in situ training in surgery. A systematic review was conducted of MEDLINE. The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, and employed the Population, Intervention, Comparator, Outcome (PICO) structure to define inclusion/exclusion criteria. The Kirkpatrick model was used to further classify the outcome of in situ training when possible. The search returned 308 database hits, and ultimately 19 articles were identified that met the stated PICO inclusion criteria. Operating room-based in situ simulation is used for a variety of purposes and in a variety of settings, and it has the potential to offer unique advantages over other types of simulation. Only one randomized controlled trial was conducted comparing in situ simulation to off-site simulation, which found few significant differences. One large-scale outcome study showed improved perinatal outcomes in obstetrics. Although in situ simulation theoretically offers certain advantages over other types of simulation, especially in addressing system-wide or environmental threats, its efficacy has yet to be clearly demonstrated. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  5. In-situ Data Analysis Framework for ACME Land Simulations

    NASA Astrophysics Data System (ADS)

    Wang, D.; Yao, C.; Jia, Y.; Steed, C.; Atchley, S.

    2015-12-01

    The realistic representation of key biogeophysical and biogeochemical functions is the fundamental of process-based ecosystem models. Investigating the behavior of those ecosystem functions within real-time model simulation can be a very challenging due to the complex of both model and software structure of an environmental model, such as the Accelerated Climate Model for Energy (ACME) Land Model (ALM). In this research, author will describe the urgent needs and challenges for in-situ data analysis for ALM simulations, and layouts our methods/strategies to meet these challenges. Specifically, an in-situ data analysis framework is designed to allow users interactively observe the biogeophyical and biogeochemical process during ALM simulation. There are two key components in this framework, automatically instrumented ecosystem simulation, in-situ data communication and large-scale data exploratory toolkit. This effort is developed by leveraging several active projects, including scientific unit testing platform, common communication interface and extreme-scale data exploratory toolkit. Authors believe that, based on advanced computing technologies, such as compiler-based software system analysis, automatic code instrumentation, and in-memory data transport, this software system provides not only much needed capability for real-time observation and in-situ data analytics for environmental model simulation, but also the potentials for in-situ model behavior adjustment via simulation steering.

  6. Advanced physical models and monitoring methods for in situ bioremediation

    SciTech Connect

    Simon, K.; Chalmer, P.

    1996-05-30

    Numerous reports have indicated that contamination at DOE facilities is widespread and pervasive. Existing technology is often too costly or ineffective in remediating these contamination problems. An effective method to address one class of contamination, petroleum hydrocarbons, is in situ bioremediation. This project was designed to provide tools and approaches for increasing the reliability of in situ bioremediation. An example of the recognition within DOE for developing these tools is in the FY-1995 Technology Development Needs Summary of the Office of Technology Development of the US DOE. This document identifies specific needs addressed by this research. For example, Section 3.3 Need Statement IS-3 identifies the need for a {open_quotes}Rapid method to detect in situ biodegradation products.{close_quotes} Also, BW-I identifies the need to recognize boundaries between clean and contaminated materials and soils. Metabolic activity could identify these boundaries. Measuring rates of in situ microbial activity is critical to the fundamental understanding of subsurface microbiology and in selecting natural attenuation as a remediation option. Given the complexity and heterogeneity of subsurface environments, a significant cost incurred during bioremediation is the characterization of microbial activity, in part because so many intermediate end points (biomass, gene frequency, laboratory measurements of activity, etc.) must be used to infer in situ activity. A fast, accurate, real-time, and cost-effective method is needed to determine success of bioremediation at DOE sites.

  7. Energy from true in situ processing of Antrim oil shale: initial in situ extraction trials

    SciTech Connect

    McNamara, P.H.

    1980-04-01

    This report covers the three in situ extraction trials performed at The Dow Chemical Company's existing oil shale site near Peck, Michigan, from August 11, 1977 to May 24, 1978 and the subsequent analysis. The trials were conducted at a depth of 1200 to 1300 feet for a total operating time of 109 days. Ignition was achieved by an electric heater and by a propane burner using coal and charcoal to increase the input of energy. Gas having an energy value of 50 to 55 Btu/scf was prodcued. The energy recovered in the third and most productive trial compared to the energy used for ignition reached a ratio of 4.8. A cyclic operation, called Huff and Puff, gave a 47 to 65% improvement in energy recovery compared to a single forward combustion. No sulfur compounds were detected in the production gas. Particulate measurement was not of value in monitoring the burning process. The trials reported, and the information gathered for them, provide a basis for a trial at a new site adjacent to the existing site.

  8. 30 CFR 933.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... CAROLINA § 933.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  9. 30 CFR 912.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... § 912.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  10. 30 CFR 933.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... CAROLINA § 933.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  11. 30 CFR 922.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... § 922.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  12. 30 CFR 910.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... § 910.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  13. 30 CFR 922.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... § 922.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  14. 30 CFR 939.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... ISLAND § 939.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  15. 30 CFR 912.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... § 912.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  16. 30 CFR 941.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... DAKOTA § 941.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  17. 30 CFR 947.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... § 947.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  18. 30 CFR 941.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... DAKOTA § 941.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  19. 30 CFR 939.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... ISLAND § 939.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  20. 30 CFR 921.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Special performance standards-in situ... MASSACHUSETTS § 921.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  1. 30 CFR 910.828 - Special performance standards-in situ processing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special performance standards-in situ... § 910.828 Special performance standards—in situ processing. Part 828 of this chapter, Special Permanent Program Performance Standards—In Situ Processing, shall apply to any person who conducts in situ...

  2. System for enhanced longevity of in situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  3. Method for enhanced longevity of in situ microbial filter used for bioremediation

    DOEpatents

    Carman, M. Leslie; Taylor, Robert T.

    1999-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  4. In Situ Atom Probe Deintercalation of Lithium-Manganese-Oxide.

    PubMed

    Pfeiffer, Björn; Maier, Johannes; Arlt, Jonas; Nowak, Carsten

    2017-01-30

    Atom probe tomography is routinely used for the characterization of materials microstructures, usually assuming that the microstructure is unaltered by the analysis. When analyzing ionic conductors, however, gradients in the chemical potential and the electric field penetrating dielectric atom probe specimens can cause significant ionic mobility. Although ionic mobility is undesirable when aiming for materials characterization, it offers a strategy to manipulate materials directly in situ in the atom probe. Here, we present experimental results on the analysis of the ionic conductor lithium-manganese-oxide with different atom probe techniques. We demonstrate that, at a temperature of 30 K, characterization of the materials microstructure is possible without measurable Li mobility. Also, we show that at 298 K the material can be deintercalated, in situ in the atom probe, without changing the manganese-oxide host structure. Combining in situ atom probe deintercalation and subsequent conventional characterization, we demonstrate a new methodological approach to study ionic conductors even in early stages of deintercalation.

  5. Production rates of terrestrial in-situ-produced cosmogenic nuclides

    SciTech Connect

    Reedy, R.C.; Tuniz, C.; Fink, D.

    1993-12-31

    Production rates of cosmogenic nuclides made in situ in terrestrial samples and how they are applied to the interpretation of measured radionuclide concentrations were discussed at a one-day Workshop held 2 October 1993 in Sydney, Australia. The status of terrestrial in-situ studies using the long-lived radionuclides {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, and {sup 41}Ca and of various modeling and related studies were presented. The relative uncertainties in the various factors that go into the interpretation of these terrestrial in-situ cosmogenic nuclides were discussed. The magnitudes of the errors for these factors were estimated and none dominated the final uncertainty.

  6. Changing assessment practice through in situ faculty development.

    PubMed

    Pickworth, G E; Snyman, W D

    2012-02-01

    The aim of this article is to describe the process of an in situ staff development process with the objective to influence change in assessment practice. An in situ training course focusing on writing questions for written examinations, but also including some contextual aspects of assessment practice, was therefore developed and implemented. The anticipated change was measured against Kirkpatrick's four levels for evaluating training programmes. As a whole, the reaction from the participants was positive (Kirkpatrick Level 1), and in a number of instances, learning, which includes changes in attitude, knowledge and skills (Kirkpatrick Level 2) and change in behaviour (Kirkpatrick Level 3), was observed. To conclude, the staff development initiative in the form of in situ assessment training facilitated change resulting in an improvement in assessment practice in the School in a relatively short period of time.

  7. Robot-Assisted Antegrade In-Situ Fenestrated Stent Grafting

    SciTech Connect

    Riga, Celia V. Bicknell, Colin D.; Wallace, Daniel; Hamady, Mohamad; Cheshire, Nicholas

    2009-05-15

    To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.

  8. In-situ electrochemical transmission electron microscopy for battery research.

    PubMed

    Mehdi, B Layla; Gu, Meng; Parent, Lucas R; Xu, Wu; Nasybulin, Eduard N; Chen, Xilin; Unocic, Raymond R; Xu, Pinghong; Welch, David A; Abellan, Patricia; Zhang, Ji-Guang; Liu, Jun; Wang, Chong-Min; Arslan, Ilke; Evans, James; Browning, Nigel D

    2014-04-01

    The recent development of in-situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in-situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in-situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.

  9. In-Situ Resource Utilization (ISRU) Development Program

    NASA Technical Reports Server (NTRS)

    Sanders, Jerry

    1998-01-01

    The question "Why In-Situ Resource Utilization (ISRU)?" is addressed in this presentation. The reasons given concentrate on Cost reduction, Mass reduction, Risk reduction, the expansion of human exploration and presence and the enabling of industrial exploitation. A review of the Martian and Lunar resources available for ISRU is presented. Other ISRU concepts (i.e., In-Situ Consumable production (ISCP) and In-Situ Propellant Production (ISPP)) are introduced and further explained. The objectives of a Mars ISRU System Technology (MIST) include (1) the characterization of technology and subsystem performance for mission modeling and technology funding planning, (2) reduce risk and concerns arising from sample return and human missions utilizing ISRU, and (3) demonstrate the environmental suitability of ISRU components/processes and systems. A proof of concept demonstration schedule and a facility overview for MIST is presented.

  10. In Situ Electrochemical Transmission Electron Microscopy for Battery Research

    SciTech Connect

    Mehdi, Beata L.; Gu, Meng; Parent, Lucas R.; Xu, Wu; Nasybulin, Eduard N.; Chen, Xilin; Unocic, Raymond R.; Xu, Pinghong; Welch, David A.; Abellan, Patricia; Zhang, Jiguang; Liu, Jun; Wang, Chong M.; Arslan, Ilke; Evans, James E.; Browning, Nigel D.

    2014-04-01

    The recent development of in situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.

  11. Design, fabrication, and applications of in situ fluid cell TEM.

    PubMed

    Li, Dongsheng; Nielsen, Michael H; De Yoreo, James J

    2013-01-01

    In situ fluid cell TEM is a powerful new tool for understanding dynamic processes during liquid phase chemical reactions, including mineral formation. This technique, which operates in the high vacuum of a TEM chamber, provides information on crystal structure, phase, morphology, size, aggregation/segregation, and crystal growth mechanisms in real time. In situ TEM records both crystal structure and morphology at spatial resolutions down to the atomic level with high temporal resolution of up to 10(-6)s per image, giving it distinct advantages over other in situ techniques such as optical microscopy, AFM, or X-ray scattering or diffraction. This chapter addresses the design, fabrication, and assembly of TEM fluid cells and applications of fluid cell TEM to understanding mechanisms of mineralization. © 2013 Elsevier Inc. All rights reserved.

  12. In situ biodegradation: Microbiological patterns in a contaminated aquifer

    SciTech Connect

    Madsen, E.L.; Sinclair, J.L.; Ghiorse, W.C. )

    1991-05-10

    Conventional approaches for proving in situ biodegradation of organic pollutants in aquifers have severe limitations. In the approach described here, patterns in a comprehensive set of microbiological activity and distribution data were analyzed. Measurements were performed on sediment samples gathered at consistent depths in aquifer boreholes spanning a gradient of contaminant concentrations at a buried coal tar site. Microbial adaptation to polyaromatic hydrocarbons (PAHs) was demonstrated by mineralization of naphthalene and phenanthrene in samples from PAH-contaminated, but not adjacent pristine, zones. Furthermore, contaminant-stimulated in situ bacterial growth was indicated because enhanced numbers of protozoa and their bacterial prey were found exclusively in contaminated subsurface samples. The data suggest that many convergent lines of logically linked indirect evidence can effectively document in situ biodegradation of aquifer contaminants.

  13. Master of Puppets: Cooperative Multitasking for In Situ Processing

    SciTech Connect

    Morozov, Dmitriy; Lukic, Zarija

    2016-01-01

    Modern scientific and engineering simulations track the time evolution of billions of elements. For such large runs, storing most time steps for later analysis is not a viable strategy. It is far more efficient to analyze the simulation data while it is still in memory. Here, we present a novel design for running multiple codes in situ: using coroutines and position-independent executables we enable cooperative multitasking between simulation and analysis, allowing the same executables to post-process simulation output, as well as to process it on the fly, both in situ and in transit. We present Henson, an implementation of our design, and illustrate its versatility by tackling analysis tasks with different computational requirements. This design differs significantly from the existing frameworks and offers an efficient and robust approach to integrating multiple codes on modern supercomputers. The techniques we present can also be integrated into other in situ frameworks.

  14. In-situ analysis of optically thick nanoparticle clouds

    NASA Astrophysics Data System (ADS)

    Kirchschlager, F.; Wolf, S.; Greiner, F.; Groth, S.; Labdon, A.

    2017-04-01

    Nanoparticles grown in reactive plasmas and nanodusty plasmas gain high interest from basic science and technology. One of the great challenges of nanodusty plasmas is the in-situ diagnostic of the nanoparticle size and refractive index. The analysis of scattered light by means of the Mie solution of the Maxwell equations was proposed and used as an in-situ size diagnostic during the past two decades. Today, imaging ellipsometry techniques and the investigation of dense, i.e., optically thick nanoparticle clouds demand for analysis methods to take multiple scattering into account. We present the first 3D Monte-Carlo polarized radiative transfer simulations of the scattered light in a dense nanodusty plasma. This technique extends the existing diagnostic methods for the in-situ analysis of the properties of nanoparticles to systems where multiple scattering cannot be neglected.

  15. Manipulating Bacterial Communities by in situ Microbiome Engineering

    PubMed Central

    Sheth, Ravi U.; Cabral, Vitor; Chen, Sway P.; Wang, Harris H.

    2016-01-01

    Microbial communities inhabit our entire planet and play a crucial role in biogeochemical processes, agriculture, biotechnology, and human health. Here, we argue that “in situ microbiome engineering” represents a new paradigm of community-scale genetic and microbial engineering. We discuss contemporary applications of this approach to directly add, remove, or modify specific sets of functions and alter community-level properties in terrestrial, aquatic, and host-associated microbial communities. Specifically, we highlight emerging in situ genome engineering approaches as tractable techniques to manipulate microbial communities with high specificity and efficacy. Finally, we describe opportunities for technological innovation and ways to bridge existing knowledge gaps to accelerate the development of in situ approaches for microbiome manipulations. PMID:26916078

  16. Stabilization of contaminated soils by in situ vitrification

    SciTech Connect

    Jacobs, G.K.; Spalding, B.P.; Tixier, J.S.; Powell, T.D.

    1992-12-31

    In situ methods are preferred for the stabilization or restoration of soil sites contaminated with elevated levels of hazardous materials (e.g., radionuclides, metals, organics) to minimize potential risks to personnel and the environment associated with removal and treatment. In situ methods available include polymer and silicate grouting, compaction, chemical treatment, groundwater diversion, and vitrification. Of these, in situ vitrification (ISV) is most desirable because it is more a permanent solution and produces a final waste form with the most preferred characteristics. The ISV product, generally a mixture of glass and crystals, has high strength, is resistant to leaching, and has low porosity and permeability. Results are presented on an ISV test at an Oak Ridge Laboratory Site.

  17. Stabilization of contaminated soils by in situ vitrification

    SciTech Connect

    Jacobs, G.K.; Spalding, B.P. ); Tixier, J.S.; Powell, T.D. )

    1992-01-01

    In situ methods are preferred for the stabilization or restoration of soil sites contaminated with elevated levels of hazardous materials (e.g., radionuclides, metals, organics) to minimize potential risks to personnel and the environment associated with removal and treatment. In situ methods available include polymer and silicate grouting, compaction, chemical treatment, groundwater diversion, and vitrification. Of these, in situ vitrification (ISV) is most desirable because it is more a permanent solution and produces a final waste form with the most preferred characteristics. The ISV product, generally a mixture of glass and crystals, has high strength, is resistant to leaching, and has low porosity and permeability. Results are presented on an ISV test at an Oak Ridge Laboratory Site.

  18. Extreme Spectroscopy: In situ nuclear materials behavior from optical data

    SciTech Connect

    Guimbretiere, G.; Canizares, A.; Raimboux, N.; Omnee, R.; Duval, F.; Ammar, M.R.; Simon, P.; Desgranges, L.; Mohun, R.; Jegou, C.; Magnin, M.

    2015-07-01

    In the nuclear industry, materials are regularly exposed to high temperature or/and irradiation and a better knowledge and understanding of their behavior under such extreme conditions is a key-point for improvements and further developments. Nowadays, Raman spectroscopy begins to be well known as a promising technique in the post mortem and remote characterization of nuclear materials exposed to extreme conditions. On this topic, at ANIMMA 2013 conference, we have presented some results about its implementation in the study of model or real nuclear fuel. However, the strength of Raman spectroscopy as in situ characterization tool is mainly its ability to be implemented remotely through optical fibers. Aware of this, implementation of other optical techniques can be considered in order to gain information not only on the structural dynamics of materials but also on the electronic charge carrier populations. In this paper, we propose to present our last advances in Raman characterization of nuclear materials and enlarge to the in situ use of complementary optical spectroscopies. Emphasis will be made on the information that can be gained to the behavior of the model fuel depleted UO{sub 2} under extreme conditions of high temperature and ionic irradiation: - In Situ Raman identification of the radiolysis alteration products of UO{sub 2} in contact with water under ionic irradiation. - In Situ Raman recording of the damaged dynamic of UO{sub 2} under inert atmosphere. - In Situ Raman and photo-luminescence study of virgin and damaged UO2 at high temperature. - In Situ study of electronic charge carriers' behavior in U{sub x}Th{sub 1-x}O{sub 2} solid solutions by mean of Iono- and Thermo- luminescence under and post- ionic irradiation. (authors)

  19. In-situ Rock Spalling Strength near Excavation Boundaries

    NASA Astrophysics Data System (ADS)

    Cai, M.; Kaiser, P. K.

    2014-03-01

    It is widely accepted that the in-situ strength of massive rocks is approximately 0.4 ± 0.1 UCS, where UCS is the uniaxial compressive strength obtained from unconfined tests using diamond drilling core samples with a diameter around 50 mm. In addition, it has been suggested that the in-situ rock spalling strength, i.e., the strength of the wall of an excavation when spalling initiates, can be set to the crack initiation stress determined from laboratory tests or field microseismic monitoring. These findings were supported by back-analysis of case histories where failure had been carefully documented, using either Kirsch's solution (with approximated circular tunnel geometry and hence σ max = 3σ 1 -σ 3) or simplified numerical stress modeling (with a smooth tunnel wall boundary) to approximate the maximum tangential stress σ max at the excavation boundary. The ratio of σ max /UCS is related to the observed depth of failure and failure initiation occurs when σ max is roughly equal to 0.4 ± 0.1 UCS. In this article, it is suggested that these approaches ignore one of the most important factors, the irregularity of the excavation boundary, when interpreting the in-situ rock strength. It is demonstrated that the "actual" in-situ spalling strength of massive rocks is not equal to 0.4 ± 0.1 UCS, but can be as high as 0.8 ± 0.05 UCS when surface irregularities are considered. It is demonstrated using the Mine-by tunnel notch breakout example that when the realistic "as-built" excavation boundary condition is honored, the "actual" in-situ rock strength, given by 0.8 UCS, can be applied to simulate progressive brittle rock failure process satisfactorily. The interpreted, reduced in-situ rock strength of 0.4 ± 0.1 UCS without considering geometry irregularity is therefore only an "apparent" rock strength.

  20. Drilling-induced core fractures and in situ stress

    NASA Astrophysics Data System (ADS)

    Li, Yongyi; Schmitt, Douglas R.

    1998-03-01

    The relationship between the shapes of drilling-induced core fractures and the in situ state of stress is developed. The stress concentrations at the well bore bottom are first determined using a complete three-dimensional finite element analysis. Existing in situ compressional stresses generate large tensions in the immediate vicinity of the bottom hole which are sufficient to rupture the rock. Tensile fracture trajectories within these concentrated stress fields are predicted using a simple model of fracture propagation. These modeled fracture trajectories resemble well the observed shapes of drilling-induced core disking, petal, and petal-centerline fractures. Further, this agreement suggests that both the shape of the drilling-induced fracture and the location at which it initiates depends on the in situ stress state existing in the rock mass prior to drilling; the core fractures contain substantial information on in situ stress conditions. In all faulting regimes the coring-induced fractures initiate near the bit cut except for most cases under thrust faulting regime where the fracture initiates on the well bore axis. Further, under thrust faulting conditions only disk fractures appear possible. Both petal and disking fractures can be produced in strike-slip and normal faulting regimes depending upon the relative magnitudes between the least compressive horizontal principal stress and the vertical overburden stress. The predicted fracture shapes are in good qualitative agreement with observations of drilling-induced fractures described in the literature from laboratory experiments and field programs in which in situ stresses are measured by other means. The relationship of the morphology of coring induced fractures and in situ stresses suggests that the fractures can be used as independent complementary indicators in identifying stress regimes.

  1. In-situ bioremediation drilling and characterization work plan

    SciTech Connect

    Koegler, K.J.

    1994-04-26

    This work plan describes the design and construction of proposed wells and outlines the characterization activities to be performed in support of the In Situ Bioremediation Task for FY 1994. The purpose of the well-design is to facilitate implementation and monitoring of in situ biodegradation of CCl{sub 4} in ground water. However, the wells will also be used to characterize the geology, hydrology, microbiology, and contaminant distribution, which will all feed into the design of the technology. Implementation and design of this remediation demonstration technology will be described separately in an integrated test plan.

  2. In Situ Characterization of Ge Nanocrystals Near the Growth Temperature

    SciTech Connect

    Sharp, I.D.; Xu, Q.; Liao, C.Y.; Chrzan, D.C.; Haller, E.E.; Yi, D.O.; Beeman, J.W.; Liliental-Weber, Z.; Yu, K.M.; Zakharov, D.N.; Ager, J.W. III

    2005-06-30

    We present in situ electron diffraction data indicating that Ge nanocrystals embedded in a silica matrix can be solid at temperatures exceeding the bulk Ge melting point. Supercooling is observed when returning from temperatures above the melting point of the Ge nanocrystals. Since melting point hysteresis is observed, it is not clear if nanoclusters are solid or liquid during the initial growth process. Raman spectra of as-grown nanocrystals give a measure of compressive stress and in-situ Raman spectroscopy further confirms the presence of crystalline Ge above 800 deg. C.

  3. Electrochemical atomic force microscopy: In situ monitoring of electrochemical processes

    NASA Astrophysics Data System (ADS)

    Reggente, Melania; Passeri, Daniele; Rossi, Marco; Tamburri, Emanuela; Terranova, Maria Letizia

    2017-08-01

    The in-situ electrodeposition of polyaniline (PANI), one of the most attractive conducting polymers (CP), has been monitored performing electrochemical atomic force microscopy (EC-AFM) experiments. The electropolymerization of PANI on a Pt working electrode has been observed performing cyclic voltammetry experiments and controlling the evolution of current flowing through the electrode surface, together with a standard AFM image. The working principle and the potentialities of this emerging technique are briefly reviewed and factors limiting the studying of the in-situ electrosynthesis of organic compounds discussed.

  4. In situ analysis of DNA methylation in plants.

    PubMed

    Kathiria, Palak; Kovalchuk, Igor

    2010-01-01

    Epigenetic changes in the plant genome are associated with differential genome methylation, histone modifications, and the binding of various chromatin-binding factors. Methylation of cytosine residues is one of the most versatile mechanisms of epigenetic regulation. The analysis of DNA methylation can be performed in different ways. However, most of these procedures involve the extraction of chromatin from cells with further isolation and analysis of DNA. Modest success has been achieved in DNA methylation analysis in plant tissues in situ. Here, we present an in situ method for DNA methylation analysis, which has high sensitivity and good reproducibility.

  5. Electrochemical cell for in-situ x-ray characterization

    SciTech Connect

    Doughty, D.H.; Ingersoll, D.; Rodriguez, M.A.

