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Sample records for mono diameter wellbore

  1. Experimental determination of wellbore diameter and shape (4D imaging of wellbore) by using ultrasonic caliper within different fluids for real-time drilling application

    Energy Technology Data Exchange (ETDEWEB)

    Elahifar, Behzad; Esmaeili, Abdolali; Thonhauser, Gerhard [Montanuniversitaet Leoben (Austria); Fruhwirth, Rudolf K. [TDE Thonhauser Data Engineering GmbH, Leoben (Austria)

    2013-03-15

    Drilling programs continue to push into new and more complicated environments. As a result, accurate measurement, interpretation and analysis of drilling data in real time are becoming more critical. One of the key measurement devices for drilling, cementing and formation evaluation is the borehole caliper. An ultrasonic sensor caliper tool is thereby a key measurement device for determining the borehole diameter in MWD or LWD tools. Another use of ultrasonic caliper tools is to offer a method for calculating borehole volumes. Real-time application of ultrasonic caliper tools can also support the early detection of borehole instability. This paper describes the experiments related to the accuracy of the ultrasonic sensor for measuring wellbore diameter by performing the tests in different fluids, comparing the results and determining the weak points of the sensor for detecting echoes. In addition the wellbore profiles were simulated and the simulated results were compared with the recorded data. Different tests related to the position of the caliper tool inside the wellbore were performed as well as the evaluation of the accuracy of the ultrasonic sensor by simulating dog-legs and latches. (orig.)

  2. Large Diameter Freeze Shaft Single Wellbore Grouting Plugging Technology Research%大直径冻结井筒单层井壁注浆堵水技术研究

    Institute of Scientific and Technical Information of China (English)

    陈德明; 段安新

    2014-01-01

    To study the freezing of large diameter single wellbore wall grouting technology for large amount of leakage problems wellbore door grams celebrate mine shaft began to thaw vice combining technical features wellbore wall hydrogeological conditions and parameters of the wellbore after the walls ,curtains and wall impermeable microcracks take phased ,focused carried grouting .The results show that:the amount of leakage from the wellbore 233 m3/h reduced to 4.5 m3/h,reaching the amount of wellbore leakage specifications .%为研究大直径冻结井筒单层井壁注浆堵水技术,针对门克庆矿副立井开始解冻后井筒漏水量较大的问题,结合井筒的技术特征、水文地质情况和井壁参数,对井筒壁后、隔水帷幕及井壁微裂纹采取分阶段、分重点进行注浆堵水。结果表明:井筒漏水量由233 m3/h降低为4.5 m3/h,达到井筒漏水量规范要求。

  3. Wellbore Integrity Network

    Energy Technology Data Exchange (ETDEWEB)

    Carey, James W. [Los Alamos National Laboratory; Bachu, Stefan [Alberta Innovates

    2012-06-21

    In this presentation, we review the current state of knowledge on wellbore integrity as developed in the IEA Greenhouse Gas Programme's Wellbore Integrity Network. Wells are one of the primary risks to the successful implementation of CO{sub 2} storage programs. Experimental studies show that wellbore materials react with CO{sub 2} (carbonation of cement and corrosion of steel) but the impact on zonal isolation is unclear. Field studies of wells in CO{sub 2}-bearing fields show that CO{sub 2} does migrate external to casing. However, rates and amounts of CO{sub 2} have not been quantified. At the decade time scale, wellbore integrity is driven by construction quality and geomechanical processes. Over longer time-scales (> 100 years), chemical processes (cement degradation and corrosion) become more important, but competing geomechanical processes may preserve wellbore integrity.

  4. Wellbore pressure transducer

    Science.gov (United States)

    Shuck, Lowell Z.

    1979-01-01

    Subterranean earth formations containing energy values are subjected to hydraulic fracturing procedures to enhance the recovery of the energy values. These fractures are induced in the earth formation by pumping liquid into the wellbore penetrating the earth formation until the pressure of the liquid is sufficient to fracture the earth formation adjacent to the wellbore. The present invention is directed to a transducer which is positionable within the wellbore to generate a signal indicative of the fracture initiation useful for providing a timing signal to equipment for seismic mapping of the fracture as it occurs and for providing a measurement of the pressure at which the fracture is initiated.

  5. What's Mono?

    Science.gov (United States)

    ... es mono? Have you ever heard of the "kissing disease"? If you said that it's mono, you' ... But you don't get mono only from kissing. Infectious mononucleosis, called mono for short, is caused ...

  6. Rate Gyroscopic Wellbore Survey System

    Institute of Scientific and Technical Information of China (English)

    Sheng Limin

    1997-01-01

    @@ The rate gyroscopic wellbore survey system as a new type of survey instruments adopts the inertial-grade rate gyro and quartz flexible accelerometers to compose a gyrocompassing system, transiting data to surface instrument by single core cable. The azimuth, inclination and tool-face angle can be computed from these data by surface computer.

  7. Heating production fluids in a wellbore

    Science.gov (United States)

    Orrego, Yamila; Jankowski, Todd A.

    2016-07-12

    A method for heating a production fluid in a wellbore. The method can include heating, using a packer fluid, a working fluid flowing through a first medium disposed in a first section of the wellbore, where the first medium transfers heat from the packer fluid to the working fluid. The method can also include circulating the working fluid into a second section of the wellbore through a second medium, where the second medium transfers heat from the working fluid to the production fluid. The method can further include returning the working fluid to the first section of the wellbore through the first medium.

  8. Drilling subsurface wellbores with cutting structures

    Science.gov (United States)

    Mansure, Arthur James; Guimerans, Rosalvina Ramona

    2010-11-30

    A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

  9. High-energy gas fracturing in cased and perforated wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Cuderman, J.F.

    1986-06-01

    A propellant-based technology, High-Energy Gas Fracturing (HEGF), has been applied to fracturing through perforations in cased boreholes. HEGF is a tailored-pulse fracturing technique originally developed by Sandia National Laboratories for application in uncased, liquid-free gas wells in Appalachian Devonian shales. Because most oil and gas wells are liquid filled as well as cased and perforated, the potential impact of present research is significantly broader. A number of commercial tailored-pulse fracturing services, using a variety of explosives or propellants, are currently available. Present research provides valuable insight into phenomena that occur in those stimulations. The use of propellants that deflagrate or burn rather than detonate, as do high-order explosives, permits controlled buildup of pressure in the wellbore. The key to successful stimulation in cased and perforated wellbores is to control the pressure buildup of the combustion gases to maximize fracturing without destroying the casing. Eight experiments using cased and perforated wellbore were conducted in a tunnel complex at the Department of Energy's Nevada Test Site, which provides a realistic in situ stress environment (4 to 10 MPa (600 to 1500 psi)) and provides access for mineback to directly observe fracturing obtained. Primary variables in the experiments include propellant burn rate and amount of propellant used, presence or absence of liquid in the wellbore, in situ stress orientation, and perforation diameter, density, and phasing. In general, the presence of liquid in the borehole results in a much faster pressure risetime and a lower peak pressure for the same propellant charge. Fracture surfaces proceed outward along lines of perforations as determined by phasing, then gradually turn toward the hydraulic fracture direction. 8 refs., 23 figs., 3 tabs.

  10. Quantifying drag on wellbore casings in moving salt sheets

    Science.gov (United States)

    Weijermars, R.; Jackson, M. P. A.; Dooley, T. P.

    2014-08-01

    Frontier hydrocarbon development projects in the deepwater slopes of the Gulf of Mexico Basin, Santos Basin and Lower Congo Basin all require wells to cross ductile layers of autochthonous or allochthonous salt moving at peak rates of 100 mm yr-1. The Couette-Poiseuille number is introduced here to help pinpoint the depth of shear stress reversal in such salt layers. For any well-planned through salt, the probable range of creep forces of moving salt needs to be taken into account when designing safety margins and load-factor tolerance of the well casing. Drag forces increase with wellbore diameter, but more significantly with effective viscosity and speed of the creeping salt layer. The potential drag forces on cased wellbores in moving salt sheets are estimated analytically using a range of salt viscosities (1015-1019 Pa s) and creep rates (0-10 mm yr-1). Drag on perfectly rigid casing of infinite strength may reach up to 13 Giga Newton per meter wellbore length in salt having a viscosity of 1019 Pa s. Well designers may delay stress accumulations due to salt drag when flexible casing accommodates some of the early displacement and strain. However, all creeping salt could displace, fracture and disconnect well casing, eventually. The shear strength of typical heavy duty well casing (about 1000 MPa) can be reached due to drag by moving salt. Internal flow of salt will then fracture the casing near salt entry and exit points, but the structural damage is likely to remain unnoticed early in the well-life when the horizontal shift of the wellbore is still negligibly small (at less than 1 cm yr-1). Disruption of casing and production flow lines within the anticipated service lifetime of a well remains a significant risk factor within distinct zones of low-viscosity salt which may reach ultrafast creep rates of 100 mm yr-1.

  11. Wellbore Seal Repair Using Nanocomposite Materials

    Energy Technology Data Exchange (ETDEWEB)

    Stormont, John [Univ. of New Mexico, Albuquerque, NM (United States)

    2016-08-31

    Nanocomposite wellbore repair materials have been developed, tested, and modeled through an integrated program of laboratory testing and numerical modeling. Numerous polymer-cement nanocomposites were synthesized as candidate wellbore repair materials using various combinations of base polymers and nanoparticles. Based on tests of bond strength to steel and cement, ductility, stability, flowability, and penetrability in opening of 50 microns and less, we identified Novolac epoxy reinforced with multi-walled carbon nanotubes and/or alumina nanoparticles to be a superior wellbore seal material compared to conventional microfine cements. A system was developed for testing damaged and repaired wellbore specimens comprised of a cement sheath cast on a steel casing. The system allows independent application of confining pressures and casing pressures while gas flow is measured through the specimens along the wellbore axis. Repair with the nanocomposite epoxy base material was successful in dramatically reducing the flow through flaws of various sizes and types, and restoring the specimen comparable to an intact condition. In contrast, repair of damaged specimens with microfine cement was less effective, and the repair degraded with application of stress. Post-test observations confirm the complete penetration and sealing of flaws using the nanocomposite epoxy base material. A number of modeling efforts have supported the material development and testing efforts. We have modeled the steel-repair material interface behavior in detail during slant shear tests, which we used to characterize bond strength of candidate repair materials. A numerical model of the laboratory testing of damaged wellbore specimens was developed. This investigation found that microannulus permeability can satisfactorily be described by a joint model. Finally, a wellbore model has been developed that can be used to evaluate the response of the wellbore system (casing, cement, and microannulus

  12. Wellbore enlargement investigation: Potential analogs to the Waste Isolation Pilot Plant during inadvertent intrusion of the repository

    Energy Technology Data Exchange (ETDEWEB)

    Boak, D.M.; Dotson, L.; Aguilar, R. [and others

    1997-01-01

    This study involved the evaluation and documentation of cases in which petroleum wellbores were enlarged beyond the nominal hole diameter as a consequence of erosion during exploratory drilling, particularly as a function of gas flow into the wellbore during blowout conditions. A primary objective was to identify analogs to potential wellbore enlargement at the Waste Isolation Pilot Plant (WIPP) during inadvertent human intrusion. Secondary objectives were to identify drilling scenarios associated with enlargement, determine the physical extent of enlargement, and establish the physical properties of the formation in which the enlargement occurred. No analogs of sufficient quality to establish quantitative limits on wellbore enlargement at the WIPP disposal system were identified. However, some information was obtained regarding the frequency of petroleum well blowouts and the likelihood that such blowouts would bridge downhole, self-limiting the surface release of disposal-system material. Further work would be necessary, however, to determine the conditions under which bridging could occur and the extent to which the bridging might be applicable to WIPP. In addition, data on casing sizes of petroleum boreholes in the WIPP vicinity support the use of a 12-{1/4} inch borehole size in WIPP performance assessment calculations. Finally, although data are limited, there was no evidence of significant wellbore enlargement in any of three blowouts that occur-red in wellbores in the Delaware Basin (South Culebra Bluff Unit No. 1, Energy Research and Development Administration (ERDA) 6, and WIPP 12).

  13. Proceedings of the wellbore sampling workshop

    Energy Technology Data Exchange (ETDEWEB)

    Traeger, R.K. (ed.); Harding, B.W.

    1987-11-01

    Representatives from academia, industry and research laboratories participated in an intensive two-day review to identify major technological limitations in obtaining solid and fluid samples from wellbores. Top priorities identified for further development include: coring of hard and unconsolidated materials; flow through fluid samplers with borehole measurements T, P and pH; and nonintrusive interrogation of pressure cores.

  14. Geomechanics of fracture caging in wellbores

    NARCIS (Netherlands)

    Weijermars, R.; Zhang, X.; Schultz-Ela, D.

    2013-01-01

    This study highlights the occurrence of so-called ‘fracture cages’ around underbalanced wellbores, where fractures cannot propagate outwards due to unfavourable principal stress orientations. The existence of such cages is demonstrated here by independent analytical and numerical methods. We explain

  15. Geomechanics of fracture caging in wellbores

    NARCIS (Netherlands)

    Weijermars, R.; Zhang, X.; Schultz-Ela, D.

    2013-01-01

    This study highlights the occurrence of so-called ‘fracture cages’ around underbalanced wellbores, where fractures cannot propagate outwards due to unfavourable principal stress orientations. The existence of such cages is demonstrated here by independent analytical and numerical methods. We explain

  16. Cementing a wellbore using cementing material encapsulated in a shell

    Energy Technology Data Exchange (ETDEWEB)

    Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Floyd, III, William C.; Spadaccini, Christopher M.; Vericella, John J.; Cowan, Kenneth Michael

    2017-03-14

    A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

  17. Cementing a wellbore using cementing material encapsulated in a shell

    Science.gov (United States)

    Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Spadaccini, Christopher M.; Cowan, Kenneth Michael

    2016-08-16

    A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

  18. Cementing a wellbore using cementing material encapsulated in a shell

    Energy Technology Data Exchange (ETDEWEB)

    Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Spadaccini, Christopher M.; Cowan, Kenneth Michael

    2016-08-16

    A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

  19. Effective Permeability Change in Wellbore Cement with Carbon Dioxide Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Um, Wooyong; Jung, Hun Bok; Martin, Paul F.; McGrail, B. Peter

    2011-11-01

    Portland cement, a common sealing material for wellbores for geological carbon sequestration was reacted with CO{sub 2} in supercritical, gaseous, and aqueous phases at various pressure and temperature conditions to simulate cement-CO{sub 2} reaction along the wellbore from carbon injection depth to the near-surface. Hydrated Portland cement columns (14 mm diameter x 90 mm length; water-to-cement ratio = 0.33) including additives such as steel coupons and Wallula basalt fragments were reacted with CO{sub 2} in the wet supercritical (the top half) and dissolved (the bottom half) phases under carbon sequestration condition with high pressure (10 MPa) and temperature (50 C) for 5 months, while small-sized hydrated Portland cement columns (7 mm diameter x 20 mm length; water-to-cement ratio = 0.38) were reacted with CO{sub 2} in dissolved phase at high pressure (10 MPa) and temperature (50 C) for 1 month or with wet CO{sub 2} in gaseous phase at low pressure (0.2 MPa) and temperature (20 C) for 3 months. XMT images reveal that the cement reacted with CO{sub 2} saturated groundwater had degradation depth of {approx}1 mm for 1 month and {approx}3.5 mm for 5 month, whereas the degradation was minor with cement exposure to supercritical CO{sub 2}. SEM-EDS analysis showed that the carbonated cement was comprised of three distinct zones; the innermost less degraded zone with Ca atom % > C atom %, the inner degraded zone with Ca atom % {approx} C atom % due to precipitation of calcite, the outer degraded zone with C atom % > Ca atom % due to dissolution of calcite and C-S-H, as well as adsorption of carbon to cement matrix. The outer degraded zone of carbonated cement was porous and fractured because of dissolution-dominated reaction by carbonic acid exposure, which resulted in the increase in BJH pore volume and BET surface area. In contrast, cement-wet CO{sub 2}(g) reaction at low P (0.2 MPa)-T (20 C) conditions for 1 to 3 months was dominated by precipitation of micron

  20. A multi-feedzone geothermal wellbore simulator

    Energy Technology Data Exchange (ETDEWEB)

    Bjornsson, G.

    1987-05-01

    The main objective of this work is to develop a multiple feedzone wellbore model for single- or two-phase flow in vertical wells. It has been demonstrated in various fields (e.g., oil and gas and geothermal) that multiple feedzones with different pressure potentials can significantly effect the well performance in the long run. Very little work in this subject has been done to date, but the importance of the subject is becoming more and more evident. 55 refs., 33 figs., 4 tabs.

  1. Closure of open wellbores in creeping salt sheets

    NARCIS (Netherlands)

    Weijermars, R.; Jackson, M.P.A.; Van Harmelen, A.

    2013-01-01

    Safe exploration and production of pre-salt (or subsalt) hydrocarbons require that drilling operations be optimized. We introduce analytical models of wellbore closure, accounting for variations in both the wellbore net pressure and far-field flow rate of an autochthonous or allochthonous salt sheet

  2. Investigation of wellbore cooling by circulation and fluid penetration into the formation using a wellbore thermal simulator computer code

    Energy Technology Data Exchange (ETDEWEB)

    Duda, L.E.

    1985-01-01

    The high temperatures of geothermal wells present severe problems for drilling, logging, and developing these reservoirs. Cooling the wellbore is perhaps the most common method to solve these problems. However, it is usually not clear what may be the most effective wellbore cooling mechanism for a given well. In this paper, wellbore cooling by the use of circulation or by fluid injection into the surrounding rock is investigated using a wellbore thermal simulator computer code. Short circulation times offer no prolonged cooling of fluid in the wellbore, but long circulation times (greater than ten or twenty days) greatly reduce the warming rate after shut-in. The dependence of the warming rate on the penetration distance of cooler temperatures into the rock formation (as by fluid injection) is investigated. Penetration distances of greater than 0.6 m appear to offer a substantial reduction in the warming rate. Several plots are shown which demonstrate these effects. 16 refs., 6 figs.

  3. Wellbore stability in shales considering chemo-poroelastic effects

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Ewerton M.P.; Pastor, Jorge A.S.C.; Fontoura, Sergio A.B.; Rabe, Claudio [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. de Engenharia Civil. Grupo de Tecnologia e Engenharia de Petroleo

    2004-07-01

    Under compaction and low geothermal gradients are deep water characteristics. Both under compaction and low geothermal gradients generate considerable thickness of smectite-rich shales. These rocks are the major source of wellbore stability problems, because they are susceptible to adverse physico-chemical reactions when in contact with inadequate drilling fluids. Due shales are low permeability rocks diffusion processes dominate the changes of pore pressure around wellbore. Diffusion of fluids, ions and temperature occurs in shales during drilling and demand a fully coupled modelling taking account these factors. Despite temperature importance, in this paper wellbore stability in shales is analyzed through a model that considers only the coupling between poroelastic and physico-chemical effects. The coupled equations are solved analytically and have been implemented in a computational simulator with user-friendly interface. Time-dependent simulations of wellbore stability in shales are presented for a typical deep water scenario. The results show that physico-chemical effects change pore pressure around wellbore and have high impact on the wellbore stability. (author)

  4. Probabilistic Approach in Wellbore Stability Analysis during Drilling

    Directory of Open Access Journals (Sweden)

    Mahmood R. Al-Khayari

    2016-01-01

    Full Text Available In oil industry, wellbore instability is the most costly problem that a well drilling operation may encounter. One reason for wellbore failure can be related to ignoring rock mechanics effects. A solution to overcome this problem is to adopt in situ stresses in conjunction with a failure criterion to end up with a deterministic model that calculates collapse pressure. However, the uncertainty in input parameters can make this model misleading and useless. In this paper, a new probabilistic wellbore stability model is presented to predict the critical drilling fluid pressure before the onset of a wellbore collapse. The model runs Monte Carlo simulation to capture the effects of uncertainty in in situ stresses, drilling trajectories, and rock properties. The developed model was applied to different in situ stress regimes: normal faulting, strike slip, and reverse faulting. Sensitivity analysis was applied to all carried out simulations and found that well trajectories have the biggest impact factor in wellbore instability followed by rock properties. The developed model improves risk management of wellbore stability. It helps petroleum engineers and field planners to make right decisions during drilling and fields’ development.

  5. Mono Lake Excursion Reviewed

    Science.gov (United States)

    Liddicoat, J. C.; Coe, R. S.

    2007-05-01

    The Mono Lake Excursion as recorded in the Mono Basin, CA, has an older part that is about negative 30 degrees inclination and about 300 degrees declination during low relative field intensity. Those paleomagnetic directions are closely followed by greater than 80 degrees positive inclination and east declination of about 100 degrees during higher relative field intensity. A path of the Virtual Geomagnetic Poles (VGPs) for the older part followed from old to young forms a large clockwise loop that reaches 35 degrees N latitude and is centered at about 35 degrees E longitude. That loop is followed by a smaller one that is counterclockwise and centered at about 70 degrees N latitude and 270 degrees E longitude (Denham & Cox, 1971; Denham, 1974; Liddicoat & Coe, 1979). The Mono Lake Excursion outside the Mono Basin in western North America is recorded as nearly the full excursion at Summer Lake, OR (Negrini et al., 1984), and as the younger portion of steep positive inclination/east declination in the Lahontan Basin, NV. The overall relative field intensity during the Mono Lake Excursion in the Lahontan Basin mirrors very closely the relative field intensity in the Mono Basin (Liddicoat, 1992, 1996; Coe & Liddicoat, 1994). Using 14C and 40Ar/39Ar dates (Kent et al., 2002) and paleoclimate and relative paleointensity records (Zimmerman et al., 2006) for the Mono Lake Excursion in the Mono Basin, it has been proposed that the Mono Lake Excursion might be older than originally believed and instead be the Laschamp Excursion at about 40,000 yrs B.P. (Guillou et al., 2004). On the contrary, we favor a younger age for the Mono Lake Excursion, about 32,000 yrs B.P., using the relative paleointensity in the Mono Basin and Lahontan Basin and 14C dates from the Lahontan Basin (Benson et al., 2002). The age of about 32,000 yrs B.P. is also in accord with the age (32,000- 34,000 yrs B.P.) reported by Channell (2006) for the Mono Lake Excursion at ODP Site 919 in the Irminger Basin

  6. Application of Cement Science to Improved Wellbore Infrastructures Mileva Radonjic and Darko Kupresan Craft & Hawkins Department of Petroleum Engineering, Louisiana State University, USA Corresponding author: mileva@lsu.edu Key words: micro-annular gas flow, nano-properties of wellbore cements, micro-porosity

    Science.gov (United States)

    Radonjic, M.

    2015-12-01

    Recent focus on carbon emission from cement industry inspired researchers to improve CSH properties by reducing Ca/Si ratio at the nanoscale, and lower porosity (permeability) of hydrated cement at micro scale. If implemented in wellbore cement technology, both of these efforts could provide advanced properties for wellbore infrastructure. These advancements would further reduce the issue of leaky wellbores in fluid injections, hydraulic fracturing and subsurface storage for existing operating wells. Numerous inadequately abandoned wells, however, pose more complex engineering problems, primarily due to the difficulty in locating fluid flow pathways along the wellbore structure. In order to appreciate the difficulty of this problem, we need to remind ourselves that: a typical 30,000-ft. wellbore with an average production casing of 8 inches in diameter can be presented in scale by a 6-m long human hair of 150 μm these structures are placed in the subsurface, often not just vertical in geometry but deviated close to 90° tangent where monitoring and remediation becomes demanding and if we consider that wellbore cement is not continuously placed along the wellbore and it is approximately 1/10 of a wellbore diameter, we can see that the properties of these materials demand application of nano-science and a different scale phenomena than perhaps previously acknowledged. The key concept behind Ca/Si reduction associated with improved mechanical properties is traditionally achieved chemically, by addition of supplemental cementitious materials. In our study we have tried to evaluate CSH alterations due to mechanically induced phase transformation. The data suggest that confined compression-extrusion of hydrated wellbore cement and the consequent propagation of pore water can change cement composition by dissolving and removing Ca, therefore reducing Ca/Si of cement phases. The advantage of this approach is that the process is less impacted by pressure

  7. Advanced wellbore thermal simulator GEOTEMP2. Appendix. Computer program listing

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, R.F.

    1982-02-01

    This appendix gives the program listing of GEOTEMP2 with comments and discussion to make the program organization more understandable. This appendix is divided into an introduction and four main blocks of code: main program, program initiation, wellbore flow, and wellbore heat transfer. The purpose and use of each subprogram is discussed and the program listing is given. Flowcharts will be included to clarify code organization when needed. GEOTEMP2 was written in FORTRAN IV. Efforts have been made to keep the programing as conventional as possible so that GEOTEMP2 will run without modification on most computers.

  8. The Framework Dedicated to Three Phase Flows Wellbore Modelling

    Directory of Open Access Journals (Sweden)

    Bartlomiej Bielecki

    2015-01-01

    Full Text Available To predict physical properties in a wellbore during oil and gas production, scientists use empirical correlations or mechanistic approach algorithms. The typical research in this field is concentrated on a single property analysis as heat transfer, pressure, temperature, and so forth. Here the most proper correlations, regarding the subject, are presented. And the authors studied how to join all correlations into the full framework which returns all production parameters at every depth in a wellbore. Additionally, the presented simulation results are studied here. Based on presented algorithms, the proper tool has been applied and the results shown in this paper are taken from this application.

  9. Scour properties of mono bucket foundation

    DEFF Research Database (Denmark)

    Stroescu, Ionut Emanuel; Frigaard, Peter Bak

    2016-01-01

    Field experience proved that the Mono Bucket Foundations (MBFs) have good response against scour development. Moreover, the ratio between large diameter (bucket lid) and the small diameter (shaft tower) is the driving parameter for the process of erosion/backfill, like scour protection diameter...... in the case of scour protected monopiles. However, the structural design to reduce the scour development for MBFs is still open to optimization. The influences of parameters that generate backfill and scour, the transfer load webs and the misalignment with seabed, have not been systematically studied until...

  10. Wellbore stability analysis in chemically active shale formations

    Directory of Open Access Journals (Sweden)

    Shi Xiang-Chao

    2016-01-01

    Full Text Available Maintaining wellbore stability involves significant challenges when drilling in low-permeability reactive shale formations. In the present study, a non-linear thermo-chemo-poroelastic model is provided to investigate the effect of chemical, thermal, and hydraulic gradients on pore pressure and stress distributions near the wellbores. The analysis indicates that when the solute concentration of the drilling mud is higher than that of the formation fluid, the pore pressure and the effective radial and tangential stresses decrease, and v. v. Cooling of the lower salinity formation decreases the pore pressure, radial and tangential stresses. Hole enlargement is the combined effect of shear and tensile failure when drilling in high-temperature shale formations. The shear and tensile damage indexes reveal that hole enlargement occurs in the vicinity of the wellbore at an early stage of drilling. This study also demonstrates that shale wellbore stability exhibits a time-delay effect due to changes in the pore pressure and stress. The delay time computed with consideration of the strength degradation is far less than that without strength degradation.

  11. Optimization of SAGD wellbore completions : short production tubing string sensitivities

    Energy Technology Data Exchange (ETDEWEB)

    Cokar, M.; Graham, J. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Petro-Canada, Calgary, AB (Canada)

    2008-10-15

    This study investigated the effects of changing the landing position of short production tubing strings near the heel of steam assisted gravity drainage (SAGD) production wells. A homogenous discretized wellbore model was used to model the reservoir and wellbore simultaneously in order to study wellbore and reservoir interactions. The aim of the study was to develop a method of optimizing bitumen production and determining the most economical position for wellbore strings. Simulations were conducted to examine the effect of shortening the production tubing string and examine the impact of extending the tubing string beyond the heel of the well on bitumen bitumen production rates and the steam oil ratio (SOR). Results of the study showed that a shortened string decreased bitumen production rates, while the amounts of steam produced through the tubing string increased. When the tubing string was extended past the heel of the well, bitumen production rates remained the same, but steam injection rates and SOR decreased. A lower pressure differential between the injector and producer wells was also observed. The study showed that SAGD producers can re-position production tubing strings in order to determine ratios of liquid production. It was concluded that although placing the short production tubing string close to the heel increased oil production, a longer tubing string improved production rates while lowering operating costs. 3 refs., 3 tabs., 35 figs.

  12. Well-control methods and practices in small-diameter wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Bode, D.J.; Noffke, R.B.; Nickens, H.V. (Amoco Production Co. (US))

    1991-11-01

    This paper reports on slim-hole drilling and continuous coring for oil and gas exploration which has been impeded by lack of documentation of well-control methods for small-annulus drilling. Research in annular pressure losses, kick identification, wireline swab effects, and dynamic-kill well-control effectiveness helped develop a slim-hole well-control methodology.

  13. Wellbore integrity analysis of a natural CO2 producer

    KAUST Repository

    Crow, Walter

    2010-03-01

    Long-term integrity of existing wells in a CO2-rich environment is essential for ensuring that geological sequestration of CO2 will be an effective technology for mitigating greenhouse gas-induced climate change. The potential for wellbore leakage depends in part on the quality of the original construction as well as geochemical and geomechanical stresses that occur over its life-cycle. Field data are essential for assessing the integrated effect of these factors and their impact on wellbore integrity, defined as the maintenance of isolation between subsurface intervals. In this report, we investigate a 30-year-old well from a natural CO2 production reservoir using a suite of downhole and laboratory tests to characterize isolation performance. These tests included mineralogical and hydrological characterization of 10 core samples of casing/cement/formation, wireline surveys to evaluate well conditions, fluid samples and an in situ permeability test. We find evidence for CO2 migration in the occurrence of carbonated cement and calculate that the effective permeability of an 11′-region of the wellbore barrier system was between 0.5 and 1 milliDarcy. Despite these observations, we find that the amount of fluid migration along the wellbore was probably small because of several factors: the amount of carbonation decreased with distance from the reservoir, cement permeability was low (0.3-30 microDarcy), the cement-casing and cement-formation interfaces were tight, the casing was not corroded, fluid samples lacked CO2, and the pressure gradient between reservoir and caprock was maintained. We conclude that the barrier system has ultimately performed well over the last 3 decades. These results will be used as part of a broader effort to develop a long-term predictive simulation tool to assess wellbore integrity performance in CO2 storage sites. © 2009 Elsevier Ltd. All rights reserved.

  14. Advanced wellbore thermal simulator GEOTEMP2 user manual

    Energy Technology Data Exchange (ETDEWEB)

    Mondy, L.A.; Duda, L.E.

    1984-11-01

    GEOTEMP2 is a wellbore thermal simulator computer code designed for geothermal drilling and production applications. The code treats natural and forced convection and conduction within the wellbore and heat conduction within the surrounding rock matrix. A variety of well operations can be modeled including injection, production, forward, and reverse circulation with gas or liquid, gas or liquid drilling, and two-phase steam injection and production. Well completion with several different casing sizes and cement intervals can be modeled. The code allows variables suchas flow rate to change with time enabling a realistic treatment of well operations. This user manual describes the input required to properly operate the code. Ten sample problems are included which illustrate all the code options. Complete listings of the code and the output of each sample problem are provided.

  15. Prediction of Dynamic Wellbore Pressure in Gasified Fluid Drilling

    Institute of Scientific and Technical Information of China (English)

    Wang Zhiming; Ping Liqiu; Zou Ke

    2007-01-01

    The basis of designing gasified drilling is to understand the behavior of gas/liquid two-phase flow in the wellbore. The equations of mass and momentum conservation and equation of fluid flow in porous media were used to establish a dynamic model to predict weIlbore pressure according to the study results of Ansari and Beggs-Brill on gas-liquid two-phase flow. The dynamic model was solved by the finite difference approach combined with the mechanistic steady state model. The mechanistic dynamic model was numerically implemented into a FORTRAN 90 computer program and could simulate the coupled flow of fluid in wellbore and reservoir. The dynamic model revealed the effects of wellhead back pressure and injection rate of gas/liquid on bottomhole pressure. The model was validated against full-scale experimental data, and its 5.0% of average relative error could satisfy the accuracy requirements in engineering design.

  16. Analysis of pressure buildup data influenced by wellbore phase redistribution

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, L.G.; Jones, J.R.; Reynolds, A.C.

    1986-10-01

    This work considers the influence of wellbore phase redistribution effects on the analysis of pressure buildup data. First, the authors show that the pressure responses observed when phase redistribution effects exist consist of three distinct types and delineate the conditions under which each type exists. Second, they investigate the reliability of Fair's type curves for analyzing pressure data. Third, for each type of pressure response, they provide rules for determining when the conventional semilog straight line will begin on a semilog plot of pressure data vs. time. They also consider general procedures that are based on Duhamel's principle for analyzing pressure data when sandface flow rates are also available. They discuss the application of these methods to analyze pressure data influenced by wellbore storage effects and investigate the effect that errors in the measured sandface rate have on the analysis.

  17. Wellbore Surveying While Drilling Based on Kalman Filtering

    Directory of Open Access Journals (Sweden)

    Mahmoud ElGizawy

    2010-01-01

    Full Text Available Problem statement: Oil and gas are global fuels obtained primarily from drilling wells in underground terrestrial reservoirs. Vertical drilling is preferred because of its simplicity and therefore low cost, but subsurface targets can often be procured only by directing the wellbore along predefined non-vertical trajectories. For instance, directional drilling must be employed to reach locations inaccessible to the drilling rig, to side track an existing well (multilateral drilling, or to drill multiple wells from the same offshore platform (horizontal drilling. Approach: A complete knowledge of the wellbore direction and orientation during the drilling process is essential to guarantee proper directional drilling procedure. Results: Thus, besides the conventional drilling assembly, directional drilling operations require sensors to provide azimuth, inclination and toolface angles of the drill. These sensors are part of the Measurement-While-Drilling (MWD tool, which in current technology is installed several feet behind the drill bit. In such systems, values for inclination and toolface angles are determined from accelerometer measurements at predetermined stationary surveying stations; these values are then incorporated with magnetometer measurements to deliver the azimuth angle. Values for inclination and azimuth angles at the current surveying station are combined with those from the previous station to compute the position of the probe. However, there is no accurate information about the wellbore trajectory between survey stations. Additionally, the magnetic field of the magnetometers has deleterious effect on the overall accuracy of surveying measurements. Conclusion: A method to provide continuous information about the wellbore trajectory has been developed in this study. The module developed integrates a Rotary Steerable System (RSS and MWD tool into one drilling probe utilizing Inertial Navigation System (INS technology. This is achieved

  18. Effect of wellbore storage on the analysis of multiphase-flow-pressure data

    Energy Technology Data Exchange (ETDEWEB)

    Hatzignatiou, D.G. (Univ. of Alaska, Fairbanks, AK (United States)); Peres, A.M.M. (Petrobras S.A., Rio de Janeiro (Brazil)); Reynolds, A.C. (Univ. of Tulsa, OK (United States))

    1994-09-01

    This paper investigates the effect of wellbore storage on the analysis of pressure drawdown data obtained at a well producing a solution-gas-drive reservoir. Wellbore storage effects are incorporated by specifying a sandface oil flow rate that increases exponentially from zero to the specified constant value of the oil flow rate at the surface. Use of new computational equations derived here shows that effective oil permeability as a pointwise function of pressure can be computed directly from the measured values of the flowing wellbore pressure, provided the sandface oil flow rate is measured and incorporated into the analysis. If the sandface flow rate is unknown, effective permeability can be computed only after wellbore storage effects become negligible. In all cases, a semilog plot of wellbore pressure squared vs. time is shown to be a viable method for estimating effective oil permeability at initial conditions, effective oil permeability at the final flowing wellbore pressure value, and mechanical skin factor.

  19. Hydraulic fracturing model featuring initiation beyond the wellbore wall for directional well in coal bed

    Science.gov (United States)

    Li, Yuwei; Jia, Dan; Wang, Meng; Liu, Jia; Fu, Chunkai; Yang, Xinliang; Ai, Chi

    2016-08-01

    In developing internal fracture systems in coal beds, the initiation mechanism differs greatly from that of conventional ones and initiations may be produced beyond the wellbore wall. This paper describes the features of the internal structure of coal beds and RFPA2D simulation is used to attest the possible occurrence of initiation beyond the wellbore wall in coal bed hydraulic fracturing. Using the theory of elasticity and fracture mechanics, we analyse the stress distribution in the vicinal coal rock. Then by taking into consideration the effects of the spatial relationship between coal bed cleats and the wellbore, we establish a model for calculating both tensile and shear initiation pressure that occur along cleats beyond the wellbore wall. The simulation in this paper indicates that for shear initiations that happen along coal cleats, the pressure required to initiate fracture for cleats beyond the wellbore wall is evidently lower than that on the wellbore wall, thus it is easier to initiate shear fractures for cleats beyond the wellbore wall. For tensile failure, the pressure required to initiate tensile fracture for cleats beyond the wellbore wall is obviously higher than that for cleats at the wellbore wall, thus it is easier to initiate tensile fractures for cleats at the wellbore wall. On the one hand, this paper has proved the possible occurrence of initiations beyond the wellbore wall and has changed the current assumption that hydraulic fractures can only occur at the wellbore wall. On the other hand, the established theoretical model provides a new approach to calculating the initiation pressure in hydraulic fracturing.

  20. Study on temperature distribution along wellbore of fracturing horizontal wells in oil reservoir

    Directory of Open Access Journals (Sweden)

    Junjun Cai

    2015-12-01

    Full Text Available The application of distributed temperature sensors (DTS to monitor producing zones of horizontal well through a real-time measurement of a temperature profile is becoming increasingly popular. Those parameters, such as flow rate along wellbore, well completion method, skin factor, are potentially related to the information from DTS. Based on mass-, momentum-, and energy-balance equations, this paper established a coupled model to study on temperature distribution along wellbore of fracturing horizontal wells by considering skin factor in order to predict wellbore temperature distribution and analyze the factors influencing the wellbore temperature profile. The models presented in this paper account for heat convective, fluid expansion, heat conduction, and viscous dissipative heating. Arriving temperature and wellbore temperature curves are plotted by computer iterative calculation. The non-perforated and perforated sections show different temperature distribution along wellbore. Through the study on the sensitivity analysis of skin factor and flow rate, we come to the conclusion that the higher skin factor generates larger temperature increase near the wellbore, besides, temperature along wellbore is related to both skin factors and flow rate. Temperature response type curves show that the larger skin factor we set, the less temperature augmenter from toe to heel could be. In addition, larger flow rate may generate higher wellbore temperature.