    1998-08-04

    An electrochemical cell suitable for in-situ XRD analysis is presented. Qualitative information such as phase formation and phase stability can be easily monitored using the in-situ cell design. Quantitative information such as lattice parameters and kinetic behavior is also straightforward. Analysis of the LiMn&sub2;O&sub4; spinel using this cell design shows that the lattice undergoes two major structural shrinkages at approx. 4.0 V and approx. 4.07 V during charging. These shrinkages correlate well with the two electrochemical waves observed and indicate the likelihood of two separate redox processes which charging and discharging.

  6. In situ evaporation of lithium for LEVIS ion source

    SciTech Connect

    Gerber, B.; Lopez, M.; Lamppa, K.; Stearns, W.; Bieg, K.

    1994-05-01

    This report describes the In Situ evaporation of pure lithium on the anode of PBFA II which then can be evaporated and ionized by Laser Evaporation and Ionization Source (LEVIS). Included in this report are the necessary calculations, light laboratory experiments and details of the hardware for PBFA II. This report gives all the details of In Situ evaporation for PBFA II so when a decision is made to provide an active lithium source for PBFA II, it can be fielded in a minimum of time.

  7. A simplified In Situ cosmogenic 14C extraction system

    USGS Publications Warehouse

    Pigati, J.S.; Lifton, N.A.; Timothy, Jull A.J.; Quade, Jay

    2010-01-01

    We describe the design, construction, and testing of a new, simplified in situ radiocarbon extraction system at the University of Arizona. Blank levels for the new system are low ((234 ?? 11) ?? 103 atoms (1 ??; n = 7)) and stable. The precision of a given measurement depends on the concentration of 14C, but is typically <5% for concentrations of 100 ?? 103 atoms g-1 or more. The new system is relatively small and easy to construct, costs significantly less than the original in situ 14C extraction system at Arizona, and lends itself to future automation. ?? 2010 by the Arizona Board of Regents on behalf of the University of Arizona.

  8. Fluorescent in situ hybridization protocols in Drosophila embryos and tissues.

    PubMed

    Lécuyer, Eric; Parthasarathy, Neela; Krause, Henry M

    2008-01-01

    Fluorescent in situ hybridization is the standard method for visualizing the spatial distribution of RNA. Although traditional histochemical RNA detection methods suffered from limitations in resolution or sensitivity, the recent development of peroxidase-mediated tyramide signal amplification provides strikingly enhanced sensitivity and subcellular resolution. In this chapter, we describe optimized fluorescent in situ hybridization protocols for Drosophila embryos and tissues utilizing tyramide signal amplification, either for single genes or in a high-throughput format, which greatly increases the sensitivity, consistency, economy, and throughput of the procedure. We also describe variations of the method for RNA-RNA and RNA-protein codetection.

  9. Single cylinder in situ scanning electron microscope fatigue system

    SciTech Connect

    Smiltneek, Larry; Shinde, Sachin R.; Hoeppner, David W.

    2006-01-15

    This article introduces a single cylinder fatigue machine adaptable to a scanning electron microscope chamber. The machine includes a node control mechanism to create a still observation node at any location on the specimen as fatigue cycling occurs, thereby allowing a point of interest to remain within view. The exceptional stability of this machine enables improved in situ study of the fatigue cracking phenomenon. For example, an in situ machine enhances the researcher's ability to record material structural changes that precede crack nucleation and allows observation of the influences of microstructure (grain structure) on the early stages of crack propagation.

  10. Continued Development of in Situ Geochronology for Planetary Missions

    NASA Technical Reports Server (NTRS)

    Devismes, D.; Cohen, B. A.

    2015-01-01

    The instrument 'Potassium (K) Argon Laser Experiment' (KArLE) is developed and designed for in situ absolute dating of rocks on planetary surfaces. It is based on the K-Ar dating method and uses the Laser Induced Breakdown Spectroscopy - Laser Ablation - Quadrupole Mass Spectrometry (LIBSLA- QMS) technique. We use a dedicated interface to combine two instruments similar to SAM of Mars Science Laboratory (for the QMS) and ChemCam (for the LA and LIBS). The prototype has demonstrated that KArLE is a suitable and promising instrument for in situ absolute dating.

  11. In Situ Characterization of Ge Nanocrystals Near the Growth Temperature

    NASA Astrophysics Data System (ADS)

    Sharp, I. D.; Xu, Q.; Yi, D. O.; Liao, C. Y.; Beeman, J. W.; Liliental-Weber, Z.; Yu, K. M.; Zakharov, D. N.; Ager, J. W.; Chrzan, D. C.; Haller, E. E.

    2005-06-01

    We present in situ electron diffraction data indicating that Ge nanocrystals embedded in a silica matrix can be solid at temperatures exceeding the bulk Ge melting point. Supercooling is observed when returning from temperatures above the melting point of the Ge nanocrystals. Since melting point hysteresis is observed, it is not clear if nanoclusters are solid or liquid during the initial growth process. Raman spectra of as-grown nanocrystals give a measure of compressive stress and in-situ Raman spectroscopy further confirms the presence of crystalline Ge above 800 °C.

  12. In situ bioremediation strategies for organic wood preservatives

    SciTech Connect

    Mueller, J.G.; Tischuk, M.D.; Brourman, M.D.; Steeg, G.E. Van De

    1995-12-31

    Laboratory biotreatability studies evaluated the use of bioventing and biosparging plus groundwater circulation (UVB technology) for their potential ability to treat soil and groundwater containing creosote and pentachlorophenol. Soils from two former wood-treatment facilities were used in these studies. These studies provided useful, site-specific data demonstrating enhanced biodegradation of all monitored organic constituents. The results suggest that the introduction and delivery of co-reagents (i.e., oxygen and nitrogen) essential to in situ biodegradation of organic wood preservatives represents an important component of effective in situ bioremediation. Full-scale implementation strategies are being considered based on the findings of these studies.

  13. Multiple excitation fluorometer for in situ oceanographic applications.

    PubMed

    Desiderio, R A; Moore, C; Lantz, C; Cowles, T J

    1997-02-20

    A new in situ fluorometer for the detection of oceanic photosynthetic pigment fluorescence is described. Emission spectra from 546 to 733 nm are recorded for each of three different visible excitation bands ten times a second. A Spectralon cell is used to improve the excitation coupling to and the collection efficiency from the sample volume. Laboratory tests demonstrated that the fluorescence emission spectra from the violet, blue, and green excitation can be used to discriminate among various algal species. The instrument was used at sea in extended in situ deployments on an undulating vehicle (SeaSoar).

  14. DNA sequence mapping by fluorescence in situ hybridization

    SciTech Connect

    Brandriff, B.F.; Gordon, L.A.; Trask, B.J. )

    1991-01-01

    Various types of DNA probes, such as total genomic DNA, repetitive sequences, unique sequences, and composites of chromosome-specific DNA probes, can be used with fluorescence in situ hybridization (FISH) techniques to address research questions having to do with localization, mapping, and distribution of DNA in situ. FISH involves the formation of a heteroduplex between such DNA probes and chromatin targets on a microscope slide, which can be visualized with fluorescent reporter molecules. Three chromatin targets - metaphase chromosomes, somatic interphases, and zygote interphases - offer increasingly extended states of chromatin which can be strategically selected, individually or in combination, to address specific research questions of interest.

  15. In-situ measurements of lunar heat flow

    NASA Technical Reports Server (NTRS)

    Langseth, M. G.; Keihm, S. J.

    1974-01-01

    During the Apollo program two successful heat flow measurements were made in situ on the lunar surface. At the Apollo 15 site a value of 0.0000031 watts/sqcm was measured and at the Apollo 17 site a value of 0.0000022 watts/sqcm was determined. Both measurements have uncertainty limits of + or - 20% and have been corrected for perturbing topographic effects. The apparent difference between the observations may correlate with observed variations in the surface abundance of thorium. Comparison with earlier determinations of heat flow, using the microwave emission spectrum from the moon, gives support to the high gradients and heat flows observed in situ.

  16. In-situ measurements of lunar heat flow

    NASA Technical Reports Server (NTRS)

    Langseth, M. B.; Keihm, S. J.

    1977-01-01

    During the Apollo program two successful heat flow measurements were made in situ on the lunar surface. At the Apollo 15 site a value of .0000031 W/sq cm was measured, and at the Apollo 17 site a value of .0000022 W/sq cm was determined. Both measurements have uncertainty limits of + or - 20 percent and have been corrected for perturbing topographic effects. The apparent difference between the observations may correlate with observed variations in the surface abundance of thorium. Comparison with earlier determinations of heat flow, using the microwave emission spectrum from the moon, gives support to the high gradients and heat flows observed in situ.

  17. Method for forming an in situ oil shale retort

    SciTech Connect

    Cha, C.Y.

    1983-01-11

    An in situ oil shale retort is formed in a subterranean formation containing oil shale, a horizontally extending void is excavated within the boundaries of the retort site leaving a zone of unfragmented formation above and/or below such a void. A crack is propagated in at least one of the zones of unfragmented formation along the side boundaries of the retort site and thereafter the zone of unfragmented formation is explosively expanded towards such a void for forming a fragmented permeable mass of formation particles in the retort. Such a fragmented permeable mass is retorted in situ to produce shale oil.

  18. Triple redundant hydrogen sensor with in situ calibration

    NASA Technical Reports Server (NTRS)

    Lantz, J. B.; Powell, J. D.; Schubert, F. H.; Koszenski, E. P.

    1980-01-01

    To meet sensing and calibration needs, an in situ calibration technique was developed. It is based on electrolytic generation of a hydrogen/air atmosphere within a hydrogen sensor. The hydrogen is generated from water vapor in the air, and being electrical in nature, the in situ calibration can be performed completely automatically in remote locations. Triply redundant sensor elements are integrated within a single, compact housing, and digital logic provides inter-sensor comparisons to warn of and identify malfunctioning sensor elements. An evaluation of this concept is presented.

  19. Subsurface In Situ Elemental Composition Measurements with PING

    NASA Technical Reports Server (NTRS)

    Parsons, Ann; McClanahan, Timothy; Bodnarik, Julia; Evans, Larry; Nowicki, Suzanne; Schweitzer, Jeffrey; Starr, Richard

    2013-01-01

    This paper describes the Probing In situ with Neutron and Gamma rays (PING) instrument, that can measure the subsurface elemental composition in situ for any rocky body in the solar system without the need for digging into the surface. PING consists of a Pulsed Neutron Generator (PNG), a gamma ray spectrometer and neutron detectors. Subsurface elements are stimulated by high-energy neutrons to emit gamma rays at characteristic energies. This paper will show how the detection of these gamma rays results in a measurement of elemental composition. Examples of the basalt to granite ratios for aluminum and silicon abundance are provided.

  20. Engineered approaches for in situ bioremediation of chlorinated solvent contamination

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1999-11-01

    Throughout the world there are sites contaminated with chlorinated compounds such as perchloroethylene, trichloroethylene, tetrachloromethene, carbon tetrachloride, pentachlorophenol, chlorinated benzenes, and various pesticide/herbicide compounds. Not only do these compounds carry health risks, but they also are challenging and often expensive to treat in the field. However, progress is being made, and this volume brings together the most up-to-date laboratory findings and the latest full-scale results from bioremediation efforts at actual field sites. Engineering approaches discussed include biobarriers, cometabolism, bioaugmentation, in situ oxidation, Genton`s Reagent, in situ bioremediation, and more.

  1. Strategies for In situ and Sample Return Analyses

    NASA Astrophysics Data System (ADS)

    Papanastassiou, D. A.

    2006-12-01

    There is general agreement that planetary exploration proceeds from orbital reconnaissance of a planet, to surface and near-surface in situ exploration, to sample return missions, which bring back samples for investigations in terrestrial laboratories, using the panoply of state-of-the-art analytical techniques. The applicable techniques may depend on the nature of the returned material and complementary and multi- disciplinary techniques can be used to best advantage. High precision techniques also serve to provide the "ground truth" and calibrate past and future orbital and in situ measurements on a planet. It is also recognized that returned samples may continue to be analyzed by novel techniques as the techniques become developed, in part to address specific characteristics of returned samples. There are geophysical measurements such as those of the moment of inertia of a planet, seismic activity, and surface morphology that depend on orbital and in-situ science. Other characteristics, such as isotopic ages and isotopic compositions (e.g., initial Sr and Nd) as indicators of planetary mantle or crust evolution and sample provenance require returned samples. In situ analyses may be useful for preliminary characterization and for optimization of sample selection for sample return. In situ analyses by Surveyor on the Moon helped identify the major element chemistry of lunar samples and the need for high precision mass spectrometry (e. g., for Rb-Sr ages, based on extremely low alkali contents). The discussion of in-situ investigations vs. investigations on returned samples must be directly related to available instrumentation and to instrumentation that can be developed in the foreseeable future. The discussion of choices is not a philosophical but instead a very practical issue: what precision is required for key investigations and what is the instrumentation that meets or exceeds the required precision. This must be applied to potential in situ instruments and

  2. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques

    SciTech Connect

    Lovley, Derek R

    2012-11-28

    The goal of these projects was to develop molecule tools to tract the metabolic activity and physiological status of microorganisms during in situ uranium bioremediation. Such information is important in able to design improved bioremediation strategies. As summarized below, the research was highly successful with new strategies developed for estimating in situ rates of metabolism and diagnosing the physiological status of the predominant subsurface microorganisms. This is a first not only for groundwater bioremediation studies, but also for subsurface microbiology in general. The tools and approaches developed in these studies should be applicable to the study of microbial communities in a diversity of soils and sediments.

  3. In situ production of solar power systems for exploration: Potential for in situ rectenna production on Mars

    NASA Astrophysics Data System (ADS)

    Curreri, Peter A.; Criswell, David R.

    1999-01-01

    In situ derived expandable power is a key to eventual Mars base self-sufficiency. Initial studies for a non-nuclear human Mars reference mission rely on a large area of solar cells with energy storage for night power requirements. Preliminary studies indicate that utilization of Solar Electric Propulsion vehicles in Mars areosynchronous orbit might competitively provide continuous power if laser or 245 GHz microwave power transmission were utilized. This paper looks at the potential to reduce landed mass on Mars for a non-nuclear human mission and thus reduce mission cost by making the power receiving rectennas in situ on Mars surface.

  4. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques

    SciTech Connect

    Lovley, Derek R.

    2012-11-28

    The goal of these projects was to develop molecule tools to tract the metabolic activity and physiological status of microorganisms during in situ uranium bioremediation. Such information is important in able to design improved bioremediation strategies. As summarized below, the research was highly successful with new strategies developed for estimating in situ rates of metabolism and diagnosing the physiological status of the predominant subsurface microorganisms. This is a first not only for groundwater bioremediation studies, but also for subsurface microbiology in general. The tools and approaches developed in these studies should be applicable to the study of microbial communities in a diversity of soils and sediments.

  5. In situ nonlinear elastic behavior of soil observed by DAET

    SciTech Connect

    Larmat, Carene; Renaud, Guillaume; Rutledge, James T.; Lee, Richard C.; Guyer, Robert A.; Johnson, Paul A.

    2012-07-05

    The key to safe design of critical facilities (strong ground motion in low velocity materials such as soils). Current approaches are predictions from measurements of the elastic non-linear properties of boreholes samples. Need for in-situ, local and complete determination of non-linear properties of soil, rock in response to high-strain motion.

  6. In situ studies of velocity in fractured crystalline rocks.

    USGS Publications Warehouse

    Moos, D.; Zoback, M.D.

    1983-01-01

    A study of the effects of macroscopic fractures on P and S wave velocities has been conducted in four wells drilled in granitic rock to depths between 0.6 and 1.2km. The effect of macroscopic fractures is to decrease both Vp and Vs and increase Vp/Vs. In wells with a relatively low density of macroscopic fractures, the in situ velocity is similar to that of saturated core samples under confining pressure in the laboratory, and there is a clear correlation between zones with macroscopic fractures and anomalously low velocities. In wells with numerous macroscopic fractures, the in situ velocity is lower than that of intact samples under pressure, and there is a correlation between the rate at which in situ velocity increases with depth and the rate at which the velocity of laboratory samples increases with pressure. Differences in in situ P wave velocity between wells cannot be explained solely by differences in the degree of macroscopic fracturing, thus emphasizing the importance of composition and microcracks on velocity.-from Authors

  7. SITE TECHNOLOGY CAPSULE: IN SITU STEAM ENHANCED RECOVERY PROCESS

    EPA Science Inventory

    The SERP technology is designed to treat soils contaminated with VOCs and SVOCs in situ. Steam injection and vacuum extraction are used to remove the organic compounds from the soil and concentrate them for disposal or recycling. A full-scale demonstration of SERP was conducted a...

  8. In situ spectrophotometric measurement of dissolved inorganic carbon in seawater

    USGS Publications Warehouse

    Liua, Xuewu; Byrne, Robert H.; Adornato, Lori; Yates, Kimberly K.; Kaltenbacher, Eric; Ding, Xiaoling; Yang, Bo

    2013-01-01

    Autonomous in situ sensors are needed to document the effects of today’s rapid ocean uptake of atmospheric carbon dioxide (e.g., ocean acidification). General environmental conditions (e.g., biofouling, turbidity) and carbon-specific conditions (e.g., wide diel variations) present significant challenges to acquiring long-term measurements of dissolved inorganic carbon (DIC) with satisfactory accuracy and resolution. SEAS-DIC is a new in situ instrument designed to provide calibrated, high-frequency, long-term measurements of DIC in marine and fresh waters. Sample water is first acidified to convert all DIC to carbon dioxide (CO2). The sample and a known reagent solution are then equilibrated across a gas-permeable membrane. Spectrophotometric measurement of reagent pH can thereby determine the sample DIC over a wide dynamic range, with inherent calibration provided by the pH indicator’s molecular characteristics. Field trials indicate that SEAS-DIC performs well in biofouling and turbid waters, with a DIC accuracy and precision of ∼2 μmol kg–1 and a measurement rate of approximately once per minute. The acidic reagent protects the sensor cell from biofouling, and the gas-permeable membrane excludes particulates from the optical path. This instrument, the first spectrophotometric system capable of automated in situ DIC measurements, positions DIC to become a key parameter for in situ CO2-system characterizations.

  9. Accelerating in Situ Endothelialisation of Cardiovascular Bypass Grafts

    PubMed Central

    Goh, Ee Teng; Wong, Eleanor; Farhatnia, Yasmin; Tan, Aaron; Seifalian, Alexander M.

    2014-01-01

    The patency of synthetic cardiovascular grafts in the long run is synonymous with their ability to inhibit the processes of intimal hyperplasia, thrombosis and calcification. In the human body, the endothelium of blood vessels exhibits characteristics that inhibit such processes. As such it is not surprising that research in tissue engineering is directed towards replicating the functionality of the natural endothelium in cardiovascular grafts. This can be done either by seeding the endothelium within the lumen of the grafts prior to implantation or by designing the graft such that in situ endothelialisation takes place after implantation. Due to certain difficulties identified with in vitro endothelialisation, in situ endothelialisation, which will be the focus of this article, has garnered interest in the last years. To promote in situ endothelialisation, the following aspects can be taken into account: (1) Endothelial progenital cell mobilization, adhesion and proliferation; (2) Regulating differentiation of progenitor cells to mature endothelium; (3) Preventing thrombogenesis and inflammation during endothelialisation. This article aims to review and compile recent developments to promote the in situ endothelialisation of cardiovascular grafts and subsequently improve their patency, which can also have widespread implications in the field of tissue engineering. PMID:25551605

  10. SITE TECHNOLOGY CAPSULE: IN SITU STEAM ENHANCED RECOVERY PROCESS

    EPA Science Inventory

    The SERP technology is designed to treat soils contaminated with VOCs and SVOCs in situ. Steam injection and vacuum extraction are used to remove the organic compounds from the soil and concentrate them for disposal or recycling. A full-scale demonstration of SERP was conducted a...

  11. In situ nanoindentation in a transmission electron microscope

    SciTech Connect

    Minor, Andrew M.

    2002-01-01

    This dissertation presents the development of the novel mechanical testing technique of in situ nanoindentation in a transmission electron microscope (TEM). This technique makes it possible to simultaneously observe and quantify the mechanical behavior of nano-scale volumes of solids.

  12. IN-SITU FENTON OXIDATION: A CRITICAL ANALYSIS

    EPA Science Inventory

    In-situ Fenton oxidation (ISFO) is a rapidly emerging technology which involves the injection of hydrogen peroxide (H2O2) and other chemical reagents into the subsurface for the purpose of oxidizing and transforming contaminants. ISFO is being applied at an increasing number of ...

  13. Method of making in-situ whisker reinforced glass ceramic

    DOEpatents

    Brown, Jesse J.; Hirschfeld, Deidre A.; Lee, K. H.

    1993-02-16

    A heat processing procedure is used to create reinforcing whiskers of TiO.sub.2 in glass-ceramic materials in the LAS and MAS family. The heat processing procedure has particular application in creating TiO.sub.2 in-situ in a modified .beta.-eucryptite system.

  14. In Situ Resource Utilization (ISRU 3) Technical Interchange Meeting: Abstracts

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This volume contains abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU III) Technical Interchange Meeting, February 11-12, 1999, hosted by the Lockheed Martin Astronautics Waterton Facility, Denver, Colorado. Administration and publication support for this meeting were provided by the staff of the Publications and Program Services Department at the Lunar and Planetary Institute.

  15. Applied in situ product recovery in ABE fermentation

    PubMed Central

    Lalander, Carl‐Axel; Lee, Jonathan G. M.; Davies, E. Timothy; Harvey, Adam P.

    2017-01-01

    The production of biobutanol is hindered by the product's toxicity to the bacteria, which limits the productivity of the process. In situ product recovery of butanol can improve the productivity by removing the source of inhibition. This paper reviews in situ product recovery techniques applied to the acetone butanol ethanol fermentation in a stirred tank reactor. Methods of in situ recovery include gas stripping, vacuum fermentation, pervaporation, liquid–liquid extraction, perstraction, and adsorption, all of which have been investigated for the acetone, butanol, and ethanol fermentation. All techniques have shown an improvement in substrate utilization, yield, productivity or both. Different fermentation modes favored different techniques. For batch processing gas stripping and pervaporation were most favorable, but in fed‐batch fermentations gas stripping and adsorption were most promising. During continuous processing perstraction appeared to offer the best improvement. The use of hybrid techniques can increase the final product concentration beyond that of single‐stage techniques. Therefore, the selection of an in situ product recovery technique would require comparable information on the energy demand and economics of the process. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:563–579, 2017 PMID:28188696

  16. In situ sensor techniques in modern bioprocess monitoring.

    PubMed

    Beutel, Sascha; Henkel, Steffen

    2011-09-01

    New reactor concepts as multi-parallel screening systems or disposable bioreactor systems for decentralized and reproducible production increase the need for new and easy applicable sensor technologies to access data for process control. These sophisticated reactor systems require sensors to work with the lowest sampling volumes or, even better, to measure directly in situ, but in situ sensors are directly incorporated into a reactor or fermenter within the sterility barrier and have therefore to stand the sterilization procedures. Consequently, these in situ sensor technologies should enable the measurement of multi-analytes simultaneously online and in real-time at a low price for the robust sensing element. Current research therefore focuses on the implementation of noninvasive spectroscopic and optical technologies, and tries to employ them through fiber optics attached to disposable sensing connectors. Spectroscopic methods reach from ultraviolet to infrared and further comprising fluorescence and Raman spectroscopy. Also, optic techniques like microscopy are adapted for the direct use in bioreactor systems (Ulber et al. in Anal Bioanal Chem 376:342-348, 2003) as well as various electrochemical methods (Joo and Brown in Chem Rev 108:638-651, 2008). This review shows the variety of modern in situ sensing principles in bioprocess monitoring with emphasis on spectroscopic and optical techniques and the progress in the adaption to latest reactor concepts.

  17. 78 FR 47427 - AUC, LLC Reno Creek, In Situ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-05

    ...By letter dated October 3, 2012, AUC submitted a license application to the U.S. Nuclear Regulatory Commission (NRC) requesting authorization to construct and operate its proposed Reno Creek, In Situ Leach Uranium Recovery (ISR) project to be located in the Powder River Basin near Wright, Wyoming.

  18. In-Situ Pointing Correction and Rover Microlocalization

    NASA Technical Reports Server (NTRS)

    Deen, Robert G.; Lorre, Jean J.

    2010-01-01

    Two software programs, marstie and marsnav, work together to generate pointing corrections and rover micro-localization for in-situ images. The programs are based on the PIG (Planetary Image Geometry) library, which handles all mission dependencies. As a result, there is no mission-specific code in either of these programs. This software corrects geometric seams in images as much as possible.

  19. Terra Vac In Situ Vacuum Extraction System: Applications Analysis Report

    EPA Science Inventory

    This document is an evaluation of the Terra Vac in situ vacuum extraction system and its applicability as a treatment method for waste site cleanup. This report analyzes the results from the Superfund Innovative Technology Evaluation (SITE) Program’s 56-day demonstration at t...

  20. In situ construction of a coordination zirconocene tetrahedron.

    PubMed

    Liu, Guoliang; Ju, Zhanfeng; Yuan, Daqiang; Hong, Maochun

    2013-12-16

    The current study describes the first in situ synthesis and characterization of a new family of cationic coordination tetrahedra of both the V4F4 and V4E6 type, which are constructed by a new building block based on a trinuclear zirconocene moiety and the dicarboxylate or tricarboxylate anions.

  1. 30 CFR 828.11 - In situ processing: Performance standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... contamination of ground and surface waters, damage to fish, wildlife and related environmental values, and threats to the public health and safety. (d) Each person who conducts in situ processing activities shall... processing activities shall restore the quality of affected ground water in the permit area and adjacent area...

  2. Bioprocessing of sweet sorghum with in situ-produced enzymes

    SciTech Connect

    Tengerdy, R.P.; Szakacs, G.; Sipocz, J.

    1996-12-31

    Enzyme-assisted ensiling (ENLAC), using in situ-produced enzymes from Gliocladium sp. TUB-F-498, preserved 80% of the sugar content of sweet sorghum, and facilitated its extraction by countercurrent diffusion. The in situ enzyme was produced on the extracted sweet sorghum pulp by an 8-d solid substrate fermentation (SSF) with a yield of 4.6 cellulose and 400 IU/g dry wt xylanase. Two percent of the fermented substrate had cellulose and xylanase levels equivalent or superior to levels found in the commercial enzymes Celluclast and Viscozyme Novo at the 0.025% application level in ENLAC. The in situ-production of enzymes on recyclable substrates may reduce bioprocessing costs significantly. In this ENLAC process, the cost of the in situ enzymes is estimated to be about $0.12/metric ton (MT) substrate, compared to $9.5/metric ton for the commercial enzymes, a cost reduction of nearly 80-fold. 4 refs., 3 figs., 4 tabs.

  3. FISH-ing for Genes: Modeling Fluorescence "in situ" Hybridization

    ERIC Educational Resources Information Center

    Baker, William P.; Jones, Carleton Buck

    2006-01-01

    Teaching methods of genetic analysis such as fluorescence in situ hybridization (FISH) can be an important part of instructional units in biology, microbiology, and biotechnology. Experience, however, indicates that these topics are difficult for many students. The authors of this article describe how they created an activity that effectively…

  4. Adaptation of in-situ microscopy for crystallization processes

    NASA Astrophysics Data System (ADS)

    Bluma, A.; Höpfner, T.; Rudolph, G.; Lindner, P.; Beutel, S.; Hitzmann, B.; Scheper, T.

    2009-08-01

    In biotechnological and pharmaceutical engineering, the study of crystallization processes gains importance. An efficient analytical inline sensor could help to improve the knowledge about these processes in order to increase efficiency and yields. The in-situ microscope (ISM) is an optical sensor developed for the monitoring of bioprocesses. A new application for this sensor is the monitoring in downstream processes, e.g. the crystallization of proteins and other organic compounds. This contribution shows new aspects of using in-situ microscopy to monitor crystallization processes. Crystals of different chemical compounds were precipitated from supersaturated solutions and the crystal growth was monitored. Exemplified morphological properties and different forms of crystals could be distinguished on the basis of offline experiments. For inline monitoring of crystallization processes, a special 0.5 L stirred tank reactor was developed and equipped with the in-situ microscope. This reactor was utilized to carry out batch experiments for crystallizations of O-acetylsalicyclic acid (ASS) and hen egg white lysozyme (HEWL). During the whole crystallization process, the in-situ microscope system acquired images directly from the crystallization broth. For the data evaluation, an image analysis algorithm was developed and implemented in the microscope analysis software.

  5. In Situ Bioremediation of Perchlorate in Vadose Zone Source Areas

    DTIC Science & Technology

    2011-01-01

    agricultural bags (e.g., ITRC, 2008; Evans et al., 2008). Phytoremediation has also been tested for soil treatment (ITRC, 2008). However, these...within the saturated zone (through in situ bioremediation or groundwater extraction and ex-situ treatment), phytoremediation , which is unlikely to

  6. In situ performance measurements of the mitre photovoltaic array

    NASA Technical Reports Server (NTRS)

    Cherdak, A. S.; Haas, G. M.

    1977-01-01

    A data acquisition system was developed to provide more accurate and consistent measurement of the degradation of solar arrays. A technique was developed for in-situ measurement of photovoltaic panels of sufficient quality to permit evaluation of electrical performance over extended periods of several years.

  7. DEMONSTRATION BULLETIN: IN-SITU VACUUM EXRACTION: TERRA VAC, INC.

    EPA Science Inventory

    This in-situ vacuum extraction technology is a process for the removal and venting of volatile organic compounds (VOCs) from the vadose or unsaturated zone of soils. Often, these compounds can be removed from the vadose zone before they have a chance to contaminate groundwater. ...

  8. In-situ remediation system for groundwater and soils

    DOEpatents

    Corey, J.C.; Kaback, D.S.; Looney, B.B.

    1991-01-01

    The present invention relates to a system for in-situ remediation of contaminated groundwater and soil. In particular the present invention relates to stabilizing toxic metals in groundwater and soil. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.

  9. A Technique for In Situ Ballistic Electron Emission Microscopy

    NASA Astrophysics Data System (ADS)

    Balsano, Robert; Garramone, John; Labella, Vincent

    2012-02-01

    Ballistic electron emission microscopy (BEEM) is a scanning tunneling microscopy (STM) technique that can measure transport of hot electrons through materials and interfaces with high spatial and energetic resolution. BEEM requires an additional contact to ground the metal base layer of a metal semiconductor junction. Performing BEEM in situ with the sample fabrication requires a custom built STM or modifying a commercial one to facilitate the extra contact, which leaves the technique to highly trained experts. This poster will describe our work to develop a special silicon substrate that has the extra contact built in to enable in situ BEEM without modifications to the STM. Electrically isolated contact traces are lithographically patterned ex situ onto the silicon substrate and connected to the BEEM sample plate which is then inserted into the ultra-high vacuum chamber. The metal is then deposited through a shadow mask and then mounted in situ onto the STM for BEEM measurements. BEEM measurements comparing both in situ and ex situ deposited films will be presented.

  10. Volcano Monitor: Autonomous Triggering of In-Situ Sensors

    NASA Technical Reports Server (NTRS)

    Behar, Alberto; Davies, Ashley; Tran, Daniel Q.; Boudreau, Kate; Cecava, Johanna

    2009-01-01

    In-situ sensors near volcanoes would be alerted by the Earth Observing-1 (EO-1) craft to take more frequent data readings. This project involves developing a sulfur-dioxide-sensing volcano monitor that will be able to transmit its readings through an Iridium modem.

  11. In situ remediation of contaminated marinesediment: an overview.

    PubMed

    Lofrano, G; Libralato, G; Minetto, D; De Gisi, S; Todaro, F; Conte, B; Calabrò, D; Quatraro, L; Notarnicola, M

    2017-02-01

    Sediment tends to accumulate inorganic and persistent hydrophobic organic contaminants representing one of the main sinks and sources of pollution. Generally, contaminated sediment poses medium- and long-term risks to humans and ecosystem health; dredging activities or natural resuspension phenomena (i.e., strongly adverse weather conditions) can remobilize pollution releasing it into the water column. Thus, ex situ traditional remediation activities (i.e., dredging) can be hazardous compared to in situ techniques that try to keep to a minimum sediment mobilization, unless dredging is compulsory to reach a desired bathymetric level. We reviewed in situ physico-chemical (i.e., active mixing and thin capping, solidification/stabilization, chemical oxidation, dechlorination, electrokinetic separation, and sediment flushing) and bio-assisted treatments, including hybrid solutions (i.e., nanocomposite reactive capping, bioreactive capping, microbial electrochemical technologies). We found that significant gaps still remain into the knowledge about the application of in situ contaminated sediment remediation techniques from the technical and the practical viewpoint. Only activated carbon-based technologies are well developed and currently applied with several available case studies. The environmental implication of in situ remediation technologies was only shortly investigated on a long-term basis after its application, so it is not clear how they can really perform.

  12. Heat exchanger life extension via in-situ reconditioning

    DOEpatents

    Holcomb, David E.; Muralidharan, Govindarajan

    2016-06-28

    A method of in-situ reconditioning a heat exchanger includes the steps of: providing an in-service heat exchanger comprising a precipitate-strengthened alloy wherein at least one mechanical property of the heat exchanger is degraded by coarsening of the precipitate, the in-service heat exchanger containing a molten salt working heat exchange fluid; deactivating the heat exchanger from service in-situ; in a solution-annealing step, in-situ heating the heat exchanger and molten salt working heat exchange fluid contained therein to a temperature and for a time period sufficient to dissolve the coarsened precipitate; in a quenching step, flowing the molten salt working heat-exchange fluid through the heat exchanger in-situ to cool the alloy and retain a supersaturated solid solution while preventing formation of large precipitates; and in an aging step, further varying the temperature of the flowing molten salt working heat-exchange fluid to re-precipitate the dissolved precipitate.

  13. In-situ calibration and certification of high dc voltage

    SciTech Connect

    Wickoff, B.

    1982-01-01

    A technical calibration service developed by an electrical standards laboratory to support a production facility in the calibration and certification of electron beam welder is described. The in-situ certification process utilizing standards traceable to NBS, documented procedures, applicable error analyses, and certified tolerances assigned to the calibration results are discussed.

  14. In situ strengths of matrix in a composite

    NASA Astrophysics Data System (ADS)

    Huang, Zheng-Ming; Xin, Li-Min

    2017-02-01

    A major obstacle to achieving reasonable strength prediction of a composite only from its constituent information is in the determination of in situ strengths of the matrix. One can measure only the original strengths of the pure matrix, on the basis of which the predicted transverse strengths of a unidirectional (UD) composite are far from reality. It is impossible to reliably measure matrix in situ strengths. This paper focuses on the correlation between in situ and original strengths. Stress concentrations in a matrix owing to the introduction of fibers are attributed to the strength variation. Once stress concentration factors (SCFs) are obtained, the matrix in situ strengths are assigned as the original counterparts divided by them. Such an SCF cannot be defined following a classical approach. All of the relevant issues associated with determining it are systematically addressed in this paper. Analytical expressions for SCFs under transverse tension, transverse compression, and transverse shear are derived. Closed-form and compact formulas for all of the uniaxial strengths of a UD composite are first presented in this paper. Their application to strength predictions of a number of typical UD composites demonstrates the correctness of these formulas.

  15. IN SITU Device for Real-Time Catalyst Deactivation Measurements

    SciTech Connect

    Fossil Energy Research

    2008-03-31

    SCR catalyst management has become an important operations and maintenance activity for coal-fired utility boilers in the United States. To facilitate this activity, a method to determine Catalyst Activity in situ is being developed. This report describes the methodology and presents the results of a two ozone season demonstration conducted at Alabama Power Company's Gorgas Unit 10 during the 2005 and 2006 ozone seasons. The results showed that the in situ measurements are in good agreement with the laboratory measurements and the technique has some advantages over the traditional laboratory method of determining Catalyst Activity and Reactor Potential. SCR Performance is determined by the overall Reactor Potential (the product of the Catalyst Activity and the available surface area per unit of flue gas). The in situ approach provides a direct measurement of Reactor Potential under actual operating conditions, whereas laboratory measurements of Catalyst Activity need to be coupled with estimates of catalyst pluggage and flue gas flowrate in order to assess Reactor Potential. The project also showed that the in situ activity results can easily be integrated into catalyst management software to aid in making informed catalyst decisions.

  16. Inhibition in the Limulus lateral eye in situ

    PubMed Central

    1978-01-01

    Inhibition in the Limulus lateral eye in situ is qualitatively similar to that in the excised eye. In both preparations ommatidia mutually inhibit one another, and the magnitude of the inhibitory effects are linear functions of the response rate of individual ommatidia. The strength of inhibition exerted between single ommatidia is also about the same for both preparations; however, stronger effects can converge on a single ommatidium in situ. At high levels of illumination of the retina in situ the inhibitory effects are often strong enough to produce sustained oscillations in the discharge of optic nerve fibers. The weaker inhibitory influences at low levels of illumination do not produce oscillations but decrease the variance of the optic nerve discharge. Thresholds for the inhibitory effects appear to be determined by both presynaptic and postsynaptic cellular processes. Our results are consistent with the idea that a single ommatidium can be inhibited by more of its neighbors in an eye in situ than in an excised eye. Leaving intact the blood supply to the eye appears to preserve the functional integrity of the retinal pathways which mediate inhibition. PMID:670927

  17. ENGINEERING ISSUE: IN SITU BIOREMEDIATION OF CONTAMINATED UNSATURATED SUBSURFACE SOILS

    EPA Science Inventory

    An emerging technology for the remediation of unsaturated subsurface soils involves the use of microorganisms to degrade contaminants which are present in such soils. Understanding the processes which drive in situ bioremediation, as well as the effectiveness and efficiency of th...

  18. Acral Lentiginous Melanoma in Situ: A Diagnostic and Management Challenge

    PubMed Central

    Park, Hyun Sun; Cho, Kwang Hyun

    2010-01-01

    Early stage recognition of acral lentiginous melanoma (ALM) is important for a better prognosis, but in-depth understanding and proper management of ALM in situ is complicated, because there are only a few reports, probably due to its rarity and diagnostic difficulty. We have reviewed our experience with seven patients who were diagnosed as having ALM in situ and discuss how to accurately diagnose and properly manage these rare lesions. Clinically the lesions showed black to brown discoloration of the nail with Hutchinson’s sign and hyperpigmented macules on the heel with color variegation. All the lesions showed a diffuse lentiginous pattern of melanocytic proliferation with variable level of atypism along the dermoepidermal junction. Dermoscopic findings were available in three and revealed parallel ridge patterns. Confrontation of clinical and histopathologic findings was observed in three, and the lesions were not recognized or diagnosed as ALM in situ in the first place. Excision of the primary lesion with variable operative margin was done as an initial treatment. Recurrence was observed in three patients and one developed invasive ALM and lymph node metastasis. Integration of all available information concerning the clinical presentation, histopathology, and dermoscopic findings is very important and can lead to the best classification for correct diagnosis. Lack of knowledge upon clinical course and optimal margin to control ALM in situ provokes the need for further studies with longer follow up and larger number of cases. PMID:24281086

  19. Intraoperative in situ radial artery conduit flow assessment.

    PubMed

    Canver, Charles C; Yousafzai, Sajjad M

    2008-01-01

    A technique is described for simple flow assessment of the in situ radial artery conduit during coronary bypass via a small incision. This technique allows morphologic and physiologic direct intraoperative assessment of radial artery quality and expands the use of radial artery during coronary artery surgery.

  20. In situ TEM electromechanical testing of nanowires and nanotubes.

    PubMed

    Espinosa, Horacio D; Bernal, Rodrigo A; Filleter, Tobin

    2012-11-05

    The emergence of one-dimensional nanostructures as fundamental constituents of advanced materials and next-generation electronic and electromechanical devices has increased the need for their atomic-scale characterization. Given its spatial and temporal resolution, coupled with analytical capabilities, transmission electron microscopy (TEM) has been the technique of choice in performing atomic structure and defect characterization. A number of approaches have been recently developed to combine these capabilities with in-situ mechanical deformation and electrical characterization in the emerging field of in-situ TEM electromechanical testing. This has enabled researchers to establish unambiguous synthesis-structure-property relations for one-dimensional nanostructures. In this article, the development and latest advances of several in-situ TEM techniques to carry out mechanical and electromechanical testing of nanowires and nanotubes are reviewed. Through discussion of specific examples, it is shown how the merging of several microsystems and TEM has led to significant insights into the behavior of nanowires and nanotubes, underscoring the significant role in-situ techniques play in the development of novel nanoscale systems and materials.

  1. DEMONSTRATION BULLETIN: IN-SITU VACUUM EXRACTION: TERRA VAC, INC.

    EPA Science Inventory

    This in-situ vacuum extraction technology is a process for the removal and venting of volatile organic compounds (VOCs) from the vadose or unsaturated zone of soils. Often, these compounds can be removed from the vadose zone before they have a chance to contaminate groundwater. ...

  2. Terra Vac In Situ Vacuum Extraction System: Applications Analysis Report

    EPA Science Inventory

    This document is an evaluation of the Terra Vac in situ vacuum extraction system and its applicability as a treatment method for waste site cleanup. This report analyzes the results from the Superfund Innovative Technology Evaluation (SITE) Program’s 56-day demonstration at t...

  3. FISH-ing for Genes: Modeling Fluorescence "in situ" Hybridization

    ERIC Educational Resources Information Center

    Baker, William P.; Jones, Carleton Buck

    2006-01-01

    Teaching methods of genetic analysis such as fluorescence in situ hybridization (FISH) can be an important part of instructional units in biology, microbiology, and biotechnology. Experience, however, indicates that these topics are difficult for many students. The authors of this article describe how they created an activity that effectively…

  4. Challenges in mobility and robotics for in-situ science

    NASA Technical Reports Server (NTRS)

    Wilcox, B.

    2002-01-01

    In-situ science on planetary surfaces such as Mars, Venus, Mercury and Titan pose extreme challenges for mobile robots. Future missions will involve surface, subsurface, and atmospheric mobility which focuses the need for technology development in sensing, autonomy, and mobile robot architectures for solar system exploration.

  5. Operability test report for the in SITU vapor sampling

    SciTech Connect

    Corbett, J.E., Westinghouse Hanford

    1996-05-31

    This report documents the successful completion of testing for the In Situ Vapor Sampling (ISVS) system. The report includes the test procedure (WHC-SD-WM-OTP-196, Rev OA), data sheets, exception resolutions, and a test report summary. This report conforms to the guidelines established in WHC-IP-1026, `Engineering Practice Guidelines,` Appendix L, `Operability Test Procedures and Reports.`

  6. Enhanced In Situ Bioremediation. Innovative Technology Summary Report

    SciTech Connect

    2002-03-01

    Enhanced In-Situ Bioremediation (ISB) provides increased degradation of contaminants in the subsurface by indigenous microorganisms present in the soil by manipulating this natural process. In addition, there is reduced worker risk, and decreased waste management costs associated with traditional pump and treat technology.

  7. IN-SITU FENTON OXIDATION: A CRITICAL ANALYSIS

    EPA Science Inventory

    In-situ Fenton oxidation (ISFO) is a rapidly emerging technology which involves the injection of hydrogen peroxide (H2O2) and other chemical reagents into the subsurface for the purpose of oxidizing and transforming contaminants. ISFO is being applied at an increasing number of ...

  8. IN-SITU CHEMICAL OXIDATION - DNAPL MASS REDUCTION TECHNOLOGY

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) is a rapidly developing technology used at hazardous waste sites where oxidants and complimentary reagents are injected into the subsurface to transform organic contaminants into less toxic byproducts. This technology is being used at new sites ...

  9. Alternative systems for in situ bioremediation: Enhanced control and contact

    SciTech Connect

    Burke, G.K.; Rhodes, D.K.

    1995-12-31

    Much of the past emphasis on biological degradation remediation has been placed on culturing or enhancing microbes to consume contaminants within a soil or water matrix, and site contaminant characterization. This emphasis has demonstrated that microbes are effective degraders for a variety of contaminants, and at most sites, contaminant-degrading microbes are present within the subsurface. For sites where microbes are present, they typically are inefficient for in situ remediation without the appropriate environmental conditions. In situ bioremediation tends to be governed by the ability to cost effectively and rapidly distribute oxygen, microbes, nutrients, and/or surfactants throughout the subsurface soils while simultaneously maintaining a controlled subsurface environment. Adapted equipment has been used to efficiently permeate or saturate the contaminated soils with a combination of oxygen source material, nutrients, surfactants and/or microbial cultures. These technologies, combined with oxygen delivery and control systems, enhance bioremediation as a viable alternative for in situ remediation. These same systems can deliver oxidation chemistry to pretreat the soils. The development and utilization of a number of in situ bioremediation technologies with a demonstrated ability to enhance contact and control within the contaminated subsoils are discussed, focusing on Bioventing, BioSparge{sup SM}, and Deep Soil Fracture BioInjection{trademark}.

  10. Bacterial Biotransformations for the In situ Stabilization of Plutonium

    SciTech Connect

    Neu, Mary; Boukhalfa, Hakim; Icopini, Gary; Hersman, Larry; Lack, Joe; Priester, John; Olson, Scott; Holden, Patricia

    2005-04-20

    Plutonium contamination in the environment is generally low-level and may be present and transported in a range of forms (IV, V, VI). Current remediation strategies are costly, financially and in terms of increased exposure risk to people and the environment. In situ bacterial biostabilization is a promising alternative.

  11. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect

    Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  12. In-situ mechanical testing during X-ray diffraction

    SciTech Connect

    Van Swygenhoven, Helena Van Petegem, Steven

    2013-04-15

    Deforming metals during recording X-ray diffraction patterns is a useful tool to get a deeper understanding of the coupling between microstructure and mechanical behaviour. With the advances in flux, detector speed and focussing techniques at synchrotron facilities, in-situ mechanical testing is now possible during powder diffraction and Laue diffraction. The basic principle is explained together with illustrative examples.

  13. Extraction of in situ cosmogenic 14C from olivine

    USGS Publications Warehouse

    Pigati, J.S.; Lifton, N.A.; Timothy, Jull A.J.; Quade, Jay

    2010-01-01

    Chemical pretreatment and extraction techniques have been developed previously to extract in situ cosmogenic radiocarbon (in situ 14C) from quartz and carbonate. These minerals can be found in most environments on Earth, but are usually absent from mafic terrains. To fill this gap, we conducted numerous experiments aimed at extracting in situ 14C from olivine ((Fe,Mg)2SiO4). We were able to extract a stable and reproducible in situ 14C component from olivine using stepped heating and a lithium metaborate (LiBO2) flux, following treatment with dilute HNO3 over a variety of experimental conditions. However, measured concentrations for samples from the Tabernacle Hill basalt flow (17.3 ?? 0.3 ka4) in central Utah and the McCarty's basalt flow (3.0 ?? 0.2 ka) in western New Mexico were significantly lower than expected based on exposure of olivine in our samples to cosmic rays at each site. The source of the discrepancy is not clear. We speculate that in situ 14C atoms may not have been released from Mg-rich crystal lattices (the olivine composition at both sites was ~Fo65Fa35). Alternatively, a portion of the 14C atoms released from the olivine grains may have become trapped in synthetic spinel-like minerals that were created in the olivine-flux mixture during the extraction process, or were simply retained in the mixture itself. Regardless, the magnitude of the discrepancy appears to be inversely proportional to the Fe/(Fe+Mg) ratio of the olivine separates. If we apply a simple correction factor based on the chemical composition of the separates, then corrected in situ 14C concentrations are similar to theoretical values at both sites. At this time, we do not know if this agreement is fortuitous or real. Future research should include measurement of in situ 14C concentrations in olivine from known-age basalt flows with different chemical compositions (i.e. more Fe-rich) to determine if this correction is robust for all olivine-bearing rocks. ?? 2010 by the Arizona

  14. Do we really need in-situ bioassays?

    SciTech Connect

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    In-situ bioassays are needed to validate the results from laboratory testing and to understand biological interactions. Standard laboratory protocols provide reproducible test results, and the precision of those tests can be mathematically defined. Significant correlations between toxic substances and levels of response (bioaccumulation and bioeffects) have also been demonstrated with natural field populations and suggest that the laboratory results can accurately predict field responses. An equal number of studies have shown a lack of correlation between laboratory bioassay results and responses of natural field populations. The best way to validate laboratory results is with manipulative field testing; i.e., in-situ bioassays with caged organisms. Bioaccumulation in transplanted bivalves has probably been the most frequently used form of an in-situ bioassay. The authors have refined those methods to include synoptic measurements of bioaccumulation and growth. Growth provides an easily-measured bioeffects endpoint and a means of calibrating bioaccumulation. Emphasis has been on minimizing the size range of test animals, repetitive measurements of individuals and standardization of test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Others have developed methods for in-situ bioassays using eggs, larvae, unicellular organisms, crustaceans, benthic invertebrates, bivalves, and fish. In the final analysis, the in-situ approach could be considered as an exposure system where any clinical measurements are possible. The most powerful approach would be to use the same species in laboratory and field experiments with the same endpoints.