  1. Non-Darcian Flow Toward a Finite-Diameter Vertical Well in a Confined Aquifer

    Institute of Scientific and Technical Information of China (English)

    WEN Zhang; HUANG Guan-Hua; ZHAN Hong-Bin

    2008-01-01

    Non-Darcian radial flow toward a finite-diameter,fully penetrating well in a confined aquifer was analyzed on the basis of the Izbash equation with consideration of the wellbore storage effect.We derived semi-analytical solutions of drawdown by using the Boltzmann transform,and obtained approximate analytical solutions of the drawdown at early and late times.MATLAB programs were developed to facilitate computation of the semi-analytical solutions.The turbulence factor v which was directly related to the pumping rate appeared to have negligible influence upon the wellbore well function at early times,but imposed significant influence at intermediate and late times.However,the turbulence factor v imposed non-negligible influence upon the aquifer well function during the entire pumping period,provided that the observation point was not sufficiently close to the wellbore.Sensitivity analysis indicated that the power index n in the Izbash equation had less influence on the type curves at the face of the pumping wellbore,but had much greater influence upon the well function in the aquifer.As the n values increased,the drawdown in the aquifer decreased at early times and increased at late times.The Boltzmann transformation could only be used in an approximate sense for radial non-Darcian flow problems.This approximation would provide accurate solutions at early times,and introduce small but consistent discrepancies at intermediate and late times for the wellbore well function.

  2. Crystal growth of 50 cm square mono-like Si by directional solidification and its characterization

    Science.gov (United States)

    Miyamura, Y.; Harada, H.; Jiptner, K.; Chen, J.; Prakash, R. R.; Nakano, S.; Gao, B.; Kakimoto, K.; Sekiguchi, T.

    2014-09-01

    Seed-assisted growth of mono crystalline-like Silicon (mono-like Si) ingots of 50 cm square has been performed. By controlling the shape of the liquid-solid interface, a mono-like crystal was grown from a small seed of 20 cm diameter. Several developments to reduce the carbon incorporation have been realized as can be seen from the shiny ingot surfaces. The dislocation density is reduced to the order of 104 cm-2.

  3. Wellbore inertial navigation system (WINS) software development and test results

    Energy Technology Data Exchange (ETDEWEB)

    Wardlaw, R. Jr.

    1982-09-01

    The structure and operation of the real-time software developed for the Wellbore Inertial Navigation System (WINS) application are described. The procedure and results of a field test held in a 7000-ft well in the Nevada Test Site are discussed. Calibration and instrumentation error compensation are outlined, as are design improvement areas requiring further test and development. Notes on Kalman filtering and complete program listings of the real-time software are included in the Appendices. Reference is made to a companion document which describes the downhole instrumentation package.

  4. Geomechanical analyses to investigate wellbore/mine interactions in the Potash Enclave of Southeastern New Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L.; Bean, James E. (Sandia Staffing Alliance, LLC, Albuquerque, NM); Arguello, Jose Guadalupe, Jr.; Stone, Charles Michael

    2010-04-01

    Geomechanical analyses have been performed to investigate potential mine interactions with wellbores that could occur in the Potash Enclave of Southeastern New Mexico. Two basic models were used in the study; (1) a global model that simulates the mechanics associated with mining and subsidence and (2) a wellbore model that examines the resulting interaction impacts on the wellbore casing. The first model is a 2D approximation of a potash mine using a plane strain idealization for mine depths of 304.8 m (1000 ft) and 609.6 m (2000 ft). A 3D wellbore model then considers the impact of bedding plane slippage across single and double cased wells cemented through the Salado formation. The wellbore model establishes allowable slippage to prevent casing yield.

  5. Characteristics of mechanical wellbore failure and damage: Insights of discrete element modelling and application to CO2 storage

    NARCIS (Netherlands)

    Heege, J.H. ter; Orlic, B.; Hoedeman, G.C.

    2015-01-01

    Wellbore zonal isolation is particularly important for subsurface storage of CO2, where well integrity must be ensured for very long time spans. In this study, three dimensional discrete element models of wellbore systems have been used to simulate failure and damage of wellbore cement and surroundi

  6. Development of an Ultrasonic Phased Array System for Wellbore Integrity Evaluation and Near-Wellbore Fracture Network Mapping of Injection and Production Wells in Geothermal Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Almansouri, Hani [Purdue University; Foster, Benjamin [Purdue University; Kisner, Roger A [ORNL; Polsky, Yarom [ORNL; Bouman, Charlie [Purdue University

    2016-01-01

    This paper documents our progress developing an ultrasound phased array system in combination with a model-based iterative reconstruction (MBIR) algorithm to inspect the health of and characterize the composition of the near-wellbore region for geothermal reservoirs. The main goal for this system is to provide a near-wellbore in-situ characterization capability that will significantly improve wellbore integrity evaluation and near well-bore fracture network mapping. A more detailed image of the fracture network near the wellbore in particular will enable the selection of optimal locations for stimulation along the wellbore, provide critical data that can be used to improve stimulation design, and provide a means for measuring evolution of the fracture network to support long term management of reservoir operations. Development of such a measurement capability supports current hydrothermal operations as well as the successful demonstration of Engineered Geothermal Systems (EGS). The paper will include the design of the phased array system, the performance specifications, and characterization methodology. In addition, we will describe the MBIR forward model derived for the phased array system and the propagation of compressional waves through a pseudo-homogenous medium.

  7. Stress State Analysis in Aspect of Wellbore Drilling Direction

    Science.gov (United States)

    Knez, Dariusz

    2014-03-01

    Drilling directional wells challenges designers. Apart from known problems until now they face exact description of stress distribution in near wellbore region issue. Paper presents analysis of stress state taking into account drilling direction. The transposed in-situ stress state relative to the borehole coordinate system (Cartesian borehole coordinate system) and the total stress component at the borehole wall (cylindrical coordinate system) exhibits cyclic behaviour with respect to drilling direction of borehole. It allows to find optimal wellbore path Wiercenie otworów kierunkowych stanowi duże wyzwanie dla projektantów. Poza problemami typowymi obecnie staja oni w obliczu zagadnienia dokładnego opisu rozkładu naprężeń w strefie przyotworowej. Artykuł przedstawia analizę stanu naprężeń w aspekcie kierunku wiercenia. Rozkład naprężeń transponowany do układu odniesienia związanego z otworem wiertniczym (kartezjański układ współrzędnych zgodny z kierunkiem otworu wiertniczego) oraz składowe naprężenia na ścianie otworu wiertniczego (w cylindrycznym układzie odniesienia) wykazują cykliczną zmienność zależną od kierunku wiercenia. Pozwala to na określenie optymalnej trajektorii osi otworu wiertniczego

  8. How Long Is Mono Contagious?

    Science.gov (United States)

    ... it is contagious. Once someone gets mono, the virus stays in that person's body for life. That doesn't mean that you are always ... as long as 18 months. After that, the virus remains dormant (inactive) in the body for the rest of a person's life. If you've had mono, the virus can ...

  9. A Graph Theoretic Approach for Hydraulic Fracturing and Wellbore Leakage Risk Modeling

    Science.gov (United States)

    Glosser, D.; Rose, K.; Bauer, J. R.; Warner, T.

    2016-12-01

    Recent large scale development of unconventional formations for fossil energy has raised concerns over the potential for fluid leakage between subsurface systems and wellbores. This is particularly true in regions with extensive drilling history, where spatial densities of wellbores are higher, and where significant uncertainties in the location and mechanical integrity of such wellbores exist. The generation of induced fracture networks during hydraulic fracturing may increase subsurface connectivity, and create the potential for unwanted fluid migration between operational and legacy wellbores and subsurface fracture networks. We present a graph theoretic approach for identifying geospatial regions and wellbores at increased risk for subsurface connectivity based on wellbore proximity and local geologic characteristics. The algorithm transforms user inputted geospatial data (geologic and wellbore x,y,z) to graph structure, where wellbores are represented as nodes, and where potential overlapping fracture network zones are represented as edges. The algorithm can be used to complement existing fracture models to better account for the reach of induced fractures, and to identify spatial extents at increased risk for unwanted subsurface connectivity. Additionally, the model can be used to identify regions in need of geophysical detection methods for locating undocumented wells. As a result, the method can be part of a cumulative strategy to reduce uncertainty inherent to combined geologic and engineered systems. The algorithm has been successfully tested against a known leakage scenario in Pennsylvania. In addition to identifying wells associated with the leakage event, the algorithm identified two other higher risk networks in the region. The algorithm output provides valuable information for industry to develop environmentally safe drilling and injection plans; and for regulators to identify specific wellbores at greater risk for leakage, and to develop targeted

  10. AnalyzeHOLE - An Integrated Wellbore Flow Analysis Tool

    Science.gov (United States)

    Halford, Keith

    2009-01-01

    Conventional interpretation of flow logs assumes that hydraulic conductivity is directly proportional to flow change with depth. However, well construction can significantly alter the expected relation between changes in fluid velocity and hydraulic conductivity. Strong hydraulic conductivity contrasts between lithologic intervals can be masked in continuously screened wells. Alternating intervals of screen and blank casing also can greatly complicate the relation between flow and hydraulic properties. More permeable units are not necessarily associated with rapid fluid-velocity increases. Thin, highly permeable units can be misinterpreted as thick and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because vertical flow fields are induced near the wellbore. AnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, provides a better alternative for simulating and evaluating complex well-aquifer system interaction. A pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well, pumping tests. Water-quality changes in the pumping well are simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1) creating model input files, (2) executing MODFLOW, MODPATH, PEST, and supporting FORTRAN routines, and (3) importing and graphically

  11. AnalyzeHOLE: An Integrated Wellbore Flow Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    Keith J. Halford

    2009-10-01

    Conventional interpretation of flow logs assumes that hydraulic conductivity is directly proportional to flow change with depth. However, well construction can significantly alter the expected relation between changes in fluid velocity and hydraulic conductivity. Strong hydraulic conductivity contrasts between lithologic intervals can be masked in continuously screened wells. Alternating intervals of screen and blank casing also can greatly complicate the relation between flow and hydraulic properties. More permeable units are not necessarily associated with rapid fluid-velocity increases. Thin, highly permeable units can be misinterpreted as thick and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because vertical flow fields are induced near the wellbore. AnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, provides a better alternative for simulating and evaluating complex well-aquifer system interaction. A pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well, pumping tests. Water-quality changes in the pumping well are simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1) creating model input files, (2) executing MODFLOW, MODPATH, PEST, and supporting FORTRAN routines, and (3) importing and graphically

  12. Numerical Simulation on Open Wellbore Shrinkage and Casing Equivalent Stress in Bedded Salt Rock Stratum

    Directory of Open Access Journals (Sweden)

    Jianjun Liu

    2013-01-01

    Full Text Available Most salt rock has interbed of mudstone in China. Owing to the enormous difference of mechanical properties between the mudstone interbed and salt rock, the stress-strain and creep behaviors of salt rock are significantly influenced by neighboring mudstone interbed. In order to identify the rules of wellbore shrinkage and casings equivalent stress in bedded salt rock stratum, three-dimensional finite difference models were established. The effects of thickness and elasticity modulus of mudstone interbed on the open wellbore shrinkage and equivalent stress of casing after cementing operation were studied, respectively. The results indicate that the shrinkage of open wellbore and equivalent stress of casings decreases with the increase of mudstone interbed thickness. The increasing of elasticity modulus will reduce the shrinkage of open wellbore and casing equivalent stress. Research results can provide the scientific basis for the design of mud density and casing strength.

  13. Numerical simulation on open wellbore shrinkage and casing equivalent stress in bedded salt rock stratum.

    Science.gov (United States)

    Liu, Jianjun; Zhang, Linzhi; Zhao, Jinzhou

    2013-01-01

    Most salt rock has interbed of mudstone in China. Owing to the enormous difference of mechanical properties between the mudstone interbed and salt rock, the stress-strain and creep behaviors of salt rock are significantly influenced by neighboring mudstone interbed. In order to identify the rules of wellbore shrinkage and casings equivalent stress in bedded salt rock stratum, three-dimensional finite difference models were established. The effects of thickness and elasticity modulus of mudstone interbed on the open wellbore shrinkage and equivalent stress of casing after cementing operation were studied, respectively. The results indicate that the shrinkage of open wellbore and equivalent stress of casings decreases with the increase of mudstone interbed thickness. The increasing of elasticity modulus will reduce the shrinkage of open wellbore and casing equivalent stress. Research results can provide the scientific basis for the design of mud density and casing strength.

  14. Numerical assessment of the mechanical stability in vertical, directional and horizontal wellbores

    Institute of Scientific and Technical Information of China (English)

    Kamran Goshtasbi; Ayub Elyasi; Ali Naeimipour

    2013-01-01

    In this research the stability of wellbore is evaluated in seven different stress regimes and diverse orien-tations using FLAC3D software. The normalized yielded zone area (NYZA, i.e., the ratio of surrounding yielded cross-sectional area to initial area of wellbore) is determined for different mud pressures as well as diverse orientations of wellbore. By means of MATLAB software the best curve is fitted to the recorded points and then the optimized mud pressure is calculated using these plots. The optimized orientation is selected considering these data. Finally the mud pressure resulted from this method was compared with the mud pressure obtained from the Mogi-Coulomb criterion and then with the fields data. The minimum allowable mud pressure obtained from the NYZA criterion is close to actual data and the value obtained from the Mogi-Coulomb criterion. Hence, the NYZA is considered to be an appropriate criterion for well-bore stability analysis.

  15. A review of the shale wellbore stability mechanism based on mechanical–chemical coupling theories

    Directory of Open Access Journals (Sweden)

    Qiangui Zhang

    2015-06-01

    Full Text Available Wellbore instability in hard brittle shale is a critical topic related to the effective exploitation of shale gas resources. This review first introduces the physical–chemical coupling theories applied in shale wellbore stability research, including total water absorption method, equivalent pore pressure method, elasticity incremental method of total water potential and non-equilibrium thermodynamic method. Second, the influences of water activity, membrane efficiency, clay content and drilling fluid on shale wellbore instability are summarized. Results demonstrate that shale and drilling fluid interactions can be the critical factors affecting shale wellbore stability. The effects of thermodynamics and electrochemistry may also be considered in the future, especially the microscopic reaction of shale and drilling fluid interactions. An example of this reaction is the chemical reaction between shale components and drilling fluid.

  16. Pulse testing in the presence of wellbore storage and skin effects

    Energy Technology Data Exchange (ETDEWEB)

    Ogbe, D.O.; Brigham, W.E.

    1984-08-01

    A pulse test is conducted by creating a series of short-time pressure transients in an active (pulsing) well and recording the observed pressure response at an observation (responding) well. Using the pressure response and flow rate data, the transmissivity and storativity of the tested formation can be determined. Like any other pressure transient data, the pulse-test response is significantly influenced by wellbore storage and skin effects. The purpose of this research is to examine the influence of wellbore storage and skin effects on interference testing in general and on pulse-testing in particular, and to present the type curves and procedures for designing and analyzing pulse-test data when wellbore storage and skin effects are active at either the responding well or the pulsing well. A mathematical model for interference testing was developed by solving the diffusivity equation for radial flow of a single-phase, slightly compressible fluid in an infinitely large, homogeneous reservoir. When wellbore storage and skin effects are present in a pulse test, the observed response amplitude is attenuated and the time lag is inflated. Consequently, neglecting wellbore storage and skin effects in a pulse test causes the calculated storativity to be over-estimated and the transmissivity to be under-estimated. The error can be as high as 30%. New correlations and procedures are developed for correcting the pulse response amplitude and time lag for wellbore storage effects. Using these correlations, it is possible to correct the wellbore storage-dominated response amplitude and time lag to within 3% of their expected values without wellbore storage, and in turn to calculate the corresponding transmissivity and storativity. Worked examples are presented to illustrate how to use the new correction techniques. 45 references.

  17. Geomechanical analysis to predict the oil leak at the wellbores in Big Hill Strategic Petroleum Reserve

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung Yoon

    2014-02-01

    Oil leaks were found in wellbores of Caverns 105 and 109 at the Big Hill Strategic Petroleum Reserve site. According to the field observations, two instances of casing damage occurred at the depth of the interbed between the caprock bottom and salt top. A three dimensional finite element model, which contains wellbore element blocks and allows each cavern to be configured individually, is constructed to investigate the wellbore damage mechanism. The model also contains element blocks to represent interface between each lithology and a shear zone to examine the interbed behavior in a realistic manner. The causes of the damaged casing segments are a result of vertical and horizontal movements of the interbed between the caprock and salt dome. The salt top subsides because the volume of caverns below the salt top decrease with time due to salt creep closure, while the caprock subsides at a slower rate because the caprock is thick and stiffer. This discrepancy yields a deformation of the well. The deformed wellbore may fail at some time. An oil leak occurs when the wellbore fails. A possible oil leak date of each well is determined using the equivalent plastic strain failure criterion. A well grading system for a remediation plan is developed based on the predicted leak dates of each wellbore.

  18. Estimation of Wellbore and Formation Temperatures during the Drilling Process under Lost Circulation Conditions

    Directory of Open Access Journals (Sweden)

    Mou Yang

    2013-01-01

    Full Text Available Significant change of wellbore and surrounding formation temperatures during the whole drilling process for oil and gas resources often leads by annulus fluid fluxes into formation and may pose a threat to operational security of drilling and completion process. Based on energy exchange mechanisms of wellbore and formation systems during circulation and shut-in stages under lost circulation conditions, a set of partial differential equations were developed to account for the transient heat exchange process between wellbore and formation. A finite difference method was used to solve the transient heat transfer models, which enables the wellbore and formation temperature profiles to be accurately predicted. Moreover, heat exchange generated by heat convection due to circulation losses to the rock surrounding a well was also considered in the mathematical model. The results indicated that the lost circulation zone and the casing programme had significant effects on the temperature distributions of wellbore and formation. The disturbance distance of formation temperature was influenced by circulation and shut-in stages. A comparative perfection theoretical basis for temperature distribution of wellbore-formation system in a deep well drilling was developed in presence of lost circulation.

  19. Mono pile foundation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lyngesen, S.; Brendstrup, C.

    1997-02-01

    The use of mono piles as foundations for maritime structures has been developed during the last decades. The installation requirements within the offshore sector have resulted in equipment enabling driving of piles up to 3-4 m to large penetration depths. The availability of this equipment has made the use of large mono piles feasible as foundations for structures like wind turbines. The mono pile foundations consists of three parts; the bare pile, a conical transition and a boat landing. All parts are prefitted at the yard in order to minimise the installation work that has to be carried out offshore. The study of a mono pile foundations for a 1.5 MW wind turbine has been conducted for two locations, Horns Rev and Roedsand. Three different water depths: 5, 8 and 11 m have been investigated in the study. The on-site welding between pile and conical transition is performed by an automatic welding machine. Final testing and eventually repair of the weld are conducted at least 16 hours after welding. This is followed by final installation of J-tube, tie-in to subsea cables and installation of the impressed current system for corrosive protection of the mono pile. The total cost for procurement and installation of the mono pile using the welded connection is estimated. The price does not include procurement and installation of access platform and boat landing. These costs are estimated to 250.000 DKK. Depending on water depth the cost of the pile ranges from 2,2 to 2,7 million DKK. Procurement and fabrication of the pile are approx. 75% of the total costs. The remaining 25% are due to installation. The total costs are very sensitive to the unit price of pile steel. During the project it became obvious that ice load has a very large influence on the dimensions of the mono pile. (EG)

  20. Application of inertial navigation to wellbore positional surveying

    Energy Technology Data Exchange (ETDEWEB)

    Watts, A.C.

    1982-06-01

    There is an increasing need for higher accuracy in wellbore directional and positional surveying than is currently available using conventional techniques. Among the factors contributing to this need are closed interspacing of wells particularly from offshore platforms, deeper and more highly deviated wells, smaller target formations and the requirement for rapid drilling of relief wells in the case of blowouts. The application of inertial navigation system (INS) of suitable size and cost for this type of application is not inherently accurate enough to offer significant improvements in well-surveying accuracy. Techniques to improve accuracy are, in general, based on the fact that the dynamics associated with the propagation of the navigator errors are very well known. Inertial systems are routinely aided using external data from a number of sources. Such aiding may take the form of an external position or velocity measurement which is compared to the position or velocity indicated by the navigator. Kalman filter theory provides a convenient formulation for generation of a minimum variance estimate of the state vector of a linear system. The theory may be extended to the nonlinear case through the use of linearization about a state trajectory. This approach is currently seeing wide use in aiding of inertial navigation systems. The approach proposed here would use the Kalman filter formulation for estimation of the INS errors and updating of the navigator. This formulation also provides a structure for estimation of various instrument parameters which should improve system performance.

  1. Investigation of Possible Wellbore Cement Failures During Hydraulic Fracturing Operations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jihoon; Moridis, George

    2014-11-01

    We model and assess the possibility of shear failure, using the Mohr-Coulomb model ? along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, low cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a high-quality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.

  2. Model based monitoring of wellbore hydraulics for abnormal event detection

    Energy Technology Data Exchange (ETDEWEB)

    Todorov, Dimitar; Fruhwirth, Rudolf K. [Thonhauser Data Engineering GmbH, Leoben (Austria); Thonhauser, Gerhard [Montanuniversitaet Leoben (Austria)

    2013-03-15

    With the increasing demand for energy in the last decades, the petroleum industry was forced to push the limits to levels that have never been reached before. Exploring very deep waters, drilling under varying conditions of extreme pressure and temperature and dealing with issues, which involve a new level of understanding, are challenges, which need to be overcome in order to safely and successfully accomplish the planned goals. Operating under such circumstances obligates the driller to be extremely precise in his actions. Even with the driller's extensive experience and training, the possible reaction time is in some cases extremely short. This article discusses the reasons for automatic trouble event recognition systems in the drilling process and how these affect the drilling operations and optimization processes. In this respect a concept of a real time hydraulic monitor will be developed helping the driller to visualize calculations in a plot, showing the pump limitations, the limitations due to the formation fracture gradient and the hole cleaning requirements. Additionally, taking into account the complete wellbore hydraulics and introducing various well behavior models and different algorithms, the system is capable of operating as a real-time indicator for undesired downhole events. (orig.)

  3. Fluid-solid coupling model for studying wellbore instability in drilling of gas hydrate bearing sediments

    Institute of Scientific and Technical Information of China (English)

    程远方; 李令东; 崔青

    2013-01-01

    As the oil or gas exploration and development activities in deep and ultra-deep waters become more and more, encountering gas hydrate bearing sediments (HBS) is almost inevitable. The variation in temperature and pressure can destabilize gas hydrate in nearby formation around the borehole, which may reduce the strength of the formation and result in wellbore instability. A non-isothermal, transient, two-phase, and fluid-solid coupling mathematical model is proposed to simulate the complex stability performance of a wellbore drilled in HBS. In the model, the phase transition of hydrate dissociation, the heat exchange between drilling fluid and formation, the change of mechanical and petrophysical properties, the gas-water two-phase seepage, and its interaction with rock deformation are considered. A finite element simulator is developed, and the impact of drilling mud on wellbore instability in HBS is simulated. Results indicate that the re-duction in pressure and the increase in temperature of the drilling fluid can accelerate hydrate decomposition and lead to mechanical properties getting worse tremendously. The cohesion decreases by 25% when the hydrate totally dissociates in HBS. This easily causes the wellbore instability accordingly. In the first two hours after the formation is drilled, the regions of hydrate dissociation and wellbore instability extend quickly. Then, with the soaking time of drilling fluid increasing, the regions enlarge little. Choosing the low temperature drilling fluid and increasing the drilling mud pressure appropriately can benefit the wellbore stability of HBS. The established model turns out to be an efficient tool in numerical studies of the hydrate dissociation behavior and wellbore stability of HBS.

  4. A Wellbore Stability Model for a Deviated Well in a Transversely Isotropic Formation Considering Poroelastic Effects

    Science.gov (United States)

    Liu, Ming; Jin, Yan; Lu, Yunhu; Chen, Mian; Hou, Bing; Chen, Wenyi; Wen, Xin; Yu, Xiaoning

    2016-09-01

    To analyse wellbore stability phenomena when drilling through a transversely isotropic formation such as shale, a wellbore stability model is developed based on the coordinate transformation method and complex variable elasticity theory. In order to comprehensively consider the anisotropies in the transversely isotropic formation, the model includes the followings: 1. the elastic anisotropy due to the sedimentation effect and naturally developed fractures and 2. the strength anisotropy due to the poor cementation between bedding planes and natural fractures. The model is further generalized by accounting for an arbitrary wellbore trajectory under an arbitrary in situ stress orientation. Next, the model is used in a parametric study that includes factors such as elastic anisotropy, strength anisotropy, multiple weak planes, in situ stress anisotropy, and poroelastic anisotropy, all of which can have a great influence on wellbore stability. Finally, a correction for a frequently used failure criterion has been made to ensure that the newly developed model is comprehensive and accurate for wellbore stability analyses in highly heterogeneous formations.

  5. On the analysis of well test data influenced by wellbore storage, skin, asnd bottomwater drive

    Energy Technology Data Exchange (ETDEWEB)

    Chu, W.C.; Chen, J.C.; Raghavan, R.; Reynolds, A.C.

    1984-11-01

    The combined influence of wellbore storage, wellbore damage, and partial penetration on the analysis of pressure data is discussed. The effect of a gas cap or bottomwater aquifer (constant pressure boundary) also is documented. The authors demonstrate that the magnitude of the wellbore storage constant dictates the type and amount of information that can be gleaned from a pressure test during the storage dominated period. For small values of the dimensionless storage constant and large values of dimensionless well length, the flow capacity of the perforated (open) interval and the skin factor, which reflects impediments to flow around the sand face, can be determined from data affected by wellbore storage. This information can be obtained from the wellbore storage type curves (the complete penetration solutions) available in the literature. Values of the dimensionless well length and storage constant for which this information can be obtained are specified in the paper. For other cases, the flow capacity of the entire interval and the total skin factor can be estimated. Again, storage type curves for the complete penetration solutions can be used to obtain this information if both boundaries are sealed. If one of the boundaries is at a constant pressure (water drive or gas cap), then the new solution presented in this paper should be used.

  6. Simulation of a SAGD well blowout using a reservoir-wellbore coupled simulator

    Energy Technology Data Exchange (ETDEWEB)

    Walter, J.; Vanegas, P.; Cunha, L.B. [Alberta Univ., Edmonton, AB (Canada); Worth, D.J. [C-FER Technologies, Edmonton, AB (Canada); Crepin, S. [Petrocedeno, Caracas (Venezuela)

    2008-10-15

    Single barrier completion systems are typically used in SAGD projects due to the lack of equipment suitable for high temperature SAGD downhole environments. This study used a wellbore and reservoir coupled thermal simulator tool to investigate the blowout behaviour of a steam assisted gravity drainage (SAGD) well pair when the safety barrier has failed. Fluid flow pressure drop through the wellbore and heat losses between the wellbore and the reservoir were modelled using a discretized wellbore option and a semi-analytical model. The fully coupled mechanistic model accounted for the simultaneous transient pressure and temperature variations along the wellbore and the reservoir. The simulations were used to predict flowing potential and fluid compositions of both wells in a SAGD well pair under various flowing conditions. Blowout scenarios were created for 3 different points in the well pair's life. Three flow paths during the blowout were evaluated for both the production and injection wells. Results of the study were used to conduct a comparative risk assessment between a double barrier and a single barrier completion. The modelling study confirmed that both the injection and production wells had the potential for blowouts lasting significant periods of time, with liquid rates over 50 times the normal production liquid rates. The model successfully predicted the blowout flow potential of the SAGD well pairs. 8 refs., 3 tabs., 18 figs.

  7. Subsurface fracture mapping from geothermal wellbores. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hartenbaum, B.A.; Rawson, G.

    1983-08-01

    To advance the state-of-the-art in Hot Dry Rock technology, and evaluation is made of (1) the use of both electromagnetic and acoustic radar to map far-field fractures, (2) the use of more than twenty different conventional well logging tools to map borehole-fracture intercepts, (3) the use of magnetic dipole ranging to determine the relative positions of the injection well and the production well within the fractured zone, (4) the use of passive microseismic methods to determine the orientation and extent of hydraulic fractures, and (5) the application of signal processing techniques to fracture mapping including tomography, holography, synthetic aperture, image reconstruction, and the relative importance of phase and amplitude information. It is found that according to calculations, VHF backscatter radar has the potential for mapping fractures within a distance of 50 +- 20 meters from the wellbore. A new technique for improving fracture identification is presented. The range of acoustic radar is five to seven times greater than that of VHF radar when compared on the basis of equal resolution, i.e., equal wavelengths. Analyses of extant data indicate that when used synergistically the (1) caliper, (2) resistivity dipmeter, (3) televiewer, (4) television, (5) impression packer, and (6) acoustic transmission are useful for mapping borehole-fracture intercepts. A new model of hydraulic fracturing is presented which indicates that a hydraulic fracture is dynamically unstable; consequently, improvements in locating the crack tip may be possible. The importance of phase in signal processing is stressed and those techniques which employ phase data are emphasized for field use.

  8. The wellbore pressure response in naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, A.C.; Chang, W.L.

    1983-10-01

    Recently a new flow regime has been identified for pressure drawdown or buildup data obtained from a well producing a naturally fractured reservoir. During the time period corresponding to this new flow regime, a semilog plot of pressure versus time exhibits a semilog straight line with slope equal to m/2, where m is the slope of both the ''early and late time'' semilog straight lines predicted by the Warren and Root model. The identification of this intermediate time semilog straight line means that pressure data may exhibit as many as three semilog straight lines. A virtually complete analysis of well test pressure data is possible when the data exhibits two or more of the three possible straight lines. In this work we present type curves which can be used to obtain a virtually complete analysis of pressure data when only one of the three semilog straight lines is reflected by the data. Analytical work on the pressure response in a naturally fractured reservoir requires the assumption of a matrix-fracture geometry. One model that has frequently been used assumes that a naturally fractured reservoir is equivalent to a system of plane horizontal fractures. The use of this model suggests that the pressure response should be similar to the pressure response in a two-layer reservoir. In this work, the authors establish the conditions under which the pressure response in a two-layer reservoir with crossflow between the layers will be identical to the pressure response in a naturally fractured reservoir. The twolayer analogue provides information on the well response when the matrix feeds directly into the wellbore. In addition, the authors consider the economic feasibility of stimulating the ''matrix layer''.

  9. Festival nimega Mono / Ivar Sakk

    Index Scriptorium Estoniae

    Sakk, Ivar, 1962-

    2015-01-01

    Haapsalu graafilise disaini festival Haapsalu Linnagaleriis: sisaldab ülevaate- ja teemanäitust ning väikest sümpoosioni. Temaatilise aastanäituse motiiv on "MONO". Plakateid on ka välismaa tegijatelt. Kuraator Marko Kekishev

  10. Improving the accuracy and reliability of MWD/magnetic-Wellbore-Directional surveying in the barents sea

    DEFF Research Database (Denmark)

    Edvardsen, I.; Nyrnes, E.; Johnsen, M. G.;

    2014-01-01

    , and the effect of the latter is increased because of diminished value of the magnetic horizontal component. Wellbore directional surveying for operations on the continental shelf in the North Sea and the Norwegian Sea rely on wellestablishedprocedures for near-real-time magnetic monitoring by use of onshore...... of nonmagnetic steel in the bottomhole assembly (BHA). To maintain azimuth uncertaintyat an acceptable level in northern areas, it is crucial that wellbore-directional-surveying requirements are given high priority and considered early during well planning. During the development phase of an oil and gas field......, the planned wells must be assigned adequate positional-uncertainty models and, if possible, be designed in a direction that minimizes the wellbore directional uncertainty. ©2014 Society of Petroleum Engineers....

  11. A feedback-based inverse heat transfer method to estimate unperturbed temperatures in wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa-Paredes, Gilberto [Area de Ingenieria en Recursos Energeticos, Universidad Autonoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Mexico D.F. 09340 (Mexico); Espinosa-Martinez, Erick G. [Retorno Quebec 6, Col. Burgos de Cuernavaca 62580, Temixco, Mor. (Mexico)

    2009-01-15

    This paper presents a feedback-based strategy to solve an inverse heat transfer problem for the estimation of unperturbed formation temperatures (UFT) from measured temperatures in wellbores. The feedback function uses the error between the measured and estimated temperatures during the shut-in process. Thus, an inverse heat transfer problem was solved in this way since the UFT represents the unknown initial conditions and the measured temperatures in the wellbore represents the particular solution of the PDE'S governing the heat transfer process in the formation and in the wellbore system. The performance of the method is illustrated via numerical simulations of two wells: (a) oil well FE-1227 from the Gulf of Mexico maritime zone and (b) well CP-0512 from Cerro Prieto Mexican geothermal field. (author)

  12. Equilibrium equations for nonlinear buckling analysis of drill-strings in 3D curved well-bores

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    With the development of drilling technology, the oil/gas well has evolved from its early vertical straight form to the inclined, horizontal, plane curved, or even 3D curved well-bore. Understanding of the buck- ling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation. Therefore, equilibrium equations for analyzing the buckling behavior of a drill-string in a 3D curved well-bore are required. Based on Love’s equilibrium equations for a curved and twisted rod in space, a set of equi- librium equations for the nonlinear buckling analysis of a drill-string in a 3D curved well-bore are de- rived by introducing a radial constraint of the well-bore. The proposed formulae can account for the well curvature and tortuosity. Thus, it can be used to analyze the buckling behaviors of a drill-string constrained in a well-bore and subjected to axial compression, torsion at its upper end, and gravity simultaneously. It is worth noting that the existing equations in the literature for a drill-string in a straight and plane curved well-bore with a constant curvature are a special case of the proposed model. Thus, the present model can provide a theoretical basis for the nonlinear buckling analysis of a drill-string constrained in a 3D curved well-bore.

  13. Equilibrium equations for nonlinear buckling analysis of drill-strings in 3D curved well-bores

    Institute of Scientific and Technical Information of China (English)

    TAN MeiLan; GAN LiFei

    2009-01-01

    With the development of drilling technology, the oil/gas well has evolved from its early vertical straight form to the inclined, horizontal, plane curved, or even 3D curved well-bore. Understanding of the buck-ling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation. Therefore, equilibrium equations for analyzing the buckling behavior of a drill-string in a 3D curved well-bore are required. Based on Love's equilibrium equations for a curved and twisted rod in space, s set of equi-librium equations for the nonlinear buckling analysis of a drill-string in a 3D curved well-bore are de-rived by introducing a radial constraint of the well-bore. The proposed formulae can account for the well curvature and tortuosity. Thus, it can be used to analyze the buckling behaviors of a drill-string constrained in a well-bore and subjected to axial compression, torsion at its upper end, and gravity simultaneously. It is worth noting that the existing equations in the literature for a drill-string in a straight and plane curved well-bore with a constant curvature are a special case of the proposed model. Thus, the present model can provide s theoretical basis for the nonlinear buckling analysis of a drill-string constrained in a 3D curved well-bore.

  14. Interpreting stem diameter changes

    Science.gov (United States)

    Hölttä, T.; Sevanto, S.; Nikinmaa, E.

    2009-12-01

    Detecting phloem transport in stem diameter changes Teemu Hölttä1, Sanna Sevanto2, Eero Nikinmaa1 1Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland 2Department of Physics, P.O. Box 48, FIN-00014 University of Helsinki, Finland Introduction The volume of living cells and xylem conduits vary according to pressures they are subjected to. Our proposition is that the behavior of the inner bark diameter variation which cannot be explained by changes in xylem water status arise from changes in the osmotic concentration of the phloem and cambial growth. Materials and methods Simultaneous xylem and stem diameter measurements were conducted between June 28th to October 4th 2006 in Southern Finland on a 47-year old, 15 meter tall, Scots pine tree (DBH 15 cm) at heights of 1.5 and 10 meters. The difference between the measured inner bark diameter and the inner bark diameter predicted from xylem diameter change with a simple model (assuming there was no change in the osmotic concentration of the phloem) is hypothesized to give the changes in the osmotic concentration of the inner bark. The simple model calculates the radial water exchange between the xylem and phloem driven by the water potential changes in the xylem. Results and Discussion The major signal in the inner bark diameter was the transpiration rate as assumed, but also a signal arising from the change in the osmotic concentration (Fig 1a). The predicted osmotic concentration of the phloem typically increased during the afternoon due to the loading of photosynthesized sugars to the phloem. Inner bark osmotic concentration followed the photosynthesis rate with a 3 and 4 hour time-lag at the top and base, respectively (Fig 1b). The connection between photosynthesis and the predicted change in phloem osmotic concentration was stronger in the upper part of the tree compared to lower part. The changes in the predicted osmotic concentration were not similar every day, indicating that

  15. Fracture healing and transport properties of wellbore cement in the presence of supercritical CO2

    NARCIS (Netherlands)

    Liteanu, E.; Spiers, C.J.

    2011-01-01

    This paper investigates the process and rate of carbonation reaction of Class A wellbore cement exposed to CO2-saturated solution at confined conditions similar to those employed in geological storage of CO2. The main goal was to investigate whether reaction improves or degrades the sealing/healing

  16. Effect of CO2-induced reactions on the mechanical behaviour of fractured wellbore cement

    NARCIS (Netherlands)

    Wolterbeek, T.K.T.; Hangx, S.J.T.; Spiers, C.J.

    2016-01-01

    Geomechanical damage, such as fracturing of wellbore cement, can severely impact well integrity in CO2 storage fields. Chemical reactions between the cement and CO2-bearing fluids may subsequently alter the cement’s mechanical properties, either enhancing or inhibiting damage accumulation during ong

  17. Wellbore Models GWELL, GWNACL, and HOLA User's Guide

    Energy Technology Data Exchange (ETDEWEB)

    Aunzo, Z.P.; Bjornsson, G.; Bodvarsson, G.S.