  15. Additive manufacturing for in situ repair of osteochondral defects.

    PubMed

    Cohen, Daniel L; Lipton, Jeffrey I; Bonassar, Lawrence J; Lipson, Hod

    2010-09-01

    Tissue engineering holds great promise for injury repair and replacement of defective body parts. While a number of techniques exist for creating living biological constructs in vitro, none have been demonstrated for in situ repair. Using novel geometric feedback-based approaches and through development of appropriate printing-material combinations, we demonstrate the in situ repair of both chondral and osteochondral defects that mimic naturally occurring pathologies. A calf femur was mounted in a custom jig and held within a robocasting-based additive manufacturing (AM) system. Two defects were induced: one a cartilage-only representation of a grade IV chondral lesion and the other a two-material bone and cartilage fracture of the femoral condyle. Alginate hydrogel was used for the repair of cartilage; a novel formulation of demineralized bone matrix was used for bone repair. Repair prints for both defects had mean surface errors less than 0.1 mm. For the chondral defect, 42.8+/-2.6% of the surface points had errors that were within a clinically acceptable error range; however, with 1 mm path planning shift, an estimated approximately 75% of surface points could likely fall within the benchmark envelope. For the osteochondral defect, 83.6+/-2.7% of surface points had errors that were within clinically acceptable limits. In addition to implications for minimally invasive AM-based clinical treatments, these proof-of-concept prints are some of the only in situ demonstrations to-date, wherein the substrate geometry was unknown a priori. The work presented herein demonstrates in situ AM, suggests potential biomedical applications and also explores in situ-specific issues, including geometric feedback, material selection and novel path planning techniques.

  16. Clinical factors associated with subclinical spread of in situ melanoma.

    PubMed

    Shin, Thuzar M; Etzkorn, Jeremy R; Sobanko, Joseph F; Margolis, David J; Gelfand, Joel M; Chu, Emily Y; Elenitsas, Rosalie; Shaikh, Waqas R; Miller, Christopher J

    2017-04-01

    Subclinical spread of in situ melanoma occurs at a wide frequency, ranging from 12% to 71%. To identify clinical factors associated with subclinical spread of in situ melanoma. We used a retrospective, cross-sectional study of 674 consecutive in situ melanomas to examine 627 patients treated with Mohs surgery and melanoma antigen recognized by T cells 1 immunostaining. The presence of subclinical spread was correlated with clinical characteristics. Univariate and multivariate logistic regression analyses were performed to generate odds ratios (ORs) and 95% confidence intervals (CIs). Both univariate and multivariate analyses demonstrated significantly increased odds for subclinical spread of in situ melanomas when they were located on the head or neck, at acral sites, or on the pretibial leg (OR 1.97, 95% CI 1.41-3.40); in persons with a history of prior treatment (OR 2.77, 95% CI 1.74-4.420); melanomas of preoperative size >1 cm (OR 1.74, 95% CI 1.23-2.46, P = .002); or in persons ≥60 years old (OR 1.47, 95% CI 1.01-2.13, P = .042). A count prediction model demonstrated that the risk for subclinical spread increased with the number of clinical risk factors. We used a single-site, retrospective study design. Clarifying the risk factors for subclinical spread might help to refine triage of in situ melanomas to the appropriate surgical techniques for margin assessment prior to reconstruction. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  17. Long-distance Dating: In situ geochronology for planetary missions

    NASA Astrophysics Data System (ADS)

    Cho, Y.; Cohen, B. A.

    2016-12-01

    Isotopic dating is an essential tool to establish an absolute chronology for geological events. It enables a planet's crystallization history, magmatic evolution, and alteration to be placed into the framework of solar system history. The capability for in situ geochronology will open up the ability for this crucial measurement to be accomplished as part of lander or rover complement. An in situ geochronology package can also complement sample return missions by identifying the most interesting rocks to cache or return to Earth. The capability of flight instruments to conduct in situ geochronology is called out in the NASA Planetary Science Decadal Survey and the NASA Technology Roadmap as needing development to serve the community's needs. Beagle 2 is the only mission launched to date with the explicit aim to perform in situ K-Ar isotopic dating [1], but it failed to communicate and was lost. The first in situ K-Ar date on Mars, using SAM and APXS measurements on the Cumberland mudstone [2], yielded an age of 4.21 ± 0.35 Ga and validated the idea of K-Ar dating on other planets, though the Curiosity method is not purpose-built for dating and requires many assumptions that degrade its precision. To get more precise and meaningful ages, multiple groups are developing dedicated in situ dating instruments [3-7], including the K-Ar Laser Experiment (KArLE) [5]. KArLE ablates a rock sample, measures K using laser-induced breakdown spectroscopy (LIBS), measures liberated Ar using mass spectrometry (MS), and relates the two by measuring the volume of the ablated pit with optical imaging. The KArLE breadboard tested planetary analog samples yielding ages with 25% uncertainty on very young samples (<50Ma) and 10% uncertainties on older samples. [1] Talboys, et al. (2009) Planetary and Space Science 57, 1237-1245, doi:10.1016/j.pss.2009.02.012. [2] Farley, et al. (2014) Science 343, doi:10.1126/science.1247166. [3] Anderson, et al. (2015) Rapid Comm. Mass Spec. 29, 191

  18. From in vitro to in situ tissue engineering.

    PubMed

    Sengupta, Debanti; Waldman, Stephen D; Li, Song

    2014-07-01

    In vitro tissue engineering enables the fabrication of functional tissues for tissue replacement. In addition, it allows us to build useful physiological and pathological models for mechanistic studies. However, the translation of in vitro tissue engineering into clinical therapies presents a number of technical and regulatory challenges. It is possible to circumvent the complexity of developing functional tissues in vitro by taking an in situ tissue engineering approach that uses the body as a native bioreactor to regenerate tissues. This approach harnesses the innate regenerative potential of the body and directs the appropriate cells to the site of injury. This review surveys the biomaterial-, cell-, and chemical factor-based strategies to engineer tissue in vitro and in situ.

  19. In situ sensors for measurements in the global trosposphere

    NASA Technical Reports Server (NTRS)

    Saeger, M. L.; Eaton, W. C.; Wright, R. S.; White, J. H.; Tommerdahl, J. B.

    1981-01-01

    Current techniques available for the in situ measurement of ambient trace gas species, particulate composition, and particulate size distribution are reviewed. The operational specifications of the various techniques are described. Most of the techniques described are those that have been used in airborne applications or show promise of being adaptable to airborne applications. Some of the instruments described are specialty items that are not commercially-available. In situ measurement techniques for several meteorological parameters important in the study of the distribution and transport of ambient air pollutants are discussed. Some remote measurement techniques for meteorological parameters are also discussed. State-of-the-art measurement capabilities are compared with a list of capabilities and specifications desired by NASA for ambient measurements in the global troposphere.

  20. In-Situ Diffraction on the National Ignition Facility (NIF)

    NASA Astrophysics Data System (ADS)

    Eggert, Jon; Braun, Dave; Rygg, Ryan; Lazicki, Amy; Fratanduono, Dayne; Smith, Ray; Coppari, Federica; Kraus, Rick; Swift, Damian; McNaney, Jim; Ping, Yuan; Blobaum, Kerri; Wilson, Mike; Ahmed, Marium; Collins, Gilbert; Arsenlis, Tom; LLNL-Shock Physics Group Team

    2015-06-01

    Ramp compression experiments have opened a path toward the measurement of extreme states of compression for solid-state materials on lasers, pulsed power, and gas guns. While most experiments have measured wave profiles as an integrated probe of the material state, there is a trend toward making direct measurements of the material state in situ using diffraction, phase-contrast imaging, EXAFS, and XANES. This past year we succeeded in obtaining high-quality diffraction on the NIF using the TARget Diffraction In Situ (TARDIS) diagnostic. I will present some of our NIF results on lead and tantalum, including the prospects for determining not only structure, density, and stress, but also temperature and grain size in these experiments. I will close with future plans for further improving TARDIS.

  1. Evaluation of in-situ deformation experiments of TRIP steel

    NASA Astrophysics Data System (ADS)

    Procházka, J.; Kučerová, L.; Bystrianský, M.

    2017-02-01

    The paper reports on the behaviour of low alloyed TRIP (transformation induced plasticity) steel with Niobium during tensile test. The structures were analysed using in-situ tensile testing coupled with electron backscattering diffraction (EBSD) analysis carried out in scanning electron microscope (SEM). Steel specimens were of same chemical composition; however three different annealing temperatures, 800 °C, 850 °C and 950 °C, were applied to the material during the heat treatment. The treatment consisted of annealing for 20 minutes in the furnace; cooling in salt bath after the heating and holding at 425 °C for 20 minutes for all the samples. Untreated bar was used as reference material. Flat samples for deformation stage were cut out of the heat-treated bars. In situ documentation of microstructure and crystallography development were carried out during the deformation experiments. High deformation lead to significant degradation of EBSD signal.

  2. In situ ingestion of microfibres by meiofauna from sandy beaches.

    PubMed

    Gusmão, Felipe; Domenico, Maikon Di; Amaral, A Cecilia Z; Martínez, Alejandro; Gonzalez, Brett C; Worsaae, Katrine; Ivar do Sul, Juliana A; Cunha Lana, Paulo da

    2016-09-01

    Microfibres are widespread contaminants in marine environments across the globe. Detecting in situ ingestion of microfibres by small marine organisms is necessary to understand their potential accumulation in marine food webs and their role in marine pollution. We have examined the gut contents of meiofauna from six sandy beaches in the Atlantic Ocean and the Mediterranean. Out of twenty taxonomic groups, three species of the common sandy beach annelid Saccocirrus displayed in situ ingestion of microfibres in all sites. Laboratory observations showed that species of Saccocirrus are able to egest microfibres with no obvious physical injury. We suggest that their non-selective microphagous suspension-feeding behaviour makes Saccocirrus more prone to ingest microfibres. Although microfibres are rapidly egested with no apparent harm, there is still the potential for trophic transfer into marine food webs through predation of Saccocirrus.

  3. In situ X-ray-based imaging of nano materials

    DOE PAGES

    Weker, Johanna Nelson; Huang, Xiaojing; Toney, Michael F.

    2016-02-13

    We study functional nanomaterials that are heterogeneous and understanding their behavior during synthesis and operation requires high resolution diagnostic imaging tools that can be used in situ. Over the past decade, huge progress has been made in the development of X-ray based imaging, including full field and scanning microscopy and their analogs in coherent diffractive imaging. Currently, spatial resolution of about 10 nm and time resolution of sub-seconds are achievable. For catalysis, X-ray imaging allows tracking of particle chemistry under reaction conditions. In energy storage, in situ X-ray imaging of electrode particles is providing important insight into degradation processes. Recently,more » both spatial and temporal resolutions are improving to a few nm and milliseconds and these developments will open up unprecedented opportunities.« less

  4. In situ remediation technologies for mercury-contaminated soil

    DOE PAGES

    He, Feng; Gao, Jie; Pierce, Eric; ...

    2015-04-09

    A pollutant that poses significant risks to humans and the environment is mercury from anthropogenic activities. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. Our paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic,more » and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. We also discussed two emerging technologies, phytoremediation and nanotechnology, in this review.« less

  5. In situ remediation technologies for mercury-contaminated soil

    SciTech Connect

    He, Feng; Gao, Jie; Pierce, Eric; Strong, P. J.; Wang, Hailong; Liang, Liyuan

    2015-04-09

    A pollutant that poses significant risks to humans and the environment is mercury from anthropogenic activities. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. Our paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic, and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. We also discussed two emerging technologies, phytoremediation and nanotechnology, in this review.

  6. In situ bioremediation of petroleum hydrocarbon and other organic compounds

    SciTech Connect

    Alleman, B.C.; Leeson, A.

    1999-10-01

    From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Moreover, the world`s rivers, estuaries, and oceans are threatened by contamination from petroleum leaks and spills. Fortunately, most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. Good progress is being made in terms of developing innovative, cost-effective in situ approaches to bioremediation. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, cometabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

  7. OpenMC In Situ Source Convergence Detection

    SciTech Connect

    Aldrich, Garrett Allen; Dutta, Soumya; Woodring, Jonathan Lee

    2016-05-07

    We designed and implemented an in situ version of particle source convergence for the OpenMC particle transport simulator. OpenMC is a Monte Carlo based-particle simulator for neutron criticality calculations. For the transport simulation to be accurate, source particles must converge on a spatial distribution. Typically, convergence is obtained by iterating the simulation by a user-settable, fixed number of steps, and it is assumed that convergence is achieved. We instead implement a method to detect convergence, using the stochastic oscillator for identifying convergence of source particles based on their accumulated Shannon Entropy. Using our in situ convergence detection, we are able to detect and begin tallying results for the full simulation once the proper source distribution has been confirmed. Our method ensures that the simulation is not started too early, by a user setting too optimistic parameters, or too late, by setting too conservative a parameter.

  8. Raman spectroscopy for in-situ monitoring of electrode processes

    SciTech Connect

    Varma, R; Cook, G M; Yao, N P

    1982-04-01

    The theoretical and experimental applications of Raman spectroscopic techniques to the study of battery electrode processes are described. In particular, the potential of Raman spectroscopy as an in-situ analytical tool for the characterization of the structure and composition of electrode surface layers at electrode-electrolyte interfaces during electrolysis is examined. It is anticipated that this understanding of the battery electrode processes will be helpful in designing battery active material with improved performance. The applications of Raman spectroscopy to the in-situ study of electrode processes has been demonstrated in a few selected areas, including: (1) the anodic corrosion of lead in sulfuric acid and (2) the anodization and sulfation of tetrabasicleadsulfate in sulfuric acid. Preliminary results on the anodization of iron and on the electrochemical behavior of nickel positive-electrode active material in potassium hydroxide electrolytes are presented in the Appendix.

  9. Underwater microscopy for in situ studies of benthic ecosystems

    NASA Astrophysics Data System (ADS)

    Mullen, Andrew D.; Treibitz, Tali; Roberts, Paul L. D.; Kelly, Emily L. A.; Horwitz, Rael; Smith, Jennifer E.; Jaffe, Jules S.

    2016-07-01

    Microscopic-scale processes significantly influence benthic marine ecosystems such as coral reefs and kelp forests. Due to the ocean's complex and dynamic nature, it is most informative to study these processes in the natural environment yet it is inherently difficult. Here we present a system capable of non-invasively imaging seafloor environments and organisms in situ at nearly micrometre resolution. We overcome the challenges of underwater microscopy through the use of a long working distance microscopic objective, an electrically tunable lens and focused reflectance illumination. The diver-deployed instrument permits studies of both spatial and temporal processes such as the algal colonization and overgrowth of bleaching corals, as well as coral polyp behaviour and interspecific competition. By enabling in situ observations at previously unattainable scales, this instrument can provide important new insights into micro-scale processes in benthic ecosystems that shape observed patterns at much larger scales.

  10. Underwater microscopy for in situ studies of benthic ecosystems

    PubMed Central

    Mullen, Andrew D.; Treibitz, Tali; Roberts, Paul L. D.; Kelly, Emily L. A.; Horwitz, Rael; Smith, Jennifer E.; Jaffe, Jules S.

    2016-01-01

    Microscopic-scale processes significantly influence benthic marine ecosystems such as coral reefs and kelp forests. Due to the ocean's complex and dynamic nature, it is most informative to study these processes in the natural environment yet it is inherently difficult. Here we present a system capable of non-invasively imaging seafloor environments and organisms in situ at nearly micrometre resolution. We overcome the challenges of underwater microscopy through the use of a long working distance microscopic objective, an electrically tunable lens and focused reflectance illumination. The diver-deployed instrument permits studies of both spatial and temporal processes such as the algal colonization and overgrowth of bleaching corals, as well as coral polyp behaviour and interspecific competition. By enabling in situ observations at previously unattainable scales, this instrument can provide important new insights into micro-scale processes in benthic ecosystems that shape observed patterns at much larger scales. PMID:27403715

  11. In Situ Measurement And Remote Sensing Of Gaseous Atmosphere

    NASA Astrophysics Data System (ADS)

    Rippel, Harald

    1989-12-01

    The newly developed Double Pendulum Interferometer (DPI) with its unique optical design provides the possibility of remote and in situ measurements of exhaust gases in smoke-stacks. The remote configuration is presented in fig. 1. Due to its design the DPI guarantees for - high short and long term stability - insensitivity to external vibration and temperature changes (Ref. 1). The instrument not only identifies the type of gas but also allows a quantitative measurement of gas concentrations (Ref. 2). Fig. 2 gives the computed emission for a high temperature smoke-stack (HF, H20, CO2, and 02) for an in situ configuration. Reg. 1. Jaacks, R. G. and Rippel, H., Double Pendulum Michelson Interferometer with Extended Spectral Resolution, Appl. Opt., Vol. 27, 1988 2. Rippel, H., Quantitative Analysis Software for KT FTIR Instruments, Kayser-Threde, Technical Note, 1988

  12. Application of Genomic In Situ Hybridization in Horticultural Science

    PubMed Central

    Ramzan, Fahad; Lim, Ki-Byung

    2017-01-01

    Molecular cytogenetic techniques, such as in situ hybridization methods, are admirable tools to analyze the genomic structure and function, chromosome constituents, recombination patterns, alien gene introgression, genome evolution, aneuploidy, and polyploidy and also genome constitution visualization and chromosome discrimination from different genomes in allopolyploids of various horticultural crops. Using GISH advancement as multicolor detection is a significant approach to analyze the small and numerous chromosomes in fruit species, for example, Diospyros hybrids. This analytical technique has proved to be the most exact and effective way for hybrid status confirmation and helps remarkably to distinguish donor parental genomes in hybrids such as Clivia, Rhododendron, and Lycoris ornamental hybrids. The genome characterization facilitates in hybrid selection having potential desirable characteristics during the early hybridization breeding, as this technique expedites to detect introgressed sequence chromosomes. This review study epitomizes applications and advancements of genomic in situ hybridization (GISH) techniques in horticultural plants. PMID:28459054

  13. In situ-Gelling, Erodible N-Isopropylacrylamide Copolymers

    PubMed Central

    Lee, Bae Hoon; Vernon, Brent

    2005-01-01

    Summary Copolymers of N-isopropylacrylamide, 2-hydroxyethyl methacryl lactate and acrylic acid were prepared with varying mole ratios of monomers to develop copolymers with gelation properties above a certain concentration for a bioerodible, in-situ gelling material. The copolymers formed gels in situ under physiological condition. The gelation temperature of the copolymers decreased as the HEMA-lactate content of the copolymers increased due to the hydrophobicity of HEMA-lactate, and increased as the AAc content increased due to the hydrophilicity of AAc. The gels redissolve at 37 °C as their LCSTs increase above 37°C due to the hydrolysis of the HEMA-lactate pendant groups. PMID:15997439

  14. Detection of prokaryotic cells with fluorescence in situ hybridization.

    PubMed

    Zwirglmaier, Katrin

    2010-01-01

    Fluorescence in situ hybridization with rRNA targeted oligonucleotide probes is nowadays one of the core techniques in microbial ecology, allowing the identification and quantification of microbial cells in environmental samples in situ. Next to the classic FISH protocol, which uses fluorescently monolabelled probes, the more sensitive CARD-FISH (also known as TSA-FISH), which involves an enzyme catalyzed signal amplification step, is becoming increasingly popular. This chapter describes protocols for both methods. While classic FISH has the advantage of being relatively cheap and easy to do on morphologically diverse samples, CARD-FISH offers a significantly higher sensitivity, allowing the detection of slow growing or metabolically inactive cells, which are below the detection limit of classic FISH. The drawback here is the considerably higher price for the probes and advanced cell fixation and permeabilization requirements that have to be optimized for different target cells.

  15. Final report: In situ radio frequency heating demonstration

    SciTech Connect

    Jarosch, T.R.; Beleski, R.J.; Faust, D.

    1994-01-05

    A field demonstration of in situ radio frequency heating was performed at the Savannah River Site (SRS) as part of the US Department of Energy-Office of Technology Development`s Integrated Demonstration. The objective of the demonstration was to investigate the effectiveness of in situ radio frequency (RF) heating as an enhancement to vacuum extraction of residual solvents (primarily trichloroethylene and perchloroethylene) held in vadose zone clay deposits. Conventional soil vacuum extraction techniques are mass transfer limited because of the low permeabilities of the clays. By selectively heating the clays to temperatures at or above 100{degrees}C, the release or transport of the solvent vapors will be enhanced as a result of several factors including an increase in the contaminant vapor pressure and diffusivity and an increase in the effective permeability of the formation with the release of water vapor.

  16. In Situ Vesicle Formation by Native Chemical Ligation

    PubMed Central

    Brea, Roberto J.; Cole, Christian M.

    2015-01-01

    Phospholipid vesicles are of intense fundamental and practical interest, yet methods for their de novo generation from reactive precursors are limited. A non-enzymatic and chemoselective method to spontaneously generate phospholipid membranes from water-soluble starting materials would be a powerful tool for generating vesicles and studying lipid membranes. Here we describe the use of native chemical ligation (NCL) to rapidly prepare phospholipids spontaneously from thioesters. While NCL is one of the most popular tools for synthesizing proteins and nucleic acids, to our knowledge this is the first example of using NCL to generate phospholipids de novo. The lipids are capable of in situ synthesis and self-assembly into vesicles that can grow to several microns in diameter. The selectivity of the NCL reaction enables compatibility of in situ membrane formation with biological materials such as proteins. This work expands the application of NCL to the formation of phospholipid membranes. PMID:25346090

  17. In situ NiTi/Nb(Ti) composite

    SciTech Connect

    Jiang, Daqiang Cui, Lishan; Jiang, Jiang; Zheng, Yanjun

    2013-12-15

    Graphical abstract: - Highlights: • In situ NiTi/Nb(Ti) composites were fabricated. • The transformation temperature was affected by the mixing Ti:Ni atomic ratios. • The NiTi component became micron-scale lamella after forging and rolling. • The composite exhibited high strength and high damping capacity. - Abstract: This paper reports on the creation of a series of in situ NiTi/Nb(Ti) composites with controllable transformation temperatures based on the pseudo-binary hypereutectic transformation of NiTi–Nb system. The composite constituent morphology was controlled by forging and rolling. It is found that the thickness of the NiTi lamella in the composite reached micron level after the hot-forging and cold-rolling. The NiTi/Nb(Ti) composite exhibited high damping capacity as well as high yield strength.

  18. In situ remediation technologies for mercury-contaminated soil.

    PubMed

    He, Feng; Gao, Jie; Pierce, Eric; Strong, P J; Wang, Hailong; Liang, Liyuan

    2015-06-01

    Mercury from anthropogenic activities is a pollutant that poses significant risks to humans and the environment. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. This paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic, and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. Two emerging technologies, phytoremediation and nanotechnology, are also discussed in this review.

  19. In Situ Instrumentation for Sub-Surface Planetary Geochemistry

    NASA Technical Reports Server (NTRS)

    Bodnarik, J.; Evans, L.; Floyd, S.; Lim, L.; McClanahan, T.; Namkung, M.; Parsons, A.; Schweitzer, J.; Starr, R.; Trombka, J.

    2010-01-01

    Novel instrumentation is under development at NASA's Goddard Space Flight Center, building upon earth-based techniques for hostile environments, to infer geochemical processes important to formation and evolution of solid bodies in our Solar System. A prototype instrument, the Pulsed Neutron Generator Gamma Ray and Neutron Detectors (PNG-GRAND), has a 14 MeV pulsed neutron generator coupled with gamma ray and neutron detectors to measure quantitative elemental concentrations and bulk densities of a number of major, minor and trace elements at or below the surfaces with approximately a meter-sized spatial resolution down to depths of about 50 cm without the need to drill. PNG-GRAND's in situ a meter-scale measurements and adaptability to a variety of extreme space environments will complement orbital kilometer-scale and in-situ millimeter scale elemental and mineralogical measurements to provide a more complete picture of the geochemistry of planets, moons, asteroids and comets.

  20. In-situ cure monitoring of advanced composite materials

    NASA Astrophysics Data System (ADS)

    Saliba, Tony; Saliba, Susan; Lanzafame, John; Gudeman, Linda

    Automatic process control and optimization depends on the ability to effectively determine the state of the process. In-situ sensors capable of monitoring the physical and chemical changes are therefore essential. The use of an in-situ acoustic ultrasonic sensor to monitor the cure characteristics of Bismaleimides (BMI) based composite materials was investigated. The acoustic attenuation reflects changes in the viscosity of the resin. The effects on the acoustic response curve of laminate thickness, ply orientation as well as the type of BMI were studied. A general correlation relating the acoustic attenuation of a curing BMI composite to the actual viscosity was developed. The results obtained for BMI were compared to those obtained from epoxy based composite materials.