    1991-10-01

    This report describes three multi-component, multi-feedzone geothermal wellbore simulators developed. These simulators reproduce the measured flowing temperature and pressure profiles in flowing wells and determine the relative contribution, fluid properties (e.g. enthalpy, temperature) and fluid composition (e.g. CO{sub 2}, NaCl) of each feedzone for a given discharge condition. The three related wellbore simulators that will be discussed here are HOLA, GWELL and GWNACL. HOLA is a multi-feedzone geothermal wellbore simulator for pure water, modified after the wellbore simulator developed by Bjornsson, 1987 and can now handle deviated wells. The other two simulators GWELL (see also Aunzo, 1990) and GWNACL are modified versions of HOLA that can handle H{sub 2}O-CO{sub 2} and H{sub 2}O-NaCl systems, respectively. These simulators can handle both single and two-phase flows in vertical and inclined pipes and calculate the flowing temperature and pressure profiles in the well. The simulators solve numerically the differential equations that describe the steady-state energy, mass and momentum flow in a pipe. The codes allow for multiple feedzones, variable grid spacing and well radius. These codes were developed using FORTRAN language on the UNIX system.

  18. Wellbore models GWELL, GWNACL, and HOLA: User's guide

    Energy Technology Data Exchange (ETDEWEB)

    Aunzo, Z.P. (PNOC Energy Development Corp., Metro Manila (Philippines). Geothermal Div.); Bjornsson, G. (Icelandic National Energy Authority, Reykjavik (Iceland)); Bodvarsson, G.S. (Lawrence Berkeley Lab., CA (United States))

    1991-10-01

    This report describes three multi-component, multi-feedzone geothermal wellbore simulators developed. These simulators reproduce the measured flowing temperature and pressure profiles in flowing wells and determine the relative contribution, fluid properties (e.g., enthalpy, temperature) and fluid composition (e.g. CO{sub 2}, NaCl) of each feedzone for a given discharge condition. The three related wellbore simulators that will be discussed here are HOLA, GWELL and GWNACL. HOLA is a multi-feedzone geothermal wellbore simulator for pure water, modified after the wellbore simulator developed by Bjornsson, 1987 and can now handle deviated wells. The other two simulators GWELL and GWNACL are modified versions of HOLO that can handle H{sub 2}O CO{sub 2} and H{sub 2}O-NaCl systems, respectively. These simulators can handle both single and two-phase flows in vertical and inclined pipes and calculate the flowing temperature and pressure profiles in the well. The simulators solve numerically the differential equations that describe the steady-state energy, mass and momentum flow in a pipe. The codes allow for multiple feedzones, variable grid spacing and well radius. Theses codes were developed using FORTRAN language on the UNIX system.

  19. Trajectory Control:Directional MWD Inversely New Wellbore Positioning Accuracy Prediction Method

    Institute of Scientific and Technical Information of China (English)

    Ahmed Abd Alaziz Ibrahim; Tagwa Ahmed Musa

    2004-01-01

    The deviation control of directional drilling is essentially the controlling of two angles of the wellbore actually drilled, namely, the inclination and azimuth. In directional drilling the bit trajectory never coincides exactly with the planned path, which is usually a plane curve with straight, building, holding, and dropping sections in succession. The drilling direction is of course dependant on the direction of the resultant forces acting on the bit and it is quite a tough job to hit the optimum target at the hole bottom as required. The traditional passive methods for correcting the drilling path have not met the demand to improve the techniques of deviation control. A method for combining wellbore surveys to obtain a composite, more accurate well position relies on accepting the position of the well from the most accurate survey instrument used in a given section of the wellbore. The error in each position measurement is the sum of many independent root sources of error effects. The relationship between surveys and other influential factors is considered, along with an analysis of different points of view. The collaborative work describes, establishes a common starting point of wellbore position uncertainty model, definition of what constitutes an error model, mathematics of position uncertainty calculation and an error model for basic directional service.

  20. Optimisation of the Near-Wellbore Geometry of Hydraulic Fractures Propagating from Cased Perforated Completions

    NARCIS (Netherlands)

    van de Ketterij, R.G.

    2001-01-01

    Hydraulic fracturing is a technique frequently used to stimulate the production of an oil or gas well by creating a fracture in the porous rock around the wellbore. The success of a hydraulic fracture treatment depends heavily on the created fracture geometry. The optimum situation arises when a sin

  1. Prediction of natural gas hydrate formation region in wellbore during deep- water gas well testing

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-yuan; SUN Bao-jiang; WANG Xue-rui; ZHANG Zhen-nan

    2014-01-01

    Wellbore temperature field equations are established with considerations of the enthalpy changes of the natural gas during the deep-water gas well testing. A prediction method for the natural gas hydrate formation region during the deep-water gas well testing is proposed, which combines the wellbore temperature field equations, the phase equilibrium conditions of the natural gas hydrate formation and the calculation methods for the pressure field. Through the sensitivity analysis of the parameters that affect the hydrate formation region, it can be concluded that during the deep-water gas well testing, with the reduction of the gas production rate and the decrease of the geothermal gradient, along with the increase of the depth of water, the hydrate formation region in the wellbore enlarges, the hydrate formation regions differ with different component contents of natural gases, as compared with the pure methane gas, with the increase of ethane and propane, the hydrate formation region expands, the admixture of inhibitors, the type and the concentrations of which can be optimized through the method proposed in the paper, will reduce the hydrate formation region, the throttling effect will lead to the abrupt changes of temperature and pressure, which results in a variation of the hydrate formation region, if the throttling occurs in the shallow part of the wellbore, the temperature will drop too much, which enlarges the hydrate formation region, otherwise, if the throttling occurs in the deep part of the wellbore, the hydrate formation region will be reduced due to the decrease of the pressure.

  2. Determination of Diffusion Profiles in Altered Wellbore Cement Using X-ray Computed Tomography Methods

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Harris E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Walsh, Stuart D. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DuFrane, Wyatt L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Carroll, Susan A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-06-17

    The development of accurate, predictive models for use in determining wellbore integrity requires detailed information about the chemical and mechanical changes occurring in hardened Portland cements. X-ray computed tomography (XRCT) provides a method that can nondestructively probe these changes in three dimensions. Here, we describe a method for extracting subvoxel mineralogical and chemical information from synchrotron XRCT images by combining advanced image segmentation with geochemical models of cement alteration. The method relies on determining “effective linear activity coefficients” (ELAC) for the white light source to generate calibration curves that relate the image grayscales to material composition. The resulting data set supports the modeling of cement alteration by CO2-rich brine with discrete increases in calcium concentration at reaction boundaries. The results of these XRCT analyses can be used to further improve coupled geochemical and mechanical models of cement alteration in the wellbore environment.

  3. U.S. Geological Survey Combined Well-Bore Flow and Depth-Dependent Water Sampler

    Science.gov (United States)

    Izbicki, John A.; Christensen, Allen H.; Hanson, Randall T.; Martin, Peter; Crawford, Steven M.; Smith, Gregory A.

    1999-01-01

    The U.S. Geological Survey has developed a combined well-bore flow and depth-dependent sample collection tool. It is suitable for use in existing production wells having limited access and clearances as small as 1 inch. The combination of well-bore flow and depth-dependent water-quality data is especially effective in assessing changes in aquifer properties and water quality with depth. These are direct measures of changes in well yield and ground-water quality with depth under actual operating conditions. Combinations of other geophysical tools capable of making these measurements, such as vertical-axis current meters used with wire-line samplers, are commercially available but these tools are large and can not easily enter existing production wells.

  4. Offshore wellbore stability analysis based on fully coupled poro-thermo-elastic theory

    Science.gov (United States)

    Cao, Wenke; Deng, Jingen; Yu, Baohua; Liu, Wei; Tan, Qiang

    2017-03-01

    Drilling-induced tensile fractures are usually caused when the weight of mud is too high, and the effective tangential stress becomes tensile. It is thus hard to explain why tensile fractures are distributed along the lower part of a hole in an offshore exploration well when the mud weight is low. According to analysis, the reason could be the thermal effect, which cannot be ignored because of the drilling fluid and the cooling action of sea water during circulation. A heat transfer model is set up to obtain the temperature distribution of the wellbore and its formation by the finite difference method. Then, fully coupled poro-thermo-elastic theory is used to study the pore pressure and effective stress around the wellbore. By comparing it with both poroelastic and elastic models, it is indicated that the poroelastic effect is dominant at the beginning of circulation and inhibits tensile fractures from forming; then, the thermal effect becomes more important and decreases the effective tangential stress with the passing of time, so the drilling fluid and the cooling effect of sea water can cause tensile fractures to happen. Meanwhile, tensile fractures are shallow and not likely to lead to mud leakage with lower mud weight, which agrees with the actual drilling process. On the other hand, the fluid cooling effect could increase the strength of the rock and reduce the likelihood of shear failure, which would be beneficial for wellbore stability. So, the thermal effect cannot be neglected in offshore wellbore stability analysis, and mud weight and borehole exposure time should be controlled in the case of mud loss.

  5. Wellbore Stability in Oil and Gas Drilling with Chemical-Mechanical Coupling

    Directory of Open Access Journals (Sweden)

    Chuanliang Yan

    2013-01-01

    Full Text Available Wellbore instability in oil and gas drilling is resulted from both mechanical and chemical factors. Hydration is produced in shale formation owing to the influence of the chemical property of drilling fluid. A new experimental method to measure diffusion coefficient of shale hydration is given, and the calculation method of experimental results is introduced. The diffusion coefficient of shale hydration is measured with the downhole temperature and pressure condition, then the penetration migrate law of drilling fluid filtrate around the wellbore is calculated. Furthermore, the changing rules of shale mechanical properties affected by hydration and water absorption are studied through experiments. The relationships between shale mechanical parameters and the water content are established. The wellbore stability model chemical-mechanical coupling is obtained based on the experimental results. Under the action of drilling fluid, hydration makes the shale formation softened and produced the swelling strain after drilling. This will lead to the collapse pressure increases after drilling. The study results provide a reference for studying hydration collapse period of shale.

  6. Coalbed Methane Production System Simulation and Deliverability Forecasting: Coupled Surface Network/Wellbore/Reservoir Calculation

    Directory of Open Access Journals (Sweden)

    Jun Zhou

    2017-01-01

    Full Text Available As an unconventional energy, coalbed methane (CBM mainly exists in coal bed with adsorption, whose productivity is different from conventional gas reservoir. This paper explains the wellbore pressure drop, surface pipeline network simulation, and reservoir calculation model of CBM. A coupled surface/wellbore/reservoir calculation architecture was presented, to coordinate the gas production in each calculation period until the balance of surface/wellbore/reservoir. This coupled calculation method was applied to a CBM field for predicting production. The daily gas production increased year by year at the first time and then decreased gradually after several years, while the daily water production was reduced all the time with the successive decline of the formation pressure. The production of gas and water in each well is almost the same when the structure is a star. When system structure is a dendritic surface system, the daily gas production ranked highest at the well which is the nearest to the surface system collection point and lowest at the well which is the farthest to the surface system collection point. This coupled calculation method could be used to predict the water production, gas production, and formation pressure of a CBM field during a period of time.

  7. Problems in the wellbore integrity of a shale gas horizontal well and corresponding countermeasures

    Directory of Open Access Journals (Sweden)

    Zhonglan Tian

    2015-12-01

    Full Text Available In the Changning–Weiyuan national shale gas demonstration area, SW Sichuan Basin, the wellbore integrity damage occurs in some shale gas wells and has direct effect on the gas production rate of single shale gas horizontal well. After statistics analysis was performed on the problems related with wellbore integrity, such as casing damage, casing running difficulty and cement sheath blow-by, the multi-factor coupling casing stress calculation and evaluation mode laws established. Then study was conducted on the influential mechanism of multi-factor coupling (temperature effect, casing bending and axial pressure on casing damage. The shale slip mechanism and its relationship with casing sheared formation were analyzed by using the Mohr–Coulomb criterion. Inversion analysis was performed on the main controlling factors of casing friction by using the developed casing hook load prediction and friction analysis software. And finally, based on the characteristics of shale gas horizontal wells, wellbore integrity control measures were proposed in terms of design and construction process, so as to improve the drilling quality (DQ. More specifically, shale gas well casing design calculation method and check standard were modified, well structure and full bore hole trajectory design were optimized, drilling quality was improved, cement properties were optimized and cement sealing integrity during fracturing process was checked. These research findings are significant in the design and management of future shale gas borehole integrity.

  8. Dynamic alterations in wellbore cement integrity due to geochemical reactions in CO2-rich environments

    Science.gov (United States)

    Cao, Peilin; Karpyn, Zuleima T.; Li, Li

    2013-07-01

    The interaction between wellbore cement and CO2 has the potential to alter cement properties and form preferential leakage pathways during geological carbon sequestration. This work investigates changes in wellbore cement integrity during continuous flooding of CO2-saturated brine. We created composite cement-sandstone core samples with a continuous gap in the cement zone in order to represent defects such as fractures and voids in wellbore cement. Volumetric and structural changes in the cement zone were monitored and quantified using X-ray Micro-Computed Tomography imaging. During an 8 day dynamic flow-through period, the fracture/void aperture increased significantly, whereas the host sandstone remained unaltered. The void volume increased at a faster rate in the early stage of the flow-through period than it did toward the end of the period. Compared to the apertures close to the core outlet, those located near the core inlet experienced more severe cement degradation, accompanied by a decrease in specific surface area, constituting evidence of a smoothing effect. Contrary to previous observations of the self-healing behavior of cement fractures, the in situ permeability on a parallel experiment increased by a factor of 8 after 10 days of flooding. Findings from this work will provide valuable insights applicable to the development of predictive models and for risk assessment under conditions relevant to CO2 sequestration.

  9. Quasi-steady model for predicting temperature of aqueous foams circulating in geothermal wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Blackwell, B.F.; Ortega, A.

    1983-01-01

    A quasi-steady model has been developed for predicting the temperature profiles of aqueous foams circulating in geothermal wellbores. The model assumes steady one-dimensional incompressible flow in the wellbore; heat transfer by conduction from the geologic formation to the foam is one-dimensional radially and time-dependent. The vertical temperature distribution in the undisturbed geologic formation is assumed to be composed of two linear segments. For constant values of the convective heat-transfer coefficient, a closed-form analytical solution is obtained. It is demonstrated that the Prandtl number of aqueous foams is large (1000 to 5000); hence, a fully developed temperature profile may not exist for representative drilling applications. Existing convective heat-transfer-coefficient solutions are adapted to aqueous foams. The simplified quasi-steady model is successfully compared with a more-sophisticated finite-difference computer code. Sample temperature-profile calculations are presented for representative values of the primary parameters. For a 5000-ft wellbore with a bottom hole temperature of 375{sup 0}F, the maximum foam temperature can be as high as 300{sup 0}F.

  10. A Simple Data Analysis Method for a Pumping Test with Skin and Wellbore Storage Effects

    Directory of Open Access Journals (Sweden)

    Chia-Shyun Chen and Chuan-Gui Lan

    2009-01-01

    Full Text Available In a pumping test conducted in a con fined aquifer in northern Taiwan, drawdown in the observation well was subject to wellbore storage of its own and the combined effect of wellbore storage and skin of the nearby pumping well. For such a complicated pumping test condition, the appropriate well hydraulics solutions are complicated in mathematics and involve five unknown a priori parameters; namely, the aquifer transmissivity, the aquifer storage coefficient, the skin factor of the pumping well, and the wellbore storage co efficients of the pumping and observation wells. The conventional trial-and-er ror procedure for a simul taneous determination of these five parameters is not easy to apply. Here, a simple data analysis method is de veloped, which takes advantage of the late-time characteristics of drawdown data and the late-time asymptotic behavior of the appropriate wellhy draulics solutions. As a re sult, some currently available graphic techniques are proven us ful for the determination of these parameters. Validity of this approach is verified by the excellent agree ment between the calculated drawdown using the appropriate well hydraulics solutions with the parameter estimates obtained from the field drawdown data.

  11. Experimental and Computational Studies of Coupled Geomechanical and Hydrologic Processes in Wellbore Systems (Invited)

    Science.gov (United States)

    Carey, J. W.; Mori, H.; Porter, M. L.; Lewis, K. C.; Kelkar, S.

    2013-12-01

    Potential leakage from wells is an important issue in the protection of groundwater resources, CO2 sequestration, and hydraulic fracturing. The first defense in all of these applications is a properly constructed well with adequate Portland cement that effectively isolates the subsurface. The chief threat for such wells is mechanical disruption of the cement, cement/steel, or cement/caprock interfaces. This can occur through wellbore operations that pressurize/depressurize the steel tubing or create temperature transients (e.g., injection, production, hydraulic fracturing, and mechanical testing) as well as reservoir-scale stresses (e.g., filling or depletion of the reservoir) and tectonic stresses (e.g., the mobility of salt). However, there is relatively limited information available on the hydrologic consequences of such processes. Toward this end, we discuss recent experiments and computational models of coupled geomechanical and hydrologic processes in wellbore systems. Triaxial coreflood experiments with tomography were conducted on synthetic wellbore systems including cement-steel, rock-cement and rock-cement-steel composites. The aim of the experiments was to induce stresses through application of axial loads in order to create defects within the cement or at the cement/steel or cement/rock interface. High injection fluid pressures (supercritical CO2 × brine) were applied to the base of the initially impermeable composites. Mechanical failure resulted in creation of permeability, which was measured as a function of time (allowing for the possibility of Portland cement to deform and modify permeability). In addition, fracture patterns were characterized using x-ray tomography. We used the computer code FEHM to study coupled hydrologic and mechanical processes in the near-wellbore environment. The wellbore model was developed as a wedge within a radially symmetric 3D volume. The grid elements consist of the steel casing, the casing-cement interface, the

  12. Double diameter boring tool

    Science.gov (United States)

    Ashbaugh, Fred N.; Murry, Kenneth R.

    1988-12-27

    A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

  13. A 3-D wellbore simulator (WELLTHER-SIM) to determine the thermal diffusivity of rock-formations

    Science.gov (United States)

    Wong-Loya, J. A.; Santoyo, E.; Andaverde, J.

    2017-06-01

    Acquiring thermophysical properties of rock-formations in geothermal systems is an essential task required for the well drilling and completion. Wellbore thermal simulators require such properties for predicting the thermal behavior of a wellbore and the formation under drilling and shut-in conditions. The estimation of static formation temperatures also needs the use of these properties for the wellbore and formation materials (drilling fluids and pipes, cements, casings, and rocks). A numerical simulator (WELLTHER-SIM) has been developed for modeling the drilling fluid circulation and shut-in processes of geothermal wellbores, and for the in-situ determination of thermal diffusivities of rocks. Bottomhole temperatures logged under shut-in conditions (BHTm), and thermophysical and transport properties of drilling fluids were used as main input data. To model the thermal disturbance and recovery processes in the wellbore and rock-formation, initial drilling fluid and static formation temperatures were used as initial and boundary conditions. WELLTHER-SIM uses these temperatures together with an initial thermal diffusivity for the rock-formation to solve the governing equations of the heat transfer model. WELLTHER-SIM was programmed using the finite volume technique to solve the heat conduction equations under 3-D and transient conditions. Thermal diffusivities of rock-formations were inversely computed by using an iterative and efficient numerical simulation, where simulated thermal recovery data sets (BHTs) were statistically compared with those temperature measurements (BHTm) logged in some geothermal wellbores. The simulator was validated using a well-documented case reported in the literature, where the thermophysical properties of the rock-formation are known with accuracy. The new numerical simulator has been successfully applied to two wellbores drilled in geothermal fields of Japan and Mexico. Details of the physical conceptual model, the numerical

  14. Reduced-Order Model for Leakage Through an Open Wellbore from the Reservoir due to Carbon Dioxide Injection

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Lehua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Oldenburg, Curtis M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-07-26

    Potential CO2 leakage through existing open wellbores is one of the most significant hazards that need to be addressed in geologic carbon sequestration (GCS) projects. In the framework of the National Risk Assessment Partnership (NRAP) which requires fast computations for uncertainty analysis, rigorous simulation of the coupled wellbore-reservoir system is not practical. We have developed a 7,200-point look-up table reduced-order model (ROM) for estimating the potential leakage rate up open wellbores in response to CO2 injection nearby. The ROM is based on coupled simulations using T2Well/ECO2H which was run repeatedly for representative conditions relevant to NRAP to create a look-up table response-surface ROM. The ROM applies to a wellbore that fully penetrates a 20-m thick reservoir that is used for CO2 storage. The radially symmetric reservoir is assumed to have initially uniform pressure, temperature, gas saturation, and brine salinity, and it is assumed these conditions are held constant at the far-field boundary (100 m away from the wellbore). In such a system, the leakage can quickly reach quasi-steady state. The ROM table can be used to estimate both the free-phase CO2 and brine leakage rates through an open well as a function of wellbore and reservoir conditions. Results show that injection-induced pressure and reservoir gas saturation play important roles in controlling leakage. Caution must be used in the application of this ROM because well leakage is formally transient and the ROM lookup table was populated using quasi-steady simulation output after 1000 time steps which may correspond to different physical times for the various parameter combinations of the coupled wellbore-reservoir system.

  15. Mafic replenishment of multiple felsic reservoirs at the Mono domes and Mono Lake islands, California

    Science.gov (United States)

    Bray, Brandon; Stix, John; Cousens, Brian

    2017-07-01

    The Mono Basin has been the site of frequent volcanic activity over the past 60,000 years, including the emplacement of the Mono domes and Mono Lake islands. The Mono Basin lavas are the youngest and most poorly understood products of the Long Valley Volcanic Field. We have undertaken a study of Mono Basin volcanism encompassing whole-rock major and trace element, Sr, Nd, Pb, and O isotopic, and electron microprobe glass, plagioclase, and amphibole analyses. Variations in major and trace elements suggest that fractional crystallization of feldspar (Sr, K2O), apatite (P2O5), titanomagnetite (V), zircon (Zr), and allanite (La, Ce) has influenced the evolution of the Mono Basin lavas. Field observations, petrography, and chemistry together demonstrate that injection of more mafic magma is a common process throughout the Mono Basin. Mafic enclaves of the Mono domes are stretched and rounded, with chilled margins between enclave and host rhyolite. Thin sections reveal millimeter-scale inclusions of rhyolite in the enclaves and vice versa along the host-enclave border. Paoha Island dacite has glass with 67-72 wt% SiO2 and contains microscopic clots of more mafic glasses, with SiO2 contents as low as 64 wt%. Isotopically, the June Lake and Black Point basalts and the Mono dome enclaves represent the least evolved material in the Long Valley Volcanic Field, with 87Sr/86Sri 0.5126. The silicic Mono Lake lavas and Mono dome rhyolites display a significant crustal component, with 87Sr/86Sri >0.7058 and 143Nd/144Nd 19 and δ18O >+6.5‰. The Mono Lake lavas generally are younger and less evolved than the Mono domes, with enrichment in trace elements including Ba and Sr accompanied by lower 143Nd/144Nd and higher 206Pb/204Pb. This implies that the Mono domes and the Mono Lake lavas are derived from different magma batches, if not from separate magma chambers. There is no systematic relationship between the degree of chemical evolution and the lava ages, indicating that several

  16. Shale-Gas Experience as an Analog for Potential Wellbore Integrity Issues in CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Carey, James W. [Los Alamos National Laboratory; Simpson, Wendy S. [Los Alamos National Laboratory; Ziock, Hans-Joachim [Los Alamos National Laboratory

    2011-01-01

    Shale-gas development in Pennsylvania since 2003 has resulted in about 19 documented cases of methane migration from the deep subsurface (7,0000) to drinking water aquifers, soils, domestic water wells, and buildings, including one explosion. In all documented cases, the methane leakage was due to inadequate wellbore integrity, possibly aggravated by hydrofracking. The leakage of methane is instructive on the potential for CO{sub 2} leakage from sequestration operations. Although there are important differences between the two systems, both involve migrating, buoyant gas with wells being a primary leakage pathway. The shale-gas experience demonstrates that gas migration from faulty wells can be rapid and can have significant impacts on water quality and human health and safety. Approximately 1.4% of the 2,200 wells drilled into Pennsylvania's Marcellus Formation for shale gas have been implicated in methane leakage. These have resulted in damage to over 30 domestic water supplies and have required significant remediation via well repair and homeowner compensation. The majority of the wellbore integrity problems are a result of over-pressurization of the wells, meaning that high-pressure gas has migrated into an improperly protected wellbore annulus. The pressurized gas leaks from the wellbore into the shallow subsurface, contaminating drinking water or entering structures. The effects are localized to a few thousands of feet to perhaps two-three miles. The degree of mixing between the drinking water and methane is sufficient that significant chemical impacts are created in terms of elevated Fe and Mn and the formation of black precipitates (metal sulfides) as well as effervescing in tap water. Thus it appears likely that leaking CO{sub 2} could also result in deteriorated water quality by a similar mixing process. The problems in Pennsylvania highlight the critical importance of obtaining background data on water quality as well as on problems associated with

  17. Chemical and Physical Reactions of Wellbore Cement under CO2 Storage Conditions: Effects of Cement Additives

    Science.gov (United States)

    Kutchko, B. G.; Strazisar, B. R.; Huerta, N.; Lowry, G. V.; Dzombak, D. A.; Thaulow, N.

    2008-12-01

    Sequestration of CO2 into geologic formations requires long-term storage and low leakage rates to be effective. Active and abandoned wells in candidate storage formations must be evaluated as potential leakage points. Wellbore integrity is an important part of an overall integrated assessment program being developed at NETL to assess potential risks at CO2 storage sites. Such a program is needed for ongoing policy and regulatory decisions for geologic carbon sequestration. The permeability and integrity of the cement in the well is a primary factor affecting its ability to prevent leakage. Cement must be able to maintain low permeability over lengthy exposure to reservoir conditions in a CO2 injection and storage scenario. Although it is known that cement may be altered by exposure to CO2, the results of ongoing research indicate that cement curing conditions, fluid properties, and cement additives play a significant role in the rate of alteration and reaction. The objective of this study is to improve understanding of the factors affecting wellbore cement integrity for large-scale geologic carbon sequestration projects. Due to the high frequency use of additives (pozzolan) in wellbore cement, it is also essential to understand the reaction of these cement-pozzolan systems upon exposure to CO2 under sequestration conditions (15.5 MPa and 50°C). Laboratory experiments were performed to determine the physical and chemical changes, as well as the rate of alteration of commonly used pozzolan-cement systems under simulated sequestration reservoir conditions, including both supercritical CO2 and CO2-saturated brine. The rate of alteration of the cement-pozzolan systems is considerably faster than with neat cement. However, the alteration of physical properties is much less significant with the pozzolanic blends. Permeability of a carbonated pozzolanic cement paste remains sufficiently small to block significant vertical migration of CO2 in a wellbore. All of the

  18. Final Scientific/Technical Report for "Nanite" for Better Well-Bore Integrity and Zonal Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Veedu, Vinod [Oceanit Laboratories, Inc., Honolulu, HI (United States); Hadmack, Michael [Oceanit Laboratories, Inc., Honolulu, HI (United States); Pollock, Jacob [Oceanit Laboratories, Inc., Honolulu, HI (United States); Pernambuco-Wise, Paul [Oceanit Laboratories, Inc., Honolulu, HI (United States); Ah Yo, Derek [Oceanit Laboratories, Inc., Honolulu, HI (United States)

    2017-05-30

    Nanite™ is a cementitious material that contains a proprietary formulation of functionalized nanomaterial additive to transform conventional cement into a smart material responsive to pressure (or stress), temperature, and any intrinsic changes in composition. This project has identified optimal sensing modalities of smart well cement and demonstrated how real-time sensing of Nanite™ can improve long-term wellbore integrity and zonal isolation in shale gas and applicable oil and gas operations. Oceanit has explored Nanite’s electrical sensing properties in depth and has advanced the technology from laboratory proof-of-concept to sub-scale testing in preparation for field trials.

  19. Modeling Methane Leakage from Faulty Wellbores in the Denver-Julesburg Basin, Colorado

    Science.gov (United States)

    Lackey, G.; Rajaram, H.; Karra, S.; Sherwood, O.; Burke, T. L.

    2015-12-01

    Regulations in the state of Colorado mandate that all oil and gas wells be constructed with surface casings that extend 50 feet below the depth of the deepest potable aquifer, and production casings that are cemented to at least 200 feet above the shallowest producing formation. Building wells in accordance with the minimum regulations leaves an uncemented annulus between the production casing and the surrounding rock matrix, extending from the bottom of the surface casing to the top of the production casing cement. In Colorado, this annulus is sealed at the ground surface by the "bradenhead valve". Stray methane can enter the uncemented annulus through faulty cement in the producing formation or an intermediate gas-bearing zone and migrate upwards along the production casing. The gas dissolves into the annular fluid and accumulates below the bradenhead valve building pressure. Data from the Colorado Oil and Gas Conservation Commission (COGCC) indicates that 1,492 wells in the Denver-Julesburg (DJ) Basin have recorded bradenhead pressures greater than 20 psi since 2007. A leak of this kind creates the potential for both the single-phase transport of dissolved methane and the multiphase transport of methane gas away from the well. The degree to which methane transport occurs depends not only on the size of the leak but also the construction of the wellbore. In Colorado, the definition of potable groundwater has changed with time. To meet increasing demands for water, drinking water wells have been drilled deeper. As a result, there are potentially 4,144 wells in the DJ Basin with surface casings too shallow to protect the deepest potable aquifer. In this work, we investigate how a methane leak into the open annulus of an oil and gas wellbore, could result in the transport of dissolved and gas phase methane into a nearby drinking water aquifer. We construct a multiphase wellbore model that computes the pressure distribution and gas fraction along the uncemented

  20. Final Research Performance Progress Report: Geothermal Resource Development with Zero Mass Withdrawal, Engineered Convection, and Wellbore Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Richard [Louisiana State Univ., Baton Rouge, LA (United States); Tyagi, Mayank [Louisiana State Univ., Baton Rouge, LA (United States); Radonjic, Mileva [Louisiana State Univ., Baton Rouge, LA (United States); Dahi, Arash [Louisiana State Univ., Baton Rouge, LA (United States); Wang, Fahui [Louisiana State Univ., Baton Rouge, LA (United States); John, Chacko [Louisiana State Univ., Baton Rouge, LA (United States); Kaiser, Mark [Louisiana State Univ., Baton Rouge, LA (United States); Snyder, Brian [Louisiana State Univ., Baton Rouge, LA (United States); Sears, Stephen [Louisiana State Univ., Baton Rouge, LA (United States)

    2017-07-07

    This project is intended to demonstrate the technical and economic feasibility, and environmental and social attractiveness of a novel method of heat extraction from geothermal reservoirs. The emphasis is on assessing the potential for a heat extraction method that couples forced and free convection to maximize extraction efficiency. The heat extraction concept is enhanced by considering wellbore energy conversion, which may include only a boiler for a working fluid, or perhaps a complete boiler, turbine, and condenser cycle within the wellbore. The feasibility of this system depends on maintaining mechanical and hydraulic integrity of the wellbore, so the material properties of the casing-cement system are examined both experimentally and with well design calculations. The attractiveness depends on mitigation of seismic and subsidence risks, economic performance, environmental impact, and social impact – all of which are assessed as components of this study.

  1. A multibody dynamics model of contact between the drillstring and the wellbore and the rock penetration process

    Directory of Open Access Journals (Sweden)

    Ningyu Wang

    2015-05-01

    Full Text Available This article models the contact between the drillstring with large slenderness ratio and the extending rigid wellbore based on the multibody dynamics method. The drillstring is modeled as absolute nodal coordinate formulation beams with contact detection points. An algorithm is developed to locate the contact points and calculate the contact forces when the drillstring is sliding and rotating in the wellbore. This provides support force and friction for the moving drillstring and effectively confines it inside the wellbore. A rock penetration model is established based on the rock-breaking velocity equation. The governing equation for the full-hole drilling system including the drillstring and the contact model is established and solved. A rock penetration correction method is proposed to stabilize the computation and to model and simulate the slide drilling process. A field drilling process is modeled and simulated. The simulation result fits the experimental result well.

  2. Small diameter carbon nanopipettes

    Science.gov (United States)

    Singhal, Riju; Bhattacharyya, Sayan; Orynbayeva, Zulfiya; Vitol, Elina; Friedman, Gary; Gogotsi, Yury

    2010-01-01

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 °C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 °C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  3. Explaining Spatial Variability in Wellbore Impairment Risk for Pennsylvania Oil and Gas Wells, 2000-2014

    Science.gov (United States)

    Santoro, R.; Ingraffea, A. R.

    2015-12-01

    Previous modeling (ingraffea et al. PNAS, 2014) indicated roughly two-times higher cumulative risk for wellbore impairment in unconventional wells, relative to conventional wells, and large spatial variation in risk for oil and gas wells drilled in the state of Pennsylvania. Impairment risk for wells in the northeast portion of the state were found to be 8.5-times greater than that of wells drilled in the rest of the state. Here, we set out to explain this apparent regional variability through Boosted Regression Tree (BRT) analysis of geographic, developmental, and general well attributes. We find that regional variability is largely driven by the nature of the development, i.e. whether conventional or unconventional development is dominant. Oil and natural gas market prices and total well depths present as major influences in wellbore impairment, with moderate influences from well densities and geologic factors. The figure depicts influence paths for predictors of impairments for the state (top left), SW region (top right), unconventional/NE region (bottom left) and conventional/NW region (bottom right) models. Influences are scaled to reflect percent contributions in explaining variability in the model.

  4. The Mechanism of Wellbore Weakening in Worn Casing-Cement-Formation System

    Directory of Open Access Journals (Sweden)

    Zheng Shen

    2014-01-01

    Full Text Available Maintaining casing integrity, in terms of downhole zonal isolations and well stability, is extremely important in oil/gas wells. Casing wear occurs not only in directional drilling, but also in vertical drilling with a slight deviation angle. In most hydrocarbon wells, deteriorated casing was reported from the onset of casing wear by the presence of friction force during the rotation of drillpipe. The friction force against the casing wall causes the reduction of casing strength. Furthermore, the rotation of drillpipe combined with corrosive drilling fluids could dramatically degrade the casing strength. We used a finite element analysis to focus on the stress evolution in worn casings. Comparison study between worn casing and perfect casing was conducted. Our study showed that the thermal load significantly increases the stress concentration of the worn casing in the wellbore. Finite element solutions indicated that the radial stress of the worn casing is not affected as much as the hoop stress. Along with the increased burst pressure or the elevated temperature, the unworn portion of the casing also suffers from severe compression stress. This work is important to broadening the understanding of well engineers through addressing the true stress profile of worn casing in cemented wellbore.

  5. Impacts of shaking Bengkulus seismicity to subsurface Wellbore in the XX area

    Science.gov (United States)

    Rusli, Saifatur; Pratama, M. Ardian; Mardiyan, Hilman; Mirza, Finisha, Brian

    2016-05-01

    Bengkulu earthquake was happened on Wednesday, May 5th 2010 at 23:29:03 WIB (UTC-7) with magnitude 6.5 Richter scale. The Epicentrum was very close to Mentawai Fault System located on latitude 4.063°S and longitude 101.085°E with depth subsurface 27 kms. It was occurred the result of the Indian Ocean Plate-Australia's activity with low angled-subducted beneath the island of Sumatra. Shaking Bengkulus seismicity impacted subsurface in the XX Area which situated on South Palembang Sub-Basin part of South Sumatra Basin (SSB) about 200 kms far away from the epicentrum. Due to XX Area has some producing wells so that the seismicity activities as hypothetically impacts to Subsurface Wellbore which has caused some wells casing problems in the same depth. The wells casing problem shown after conducted routine sand bailer by Sand Line Unit, it was a downhole device used to remove debris sands or similar small particles around the fishingnecks of downhole tools or equipment in the wellbore, and then Sand Bailer tools got scratch at one side body. Similarly, Sand Bailer tools couldnt lowered until Total Depth and got samples sands slightly. At the end, it has impacted to well performance to produce oil in the XX Area.

  6. Incorporating electrokinetic effects in the porochemoelastic inclined wellbore formulation and solution.

    Science.gov (United States)

    Nguyen, Vinh X; Abousleiman, Youname N

    2010-03-01

    The porochemoelectroelastic analytical models and solutions have been used to describe the response of chemically active and electrically charged saturated porous media such as clays, shales, and biological tissues. However, these attempts have been restricted to one-dimensional consolidation problems, which are very limited in practice and not general enough to serve as benchmark solutions for numerical validation. This work summarizes the general linear porochemoelectroelastic formulation and presents the solution of an inclined wellbore drilled in a fluid-saturated chemically active and ionized formation, such as shale, and subjected to a three-dimensional in-situ state of stress. The analytical solution to this geometry incorporates the coupled solid deformation and simultaneous fluid/ion flows induced by the combined influences of pore pressure, chemical potential, and electrical potential gradients under isothermal conditions. The formation pore fluid is modeled as an electrolyte solution comprised of a solvent and one type of dissolved cation and anion. The analytical approach also integrates into the solution the quantitative use of the cation exchange capacity (CEC) commonly obtained from laboratory measurements on shale samples. The results for stresses and pore pressure distributions due to the coupled electrochemical effects are illustrated and plotted in the vicinity of the inclined wellbore and compared with the classical porochemoelastic and poroelastic solutions.

  7. Exploring the hole cleaning parameters of horizontal wellbore using two-phase Eulerian CFD approach

    Directory of Open Access Journals (Sweden)

    Satish K Dewangan

    2016-03-01

    Full Text Available The present investigation deals with the flow through concentric annulus with the inner cylinder in rotation. This work has got its importance in the petroleum industries in relation to the wellbore drilling. In wellbore drilling, the issue of the hole-cleaning is very serious problem especially in case of the horizontal drilling process. The effect of the various parameters like slurry flow velocity, inner cylinder rotational speed, inlet solid concentration which affect hole cleaning was discussed. Their effect on the pressure drop, wall shear stress, mixture turbulence kinetic energy, and solid-phase velocity and slip velocity were analyzed, which are responsible for solid-phase distribution. Flow was considered to be steady, incompressible and two-phase slurry flow with water as carrier fluid and silica sand as the secondary phase. Eulerian approach was used for modeling the slurry flow. Silica sand was considered of spherical shape with particle size of 180 µm. ANSYS FLUENT software was used for modeling and solution. Plotting was done using Tecplot software and Microsoft Office.

  8. Optimization of Integrated Reservoir, Wellbore, and Power Plant Models for Enhanced Geothermal Systems

    Science.gov (United States)

    Peluchette, Jason

    Geothermal energy has the potential to become a substantially greater contributor to the U.S. energy market. An adequate investment in Enhanced Geothermal Systems (EGS) technology will be necessary in order to realize the potential of geothermal energy. This study presents an optimization of a waterbased Enhanced Geothermal System (EGS) modeled for AltaRock Energy's Newberry EGS Demonstration location. The optimization successfully integrates all three components of the geothermal system: (1) the present wellbore design, (2) the reservoir design, and (3) the surface plant design. Since the Newberry EGS Demonstration will use an existing well (NWG 55-29), there is no optimization of the wellbore design, and the aim of the study for this component is to replicate the present wellbore conditions and design. An in-house wellbore model is used to accurately reflect the temperature and pressure changes that occur in the wellbore fluid and the surrounding casing, cement, and earth during injection and production. For the reservoir design, the existing conditions, such as temperature and pressure at depth and rock density, are incorporated into the model, and several design variables are investigated. The engineered reservoir is modeled using the reservoir simulator TOUGH2 while using the graphical interface PetraSim for visualization. Several fracture networks are investigated with the goal of determining which fracture network yields the greatest electrical output when optimized jointly with the surface plant. A topological optimization of the surface is completed to determine what type of power plant is best suited for this location, and a parametric optimization of the surface plant is completed to determine the optimal operating conditions. The conditions present at the Newberry, Oregon EGS project site are the basis for this optimization. The subsurface conditions are favorable for the production of electricity from geothermal energy with rock temperatures exceeding

  9. Resonant mono Higgs at the LHC

    CERN Document Server

    Basso, Lorenzo

    2015-01-01

    In recent years, the production of a SM particle with large missing transverse momentum, dubbed mono-X searches, have gained increasing attention. After the discovery of the Higgs boson in 2012, the run-II of the LHC will now scrutinise its properties, looking for BSM physics. In particular, one could search for mono-Higgs signals, that are typically studied in models addressing dark matter. However, this signal can appear also in models addressing the neutrino masses, if additional heavier neutrinos with masses at the electroweak scale are present. The latter will couple to the SM neutrinos and the Higgs boson, yielding a type of mono-Higgs signal not considered for dark matter: the resonant production of a Higgs boson and missing energy. In this paper, we address the LHC exclusion power of the latter with dedicated detector simulations, and reinterpret it in a benchmark model for neutrino mass generation.

  10. Lattice-Boltzmann simulations of low-Reynolds-number flow past mono- and bidisperse arrays of spheres

    NARCIS (Netherlands)

    Hoef, van der M.A.; Beetstra, R.; Kuipers, J.A.M.

    2005-01-01

    We report on lattice-Boltzmann simulations of slow fluid flow past mono- and bidisperse random arrays of spheres. We have measured the drag force on the spheres for a range of diameter ratios, mass fractions and packing fractions; in total, we studied 58 different parameter sets. Our simulation data

  11. Application of Neutron imaging in pore structure of hydrated wellbore cement: comparison of hydration of H20 with D2O based Portland cements

    Science.gov (United States)

    Dussenova, D.; Bilheux, H.; Radonjic, M.

    2012-12-01

    Wellbore Cement studies have been ongoing for decades. The studies vary from efforts to reduce permeability and resistance to corrosive environment to issues with gas migration also known as Sustained Casing Pressure (SCP). These practical issues often lead to health and safety problems as well as huge economic loss in oil and gas industry. Several techniques have been employed to reduce the impact of gas leakage. In this study we purely focus on expandable liners, which are introduced as part of oil well reconstruction and work-overs and as well abandonment procedures that help in prevention of SCP. Expandable liner is a tube that after application of a certain tool can increase its diameter. The increase in diameter creates extra force on hydrated cement that results in reducing width of interface fractures and cement-tube de-bonding. Moreover, this also causes cement to change its microstructure and other porous medium properties, primarily hydraulic conductivity. In order to examine changes before and after operations, cement pore structure must be well characterized and correlated to cement slurry design as well as chemical and physical environmental conditions. As modern oil well pipes and tubes contain iron, it is difficult to perform X-ray tomography of a bulk measurement of the cement in its wellbore conditions, which are tube wall-cement-tube wall. Neutron imaging is a complementary technique to x-ray imaging and is well suited for detection of light elements imbedded in metallic containers. Thus, Neutron Imaging (NI) is investigated as a tool for the detection of pore structure of hydrated wellbore cement. Recent measurements were conducted at the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) neutron imaging facility. NI is is highly sensitive to light elements such as Hydrogen (H). Oil well cements that have undergone a full hydration contain on average 30%-40% of free water in its pore structure. The unreacted water is the main

  12. Reaction and transport in wellbore interfaces under CO2 storage conditions: Experiments simulating debonded cement-casing interfaces

    NARCIS (Netherlands)

    Wolterbeek, T.K.T.; Peach, C.J.; Spiers, C.J.

    2013-01-01

    Debonding-defects at the interfaces between wellbore casing and cement are widely recognized as providing potential pathways for CO2 escape from geological storage systems. This study addresses how chemical reaction between CO2, cement and steel may affect the transport properties of such defects un

  13. Numerical simulation on streaming potentials in a wellbore; Koseinai no ryudo den`i ni kansuru suchi simulation

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, N. [Kyushu University, Fukuoka (Japan)

    1996-05-01

    This paper reports numerical computation of streaming potentials which are generated by transient pressure waves propagating the vicinity of wellbore wall immediately after a mud cake formed on the wellbore wall has been removed. One existing analysis solution on heat conduction was utilized upon changing the parameters in order to derive fluid pressure inside the ground bed. Calculations were carried out by using the existing three-dimensional finite difference method (partly re-written) based on the relationship constituted between the fluid pressure and the streaming potential. This paper presents results of calculating the streaming potentials in wellbores on models having wellbores filled with mud water in a cubic ground bed existing with ground bed water at saturation of 100%. The calculations have been conducted on the following cases: a case where permeability of the ground bed is small with the fluid under two conditions of low electric resistivity and high electric resistivity, a case where the permeability is large with the fluid under the above conditions, and a case where a small area of bore wall is covered with a rubber pad having high electric resistivity under a low electric resistivity condition. 8 refs., 5 figs.

  14. Adaptive forward-inverse modeling of reservoir fluids away from wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Ziagos, J P; Gelinas, R J; Doss, S K; Nelson, R G

    1999-07-30

    This Final Report contains the deliverables of the DeepLook Phase I project entitled, ''Adaptive Forward-Inverse Modeling of Reservoir Fluids Away from Wellbores''. The deliverables are: (i) a description of 2-D test problem results, analyses, and technical descriptions of the techniques used, (ii) a listing of program setup commands that construct and execute the codes for selected test problems (these commands are in mathematical terminology, which reinforces technical descriptions in the text), and (iii) an evaluation and recommendation regarding continuance of this project, including considerations of possible extensions to 3-D codes, additional technical scope, and budget for the out-years. The far-market objective in this project is to develop advanced technologies that can help locate and enhance the recovery of oil from heterogeneous rock formations. The specific technical objective in Phase I was to develop proof-of-concept of new forward and inverse (F-I) modeling techniques [Gelinas et al, 1998] that seek to enhance estimates (images) of formation permeability distributions and fluid motion away from wellbore volumes. This goes to the heart of improving industry's ability to jointly image reservoir permeability and flow predictions of trapped and recovered oil versus time. The estimation of formation permeability away from borehole measurements is an ''inverse'' problem. It is an inseparable part of modeling fluid flows throughout the reservoir in efforts to increase the efficiency of oil recovery at minimum cost. Classic issues of non-uniqueness, mathematical instability, noise effects, and inadequate numerical solution techniques have historically impeded progress in reservoir parameter estimations. Because information pertaining to fluid and rock properties is always sampled sparsely by wellbore measurements, a successful method for interpolating permeability and fluid data between the measurements must be

  15. Monetizing Leakage Risk of Geologic CO2 Storage using Wellbore Permeability Frequency Distributions

    Science.gov (United States)

    Bielicki, Jeffrey; Fitts, Jeffrey; Peters, Catherine; Wilson, Elizabeth

    2013-04-01

    Carbon dioxide (CO2) may be captured from large point sources (e.g., coal-fired power plants, oil refineries, cement manufacturers) and injected into deep sedimentary basins for storage, or sequestration, from the atmosphere. This technology—CO2 Capture and Storage (CCS)—may be a significant component of the portfolio of technologies deployed to mitigate climate change. But injected CO2, or the brine it displaces, may leak from the storage reservoir through a variety of natural and manmade pathways, including existing wells and wellbores. Such leakage will incur costs to a variety of stakeholders, which may affect the desirability of potential CO2 injection locations as well as the feasibility of the CCS approach writ large. Consequently, analyzing and monetizing leakage risk is necessary to develop CCS as a viable technological option to mitigate climate change. Risk is the product of the probability of an outcome and the impact of that outcome. Assessment of leakage risk from geologic CO2 storage reservoirs requires an analysis of the probabilities and magnitudes of leakage, identification of the outcomes that may result from leakage, and an assessment of the expected economic costs of those outcomes. One critical uncertainty regarding the rate and magnitude of leakage is determined by the leakiness of the well leakage pathway. This leakiness is characterized by a leakage permeability for the pathway, and recent work has sought to determine frequency distributions for the leakage permeabilities of wells and wellbores. We conduct a probabilistic analysis of leakage and monetized leakage risk for CO2 injection locations in the Michigan Sedimentary Basin (USA) using empirically derived frequency distributions for wellbore leakage permeabilities. To conduct this probabilistic risk analysis, we apply the RISCS (Risk Interference of Subsurface CO2 Storage) model (Bielicki et al, 2013a, 2012b) to injection into the Mt. Simon Sandstone. RISCS monetizes leakage risk

  16. Permeability Changes on Wellbore Cement Fractures Modified by Geochemical and Geomechanical Processes

    Science.gov (United States)

    Rod, K. A.; Um, W.

    2015-12-01

    Experimental studies were conducted using batch reactors, X-ray microtomography (XMT), and computational fluid dynamics (CFD) modeling to determine changes in cement fracture surfaces, fluid flow pathways and permeability, and cement fracture propagation with geochemical and geomechanical processes. Portland cement-basalt interface sample with artificial fractures was prepared to study the geochemical and geomechanical effects on the integrity of wellbores containing defects caused by subsurface activities. Cement-basalt interface sample was subjected to mechanical stress at 2.7 MPa before the chemical reaction. CFD modeling was performed to simulate flow of supercritical CO2 within the fractures before and after the application of mechanical stress. The model results highlighted the complex flow characteristics within the fracture and also changes in flow patterns due to application of geomechanical stress. The CFD model predicted ~45% increase in permeability after the application of geomechanical force, which increases the fracture aperture. The same sample was reacted with CO2-saturated groundwater with impurity H2S (1 wt.%) at 50°C and 10 MPa for 3 to 3.5 months under static conditions. XMT provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Even after a 3.5-month reaction with CO2-H2S-saturated groundwater at 50°C and 10 MPa, CaCO3 (s) precipitation occurred more extensively within the cement fracture rather than along the cement-basalt interfaces. Micro X-ray diffraction analysis also showed that major cement carbonation products of CO2-saturated groundwater reacting with impurity H2S were calcite, aragonite, and vaterite, consistent with cement carbonation by pure CO2-saturated groundwater, while pyrite was not identified due to low H2S content. The experimental results imply that the wellbore cement with fractures is likely to be healed during exposure to CO2-saturated

  17. Hydro-mechanical simulations of well abandonment at the Ketzin pilot site for CO2 storage verify wellbore system integrity

    Science.gov (United States)

    Unger, Victoria; Kempka, Thomas

    2015-04-01

    In geological underground utilisation, operating and abandoned wells have been identified as a main potential leakage pathways for reservoir fluids. In the scope of the well abandonment procedure currently carried out at the Ketzin pilot site for CO2 storage in Germany, a hydro-mechanical model was built to carry out a coupled analysis of the integrity in the entire wellbore system. The main aim of the present study was to assess the impacts of stress changes associated with CO2 injection as well as the cement backfill undertaken in the scope of well abandonment. A numerical model comprising cement sheaths, steel casings, tubing, multiple packers and wellbore annuli was implemented to enable a detailed representation of the entire wellbore system. The numerical model grid has a horizontal discretisation of 5 m x 5 m to focus on near wellbore effects, whereby element sizes increase with increasing distance from the wellbore. Vertical grid discretisation uses a tartan grid type over the entire model thickness of 1,500 m to ensure a sufficient discretisation of all wellbore system elements as well as of the reservoir unit. The total number of elements amounts to 210,672. Mechanical model parameters were taken from geological, drilling, logging and laboratory test data based on Ketzin pilot site-specific information as well as related literature (Kempka et al., 2014). The coupled calculations were performed using an elasto-plastic constitutive law, whereby an initial simulation run ensured a static mechanical equilibrium to represent the initial state before the start of CO2 injection. Thereto, gravitational load of the overburden rocks and pore pressure distribution following available well logs were integrated for initial model parameterisation including a normal faulting stress regime defined by a horizontal to vertical total stress ratio of 0.85. A correction accounting for the temperature and pressure dependent CO2 density was carried out in advance of each

  18. Search for Exotic mono-jet and mono-photon signatures with the ATLAS detector

    Directory of Open Access Journals (Sweden)

    Rezvani Reyhaneh

    2013-05-01

    Full Text Available Mono-jet and mono-photon signatures are final states in a variety of scenarios beyond the Standard Model, such as the Large Extra Dimension models, gauge-mediated SUSY breaking scenarios, and models with pair production of Weakly Interacting Massive Particles considered as dark matter candidates. The produced exotic particles do not interact with the detector, resulting in missing transverse energy. The results of searches, performed in the ATLAS experiment at the LHC, for new physics in final states with an energetic jet or photon and large missing transverse energy are presented. The mono-jet search is performed using both 4.6 fb−1 of 7 TeV and 10.5 fb−1 of 8 TeV data, while the mono-photon results correspond to 4.6 fb−1 of 7 TeV data.

  19. Open hole packer for high pressure service in a five hundred degree fahrenheit precambrian wellbore

    Energy Technology Data Exchange (ETDEWEB)

    Dreesen, D.S.; Miller, J.R.; Halbardier, F.A.; Nicholson, R.W.

    1985-01-01

    Massive hydraulic fracturing (MHF) from a lower wellbore (EE-2) created a large man-made reservoir which did not intersect the upper well (EE-3). To create a heat extraction flow loop, the upper well was sidetracked and redrilled (EE-3A) down into a microseismic cloud around EE-2 mapped during the MHF. The potential to intersect numerous fracture zones in the redrilled bore was apparent from seismicity. To economically and effectively isolate and test these microseismic zones required that a functional open hole packer be developed. The packer would be exposed to soak temperatures as high as 500/sup 0/F (260/sup 0/C) with cool down to 100/sup 0/F (40/sup 0/C) at differential pressures exceeding 5000 psi (35 Mpa). A functional packer has been designed, manufactured, and successfully used for the creation of a hot dry rock (HDR) reservoir. 5 figs., 1 tab.

  20. Systematic assessment of wellbore integrity for geologic carbon storage projects using regulatory and industry information

    Energy Technology Data Exchange (ETDEWEB)

    Moody, Mark [Battelle Memorial Institute, Columbus, OH (United States); Sminchak, J.R. [Battelle Memorial Institute, Columbus, OH (United States)

    2015-11-01

    Under this three year project, the condition of legacy oil and gas wells in the Midwest United States was evaluated through analysis of well records, well plugging information, CBL evaluation, sustained casing pressure (SCP) field testing, and analysis of hypothetical CO2 test areas to provide a realistic description of wellbore integrity factors. The research included a state-wide review of oil and gas well records for Ohio and Michigan, along with more detailed testing of wells in Ohio. Results concluded that oil and gas wells are clustered along fields in areas. Well records vary in quality, and there may be wells that have not been identified in records, but there are options for surveying unknown wells. Many of the deep saline formations being considered for CO2 storage have few wells that penetrate the storage zone or confining layers. Research suggests that a variety of well construction and plugging approaches have been used over time in the region. The project concluded that wellbore integrity is an important issue for CO2 storage applications in the Midwest United States. Realistic CO2 storage projects may cover an area in the subsurface with several hundred legacy oil and gas wells. However, closer inspection may often establish that most of the wells do not penetrate the confining layers or storage zone. Therefore, addressing well integrity may be manageable. Field monitoring of SCP also indicated that tested wells provided zonal isolation of the reservoirs they were designed to isolate. Most of these wells appeared to exhibit gas pressure originating from intermediate zones. Based on these results, more flexibility in terms of cementing wells to surface, allowing well testing, and monitoring wells may aid operators in completing CO2 storage project. Several useful products were developed under this project for examining wellbore integrity for CO2 storage applications including, a

  1. Development of a thermal resistance model to evaluate wellbore heat exchange efficiency

    Directory of Open Access Journals (Sweden)

    Albert A. Koenig, Martin F. Helmke

    2014-01-01

    Full Text Available A new model is proposed to simulate conduction of heat between a pipe loop in a geoexchange system and the ground. The approach employs the thermal resistor technique coupled with a conduction shape factor modified by an occultation factor. The model is compared to available data and demonstrates suitable agreement with previous studies. The model facilitates a parametric study of borehole resistance as a function of geometry and thermal conductivity of the components. By spacing the legs of the loop against the borehole and increasing the pipe size, the study shows that one can maximize the wellbore heat transfer using a moderate (1.2 W/mK thermal conductivity grout. This study further demonstrates that improved well construction techniques could increase the efficiency of most closed-loop geothermal systems by 10 percent.

  2. A systematic approach for wellbore drilling and placement of SAGD well pairs and infill wells

    Energy Technology Data Exchange (ETDEWEB)

    Illfelder, H.; Forbes, E.; McElhinney, G.; Rennie, A. [PathFinder, A Schlumberger Company (Canada); Schaepsmeyer, H.; Krawchuk, A. [Cenovus Energy Incorporated (Canada)

    2011-07-01

    In Alberta, Canada, steam assisted gravity drainage (SAGD) is used to enhance oil recovery in heavy oil reservoirs. This process requires the drilling of producer and injector wells which is usually done using standard techniques. These techniques lead to sub-optimal well-placement and thus this paper aims to define a systematic approach for the drilling process. Several methods to improve the drilling process are demonstrated including careful control of the directional drilling process, borehole tortuosity minimization and producer and injector wellbore placement. The paper also presents the real-time analysis of the drilling and advanced ranging (RADAR) system, a service brand and platform developed for implementing the improved methods while drilling is in progress. This paper develops a systematic approach to placing SAGD wells in an improved manner and presents the RADAR system which allows the application of these methods.

  3. Third-order elastic solution of the stress field around a wellbore

    Energy Technology Data Exchange (ETDEWEB)

    Elata, D.

    1996-04-01

    Within a certain range of strain, consolidated granular materials may be characterized as nonlinear elastic solids. The nonlinearity can be easily observed by examining the effect of stress on the acoustical properties of the material. Ignoring damage evolution and failure that occur in higher strains and the hysteretic behavior due to intercyranular friction, the material can be modeled as a nonlinear hyperelastic solid. A simple example of such a model is formulating the strain energy as a third-order polynomial of the strain invariants. This model is limited in the sense that the material is assumed to be isotropic with respect to the stress free state, and that the mechanical response of the material is described by only five material constants. Nevertheless, this model is appealing because it naturally exhibits stress dependent stiffness and stress induced anisotropy, and it allows a different mechanical response to positive and negative volume changes. In this work, this model is used to calculate the stress field around a wellbore. Many well logging tools use acoustics (e.g., tube, surface, torsion, and flexural waves) to detect pore fluids and ore in the surrounding granular rock. By modeling the rock as an isotropic third-order elastic material the effects of the inhomogeneous stiffness and the stress induced anisotropy may be examined. Analysis of the tangential stress around a wellbore in an isotropic third-order elastic (TOE) material yields different results than the same analysis in the related isotropic linear elastic (LE) material (i.e., both materials have the same stiffness tensor at the stress free state). This difference modifies the far-field stress that is interpreted of from hydraulic fracturing data. The analysis in the present work is static and pore fluid effects are ignored.

  4. 21 CFR 172.834 - Ethoxylated mono- and diglycerides.

    Science.gov (United States)

    2010-04-01

    ... ethoxylated mono-and diglycerides (polyoxyethylene (20) mono- and diglycerides of fatty acids) (polyglycerate... labeling it shall be followed by either “polyoxyethylene (20) mono-and diglycerides of fatty acids” or... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD...

  5. A cleaner cut : oilfield service firm claims its rotary steerable cuts a cleaner wellbore at a faster clip than competitors

    Energy Technology Data Exchange (ETDEWEB)

    Mahony, J.

    2010-03-15

    Rotary steerable tools that use push-the-bit technology have a higher tendency to cut scored spiral wellbores than point-and-hit tools. This article described the Revolution rotary-steerable system (RSS) that was marketed in Canada by Houston-based Weatherford. The article outlined the benefits of the RSS including how it provides speed and a smoother wellbore to long-reach directional wells as well as an overall lower cost. Revolution RSS has drilled almost two million feet of wells worldwide and over one million feet onshore North America, primarily in the United States. Users of the Revolution RSS also claim that another advantage is its high rate-of-penetration. The Revolution RSS is available in 4 different bottomhole assembly sizes, ranging from 4 and three quarter inches to 6 and three quarter inches to the widest at 8 and three quarter inches. 1 ref., 1 fig.

  6. Thermal effects on fluid flow and hydraulic fracturing from wellbores and cavities in low-permeability formations

    Energy Technology Data Exchange (ETDEWEB)

    Yarlong Wang [Petro-Geotech Inc., Calgary, AB (Canada); Papamichos, Euripides [IKU Petroleum Research, Trondheim (Norway)

    1999-07-01

    The coupled heat-fluid-stress problem of circular wellbore or spherical cavity subjected to a constant temperature change and a constant fluid flow rate is considered. Transient analytical solutions for temperature, pore pressure and stress are developed by coupling conductive heat transfer with Darcy fluid flow in a poroelastic medium. They are applicable to lower permeability porous media suitable for liquid-waste disposal and also simulating reservoir for enhanced oil recovery, where conduction dominates the heat transfer process. A full range of solutions is presented showing separately the effects of temperature and fluid flow on pore pressure and stress development. It is shown that injection of warm fluid can be used to restrict fracture development around wellbores and cavities and generally to optimise a fluid injection operation. Both the limitations of the solutions and the convective flow effect are addressed. (Author)

  7. Comprehensive database of wellbore temperatures and drilling mud weight pressures by depth for Judge Digby field, Louisiana

    Science.gov (United States)

    Burke, Lauri

    2010-01-01

    This document serves as the repository for the unprocessed data used in the investigation of temperature and overpressure relations within the deep Tuscaloosa Formation in Judge Digby field. It is a compilation of all the publicly accessible wellbore temperature and pressure data for Judge Digby field, a prolific natural gas field producing from the Upper Cretaceous lower part of the Tuscaloosa Formation in the Gulf Coast region. This natural gas field is in Pointe Coupee Parish in the southern part of onshore Louisiana.

  8. Relative permeability of fractured wellbore cement: an experimental investigation using electrical resistivity monitoring for moisture content

    Science.gov (United States)

    Um, W.; Rod, K. A.; Strickland, C. E.

    2016-12-01

    Permeability is a critical parameter needed to understand flow in subsurface environments; it is particularly important in deep subsurface reservoirs where multiphase fluid flow is common, such as carbon sequestration and geothermal reservoirs. Cement is used in the annulus of wellbores due to its low permeable properties to seal aquifers, reducing leaks to adjacent strata. Extreme subsurface environments of CO2 storage and geothermal production conditions will eventually reduce the cement integrity, propagating fracture networks and increasing the permeability for air and/or water. To date, there have been no reproducible experimental investigations of relative permeability in fractured wellbore cement published. To address this gap, we conducted a series of experiments using fractured Portland cement monoliths with increasing fracture networks. The monolith cylinder sides were jacketed with heavy-duty moisture-seal heat-shrink tubing, then fractured using shear force applied via a hydraulic press. Fractures were generated with different severity for each of three monoliths. Stainless steel endcaps were fixed to the monoliths using the same shrink-wrapped jacket. Fracture characteristics were determined using X-ray microtomography and image analysis. Flow controllers were used to control flow of water and air to supply continuous water or water plus air, both of which were delivered through the influent end cap. Effluent air flow was monitored using a flow meter, and water flow was measured gravimetrically. To monitor the effective saturation of the fractures, a RCON2 concrete bulk electrical resistivity test device was attached across both endcaps and a 0.1M NaNO3 brine was used as the transport fluid to improve resistivity measurements. Water content correlated to resistivity measurements with a r2 > 0.96. Data from the experiments was evaluated using two relative permeability models, the Corey-curve, often used for modeling relative permeability in porous media

  9. A comprehensive mathematical model for estimating oil drainage rate in SAGD process considering wellbore/formation coupling effect

    Science.gov (United States)

    Cheng, Linsong; Gu, Hao; Huang, Shijun

    2016-11-01

    The aim of this work is to present a comprehensive mathematical model for estimating oil drainage rate in Steam-assisted gravity drainage (SAGD) process, more importantly, wellbore/formation coupling effect is considered. Firstly, mass and heat transfer in vertical and horizontal wellbores are described briefly. Then, a function of steam chamber height is introduced and the expressions for oil drainage rate in rising and expanding steam chamber stages are derived in detail. Next, a calculation flowchart is provided and an example is given to introduce how to use the proposed method. Finally, after the mathematical model is validated, the effects of wellhead steam injection rate on simulated results are further analyzed. The results indicate that heat injection power per meter reduces gradually along the horizontal wellbore, which affects both steam chamber height and oil drainage rate in the SAGD process. In addition, when production time is the same, the calculated oil drainage rate from the new method is lower than that from Butler's method. Moreover, the paper shows that when wellhead steam injection rate is low enough, the steam chamber is not formed at the horizontal well's toe position and enhancing the wellhead steam injection rate can increase the oil drainage rate.

  10. The Development of a Gas-Liquid Two-Phase Flow Sensor Applicable to CBM Wellbore Annulus.

    Science.gov (United States)

    Wu, Chuan; Wen, Guojun; Han, Lei; Wu, Xiaoming

    2016-11-18

    The measurement of wellbore annulus gas-liquid two-phase flow in CBM (coalbed methane) wells is of great significance for reasonably developing gas drainage and extraction processes, estimating CBM output, judging the operating conditions of CBM wells and analyzing stratum conditions. Hence, a specially designed sensor is urgently needed for real-time measurement of gas-liquid two-phase flow in CBM wellbore annulus. Existing flow sensors fail to meet the requirements of the operating conditions of CBM wellbore annulus due to such factors as an inapplicable measurement principle, larger size, poor sealability, high installation accuracy, and higher requirements for fluid media. Therefore, based on the principle of a target flowmeter, this paper designs a new two-phase flow sensor that can identify and automatically calibrate different flow patterns of two-phase flows. Upon the successful development of the new flow sensor, lab and field tests were carried out, and the results show that the newly designed sensor, with a measurement accuracy of ±2.5%, can adapt to the operating conditions of CBM wells and is reliable for long-term work.

  11. Implementation of Bounding Surface Model into ABAQUS and Its Application to Wellbore Stability Analysis

    Science.gov (United States)

    Chen, S.; Al-Muntasheri, G.; Abousleiman, Y. N.

    2014-12-01

    The critical state concept based bounding surface model is one of the most widely used elastoplastic constitutive models for geomaterials, attributed mainly to its essential feature of allowing plastic deformation to occur for stress points within the bounding surface and thus the capability to represent the realistic non-recoverable behaviour of soils and rocks observed under the cyclic loading. This paper develops an implicit integration algorithm for the bounding surface model, using the standard return mapping approach (elastic predictor-plastic corrector), to obtain the updated stresses for the given strain increments. The formulation of the constitutive integration requires the derivation of a supplementary differential equation to describe the evolution of a key variable, i.e., the ratio between the image stress and the current stress quantities. It is essentially an extension of the integration scheme presented in an earlier work used for the simple bounding surface version of modified Cam Clay associated with a substantially simplified hardening rule. The integration algorithm for the bounding surface model is implemented into the finite element analysis commercial program, ABAQUS, through the material interface of UMAT (user defined material subroutine), and then used for the analysis of wellbore stability problem. The predictions from the ABAQUS simulations are generally in excellent agreement with the available analytical solutions, thus demonstrating the accuracy and robustness of the proposed integration scheme.

  12. Calculations of Gas-liquid Equilibrium in Wellbore with High Carbon dioxide Flow

    Science.gov (United States)

    Zhang, Jiaming; Wu, Xiaodong; Wang, Bo; Liu, Kai; Gao, Yue

    2014-05-01

    Carbon dioxide injection not only enhances the oil recovery dramatically, but also it will reduce the greenhouse effect, therefore, Carbon dioxide injection technique is applied extensively. During the process of carbon dioxide displacement, when carbon dioxide breaks though into oil production wells, carbon dioxide content will impacts the phase state and physical properties of the mixed liquor in the wellbore, as a result, it will affect the calculation of temperature and pressure in oil production wells. Applying the conventional black-oil model to calculate the phase state of the miscible fluids is unacceptable. To tackle the problem, this paper uses the gas-liquid flash theory and component model to program software, so that the phase state (gas, liquid or gas-liquid) and physical properties of the mixed liquor (including hydrogen sulfide, carbon dioxide and hydrocarbon) under initial conditions is calculated, moreover, the impact of carbon dioxide content on the physical properties(mainly including density, viscosity, specific heat at const pressure, surface tension, etc) of mixed liquor in oil production wells is analyzed in this paper. The comparison of the results shows that this model can meet the engineering needs with high accuracy.

  13. Rapid computation of directional wellbore drawdown in a confined aquifer via Poisson resummation

    Science.gov (United States)

    Blumenthal, Benjamin J.; Zhan, Hongbin

    2016-08-01

    We have derived a rapidly computed analytical solution for drawdown caused by a partially or fully penetrating directional wellbore (vertical, horizontal, or slant) via Green's function method. The mathematical model assumes an anisotropic, homogeneous, confined, box-shaped aquifer. Any dimension of the box can have one of six possible boundary conditions: 1) both sides no-flux; 2) one side no-flux - one side constant-head; 3) both sides constant-head; 4) one side no-flux; 5) one side constant-head; 6) free boundary conditions. The solution has been optimized for rapid computation via Poisson Resummation, derivation of convergence rates, and numerical optimization of integration techniques. Upon application of the Poisson Resummation method, we were able to derive two sets of solutions with inverse convergence rates, namely an early-time rapidly convergent series (solution-A) and a late-time rapidly convergent series (solution-B). From this work we were able to link Green's function method (solution-B) back to image well theory (solution-A). We then derived an equation defining when the convergence rate between solution-A and solution-B is the same, which we termed the switch time. Utilizing the more rapidly convergent solution at the appropriate time, we obtained rapid convergence at all times. We have also shown that one may simplify each of the three infinite series for the three-dimensional solution to 11 terms and still maintain a maximum relative error of less than 10-14.

  14. Hydrocarbons Emissions Due to Wellbore and other Subsurface Leakage in the Uintah Basin, Utah

    Science.gov (United States)

    Watkins, C.; Lyman, S. N.

    2015-12-01

    The explosive growth of oil and gas production in the United States has focused public and regulatory attention on environmental impacts of hydrocarbon extraction, including air quality and climate impacts. One potentially important emissions source is subsurface leakage of natural gas. Better understanding of wellbore and other subsurface leaks are important in providing ways to decrease pollution while increasing the efficiency of oil and gas production. Soil gas measurements carried out by USGS over the last several years in Utah's oil and gas fields have shown that, while concentrations of methane in soils near wells are typically low, soil gas near some wells can contain more than 50% methane. In the summers of 2013-2015 we carried out campaigns to measure the emission rate of methane and other hydrocarbons from soils near wells in the Uintah Basin, Utah. We also measured emissions at several locations on individual well pads and determined that concentrations of hydrocarbons tend to decrease with distance from the well head. Soil emissions were also measured at non-well sites in the same area to determine background emission rates. Emissions from exposed coal, oil shale, gilsonite, and fault zone surfaces were also measured. Relationships of emissions with soil gas concentrations, meteorological conditions, and soil properties were also investigated.

  15. Montney unconventional gas : next generation, an integrated approach to optimizing wellbore completions technology

    Energy Technology Data Exchange (ETDEWEB)

    Tapper, N.; Schnell, R. [Talisman Energy Inc., Calgary, AB (Canada)

    2009-07-01

    The Montney Formation is a prolific tight gas reservoir located in the western Canadian Sedimentary Basin in British Columbia and Alberta. The key to achieving economic success in the Peace River Arch area lies with horizontal wells with multiple fractures. The driver for the next generation of completions involves using various area drilling and completion techniques as a starting point to lower the installation cost without affecting the completion or production results. This presentation discussed unconventional gas in the Montney Formation and a next generation, integrated approach to optimizing wellbore completions technology. In order to address the need to change from cemented liners with pump down plugs and perforations completions, the presentation provided background information on swellable packers that could take the place of cement. Swellpacker completion bottom hole assembly and design considerations were presented. A solution for reducing costs was presented along with 6 case histories. It was concluded that new technology is the key to reducing costs in the Montney. Technology must be thoroughly vetted by drilling and completion experts and properly applied. figs.

  16. On mono-W signatures in spin-1 simplified models

    Energy Technology Data Exchange (ETDEWEB)

    Haisch, Ulrich [Oxford Univ. (United Kingdom). Rudolf Peierls Centre for Theoretical Physics; CERN, Geneva (Switzerland). Theory Div.; Kahlhoefer, Felix [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Tait, Tim M.P. [California Univ., Irvine, CA (United States). Dept. of Physics and Astronomy

    2016-03-15

    The potential sensitivity to isospin-breaking effects makes LHC searches for mono-W signatures promising probes of the coupling structure between the Standard Model and dark matter. It has been shown, however, that the strong sensitivity of the mono-W channel to the relative magnitude and sign of the up-type and down-type quark couplings to dark matter is an artefact of unitarity violation. We provide three different solutions to this mono-W problem in the context of spin-1 simplified models and briefly discuss the impact that our findings have on the prospects of mono-W searches at future LHC runs.

  17. On mono-W signatures in spin-1 simplified models

    Directory of Open Access Journals (Sweden)

    Ulrich Haisch

    2016-09-01

    Full Text Available The potential sensitivity to isospin-breaking effects makes LHC searches for mono-W signatures promising probes of the coupling structure between the Standard Model and dark matter. It has been shown, however, that the strong sensitivity of the mono-W channel to the relative magnitude and sign of the up-type and down-type quark couplings to dark matter is an artifact of unitarity violation. We provide three different solutions to this mono-W problem in the context of spin-1 simplified models and briefly discuss the impact that our findings have on the prospects of mono-W searches at future LHC runs.

  18. Diameters of Triton and Pluto

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, D.; Cruikshank, D.P. (Hawaii Univ., Honolulu (USA). Inst. for Astronomy); Brown, R.H. (Hawaii Univ., Honolulu (USA). Dept. of Physics and Astronomy; Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics)

    1982-12-02

    Upper limits are reported to the thermal IR emission from Triton, the major satellite of Neptune, and Pluto, the outermost planet, that permit significant upper limits to be set on their diameters and also demonstrate that both are high albedo objects. These results exclude the possibility that Triton is the largest planetary satellite and are consistent with the small size of Pluto deduced from other data.

  19. Incorporating electrokinetic effects in the porochemoelastic inclined wellbore formulation and solution

    Directory of Open Access Journals (Sweden)

    Vinh X. Nguyen

    2010-03-01

    Full Text Available The porochemoelectroelastic analytical models and solutions have been used to describe the response of chemically active and electrically charged saturated porous media such as clays, shales, and biological tissues. However, these attempts have been restricted to one-dimensional consolidation problems, which are very limited in practice and not general enough to serve as benchmark solutions for numerical validation. This work summarizes the general linear porochemoelectroelastic formulation and presents the solution of an inclined wellbore drilled in a fluid-saturated chemically active and ionized formation, such as shale, and subjected to a three-dimensional in-situ state of stress. The analytical solution to this geometry incorporates the coupled solid deformation and simultaneous fluid/ion flows induced by the combined influences of pore pressure, chemical potential, and electrical potential gradients under isothermal conditions. The formation pore fluid is modeled as an electrolyte solution comprised of a solvent and one type of dissolved cation and anion. The analytical approach also integrates into the solution the quantitative use of the cation exchange capacity (CEC commonly obtained from laboratory measurements on shale samples. The results for stresses and pore pressure distributions due to the coupled electrochemical effects are illustrated and plotted in the vicinity of the inclined wellbore and compared with the classical porochemoelastic and poroelastic solutions.Modelos analíticos poroelásticos incluindo acoplamento químico e elétrico e soluções têm sido utilizados paradescrever a resposta de meios porosos saturados ativos química e eletricamente tais como argilas, folhelhos e tecidos biológicos. Entretanto tais tentativas têm sido restritas a problemas de consolidação unidimensional os quais exibem limitações na prática não constituindo exemplos realistas para validação de soluções numéricas. Este trabalho

  20. Numerical simulation in steam injection wellbores by mechanistic approach; Simulacao numerica do escoamento de vapor em pocos por uma abordagem mecanicista

    Energy Technology Data Exchange (ETDEWEB)

    Souza Junior, J.C. de; Campos, W.; Lopes, D.; Moura, L.S.S. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Thomas, A. Clecio F. [Universidade Estadual do Ceara (UECE), CE (Brazil)

    2008-07-01

    This work addresses to the development of a hydrodynamic and heat transfer mechanistic model for steam flow in injection wellbores. The problem of two-phase steam flow in wellbores has been solved recently by using available empirical correlations from petroleum industry (Lopes, 1986) and nuclear industry (Moura, 1991).The good performance achieved by mechanistic models developed by Ansari (1994), Hasan (1995), Gomez (2000) and Kaya (2001) supports the importance of the mechanistic approach for the steam flow problem in injection wellbores. In this study, the methodology to solve the problem consists in the application of a numerical method to the governing equations of steam flow and a marching algorithm to determine the distribution of the pressure and temperature along the wellbore. So, a computer code has been formulated to get numerical results, which provides a comparative study to the main models found in the literature. Finally, when compared to available field data, the mechanistic model for downward vertical steam flow in wellbores gave better results than the empirical correlations. (author)

  1. Computational studies of two-phase cement-CO2-brine interaction in wellbore environments

    Energy Technology Data Exchange (ETDEWEB)

    Carey, James William [Los Alamos National Laboratory; Lichtner, Peter C [Los Alamos National Laboratory

    2009-01-01

    Wellbore integrity is essential to ensuring long-term isolation of buoyant supercritical CO{sub 2} during geologic sequestration of CO{sub 2}. In this report, we summarize recent progress in numerical simulations of cement-brine-CO{sub 2} interactions with respect to migration of CO{sub 2} outside of casing. Using typical values for the hydrologic properties of cement, caprock (shale) and reservoir materials, we show that the capillary properties of good quality cement will prevent flow of CO{sub 2} into and through cement. Rather, CO{sub 2}, if present, is likely to be confined to the casing-cement or cement-formation interfaces. CO{sub 2} does react with the cement by diffusion from the interface into the cement, in which case it produces distinct carbonation fronts within the cement. This is consistent with observations of cement performance at the CO{sub 2}-enhanced oil recovery SACROC Unit in West Texas (Carey et al. 2007). For poor quality cement, flow through cement may occur and would produce a pattern of uniform carbonation without reaction fronts. We also consider an alternative explanation for cement carbonation reactions as due to CO{sub 2} derived from caprock. We show that carbonation reactions in cement are limited to surficial reactions when CO{sub 2} pressure is low (< 10 bars) as might be expected in many caprock environments. For the case of caprock overlying natural CO{sub 2} reservoirs for millions of years, we consider Scherer and Huet's (2009) hypothesis of diffusive steady-state between CO{sub 2} in the reservoir and in the caprock. We find that in this case, the aqueous CO{sub 2} concentration would differ little from the reservoir and would be expected to produce carbonation reaction fronts in cements that are relatively uniform as a function of depth.