  1. Axillary node dissection in ductal carcinoma in situ.

    PubMed

    Parker, R G; Berkbigler, D; Rees, K; Leung, K M; Legorreta, A P

    1998-04-01

    Intraductal carcinoma of the breast has become a well-defined entity that has been more frequently diagnosed since the introduction of mammography. For many years, the usual treatment has been mastectomy, often with axillary lymph node dissection. Concurrent with documentation that breast conservation treatment has been effective for many invasive breast cancers, such treatment has been introduced for noninvasive breast cancers (ductal carcinoma in situ and lobular cancer in situ). However, there is no basis for axillary dissection because tumor cells are contained by the basement membrane and should not metastasize. In this study, 107 axillary dissections were carried out, with an average of 20 nodes identified, and a single metastasis was identified.

  2. In situ protein folding and activation in bacterial inclusion bodies.

    PubMed

    Gonzalez-Montalban, Nuria; Natalello, Antonino; García-Fruitós, Elena; Villaverde, Antonio; Doglia, Silvia Maria

    2008-07-01

    Recent observations indicate that bacterial inclusion bodies formed in absence of the main chaperone DnaK result largely enriched in functional, properly folded recombinant proteins. Unfortunately, the molecular basis of this intriguing fact, with obvious biotechnological interest, remains unsolved. We have explored here two non-excluding physiological mechanisms that could account for this observation, namely selective removal of inactive polypeptides from inclusion bodies or in situ functional activation of the embedded proteins. By combining structural and functional analysis, we have not observed any preferential selection of inactive and misfolded protein species by the dissagregating machinery during inclusion body disintegration. Instead, our data strongly support that folding intermediates aggregated as inclusion bodies could complete their natural folding process once deposited in protein clusters, which conduces to significant functional activation. In addition, in situ folding and protein activation in inclusion bodies is negatively regulated by the chaperone DnaK.

  3. Stabilizing in situ oil shale retorts with injected grout

    NASA Astrophysics Data System (ADS)

    1980-03-01

    A retort grouting process has been developed which would solve certain problems associated with in situ recovery of crude oil by retorting oil shale, such as surface subsidence, disturbance of groundwater flow, and accumulation of spent shale at the surface. Essentially, the process consists of using the spent shale to make a grout that can be injected into the retort after processing is completed. Bench-scale experiments using a high-temperature process show that grout can be prepared with sufficient strength, mobility, and permeability to stabilize processed in situ oil shale retorts. By reducing the need for surface disposal of spent shale and by increasing the quantity of shale that can be retorted in a given area, the grouting method should significantly improve the economics of the oil recovery process while also offering environmental advantages over surface processing of the shale.

  4. In situ bioremediation of surface waters by periphytons.

    PubMed

    Wu, Yonghong; Xia, Lizhong; Yu, Zhiqiang; Shabbir, Sadaf; Kerr, Philip G

    2014-01-01

    Environmentally benign and sustainable biomeasures have become attractive options for the in situ remediation of polluted surface waters. In this paper, we review the current state of reported experiments utilizing naturally occurring periphyton. These are microbial communities consisting of heterotrophic and photoautotrophic microorganisms that are reportedly capable of remediating surface waters which suffer from pollution due to a variety of contaminants. In our review, we focus on four aspects of bioremediation: multiple contaminant removal, the processes involved in contaminant removal, successful cell immobilization technologies and finally, the consideration of safety in aquaculture. It has been noted that recent developments in immobilization technologies offer a fresh approach facilitating the application of periphyton. The use of periphyton biofilm overcomes several disadvantages of single species microbial aggregates. The inclusion of periphyton, as a stable micro-ecosystem, is a promising in situ strategy to restore decimated surface water ecosystems.

  5. First use of in situ vitrification on radioactive wastes

    SciTech Connect

    Bowlds, L.

    1992-03-01

    A high-temperature method for containing hazardous wastes, which was first developed in the 1980s, is being adapted for the in situ treatment of buried radioactive wastes by the US DOE's Idaho National Engineering Laboratory (INEL), following its recent report on successful preliminary tests. The method, called in situ vitrification (ISV), is an electrically induced thermal process that melts and fuses soil and wastes into a glass-like material at least as strong as natural obsidian or granite. Gases released during the process are captured and treated by an off-gas treatment system. After the wastes are vitrified, they could be left in place, or the mass could be broken up and transported to a disposal site. The glass-like substance would be chemically and physically similar to obsidian and from 4 to 10 times more durable than typical borosilicate glasses used to immobolize high-level nuclear wastes.

  6. In situ synchrotron x-ray photon beam characterization

    SciTech Connect

    Kyele, Nicholas R.; Silfhout, Roelof G. van; Manolopoulos, Spyros; Nikitenko, S.

    2007-03-15

    We have investigated two in situ methods of measuring x-ray beam parameters such as integrated intensity, position, and intensity distribution. These virtually transparent methods both rely on the collection of scattered radiation from a thin amorphous foil. The scattered radiation is collected by an active pixel sensor placed below the foil, well out of the direction of the beam path. These methods measure a cross-sectional image of the beam as opposed to a profile or beam centroid position provided by existing in situ detection methods. We present the results of measurements taken at a third generation synchrotron radiation source and provide analytical methods of deriving beam profile, position, and absolute intensity.

  7. In situ electrochemical dilatometry of carbide-derived carbons

    SciTech Connect

    Hantel, M M; Presser, Volker; Gogotsi, Yury

    2011-01-01

    The long life durability and extraordinary stability of supercapacitors are ascribed to the common concept that the charge storage is purely based on double-layer charging. Therefore the ideal supercapacitor electrode should be free of charge induced microscopic structural changes. However, recent in-situ investigations on different carbon materials for supercapacitor electrodes have shown that the charge and discharge is accompanied by dimensional changes of the electrode up to several percent. This work studies the influence of the pore size on the expansion behavior of carbon electrodes derived from titanium carbide-derived carbons with an average pore size between 5 and 8 Using tetraethylammonium tetrafluoroborate in acetonitrile, the swelling of the electrodes was measured by in situ dilatometry. The experiments revealed an increased expansion on the negatively charged electrode for pores below 6 , which could be described with pore swelling.

  8. An in situ assay for determination of benzodiazepine binding.

    PubMed

    Sher, P K; Schrier, B K; Van Putten, D

    1982-01-01

    Benzodiazepine (BDZ) receptors have been demonstrated recently in a variety of mammalian tissues. However, assay methods for such receptors have required that disrupted tissues be used. We have developed an in situ assay for this receptor utilizing intact cells cultured from the cerebral cortices of fetal mice which is more sensitive and physiologic than those used previously. Results obtained with this assay differ in the following ways from those in which disrupted tissues are used: (1) total and specific BDZ binding was as much as 10-fold higher in the in situ assays; (2) Scatchard analysis of the binding data is consistently nonlinear, revealing at least two binding sites with KD values of 5.5 and 303 nM, and (3) presumed nonneuronal receptors were found in abundance.

  9. In situ Gas Conditioning in Fuel Reforming for Hydrogen Generation

    SciTech Connect

    Bandi, A.; Specht, M.; Sichler, P.; Nicoloso, N.

    2002-09-20

    The production of hydrogen for fuel cell applications requires cost and energy efficient technologies. The Absorption Enhanced Reforming (AER), developed at ZSW with industrial partners, is aimed to simplify the process by using a high temperature in situ CO2 absorption. The in situ CO2 removal results in shifting the steam reforming reaction equilibrium towards increased hydrogen concentration (up to 95 vol%). The key part of the process is the high temperature CO2 absorbent. In this contribution results of Thermal Gravimetric Analysis (TGA) investigations on natural minerals, dolomites, silicates and synthetic absorbent materials in regard of their CO2 absorption capacity and absorption/desorption cyclic stability are presented and discussed. It has been found that the inert parts of the absorbent materials have a structure stabilizing effect, leading to an improved cyclic stability of the materials.

  10. In Situ Fabrication Technologies: Meeting the Challenge for Exploration

    NASA Technical Reports Server (NTRS)

    Howard, Richard W.

    2005-01-01

    A viewgraph presentation on Lunar and Martian in situ fabrication technologies meeting the challenges for exploration is shown. The topics include: 1) Exploration Vision; 2) Vision Requirements Early in the Program; 3) Vision Requirements Today; 4) Why is ISFR Technology Needed? 5) ISFR and In Situ Resource Utilization (ISRU); 6) Fabrication Feedstock Considerations; 7) Planetary Resource Primer; 8) Average Chemical Element Abundances in Lunar Soil; 9) Chemical Elements in Aerospace Engineering Materials; 10) Schematic of Raw Regolith Processing into Constituent Components; 11) Iron, Aluminum, and Basalt Processing from Separated Elements and Compounds; 12) Space Power Systems; 13) Power Source Applicability; 14) Fabrication Systems Technologies; 15) Repair and Nondestructive Evaluation (NDE); and 16) Habitat Structures. A development overview of Lunar and Martian repair and nondestructive evaluation is also presented.

  11. Methods and systems for in-situ electroplating of electrodes

    DOEpatents

    Zappi, Guillermo Daniel; Zarnoch, Kenneth Paul; Huntley, Christian Andrew; Swalla, Dana Ray

    2015-06-02

    The present techniques provide electrochemical devices having enhanced electrodes with surfaces that facilitate operation, such as by formation of a porous nickel layer on an operative surface, particularly of the cathode. The porous metal layer increases the surface area of the electrode, which may result in increasing the efficiency of the electrochemical devices. The formation of the porous metal layer is performed in situ, that is, after the assembly of the electrodes into an electrochemical device. The in situ process offers a number of advantages, including the ability to protect the porous metal layer on the electrode surface from damage during assembly of the electrochemical device. The enhanced electrode and the method for its processing may be used in any number of electrochemical devices, and is particularly well suited for electrodes in an electrolyzer useful for splitting water into hydrogen and oxygen.

  12. Long-term results of in situ subtalar arthrodesis

    PubMed Central

    Harisboure, Alain; Ohl, Xavier; Dehoux, Emile

    2010-01-01

    Isolated subtalar disorders often require subtalar arthrodesis. In this retrospective study of 28 in situ subtalar arthrodeses reviewed with a median follow-up of 56 months (range, 20–115), the authors attempted to detail the outcomes of in situ subtalar fusion, the consequences on adjacent joints and to determine clinical or radiological factors of failure. Clinical evaluation was realised with the AOFAS (American Orthopaedic Foot and Ankle Society) ankle hindfoot score. Radiographic evaluation included assessment of hindfoot alignment, subtalar fusion and arthritic evolution in the adjacent joints. The median functional score was 76.5/94 (range, 36–94). All 28 arthrodeses achieved union. Mild arthritic changes occurred in 43–65% in the different adjacent joints. These changes were not symptomatic. Varus malunion and clinical nonunion seem to be the most important causes of failure. PMID:20556382

  13. Long-term results of in situ subtalar arthrodesis.

    PubMed

    Joveniaux, Pierre; Harisboure, Alain; Ohl, Xavier; Dehoux, Emile

    2010-12-01

    Isolated subtalar disorders often require subtalar arthrodesis. In this retrospective study of 28 in situ subtalar arthrodeses reviewed with a median follow-up of 56 months (range, 20-115), the authors attempted to detail the outcomes of in situ subtalar fusion, the consequences on adjacent joints and to determine clinical or radiological factors of failure. Clinical evaluation was realised with the AOFAS (American Orthopaedic Foot and Ankle Society) ankle hindfoot score. Radiographic evaluation included assessment of hindfoot alignment, subtalar fusion and arthritic evolution in the adjacent joints. The median functional score was 76.5/94 (range, 36-94). All 28 arthrodeses achieved union. Mild arthritic changes occurred in 43-65% in the different adjacent joints. These changes were not symptomatic. Varus malunion and clinical nonunion seem to be the most important causes of failure.

  14. In-situ MHD energy conversion for fusion. [R

    SciTech Connect

    Campbell, R.B.; Logan, B.G.; Hoffman, M.A.

    1986-06-01

    An advanced concept, in-situ MHD conversion, is described for converting fusion energy to electricity. Considerable cost savings can be realized because of the conversion of thermal energy to electricity achieved in the blanket by means of magnetohydrodynamic (MHD) generators. The external disk generator, also described, is another application of the MHD idea, which may have certain advantages over the in-situ scheme for advanced-fuel tokamaks. The feature that makes these schemes fusion-specific is the novel use of the electro-magnetic radiation naturally emitted by the plasma. The synchrotron radiation can be used either to heat the nonequilibrium MHD plasma, or possibly improve its stability. A Rankine cycle with cesium-seeded mercury as a working fluid is used in either case. Performance predictions by a quasi-one-dimensional model are presented. An experiment to determine the effect of microwave radiation on channel performance is planned.

  15. Tropical botanical gardens: at the in situ ecosystem management frontier.

    PubMed

    Chen, Jin; Cannon, Charles H; Hu, Huabin

    2009-11-01

    Tropical botanical gardens (TBGs) should have a leading role in in situ conservation by directly promoting several initiatives, including the reintroduction of important or valuable native species, focused habitat restoration, 'assisted migration' of species that are vulnerable to climate change, and creative local collaboration with governments, NGOs and indigenous peoples. Compared with temperate gardens, TBGs face heightened challenges for ex situ conservation, including greater absolute amounts of biodiversity, need for resource mobilization, risk of introducing invasive species and potential genetic introgression within living collections. Meanwhile, the ecosystems surrounding TBGs have undergone widespread and rapid conversion. Here, we provide several illustrations of the effectiveness of TBGs in achieving their mission of preserving tropical biodiversity at the frontier of in situ ecosystem management.

  16. Local and transient nanoscale strain mapping during in situ deformation

    NASA Astrophysics Data System (ADS)

    Gammer, C.; Kacher, J.; Czarnik, C.; Warren, O. L.; Ciston, J.; Minor, A. M.

    2016-08-01

    The mobility of defects such as dislocations controls the mechanical properties of metals. This mobility is determined both by the characteristics of the defect and the material, as well as the local stress and strain applied to the defect. Therefore, the knowledge of the stress and strain during deformation at the scale of defects is important for understanding fundamental deformation mechanisms. Here, we demonstrate a method of measuring local stresses and strains during continuous in situ deformation with a resolution of a few nanometers using nanodiffraction strain mapping. Our results demonstrate how large multidimensional data sets captured with high speed electron detectors can be analyzed in multiple ways after an in situ TEM experiment, opening the door for true multimodal analysis from a single electron scattering experiment.

  17. Underwater microscopy for in situ studies of benthic ecosystems.

    PubMed

    Mullen, Andrew D; Treibitz, Tali; Roberts, Paul L D; Kelly, Emily L A; Horwitz, Rael; Smith, Jennifer E; Jaffe, Jules S

    2016-07-12

    Microscopic-scale processes significantly influence benthic marine ecosystems such as coral reefs and kelp forests. Due to the ocean's complex and dynamic nature, it is most informative to study these processes in the natural environment yet it is inherently difficult. Here we present a system capable of non-invasively imaging seafloor environments and organisms in situ at nearly micrometre resolution. We overcome the challenges of underwater microscopy through the use of a long working distance microscopic objective, an electrically tunable lens and focused reflectance illumination. The diver-deployed instrument permits studies of both spatial and temporal processes such as the algal colonization and overgrowth of bleaching corals, as well as coral polyp behaviour and interspecific competition. By enabling in situ observations at previously unattainable scales, this instrument can provide important new insights into micro-scale processes in benthic ecosystems that shape observed patterns at much larger scales.

  18. Design, control and in situ visualization of gas nitriding processes.

    PubMed

    Ratajski, Jerzy; Olik, Roman; Suszko, Tomasz; Dobrodziej, Jerzy; Michalski, Jerzy

    2010-01-01

    The article presents a complex system of design, in situ visualization and control of the commonly used surface treatment process: the gas nitriding process. In the computer design conception, analytical mathematical models and artificial intelligence methods were used. As a result, possibilities were obtained of the poly-optimization and poly-parametric simulations of the course of the process combined with a visualization of the value changes of the process parameters in the function of time, as well as possibilities to predict the properties of nitrided layers. For in situ visualization of the growth of the nitrided layer, computer procedures were developed which make use of the results of the correlations of direct and differential voltage and time runs of the process result sensor (magnetic sensor), with the proper layer growth stage. Computer procedures make it possible to combine, in the duration of the process, the registered voltage and time runs with the models of the process.

  19. Synthesis of nitrate sodalite: An in situ scanning calorimetric study

    NASA Astrophysics Data System (ADS)

    Liu, Qingyuan; Navrotsky, Alexandra

    2007-04-01

    The formation of nitrate sodalite, an important constituent of the resilient heels at DOE nuclear waste storage sites, was closely followed by oven synthesis, in situ calorimetry as a function of heating rate from 0.01 to 0.1 °C/min and X-ray diffraction. A transition sequence of amorphous-zeolite A-sodalite-cancrinite was confirmed. For in situ synthesis calorimetry, the heat flow peaks related to zeolite A formation are shifted to higher temperatures as heating rate increases. Although the end products are mostly nitrate sodalite, no calorimetric signals associated with zeolite A to sodalite conversion are detected. This suggests that the enthalpy of formation of zeolite A and sodalite are very similar and the zeolite A to sodalite conversion enthalpy is small. This conclusion is in accord with previous measurements by oxide melt solution calorimetry.

  20. Local and transient nanoscale strain mapping during in situ deformation

    SciTech Connect

    Gammer, C. E-mail: aminor@lbl.gov; Ciston, J.; Kacher, J.; Minor, A. M. E-mail: aminor@lbl.gov; Czarnik, C.; Warren, O. L.

    2016-08-22

    The mobility of defects such as dislocations controls the mechanical properties of metals. This mobility is determined both by the characteristics of the defect and the material, as well as the local stress and strain applied to the defect. Therefore, the knowledge of the stress and strain during deformation at the scale of defects is important for understanding fundamental deformation mechanisms. Here, we demonstrate a method of measuring local stresses and strains during continuous in situ deformation with a resolution of a few nanometers using nanodiffraction strain mapping. Our results demonstrate how large multidimensional data sets captured with high speed electron detectors can be analyzed in multiple ways after an in situ TEM experiment, opening the door for true multimodal analysis from a single electron scattering experiment.

  1. Local and transient nanoscale strain mapping during in situ deformation

    DOE PAGES

    Gammer, C.; Kacher, J.; Czarnik, C.; ...

    2016-08-26

    The mobility of defects such as dislocations controls the mechanical properties of metals. This mobility is determined both by the characteristics of the defect and the material, as well as the local stress and strain applied to the defect. Therefore, the knowledge of the stress and strain during deformation at the scale of defects is important for understanding fundamental deformation mechanisms. In this paper, we demonstrate a method of measuring local stresses and strains during continuous in situ deformation with a resolution of a few nanometers using nanodiffraction strain mapping. Finally, our results demonstrate how large multidimensional data sets capturedmore » with high speed electron detectors can be analyzed in multiple ways after an in situ TEM experiment, opening the door for true multimodal analysis from a single electron scattering experiment.« less

  2. Local and transient nanoscale strain mapping during in situ deformation

    SciTech Connect

    Gammer, C.; Kacher, J.; Czarnik, C.; Warren, O. L.; Ciston, J.; Minor, A. M.

    2016-08-26

    The mobility of defects such as dislocations controls the mechanical properties of metals. This mobility is determined both by the characteristics of the defect and the material, as well as the local stress and strain applied to the defect. Therefore, the knowledge of the stress and strain during deformation at the scale of defects is important for understanding fundamental deformation mechanisms. In this paper, we demonstrate a method of measuring local stresses and strains during continuous in situ deformation with a resolution of a few nanometers using nanodiffraction strain mapping. Finally, our results demonstrate how large multidimensional data sets captured with high speed electron detectors can be analyzed in multiple ways after an in situ TEM experiment, opening the door for true multimodal analysis from a single electron scattering experiment.

  3. In situ bioventing in deep soils at arid sites

    SciTech Connect

    Frishmuth, R.A.; Ratz, J.W.; Blicker, B.R.; Hall, J.F.; Downey, D.C.

    1995-11-01

    In situ bioventing has been shown to be a cost-effective remedial alternative for vadose zone soils. The success of the technology relies on the ability of indigenous soil microorganisms to utilize petroleum hydrocarbon contaminants as a primary metabolic substrate. Soil microbial populations are typically elevated in shallow soils due to an abundance of naturally occurring substrates and nutrients, but may be limited at greater depths due to a lack of these constituents. Therefore, the effectiveness of in situ bioventing is questionable in contaminated soil zones that extend far below the ground surface. Also, because the soil microbial population relies on soil moisture to sustain hydrocarbon degradation, the viability of bioventing is questionable in arid climates, where the soil moisture content is suspected to be minimal.

  4. In Situ Formation and Dynamical Evolution of Hot Jupiter Systems

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin; Bodenheimer, Peter H.; Laughlin, Gregory P.

    2016-10-01

    Hot Jupiters, giant extrasolar planets with orbital periods shorter than ˜10 days, have long been thought to form at large radial distances, only to subsequently experience long-range inward migration. Here, we offer the contrasting view that a substantial fraction of the hot Jupiter population formed in situ via the core-accretion process. We show that under conditions appropriate to the inner regions of protoplanetary disks, rapid gas accretion can be initiated by super-Earth-type planets, comprising 10-20 Earth masses of refractory material. An in situ formation scenario leads to testable consequences, including the expectation that hot Jupiters should frequently be accompanied by additional low-mass planets with periods shorter than ˜100 days. Our calculations further demonstrate that dynamical interactions during the early stages of planetary systems’ lifetimes should increase the inclinations of such companions, rendering transits rare. High-precision radial velocity monitoring provides the best prospect for their detection.

  5. In situ transmission electron microscopy for magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Ngo, Duc-The; Theil Kuhn, Luise

    2016-12-01

    Nanomagnetism is a subject of great interest because of both application and fundamental aspects in which understanding of the physical and electromagnetic structure of magnetic nanostructures is essential to explore the magnetic properties. Transmission electron microscopy (TEM) is a powerful tool that allows understanding of both physical structure and micromagnetic structure of the thin samples at nanoscale. Among TEM techniques, in situ TEM is the state-of-the-art approach for imaging such structures in dynamic experiments, reconstructing a real-time nanoscale picture of the properties-structure correlation. This paper aims at reviewing and discussing in situ TEM magnetic imaging studies, including Lorentz microscopy and electron holography in TEM, applied to the research of magnetic nanostructures.

  6. Field studies of in-situ soil washing

    SciTech Connect

    Nash, J.H.

    1987-12-01

    The EPA and US Air Force conducted a research test program to demonstrate the removal of hydrocarbons and chlorinated hydrocarbons from a sandy soil by in situ soil washing using surfactants. Contaminated soil from the fire-training area of Volk Air National Guard Base, WI, was first taken to a laboratory for characterization. At the laboratory, the soil was recompacted into glass columns creating a simulated in-situ environment. Under gravity flow, 12 pore volumes of aqueous surfactant solutions were passed through each of the columns. Gas chromatograph (GC) analyses were used on the washing effluent and soil to determine removal efficiency (RE). The results of these tests were highly encouraging. Treated effluent was discharged directly to the on-base aerobic-treatment lagoons.