  2. Wellbore cement fracture evolution at the cement–basalt caprock interface during geologic carbon sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hun Bok; Kabilan, Senthil; Carson, James P.; Kuprat, Andrew P.; Um, Wooyong; Martin, Paul F.; Dahl, Michael E.; Kafentzis, Tyler A.; Varga, Tamas; Stephens, Sean A.; Arey, Bruce W.; Carroll, KC; Bonneville, Alain; Fernandez, Carlos A.

    2014-08-07

    Composite Portland cement-basalt caprock cores with fractures, as well as neat Portland cement columns, were prepared to understand the geochemical and geomechanical effects on the integrity of wellbores with defects during geologic carbon sequestration. The samples were reacted with CO2-saturated groundwater at 50 ºC and 10 MPa for 3 months under static conditions, while one cement-basalt core was subjected to mechanical stress at 2.7 MPa before the CO2 reaction. Micro-XRD and SEM-EDS data collected along the cement-basalt interface after 3-month reaction with CO2-saturated groundwater indicate that carbonation of cement matrix was extensive with the precipitation of calcite, aragonite, and vaterite, whereas the alteration of basalt caprock was minor. X-ray microtomography (XMT) provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Computational fluid dynamics (CFD) modeling further revealed that this stress led to the increase in fluid flow and hence permeability. After the CO2-reaction, XMT images displayed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along the fracture located at the cement-basalt interface. The 3-D visualization and CFD modeling also showed that the precipitation of calcium carbonate within the cement fractures after the CO2-reaction resulted in the disconnection of cement fractures and permeability decrease. The permeability calculated based on CFD modeling was in agreement with the experimentally determined permeability. This study demonstrates that XMT imaging coupled with CFD modeling represent a powerful tool to visualize and quantify fracture evolution and permeability change in geologic materials and to predict their behavior during geologic carbon sequestration or hydraulic fracturing for shale gas production and enhanced geothermal systems.

  3. Was Mono Lake a 14C dump?

    Science.gov (United States)

    Maggs, William Ward

    This is a scientific story without an explanation, called a “mystery” and an “enigma” in articles by the people who discovered it. Confounded by evidence they cannot explain by natural processes, these scientists implicate human beings.One month ago in Eos, (June 7, 1988, p. 633), Wallace Broecker and Scott Stine reported abnormally high levels of radiogenic 14C in California's Mono Lake, now a National Historic Site. The only logical explanation, they proposed, is that someone secretly dumped a total of about 20 curies of 14C into the lake in two doses, sometime between 1952 and 1958 and again between 1966 and 1977. Broecker and Stine, geologists at Lamont-Doherty Geological Observatory in Palisades, N.Y., called on readers for information on the source of the 14C.

  4. Plasma etching on large-area mono-, multi- and quasi-mono crystalline silicon

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk; Boisen, Anja

    2013-01-01

    We use plasma etched Black Si (BS)[1][2] nanostructures to achieve low reflectance due to the resulting graded refractive index at the Si-air interface. The goal of this investigation is to develop a suitable texturing method for Si solar cells. Branz et al. [3]report below 3% average reflectance...... advantages such as; (i) excellent light trapping, (ii) dry, single-sided and scalable process method and (iii) etch independence on crystallinity of Si, RIE-texturing has so far not been proven superior to standard wet texturing, primarily as a result of lower power conversion efficiency due to increased...... using maskless RIE in a O2 and SF6 plasma, and the surface topology was optimized for solar cell applications by varying gas flows, pressure, power and process time. The starting substrates were 156x156 mm p-type, CZ mono-, multi- and quasi-mono crystalline Si wafers, respectively, with a thickness...

  5. Intercultural Interactions of Mono-Cultural, Mono-Lingual Local Students in Small Group Learning Activities: A Bourdieusian Analysis

    Science.gov (United States)

    Colvin, Cassandra; Fozdar, Farida; Volet, Simone

    2015-01-01

    This research examines the understandings and experiences of mono-cultural, mono-lingual local students in relation to intercultural interactions within small group learning activities at university. Bourdieu's concepts of field, habitus and capital are employed to illuminate a number of barriers to intercultural interaction. Using qualitative…

  6. Intercultural Interactions of Mono-Cultural, Mono-Lingual Local Students in Small Group Learning Activities: A Bourdieusian Analysis

    Science.gov (United States)

    Colvin, Cassandra; Fozdar, Farida; Volet, Simone

    2015-01-01

    This research examines the understandings and experiences of mono-cultural, mono-lingual local students in relation to intercultural interactions within small group learning activities at university. Bourdieu's concepts of field, habitus and capital are employed to illuminate a number of barriers to intercultural interaction. Using qualitative…

  7. Mono-dispersed cross-linked polystyrene micro-spheres prepared by seed swelling polymerization method

    Institute of Scientific and Technical Information of China (English)

    Dongsha WANG; Yanjun LIU

    2008-01-01

    A two-step swelling procedure was adopted to synthesize mono-dispersed and highly cross-linked poly (St-divinylbenzene) particles with PSt micro-spheres (1.80 μmin diameter). The PSt micro-spheres were prepared by a dispersion polymerization method and used as seeds. The effects of monomer concentration, ratio of ethanol to water, swelling reagents, crosslinking reagents, swelling temper-ature and agitation speed on particle size were investigated in detail. The morphologies and size distributions of these micro-spheres were examined by SEM and particle size analysis (PSA). The Tg of the micro-spheres was measured by DSC. The results indicate that the particles (6.20 μm in diameter) exhibit excellent mono dispersed property and high crosslinking degree when the concentration of the swelling reagent was 25%, the concentration of the cross-linking reagents was 23%, the swelling temperature was 30℃ and the stirring speed was 150 r/min.

  8. The truth about laser fiber diameters.

    Science.gov (United States)

    Kronenberg, Peter; Traxer, Olivier

    2014-12-01

    To measure the various diameters of laser fibers from various manufacturers and compare them with the advertised diameter. Fourteen different unused laser fibers from 6 leading manufacturers with advertised diameters of 200, 270, 272, 273, 365, and 400 μm were measured by light microscopy. The outer diameter (including the fiber coating, cladding, and core), cladding diameter (including the cladding and the fiber core), and core diameter were measured. Industry representatives of the manufacturers were interviewed about the diameter of their fibers. For all fibers, the outer and cladding diameters differed significantly from the advertised diameter (P cladding, and core diameters of fibers with equivalent advertised diameters differed by up to 180, 100, and 78 μm, respectively. Some 200-μm fibers had larger outer diameters than the 270- to 273-μm fibers. All packaging material and all laser fibers lacked clear and precise fiber diameter information labels. Of 12 representatives interviewed, 8, 3, and 1 considered the advertised diameter to be the outer, the cladding, and the core diameter, respectively. Representatives within the same company frequently gave different answers. This study suggests that, at present, there is a lack of uniformity between laser fiber manufacturers, and most of the information conveyed to urologists regarding laser fiber diameter may be incorrect. Because fibers larger than the advertised laser fibers are known to influence key interventional parameters, this misinformation can have surgical repercussions. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Imaging wellbore cement degradation by carbon dioxide under geologic sequestration conditions using X-ray computed microtomography.

    Science.gov (United States)

    Jung, Hun Bok; Jansik, Danielle; Um, Wooyong

    2013-01-02

    X-ray microtomography (XMT), a nondestructive three-dimensional imaging technique, was applied to demonstrate its capability to visualize the mineralogical alteration and microstructure changes in hydrated Portland cement exposed to carbon dioxide under geologic sequestration conditions. Steel coupons and basalt fragments were added to the cement paste in order to simulate cement-steel and cement-rock interfaces. XMT image analysis showed the changes of material density and porosity in the degradation front (density: 1.98 g/cm(3), porosity: 40%) and the carbonated zone (density: 2.27 g/cm(3), porosity: 23%) after reaction with CO(2)-saturated water for 5 months compared to unaltered cement (density: 2.15 g/cm(3), porosity: 30%). Three-dimensional XMT imaging was capable of displaying spatially heterogeneous alteration in cement pores, calcium carbonate precipitation in cement cracks, and preferential cement alteration along the cement-steel and cement-rock interfaces. This result also indicates that the interface between cement and host rock or steel casing is likely more vulnerable to a CO(2) attack than the cement matrix in a wellbore environment. It is shown here that XMT imaging can potentially provide a new insight into the physical and chemical degradation of wellbore cement by CO(2) leakage.

  10. Professional Android Programming with Mono for Android and NETC#

    CERN Document Server

    McClure, Wallace B; Croft, John J; Dick, Jonathan; Hardy, Chris

    2012-01-01

    A one-of-a-kind book on Android application development with Mono for Android The wait is over! For the millions of .NET/C# developers who have been eagerly awaiting the book that will guide them through the white-hot field of Android application programming, this is the book. As the first guide to focus on Mono for Android, this must-have resource dives into writing applications against Mono with C# and compiling executables that run on the Android family of devices. Putting the proven Wrox Professional format into practice, the authors provide you with the knowledge you need to become a succ

  11. The wellbore simulator SIMU1999; El simulador de pozos SIMU1999

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Upton, Pedro [Comision Federal de Electricidad, Morelia, Michoacan (Mexico)

    1999-08-01

    This work presents a brief description of the architecture and scope of the wellbore simulator SIMU1999. Its prime application involves the representation of the different flow types and thermodynamic conditions found in geothermal wells. The simulator utilizes a homogeneous flow model which incorporates the fundamental theories of fluid mechanics and allows the handling of two-phase three component mixtures (H{sub 2}O-NaCl-CO{sub 2}), which represent the main constituents appearing in the production of geothermal fluids. SIMU1999 uses a two-phase friction factor developed on the basis of 64 production test carried out on 45 different wells. There were recovered more than 324 pressure drop data and 628 temperature measurements from the inner of the wells. Mechanical log recorders (Kuster) were mainly used but some electronic logs (Hot Hole and Pruett) were carried out, too. The friction factor is calculated using the Reynolds number, steam quality, and fluid pressure, therefore, it is independent of any previous flow pattern identification. Production data included specific enthalpies from 650 to 2 780 kj/kg, fluid pressures between 0.4 and 14 MPa, and fluid temperatures from 110 to 340 Celsius degrees. The computer code of SIMU 1999 is written in Fortran 90 and generates and executable file a little bit greater than 1 Mb. The program is divided in four parts, these are: the wellbore simulator; a graphical output to analyze the results on the screen; a separated subroutine to evaluate the mass flow rate of three component flows discharging to the atmosphere at the speed of sound; and an independent thermodynamic module which could be utilized to make estimations to be used in manual analysis. The code incorporates an efficient algorithm to solve the fluid transport phenomena problem, based on a numerical method of successive approaches. The simulator uses the International System of Units, for data input and for results (outcomes) generation. Everything is realized

  12. Greater Sage-grouse Telemetry - Mono Co. [ds68

    Data.gov (United States)

    California Department of Resources — Combined telemetry locations for sage grouse in Mono County which were fitted with radio-transmitters for the USGS Greater sage-grouse project. Contains spatial and...

  13. 1:1 scale wellbore experiment and associated modeling for a better understanding of well integrity in the context of CO2 geological storage

    NARCIS (Netherlands)

    Manceau, J.C.; Trémosa, J.; Audigane, P.; Claret, F.; Wasch, L.J.; Gherardi, F.; Ukelis, O.; Dimier, A.; Nussbaum, C.; Lettry, Y.; Fierz, T.

    2014-01-01

    In this study, we present a new experiment for following the evolution of the well integrity over time due to different changes in well conditions (pressure, temperature and fluids in contact with the well) in the context of CO2 geological storage. A small section of a wellbore is reproduced in the

  14. Hydrated Ordinary Portland Cement as a Carbonic Cement: The Mechanisms, Dynamics, and Implications of Self-Sealing and CO2 Resistance in Wellbore Cements

    Energy Technology Data Exchange (ETDEWEB)

    Guthrie, George Drake Jr. [Los Alamos National Laboratory; Pawar, Rajesh J. [Los Alamos National Laboratory; Carey, James William [Los Alamos National Laboratory; Karra, Satish [Los Alamos National Laboratory; Harp, Dylan Robert [Los Alamos National Laboratory; Viswanathan, Hari S. [Los Alamos National Laboratory

    2017-07-28

    This report analyzes the dynamics and mechanisms of the interactions of carbonated brine with hydrated Portland cement. The analysis is based on a recent set of comprehensive reactive-transport simulations, and it relies heavily on the synthesis of the body of work on wellbore integrity that we have conducted for the Carbon Storage Program over the past decade.

  15. New mono-organotin (IV) dithiocarbamate complexes

    Science.gov (United States)

    Muthalib, Amirah Faizah Abdul; Baba, Ibrahim

    2014-09-01

    Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S2CNR'R″]2 (R= Ph, CH3, R' = CH3, C2H5, C7H7 and R″ = C2H5, C6H11, iC3H7, C7H7). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, 1H, 13C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(CN), ν(CS) and ν(Sn-S) band which present in the region of 1444-1519, 954-1098 and 318-349 cm-1 respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of NCS group in the range of 253 - 259 nm due to the intramolecular charge transfer of the ligand. The 13C NMR spectra showed an important shift for δ(N13CS2) in the range of 196.8 - 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S2CN(Et)(i-Pr)]2, MeSnCl[S2CN(Me)(Cy)]2 and MeSnCl[S2CN(i-Pr)(CH2Ph)]2. All structures having a distorted octahedral geometry set by CClS4 donor atom from the two chelating dithiocarbamate ligands.

  16. T2Well/ECO2N Version 1.0: Multiphase and Non-Isothermal Model for Coupled Wellbore-Reservoir Flow of Carbon Dioxide and Variable Salinity Water

    Energy Technology Data Exchange (ETDEWEB)

    Pan, L.; Oldenburg, C.M.; Wu, Y.-S.; Pruess, K.

    2011-02-14

    At its most basic level, the injection of CO{sub 2} into geologic CO{sub 2} storage sites involves a system comprising the wellbore and the target reservoir. The wellbore is the only conduit available to emplace CO{sub 2} into reservoirs for long-term storage. At the same time, wellbores in general have been identified as the most likely conduit for CO{sub 2} and brine leakage from geologic carbon sequestration (GCS) sites, especially those in sedimentary basins with historical hydrocarbon production. We have developed a coupled wellbore and reservoir model for simulating the dynamics of CO{sub 2} injection and leakage through wellbores. The model describes the following processes: (1) upward or downward wellbore flow of CO{sub 2} and variable salinity water with transition from supercritical to gaseous CO{sub 2} including Joule-Thomson cooling, (2) exsolution of CO{sub 2} from the aqueous phase as pressure drops, and (3) cross flow into or interaction with layers of surrounding rock (reservoirs). We use the Drift-Flux Model and related conservation equations for describing transient two-phase non-isothermal wellbore flow of CO{sub 2}-water mixtures under different flow regimes and interacting with surrounding rock. The mass and thermal energy balance equations are solved numerically by a finite difference scheme with wellbore heat transmission to the surrounding rock handled either semi-analytically or numerically. The momentum balance equation for the flow in the wellbore is solved numerically with a semi-explicit scheme. This manual provides instructions for compilation and use of the new model, and presents some example problems to demonstrate its use.

  17. Seed mediated synthesis of highly mono-dispersed gold nanoparticles in the presence of hydroquinone

    Science.gov (United States)

    Kumar, Dhiraj; Mutreja, Isha; Sykes, Peter

    2016-09-01

    Gold nanoparticles (AuNPs) are being studied for several biomedical applications, including drug delivery, biomedical imaging, contrast agents and tumor targeting. The synthesis of nanoparticles with a narrow size distribution is critical for these applications. We report the synthesis of highly mono-dispersed AuNPs by a seed mediated approach, in the presence of tri-sodium citrate and hydroquinone (HQ). AuNPs with an average size of 18 nm were used for the synthesis of highly mono-dispersed nanocrystals of an average size 40 nm, 60 nm, 80 nm and ˜100 nm; but the protocol is not limited to these sizes. The colloidal gold was subjected to UV-vis absorbance spectroscopy, showing a red shift in lambda max wavelength, peaks at 518.47 nm, 526.37 nm, 535.73 nm, 546.03 nm and 556.50 nm for AuNPs seed (18 nm), 40 nm, 60 nm, 80 nm and ˜100 nm respectively. The analysis was consistent with dynamic light scattering and electron microscopy. Hydrodynamic diameters measured were 17.6 nm, 40.8 nm, 59.8 nm, 74.1 nm, and 91.4 nm (size by dynamic light scattering—volume %); with an average poly dispersity index value of 0.088, suggesting mono-dispersity in the size distribution, which was also confirmed by transmission electron microscopy analysis. The advantage of a seed mediated approach is a multi-step growth of nanoparticle size that enables us to control the number of nanoparticles in the suspension, for size ranging from 24.5 nm to 95.8 nm. In addition, the HQ-based synthesis of colloidal nanocrystals allowed control of the particle size and size distribution by tailoring either the number of seeds, amount of gold precursor or reducing agent (HQ) in the final reaction mixture.

  18. Seed mediated synthesis of highly mono-dispersed gold nanoparticles in the presence of hydroquinone.

    Science.gov (United States)

    Kumar, Dhiraj; Mutreja, Isha; Sykes, Peter

    2016-09-02

    Gold nanoparticles (AuNPs) are being studied for several biomedical applications, including drug delivery, biomedical imaging, contrast agents and tumor targeting. The synthesis of nanoparticles with a narrow size distribution is critical for these applications. We report the synthesis of highly mono-dispersed AuNPs by a seed mediated approach, in the presence of tri-sodium citrate and hydroquinone (HQ). AuNPs with an average size of 18 nm were used for the synthesis of highly mono-dispersed nanocrystals of an average size 40 nm, 60 nm, 80 nm and ∼100 nm; but the protocol is not limited to these sizes. The colloidal gold was subjected to UV-vis absorbance spectroscopy, showing a red shift in lambda max wavelength, peaks at 518.47 nm, 526.37 nm, 535.73 nm, 546.03 nm and 556.50 nm for AuNPs seed (18 nm), 40 nm, 60 nm, 80 nm and ∼100 nm respectively. The analysis was consistent with dynamic light scattering and electron microscopy. Hydrodynamic diameters measured were 17.6 nm, 40.8 nm, 59.8 nm, 74.1 nm, and 91.4 nm (size by dynamic light scattering-volume %); with an average poly dispersity index value of 0.088, suggesting mono-dispersity in the size distribution, which was also confirmed by transmission electron microscopy analysis. The advantage of a seed mediated approach is a multi-step growth of nanoparticle size that enables us to control the number of nanoparticles in the suspension, for size ranging from 24.5 nm to 95.8 nm. In addition, the HQ-based synthesis of colloidal nanocrystals allowed control of the particle size and size distribution by tailoring either the number of seeds, amount of gold precursor or reducing agent (HQ) in the final reaction mixture.

  19. Measuring water quality from individual fractures in open wellbores using hydraulic isolation and the dissolved oxygen alteration method

    Science.gov (United States)

    Vitale, Sarah A.; Robbins, Gary A.

    2017-08-01

    This study describes a low-cost method for sampling individual fractures in open wellbores in crystalline bedrock utilizing naturally occurring flow conditions in the well. The method entails using the dissolved oxygen alteration method (DOAM) to identify transmissive fractures and vertical flow direction. After obtaining information about relative hydraulic gradients, flow direction in the well is modified using a single control pump to isolate fractures of interest for sampling. Additional dissolved oxygen, injected during the DOAM procedure, serves as a tracer to ensure the water quality in the sampling zone is characteristic of the fracture of interest by requiring a tracer-free zone prior to sampling. Sampling procedures are described conceptually for nine bedrock wells with varying flow conditions containing one, two, or three transmissive inflowing fractures. The method was demonstrated in two crystalline bedrock wells containing one and two transmissive inflowing fractures.

  20. New mono-organotin (IV) dithiocarbamate complexes

    Energy Technology Data Exchange (ETDEWEB)

    Muthalib, Amirah Faizah Abdul; Baba, Ibrahim [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi (Malaysia)

    2014-09-03

    Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S{sub 2}CNR′R″]{sub 2} (R= Ph, CH{sub 3}, R′ = CH{sub 3}, C{sub 2}H{sub 5}, C{sub 7}H{sub 7} and R″ = C{sub 2}H{sub 5}, C{sub 6}H{sub 11}, iC{sub 3}H{sub 7}, C{sub 7}H{sub 7}). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, {sup 1}H, {sup 13}C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(CN), ν(CS) and ν(Sn-S) band which present in the region of 1444–1519, 954–1098 and 318–349 cm{sup −1} respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of NCS group in the range of 253 – 259 nm due to the intramolecular charge transfer of the ligand. The {sup 13}C NMR spectra showed an important shift for δ(N{sup 13}CS{sub 2}) in the range of 196.8 – 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S{sub 2}CN(Et)(i−Pr)]{sub 2}, MeSnCl[S{sub 2}CN(Me)(Cy)]{sub 2} and MeSnCl[S{sub 2}CN(i−Pr)(CH{sub 2}Ph)]{sub 2}. All structures having a distorted octahedral geometry set by CClS{sub 4} donor atom from the two

  1. MWD tool for deep, small diameter boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Buytaert, J.P.R.; Duckworth, A.

    1992-03-17

    This patent describes an apparatus for measuring a drilling parameters while drilling a borehole in an earth formation, wherein the borehole includes a small diameter deep borehole portion and a large diameter upper borehole portion. It includes small diameter drillstring means for drilling the deep borehole portion; sensor means, disposed within the small diameter drillstring means, for measuring a drilling parameter characteristic of the deep portion of the borehole while drilling the deep portion of the borehole and for providing sensor output signals indicative of the measured parameter; an upper drillstring portion extending between the surface of the formation and the small diameter drillstring means, the upper drillstring portion including a large diameter drillstring portion; data transmission means disposed within the large diameter drillstring portion and responsive to the sensor output.

  2. Pairing preferences of the model mono-valence mono-atomic ions investigated by molecular simulation.

    Science.gov (United States)

    Zhang, Qiang; Zhang, Ruiting; Zhao, Ying; Li, HuanHuan; Gao, Yi Qin; Zhuang, Wei

    2014-05-14

    We carried out a series of potential of mean force calculations to study the pairing preferences of a series of model mono-atomic 1:1 ions with evenly varied sizes. The probabilities of forming the contact ion pair (CIP) and the single water separate ion pair (SIP) were presented in the two-dimensional plots with respect to the ion sizes. The pairing preferences reflected in these plots largely agree with the empirical rule of matching ion sizes in the small and big size regions. In the region that the ion sizes are close to the size of the water molecule; however, a significant deviation from this conventional rule is observed. Our further analysis indicated that this deviation originates from the competition between CIP and the water bridging SIP state. The competition is mainly an enthalpy modulated phenomenon in which the existing of the water bridging plays a significant role.

  3. Degenerate gaugino mass region and mono-boson collider signatures

    CERN Document Server

    Anandakrishnan, Archana; Raby, Stuart

    2014-01-01

    In this paper we discuss search strategies at the LHC for light electroweak gauginos which are mostly Wino-like, Higgsino-like or an admixture. These states are typically degenerate with decay products that are less energetic and hence difficult to detect. In addition, their production cross-sections at a hadron collider are suppressed compared to colored states such as the gluinos. In order to detect these states one needs to trigger on initial or final state radiation. Many previous analyses have focussed on mono-jet and mono-photon triggers. In the paper we argue and show that these triggers are unlikely to succeed, due to the large background from QCD backgrounds for the mono-jet searches and the fact that the $p_T$ distribution of the mono-photons are rapidly decreasing functions of $p_T$. We show this with both an analytic calculation of photons in the initial state radiation and also a detailed numerical analysis. We then argue that mono-Z triggers, from Z decaying into charged leptons may well provide...

  4. Mono- and bi-functional arenethiols as surfactants for gold nanoparticles: synthesis and characterization

    Directory of Open Access Journals (Sweden)

    Fratoddi Ilaria

    2011-01-01

    Full Text Available Abstract Stable gold nanoparticles stabilized by different mono and bi-functional arenethiols, namely, benzylthiol and 1,4-benzenedimethanethiol, have been prepared by using a modified Brust's two-phase synthesis. The size, shape, and crystalline structure of the gold nanoparticles have been determined by high-resolution electron microscopy and full-pattern X-ray powder diffraction analyses. Nanocrystals diameters have been tuned in the range 2 ÷ 9 nm by a proper variation of Au/S molar ratio. The chemical composition of gold nanoparticles and their interaction with thiols have been investigated by X-ray photoelectron spectroscopy. In particular, the formation of networks has been observed with interconnected gold nanoparticles containing 1,4-benzenedimethanethiol as ligand.

  5. Fatigue Analysis of a Mono-Tower Platform

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Brincker, Rune

    In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed thro...... of the natural period, damping ratio, current, stress Spectrum and parameters describing the fatigue strength. Further, soil damping is shown to be significant for the Mono-tower.......In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed...

  6. Fatigue Reliability Analysis of a Mono-Tower Platform

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Brincker, Rune

    1991-01-01

    In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed thro...... of the natural period, damping ratio, current, stress spectrum and parameters describing the fatigue strength. Further, soil damping is shown to be significant for the Mono-tower.......In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed...

  7. Extraction of mono- and dicarboxylic acids from a curative water.

    Science.gov (United States)

    Franke, C; Weil, L; Niessner, R

    1995-09-01

    A method for the analysis of mono- and dicarboxylic acids from water is presented. For this purpose two techniques, a C(18) solid phase extraction (SPE) and a combination method of liquid-liquid extraction (LLE) and aminopropyl SPE, were tested. With the combination method all analytes, short-chain mono- and long-chain dicarboxylic acids, could be analysed in one approach. The C(18) SPE was not suitable for short-chain mono- but for dicarboxylic acids. Concentrations in the investigated water ranged from 315 mg/l (butanoic acid) to 2.9 mg/l (octanoic acid). Dicarboxylic acids were found from 5 mg/l (octanedioic acid) to 0.5 mg/l (dodecanedioic acid).

  8. Reliability Analysis of a Mono-Tower Platform

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Enevoldsen, I.; Sørensen, John Dalsgaard;

    In this paper a reliability analysis of a Mono-tower platform is presented. The failure modes, considered, are yelding in the tube cross-sections, and fatigue failure in the butt welds. The fatigue failure mode is investigated with a fatigue model, where the fatigue strength is expressed through SN...... for the fatigue limit state is a significant failure mode for the Mono.tower platform. Further, it is shown for the fatigue failure mode the the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties...

  9. Reliability Analysis of a Mono-Tower Platform

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Enevoldsen, I.; Sørensen, John Dalsgaard;

    1990-01-01

    In this paper, a reliability analysis of a Mono-tower platform is presented. Te failure modes considered are yielding in the tube cross sections and fatigue failure in the butts welds. The fatigue failrue mode is investigated with a fatigue model, where the fatigue strength is expressed through SN...... that the fatigue limit state is a significant failure mode for the Mono-tower platform. Further, it is shown for the fatigue failure mode that the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties...

  10. Cost-Effective Mass Production of Mono Bucket Foundations

    DEFF Research Database (Denmark)

    Gres, Szymon; Nielsen, Søren Andreas; Fejerskov, Morten

    2015-01-01

    No recognized procedures exist for the Mono Bucket Foundation design, which is an obstruction for mass customization/production and industrialization in relation to certifying authorities. This paper presents the outcome of on-going research and development program that provides solution for inno......No recognized procedures exist for the Mono Bucket Foundation design, which is an obstruction for mass customization/production and industrialization in relation to certifying authorities. This paper presents the outcome of on-going research and development program that provides solution...

  11. Subnanometer-Diameter Wires Isolated in a Polymer Matrix by Fast Polymerization

    Science.gov (United States)

    Golden; DiSalvo; Frechet; Silcox; Thomas; Elman

    1996-08-09

    The preparation and analysis of inorganic-organic polymer nanocomposites consisting of inorganic nanowires and multiwire "cables" in a random-coil organic polymer host is reported. Dissolution of inorganic (LiMo3Se3)n wires in a strongly coordinating monomer, vinylene carbonate, and the use of a rapid polymerization in the presence of a cross-linking agent produce nanocomposites without phase separation. Polymerization of dilute solutions yields a material containing mostly (Mo3Se3(-))n mono- and biwires, 6 to 20 angstroms in diameter and 50 to 100 nanometers long. Polymerization of more concentrated liquid crystalline solutions yields a nanocomposite containing oriented multiwire cables, 20 to 40 angstroms in diameter and up to 1500 nanometers long, that display optical anisotropy and electrical conductivity.

  12. 7 CFR 51.2850 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Diameter. Diameter means the greatest dimension measured at right angles to a straight line running from...

  13. 7 CFR 51.712 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... § 51.712 Diameter. Diameter means the greatest dimension measured at right angles to a line from stem...

  14. 7 CFR 51.651 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946...) Definitions § 51.651 Diameter. Diameter means the greatest dimension measured at right angles to a line from...

  15. Measuring angular diameters of extended sources

    NARCIS (Netherlands)

    van Hoof, PAM

    2000-01-01

    When measuring diameters of partially resolved sources like planetary nebulae, H II regions or galaxies, often a technique called Gaussian deconvolution is used. This technique yields a Gaussian diameter, which subsequently has to be multiplied by a conversion factor to obtain the true angular

  16. Plasma etching on large-area mono-, multi- and quasi-mono crystalline silicon

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk; Boisen, Anja

    2013-01-01

    We use plasma etched Black Si (BS)[1][2] nanostructures to achieve low reflectance due to the resulting graded refractive index at the Si-air interface. The goal of this investigation is to develop a suitable texturing method for Si solar cells. Branz et al. [3]report below 3% average reflectance...... for their 16.8% efficient black Si cell using a metal-assisted, chemical etching method on FZ mono-crystalline Si substrates. Yoo et al. [4] use RIE similar to this work on large-area, multi-crystalline Si cells and achieve a 16.1% efficiency despite a relatively high reflectance of 13.3%. Despite several...... advantages such as; (i) excellent light trapping, (ii) dry, single-sided and scalable process method and (iii) etch independence on crystallinity of Si, RIE-texturing has so far not been proven superior to standard wet texturing, primarily as a result of lower power conversion efficiency due to increased...

  17. 21 CFR 184.1505 - Mono- and diglycerides.

    Science.gov (United States)

    2010-04-01

    ... prepared from fats or oils or fat-forming acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in...

  18. Tagging a mono-top signature in Natural SUSY

    CERN Document Server

    Goncalves, Dorival; Takeuchi, Michihisa

    2016-01-01

    We study the feasibility of probing a region of Natural Supersymmetry where the stop and higgsino masses are compressed. Although this region is most effectively searched for in the mono-jet channel, this signature is present in many other non-supersymmetric frameworks. Therefore, another channel that carries orthogonal information is required to confirm the existence of the light stop and higgsinos. We show that a supersymmetric version of the $t \\bar t H$ process, $pp \\to t \\tilde t_1 \\tilde \\chi^0_{1(2)}$, can have observably large rate when both the stop and higgsinos are significantly light, and it leads to a distinctive mono-top signature in the compressed mass region. We demonstrate that the hadronic channel of the mono-top signature can effectively discriminate the signal from backgrounds by tagging a hadronic top-jet. We show that the hadronic channel of mono-top signature offers a significant improvement over the leptonic channel and the sensitivity reaches $m_{\\tilde t_1} \\simeq 420$ GeV at the 13 ...

  19. Spin, Charge, and Bonding in Transition Metal Mono Silicides

    NARCIS (Netherlands)

    Marel, D. van der; Damascelli, A.; Schulte, K.; Menovsky, A. A.

    1997-01-01

    Published in: Physica B 244 (1998) 138-147 citations recorded in [Science Citation Index] Abstract: We review some of the relevant physical properties of the transition metal mono-silicides with the FeSi structure (CrSi, MnSi, FeSi, CoSi, NiSi, etc) and explore the relation between their structural

  20. IRIS Toxicological Review of Ethylene Glycol Mono Butyl ...

    Science.gov (United States)

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health. N/A

  1. Transient Monotonic and Cyclic Load Effects on Mono Bucket Foundations

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam

    and when hitting the foundation they induce high impact loads with a short duration. It is important that the foundation is able to resists these huge loads. Fortunately, the conducted research showed that the capacity of the mono bucket foundation is high to impact loads. When exposed to a huge wave load...

  2. Temperature dependence of atomic vibrations in mono-layer graphene

    NARCIS (Netherlands)

    Allen, C.S.; Liberti, E.; Kim, J.S.; Xu, Q.; Fan, Y.; He, K.; Robertson, A.W.; Zandbergen, H.W.; Warner, J.H.; Kirkland, A.I.

    2015-01-01

    We have measured the mean square amplitude of both in- and out-of-plane lattice vibrations for mono-layer graphene at temperatures ranging from ∼100 K to 1300 K. The amplitude of lattice vibrations was calculated from data extracted from selected area electron diffraction patterns recorded across a

  3. Characterization of the interaction of a mono-6-thio-β-cyclodextrin-capped CdTe quantum dots-methylene blue/methylene green system with herring sperm DNA using a spectroscopic approach.

    Science.gov (United States)

    Shen, Yizhong; Liu, Shaopu; Wang, Lei; Yin, Pengfei; He, Youqiu

    2014-11-01

    Novel, water-soluble CdTe quantum dots (QDs) capped with β-cyclodextrin (β-CD) and ~ 4.0 nm in diameter were synthesized in aqueous solution, and characterized using transmission electron microscopy (TEM). A fluorescence-sensing system based on the photoinduced electron transfer (PET) of (mono-6-thio-β-CD)-CdTe QDs was then designed to measure the interaction of phenothiazine dyes [methylene blue (MB) and methylene green (MG)] with herring sperm DNA (hsDNA). This fluorescence-sensing system was based on a fluorescence "OFF-ON" mode. First, MB/MG adsorbed on the surface of (mono-6-thio-β-CD)-CdTe QDs effectively quenches the fluorescence of (mono-6-thio-β-CD)-CdTe QDs through PET. Then, addition of hsDNA restores the fluorescence intensity of (mono-6-thio-β-CD)-CdTe QDs, because hsDNA can bind with MB/MG and remove it from the as-prepared (mono-6-thio-β-CD)-CdTe QDs. In addition, detailed reaction mechanisms of the (mono-6-thio-β-CD)-CdTe QDs-MB/MG-hsDNA solution system were studied using optical methods, by comparison with the TGA-CdTe QDs-MB/MG-hsDNA solution system. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Quaternary Eruptions of the Mono-Inyo Craters, California

    Science.gov (United States)

    Bursik, M. I.; Pouget, S.; Mangan, M.; Marcaida, M.; Vazquez, J. A.

    2013-12-01

    The eruptive products of the Mono-Inyo Craters volcanic chain include the tephra and associated volcanic rocks of Black Point, islands of Mono Lake, Mono Craters, Inyo Craters, late eruptions of Mammoth Mountain and Red Cones. Most of the eruptions were explosive, and generated numerous pyroclastic flows, surges and falls as well as the prominent domes and lava flows that now cover vents. The eruptions range in age from several hundred years to at least 60,000 yr BP. The Mono-Inyo tephras are dispersed throughout the Sierra Nevada and Basin and Range, providing key time-stratigraphic marker layers. Recent work has not only resulted in high-precision radiometric dating of many of the tephras, but also detailed geochemical data that for the first time provides fingerprinting sufficiently precise to discriminate among the tephras. Lithostratigraphy of many of the layers is herein described for the first time, based on careful sampling and description in the field, and laboratory grain size, grain shape and componentry analyses of the late Pleistocene tephras of the Wilson Creek Formation. Most of the Wilson Creek volcanic layers are fall deposits accumulated within paleolake Russell, which were generated by eruptions of variable intensity and influenced by paleowinds of different orientation. Prevailing winds were generally to the North and East, but often the Pleistocene layers less than 25 ka were dispersed to the West. Many of the fall layers show evidence of wave reworking, generally near the top, although in some cases it is pervasive. Only near the vent do some layers of apparent debris flow origin occur. Maximum pumice sizes range up to nearly 3 cm, and lithics range up to 1 cm in the rhyolitic fall beds, while thicknesses range up to c. 30 cm. These data are consistent with relatively low volume, subplinian style eruptive behavior for most of the life of the Mono-Inyo Craters.

  5. Pyrogen testing of lipid-based TPN using Mono Mac 6 monocyte cell line and DELFIA

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    1997-01-01

    Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells.......Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells....

  6. Mechanical Behavior and Permeability Evolution of Reconstituted Coal Samples under Various Unloading Confining Pressures—Implications for Wellbore Stability Analysis

    Directory of Open Access Journals (Sweden)

    Qiangui Zhang

    2017-03-01

    Full Text Available Low pressure, low permeability, and low saturation of Chinese coal-bed methane (CBM reservoirs make underbalanced drilling (UBD widely used for mining CBM in China. In this study, mechanical behavior and permeability of coal rock were investigated under different degrees of unloading confining pressure (UCP-reloading axial stress (RAS by a triaxial experimental apparatus. These tests revealed that: (1 peak deviatoric stress of coal rock in UCP-RAS is lower than that in a conventional triaxial compression (CTC test, and the peak deviatoric stress linearly relates the degree of unloading confining pressure. The deformation modulus of coal in UCP-RAS is lower than that in CTC, while the lateral expansion ratio is larger than that in CTC; (2 higher UCP leads to a faster increase of permeability during RAS until the failure of coal; (3 the cohesion and internal friction angle tested by UCP-RAS are lower by 4.57% and 15.18% than those tested by CTC. In addition, a field case (Zhaozhuang well, Qinshui Basin, China of a well collapse problem validates the higher probability of wellbore collapse due to the increase of equivalent collapse fluid density, which is calculated by using coal rock parameters tested by UCP-RAS rather than by CTC.

  7. A Study of Production/Injection Data from Slim Holes and Large-Diameter Wells at the Okuaizu Geothermal Field, Tohoku, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Joel Lawrence; Garg, Sabodh K.; Combs, Jim

    2002-06-01

    Discharge from the Okuaizu boreholes is accompanied by in situ boiling. Analysis of cold-water injection and discharge data from the Okuaizu boreholes indicates that the two-phase productivity index is about an order of magnitude smaller than the injectivity index. The latter conclusion is in agreement with analyses of similar data from Oguni, Sumikawa, and Kirishima geothermal fields. A wellbore simulator was used to examine the effect of borehole diameter on the discharge capacity of geothermal boreholes with two-phase feedzones. Based on these analyses, it appears that it should be possible to deduce the discharge characteristics of largediameter wells using test data from slim holes with two-phase feeds.

  8. Impact Structures: What Does Crater Diameter Mean?

    Science.gov (United States)

    Turtle, E. P.; Pierazzo, E.; Collins, G. S.; Osinski, G. R.; Melosh, H. J.; Morgan, J. V.; Reimold, W. U.; Spray, J. G.

    2004-03-01

    Crater diameter is an important parameter in energy scaling and impact simulations. However, disparate types of data make the use of consistent metrics difficult. We suggest a consistent terminology and discuss it in the context of several examples.

  9. Defining a Minimum End Mill Diameter

    Directory of Open Access Journals (Sweden)

    A. E. Dreval'

    2015-01-01

    Full Text Available Industrial observations show that the standard mill designs in many cases do not provide a complete diversity of manufacturing operations, and a lot of enterprises are forced to design and manufacture special (original designs of tools. The information search has revealed a lack of end mill diameter calculations in publications. There is a proposal to calculate the end mill diameter either by empirical formulas [2, 3], or by selection from the tables [4].To estimate a minimum diameter of the end mill to perform the specified manufacturing operations based on the mill body strength the formulas are obtained. The initial data for calculation are the flow sheet of milling operation and properties of processed and tool materials. The end mill is regarded, as a cantilevered beam of the circular cross section having Dс diameter (mill core diameter with overhang Lв from rigid fixing and loaded by the maximum bending force and torque.In deriving the formulas were used the following well-reasoned assumptions based on the analysed sizes of the structural elements of the standard mills: a diameter of mill core is linearly dependent on the mill diameter and the overhang; the 4τ 2 to σ 2 4τ2 ratio is constant and equal to 0.065 for contour milling and 0.17 for slot milling.The formulas for calculating the minimum diameter are as follows:  3 обр в 1 121 1.1  K S L L D m C z    for contour milling;  3 обр в 1 207 1.1  K S L L D m C z    for slot milling.Obtained dependences that allow defining a minimum diameter of the end mill in terms of ensuring its strength can be used to design mills for contour milling with radius transition sections, holes of different diameters in the body parts and other cases when for processing a singlemill is preferable.Using the proposed dependencies for calculating a feed of the maximum tolerable strength is reasonable in designing the mills for slots.Assumptions used in deriving

  10. Unit distances and diameters in Euclidean spaces

    CERN Document Server

    Swanepoel, Konrad J

    2007-01-01

    We show that the maximum number of unit distances or of diameters in a set of n points in d-dimensional Euclidean space is attained only by specific types of Lenz constructions, for all d >= 4 and n sufficiently large, depending on d. As a corollary we determine the exact maximum number of unit distances for all even d >= 6, and the exact maximum number of diameters for all d >= 4, for all $n$ sufficiently large, depending on d.

  11. Shaft Diameter Measurement Using Structured Light Vision

    OpenAIRE

    2015-01-01

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is meas...

  12. Appendiceal diameter: CT versus sonographic measurements

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-03-15

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

  13. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Diacetyl tartaric acid esters of mono- and... acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed esters of glycerin in which one or more of the hydroxyl...

  14. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for the...

  15. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Propylene glycol mono- and diesters of fats and... DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.856 Propylene glycol mono- and diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be...

  16. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Polyethylene glycol (400) mono- and dioleate. 573... DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following...

  17. Permeability of mono- and bi-dispersed porous media

    Directory of Open Access Journals (Sweden)

    Kim S.J.

    2013-04-01

    Full Text Available In this study, the permeability of mono- and bi-dispersed porous media is considered. The effects of the particle size distribution and the packing structure of particles on the permeability are investigated experimentally and analytically. Both experimental and analytic results suggest that the particlesize distribution is close to the log-normal distribution, and the permeability of the mono-dispersed porous media quasi-linearly decreases as the range of the particle size distribution increases. On the other hand, the effect of packing structure of particles on the permeability is shown to be negligible.The permeability of the bidispersed porous media quasi-linearly decreases as the range of cluster size increases, and nearly independent of the particle size distribution. The present model is valid over the range of parameters typically found in heat transfer applications.

  18. Mono Lake Analog Mars Sample Return Expedition for AMASE

    Science.gov (United States)

    Conrad, P. G.; Steele, A.; Younse, P.; DiCicco, M.; Morgan, A. R.; Backes, P.; Eigenbrode, J. E.; Marquardt, D.; Amundsen, H. E. F.

    2011-01-01

    We explored the performance of one robotic prototype for sample acquisition and caching of martian materials that has been developed at the Jet Propulsion Laboratory for potential use in the proposed MAX-C Mars Sample Return architecture in an environment, rich in chemical diversity with a variety of mineralogical textures. Mono Lake State Tufa Reserve in Mono County, CA possesses a variety of minerals including a variety of evaporites, volcanic glass and lava, and sand and mudstones. The lake itself is an interesting chemical system: the water is highly alkaline (pH is approximately 10) and contains concentrations of Cl, K, B, with lesser amounts of S Ca Mg, F, As, Li, I and Wand generally enriched HREEs. There are also traces of radioactive elements U, Th, Pl.

  19. Collagen fibril diameter and leather strength.

    Science.gov (United States)

    Wells, Hannah C; Edmonds, Richard L; Kirby, Nigel; Hawley, Adrian; Mudie, Stephen T; Haverkamp, Richard G

    2013-11-27

    The main structural component of leather and skin is type I collagen in the form of strong fibrils. Strength is an important property of leather, and the way in which collagen contributes to the strength is not fully understood. Synchrotron-based small angle X-ray scattering (SAXS) is used to measure the collagen fibril diameter of leather from a range of animals, including sheep and cattle, that had a range of tear strengths. SAXS data were fit to a cylinder model. The collagen fibril diameter and tear strength were found to be correlated in bovine leather (r(2) = 0.59; P = 0.009), with stronger leather having thicker fibrils. There was no correlation between orientation index, i.e., fibril alignment, and fibril diameter for this data set. Ovine leather showed no correlation between tear strength and fibril diameter, nor was there a correlation across a selection of other animal leathers. The findings presented here suggest that there may be a different structural motif in skin compared with tendon, particularly ovine skin or leather, in which the diameter of the individual fibrils contributes less to strength than fibril alignment does.

  20. Modification and performance evaluation of a mono-valve engine

    Science.gov (United States)

    Behrens, Justin W.

    A four-stroke engine utilizing one tappet valve for both the intake and exhaust gas exchange processes has been built and evaluated. The engine operates under its own power, but has a reduced power capacity than the conventional 2-valve engine. The reduction in power is traced to higher than expected amounts of exhaust gases flowing back into the intake system. Design changes to the cylinder head will fix the back flow problems, but the future capacity of mono-valve engine technology cannot be estimated. The back flow of exhaust gases increases the exhaust gas recirculation (EGR) rate and deteriorates combustion. Intake pressure data shows the mono-valve engine requires an advanced intake valve closing (IVC) time to prevent back flow of charge air. A single actuation camshaft with advanced IVC was tested in the mono-valve engine, and was found to improve exhaust scavenging at TDC and nearly eliminated all charge air back flow at IVC. The optimum IVC timing is shown to be approximately 30 crank angle degrees after BDC. The mono-valve cylinder head utilizes a rotary valve positioned above the tappet valve. The open spaces inside the rotary valveand between the rotary valve and tappet valve represent a common volume that needs to be reduced in order to reduce the base EGR rate. Multiple rotary valve configurations were tested, and the size of the common volume was found to have no effect on back flow but a direct effect on the EGR rate and engine performance. The position of the rotary valve with respect to crank angle has a direct effect on the scavenging process. Optimum scavenging occurs when the intake port is opened just after TDC.

  1. Age of the Mono Lake excursion and associated tephra

    Science.gov (United States)

    Benson, L.; Liddicoat, J.; Smoot, J.; Sarna-Wojcicki, A.; Negrini, R.; Lund, S.

    2003-01-01

    The Mono Lake excursion (MLE) is an important time marker that has been found in lake and marine sediments across much of the Northern Hemisphere. Dating of this event at its type locality, the Mono Basin of California, has yielded controversial results with the most recent effort concluding that the MLE may actually be the Laschamp excursion (Earth Planet. Sci. Lett. 197 (2002) 151). We show that a volcanic tephra (Ash #15) that occurs near the midpoint of the MLE has a date (not corrected for reservoir effect) of 28,620 ?? 300 14C yr BP (??? 32,400 GISP2 yr BP) in the Pyramid Lake Basin of Nevada. Given the location of Ash #15 and the duration of the MLE in the Mono Basin, the event occurred between 31,500 and 33,300 GISP2 yr BP, an age range consistent with the position and age of the uppermost of two paleointensity minima in the NAPIS-75 stack that has been associated with the MLE (Philos. Trans. R. Soc. London Ser. A 358 (2000) 1009). The lower paleointensity minimum in the NAPIS-75 stack is considered to be the Laschamp excursion (Philos. Trans. R. Soc. London Ser. A 358 (2000) 1009).

  2. Mono- versus polydrug abuse patterns among publicly funded clients

    Directory of Open Access Journals (Sweden)

    Relyea George

    2007-11-01

    Full Text Available Abstract To examine patterns of mono- versus polydrug abuse, data were obtained from intake records of 69,891 admissions to publicly funded treatment programs in Tennessee between 1998 and 2004. While descriptive statistics were employed to report frequency and patterns of mono- and polydrug abuse by demographic variables and by study years, bivariate logistic regression was applied to assess the probability of being a mono- or polydrug abuser for a number of demographic variables. The researchers found that during the study period 51.3% of admissions reported monodrug abuse and 48.7% reported polydrug abuse. Alcohol, cocaine, and marijuana were the most commonly abused substances, both alone and in combination. Odds ratio favored polydrug abuse for all but one drug category–other drugs. Gender did not affect drug abuse patterns; however, admissions for African Americans and those living in urban areas exhibited higher probabilities of polydrug abuse. Age group also appeared to affect drug abuse patterns, with higher odds of monodrug abuse among minors and adults over 45 years old. The discernable prevalence of polydrug abuse suggests a need for developing effective prevention strategies and treatment plans specific to polydrug abuse.

  3. Diameter Preserving Surjection on Alternate Matrices

    Institute of Scientific and Technical Information of China (English)

    Li Ping HUANG

    2009-01-01

    Let F be a field with |F| ≥ 3, Km be the set of all m × m (m ≥ 4) alternate matrices over F. The arithmetic distance of A, B ∈ Km is d(A, B) := rank(A- B). If d(A, B) = 2, then A and B are said to be adjacent. The diameter of Km is max{d(A, B) : A, B ∈ Km}. Assume that ψ : Km→ Km is a map. We prove the following are equivalent: (a) ψ is a diameter preserving surjection in both directions, (b) ψ is both an adjacency preserving surjection and a diameter preserving map, (c) ψ is a bijective map which preserves the arithmetic distance.

  4. Seismic monitoring of hydraulic fracturing: techniques for determining fluid flow paths and state of stress away from a wellbore

    Energy Technology Data Exchange (ETDEWEB)

    Fehler, M.; House, L.; Kaieda, H.

    1986-01-01

    Hydraulic fracturing has gained in popularity in recent years as a way to determine the orientations and magnitudes of tectonic stresses. By augmenting conventional hydraulic fracturing measurements with detection and mapping of the microearthquakes induced by fracturing, we can supplement and idependently confirm information obtained from conventional analysis. Important information obtained from seismic monitoring includes: the state of stress of the rock, orientation and spacing of the major joint sets, and measurements of rock elastic parameters at locations distant from the wellbore. While conventional well logging operations can provide information about several of these parameters, the zone of interrogation is usually limited to the immediate proximity of the borehole. The seismic waveforms of the microearthquakes contain a wealth of information about the rock in regions that are otherwise inaccessible for study. By reliably locating the hypocenters of many microearthquakes, we have inferred the joint patterns in the rock. We observed that microearthquake locations do not define a simple, thin, planar distribution, that the fault plane solutions are consistent with shear slippage, and that spectral analysis indicates that the source dimensions and slip along the faults are small. Hence we believe that the microearthquakes result from slip along preexisting joints, and not from tensile extension at the tip of the fracture. Orientations of the principal stresses can be estimated by using fault plane solutions of the larger microearthquakes. By using a joint earthquake location scheme, and/or calibrations with downhole detonators, rock velocities and heterogeneities thereof can be investigated in rock volumes that are far enough from the borehole to be representative of intrincis rock properties.

  5. The truth about small-diameter implants.

    Science.gov (United States)

    Christensen, Gordon J; Child, Paul L

    2010-05-01

    SDIs that are treatment planned correctly, placed and loaded properly, and are within a well-adjusted occlusion, are working in an excellent manner for the patients described in this article. It is time for those practitioners unfamiliar with SDIs and their uses to discontinue their discouragement of this technique. SDIs are easily placed, minimally invasive, and a true service to those patients described. They do not replace conventional diameter implants; however, they are a significant and important augmentation to the original root-form implant concept. There is obvious evidence of the growing acceptance of small-diameter implants by both general practitioners and specialists.

  6. THERMAL EVALUATION OF DIFFERENT DRIFT DIAMETER SIZES

    Energy Technology Data Exchange (ETDEWEB)

    H.M. Wade

    1999-01-04

    The purpose of this calculation is to estimate the thermal response of a repository-emplaced waste package and its corresponding drift wall surface temperature with different drift diameters. The case examined is that of a 21 pressurized water reactor (PWR) uncanistered fuel (UCF) waste package loaded with design basis spent nuclear fuel assemblies. This calculation evaluates a 3.5 meter to 6.5 meter drift diameter range in increments of 1.0 meters. The time-dependent temperatures of interest, as determined by this calculation, are the spent nuclear fuel cladding temperature, the waste package surface temperature, and the drift wall surface temperature.

  7. Shaft Diameter Measurement Using Structured Light Vision.

    Science.gov (United States)

    Liu, Siyuan; Tan, Qingchang; Zhang, Yachao

    2015-08-12

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  8. Shaft Diameter Measurement Using Structured Light Vision

    Directory of Open Access Journals (Sweden)

    Siyuan Liu

    2015-08-01

    Full Text Available A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  9. Influence of tube's diameter on boiling heat transfer performance in small diameter tubes

    Science.gov (United States)

    Gan, Chengjun; Wang, Weicheng; Zhang, Lining

    1998-03-01

    This paper reports the experiments of evaporation study in 6 mm inner copper diameter tubes using HFC-134a, HCFC-22 and CFC-12 as working fluid. The results show that the evaporation heat transfer coefficient increases with the decreasing of inner diameter of tubes. A new concept of non-dimensional tube diameter U is proposed in this paper for correction of the influence of the tube diameter on the evaporation heat transfer coefficient. And further, a convenient empirical correction method is presented.

  10. Influence of Tube‘s Diameter on Boling Heat Transfer Performance in Small Diameter Tubes

    Institute of Scientific and Technical Information of China (English)

    GanChengjun; WangWeicheng; 等

    1998-01-01

    This paper reports the experiments of evaporation study in 6 mm inner copper diameter tubes using HFC-134a,HCFC-22 and CFC-12 as working fluid.The results show that the evaporation heat transfer cofeeicient increasese with the decreasing of inner diameter of tubes,A new concept of nondimensional tube diameter U is proposed in this paper for correction of the influence of the tube diameter on the evaporation heat transfer coefficient.And further,a conveinent empirical correction method is preseted.

  11. Genetic structure and hierarchical population divergence history of Acer mono var. mono in South and Northeast China.

    Directory of Open Access Journals (Sweden)

    Chunping Liu

    Full Text Available Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE, whereas it has a scattered and patchy distribution in South China (SC. In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM. Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species' evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST  = 0.073; G'ST  = 0.278 among all populations, but significantly higher in the SC group than the NE group, mirroring the species' more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

  12. Genetic structure and hierarchical population divergence history of Acer mono var. mono in South and Northeast China.

    Science.gov (United States)

    Liu, Chunping; Tsuda, Yoshiaki; Shen, Hailong; Hu, Lijiang; Saito, Yoko; Ide, Yuji

    2014-01-01

    Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE), whereas it has a scattered and patchy distribution in South China (SC). In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM). Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species' evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST  = 0.073; G'ST  = 0.278) among all populations, but significantly higher in the SC group than the NE group, mirroring the species' more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

  13. Gamma spectra pictures using a digital plotter. Program MONO; Representacion de Espectros directos mediante un trazado digital. Prograa MONO

    Energy Technology Data Exchange (ETDEWEB)

    Los Arcos, J. M.

    1978-07-01

    The program MONO has been written for a CALCOMP-936 digital plotter operating off- -line with a UMI VAC 1106 computer, to obtain graphic representations of single gamma spectra stored on magnetic tape. It allows to plot the whole spectrum or only a part, as well as to draw a given spectrum on the same or different picture than the previous one. Ten representation scales are available and at up nine comment lines can be written in a graphic. (Author) 4 refs.

  14. The relationship between mono-abundance and mono-age stellar populations in the Milky Way disk

    CERN Document Server

    Minchev, I; Chiappini, C; Martig, M; Anders, F; Matijevic, G; de Jong, R S

    2016-01-01

    Studying the Milky Way disk structure using stars in narrow bins of [Fe/H] and [alpha/Fe] has recently been proposed as a powerful method to understand the Galactic thick and thin disk formation. It has been assumed so far that these mono-abundance populations (MAPs) are also coeval, or mono-age, populations. Here we study this relationship for a Milky Way chemo-dynamical model and show that equivalence between MAPs and mono-age populations exists only for the high-[alpha/Fe] tail, where the chemical evolution curves of different Galactic radii are far apart. At lower [alpha/Fe]-values a MAP is composed of stars with a range in ages, even for small observational uncertainties and a small MAP bin size. Due to the disk inside-out formation, for these MAPs younger stars are typically located at larger radii, which results in negative radial age gradients that can be as large as 2 Gyr/kpc. Positive radial age gradients can result for MAPs at the lowest [alpha/Fe] and highest [Fe/H] end. Such variations with age p...

  15. Groundwater-Quality Impacts from Natural-Gas Wellbore Leakage: Numerical Sensitivity Analysis of Hydrogeologic, Geostatistical, and Source-Term Parameterization at Varying Depths

    Science.gov (United States)

    Rice, A. K.; McCray, J. E.; Singha, K.

    2016-12-01

    The development of directional drilling and stimulation of reservoirs by hydraulic fracturing has transformed the energy landscape in the U.S. by making recovery of hydrocarbons from shale formations not only possible but economically viable. Activities associated with hydraulic fracturing present a set of water-quality challenges, including the potential for impaired groundwater quality. In this project, we use a three-dimensional, multiphase, multicomponent numerical model to investigate hydrogeologic conditions that could lead to groundwater contamination from natural gas wellbore leakage. This work explores the fate of methane that enters a well annulus, possibly from an intermediate formation or from the production zone via a flawed cement seal, and leaves the annulus at one of two depths: at the elevation of groundwater or below a freshwater aquifer. The latter leakage scenario is largely ignored in the current scientific literature, where focus has been on leakage directly into freshwater aquifers, despite modern regulations requiring steel casings and cement sheaths at these depths. We perform a three-stage sensitivity analysis, examining (1) hydrogeologic parameters of media surrounding a methane leakage source zone, (2) geostatistical variations in intrinsic permeability, and (3) methane source zone pressurization. Results indicate that in all cases methane reaches groundwater within the first year of leakage. To our knowledge, this is the first study to consider natural gas wellbore leakage in the context of multiphase flow through heterogeneous permeable media; advantages of multiphase modeling include more realistic analysis of methane vapor-phase relative permeability as compared to single-phase models. These results can be used to inform assessment of aquifer vulnerability to hydrocarbon wellbore leakage at varying depths.

  16. PREDICTING METHOD OF THE WELLBORE STABILITY OF INCLINED WELL BY WELL LOGGING%斜井井壁稳定的测井预测方法

    Institute of Scientific and Technical Information of China (English)

    陈科贵; 夏亚良; 高成军; 张歧安

    2011-01-01

    从影响井壁稳定的力学因素出发,通过井壁围岩应力分析提取影响斜井井壁稳定的主应力,结合岩石破坏的强度准则建立地层坍塌压力和破裂压力的测井预测模型.针对研究工区地质情况对模型进行适当修正,建立了该区安全钻井液密度窗口.通过精细解释测井资料预测的井壁稳定情况表明,测井资料能够较好地预测井壁的稳定性,为防止井漏、井塌等工程事故提供了重要依据.%Starting from the mechanic factors that influence wellbore stability, the main stress that influences well stability of inclined well is determined through borehole wall surrounding rock stress analysis, and combining with the intensity principle of rock damage, logging prediction model of formation caving pressure and fracture pressure is established. Certain modification is made to the model considering the geological conditions of the studied area, and density window of safe drilling fluid is established. The wellbore stability predicted by the fine interpretation of logging data shows that logging data can predict wellbore stability and provide criteria for the prevention of engineering accident, such as circulation loss, hole collapse, etc.

  17. Numerical Analysis of Large Diameter Butterfly Valve

    Science.gov (United States)

    Youngchul, Park; Xueguan, Song

    In this paper, a butterfly valve with the diameter of 1,800 mm was studied. Three-dimensional numerical technique by using commercial code CFX were conducted to observe the flow patterns and to measure flow coefficient, hydrodynamic torque coefficient and so on, when the large butterfly valve operated with various angles and uniform incoming velocity.

  18. Photoacoustic determination of blood vessel diameter.

    NARCIS (Netherlands)

    Kolkman, R.G.; Klaessens, J.H.G.M.; Hondebrink, E.; Hopman, J.C.W.; Mul, F.F. de; Steenbergen, W.; Thijssen, J.M.; Leeuwen, T.G. van

    2004-01-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (tau(pp)) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual ves

  19. Reduced artery diameters in Klinefelter syndrome.

    Science.gov (United States)

    Foresta, C; Caretta, N; Palego, P; Ferlin, A; Zuccarello, D; Lenzi, A; Selice, R

    2012-10-01

    Various epidemiological studies in relatively large cohorts of patients with Klinefelter syndrome (KS) described the increased morbidity and mortality in these subjects. Our aim was to study the structure and function of arteries in different districts to investigate in these subjects possible alterations. A total of 92 patients having non-mosaic KS, diagnosed in Centre for Human Reproduction Pathology at the University of Padova, and 50 age-matched healthy male controls were studied. Klinefelter syndrome subjects and controls evaluation included complete medical history, physical examination, measurement of concentrations of the reproductive hormones, lipidic and glycidic metabolism, AR function and sensitivity, ultrasound examinations (diameters, carotid intima-media thickness and brachial flow-mediated dilation) of brachial, common carotid and common femoral artery and abdominal aorta. Klinefelter syndrome patients showed significantly reduced artery diameters in all districts evaluated. On the contrary no statistically significant difference was found in cIMT and brachial FMD values between KS patients and controls. Furthermore, we found no statistically significant correlation of artery diameters with reproductive hormones, metabolic parameters, anthropometric measures and weighted CAG repeats. To our knowledge, this is the first study finding a reduced artery diameter in several districts in KS patients compared with that of normal male subjects and overlapping to that of female subjects. We have not an explanation for this phenomenon, even if a possible involvement of genes controlling the development of vascular system might be hypothesized, and further research is required to verify this hypothesis.

  20. Empirical processes with bounded \\psi_1 diameter

    CERN Document Server

    Mendelson, Shahar

    2010-01-01

    We study the empirical process indexed by F^2=\\{f^2 : f \\in F\\}, where F is a class of mean-zero functions on a probability space. We present a sharp bound on the supremum of that process which depends on the \\psi_1 diameter of the class F (rather than on the \\psi_2 one) and on the complexity parameter \\gamma_2(F,\\psi_2). In addition, we present optimal bounds on the random diameters \\sup_{f \\in F} \\max_{|I|=m} (\\sum_{i \\in I} f^2(X_i))^{1/2} using the same parameters. As applications, we extend several well known results in Asymptotic Geometric Analysis to any isotropic, log-concave ensemble on R^n.

  1. Transfinite diameter of Bernstein sets in

    Directory of Open Access Journals (Sweden)

    Bialas-Cież Leokadia

    2002-01-01

    Full Text Available Let be a compact set in satisfying the following generalized Bernstein inequality: for each such that , for each polynomial of degree where is a constant independent of and , is an infinite set of natural numbers that is also independent of and . We give an estimate for the transfinite diameter of the set : For satisfying the usual Bernstein inequality (i.e., , we prove that

  2. iOS Development using MonoTouch Cookbook

    CERN Document Server

    Tavlikos, Dimitris

    2011-01-01

    The book is written in a cookbook style, presenting examples in the style of recipes, allowing you to go directly to your topic of interest, or follow topics throughout a chapter to gain in-depth knowledge. This book is essential for C# and .NET developers with no previous experience in iOS development and Objective-C developers that want to make a transition to the benefits of MonoTouch and the C# language, for creating complete, compelling iPhone, iPod and iPad applications and deploying them to the App Store.

  3. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl ...

    Science.gov (United States)

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from other Federal agencies and White House Offices are provided below with external peer review panel comments. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of EGBE that will appear on the Integrated Risk Information System (IRIS) database.

  4. New Large Diameter RF Complex Plasma Device

    Science.gov (United States)

    Meyer, John; Nosenko, Volodymyr; Thomas, Hubertus

    2016-10-01

    The Complex Plasma Research Group at the German Aerospace Center (DLR) in Oberpfaffenhofen has built a new large diameter rf plasma setup for dusty plasma experiments. The vacuum chamber is a stainless steel cylinder 0.90 m in diameter and 0.34 m in height with ports for viewing and measurement. A 0.85 m diameter plate in about the center serves as a powered electrode (13.56 MHz) with the chamber walls as the ground. It is pumped on by one of two Oerlikon turbo pumps with a pumping rate of 1100 l/s or 270 l/s. Argon gas is admitted into the chamber by an MKS mass flow meter and pumping is regulated by a butterfly valve to set pressure for experiments. A manual dropper is used to insert dust into the plasma. The dust is illuminated horizontally by a 660 nm 100 mW laser sheet and viewed from above by a Photron FASTCAM 1024 PCI camera. A vertical laser sheet of 635 nm will be used for side imaging. So far, single-layer plasma crystals of up to 15000 particles have been suspended. The particle velocity fluctuation spectra were measured and from these, the particle charge and screening length were calculated. Future experiments will explore the system-size dependence of the plasma crystal properties.

  5. 29 mm Diameter Test Target Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-15

    The Northstar target for Mo99 production is made up of Mo100 disks in a stack separated by coolant gaps for helium flow. A number of targets have been tested at ANL for both production of Mo99 and for thermal-hydraulic performance. These have all been with a 12 mm diameter target, even while the production goals have increased the diameter to now 29 mm. A 29 mm diameter target has been designed that is consistent with the ANL beam capabilities and the capabilities of the helium circulation system currently in use at ANL. This target is designed for 500 μA at 35 MeV electrons. While the plant design calls for 42 MeV, the chosen design point is more favorable and higher power given the limits of the ANL accelerator. The intended beam spot size is 12 mm FWHM, but the thermal analysis presented herein conservatively assumed a 10 mm FWHM beam, which results in a 44% higher beam current density at beam center.

  6. Determining the mechanical strength of CO2-induced reaction zones in wellbore cement: is it worth it?

    Science.gov (United States)

    Hangx, Suzanne; Marcelis, Fons; van der Linden, Arjan; Liteanu, Emilia

    2015-04-01

    CO2 injection, either for long-term CO2 storage (CCS) or Enhanced Oil Recovery (EOR), strongly hinges on maintaining storage integrity. Injection and legacy wells penetrating the caprock pose one of the most likely points of leakage. In order to be able to predict the long-term integrity of such wellbores, it's important to understand their chemical, hydrological and mechanical behaviour, and how it may change due to CO2 exposure. Generally, in response to CO2/brine/cement interactions, a number of different reaction zones are observed, each with their own chemical, and hence mechanical, signature. To aid mechanical modelling efforts, assessing the risk of cement failure caused by stress and temperature changes, knowledge is required of the strength of each of these zones. We performed experiments on Class G Portland cement to investigate the chemical-mechanical coupling due to CO2-exposure. Batch reaction experiments, in the presence of CO2-rich brine, were performed under typical storage conditions (T = 65° C, PCO2 = 8 MPa) for various periods of time (1, 2, 3, 4, 5 and 6 months). After exposure, mechanical tests were performed on the observed reaction zones, using the so-called core scratching technique, to evaluate the unconfined compressive strength (UCS) as a function of exposure time. Chemical analyses (CT-imaging, SEM microscopy, EDX chemical analysis) showed the formation of three reaction zones, similarly to what has been observed in other studies. Measurements of the mechanical strength of these different zones showed highly variable results. Such variations have also been observed in other studies, using different measurement techniques. The large variability in strength measurements is most likely an inherent result of the heterogenic nature of cement, which affects the extent and location of reaction throughout the sample. This begs the question: is it worth studying the mechanical strength of reaction-induced zones in cement? Or will it suffice to

  7. Micro-magnetic simulation study on the magnetic particle imaging performance of anisotropic mono-domain particles.

    Science.gov (United States)

    Weizenecker, Jürgen; Gleich, Bernhard; Rahmer, Jürgen; Borgert, Jörn

    2012-11-21

    The performance of magnetic mono-domain particles is of crucial importance in magnetic particle imaging (MPI). So far, the behavior of mono-domain particles has been modeled within the framework of Langevin theory. This theory predicts the dependence of the MPI signal on the particle core size, but cannot account for the influence of the shape, i.e. the anisotropy of the particle core. In this study we present the first micro-magnetic ab initio simulation of spectra of anisotropic particles with different core diameters in an oscillating magnetic field at 25 and 100 kHz. We find that the MPI signal strongly depends on the anisotropy of the magnetic core. Thus, a difference of 3 nm between the principal axes of a prolate ellipsoid with the volume of a 30 nm sphere can result in a complete loss of the MPI signal. Smaller anisotropies, however, can increase the MPI performance of the particle. The simulations show that the effect of the anisotropy on the MPI signal depends on the frequency of the oscillating magnetic field. At 100 kHz, the optimal signal is found at smaller anisotropies than at 25 kHz. Furthermore, the simulations show that experimental spectroscopic results for Resovist® can only be explained quantitatively by particles with a magnetic core size of at least 25 nm.

  8. Electro-spray of high viscous liquids for producing mono-sized spherical alginate beads

    Institute of Scientific and Technical Information of China (English)

    Hamid Moghadam; Mohsen Samimi; Abdolreza Samimi; Mohamad Khorram

    2008-01-01

    Alginate beads, often used for controlled release of enzymes and drugs, are usually produced by spraying sodium alginate liquid into a gelling agent using mechanical vibration nozzle or air jet. In this work an alternative method of electro-spray was employed to form droplets with desired size from a highly viscous sodium alginate solution using constant DC voltage. The droplets were then cured in a calcium chloride solution. The main objective was to produce mono-sized beads from such a highly viscous and non-Newtonian liquid (1000-5000 mPa s). The effects of nozzle diameter, flow rate and concentration of liquid on the size of the beads were investigated. Among the parameters studied, voltage had a pronounced effect on the size of beads as compared to flow rate zzle diameter and concentration of alginate liquid. The size of beads was reduced to a minimum value with increasing the voltage in the range of 0-10 kV. At the early stages of voltage increase (I.e. Up to about 4 kV), the rate of size reduction was relatively low, while the dripping mode dominated. However, in the middle part of the range of applied voltage, where the rate of size reduction was high (I.e. About 4-7 kV), an unstable transition occurred between dripping and jetting. At the end part of the range (I.e. 7-10 kV) jet mode of spray was observed. Increasing the height of fall of the droplets was found to improve the sphericity of the beads, because of the increased time of flight for the droplets. This was especially identifiable at higher concentrations of the alginate liquid (I.e. 3 w/v%)

  9. Mono-Energy Coronary Angiography with a Compact Synchrotron Source

    Science.gov (United States)

    Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noёl, Peter B.; Pfeiffer, Franz; Muenzel, Daniela

    2017-02-01

    X-ray coronary angiography is an invaluable tool for the diagnosis of coronary artery disease. However, the use of iodine-based contrast media can be contraindicated for patients who present with chronic renal insufficiency or with severe iodine allergy. These patients could benefit from a reduced contrast agent concentration, possibly achieved through application of a mono-energetic x-ray beam. While large-scale synchrotrons are impractical for daily clinical use, the technology of compact synchrotron sources strongly advanced during the last decade. Here we present a quantitative analysis of the benefits a compact synchrotron source can offer in coronary angiography. Simulated projection data from quasi-mono-energetic and conventional x-ray tube spectra is used for a CNR comparison. Results show that compact synchrotron spectra would allow for a significant reduction of contrast media. Experimentally, we demonstrate the feasibility of coronary angiography at the Munich Compact Light Source, the first commercial installation of a compact synchrotron source.

  10. Crustal structure between Lake Mead, Nevada, and Mono Lake, California

    Science.gov (United States)

    Johnson, Lane R.

    1964-01-01

    Interpretation of a reversed seismic-refraction profile between Lake Mead, Nevada, and Mono Lake, California, indicates velocities of 6.15 km/sec for the upper layer of the crust, 7.10 km/sec for an intermediate layer, and 7.80 km/sec for the uppermost mantle. Phases interpreted to be reflections from the top of the intermediate layer and the Mohorovicic discontinuity were used with the refraction data to calculate depths. The depth to the Moho increases from about 30 km near Lake Mead to about 40 km near Mono Lake. Variations in arrival times provide evidence for fairly sharp flexures in the Moho. Offsets in the Moho of 4 km at one point and 2 1/2 km at another correspond to large faults at the surface, and it is suggested that fracture zones in the upper crust may displace the Moho and extend into the upper mantle. The phase P appears to be an extension of the reflection from the top of the intermediate layer beyond the critical angle. Bouguer gravity, computed for the seismic model of the crust, is in good agreement with the measured Bouguer gravity. Thus a model of the crustal structure is presented which is consistent with three semi-independent sources of geophysical data: seismic-refraction, seismic-reflection, and gravity.

  11. Mono(ADP-ribosylation) in rat liver mitochondria.

    Science.gov (United States)

    Frei, B; Richter, C

    1988-01-26

    This paper investigates protein mono(ADP-ribosylation) in rat liver mitochondria. In isolated inner mitochondrial membranes, in the presence of both ADP-ribose and NAD+, a protein is mono-(ADP-ribosylated) with high specificity. The reaction apparently consists of enzymatic NAD+ glycohydrolysis and subsequent binding of free ADP-ribose to the acceptor protein. In terms of chemical stability, the resulting bond is unique among the ADP-ribose linkages thus far characterized. Formation of a Schiff base adduct between free ADP-ribose and the acceptor protein is excluded. In intact mitochondria at least three classes of proteins are ADP-ribosylated in vivo. One ADP-ribose-protein linkage is of the carboxylate ester type as indicated by its lability in neutral buffer. Another class of ADP-ribosylated proteins requires hydroxylamine for release of ADP-ribose. The third class is stable in hydroxylamine but labile to alkali, similar to the ADP-ribose-cysteine linkage in transducin formed by pertussis toxin.

  12. Leptonic mono-top from single stop production at LHC

    CERN Document Server

    Duan, Guang Hua; Wu, Lei; Yang, Jin Min; Zhang, Mengchao

    2016-01-01

    Top squark (stop) can be produced via QCD interaction but also the electroweak interaction at the LHC. In this paper, we investigate the observability of the associated production of stop and chargino, $pp \\to \\tilde{t}_1\\tilde{\\chi}^-_1$, in compressed electroweakino scenario at the 14 TeV LHC. Due to the small mass-splitting between the lightest neutralino ($\\tilde{\\chi}^0_1$) and chargino ($\\tilde{\\chi}^-_1$), such a single stop production can give a mono-top signature through the stop decay $\\tilde{t}_1 \\to t \\tilde{\\chi}^0_1$. Focusing on the leptonic mono-top channel, we propose a lab-frame observable $\\cos\\theta_{b\\ell}$ to reduce the SM backgrounds in virtue of a boosted top quark from the stop decay. We find that the single stop production can be probed at $2\\sigma$ level at the HL-LHC for $m_{\\tilde{t}_1}<760$ GeV and $m_{\\tilde{\\chi}^0_1}<150$ GeV.