  7. Design, Control and in Situ Visualization of Gas Nitriding Processes

    PubMed Central

    Ratajski, Jerzy; Olik, Roman; Suszko, Tomasz; Dobrodziej, Jerzy; Michalski, Jerzy

    2010-01-01

    The article presents a complex system of design, in situ visualization and control of the commonly used surface treatment process: the gas nitriding process. In the computer design conception, analytical mathematical models and artificial intelligence methods were used. As a result, possibilities were obtained of the poly-optimization and poly-parametric simulations of the course of the process combined with a visualization of the value changes of the process parameters in the function of time, as well as possibilities to predict the properties of nitrided layers. For in situ visualization of the growth of the nitrided layer, computer procedures were developed which make use of the results of the correlations of direct and differential voltage and time runs of the process result sensor (magnetic sensor), with the proper layer growth stage. Computer procedures make it possible to combine, in the duration of the process, the registered voltage and time runs with the models of the process. PMID:22315536

  8. Autoregulation of the 26S proteasome by in situ ubiquitination

    PubMed Central

    Jacobson, Andrew D.; MacFadden, Andrea; Wu, Zhiping; Peng, Junmin; Liu, Chang-Wei

    2014-01-01

    The 26S proteasome degrades ubiquitinated proteins, and proteasomal degradation controls various cellular events. Here we report that the human 26S proteasome is ubiquitinated, by which the ubiquitin receptors Adrm1 and S5a, the ATPase subunit Rpt5, and the deubiquitinating enzyme Uch37 are ubiquitinated in situ by proteasome-associating ubiquitination enzymes. Ubiquitination of these subunits significantly impairs the 26S proteasome's ability to bind, deubiquitinate, and degrade ubiquitinated proteins. Moreover, ubiquitination of the 26S proteasome can be antagonized by proteasome-residing deubiquitinating enzymes, by the binding of polyubiquitin chains, and by certain cellular stress, indicating that proteasome ubiquitination is dynamic and regulated in cells. We propose that in situ ubiquitination of the 26S proteasome regulates its activity, which could function to adjust proteasomal activity in response to the alteration of cellular ubiquitination levels. PMID:24743594

  9. Deploying in situ bioremediation at the Hanford Site

    SciTech Connect

    Truex, M.J.; Johnson, C.D.; Newcomer, D.R.; Doremus, L.A.; Hooker, B.S.; Peyton, B.M.; Skeen, R.S.; Chilakapati, A.

    1994-11-01

    An innovative in-situ bioremediation technology was developed by Pacific Northwest Laboratory (PNL) to destroy nitrate and carbon tetrachloride (CC1{sub 4}) in the Hanford ground water. The goal of this in-situ treatment process is to stimulate native microorganisms to degrade nitrate and CCl{sub 4}. Nutrient solutions are distributed in the contaminated aquifer to create a biological treatment zone. This technology is being demonstrated at the US Department of Energy`s Hanford Site to provide the design, operating, and cost information needed to assess its effectiveness in contaminated ground water. The process design and field operations for demonstration of this technology are influenced by the physical, chemical, and microbiological properties observed at the site. A description of the technology is presented including the well network design, nutrient injection equipment, and means for controlling the hydraulics and microbial reactions of the treatment process.

  10. Kinetics of in situ bioremediation of Hanford groundwater

    SciTech Connect

    Skeen, R.S.; Cote, S.M.; Truex, M.J.; Petersen, J.N.

    1992-04-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy`s (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate, carbon tetrachloride (CCl{sub 4}), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and may require the remediation of existing contaminated groundwaters. In situ bioremediation is one technology currently being developed at Hanford to meet the need for cost effective technologies to clean groundwater contaminated with CCl{sub 4}, nitrate, and other organic and inorganic contaminants. This paper focuses on the latest results of an on-going effort to quantify the biological and chemical reactions that would occur during in situ bioremediation.

  11. Kinetics of in situ bioremediation of Hanford groundwater

    SciTech Connect

    Skeen, R.S.; Cote, S.M.; Truex, M.J. ); Petersen, J.N. . Dept. of Chemical Engineering)

    1992-04-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 40+ years of operations at the US Department of Energy's (DOE) Hanford Site. Some of these wastes were discharged to the soil column and many of the waste components, including nitrate, carbon tetrachloride (CCl[sub 4]), and several radionuclides, have been detected in the Hanford groundwater. Current DOE policy prohibits the disposal of contaminated liquids directly to the environment, and may require the remediation of existing contaminated groundwaters. In situ bioremediation is one technology currently being developed at Hanford to meet the need for cost effective technologies to clean groundwater contaminated with CCl[sub 4], nitrate, and other organic and inorganic contaminants. This paper focuses on the latest results of an on-going effort to quantify the biological and chemical reactions that would occur during in situ bioremediation.

  12. Targeting human dendritic cells in situ to improve vaccines.

    PubMed

    Sehgal, Kartik; Dhodapkar, Kavita M; Dhodapkar, Madhav V

    2014-11-01

    Dendritic cells (DCs) provide a critical link between innate and adaptive immunity. The potent antigen presenting properties of DCs makes them a valuable target for the delivery of immunogenic cargo. Recent clinical studies describing in situ DC targeting with antibody-mediated targeting of DC receptor through DEC-205 provide new opportunities for the clinical application of DC-targeted vaccines. Further advances with nanoparticle vectors which can encapsulate antigens and adjuvants within the same compartment and be targeted against diverse DC subsets also represent an attractive strategy for targeting DCs. This review provides a brief summary of the rationale behind targeting dendritic cells in situ, the existing pre-clinical and clinical data on these vaccines and challenges faced by the next generation DC-targeted vaccines. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Method of rubblization for in-situ oil shale processing

    NASA Technical Reports Server (NTRS)

    Yang, Lien C. (Inventor)

    1985-01-01

    A method that produces a uniformly rubblized oil shale bed of desirable porosity for underground, in-situ heat extraction of oil. Rubblization is the generation of rubble of various sized fragments. The method uses explosive loadings lying at different levels in adjacent holes and detonation of the explosives at different levels in sequence to achieve the fracturing and the subsequent expansion of the fractured oil shale into excavated rooms both above and below the hole pattern.

  14. In-situ sensors for product reliability monitoring

    NASA Astrophysics Data System (ADS)

    Mishra, Satchidananda; Pecht, Michael; Goodman, Douglas L.

    2002-04-01

    Some advantages of predicting reliability include providing advance warning signs of failure, and the reduction of life cycle costs by reducing inspection and unscheduled maintenance. However, predictions can be inaccurate if they do not account for the actual environments that the product is subjected to in its li8fe cycle. This paper describes an in-situ sensor (prognostic monitor) approach, which can be used to estimate the accumulated damage and the remaining life of semiconductor devices.

  15. TRIO-01 experiment: in-situ tritium recovery results

    SciTech Connect

    Clemmer, R.G.; Finn, P.A.; Billone, M.C.; Misra, B.; Greenwood, L.R.; Dyer, F.F.; Dudley, I.T.; Bate, L.C.; Clemmer, E.D.; Fisher, P.W.

    1983-01-01

    The TRIO-01 experiment was designed to test in-situ tritium recovery and heat transfer performance of a candidate solid breeder, ..gamma..-LiAlO/sub 2/. The results showed that nearly all the tritium generated was recovered. Only < 0.1 wppM tritium remained in the solid after irradiation testing. The heat transfer performance showed that temperature profiles can be effectively controlled.

  16. Hydrogeologic Effects of In-Situ Groundwater Treatment Using Biodegradation

    DTIC Science & Technology

    1987-06-15

    research we have tried to quantify the changes in hydraulic parameters due to microbial activity and to outline the importance of these changes for the...to identify possible in-situ reclamation schemes. * Collection of data from laboratory permeameter experiments to determine changes in permeability...is subject to changes due to permeability reductions. The addition of nutrients and oxygen source in the recharge water is responsible for

  17. Laparoscopic removal of a large laparotomy pad forgotten in situ.

    PubMed

    Uranüs, S; Schauer, C; Pfeifer, J; Dagcioglu, A

    1995-02-01

    Objects forgotten during surgery are still an important complication with ethical and forensic implications. This case report describes a splenectomized patient with type II Hodgkin's disease. A large laparotomy pad (68 x 48 cm) forgotten in situ during a staging operation 6 months previously was removed laparoscopically. In asplenic patients with a permanent immune deficiency it is especially advantageous to perform surgery via the "closed" route whenever possible.

  18. Efficient Airframe Management Using In-Situ Structural Health Monitoring

    DTIC Science & Technology

    2012-07-01

    Efficient Airframe Management Using In-Situ Structural Health Monitoring  M. M. DERRISO , M. S. LEONARD, M. P. DESIMIO and S. E. OLSON...at predetermined times regardless of their actual conditions. This _____________ Mark M. Derriso and Matthew S. Leonard, Air Force Research...Health Monitoring Literature: 1996‐2001,” Los Alamos National Laboratory Report LA-13976-MS, February 2004. 6. Derriso , M., S. Olson, M. DeSimio, and

  19. Pneumatic Regolith Transfer Systems for In Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Mueller, R. P.; Townsend, I. I.; Mantovani, J. G.; Zacny, Kris A.; Craft, Jack

    2010-01-01

    This slide presentation reviews the testing of a pneumatic system for transfering regolith, to be used for In Situ Resource Utilization (ISRU). Using both the simulated microgravity of parabolic flight and ground testing, the tests demonstrated that lunar regolith can be conveyed pneumatically into a simulated ISRU oxygen production plant reactor. The ground testing also demonstrated that the regolith can be expelled from the ISRU reactor for disposal or for other resource processing.

  20. In Situ Resource Utilization (ISRU) Technical Interchange Meeting

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This volume contains abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU) Technical Interchange Meeting, February 4-5, 1997, at the Lunar and Planetary Institute, Houston, Texas. Abstracts are arranged in order of presentation at the meetings, with corresponding page numbers shown in the enclosed agenda. Logistics, administration, and publication support for this meeting were provided by the staff of the Publications and Program Services Department at the Lunar and Planetary Institute.

  1. Towards microfluidic reactors for in situ synchrotron infrared studies

    NASA Astrophysics Data System (ADS)

    Silverwood, I. P.; Al-Rifai, N.; Cao, E.; Nelson, D. J.; Chutia, A.; Wells, P. P.; Nolan, S. P.; Frogley, M. D.; Cinque, G.; Gavriilidis, A.; Catlow, C. R. A.

    2016-02-01

    Anodically bonded etched silicon microfluidic devices that allow infrared spectroscopic measurement of solutions are reported. These extend spatially well-resolved in situ infrared measurement to higher temperatures and pressures than previously reported, making them useful for effectively time-resolved measurement of realistic catalytic processes. A data processing technique necessary for the mitigation of interference fringes caused by multiple reflections of the probe beam is also described.

  2. Fiber field-effect device via in situ channel crystallization.

    PubMed

    Danto, Sylvain; Sorin, Fabien; Orf, Nicholas D; Wang, Zheng; Speakman, Scott A; Joannopoulos, John D; Fink, Yoel

    2010-10-01

    The in situ crystallization of the incorporated amorphous semiconductor within the multimaterial fiber device yields a large decrease in defect density and a concomitant five-order-of-magnitude decrease in resistivity of the novel metal-insulator-crystalline semiconductor structure. Using a post-drawing crystallization process, the first tens-of-meters-long single-fiber field-effect device is demonstrated. This work opens significant opportunities for incorporating higher functionality in functional fibers and fabrics.

  3. Ductal carcinoma in situ - update on risk assessment and management.

    PubMed

    Pang, Jia-Min B; Gorringe, Kylie L; Fox, Stephen B

    2016-01-01

    Ductal carcinoma in situ (DCIS) accounts for ~20-25% of breast cancers. While DCIS is not life-threatening, it may progress to invasive carcinoma over time, and treatment intended to prevent invasive progression may itself cause significant morbidity. Accurate risk assessment is therefore necessary to avoid over- or undertreatment of an individual patient. In this review we will outline the evidence for current management of DCIS, discuss approaches to DCIS risk assessment and challenges facing identification of novel DCIS biomarkers.

  4. DSBCapture: in situ capture and sequencing of DNA breaks.

    PubMed

    Lensing, Stefanie V; Marsico, Giovanni; Hänsel-Hertsch, Robert; Lam, Enid Y; Tannahill, David; Balasubramanian, Shankar

    2016-10-01

    Double-strand DNA breaks (DSBs) continuously arise and cause mutations and chromosomal rearrangements. Here, we present DSBCapture, a sequencing-based method that captures DSBs in situ and directly maps these at single-nucleotide resolution, enabling the study of DSB origin. DSBCapture shows substantially increased sensitivity and data yield compared with other methods. Using DSBCapture, we uncovered a striking relationship between DSBs and elevated transcription within nucleosome-depleted chromatin.

  5. In situ remediation integrated program: Development of containment technology

    SciTech Connect

    Peterson, M.E.

    1994-08-01

    The In Situ Remediation Integrated Program (ISR IP) is supporting the development of subsurface containment barrier technology for use in site restoration applications at contaminated sites throughout the US Department of Energy (DOE) complex. The types of subsurface barriers being developed include impermeable barriers and sorbent barriers. The specific containment technology projects described in this paper include frozen soil barriers, flowable grout techniques, hydraulic and diffusion barriers, horizontal grout barriers, chemically enhanced barriers, and viscous liquid barriers.

  6. Reductive Anaerobic Biological In Situ Treatment Technology (RABITT) Treatability Testing

    DTIC Science & Technology

    2003-06-01

    Research Laboratory (AFRL) at Tyndall AFB, Florida. ESTCP documentation was prepared jointly by Mr. Jeff Morse and Dr. Bruce Alleman of Battelle...October 1998. www.frtr.gov. 11. Major, D.W., E. Hodgins , and B. Butler. 1991. “Field and Laboratory Evidence of In Situ Biotransformation of...last updated on 8/13/01). A-1 APPENDIX A POINTS OF CONTACT Point of Contact (Name) Organization (Name & Address) Phone/Fax/E-mail Role in Project Bruce

  7. In situ and remote measurements of ions escaping from Venus

    NASA Astrophysics Data System (ADS)

    Kollmann, P.; Brandt, P. C.

    2013-12-01

    Venus is thought to lose a large fraction of its atmosphere in the form ions, mainly via pickup. The relative loss rate of the exosphere as neutrals or ions is not known, nor is the flux of escaping ions well constrained. Knowledge of these processes will shed light on the role an intrinsic magnetic field has in atmospheric erosion. We use the complementary in-situ plasma and energetic neutral atom (ENA) measurements from the Venus Express (VEx) spacecraft in order to constrain the ion escape. VEx completed about 2500 orbits to date and reached altitudes as low as 200km. The ASPERA/IMA instrument measured directional proton and oxygen ion spectra in the 10eV to 40keV range. We bin the data accumulated over the mission in space and bulk flow direction, yielding a direct measure of the local ion escape flux. While such in-situ measurements provide data without ambiguity, they are limited by the orbital coverage. This is why we include remote ENA measurements from the ASPERA/NPD (100eV to 10keV) instrument to our study. ENAs are created when escaping ions charge exchange with the high atmosphere atoms or molecules. We have done an exhaustive analysis of the data, excluding time periods of instrument contamination. Most ENA emission originates from low altitudes above Venus' limb. These measurements will be compared with the in-situ data, which allows constraining the atmospheric density at high altitudes. Interestingly, there are also ENA emissions from other directions, which were not sampled in-situ. This allows us to put a lower limit to the escape from these regions.

  8. Chromosome in situ suppression hybridisation in clinical cytogenetics.

    PubMed Central

    Hulten, M A; Gould, C P; Goldman, A S; Waters, J J

    1991-01-01

    The use of chromosome in situ suppression hybridisation with whole chromosome libraries has previously been reported by various research laboratories to be an effective method of identifying specific human chromosomal material. As a clinical cytogenetic service laboratory we have used the technique as a complement to diagnosis by classical chromosome banding. In three examples of structural rearrangements the potential use of the 'chromosome painting' method is assessed for its ability to enhance the routine cytogenetic service currently available. Images PMID:1956055

  9. Mechanical testing - In situ fracture device for Auger electron spectroscopy

    NASA Technical Reports Server (NTRS)

    Moorhead, R. D.

    1976-01-01

    An in situ fracture device for Auger spectroscopy is described. The device is designed to handle small tensile specimens or small double-cantilever beam specimens and is fully instrumented with load and displacement transducers so that quantitative stress-strain measurements can be made directly. Some initial test results for specimens made from 4130 and 1020 steel are presented. Results indicate that impurity segregation at interfaces other than grain boundary may play a significant role in the mechanism of ductile fracture.

  10. In-Situ Surface EXAFS at Chemically Modified Electrodes.

    DTIC Science & Technology

    1987-07-28

    characterization of underpotentially deposited copper on gold(ll) electrodes. [12] We now present an in-situ surface EXAFS study of electropolymerized... deposition or adsorption of metallic adlayers (6] or transition metal complexes. [7] In addition the electrode can act as a simple electron shuttle to...structure at all stages of polymer deposition . These values correlate very well with the known coordination member of six and a Ru-N distance of 2.056 A

  11. In Situ Reproductive Rate of Freshwater Caulobacter spp.†

    PubMed Central

    Poindexter, Jeanne S.; Pujara, Kanan P.; Staley, James T.

    2000-01-01

    Electron microscope grids were submerged in Lake Washington, Seattle, Wash., in June 1996 as bait to which Caulobacter sp. swarmers would attach and on which they would then reproduce in situ. Enumeration of bands in the stalks of attached cells implied that the caulobacters were completing approximately three reproductive cycles per day. A succession of morphological types of caulobacters occurred, as well as an episode of bacteriovore grazing that slowed the accumulation of caulobacters and prevented the aging of the population. PMID:10966435

  12. Towards an Autonomous Space In-Situ Marine Sensorweb

    NASA Technical Reports Server (NTRS)

    Chien, S.; Doubleday, J.; Tran, D.; Thompson, D.; Mahoney, G.; Chao, Y.; Castano, R.; Ryan, J.; Kudela, R.; Palacios, S.; Foley, D.; Balasuriya, A.; Schmidt, H.; Schofield, O.; Arrott, M.; Meisinger, M.; Mandl, D.; Frye, S.; Ong, L.; Cappelaere, P.

    2009-01-01

    We describe ongoing efforts to integrate and coordinate space and marine assets to enable autonomous response to dynamic ocean phenomena such as algal blooms, eddies, and currents. Thus far we have focused on the use of remote sensing assets (e.g. satellites) but future plans include expansions to use a range of in-situ sensors such as gliders, autonomous underwater vehicles, and buoys/moorings.

  13. Direct visualization of identified and newly synthesized proteins in situ

    PubMed Central

    Dieck, Susanne tom; Kochen, Lisa; Hanus, Cyril; Bartnik, Ina; Nassim-Assir, Belquis; Merk, Katrin; Mosler, Thorsten; Garg, Sakshi; Bunse, Stefanie; Tirrell, David A.; Schuman, Erin M.

    2015-01-01

    Protein synthesis is a dynamic process to tune the cellular proteome to internal and external demands. Metabolic labeling approaches identify the general proteomic response but missing is a tool to visualize within cells specific newly synthesized proteins. Here we describe a technique that couples non-canonical amino acid tagging or puromycylation with the proximity-ligation assay to visualize identified newly synthesized proteins and monitor their origin, redistribution and turnover in situ. PMID:25775042

  14. Thoracolumbar fracture reduction by percutaneous in situ contouring.

    PubMed

    Charles, Yann Philippe; Walter, Axel; Schuller, Sébastien; Aldakheel, Dakheel; Steib, Jean-Paul

    2012-11-01

    Percutaneous in situ contouring is based on bilateral bending of rods on the spine, thus increasing lordosis at the fracture. It was analyzed if this technique would provide a better reduction than prone positioning and how sagittal alignment would behave. Twenty-nine patients were operated using in situ contouring and selective anterior fusion for non-neurologic A2, A3 or B2 fractures. Clinical results were assessed prospectively using visual analog scale (VAS) and Oswestry Disability Index (ODI). The radiographic deformity correction was measured by sagittal index and regional kyphosis. Sagittal balance was assessed using kyphosis, lordosis, T9 tilt, pelvic incidence, pelvic tilt and sacral slope. Posterior wall fragment reduction was evaluated by computed tomography. After 2 years, VAS and ODI were comparable to the status prior to the accident. The sagittal index was 19.7° preoperatively, 5.3° after prone positioning and -1.1° after in situ contouring (p < 0.001). The loss of correction was 2.4°, mainly during the first 3 months. Similar observations were made for regional kyphosis. The sagittal spino-pelvic alignment was stable postoperatively. A preoperative canal obstruction ≥50 % was observed in 16 patients, and the fragments migrated anteriorly in all patients. Percutaneous instrumentation and anterior fusion provides good clinical results. In situ contouring increases lordosis obtained by prone positioning. Anterior column lengthening and ligamentotaxis reduce posterior wall fragments, which decompress the canal without laminectomy. The fusion of anterior defects prevents the loss of correction and provides a stable sagittal profile. The instrumentation may be removed without damaging the paravertebral muscles and loss of correction.

  15. Microcantilever Sensors for In-Situ Subsurface Characterization

    SciTech Connect

    Thundat, Thomas G.; Zhiyu Hu; Brown, Gilbert M.; Baohua Gu

    2006-06-01

    Real-time, in-situ analysis is critical for decision makers in environmental monitoring, but current techniques for monitoring and characterizing radionuclides rely primarily on liquid scintillation counting, ICP-MS, and spectrofluorimetry, which require sample handling and labor intensive lengthy analytical procedures. Other problems that accompany direct sampling include adherence to strict holding times and record maintenance for QA/QC procedures. Remote, automated sensing with direct connection to automated data management is preferred.

  16. In situ growth rate measurement of selective LPCVD of tungsten

    SciTech Connect

    Holleman, J.; Hasper, A.; Middelhoek, J. )

    1991-04-01

    This paper reports on the reflectance measurement during the selective deposition of W on Si covered with an insulator rating proven to be a convenient method to monitor the W deposition. The reflectance change during deposition allows the in situ measurement of the deposition rate. The influence of surface roughening due to either the W growth or an etching pretreatment of the wafer is modeled, as well as the effect of selectivity loss and lateral overgrowth.

  17. Site characterization and remediation monitoring using in situ subsurface sensors

    SciTech Connect

    Li, D.X.

    1995-09-01

    Site characterization and remediation monitoring using in situ sensors is potentially a more effective and inexpensive alternative to current methods of sample collection and analysis. Gaseous components of a system are the most mobile and easiest to monitor. Soil gas measurements can not only indicate the presence of hydrocarbon contamination, but also provide important quantitative information regarding the progress of bioremediation efforts and the area of influence of air sparging or soil venting. In situ subsurface sensors can provide potentially more accurate data by minimizing disturbance of subsurface conditions and allow continuous and unattended measurements over a long period of time. Tests of in situ soil gas sensors show that the sensors provide rapid and accurate data on soil gas pressures and vapor phase concentrations. The sensors perform well in permeable, unsaturated soil environments and recover completely after being submerged during temporary saturated conditions. The pressure and subsurface oxygen sensors are well suited for monitoring gas flow and oxygen consumption in the vadose zone during air sparging and bioventing. These sensors have been used to develop a new dynamic technique of evaluating in situ respiration rates during air injection or vapor extraction which has several advantages over the traditional static oxygen uptake method. By using a subsurface oxygen sensor, the dynamic technique offers continuous monitoring capability during the bioventing process. Unlike the traditional respiration test that measures localized respiration rates, this method determines an average respiration rate in the air flow path. Because the measurements can be made at the startup of a remediation process, the operation can run without interruption.

  18. Radio frequency heating for in-situ remediation of DNAPL

    SciTech Connect

    Kasevich, R.S.

    1996-08-01

    In-situ radio frequency (RF) heating technology for treating soils contaminated with dense nonaqueous phase liquids (DNAPLs) is described. RF imparts heat to non-conducting materials through the application of carefully controlled RF transmissions, improving contaminant flow characteristics and facilitating separation and removal from subsurface soils. The paper outlines advantages and limitations of RF remediation, process operations, general technology considerations, low permeability media considerations, commercial availability, and costs. Two case histories of RF remediation are briefly summarized. 13 refs., 10 figs.

  19. Ignition technique for an in situ oil shale retort

    DOEpatents

    Cha, Chang Y.

    1983-01-01

    A generally flat combustion zone is formed across the entire horizontal cross-section of a fragmented permeable mass of formation particles formed in an in situ oil shale retort. The flat combustion zone is formed by either sequentially igniting regions of the surface of the fragmented permeable mass at successively lower elevations or by igniting the entire surface of the fragmented permeable mass and controlling the rate of advance of various portions of the combustion zone.

  20. Scaling considerations for modeling the in situ vitrification process

    SciTech Connect

    Langerman, M.A.; MacKinnon, R.J.

    1990-09-01

    Scaling relationships for modeling the in situ vitrification waste remediation process are documented based upon similarity considerations derived from fundamental principles. Requirements for maintaining temperature and electric potential field similarity between the model and the prototype are determined as well as requirements for maintaining similarity in off-gas generation rates. A scaling rationale for designing reduced-scale experiments is presented and the results are assessed numerically. 9 refs., 6 figs.

  1. TRIO-01 experiment: in-situ tritium-recovery results

    SciTech Connect

    Clemmer, R.G.; Finn, P.A.; Billone, M.C.; Misra, B.; Arons, R.M.; Poeppel, R.B.; Dyer, F.F.; Dudley, I.T.; Bate, L.C.; Clemmer, E.D.