  13. Mono-W Dark Matter Signals at the LHC: Simplified Model Analysis

    CERN Document Server

    Bell, Nicole F; Leane, Rebecca K

    2015-01-01

    We study mono-W signals of dark matter (DM) production at the LHC, in the context of gauge invariant renormalizable models. We analyze two simplified models, one involving an s-channel Z' mediator and the other a t-channel colored scalar mediator, and consider examples in which the DM-quark couplings are either isospin conserving or isospin violating after electroweak symmetry breaking. While previous work on mono-W signals have focused on isospin violating EFTs, obtaining very strong limits, we find that isospin violating effects are small once such physics is embedded into a gauge invariant simplified model. We thus find that the 8 TeV mono-W results are much less constraining than those arising from mono-jet searches. Considering both the leptonic (mono-lepton) and hadronic (mono fat jet) decays of the W, we determine the 14 TeV LHC reach of the mono-W searches with 3000 fb$^{-1}$ of data. While a mono-W signal would provide an important complement to a mono-jet discovery channel, existing constraints on t...

  14. Finned Small Diameter Tube Heat Exchanger

    Science.gov (United States)

    Dang, Chaobin; Daiguji, Hirofumi; Hihara, Eiji; Tokunaga, Masahide

    The performance of fined small tube heat exchangers was investigated both experimentally and theoretically. The Inner diameters of tubes were 1.0mm, 2.1mm and 4.0mm. Exchanged heat and pressure drop obtained from numerical simulation agreed well with the experimental ones. Calculation results show that the volume of a 2.0mm tube heat exchanger can be reduced to 33% of that of a 4mm tube heat exchanger with the same capacity. In addition the distribution of two-phase flow in a branching unit was investigated by measuring downstream temperature distribution. The flow distribution in a branching unit strongly affects the exchanged heat.

  15. Retrobulbar diameter of optic nerve in glaucoma

    Directory of Open Access Journals (Sweden)

    Stefanović Ivan

    2009-01-01

    Full Text Available Introduction. The ultrasound diagnostics of the optic nerve includes the analysis of the optic nerve disc (PNO and measuring of its retrobulbar diameter. With B-scan, by Schraeder's method, it is possible to measure very precisely the optic nerve, the pial diameter, the normal values for the pial diameter being 2.8-4.1 mm. In glaucoma, the disease that is most frequently associated with higher intraocular pressure, there comes the destruction of nerve fibres, which can be visualized as the excavation of the optic nerve disc. Objective. In this paper, we were interested in finding whether in glaucoma, and in what phase of the disease, the optic nerve starts growing thinner. Aware of many forms of this very complex disease, we were interested in knowing if the visualization of excavation on the optic nerve disc is related to diminishing of the pial diameter of the retrobulbar nerve part. Methods. There were treated the patients who had already had the diagnosis of glaucoma and the visualized excavation of the optic disc of various dimensions. Echographically, there was measured the thickness of the retrobulbar part of the optic nerve and the finding compared in relation to the excavation of the optic disc. Results. In all eyes with glaucoma, a normal size of the retrobulbar part of the optic nerve was measured, ranging from 3.01 to 3.91 mm with the median of 3.36 mm. Also, by testing the correlation between the thickness of the optic nerve and the excavation of the PNO, by Pearson test, we found that there was no correlation between these two parameters (r=0.109; p>0.05. Conclusion. In the patients with glaucoma, the retrobulbar part of the optic nerve is not thinner (it has normal values, even not in the cases with a totally excavated optic disc. There is no connection between the size of the PNO excavation and the thickness of the retrobulbar part of the optic nerve.

  16. Measurement of Diameter Changes during Irradiation Testing

    Energy Technology Data Exchange (ETDEWEB)

    Davis, K. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Knudson, D. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Crepeau, J. C. [Univ. of Idaho, Idaho Falls, ID (United States); Solstad, S. [Inst. for Energy Technologoy, Halden (Norway)

    2015-03-01

    New materials are being considered for fuel, cladding, and structures in advanced and existing nuclear reactors. Such materials can experience significant dimensional and physical changes during irradiation. Currently in the US, such changes are measured by repeatedly irradiating a specimen for a specified period of time and then removing it from the reactor for evaluation. The time and labor to remove, examine, and return irradiated samples for each measurement makes this approach very expensive. In addition, such techniques provide limited data and handling may disturb the phenomena of interest. In-pile detection of changes in geometry is sorely needed to understand real-time behavior during irradiation testing of fuels and materials in high flux US Material and Test Reactors (MTRs). This paper presents development results of an advanced Linear Variable Differential Transformer-based test rig capable of detecting real-time changes in diameter of fuel rods or material samples during irradiation in US MTRs. This test rig is being developed at the Idaho National Laboratory and will provide experimenters with a unique capability to measure diameter changes associated with fuel and cladding swelling, pellet-clad interaction, and crud buildup.

  17. Sagittal Abdominal Diameter: Application in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Thaís Da Silva-Ferreira

    2014-05-01

    Full Text Available Excess visceral fat is associated with cardiovascular risk factors. Sagittal abdominal diameter (SAD has recently been highlighted as an indicator of abdominal obesity, and also may be useful in predicting cardiovascular risk. The purpose of the present study was to review the scientific literature on the use of SAD in adult nutritional assessment. A search was conducted for scientific articles in the following electronic databases: SciELO , MEDLINE (PubMed and Virtual Health Library. SAD is more associated with abdominal fat (especially visceral, and with different cardiovascular risk factors, such as, insulin resistance, blood pressure, and serum lipoproteins than the traditional methods of estimating adiposity, such as body mass index and waist-to-hip ratio. SAD can also be used in association with other anthropometric measures. There are still no cut-off limits established to classify SAD as yet. SAD can be an alternative measure to estimate visceral adiposity. However, the few studies on this diameter, and the lack of consensus on the anatomical site to measure SAD, are obstacles to establish cut-off limits to classify it.

  18. A wellbore flow model of CO2 separate injection with concentric dual tubes and its affecting factors%同心双管分注CO2井筒流动模型及影响因素

    Institute of Scientific and Technical Information of China (English)

    吴晗; 吴晓东; 王庆; 朱明; 方越

    2011-01-01

    In view of issues of the low efficiency and poor effect in the process of commingled CO2 injection, a CO2 separate injection with concentric dual tubes was proposed. On the basis of the heat transfer principle and fluid flow theory, a mathematical model considering CO2 phase change as flowing along the wellbore of concentric dual tubes and heat transfer was established, with which temperature and pressure distributions of CO2 along the annulus between inner and outer tubes and in the inner tubing string were calculated. Moreover, effects brought about by various factors, such as injection rate, injection temperature, injection pressure, assemblage of inner and outer tubes, interval of injection layers etc. , on the pressure and temperature of CO2 flowing both in the annulus between inner and outer tubes and in the inner tubing string were investigated as well. The results indicate that on condition that wellhead injection parameters of inner and outer tubes are the same, the bigger the diameter of the outer tube, the higher the temperature of the annulus between inner and outer tubes. If the diameter of the outer tube keeps constant, the pressure of the annulus will increase with decreasing the diameter of the inner tube that has a small influence on the temperature of the annulus. When inner and outer tubes have definite diameters, the wellhead injection rate, injection temperature and intervals of injection layers may all have significant effects on temperature and pressure distributions of the annulus and the inner tube, while the wellhead injection pressure affects them a little.%针对CO2笼统注入过程中效率低、效果差等问题,提出了同心双管分注CO2技术.根据热量传递原理和流体流动理论,建立了考虑CO2相态变化的同心双管井筒流动与传热的数学模型,利用该模型研究了CO2沿内外管环空和内油管的温度和压力分布规律,分析了井口注入量、注入温度、注入压力、内外管

  19. Mono- and combined antimicrobial agents efficiency in experimental wound infection

    Directory of Open Access Journals (Sweden)

    Наталія Ігорівна Філімонова

    2015-10-01

    Full Text Available Modern problems of antibiotic therapy are shown by wide range of side effects, both on organism and microbiological levels: the spread of allergies, toxic for organ systems reactions, dysbiosis development, and resistant pathogens formation and dissemination. Therefore the necessity of search for new effective drugs with significant antimicrobial activity applied for the wounds treatment arises. Development of combined remedies on the background of different origin antimicrobial agents’ derivatives is one of the fight directions against infectious diseases in the skin pathology. Recently among the existing antimicrobial agents one should focus on antiseptic drugs, due to degenerative and dysfunctional effect on microbial cell.Aim of research. The comparison of mono- and combined antimicrobial agents chemotherapeutic efficiency in the treatment of localized purulent infection under experimental conditions.Metods. The study of chemotherapeutic efficiency was carried out on the model of localized purulent Staphylococcus infection on albino mice weighting 14 – 16 g. S.aureus ATCC 25923 strains were used as infectious agents. The contamination was performed subcutaneously to the right side of mice’s skin after depilation. The animals were randomly divided into 4 groups: the 1st group – infected mice without treatment (control; the 2nd group – infected mice treated with a ciprofloxacin; the 3rd group – infected mice treated with a Ciprofloxacin and Decamethoxin combination; the 4th group – infected mice treated with a combined drug on the base of mutual prodrugs (Hexamethylenetetramine and Phenyl salicylate.Results. The efficiency of mono- and combined antimicrobial agents under experimental Staphylococcus wound infection conditions was studied. It was found that localized purulent staph center was formed more slowly in comparison with control and mono preparation use (2nd group of animals. The average index of skin lesions in comparison

  20. AREA 2: Novel Materials for Robust Repair of Leaky Wellbores in CO2 Storage Formations

    Energy Technology Data Exchange (ETDEWEB)

    Balhoff, Matthew [Univ. of Texas, Austin, TX (United States); Tavassoli, Shayan [Univ. of Texas, Austin, TX (United States); Fei Ho, Jostine [Univ. of Texas, Austin, TX (United States)

    2016-01-31

    cement cores to remove calcium and prevent syneresis during polymer placement. A chelating agent, sodium triphosphate (Na5P3O10), was found to successfully eliminate syneresis without compromising the injectivity of polymer solution during placement. Polymer gel strength is determined by recording the maximum holdback pressure gradients during liquid breakthrough tests after various periods of pretreatment and polymer shut-in time. Cores pretreated with Na5P3O10 successfully held up to an average of 80 psi/ft, which is significantly greater than the expected threshold value of about 0.1-5 psi/ft required to prevent flow in a typical CO2 leakage scenario. The use of such inexpensive, pH-triggered poly-acrylic acid polymer allows long-term robust seal of leaky wellbores under high pH conditions.

  1. Iron and Sulfur Geochemistry in Class H Wellbore Cements Exposed to CO2 and H2S

    Science.gov (United States)

    Lopano, C. L.; Webb, S. M.; Kutchko, B. G.; Strazisar, B. R.; Hawthorne, S. B.; Miller, D. J.; Guthrie, G.; Hakala, A.

    2013-12-01

    The effects of CO2 & co-constituents (such as H2S) sequestration on cement seal integrity are not well understood in the context of wellbore integrity for CO2 storage. This study evaluates the redox effects that co-contaminants such as H2S present to the CO2-cement reaction system via synchrotron X-ray XANES mapping specific to the iron and sulfur edge energies. Portland Class H cement was exposed to various proportions of H2S:CO2 in 1% NaCl saturated brine (1%, 21 mol%, and 40% H2S) under supercritical conditions (50°C and 15MPa). The reaction of cement with H2S-CO2 results in the formation of pyrite associated with the Fe-rich cement clinker phase, brownmillerite (also termed ferrite). Ferrite has not reacted in previous exposures to CO2 alone, which was confirmed by synchrotron spectroscopic analysis of cement exposed to supercritical CO2 alone. Thus it is hypothesized that the reaction is a result of redox conditions introduced by H2S. The synchrotron X-ray microprobe fluorescence (μXRF) imaging and spectroscopy capabilities at beamlines 2-3 and 14-3 at SSRL were used to collect multiple energy (ME) maps for both Fe and S in order to evaluate reaction fronts in the cement matrix and to monitor the chemical changes in the cement associated with exposure to CO2 (and H2S) at sequestration conditions. The use of this micro-spectroscopy technique allows for in-situ identification of any reaction intermediates (including amorphous materials) for the Fe and S phases in the cement. The coupled μXANES and μXRF data were used to generate iron and S speciation maps of the cement cores. Synchrotron microprobe capabilities at 2-3 were used to collected ME maps of Fe, and show differences in Fe oxidation between the rims (Fe2+) and cores (Fe3+) of the cement thin section. Analysis of Fe XANES indicates that there are potentially 4+ distinct coordination environments for the Fe in the cement cores studied: pyrite, ferrihydrite, brownmillerite (Fe3+, and/or Fe2+) and

  2. Mono-jet signatures of gluphilic scalar dark matter

    Science.gov (United States)

    Godbole, Rohini M.; Mendiratta, Gaurav; Shivaji, Ambresh; Tait, Tim M. P.

    2017-09-01

    A gluphilic scalar dark matter (GSDM) model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum (;mono-jet;) in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT) treatment, and find (as expected) that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3) representation of the mediator) from the √{ s} = 8 TeV data, and show the expected reach of the √{ s} = 13 TeV LHC and a future 100 TeV pp collider to constrain or discover GSDM models.

  3. Aryl hydrocarbon mono-oxygenase activity in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, G.D.; Schuresko, D.D.

    1981-06-01

    Aryl hydrocarbon mono-oxygenase (AHM), an enzyme of key importance in metabolism of xenobiotic chemicals such as polynuclear aromatic hydrocarbons (PNA), is present in human lymphocytes. Studies investing the relation of activity of AHM in human lymphocytes to parameters such as disease state, PNA exposure, in vitro mitogen stimulation, etc. have been summarized in this report. Some studies have demonstrated increased AHM activity in lymphocytes from cigarette smokers (compared to nonsmokers), and in lung cancer patients when compared to appropriate control groups. These observations are confused by extreme variability in human lymphocyte AHM activities, such variability arising from factors such as genetic variation in AHM activity, variation in in vitro culture conditions which affect AHM activity, and the problematical relationship of common AHM assays to actual PNA metabolism taking place in lymphocytes. If some of the foregoing problems can be adequately addressed, lymphocyte AHM activity could hold the promise of being a useful biomarker system for human PNA exposure.

  4. Mono-jet Signatures of Gluphilic Scalar Dark Matter

    CERN Document Server

    Godbole, Rohini M; Shivaji, Ambresh; Tait, Tim M P

    2016-01-01

    A gluphilic scalar dark matter (GSDM) model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum ("mono-jet") in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT) treatment, and find (as expected) that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3) representation of the mediator) from the $\\sqrt{s}=$ 8 TeV data, and show the expected reach of the $\\sqrt{s}=$ 13 TeV LHC and a future 100 TeV $pp$ collider to constrain or discover GSDM models.

  5. Mechanically flexible optically transparent porous mono-crystalline silicon substrate

    KAUST Repository

    Rojas, Jhonathan Prieto

    2012-01-01

    For the first time, we present a simple process to fabricate a thin (≥5μm), mechanically flexible, optically transparent, porous mono-crystalline silicon substrate. Relying only on reactive ion etching steps, we are able to controllably peel off a thin layer of the original substrate. This scheme is cost favorable as it uses a low-cost silicon <100> wafer and furthermore it has the potential for recycling the remaining part of the wafer that otherwise would be lost and wasted during conventional back-grinding process. Due to its porosity, it shows see-through transparency and potential for flexible membrane applications, neural probing and such. Our process can offer flexible, transparent silicon from post high-thermal budget processed device wafer to retain the high performance electronics on flexible substrates. © 2012 IEEE.

  6. Mono-jet signatures of gluphilic scalar dark matter

    Directory of Open Access Journals (Sweden)

    Rohini M. Godbole

    2017-09-01

    Full Text Available A gluphilic scalar dark matter (GSDM model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum (“mono-jet” in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT treatment, and find (as expected that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3 representation of the mediator from the s=8 TeV data, and show the expected reach of the s=13 TeV LHC and a future 100 TeV pp collider to constrain or discover GSDM models.

  7. Fire protection covering for small diameter missiles

    Science.gov (United States)

    Riccitiello, S. R.; Sawko, P. M. (Inventor)

    1979-01-01

    Flexible intumescent protection sheeting of unusually uniform thickness were prepared from epoxy-polysulfide compositions, containing microfibers and the ammonium salt of 1,4-nitroaniline-2-sulfonic acid, as disclosed in U.S. Pat. No. 3,663,464, except that an ammonium salt particle size in the order of 5 to 8 microns and a fiber size of about 1/128th inch in length and 3 to 5 microns in diameter were found critical to obtain the required density of 1.46 to 1.50 g/cc. The insulation sheeting was prepared by a continuous process involving vacuum mixing, calendering, and curing under very strict conditions which depend to some extent upon the thickness of the sheet produced.

  8. Synthesis and Photocytotoxicity of Mono-functionalised Porphyrin with Valine Moiety

    Institute of Scientific and Technical Information of China (English)

    Wei Min SHI; Jian WU; Yi Feng WU; Kai Xian QIAN

    2004-01-01

    A mono-funtionalised tetraphenylporphyrin (TPP) bearing valine moiety at the phenyl ring was synthesized for photocytotoxicity examination in four steps, starting from regiospecific mono-nitration of TPP at the phenyl ring. The in vitro photocytotoxicitic effect against SPC-A1 adenocarcinona cell line was tested.

  9. Magnetic and gravity studies of Mono Lake, east-central, California

    Science.gov (United States)

    Athens, Noah D.; Ponce, David A.; Jayko, Angela S.; Miller, Matt; McEvoy, Bobby; Marcaida, Mae; Mangan, Margaret T.; Wilkinson, Stuart K.; McClain, James S.; Chuchel, Bruce A.; Denton, Kevin M.

    2014-01-01

    From August 26 to September 5, 2011, the U.S. Geological Survey (USGS) collected more than 600 line-kilometers of shipborne magnetic data on Mono Lake, 20 line-kilometers of ground magnetic data on Paoha Island, 50 gravity stations on Paoha and Negit Islands, and 28 rock samples on Paoha and Negit Islands, in east-central California. Magnetic and gravity investigations were undertaken in Mono Lake to study regional crustal structures and to aid in understanding the geologic framework, in particular regarding potential geothermal resources and volcanic hazards throughout Mono Basin. Furthermore, shipborne magnetic data illuminate local structures in the upper crust beneath Mono Lake where geologic exposure is absent. Magnetic and gravity methods, which sense contrasting physical properties of the subsurface, are ideal for studying Mono Lake. Exposed rock units surrounding Mono Lake consist mainly of Quaternary alluvium, lacustrine sediment, aeolian deposits, basalt, and Paleozoic granitic and metasedimentary rocks (Bailey, 1989). At Black Point, on the northwest shore of Mono Lake, there is a mafic cinder cone that was produced by a subaqueous eruption around 13.3 ka. Within Mono Lake there are several small dacite cinder cones and flows, forming Negit Island and part of Paoha Island, which also host deposits of Quaternary lacustrine sediments. The typical density and magnetic properties of young volcanic rocks contrast with those of the lacustrine sediment, enabling us to map their subsurface extent.

  10. Enantioselective recognition of mono-demethylated methoxychlor metabolites by the estrogen receptor.

    Science.gov (United States)

    Miyashita, Masahiro; Shimada, Takahiro; Nakagami, Shizuka; Kurihara, Norio; Miyagawa, Hisashi; Akamatsu, Miki

    2004-02-01

    Metabolites of methoxychlor such as 2-(p-hydroxyphenyl)-2-(p-methoxyphenyl)-1,1,1-trichloroethane (mono-OH-MXC) and 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (bis-OH-MXC), have estrogenic activity. Mono-OH-MXC is a chiral compound in which the carbon atom bridging two benzene rings is the chiral centre. In previous studies the estrogenic activity of racemic mono-OH-MXC has been measured, and the activity of each enantiomer of this compound has not yet been elucidated. In this study, we evaluated the estrogen receptor-binding activity of each enantiomer of mono-OH-MXC to clarify the enantioselective recognition by the estrogen receptor. (S)-mono-OH-MXC showed 3-fold higher binding activity than that of the (R) enantiomer. The activity of bis-OH-MXC was only 1.7-fold higher than that of (S)-mono-OH-MXC. This result suggests that the one hydroxy group and the orientation of the CCl3 group of mono- and bis-OH-MXCs are important for the interaction with the estrogen receptor. The result also points out the estrogenic activity of methoxychlor after metabolic activation in vivo, which predominantly produces the (S)-mono-OH-MXC, may be higher than estimated from the in vitro activity of racemic mixtures.

  11. 陆梁油田薄层底水油藏水平井井筒模拟研究%Study on the Horizontal Wellbore Model of Thin-layered Bottom-water Reservoir in Luliang Oilfield

    Institute of Scientific and Technical Information of China (English)

    许维娜; 石军; 颜江; 范赛华; 何长坡

    2013-01-01

      新疆陆梁油田呼图壁河组油藏发育一类特殊的薄层底水型油藏,其特点是油层厚度薄,构造幅度低,底水能量大,利用水平井开采,表现出无水采油期短、含水率上升速度快、产量递减大的特点。针对这些问题,采用水平井数值模拟方法,建立了考虑摩擦压力损失的水平井井筒模型,明确了摩擦压力损失对水平井的压力分布以及水平段产量的影响,在此基础上,分析研究了水平井底水锥进的水脊特征,判断了水平井出水位置,提出了封堵出水井段并结合油藏工程方法确定了水平井合理产液量,从而达到抑制底水快速锥进,减小压力损失,降低含水率上升速度的目的。%A special thin layer of bottom water reservoir has developed in Hutubi River Layer in Luliang Oilfield of Xinjiang. This kind of reservoir has thin thickness,small sand body amplitude and large bottom-water energy. Drilled with horizontal well,this kind of reservoir has possessed some characteristics such as short water free production period and water-cut with faster ascending velocity and big decline production. Aiming at solving these problems,we established the horizontal well-bore model which takes the pressure loss into consideration with the numerical simulation method,and obtained the pressure distribution of horizontal wells and the influence of horizontal section production due to the pressure loss. On this basis,we analyzed the features of water cresting characteristic of the horizontal well bottom water coning,and judged the location of water breakthrough in horizontal section. Finally,the paper suggests that the reasonable liquid production can be achieved by plugging the location of water breakthrough and using pump which has smaller diameter. Such method will control bottom water coning and decrease the pressure loss and reduce the water cut increasing rate.

  12. 重力热管自吸地热改善热采井井筒热损失研究%A Study of Reducing Heat Loss of Thermal Recovery Wellbore by Gravity Heatpipe Technology through Absorbing Geothermal Energy

    Institute of Scientific and Technical Information of China (English)

    李龙; 李春生; 朱兰

    2011-01-01

    On the basis of the principle of gravity heat pipe decreasing heat loss in wellbore during thermal re covery and heat transfer of wellbore during oil production, calculation models of thermal energy engineering and heat transfer loss of wellbore were established and were used to calculate an example of testing well. The results show that the measured temperature of produced liquid is close to the calculated one, fractional error of which is 5.52%. The temperature of produced liquid inceases by 10℃ with gravity heatpipe in comparison with that of the regular wellbore, which could prove that gravity heatpipe is able to change the temperature distribution of fluids in wellbore. Gravity heatpipe absorbing geothermal energy is a new technology in oil production and can be applied to an extended extent in thermal recovery wells of heavy oil.%在深入探讨重力热管改善抽油井井筒热损失原理的基础上,结合井筒传热模型,建立了稠油热采井重力热管自吸热过程的热工计算及井筒热损失的计算模型.并结合矿场应用实例进行了计算.结果表明,井口产出液实测温度与计算值相对误差为5.52%,符合工程要求.热管正常工作后能将井口流体温度提高近10℃,在井筒中起到了平衡流体温场的作用.重力热管自吸地热采油技术是采油工程领域一项全新的探索,在稠油热采中有着广泛的应用前景.

  13. Collide and Conquer: Constraints on Simplified Dark Matter Models using Mono-X Collider Searches

    CERN Document Server

    Brennan, A J; Gramling, J; Jacques, T D

    2016-01-01

    The use of simplified models as a tool for interpreting dark matter collider searches has become increasingly prevalent, and while early Run II results are beginning to appear, we look to see what further information can be extracted from the Run I dataset. We consider three `standard' simplified models that couple quarks to fermionic singlet dark matter: an $s$-channel vector mediator with vector or axial-vector couplings, and a $t$-channel scalar mediator. Upper limits on the couplings are calculated and compared across three alternate channels, namely mono-jet, mono-$Z$ (leptonic) and mono-$W/Z$ (hadronic). The strongest limits are observed in the mono-jet channel, however the computational simplicity and absence of significant $t$-channel model width effects in the mono-boson channels make these a straightforward and competitive alternative. We also include a comparison with relic density and direct detection constraints.

  14. ANALYSIS OF EFFECT FACTOR IN SHALE WELLBORE STABILITY%泥页岩井壁稳定影响因素分析

    Institute of Scientific and Technical Information of China (English)

    王倩; 周英操; 唐玉林; 姜智博

    2012-01-01

    考虑泥页岩钻井液体系中电化势渗透产生的流体流动和离子运移以及与固体变形的联合作用,提出泥页岩井壁稳定耦合新模型.通过有限元计算泥页岩井壁周围孔隙压力场和应力场,分析泥页岩及钻井液性能参数对井壁周围地层坍塌破坏系数和坍塌压力的影响.研究结果表明,泥页岩渗透率增大,溶质扩散系数增大,泥页岩单位表面电荷数减小有利于泥页岩井壁稳定.通过使用高浓度、高反射系数的钻井液能够提高泥页岩井壁的稳定性,对于泥页岩地层使用过高的钻井液密度反而会导致井壁不稳定.泥页岩钻井液体系膨胀系数减小,泥页岩水化程度能够减轻.在钻井液浓度大于泥页岩孔隙流体浓度的情况下化学反渗透可能使泥页岩失水,与大尺寸井眼相比,小尺寸井眼坍塌破坏指数随时间变化较显著.%A new shale wellbore stability model considering fluid flow and ion transmission induced by shale-drilling fluid system electrochemical potential osmosis, and solid deformation resulted by solute diffusion, ion transmission and hydrate expansion is proposed. Pore pressure and stress field around the wellbore wall is computed by finite element method, and the effect of shale and drilling fluid parameters on collapse index and caving pressure is analyzed. The research results demonstrate that large shale permeability, large solute diffusion coefficient and small shale per unit surface charge are favour of shale stability. Drilling fluid with high concentration and reflection coefficient is beneficial for shale stability. High mud weight can sometimes result in instability for shale formation. While the swelling coefficient of shale-drilling fluid system decreases, the shale hydration can be alleviated. Especially for the case that the drilling fluid concentration is larger than the shale pore fluid, the chemical reverse osmosis may cause shale dehydration. The collapse index

  15. LED-based digital diameter measurement

    Science.gov (United States)

    Kleuver, Wolfram; Becker, Lothar

    1995-01-01

    This paper presents a new industrial sensor for measuring diameters of extreme thin objects. The system is divided in two parts. The first is the emitter and the second the receiver. It is possible to use this system for the automatic inspection of files and wires in the textile industries and wire works. Another application for the sensor is the control of production of chemical files in an extruder. Furthermore we can measure more than one object in the lightbeam because we get information not only about the dimensions also about the position of the objects in the beam. The innovation in this system is the using of a light emitting diode (LED) as emitter and the realization of a long distance of about two or more meters between the two sensorheads. The results of this development are a special kind of optical layout in the emitter to reduce the loss of intensity and minimize the divergence of the lightbeam. It is not necessary to develop an intensity distribution, which is equal over the complete width of the sensorhead. We can show that we have a better dynamic in the system with this feature. The experiments prove that we get the same resolution as a laserbeamsensor. Furthermore one advantage is the eye-safety.

  16. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Mono- and diglycerides of edible fats or oils, or... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. (a) Product. Mono- and diglycerides of edible fats or oils, or edible...

  17. Catalytic Activity of Mono- and Bi-Metallic Nanoparticles Synthesized via Microemulsions

    Directory of Open Access Journals (Sweden)

    Ramona Y.G. König

    2014-07-01

    Full Text Available Water-in-oil (w/o microemulsions were used as a template for the synthesis of mono- and bi-metallic nanoparticles. For that purpose, w/o-microemulsions containing H2PtCl6, H2PtCl6 + Pb(NO32 and H2PtCl6 + Bi(NO3, respectively, were mixed with a w/o-microemulsion containing the reducing agent, NaBH4. The results revealed that it is possible to synthesize Pt, PtPb and PtBi nanoparticles of ~3–8 nm in diameter at temperatures of about 30°C. The catalytic properties of the bimetallic PtBi and PtPb nanoparticles were studied and compared with monometallic platinum nanoparticles. Firstly, the electrochemical oxidation of formic acid to carbon monoxide was investigated, and it was found that the resistance of the PtBi and PtPb nanoparticles against the catalyst-poisoning carbon monoxide was significantly higher compared to the Pt nanoparticles. Secondly, investigating the reduction of 4-nitrophenol to 4-aminophenol,we found that the bimetallic NPs are most active at 23 °C, while the order of the activity changes at higher temperatures, i.e., that the Pt nanoparticles are the most active ones at 36 and 49 °C. Furthermore, we observed a strong influence of the support, which was either a polymer or Al2O3. Thirdly, for the hydrogenation of allylbenzene to propylbenzene, the monometallic Pt NPs turned out to be the most active catalysts, followed by the PtPb and PtBi NPs. Comparing the two bimetallic nanoparticles, one sees that the PtPb NPs are significantly more active than the respective PtBi NPs.

  18. Mockup Small-Diameter Air Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    A. Poerschke and A. Rudd

    2016-05-01

    This report investigates the feasibility of using a home-run manifold small-diameter duct system to provide space conditioning air to individual thermal zones in a low-load home. This compact layout allows duct systems to be brought easily within conditioned space via interior partition walls. Centrally locating the air hander unit in the house significantly reduces duct lengths. The plenum box is designed so that each connected duct receives an equal amount of airflow, regardless of the duct position on the box. Furthermore, within a reasonable set of length restrictions, each duct continues to receive similar airflow. The design method uses an additive approach to reach the total needed zonal airflow. Once the cubic feet per minute needed to satisfy the thermal load of a zone has been determined, the total number of duct runs to a zone can be calculated by dividing the required airflow by the standard airflow from each duct. The additive approach greatly simplifies the design effort and reduces the potential for duct design mistakes to be made. Measured results indicate that this plenum design can satisfy the heating load. However, the total airflow falls short of satisfying the cooling load in a hypothetical building. Static pressure inside the plenum box of 51.5 Pa limited the total airflow of the attached mini-split heat pump blower, thus limiting the total thermal capacity. Fan energy consumption is kept to 0.16 to 0.22 watt/CFM by using short duct runs and smooth duct material.

  19. Separation of mono- and di-PEGylate of exenatide and resolution of positional isomers of mono-PEGylates by preparative ion exchange chromatography.

    Science.gov (United States)

    Nguyen, Ngoc-Thanh Thi; Lee, Jae Sun; Yun, Soi; Lee, E K

    2016-07-29

    Exenatide is a synthetic version of the 39-mer peptide of Exendin-4, which is an FDA-approved therapeutic against Type II diabetes mellitus. However, exenatide has a very short in-serum half-life and PEGylation have been performed to improve its in-serum stability. PEGylation often yields multivalent binding to non-specific residues, and the desired species should be carefully separated by chromatographies. In this study, we first devised an aqueous-phase, two-step PEGylation process. This consists of thiolation of Lys 12 and 27 residues followed by attachment of PEG-maleimide (10kD) to thiol groups. This process yields various species: mono-PEGylates with positional isomers, di-PEGylate, and other higher MW substances. A prep-grade cationic exchange chromatography (HiTrap SP) at pH 3.0 partially separated mono- and di-PEGylates based on the molar ratio of conjugated PEG and peptide and thus molecular weight of the conjugates. To further investigate the chromatographic separation of positional isomers of mono-PEGylates, we prepared two kinds of exenatide analogs by point mutation; K12C and K27C. Each analog was mono-PEGylated with very high yield (>95%). When a mixture of the two positional isomers of mono-PEGylates was applied to HiTrap SP chromatography, K12C-PEGylate and K27C-PEGylate eluted separately at 0.22M and 0.33M NaCl, respectively. When the proportions of acid and its conjugate base of the amino acid residues adjacent to the PEGylation site at pH 3.0 were analyzed, K27C-PEGylate shows stronger positive charge than K12C-PEGylate, and we propose the residence time difference between the two mono-PEGylates could be due to the charge difference. ELISA result shows that the immuno-binding activity of both analogs and their mono-PEGylates are well maintained. Furthermore, both mono-PEGylates of the analogs show higher than 50-fold improved anti-trypsin stability. We expect that mono-PEGylates of the exenatide analogs are alternatives to the conventional C40

  20. Body diameters in 3 - 6 years old children from Plovdiv

    Directory of Open Access Journals (Sweden)

    Tineshev Slavi

    2013-01-01

    Full Text Available The purpose of the research is to analyze the body diameters in 3-6 year old children. The biacromial diameters were taken as well as the two chest diameters, the bicristal and bitrohanterial diameters in 316 children (157 boys and 159 girls 3, 4, 5 and 6 years of age attending kindergarten in Plovdiv. The analysis shows that all diameters, with the exception of the bitrohanterial have higher values in boys. The absolute year's increment of the diameters is greater in girls. The growth velocity of the researched features is greatest at the age of 3-4 and 4-5, decreasing at different rates for the different features at the age of 5-6. The only exception is the sagittal chest diameter in both sexes and the bitrohanterial diameters in girls.

  1. Interaction of potassium mono and di phosphates with bovine serum albumin studied by fluorescence quenching method.

    Science.gov (United States)

    Bakkialakshmi, S; Shanthi, B; Chandrakala, D

    2011-03-01

    The interactions between potassium mono and di phosphates and bovine serum albumin (BSA) were studied using fluorescence spectroscopy (FS) and ultraviolet spectroscopy (UV). The experimental results showed that the potassium mono and di phosphates could insert into the BSA and quench the inner fluorescence of BSA by forming the potassium mono phosphate-BSA and pottassium di phosphate-BSA complexes. It was found that the static quenching was the main reason leading to the fluorescence quenching. It was conformed by XRD and SEM techniques.

  2. Professional iPhone Programming with MonoTouch and .NET/C#

    CERN Document Server

    McClure, Wallace B; Dunn, Craig

    2010-01-01

    What .NET C# developers need to enter the hot field of iPhone apps. iPhone applications offer a hot opportunity for developers. Until the open source MonoTouch project, this field was limited to those familiar with Apple's programming languages. Now .NET and C# developers can join the party. This Wrox guide is the first book to cover MonoTouch, preparing developers to take advantage of this lucrative opportunity.: MonoTouch opens the field of iPhone app development to .NET and C# developers for the first time; the Wrox reputation among .NET developers assures them that this guide covers everyt

  3. A new approach to modelling and designing mono-block dental implants

    OpenAIRE

    R. Hunter; F. Alister; Möller, J.; J. Alister

    2007-01-01

    Purpose: of this paper is present a new approach to modelling and design the low cost mono-block dental implants based on the integration of the computer aided techniques. This approach provides the automation of the design process of the mono-block dental implants.Design/methodology/approach: The approach used to develop the modelling and design of the mono-block dental implants are based on the parametrization of the main geometric features of the implants. This approach allows to generate ...

  4. Develop mono-block tooth implants using automate design and FEM analysis

    OpenAIRE

    J.P. Alister; J. Moller,; F. Alister; R. Hunter

    2007-01-01

    Purpose: Purpose of this paper is present a new approach to modelling and design the low cost mono-block dental implants based on the integration of the computer aided techniques. This approach provides the automation of the design process of the mono-block dental implants.Design/methodology/approach: The approach used to develop the modelling and design of the mono-block dental implants are based on the parametrization of the main geometric features of the implants. This approach allows to ...

  5. Spray cone angle and air core diameter of hollow cone swirl rocket injector

    Directory of Open Access Journals (Sweden)

    Ahmad Hussein Abdul Hamid

    2011-12-01

    Full Text Available ABSTRACT : Fuel injector for liquid rocket is a very critical component since that small difference in its design can dramatically affect the combustion efficiency. The primary function of the injector is to break the fuel up into very small droplets. The smaller droplets are necessary for fast quiet ignition and to establish a flame front close to the injector head, thus shorter combustion chamber is possible to be utilized. This paper presents an experimetal investigation of a mono-propellant hollow cone swirl injector. Several injectors with different configuration were investigated under cold flow test, where water is used as simulation fluid. This investigation reveals that higher injection pressure leads to higher spray cone angle. The effect of injection pressure on spray cone angle is more prominent for injector with least number of tangential ports. Furthermore, it was found that injector with the most number of tangential ports and with the smallest tangential port diameter produces the widest resulting spray. Experimental data also tells that the diameter of an air core that forms inside the swirl chamber is largest for the injector with smallest tangential port diameter and least number of tangential ports.ABSTRAK : Injektor bahan api bagi roket cecair merupakan satu komponen yang amat kritikal memandangkan perbezaan kecil dalam reka bentuknya akan secara langsung mempengaruhi kecekapan pembakaran. Fungsi utama injektor adalah untuk memecahkan bahan api kepada titisan yang amat kecil. Titisan kecil penting untuk pembakaran pantas secara senyap dan untuk mewujudkan satu nyalaan di hadapan, berhampiran dengan kepala injektor, maka kebuk pembakaran yang lebih pendek berkemungkinan dapat digunakan. Kertas kerja ini mebentangkan satu penyelidikan eksperimental sebuah injektor ekabahan dorong geronggang kon pusar. Beberapa injektor dengan konfigurasi berbeza telah dikaji di bawah ujian aliran sejuk, di mana air digunakan sebagai bendalir

  6. Numerical Simulation of Large Diameter Cylindrical Structure Slamming

    Institute of Scientific and Technical Information of China (English)

    XU Jing; WANG De-yu

    2008-01-01

    The water entry of large diameter cylindrical structure is studied by applying numerical simulation method. The processes of different diameter cylindrical structures impacting water with various constant velocities are calculated numerically. Thereafter, analyzed are the distribution of slamming pressure on structure during slamming course and the influence of slamming velocity and cylindrical diameter on slamming process. Furthermore, presented herein is an equation being used to forecast the peak slamming force on a large diameter cylindrical structure.