    1983-08-01

    The TRIO-01 experiment is a test of in-situ tritium recovery from ..gamma..-LiAlO/sub 2/ with test conditions chosen to simulate those anticipated in fusion power reactors. A status report is presented which describes qualitatively the results observed during the irradiation phase of the experiment. Both the rate of tritium release and the chemical forms of tritium were measured using a helium sweep gas which flowed past the breeder material to a gas analysis system.

  2. TRIO-01 experiment: in-situ tritium recovery results

    SciTech Connect

    Clemmer, R.G.; Finn, P.A.; Billone, M.C.; Misra, B.; Arons, R.M.; Poeppel, R.B.; Dyer, F.F.; Dudley, I.T.; Bate, L.C.; Clemmer, E.D.

    1983-10-01

    The TRIO-01 experiment is a test of in-situ tritium recovery from ..gamma..-LiAlO/sub 2/ with test conditions chosen to simulate those anticipated in fusion power reactors. A status report is presented which describes qualitatively the results observed during the irradiation phase of the experiment. Both the rate of tritium release and the chemical forms of tritium were measured using a helium sweep gas which flowed past the breeder material to a gas analysis system.

  3. Preparation and evaluation of nanoparticles loaded ophthalmic in situ gel.

    PubMed

    Kesarla, Rajesh; Tank, Tanvi; Vora, Pratik Ashwinbhai; Shah, Tanvi; Parmar, Sagar; Omri, Abdelwahab

    2016-09-01

    Conventional ophthalmic solutions often eliminate rapidly after administration and cannot provide and maintain an adequate concentration of drug in the pre-corneal area. Above problem can be overcome by the use of in situ gel forming systems that are instilled as drops in to the eye and undergo a sol-gel transition in the cul-de-sac. An ion sensitive polymer gellan gum was used as gelling agent which formed immediate gel and remained for extended time period. Nanoparticles of moxifloxacin, prepared by solvent evaporation, were separated by freeze drying. The rheological properties and in vitro drug release test of in situ gel loaded with nanoparticles were evaluated and compared with marketed preparation. In vitro release study demonstrated diffusion controlled release for moxifloxacin from formulations over a period of 12 h. The developed formulation was stable and showed enhanced contact time minimizing the frequency of administration. Confocal microscopy showed clear permeation of drug loaded nanoparticles across L/S of cornea. The formulation of moxifloxacin was found liquid at the formulated pH and formed gel in the presence of mono or divalent cations. The gel formed in situ showed sustained drug release over a period of 10-12 h. The formulations were less viscous before instillation and formed strong gel after instilling it into cul-de-sac. It is thus concluded that by adopting a systematic formulation approach, an optimum point can be reached in the shortest time with minimum efforts to achieve desirable rheological and in vitro release property for in situ gel forming system.

  4. In Situ Measurement of Ground-Surface Flow Resistivity

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.

    1984-01-01

    New instrument allows in situ measurement of flow resistivity on Earth's ground surface. Nonintrusive instrument includes specimen holder inserted into ground. Flow resistivity measured by monitoring compressed air passing through flow-meters; pressure gages record pressure at ground surface. Specimen holder with knife-edged inner and outer cylinders easily driven into ground. Air-stream used in measuring flow resistivity of ground enters through quick-connect fitting and exits through screen and venthole.

  5. In situ simulation training for neonatal resuscitation: an RCT.

    PubMed

    Rubio-Gurung, Sophie; Putet, Guy; Touzet, Sandrine; Gauthier-Moulinier, Hélène; Jordan, Isabelle; Beissel, Anne; Labaune, Jean-Marc; Blanc, Sébastien; Amamra, Nassira; Balandras, Catherine; Rudigoz, René-Charles; Colin, Cyrille; Picaud, Jean-Charles

    2014-09-01

    High-fidelity simulation is an effective tool in teaching neonatal resuscitation skills to professionals. We aimed to determine whether in situ simulation training (for ∼80% of the delivery room staff) improved neonatal resuscitation performed by the staff at maternities. A baseline evaluation of 12 maternities was performed: a random sample of 10 professionals in each unit was presented with 2 standardized scenarios played on a neonatal high-fidelity simulator. The medical procedures were video recorded for later assessments. The 12 maternities were then randomly assigned to receive the intervention (a 4-hour simulation training session delivered in situ for multidisciplinary groups of 6 professionals) or not receive it. All maternities were evaluated again at 3 months after the intervention. The videos were assessed by 2 neonatologists blinded to the pre-/postintervention as well as to the intervention/control groups. The performance was assessed using a technical score and a team score. After intervention, the median technical score was significantly higher for scenarios 1 and 2 for the intervention group compared with the control group (P = .01 and 0.004, respectively), the median team score was significantly higher (P < .001) for both scenarios. In the intervention group, the frequency of achieving a heart rate >90 per minute at 3 minutes improved significantly (P = .003), and the number of hazardous events decreased significantly (P < .001). In situ simulation training with multidisciplinary teams can effectively improve technical skills and teamwork in neonatal resuscitation. Copyright © 2014 by the American Academy of Pediatrics.

  6. In-situ bioremediation of TCE-contaminated groundwater

    SciTech Connect

    Travis, B.J.; Rosenberg, N.D.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). A barrier to wider use of in situ bioremediation technology is that results are often variable and difficult to predict. In situ bioremediation has shown some very notable and well publicized successes, but implementation of the technology is complex. An incomplete understanding of the effects of variable site characteristics and the lack of adequate tools to predict and measure success have made the design, control and validation of bioremediation more empirical than desired. The long-term objective of this project is to improve computational tools used to assess and optimize the expected performance of bioremediation at a site. An important component of the approach is the explicit inclusion of uncertainties and their effect on the end result. The authors have extended their biokinetics model to include microbial competition and predation processes. Predator species can feed on the microbial species that degrade contaminants, and the simulation studies show that species interactions must be considered when designing in situ bioremediation systems. In particular, the results for TCE indicate that protozoan grazing could reduce the amount of biodegradation by about 20%. These studies also indicate that the behavior of barrier systems can become complex due to predator grazing.

  7. Regulation of in situ to invasive breast carcinoma transition

    SciTech Connect

    Polyak, Kornelia; Hu, Min; Yao, Jun; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen, Haiyan; Carrasco, Daniel; Richardson, Andrea; Violette, Shelia; Gelman, Rebecca S.; Bissell, Mina J.; Schnitt, Stuart; Polyak, Kornelia

    2008-05-07

    The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed the role of myoepithelial cells and fibroblasts in the progression of in situ carcinomas using a xenograft model of human DCIS. Progression to invasion was promoted by fibroblasts, but inhibited by normal myoepithelial cells. The invasive tumor cells from these progressed lesions formed DCIS rather than invasive cancers when re-injected into naive mice. Molecular profiles of myoepithelial and epithelial cells isolated from primary normal and cancerous human breast tissue samples corroborated findings obtained in the xenograft model. These results provide the proof of principle that breast tumor progression could occur in the absence of additional genetic alterations and that tumor growth and progression could be controlled by replacement of normal myoepithelial inhibitory signals.

  8. Regulation of In Situ to Invasive Breast CarcinomaTransition

    SciTech Connect

    Hu, Min; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen,Haiyan; Carrasco, Daniel; Richardson, Andrea; Bissell, Mina; Violette,Shelia; Gelman, Rebecca S.; Schnitt, Stuart; Polyak, Kornelia

    2007-03-13

    The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed the role of myoepithelial cells and fibroblasts in the progression of in situ carcinomas using a xenograft model of human DCIS. Progression to invasion was promoted by fibroblasts, but inhibited by normal myoepithelial cells. The invasive tumor cells from these progressed lesions formed DCIS rather than invasive cancers when re-injected into naive mice. Molecular profiles of myoepithelial and epithelial cells isolated from primary normal and cancerous human breast tissue samples corroborated findings obtained in the xenograft model. These results provide the proof of principle that breast tumor progression could occur in the absence of additional genetic alterations and that tumor growth and progression could be controlled by replacement of normal myoepithelial inhibitory signals.

  9. Effect of Microorganisms on In Situ Uranium Mining

    PubMed Central

    Yates, Marylynn V.; Brierley, James A.; Brierley, Corale L.; Follin, Steven

    1983-01-01

    The extraction of some metal values, e.g., uranium or copper, may be accomplished by using solutions to remove metals from ore bodies without practicing conventional mining. This process is referred to as in situ leaching and has been used industrially to recover uranium. The growth of microbial populations during in situ leaching is believed to be one of the causes of flow path plugging in the ore body, which results in decreased uranium production. Leach solution and solid samples from well casings and submersible pumps were collected from an in situ mining operation experiencing plugging problems. Bacillus sp., Micrococcus sp., pseudomonads, and xanthomonads were isolated from these samples in concentrations of 105 CFU ml−1. A mixed culture of these organisms was inoculated into a uranium core specimen in the laboratory to assess the role of microbes in the plugging problem. A one-third decrease in permeability was effected in 16 days. Hydrogen peroxide (0.2 g liter−1) killed the microorganisms in the core and alleviated the plugging problem. Periodically injecting hydrogen peroxide into the ore body through the production wells may reduce microbial plugging problems. PMID:16346395

  10. In Situ Remediation Integrated Program: FY 1994 program summary

    SciTech Connect

    1995-04-01

    The US Department of Energy (DOE) established the Office of Technology Development (EM-50) as an element of the Office of Environmental Management (EM) in November 1989. In an effort to focus resources and address priority needs, EM-50 introduced the concept of integrated programs (IPs) and integrated demonstrations (IDs). The In Situ Remediation Integrated Program (ISR IP) focuses research and development on the in-place treatment of contaminated environmental media, such as soil and groundwater, and the containment of contaminants to prevent the contaminants from spreading through the environment. Using in situ remediation technologies to clean up DOE sites minimizes adverse health effects on workers and the public by reducing contact exposure. The technologies also reduce cleanup costs by orders of magnitude. This report summarizes project work conducted in FY 1994 under the ISR IP in three major areas: treatment (bioremediation), treatment (physical/chemical), and containment technologies. Buried waste, contaminated soils and groundwater, and containerized waste are all candidates for in situ remediation. Contaminants include radioactive waste, volatile and nonvolatile organics, heavy metals, nitrates, and explosive materials.

  11. In Situ Dechlorination of TCE During Aquifer Heating

    SciTech Connect

    Truex, Michael J.; Powell, Thomas; Lynch, Kira P.

    2007-04-01

    Laboratory and field efforts were undertaken to examine trichloroethene (TCE) dechlorination as a function of temperature as an aquifer is heated to temperatures approaching boiling. Experiments were conducted using sediment samples during electrical resistance heating (ERH) treatment at the Fort Lewis East Gate Disposal Yard, which contains non-aqueous phase TCE and hydrocarbon contamination. Laboratory microcosms with these sediments showed TCE dechlorination at 70oC with measured products of acetylene, ethene, and ethane, indicating an abiotic component of the degradation. In contrast, TCE was dechlorinated to cis-1,2-dichloroethene in experiments at 10oC, likely by biological reductive dechlorination. The observed products at 70oC suggest dechlorination catalyzed by reduced sediment iron. Indications of in situ dechlorination were observed in periodic groundwater samples collected during field-scale electrical resistance heating from an average ambient temperature of about 19oC to near boiling. Dechlorination indicators included an increase in chloride concentration at the onset of heating and observation of acetylene, ethene, and methane at elevated temperatures. The data collected in this study suggest that dechlorination can occur during ERH. The overall cost-effectiveness of ERH may be enhanced by fortuitous in situ dechlorination and, potentially, can be further enhanced by specifically designing and operating ERH to maximize in situ dechlorination.

  12. In situ tensile fracture toughness of surficial cohesive marine sediments

    NASA Astrophysics Data System (ADS)

    Johnson, Bruce D.; Barry, Mark A.; Boudreau, Bernard P.; Jumars, Peter A.; Dorgan, Kelly M.

    2012-02-01

    This study reports the first in situ measurements of tensile fracture toughness, K IC, of soft, surficial, cohesive marine sediments. A newly developed probe continuously measures the stress required to cause tensile failure in sediments to depths of up to 1 m. Probe measurements are in agreement with standard laboratory methods of K IC measurements in both potter's clay and natural sediments. The data comprise in situ depth profiles from three field sites in Nova Scotia, Canada. Measured K IC at two muddy sites (median grain size of 23-50 μm) range from near zero at the sediment surface to >1,800 Pa m1/2 at 0.2 m depth. These profiles also appear to identify the bioturbated/mixed depth. K IC for a sandy site (>90% sand) is an order of magnitude lower than for the muddy sediments, and reflects the lack of cohesion/adhesion. A comparison of K IC, median grain size, and porosity in muddy sediments indicates that consolidation increases fracture strength, whereas inclusion of sand causes weakening; thus, sand-bearing layers can be easily identified in K IC profiles. K IC and vane-measured shear strength correlate strongly, which suggests that the vane measurements should perhaps be interpreted as shear fracture toughness, rather than shear strength. Comparison of in situ probe-measured values with K IC of soils and gelatin shows that sediments have a K IC range intermediate between denser compacted soils and softer, elastic gelatin.

  13. The in situ transverse lamina strength of composite laminates

    NASA Technical Reports Server (NTRS)

    Flaggs, D. L.

    1983-01-01

    The objective of the work reported in this presentation is to determine the in situ transverse strength of a lamina within a composite laminate. From a fracture mechanics standpoint, in situ strength may be viewed as constrained cracking that has been shown to be a function of both lamina thickness and the stiffness of adjacent plies that serve to constrain the cracking process. From an engineering point of view, however, constrained cracking can be perceived as an apparent increase in lamina strength. With the growing need to design more highly loaded composite structures, the concept of in situ strength may prove to be a viable means of increasing the design allowables of current and future composite material systems. A simplified one dimensional analytical model is presented that is used to predict the strain at onset of transverse cracking. While it is accurate only for the most constrained cases, the model is important in that the predicted failure strain is seen to be a function of a lamina's thickness d and of the extensional stiffness bE theta of the adjacent laminae that constrain crack propagation in the 90 deg laminae.

  14. Novel in situ chemical sensing technologies for icy environments

    NASA Astrophysics Data System (ADS)

    Wadham, Jemma; Mowlem, Matthew; Beaton, Alex; Bagshaw, Elizabeth; Lamarche-Gagnon, Guillaume; Telling, Jon; Hawkings, Jon; Tranter, Martyn

    2016-04-01

    A dramatic development in subglacial science in recent decades has been the considerable international effort aimed at improving understanding of the hidden subglacial aquatic environments beneath ice sheets. These include a diverse range of lakes, rivers, shallow and deep sediments. Technology challenges associated with the exploration of these and other icy environments are substantial because of their remote nature, extreme conditions and the requirement for sterile/clean access and sampling. In situ sensors provide an alternative to sample recovery and return for monitoring in situ conditions and are available for many analytes, but they are frequently unsuitable for deployment in icy environments. Low temperatures, freeze-thaw cycles, remote locations, low concentration and low ionic strength meltwaters challenge technologies designed for non cryospheric systems. The UK NERC- funded DELVE programme (DeEveLopment and Validation of in situ chemical sensors for icy Ecosystems) was launched with the goal of developing and testing the first suite of geochemical sensors for icy ecosystems, with a focus on redox sensitive species and dissolved nutrients. All sensors were subject to testing at low temperatures, including freeze-thaw cycling, and the response to low concentration and low ionic strength was quantified. Here we report high resolution, continuous data derived from a suite of biogeochemical sensors which were deployed to a large proglacial river draining the Greenland Ice Sheet during the 2015 melt season. These data show that these sensors have strong potential for more challenging deployment to the basal regions of ice sheets.

  15. In Situ Characterization of Nanostructures Using Rayleigh Scattering

    NASA Astrophysics Data System (ADS)

    Santra, Biswajit; Shneider, Mikhail N.; Car, Roberto

    Controlling selective growth of nanotubes has posed a considerable challenge over the last two decades. A crucial step to overcoming such hurdle is to gain detailed knowledge of the early stage of nanomaterial syntheses for which in situ measurements are required. Laser-based probes, such as Rayleigh scattering (RS), can potentially characterize the shape and size of nanoparticles in situ . The intensity of RS in a gas mixed with nanoparticles is proportional to the polarizabilities of the constituent particles, therefore, theoretical spectroscopy can complement such measurements. Here, we employed time-dependent density functional theory to compute the frequency-dependent polarizabilities of various nanostructures and predicted the corresponding RS intensity and depolarization. We found that with increasing length and asymmetry of the nanostructures the longitudinal polarizability exhibited characteristic resonances leading to measurable signatures in the RS intensity and depolarization. Also by considering gas-particle mixtures at estimated experimental conditions for nanoparticle synthesis on the periphery of an arch, we predict that in situ characterization of a few nanometer long particles with concentration as low as one particle per million is feasible using RS. This work was supported by U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

  16. Characterization of a postlavage, in situ pulmonary macrophage population.

    PubMed

    Drath, D B; Davies, P; Shorey, J M; Gibran, N S; Simpson, P J; Huber, G L

    1982-04-01

    A postlavage in situ subpopulation of pulmonary macrophages (PM), biochemically distinct from the lavaged population, has recently been isolated from rats. After exhaustive bronchopulmonary lavage to extract the free lung cells, the lungs were excised, homogenized, and filtered, and the resultant cell suspension was allowed to form a monolayer on plastic Petri dishes. Electron microscopic morphometry failed to indicate any morphologic differences in the two populations. The postlavage in situ PM were more active metabolically during phagocytosis of zymosan particles or stimulation by phorbol myristate acetate (PMA) than the corresponding lavage population, as evidenced by greater superoxide generation. Macrophages prepared by either method became more avidly phagocytic when incubated with cell-free medium isolated in the preparation of the situ population. Peroxidase, an enzyme absent from the granules of PM separated by lavage techniques, was found in a granule-rich fraction of the in situ macrophage. Catalase activity was found in similar amounts in both supernatants and granule-rich fractions of both populations. The results support the concept of subpopulations of PM and suggest that these subpopulations are distinguished by their biochemical properties and their functional abilities.

  17. Development of the integrated in situ lasagna process

    SciTech Connect

    Ho, S.; Athmer, C.; Sheridan, P.

    1995-10-01

    Contamination in deep, low permeability soils poses a significant technical challenge to in-situ remediation efforts. Poor accessibility to the contaminants and difficulty in uniform delivery of treatment reagents have rendered existing in-situ methods such as bioremediation, vapor extraction, and pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites. Recently the use of electrokinetics as an in situ method for soil remediation has received increasing attention due to its unique applicability to low-permeability soils. Electrokinetics includes the transport of water (electroosmosis) as well as ions (electromigration) as a result of an applied electric field. For remedial applications, water is typically introduced into the soil at the anode to replenish the water flowing towards the cathode due to electroosmosis. The water flow is utilized to flush organic contaminants from the subsurface soil to the ground surface at the cathode region for further treatment or disposal. This report describes a treatment process under development termed the LASAGNA process which incorporates electrokinetics, along with the establishment of degradation zones, for pollutant removal.

  18. In situ detection of anaerobic alkane metabolites in subsurface environments

    PubMed Central

    Agrawal, Akhil; Gieg, Lisa M.

    2013-01-01

    Alkanes comprise a substantial fraction of crude oil and refined fuels. As such, they are prevalent within deep subsurface fossil fuel deposits and in shallow subsurface environments such as aquifers that are contaminated with hydrocarbons. These environments are typically anaerobic, and host diverse microbial communities that can potentially use alkanes as substrates. Anaerobic alkane biodegradation has been reported to occur under nitrate-reducing, sulfate-reducing, and methanogenic conditions. Elucidating the pathways of anaerobic alkane metabolism has been of interest in order to understand how microbes can be used to remediate contaminated sites. Alkane activation primarily occurs by addition to fumarate, yielding alkylsuccinates, unique anaerobic metabolites that can be used to indicate in situ anaerobic alkane metabolism. These metabolites have been detected in hydrocarbon-contaminated shallow aquifers, offering strong evidence for intrinsic anaerobic bioremediation. Recently, studies have also revealed that alkylsuccinates are present in oil and coal seam production waters, indicating that anaerobic microbial communities can utilize alkanes in these deeper subsurface environments. In many crude oil reservoirs, the in situ anaerobic metabolism of hydrocarbons such as alkanes may be contributing to modern-day detrimental effects such as oilfield souring, or may lead to more beneficial technologies such as enhanced energy recovery from mature oilfields. In this review, we briefly describe the key metabolic pathways for anaerobic alkane (including n-alkanes, isoalkanes, and cyclic alkanes) metabolism and highlight several field reports wherein alkylsuccinates have provided evidence for anaerobic in situ alkane metabolism in shallow and deep subsurface environments. PMID:23761789

  19. Double Barrel In Situ Recanalization of Thrombosed Nonretrievable IVC filter.

    PubMed

    Banerjee, Shubhabrata; Patel, Hiten M; Sheorain, Virender K; Grover, Tarun; Parakh, Rajiv

    2016-05-01

    We report a case of endovascular recanalization of complete thrombotic occlusion of the inferior vena cava (IVC) and bilateral iliac veins using the architectural knowledge of the in situ permanent IVC filter in a 23-year-old male. The infrarenal permanent IVC filter was TRAPEASE permanent vena cava filter (Cordis) placed at an outstation hospital for pulmonary embolism. Being permanent variant of filter, percutaneous removal was not possible. The patient had severe venous claudication and an attempt to recanalize the blocked filter was considered, in view of the age no justifiable indication for a long-term filter. After pharmacomechanical catheter-directed thrombolysis, there was residual focal flow-limiting thrombus within the filter. The design of the Trapease Cordis filter was instrumental in our decision to attempt to recanalize the filter in situ using 2 parallel stents with the filter struts as anchoring pillars in a double-barrel alignment. In similar cases of persistent Trapease filter-related thrombotic occlusion of the IVC, this double barrel in situ recanalization shall be a viable alternative to the well-described technique of crushing the filter and recanalizing it with a single stent.

  20. Evolving Technologies for In-Situ Studies of Mars Ice

    NASA Technical Reports Server (NTRS)

    Carsey, F. D.; Hecht, M. H.

    2003-01-01

    Icy sites on Mars continue to be of high scientific importance. These sites include the polar caps, the southern mid-latitude subsurface permafrost, and the seasonal frost. These sites have interest due to their roles in climate processes, past climates, surface and near-surface water, astrobiology, geomorphology, and other topics. As is the case for many planetary features, remote sensing, while of great value, cannot answer all questions; in-situ examination is essential, and the motivation for in-situ observations generally leads to the subsurface, which, fortunately, is accessible on Mars. It is clear in fact that a Mars polar cap subsurface mission is both scientifically compelling and practical. Recent data from orbiting platforms has provided a remarkable level of information about the Mars ice caps; we know, for example, the size, shape and annual cycle of the cap topography as well as we know that of Earth, and we have more information on stratification that we have of, for example, the ice of East Antarctica. To understand the roles that the Mars polar caps play, it is necessary to gather information on the ice cap surface, strata, composition and bed. In this talk the status of in-situ operations and observations will be summarized, and, since we have conveniently at hand another planet with polar caps, permafrost and ice, the role of testing and validation of experimental procedures on Earth will be addressed.

  1. Automated in situ brain imaging for mapping the Drosophila connectome.

    PubMed

    Lin, Chi-Wen; Lin, Hsuan-Wen; Chiu, Mei-Tzu; Shih, Yung-Hsin; Wang, Ting-Yuan; Chang, Hsiu-Ming; Chiang, Ann-Shyn

    2015-01-01

    Mapping the connectome, a wiring diagram of the entire brain, requires large-scale imaging of numerous single neurons with diverse morphology. It is a formidable challenge to reassemble these neurons into a virtual brain and correlate their structural networks with neuronal activities, which are measured in different experiments to analyze the informational flow in the brain. Here, we report an in situ brain imaging technique called Fly Head Array Slice Tomography (FHAST), which permits the reconstruction of structural and functional data to generate an integrative connectome in Drosophila. Using FHAST, the head capsules of an array of flies can be opened with a single vibratome sectioning to expose the brains, replacing the painstaking and inconsistent brain dissection process. FHAST can reveal in situ brain neuroanatomy with minimal distortion to neuronal morphology and maintain intact neuronal connections to peripheral sensory organs. Most importantly, it enables the automated 3D imaging of 100 intact fly brains in each experiment. The established head model with in situ brain neuroanatomy allows functional data to be accurately registered and associated with 3D images of single neurons. These integrative data can then be shared, searched, visualized, and analyzed for understanding how brain-wide activities in different neurons within the same circuit function together to control complex behaviors.

  2. The in situ saphenous vein bypass graft: radiologic aspects.

    PubMed

    Schwarz, W; Nozick, J; Richmand, D; Rodgers, B; Simpson, A; Argila, C; Honickman, S

    1986-03-01

    The use of the in situ saphenous vein for bypassing arterial occlusions in the lower extremities appears to have a higher patency rate than other bypass procedures but presents unique technical problems, such as lysing valves and occluding venous tributaries. Forty-four patients undergoing in situ bypasses had preoperative arteriograms. Special attention was paid to the small runoff vessels around the ankle, which are not suitable for reversed bypass procedures but may be adequate for in situ bypasses. Eight patients also had preoperative saphenous venograms, which revealed surgically important abnormalities in six cases. Postoperative arteriograms obtained within 2 weeks in 10 patients and within 2-12 months in 15 patients revealed persistent arteriovenous fistulas in four patients, stenoses in nine, occlusions in five, and progressive disease in the nonbypassed arteries in five patients. Early recognition of these problems led to 11 surgical repairs; nine repairs used the interventional radiologic procedures of balloon angioplasty, transcatheter embolization, and catheter thrombolysis. In this group of 44 patients, five patients died with patent bypasses and three patients required amputation despite functioning bypasses. Only four amputations were attributed to bypass failure. This low figure may be due to the close cooperation of the vascular surgeons and the vascular radiologists in dealing with these complicated cases.

  3. In situ detection of anaerobic alkane metabolites in subsurface environments.

    PubMed

    Agrawal, Akhil; Gieg, Lisa M

    2013-01-01

    Alkanes comprise a substantial fraction of crude oil and refined fuels. As such, they are prevalent within deep subsurface fossil fuel deposits and in shallow subsurface environments such as aquifers that are contaminated with hydrocarbons. These environments are typically anaerobic, and host diverse microbial communities that can potentially use alkanes as substrates. Anaerobic alkane biodegradation has been reported to occur under nitrate-reducing, sulfate-reducing, and methanogenic conditions. Elucidating the pathways of anaerobic alkane metabolism has been of interest in order to understand how microbes can be used to remediate contaminated sites. Alkane activation primarily occurs by addition to fumarate, yielding alkylsuccinates, unique anaerobic metabolites that can be used to indicate in situ anaerobic alkane metabolism. These metabolites have been detected in hydrocarbon-contaminated shallow aquifers, offering strong evidence for intrinsic anaerobic bioremediation. Recently, studies have also revealed that alkylsuccinates are present in oil and coal seam production waters, indicating that anaerobic microbial communities can utilize alkanes in these deeper subsurface environments. In many crude oil reservoirs, the in situ anaerobic metabolism of hydrocarbons such as alkanes may be contributing to modern-day detrimental effects such as oilfield souring, or may lead to more beneficial technologies such as enhanced energy recovery from mature oilfields. In this review, we briefly describe the key metabolic pathways for anaerobic alkane (including n-alkanes, isoalkanes, and cyclic alkanes) metabolism and highlight several field reports wherein alkylsuccinates have provided evidence for anaerobic in situ alkane metabolism in shallow and deep subsurface environments.

  4. In situ click chemistry generation of cyclooxygenase-2 inhibitors.

    PubMed

    Bhardwaj, Atul; Kaur, Jatinder; Wuest, Melinda; Wuest, Frank

    2017-12-01

    Cyclooxygenase-2 isozyme is a promising anti-inflammatory drug target, and overexpression of this enzyme is also associated with several cancers and neurodegenerative diseases. The amino-acid sequence and structural similarity between inducible cyclooxygenase-2 and housekeeping cyclooxygenase-1 isoforms present a significant challenge to design selective cyclooxygenase-2 inhibitors. Herein, we describe the use of the cyclooxygenase-2 active site as a reaction vessel for the in situ generation of its own highly specific inhibitors. Multi-component competitive-binding studies confirmed that the cyclooxygenase-2 isozyme can judiciously select most appropriate chemical building blocks from a pool of chemicals to build its own highly potent inhibitor. Herein, with the use of kinetic target-guided synthesis, also termed as in situ click chemistry, we describe the discovery of two highly potent and selective cyclooxygenase-2 isozyme inhibitors. The in vivo anti-inflammatory activity of these two novel small molecules is significantly higher than that of widely used selective cyclooxygenase-2 inhibitors.Traditional inflammation and pain relief drugs target both cyclooxygenase 1 and 2 (COX-1 and COX-2), causing severe side effects. Here, the authors use in situ click chemistry to develop COX-2 specific inhibitors with high in vivo anti-inflammatory activity.

  5. Time-resolved Raman spectroscopy for in situ planetary mineralogy.

    PubMed

    Blacksberg, Jordana; Rossman, George R; Gleckler, Anthony

    2010-09-10

    Planetary mineralogy can be revealed through a variety of remote sensing and in situ investigations that precede any plans for eventual sample return. We briefly review those techniques and focus on the capabilities for on-surface in situ examination of Mars, Venus, the Moon, asteroids, and other bodies. Over the past decade, Raman spectroscopy has continued to develop as a prime candidate for the next generation of in situ planetary instruments, as it provides definitive structural and compositional information of minerals in their natural geological context. Traditional continuous-wave Raman spectroscopy using a green laser suffers from fluorescence interference, which can be large (sometimes saturating the detector), particularly in altered minerals, which are of the greatest geophysical interest. Taking advantage of the fact that fluorescence occurs at a later time than the instantaneous Raman signal, we have developed a time-resolved Raman spectrometer that uses a streak camera and pulsed miniature microchip laser to provide picosecond time resolution. Our ability to observe the complete time evolution of Raman and fluorescence spectra in minerals makes this technique ideal for exploration of diverse planetary environments, some of which are expected to contain strong, if not overwhelming, fluorescence signatures. We discuss performance capability and present time-resolved pulsed Raman spectra collected from several highly fluorescent and Mars-relevant minerals. In particular, we have found that conventional Raman spectra from fine grained clays, sulfates, and phosphates exhibited large fluorescent signatures, but high quality spectra could be obtained using our time-resolved approach.

  6. In situ quantitative imaging of cellular lipids using molecular sensors

    NASA Astrophysics Data System (ADS)

    Yoon, Youngdae; Lee, Park J.; Kurilova, Svetlana; Cho, Wonhwa

    2011-11-01

    Membrane lipids are dynamic molecules that play important roles in cell signalling and regulation, but an in situ imaging method for quantitatively tracking lipids in living cells is lacking at present. Here, we report a new chemical method of quantitative lipid imaging using sensors engineered by labelling proteins with an environmentally sensitive fluorophore. A prototype sensor for phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2)—a key signalling lipid in diverse cellular processes—was generated by covalently attaching a single 2-dimethylamino-6-acyl-naphthalene group to the N-terminal α-helix of the engineered epsin1 ENTH domain, a protein that selectively binds PtdIns(4,5)P2. The sensor allows robust and sensitive in situ quantitative imaging in mammalian cells, providing new insight into the spatiotemporal dynamics and fluctuation of this key signalling lipid. Application of the sensor to immune cells reveals the presence of a local threshold PtdIns(4,5)P2 concentration required for triggering phagocytosis. This sensor strategy is generally applicable to in situ quantification of other cellular lipids.

  7. Damage and in-situ annealing during ion implantation

    SciTech Connect

    Sadana, D.K.; Washburn, J.; Byrne, P.F.; Cheung, N.W.

    1982-11-01

    Formation of amorphous (..cap alpha..) layers in Si during ion implantation in the energy range 100 keV-11 MeV and temperature range liquid nitrogen (LN)-100/sup 0/C has been investigated. Cross-sectional transmission electron microscopy (XTEM) shows that buried amorphous layers can be created for both room temperature (RT) and LN temperature implants, with a wider 100 percent amorphous region for the LN cooled case. The relative narrowing of the ..cap alpha.. layer during RT implantation is attributed to in-situ annealing. Implantation to the same fluence at temperatures above 100/sup 0/C does not produce ..cap alpha.. layers. To further investigate in situ annealing effects, specimens already containing buried ..cap alpha.. layers were further irradiated with ion beams in the temperature range RT-400/sup 0/C. It was found that isolated small ..cap alpha.. zones (less than or equal to 50 diameter) embedded in the crystalline matrix near the two ..cap alpha../c interfaces dissolved into the crystal but the thickness of the 100 percent ..cap alpha.. layer was not appreciably affected by further implantation at 200/sup 0/C. A model for in situ annealing during implantation is presented.

  8. In-situ propellant advantages for fast transfer to Mars

    NASA Technical Reports Server (NTRS)

    Galecki, Diane L.

    1988-01-01

    The advantages of in situ propellant for a fast transfer to Mars were studied as compared to all earth-based propellants and other options for reduction of total masss in low earth orbit. For a 10-year, 10-mission model and a baseline vehicle taken from the literature, the total reduction in number of earth launches was calculated. The scenario in which the return propellants are transferred to Mars on a slow cargo vehicle provides a 29-percent reduction in ALS launches over the baseline scenario in which all propellants are brought directly from earth. The scenarios in which in situ propellants are used for a successively greater portion of the total mission continue to reduce the number of launches required. With Mars propellant used for the Mars ascent vehicle and the return leg of the mission, a 59-percent reduction in launches is obtained. Finally, if the oxygen, or oxygen and fuel, for the outbound leg of the mission is also obtained by in situ production, from the moon for example, then the total reduction in number of earth launches is more than 80 percent.

  9. Technologies for in situ cleanup of contaminated sites.

    PubMed

    Udell, K S; Grubb, D G; Sitar, N

    1995-05-01

    Groundwater contamination by non-aqueous phase liquids (NAPLs) and denser than water non-aqueous phase liquids (DNAPLs) poses one of the greatest remedial challenges in the field of environmental engineering. Due to low water solubilities and aqueous diffusivities, conventional pump-and-treat technologies have a poor record of success in remediation of DNAPL contaminated aquifers. Better success has been found with the removal of volatile LNAPLs due to higher gaseous diffusivities, propensity for aerobic biodegradation, and ease of pumping and handling large quantities of gas. An evaluation of in situ cleanup technologies on the basis of their applicability to in situ treatment of NAPL contaminated aquifers is presented. Emphasis is placed on treatment of the separate phase occurring in the saturated zone. Soil washing, air sparging, biodegradation, electro-osmosis, enhanced steam extraction, stabilization/solidification, treatment walls, radio frequency heating, and containment systems and barriers are among the in situ technologies reviewed. In the context of the governing contaminant fate and transport processes, the relative merits of each technology are assessed on the basis of its theoretical background, field implementability, level of demonstration and performance, waste, technical and site applicability/limitations, commercial availability, and cost and residuals management.

  10. Combining Remote Sensing with in situ Measurements for Riverine Characterization

    NASA Astrophysics Data System (ADS)

    Calantoni, J.; Palmsten, M. L.; Simeonov, J.; Dobson, D. W.; Zarske, K.; Puleo, J. A.; Holland, K. T.

    2014-12-01

    At the U.S. Naval Research Laboratory we are employing a wide variety of novel remote sensing techniques combined with traditional in situ sampling to characterize riverine hydrodynamics and morphodynamics. Surface currents were estimated from particle image velocimetry (PIV) using imagery from visible to infrared bands, from both fixed and airborne platforms. Terrestrial LIDAR has been used for subaerial mapping from a fixed platform. Additionally, LIDAR has been combined with hydrographic surveying (multibeam) in mobile scanning mode using a small boat. Hydrographic surveying (side scan) has also been performed using underwater autonomous vehicles. Surface drifters have been deployed in combination with a remotely operated, floating acoustic Doppler current profiler. Other fixed platform, in situ sensors, such as pencil beam and sector scanning sonars, acoustic Doppler velocimeters, and water level sensors have been deployed. We will present an overview of a variety of measurements from different rivers around the world focusing on validation examples of remotely sensed quantities with more traditional in situ measurements. Finally, we will discuss long-term goals to use remotely sensed data within an integrated environmental modeling framework.

  11. In Situ Measurement of Tritium Permeation Through Stainless Steel

    SciTech Connect

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin; Longhurst, Glen

    2013-06-01

    The TMIST-2 irradiation experiment was conducted in the Advanced Test Reactor at Idaho National Laboratory to evaluate tritium permeation through Type 316 stainless steel (316 SS). The interior of a 316 SS seamless tube specimen was exposed to a 4He carrier gas mixed with a specified quantity of tritium (T2) to yield partial pressures of 0.1, 5, and 50 Pa at 292° and 330°C. In-situ tritium permeation measurements were made by passing a He-Ne sweep gas over the outer surface of the specimen to carry the permeated tritium to a bubbler column for liquid scintillation counting. An irradiation enhancement factor (IEF) was determined by comparing in-situ permeation data with a correlation for ex-reactor hydrogen permeation through austenitic stainless steel developed from literature data and reported by Le Claire. Nominal values for the IEF ranged between 3 and 5 for 316 SS. In-situ permeation data were also used to derive an in-reactor permeation correlation as a function of temperature and pressure. In addition, the triton recoil contribution to tritium permeation, which results from the transmutation of 3He to T, was also evaluated by introducing a 4He carrier gas mixed with 3He at a partial pressure of 1013 Pa at 330°C. Less than 3% of the tritium resulting from 3He transmutation contributed to tritium permeation.

  12. IN-SITU MEASUREMENT OF TRITIUM PERMEATION THROUGH STAINLESS STEEL

    SciTech Connect

    Luscher, Walter G.; Senor, David J.; Clayton, Kevin; Longhurst, Glen R.

    2013-06-01

    The TMIST-2 irradiation experiment was conducted in the Advanced Test Reactor at Idaho National Laboratory to evaluate tritium permeation through Type 316 stainless steel (316 SS). The interior of a 316 SS seamless tube specimen was exposed to a 4He carrier gas mixed with a specified quantity of tritium (T2) to yield partial pressures of 0.1, 5, and 50 Pa at 292° and 330°C. In-situ tritium permeation measurements were made by passing a He-Ne sweep gas over the outer surface of the specimen to carry the permeated tritium to a bubbler column for liquid scintillation counting. An irradiation enhancement factor (IEF) was determined by comparing in-situ permeation data with a correlation for ex-reactor hydrogen permeation through austenitic stainless steel developed from literature data and reported by Le Claire. Nominal values for the IEF ranged between 3 and 5 for 316 SS. In-situ permeation data were also used to derive an in-reactor permeation correlation as a function of temperature and pressure. In addition, the triton recoil contribution to tritium permeation, which results from the transmutation of 3He to T, was also evaluated by introducing a 4He carrier gas mixed with 3He at a partial pressure of 1013 Pa at 330°C. Less than 3% of the tritium resulting from 3He transmutation contributed to tritium permeation.

  13. In situ measurement of tritium permeation through stainless steel

    SciTech Connect

    Walter G. Luscher; David J. Senor; Kevin K. Clayton; Glen R. Longhurst

    2013-06-01

    The TMIST-2 irradiation experiment was conducted in the Advanced Test Reactor at Idaho National Laboratory to evaluate tritium permeation through Type 316 stainless steel (316 SS). The interior of a 316 SS seamless tube specimen was exposed to a 4He carrier gas mixed with a specified quantity of tritium (T2) to yield partial pressures of 0.1, 5, and 50 Pa at 292 degrees C and 330 degrees C. In situ tritium permeation measurements were made by passing a He-Ne sweep gas over the outer surface of the specimen to carry the permeated tritium to a bubbler column for liquid scintillation counting. Results from in situ permeation measurements were compared with predictions based on an ex-reactor permeation correlation in the literature. In situ permeation data were also used to derive an in-reactor permeation correlation as a function of temperature and pressure over the ranges considered in this study. In addition, the triton recoil contribution to tritium permeation, which results from the transmutation of 3He to T, was also evaluated by introducing a 4He carrier gas mixed with 3He at a partial pressure of 1013 Pa at 330 degrees C. Less than 3% of the tritium resulting from 3He transmutation contributed to tritium permeation.

  14. Aquifer restoration at uranium in situ leach sites

    NASA Astrophysics Data System (ADS)

    Anastasi, Frank S.; Williams, Roy E.

    1984-12-01

    In situ mining of uranium involves injection of a leaching solution (lixiviant) into an ore-bearing aquifer. Frequently, the ground water in the mined aquifer is a domestic or livestock water supply. As the lixiviant migrates through the ore body, uranium and various associated elements such as arsenic, selenium, molybdenum, vanadium and radium-226 are mobilized in the ground water. Aquifer restoration after in situ mining is not fully understood. Several methods have been developed to restore mined aquifers to pre-mining (baseline) quality. Commonly used methods include ground water sweeping, clean water injection, and treatment by ion exchange and reverse osmosis technologies. Ammonium carbonate lixiviant was used at one R&D in situ mine. Attempts were made to restore the aquifer using a variety of methods. Efforts were successful in reducing concentrations of the majority of contaminants to baseline levels. Concentrations of certain parameters, however, remained at levels above baseline six months after restoration ceased. Relatively large quantitites of ground water were processed in the restoration attempt considering the small size of the project (1.25 acre). More thorough characterization of the hydrogeology of the site may have enhanced the effectiveness of restoration and reduced potential environmental impacts associated with the project. This paper presents some of the findings of a research project conducted by the Mineral Resources Waste Management Team at the University of Idaho in Moscow, Idaho. Views contained herein do not reflect U.S. Nuclear Regulatory Commission policy.

  15. Biofouling: A critical consideration for evaluating in situ biotreatment feasibility

    SciTech Connect

    Kaufman, K.A.

    1995-09-01

    It is recognized by the EPA and many state and local regulatory agencies that in situ bioremedial treatment can be a technically sound and highly cost-effective method for the mitigation of soil and groundwater contamination, and numerous case histories corroborate this belief. Though not widely publicized (for understandable reasons), notable failures of similar treatment attempts can be traced to the consequences of biofouling, resultant from the inappropriate use of in situ treatment technologies. Such consequences can be related to the development of anaerobiosis due to inadequate diffusion of bioavailable oxygen to allow for aerobic metabolism within the contaminated soil matrix. Appropriate engineering and hydrogeological considerations of a site`s compatibility with in situ treatment requirements prior to process initiation can preclude the potential for the generation of noxious and/or toxic/explosive gases, as well as toxic endproducts of anaerobic microbial metabolism. Appropriate utilization of hydrogen peroxide, taking into account for the requirement for the enzyme catalase, and the biotoxic nature of hydrogen peroxide to many microorganisms, can minimize the deleterious effects of anaerobiosis and enhance oxidative bioremedial activity.

  16. In-situ propellant advantages for fast transfer to Mars

    NASA Technical Reports Server (NTRS)

    Galecki, Diane L.

    1988-01-01

    The advantages of in situ propellant for a fast transfer to Mars were studied as compared to all earth-based propellants and other options for reduction of total masss in low earth orbit. For a 10-year, 10-mission model and a baseline vehicle taken from the literature, the total reduction in number of earth launches was calculated. The scenario in which the return propellants are transferred to Mars on a slow cargo vehicle provides a 29-percent reduction in ALS launches over the baseline scenario in which all propellants are brought directly from earth. The scenarios in which in situ propellants are used for a successively greater portion of the total mission continue to reduce the number of launches required. With Mars propellant used for the Mars ascent vehicle and the return leg of the mission, a 59-percent reduction in launches is obtained. Finally, if the oxygen, or oxygen and fuel, for the outbound leg of the mission is also obtained by in situ production, from the moon for example, then the total reduction in number of earth launches is more than 80 percent.

  17. In situ structural analysis of the Yersinia enterocolitica injectisome

    PubMed Central

    Kudryashev, Mikhail; Stenta, Marco; Schmelz, Stefan; Amstutz, Marlise; Wiesand, Ulrich; Castaño-Díez, Daniel; Degiacomi, Matteo T; Münnich, Stefan; Bleck, Christopher KE; Kowal, Julia; Diepold, Andreas; Heinz, Dirk W; Dal Peraro, Matteo; Cornelis, Guy R; Stahlberg, Henning

    2013-01-01

    Injectisomes are multi-protein transmembrane machines allowing pathogenic bacteria to inject effector proteins into eukaryotic host cells, a process called type III secretion. Here we present the first three-dimensional structure of Yersinia enterocolitica and Shigella flexneri injectisomes in situ and the first structural analysis of the Yersinia injectisome. Unexpectedly, basal bodies of injectisomes inside the bacterial cells showed length variations of 20%. The in situ structures of the Y. enterocolitica and S. flexneri injectisomes had similar dimensions and were significantly longer than the isolated structures of related injectisomes. The crystal structure of the inner membrane injectisome component YscD appeared elongated compared to a homologous protein, and molecular dynamics simulations documented its elongation elasticity. The ring-shaped secretin YscC at the outer membrane was stretched by 30–40% in situ, compared to its isolated liposome-embedded conformation. We suggest that elasticity is critical for some two-membrane spanning protein complexes to cope with variations in the intermembrane distance. DOI: http://dx.doi.org/10.7554/eLife.00792.001 PMID:23908767

  18. In situ aerobic cometabolism of chlorinated solvents: a review.

    PubMed

    Frascari, Dario; Zanaroli, Giulio; Danko, Anthony S

    2015-01-01

    The possible approaches for in situ aerobic cometabolism of aquifers and vadose zones contaminated by chlorinated solvents are critically evaluated. Bioaugmentation of resting-cells previously grown in a fermenter and in-well addition of oxygen and growth substrate appear to be the most promising approaches for aquifer bioremediation. Other solutions involving the sparging of air lead to satisfactory pollutant removals, but must be integrated by the extraction and subsequent treatment of vapors to avoid the dispersion of volatile chlorinated solvents in the atmosphere. Cometabolic bioventing is the only possible approach for the aerobic cometabolic bioremediation of the vadose zone. The examined studies indicate that in situ aerobic cometabolism leads to the biodegradation of a wide range of chlorinated solvents within remediation times that vary between 1 and 17 months. Numerous studies include a simulation of the experimental field data. The modeling of the process attained a high reliability, and represents a crucial tool for the elaboration of field data obtained in pilot tests and for the design of the full-scale systems. Further research is needed to attain higher concentrations of chlorinated solvent degrading microbes and more reliable cost estimates. Lastly, a procedure for the design of full-scale in situ aerobic cometabolic bioremediation processes is proposed.

  19. Effects of temperature on in situ toxicity testing

    SciTech Connect

    Rowland, C.D.; Burton, G.A. Jr.

    1994-12-31

    With increasing concern over the impacts and perturbations to receiving waters as a result of storm water runoff and contaminated sediments, many investigators have turned towards in situ testing for direct response data. In situ testing has been shown to be an effective assessment tool. In order to further evaluate the limitations of this method, temperature effects were evaluated. There is concern that laboratory to stream transfer of test organisms may induce significant stress if water temperatures are too cool. This study was designed to specifically address the issue of temperature tolerance and attenuation of Hyalella azteca, Ceriodaphnia dubia and Pimephales promelas in in situ conditions. Temperature tolerance is of importance in areas where receiving waters are subject to low or fluctuating temperatures as well as areas of more temperate climates. In this study, the organisms where exposed to temperatures as low as 2 C for variable lengths of time, removed and allowed to come to ambient laboratory temperatures then monitored for acute or chronic responses. No effects on survival were observed after 48 h. at 5 C; however lower temperatures increased mortality.

  20. Generating CO(2)-credits through landfill in situ aeration.

    PubMed

    Ritzkowski, M; Stegmann, R

    2010-04-01

    Landfills are some of the major anthropogenic sources of methane emissions worldwide. The installation and operation of gas extraction systems for many landfills in Europe and the US, often including technical installations for energy recovery, significantly reduced these emissions during the last decades. Residual landfill gas, however, is still continuously produced after the energy recovery became economically unattractive, thus resulting in ongoing methane emissions for many years. By landfill in situ aeration these methane emissions can be widely avoided both, during the aeration process as well as in the subsequent aftercare period. Based on model calculations and online monitoring data the amount of avoided CO(2-eq). can be determined. For an in situ aerated landfill in northern Germany, acting as a case study, 83-95% (depending on the kind and quality of top cover) of the greenhouse gas emission potential could be reduced under strictly controlled conditions. Recently the United Nations Framework Convention on Climate Change (UNFCCC) has approved a new methodology on the "Avoidance of landfill gas emissions by in situ aeration of landfills" (UNFCCC, 2009). Based on this methodology landfill aeration projects might be considered for generation of Certified Emission Reductions (CERs) in the course of CDM projects. This paper contributes towards an evaluation of the potential of landfill aeration for methane emissions reduction. Copyright 2009 Elsevier Ltd. All rights reserved.