  7. Effects of forest fragmentation on the mating system of a cool-temperate heterodichogamous tree Acer mono

    Directory of Open Access Journals (Sweden)

    Satoshi Kikuchi

    2015-01-01

    Full Text Available Pollination is a key process for reproduction and gene flow in flowering plants. Anthropogenic habitat fragmentation, however, can disrupt plant–pollinator interactions, and may have a negative impact on the reproductive success and population viability of entomophilous plants. Heterodichogamous plants containing protandrous and protogynous individuals within a population may be susceptible to habitat fragmentation due to a lack of available mating partners. In this study, we investigated the effects of forest fragmentation on the mating system in the heterodichogamous plant Acer mono, a major constituent of cool-temperate deciduous forests in Japan. Microsatellite analysis was applied to 212 adult trees and 17 seed families from continuous and fragmented forests. Dispersal kernel modeling using the neighborhood model indicated that pollen dispersal of A. mono was highly fat-tailed. The estimated parameters of the model suggested that the siring success of a pollen donor increased approximately fivefold, with a 100 cm increase in its diameter at breast height (DBH, and that disassortative mating was five times more frequent than assortative mating. The mating system parameters of each mother tree, outcrossing rate (tm, biparental inbreeding (tm−ts, and paternity correlation (rpm varied among sites and conditions, depending on the local density of potential pollen donors. Whereas A. mono was effectively outcrossed (tm=0.901, tm−ts=0.052, and the number of effective sires was 1/rpm=14.93 in the continuous forest, clumped trees within the fragmented forest showed increased biparental inbreeding and reduced pollen pool genetic diversity (tm=0.959, tm−ts=0.245,1/rpm=1.742 as a result of localized mating combined with spatial genetic structures. In contrast, the isolated trees had a higher selfing rate, but the pollen pool diversity was maintained (tm=0.801, tm−ts=0.022, and 1/rpm=15.63 due to frequent long-distance pollination. These

  8. A Mono Master Shrug Matching Algorithm for Examination Surveillance

    Directory of Open Access Journals (Sweden)

    Sandhya Devi G

    2014-12-01

    Full Text Available This paper proposes an unusual slant for Shrug recognition from Gesticulation Penetrated Images (GPI based on template matching. Shrugs can be characterized with image templates which are used to compare and match shrugs. The proposed technique makes use of a single template to identify match in the candidates and hence entitled as mono master shrug matching. It does not necessitate erstwhile acquaintance of movements, motion estimation or tracking. The proposed technique brands a unique slant to isolate various shrugs from a given video. Additionally, this method is based on the reckoning of feature invariance to photometric and geometric variations from a given video for the rendering of the shrugs in a lexicon. This descriptor extraction method includes the standard deviation of the gesticulation penetrated images of a shrug. The comparison is based on individual and rational actions with exact definitions varying widely uses histogram based tracker which computes the deviation of the candidate shrugs from the template shrug. Far-reaching investigation is done on a very intricate and diversified dataset to establish the efficacy of retaining the anticipated method.

  9. Adding Mono- and Multivalent Ions to Lyotropic Chromonic Liquid Crystals

    Science.gov (United States)

    Tortora, Luana; Park, Heung-Shik; Antion, Kelly; Woolwerton, Chris; Finotello, Daniele; Lavrentovich, Oleg

    2006-03-01

    Lyotropic Chromonic Liquid Crystals (LCLCs) are a distinct class of liquid crystals formed in aqueous solutions by molecules with rigid polyaromatic cores and ionic groups at the periphery [1-4]. The phase diagrams of these materials should depend on entropic factors (as in the Onsager model) and electrostatic interactions. Using optical polarizing microscopy, we studied the effects of mono- and multivalent ions on the phase diagrams of Blue 27 [3] and Sunset Yellow [2]. The monovalent ions change the temperatures of phase transitions, as described in [4], while the effect of multivalent ions is more dramatic and, in addition to the changed temperatures of phase transitions by tens of degrees, it often involves condensation of LCLC aggregates into domains with birefringence much higher than that in a normal nematic phase. Work supported by OBR B-7844. [1]J. Lydon, Current Opin. Colloid & Interface Sci. 3, 458 (1998);8, 480-489 (2004); [2]V. R. Horowitz, L. A. Janowitz, A. L. Modic, P. J. Heiney, and P. J. Collings, 2005, Phys. Rew. E 72, 041710; [3]Yu. A. Nastishin, H. Liu, T. Schneider, T., V. Nazarenko, R. Vasyuta, S. V. Shiyanovskii, and O. D. Lavrentovich, 2005, Phys. Rev. E 72, 041711; [4]A.F. Kostko, B. H. Cipriano, O. A. Pinchuk, L. Ziserman, M. A. Anisimov, D. Danino, and S. R. Raghavan. J. Phys. Chem. B 109, 19126-19133 (2005)

  10. Similar Sister Chromatid Arrangement in Mono- and Holocentric Plant Chromosomes.

    Science.gov (United States)

    Schubert, Veit; Zelkowski, Mateusz; Klemme, Sonja; Houben, Andreas

    2016-01-01

    Due to the X-shape formation at somatic metaphase, the arrangement of the sister chromatids is obvious in monocentric chromosomes. In contrast, the sister chromatids of holocentric chromosomes cannot be distinguished even at mitotic metaphase. To clarify their organization, we differentially labelled the sister chromatids of holocentric Luzula and monocentric rye chromosomes by incorporating the base analogue EdU during replication. Using super-resolution structured illumination microscopy (SIM) and 3D rendering, we found that holocentric sister chromatids attach to each other at their contact surfaces similar to those of monocentrics in prometaphase. We found that sister chromatid exchanges (SCEs) are distributed homogeneously along the whole holocentric chromosomes of Luzula, and that their occurrence is increased compared to monocentric rye chromosomes. The SCE frequency of supernumerary B chromosomes, present additionally to the essential A chromosome complement of rye, does not differ from that of A chromosomes. Based on these results, models of the sister chromatid arrangement in mono- and holocentric plant chromosomes are presented.

  11. Fringing in MonoCam Y4 filter images

    Science.gov (United States)

    Brooks, J.; Fisher-Levine, M.; Nomerotski, A.

    2017-05-01

    We study the fringing patterns observed in MonoCam, a camera with a single Large Synoptic Survey Telescope (LSST) CCD sensor. Images were taken at the U.S. Naval Observatory in Flagstaff, Arizona (NOFS) employing its 1.3 m telescope and an LSST y4 filter. Fringing occurs due to the reflection of infrared light (700 nm or larger) from the bottom surface of the CCD which constructively or destructively interferes with the incident light to produce a net ``fringe'' pattern which is superimposed on all images taken. Emission lines from the atmosphere, dominated by hydroxyl (OH) spectra, can change in their relative intensities as the night goes on, producing different fringe patterns in the images taken. We found through several methods that the general shape of the fringe patterns remained constant, though with slight changes in the amplitude and phase of the fringes. We also found that a superposition of fringes from two monochromatic lines taken in the lab offered a reasonable description of the sky data.

  12. THE RECOGNITION OF SPOKEN MONO-MORPHEMIC COMPOUNDS IN CHINESE

    Directory of Open Access Journals (Sweden)

    Yu-da Lai

    2012-12-01

    Full Text Available This paper explores the auditory lexical access of mono-morphemic compounds in Chinese as a way of understanding the role of orthography in the recognition of spoken words. In traditional Chinese linguistics, a compound is a word written with two or more characters whether or not they are morphemic. A monomorphemic compound may either be a binding word, written with characters that only appear in this one word, or a non-binding word, written with characters that are chosen for their pronunciation but that also appear in other words. Our goal was to determine if this purely orthographic difference affects auditory lexical access by conducting a series of four experiments with materials matched by whole-word frequency, syllable frequency, cross-syllable predictability, cohort size, and acoustic duration, but differing in binding. An auditory lexical decision task (LDT found an orthographic effect: binding words were recognized more quickly than non-binding words. However, this effect disappeared in an auditory repetition and in a visual LDT with the same materials, implying that the orthographic effect during auditory lexical access was localized to the decision component and involved the influence of cross-character predictability without the activation of orthographic representations. This claim was further confirmed by overall faster recognition of spoken binding words in a cross-modal LDT with different types of visual interference. The theoretical and practical consequences of these findings are discussed.

  13. Antioxidant and cytotoxic activity of mono- and bissalicylic acid derivatives

    Directory of Open Access Journals (Sweden)

    Đurendić Evgenija A.

    2014-01-01

    Full Text Available A simple synthesis of mono- and bis-salicylic acid derivatives 1-10 by the transesterification of methyl salicylate (methyl 2-hydroxybenzoate with 3-oxapentane-1,5-diol, 3,6- dioxaoctane-1,8-diol, 3,6,9-trioxaundecane-1,11-diol, propane-1,2-diol or 1-aminopropan- 2-ol in alkaline conditions is reported. All compounds were tested in vitro on three malignant cell lines (MCF-7, MDA-MB-231, PC-3 and one non-tumor cell line (MRC- 5. Strong cytotoxicity against prostate PC-3 cancer cells expressed compounds 3, 4, 6, 9 and 10, all with the IC50 less than 10 μmol/L, which were 11-27 times higher than the cytotoxicity of antitumor drug doxorubicin. All tested compounds were not toxic against the non-tumor MRC-5 cell line. Antioxidant activity of the synthesized derivatives was also evaluated. Compounds 2, 5 and 8 were better OH radical scavengers than commercial antioxidants BHT and BHA. The synthesized compounds showed satisfactory scavenger activity, which was studied by QSAR modeling. A good correlation between the experimental variables IC50 DPPH and IC50 OH and MTI (molecular topological indices molecular descriptors and CAA (accessible Connolly solvent surface area for the new compounds 1, 3, and 5 was observed.

  14. Mono-energy coronary angiography with a compact light source

    Science.gov (United States)

    Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noël, Peter B.; Pfeiffer, Franz; Muenzel, Daniela

    2017-03-01

    While conventional x-ray tube sources reliably provide high-power x-ray beams for everyday clinical practice, the broad spectra that are inherent to these sources compromise the diagnostic image quality. For a monochromatic x-ray source on the other hand, the x-ray energy can be adjusted to optimal conditions with respect to contrast and dose. However, large-scale synchrotron sources impose high spatial and financial demands, making them unsuitable for clinical practice. During the last decades, research has brought up compact synchrotron sources based on inverse Compton scattering, which deliver a highly brilliant, quasi-monochromatic, tunable x-ray beam, yet fitting into a standard laboratory. One application that could benefit from the invention of these sources in clinical practice is coronary angiography. Being an important and frequently applied diagnostic tool, a high number of complications in angiography, such as renal failure, allergic reaction, or hyperthyroidism, are caused by the large amount of iodine-based contrast agent that is required for achieving sufficient image contrast. Here we demonstrate monochromatic angiography of a porcine heart acquired at the MuCLS, the first compact synchrotron source. By means of a simulation, the CNR in a coronary angiography image achieved with the quasi-mono-energetic MuCLS spectrum is analyzed and compared to a conventional x-ray-tube spectrum. The results imply that the improved CNR achieved with a quasi-monochromatic spectrum can allow for a significant reduction of iodine contrast material.

  15. The diameter-dependent photoelectrochemical performance of silicon nanowires.

    Science.gov (United States)

    Zhang, Bing-Chang; Wang, Hui; He, Le; Duan, Chun-Yang; Li, Fan; Ou, Xue-Mei; Sun, Bao-Quan; Zhang, Xiao-Hong

    2016-01-25

    We demonstrate the first systematic study of the diameter-dependent photoelectrochemical performance of single silicon nanowires within a broad size range from 200 to 2000 nm. SiNWs with a diameter of 1415 nm exhibit the highest solar energy conversion efficiency, which can be mainly traced to their diameter-dependent light absorption properties.

  16. Mono-Cycle Photonics and Optical Scanning Tunneling Microscopy Route to Femtosecond Ångstrom Technology

    CERN Document Server

    Yamashita, Mikio; Morita, Ryuji

    2005-01-01

    "Mono-Cycle Photonics and Optical Scanning Tunneling Microscopy" deals with both the ultrashort laser-pulse technology in the few- to mono-cycle region and the laser-surface-controlled scanning-tunneling microscopy (STM) extending into the spatiotemporal extreme technology. The former covers the theory of nonlinear pulse propagation beyond the slowly-varing-envelope approximation, the generation and active chirp compensation of ultrabroadband optical pulses, the amplitude and phase characterization of few- to mono-cycle pulses, and the feedback field control for the mono-cycle-like pulse generation. In addition, the wavelength-multiplex shaping of ultrabroadband pulse is described. The latter covers the CW-laser-excitation STM, the femtosecond-time-resolved STM and atomic-level surface phenomena controlled by femtosecond pulses.

  17. Developing C# Apps for iPhone and iPad using MonoTouch

    CERN Document Server

    Costanich, Bryan

    2011-01-01

    Developing C# Applications for iPhone and iPad using MonoTouch shows you how to use your existing C# skills to write apps for the iPhone and iPad. Fortunately, there's MonoTouch, Novell's .NET library that allows C# developers to write C# code that executes in iOS. Furthermore, MonoTouch allows you to address all the unique functions of the iPhone, iPod Touch, and iPad. And the big plus: You needn't learn any Objective-C to master MonoTouch!. Former Microsoft engineer and published app-store developer Bryan Costanich shows you how to use the tools you already know to create native apps in iOS

  18. Repairing split ends: SIRT6, mono-ADP ribosylation and DNA repair

    Science.gov (United States)

    Van Meter, Michael; Mao, Zhiyong; Gorbunova, Vera; Seluanov, Andrei

    2011-01-01

    The sirtuin gene family comprises an evolutionarily ancient set of NAD+ dependent protein deacetylase and mono-ADP ribosyltransferase enzymes. Found in all domains of life, sirtuins regulate a diverse array of biological processes, including DNA repair, gene silencing, apoptosis and metabolism. Studies in multiple model organisms have indicated that sirtuins may also function to extend lifespan and attenuate age-related pathologies. To date, most of these studies have focused on the deacetylase activity of sirtuins, and relatively little is known about the other biochemical activity of sirtuins, mono-ADP ribosylation. We recently reported that the mammalian sirtuin, SIRT6, mono-ADP ribosylates PARP1 to promote DNA repair in response to oxidative stress. In this research perspective we review the role of SIRT6 in DNA repair and discuss the emerging implications for sirtuin directed mono-ADP ribosylation in aging and age-related diseases. PMID:21946623

  19. Synthesis of mono-dispersed nanofluids using solution plasma

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Yong Kang, E-mail: yk@rd.numse.nagoya-u.ac.jp [Graduate School of Materials Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); Bratescu, Maria Antoaneta, E-mail: maria@rd.numse.nagoya-u.ac.jp [Graduate School of Materials Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); Knowledge Hub Aichi, Yakusa-cho, Nagakute-ku, Toyota (Japan); Ueno, Tomonaga, E-mail: tomo@rd.numse.nagoya-u.ac.jp [Graduate School of Materials Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); CREST, Japan Science and Technology Agency, Goban-cho, Chiyoda-ku, Tokyo (Japan); Saito, Nagahiro, E-mail: hiro@rd.numse.nagoya-u.ac.jp [Graduate School of Materials Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); Knowledge Hub Aichi, Yakusa-cho, Nagakute-ku, Toyota (Japan); Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan); CREST, Japan Science and Technology Agency, Goban-cho, Chiyoda-ku, Tokyo (Japan)

    2014-07-14

    Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by electrical discharge in liquid environment using termed solution plasma processing (SPP). Electrons and the hydrogen radicals are reducing the gold ions to the neutral form in plasma gas phase and liquid phase, respectively. The gold NPs have the smallest diameter of 4.9 nm when the solution temperature was kept at 20 °C. Nucleation and growth theory describe the evolution of the NP diameter right after the reduction reaction in function of the system temperature, NP surface energy, dispersion energy barrier, and nucleation rate. Negative charges on the NPs surface during and after SPP generate repulsive forces among the NPs avoiding their agglomeration in solution. Increasing the average energy in the SPP determines a decrease of the zeta potential and an increase of the NPs diameter. An important enhancement of the thermal conductivity of 9.4% was measured for the synthesized nanofluids containing NPs with the smallest size.

  20. Synthesis of mono-dispersed nanofluids using solution plasma.

    Science.gov (United States)

    Heo, Yong Kang; Bratescu, Maria Antoaneta; Ueno, Tomonaga; Saito, Nagahiro

    2014-07-14

    Small-sized and well-dispersed gold nanoparticles (NPs) for nanofluidics have been synthesized by electrical discharge in liquid environment using termed solution plasma processing (SPP). Electrons and the hydrogen radicals are reducing the gold ions to the neutral form in plasma gas phase and liquid phase, respectively. The gold NPs have the smallest diameter of 4.9 nm when the solution temperature was kept at 20 °C. Nucleation and growth theory describe the evolution of the NP diameter right after the reduction reaction in function of the system temperature, NP surface energy, dispersion energy barrier, and nucleation rate. Negative charges on the NPs surface during and after SPP generate repulsive forces among the NPs avoiding their agglomeration in solution. Increasing the average energy in the SPP determines a decrease of the zeta potential and an increase of the NPs diameter. An important enhancement of the thermal conductivity of 9.4% was measured for the synthesized nanofluids containing NPs with the smallest size.

  1. The k-Diameter of a Kind of Circulant Graph

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-di

    2004-01-01

    The diameter of a graph G is the maximal distance between pairs of vertices of G. When a network is modeled as a graph,diameter is a measurement for maximum transmission delay. The k-diameter dk(G) of a graph G, which deals with k internally disjoint paths between pairs of vertices of G, is a extension of the diameter of G. It has widely studied in graph theory and computer science. The circulant graph is a group-theoretic model of a class of symmetric interconnection network. Let Cn(i, ) be a circulant graph of order n whose spanning elements are i and , where n≥4 and n is even. In this paper, the diameter, 2-diameter and 3-diameter of the Cn(i,) are all obtained if gcd(n,i)=1, where the symbol gcd(n,i) denotes the maximum common divisor of n and i.

  2. Tool Geometry for Friction Stir Welding—Optimum Shoulder Diameter

    Science.gov (United States)

    Mehta, M.; Arora, A.; de, A.; Debroy, T.

    2011-09-01

    The most important geometric parameter in the friction stir welding (FSW) tool design is the shoulder diameter, which is currently estimated by trial and error. Here, we report a combined experimental and theoretical investigation on the influence of shoulder diameter on thermal cycles, peak temperatures, power requirements, and torque during FSW of AA7075-T6. An optimum tool shoulder diameter is identified using a three-dimensional, heat transfer and materials flow model. First, the predictive capability of the model is tested by comparing the computed values of peak temperature, spindle power, and torque requirements for various shoulder diameters against the corresponding experimental data. The change in the values of these variables with shoulder diameter is correctly predicted by the model. The model is then used to identify the optimum tool shoulder diameter that facilitates maximal use of the supplied torque in overcoming interfacial sticking. The tool with optimum shoulder diameter is shown to result in acceptable yield strength (YS) and ductility.

  3. Mono-X, dijet, and long-lived particle searches at the LHC

    CERN Document Server

    McDonald, Emily; The ATLAS collaboration

    2016-01-01

    This document presents a summary of the most recent Run II searches and results in the mono-X (photon, Z/W/H), mono-/di-jet, and long-lived particle channels for the ATLAS and CMS experiments. Limits on Simplified Models of dark matter and Effective Field Theories in each channel are also presented where relevant as a complement to the SUSY, BSM Higgs, and Invisible Higgs results which are to be covered in a separate presentation.

  4. Baker's yeast mediated reduction of substituted acenaphthenequinones: Regio- and enantioselective preparation of mono-hydroxyacenaphthenones

    Institute of Scientific and Technical Information of China (English)

    Xing Yong Wang; Jing Nan Cui; Wei Min Ren; Feng Li; Chun Liang Lu; Xu Hong Qian

    2007-01-01

    Baker's yeast mediated reduction of acenaphthenequinone within 4-10 h afforded mono-hydroxyacenaphthenone mainly with low enantioselectivity, the substrate and mono-hydroxyacenaphthenone product almost converted to dihydroxyacenaphthene after 48 h.By control of the reaction time and in the presence of DMF as co-solvent, the reduction of 6-substituted acenaphthenequinones under vigorous agitation afforded the corresponding 2-hydroxyacenaphthenones in 24-84% yields with 10-93% ee.

  5. Evidence that Mono-ADP-Ribosylation of CtBP1/BARS Regulates Lipid Storage

    OpenAIRE

    Bartz, René; Seemann, Joachim; Zehmer, John K.; Serrero, Ginette; Kent D. Chapman; Anderson, Richard G. W.; Liu, Pingsheng

    2007-01-01

    Mono-ADP-ribosylation is emerging as an important posttranslational modification that modulates a variety of cell signaling pathways. Here, we present evidence that mono-ADP-ribosylation of the transcriptional corepressor C terminal binding protein, brefeldin A (BFA)-induced ADP-ribosylated substrate (CtBP1/BARS) regulates neutral lipid storage in droplets that are surrounded by a monolayer of phospholipid and associated proteins. CtBP1/BARS is an NAD-binding protein that becomes ribosylated ...

  6. Geothermal systems of the Mono Basin-Long Valley region, eastern California and western Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, C.T.; Flynn, T.; Chapman, R.H.; Trexler, D.T.; Chase, G.R.; Bacon, C.F.; Ghusn, G. Jr.

    1985-01-01

    The region that includes Mono Basin, Long Valley, the Bridgeport-Bodie Hills area, and Aurora, in eastern California and western Nevada was studied to determine the possible causes and interactions of the geothermal anomalies in the Mono Basin-Long Valley region as a whole. A special goal of the study was to locate possible shallow bodies of magma and to determine their influence on the hydrothermal systems in the region. (ACR)

  7. Characteristics of Angora rabbit fiber using optical fiber diameter analyzer.

    Science.gov (United States)

    Rafat, S A; de Rochambeau, H; Brims, M; Thébault, R G; Deretz, S; Bonnet, M; Allain, D

    2007-11-01

    An experiment was conducted to describe the characteristics of Angora rabbit fiber using optical fiber diameter analyzer (OFDA). A total of 349 fleece samples were collected from 60 French Angora rabbits. Recorded measurements of OFDA were as follows: mean fiber diameter, CV of fiber diameter, comfort factor, spinning fineness, mean fiber curvature, SD of fiber curvature, mean opacity of fibers, percentage of medullated fibers, mean fiber diameter along the length, and SD of fiber diameter along the length. Comfort factor is the percentage of fibers less than or equal to 30 microns. The main effects included in the mixed model were fixed effects of group, harvest season, and age and a random effect of animal. Correlations among total fleece weight, compression, and OFDA measurements were calculated. Mean fiber diameter was lower than the fiber diameter along the length. Mean percentage of medullated fibers was very low and ranged from 0.1 to 7.3%. The mean comfort factor was 97.5% and ranged from 93.3 to 99.8%. The mean fiber curvature was 40.1 degrees/mm. The major changes in Angora fleece characteristics from 8 to 105 wk of age were an increase in fiber diameter, CV of fiber diameter, mean fiber diameter along the length and curvature, and a decrease in compression and comfort factor. The effect of harvest season was significant on some fiber characteristics. Mean fiber diameter and the mean fiber diameter along the length had a positive correlation with total fleece weight. The OFDA methodology is a method to evaluate fiber diameter, CV of fiber diameter, and bristle content through measuring of the comfort factor. However, OFDA is not adapted for measuring opacity or size of the medulla, or both, in Angora wool and needs a new definition or a special calibration. The spinning fineness should be redefined and adapted for Angora rabbits.

  8. Estimation of genetic parameters for wool fiber diameter measures.

    Science.gov (United States)

    Iman, N Y; Johnson, C L; Russell, W C; Stobart, R H

    1992-04-01

    Genetic and phenotypic correlations and heritability estimates of side, britch, and core diameters; side and britch CV; side and britch diameter difference; and clean fleece weight were investigated using 385 western white-faced ewes produced by 50 sires and maintained at two locations on a selection study. Data were analyzed using analysis of variance procedures, and effects in the final model included breed of sire-selection line combination, sire within breed-selection line, and location. Heritabilities were estimated by paternal half-sib analysis. Sires within breed-selection line represented a significant source of variation for all traits studied. Location had a significant effect on side diameter, side and britch diameter difference, and clean fleece weight. Age of ewe only affected clean fleece weight. Phenotypic and genetic correlations among side, britch, and core diameter measures were high and positive. Phenotypic correlations ranged from .68 to .75 and genetic correlations ranged from .74 to .89. The genetic correlations between side and britch diameter difference and side diameter or core diameter were small (-.16 and .28, respectively). However, there was a stronger genetic correlation between side and britch diameter difference and britch diameter (.55). Heritability of the difference between side and britch diameter was high (.46 +/- .16) and similar to heritability estimates reported for other wool traits. Results of this study indicate that relatively rapid genetic progress through selection for fiber diameter should be possible. In addition, increased uniformity in fiber diameter should be possible through selection for either side and britch diameter difference or side or britch CV.

  9. Discovery and industrial applications of lytic polysaccharide mono-oxygenases.

    Science.gov (United States)

    Johansen, Katja S

    2016-02-01

    The recent discovery of copper-dependent lytic polysaccharide mono-oxygenases (LPMOs) has opened up a vast area of research covering several fields of application. The biotech company Novozymes A/S holds patents on the use of these enzymes for the conversion of steam-pre-treated plant residues such as straw to free sugars. These patents predate the correct classification of LPMOs and the striking synergistic effect of fungal LPMOs when combined with canonical cellulases was discovered when fractions of fungal secretomes were evaluated in industrially relevant enzyme performance assays. Today, LPMOs are a central component in the Cellic CTec enzyme products which are used in several large-scale plants for the industrial production of lignocellulosic ethanol. LPMOs are characterized by an N-terminal histidine residue which, together with an internal histidine and a tyrosine residue, co-ordinates a single copper atom in a so-called histidine brace. The mechanism by which oxygen binds to the reduced copper atom has been reported and the general mechanism of copper-oxygen-mediated activation of carbon is being investigated in the light of these discoveries. LPMOs are widespread in both the fungal and the bacterial kingdoms, although the range of action of these enzymes remains to be elucidated. However, based on the high abundance of LPMOs expressed by microbes involved in the decomposition of organic matter, the importance of LPMOs in the natural carbon-cycle is predicted to be significant. In addition, it has been suggested that LPMOs play a role in the pathology of infectious diseases such as cholera and to thus be relevant in the field of medicine. © 2016 Authors; published by Portland Press Limited.

  10. OVERVIEW OF MONO-ENERGETIC GAMMA-RAY SOURCES & APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Hartemann, F V; Albert, F; Anderson, G G; Anderson, S G; Bayramian, A J; Betts, S M; Chu, T S; Cross, R R; Ebbers, C A; Fisher, S E; Gibson, D J; Ladran, A S; Marsh, R A; Messerly, M J; O' Neill, K L; Semenov, V A; Shverdin, M Y; Siders, C W; McNabb, D P; Barty, C P; Vlieks, A E; Jongewaard, E N; Tantawi, S G; Raubenheimer, T O

    2010-05-18

    Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable gamma-ray light sources based on Compton scattering between a high-brightness, relativistic electron beam and a high intensity laser pulse produced via chirped-pulse amplification (CPA). A precision, tunable Mono-Energetic Gamma-ray (MEGa-ray) source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC NAL will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energy range via Compton scattering. This MEGa-ray source will be used to excite nuclear resonance fluorescence in various isotopes. Applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. The source design, key parameters, and current status are presented, along with important applications, including nuclear resonance fluorescence. In conclusion, we have optimized the design of a high brightness Compton scattering gamma-ray source, specifically designed for NRF applications. Two different parameters sets have been considered: one where the number of photons scattered in a single shot reaches approximately 7.5 x 10{sup 8}, with a focal spot size around 8 {micro}m; in the second set, the spectral brightness is optimized by using a 20 {micro}m spot size, with 0.2% relative bandwidth.

  11. Assessing Ecological Impact Assessment: Lessons from Mono Lake, California.

    Science.gov (United States)

    Wiens, John A; Patten, Duncan T; Botkin, Daniel B

    1993-11-01

    Because of its high salinity and alkalinity, Mono Lake, in eastern California (USA), is a relatively simple ecosystem. It has become the focus of an environmental controversy over the effects of 50 yr of diversions of water from tributary streams to supply water to Los Angeles. Diversions lowered the lake level, increased the salinity, changed the availability of aquatic habitats, and altered the configuration of the shoreline and of islands that support breeding colonies of gulls. We consider (1) how two independent panels of experts synthesized scientific information on the lake ecosystem to assess the environmental consequences of these changes, and (2) how the findings of these groups influenced policy decisions and how well subsequent changes in the lake matched expectations. Despite differences in composition and approach, the two panels reached generally similar conclusions. These conclusions have been a major component of legal activities and the development of management plans for the lake and basin ecosystem. Both panels concluded that, because of the simplicity of the lake ecosystem, ecological consequences of changes in lake level and salinity associated with continuing diversions were likely to be unusually clear-cut. At certain lake levels these changes would be expected to alter algal and invertebrate populations and the populations of aquatic birds that feed upon them or to disrupt breeding activities in gull colonies. Projections about when critical lake levels might be reached, however, have not been met. This is largely because stream flows into the lake have been altered from recent historic patterns by the cessation of water diversions due to governmental and legal actions (prompted in part by the panels' findings) and by a prolonged drought. These events illustrate the difficulty of projecting a timetable for environmental changes, even in simple and well-studied ecosystems.

  12. 泥页岩井壁稳定流固化耦合模型%A fluid-solid-chemistry coupling model for shale wellbore stability

    Institute of Scientific and Technical Information of China (English)

    王倩; 周英操; 王刚; 蒋宏伟; 刘玉石

    2012-01-01

    A fluid-solid-chemistry coupling model is built considering fluid flow and ion transmission induced by shale-drilling fluid system electrochemical potential osmosis, nonlinearity of flow and solute diffusion in shale-drilling fluid system, and solid deformation resulted from fluid flow and ion transmission. The model is used to compute the time-varying pore pressure, stress and damage index in formations around the wellbore of a well. The result shows that the pore pressure and stress are lower without consideration of the diffusion potential induced by ion selective character of shale membrane. The linear model overestimates the pore pressure and stress fields around the sidewall. The damage index reveals that collapse first occurs in formations near the wellbore, the caving pressure increases and changes obviously with time, the fracture pressure reduces but doesn't change significantly with time, and the drilling fluid density window narrows down with time.%考虑泥页岩-钻井液体系电化势渗透产生的流体流动和离子运移、泥页岩-钻井液体系中流体流动和溶质扩散过程的非线性、流体流动和离子运移对固体变形的影响,建立泥页岩井壁稳定流-固-化耦合模型.应用建立的模型计算实例井井眼周围地层随时间变化的孔隙压力、应力以及破坏指数.结果表明,若不考虑泥页岩膜离子选择性形成的扩散电势,计算的孔隙压力和应力偏小,而线性模型过高地预测了井壁周围的孔隙压力场和应力场.根据破坏指数可以看出,坍塌破坏首先发生在井壁附近地层,坍塌压力随时间延长增大且变化较明显,破裂压力随时间延长减小但变化不显著,钻井液密度窗口随时间变窄.

  13. Modeling the key factors that could influence the diffusion of CO2 from a wellbore blowout in the Ordos Basin, China.

    Science.gov (United States)

    Li, Qi; Shi, Hui; Yang, Duoxing; Wei, Xiaochen

    2016-11-26

    Carbon dioxide (CO2) blowout from a wellbore is regarded as a potential environment risk of a CO2 capture and storage (CCS) project. In this paper, an assumed blowout of a wellbore was examined for China's Shenhua CCS demonstration project. The significant factors that influenced the diffusion of CO2 were identified by using a response surface method with the Box-Behnken experiment design. The numerical simulations showed that the mass emission rate of CO2 from the source and the ambient wind speed have significant influence on the area of interest (the area of high CO2 concentration above 30,000 ppm). There is a strong positive correlation between the mass emission rate and the area of interest, but there is a strong negative correlation between the ambient wind speed and the area of interest. Several other variables have very little influence on the area of interest, e.g., the temperature of CO2, ambient temperature, relative humidity, and stability class values. Due to the weather conditions at the Shenhua CCS demonstration site at the time of the modeled CO2 blowout, the largest diffusion distance of CO2 in the downwind direction did not exceed 200 m along the centerline. When the ambient wind speed is in the range of 0.1-2.0 m/s and the mass emission rate is in the range of 60-120 kg/s, the range of the diffusion of CO2 is at the most dangerous level (i.e., almost all Grade Four marks in the risk matrix). Therefore, if the injection of CO2 takes place in a region that has relatively low perennial wind speed, special attention should be paid to the formulation of pre-planned, emergency measures in case there is a leakage accident. The proposed risk matrix that classifies and grades blowout risks can be used as a reference for the development of appropriate regulations. This work may offer some indicators in developing risk profiles and emergency responses for CO2 blowouts.

  14. Effect of Subgrains on the Performance of Mono-Like Crystalline Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Su Zhou

    2013-01-01

    Full Text Available The application of Czochralski (Cz monocrystalline silicon material in solar cells is limited by its high cost and serious light-induced degradation. The use of cast multicrystalline silicon is also hindered by its high dislocation densities and high surface reflectance after texturing. Mono-like crystalline silicon is a promising material because it has the advantages of both mono- and multicrystalline silicon. However, when mono-like wafers are made into cells, the efficiencies of a batch of wafers often fluctuate within a wide range of >1% (absolute. In this work, mono-like wafers are classified by a simple process and fabricated into laser doping selective emitter cells. The effect and mechanism of subgrains on the performance of mono-like crystalline silicon solar cells are studied. The results show that the efficiency of mono-like crystalline silicon solar cells significantly depends on material defects that appear as subgrains on an alkaline textured surface. These subgrains have an almost negligible effect on the optical performance, shunt resistance, and junction recombination but significantly affect the minority carrier diffusion length and quantum efficiency within a long wavelength range. Finally, an average efficiency of 18.2% is achieved on wafers with hardly any subgrain but with a small-grain band.

  15. Analysis of Gear Wheel-shaft Joint Characterized by Comparable Pitch Diameter and Mounting Diameter

    Directory of Open Access Journals (Sweden)

    J. Ryś

    2003-01-01

    Full Text Available This paper presents the design procedure for a gear wheel-shaft direct frictional joint. The small difference between the operating pitch diameter of the gear and the mounting diameter of the frictional joint is the key feature of the connection. The contact surface of the frictional joint must be placed outside the bottom land of the gear, and the geometry of the joint is limited to the specific type of solutions.The strength analysis is based on the relation between the torque and statistical load intensity of the gear transmission. Several dimensionless parameters are introduced to simplify the calculations. Stress-strain verifying analysis with respect to combined loading, the condition of appropriate load-carrying capacity of the frictional joint and the fatigue strength of the shaft are applied to obtain the relations between the dimensions of the joint and other parameters. The final engineering solution may then be suggested. The approach is illustrated by a numerical example.The proposed procedure can be useful in design projects for small, high-powered modern reducers and new-generation geared motors, in particular when manufactured in various series of types.

  16. Effect of Adsorbent Diameter on the Performance of Adsorption Refrigeration

    Institute of Scientific and Technical Information of China (English)

    黄宏宇; 何兆红; 袁浩然; 小林敬幸; 赵丹丹; 窪田光宏; 郭华芳

    2014-01-01

    Adsorbents are important components in adsorption refrigeration. The diameter of an adsorbent can af-fect the heat and mass transfer of an adsorber. The effect of particle diameter on effective thermal conductivity was investigated. The heat transfer coefficient of the refrigerant and the void rate of the adsorbent layer can also affect the effective thermal conductivity of adsorbents. The performance of mass transfer in the adsorber is better when pressure drop decreases. Pressure drop decreases with increasing permeability. The permeability of the adsorbent layer can be improved with increasing adsorbent diameter. The effect of adsorbent diameter on refrigeration output power was experimentally studied. Output power initially increases and then decreases with increasing diameter under different cycle time conditions. Output power increases with decreasing cycle time under similar diameters.

  17. Topical report on subsurface fracture mapping from geothermal wellbores. Phase I. Pulsed radar techniques. Phase II. Conventional logging methods. Phase III. Magnetic borehole ranging

    Energy Technology Data Exchange (ETDEWEB)

    Hartenbaum, B.A.; Rawson, G.

    1980-09-01

    To advance the state-of-the-art in Hot Dry Rock technology, an evaluation is made of (i) the use of radar to map far-field fractures, (ii) the use of more than twenty different conventional well logging tools to map borehole-fracture intercepts, and (iii) the use of magnetic dipole ranging to determine the relative positions of the injection well and the production well within the fractured zone. It is found that according to calculations, VHF backscatter radar has the potential for mapping fractures within a distance of 50 +- 20 meters from the wellbore. A new technique for improving fracture identification is presented. Analyses of extant data indicate that when used synergistically the (1) caliper, (2) resistivity dipmeter, (3) televiewer, (4) television, (5) impression packer, and (6) acoustic transmission are useful for mapping borehole-fracture intercepts. Improvements in both data interpretation techniques and high temperature operation are required. The surveying of one borehole from another appears feasible at ranges of up to 200 to 500 meters by using a low frequency magnetic field generated by a moderately strong dipole source (a solenoid) located in one borehole, a sensitive B field detector that traverses part of the second borehole, narrow band filtering, and special data inversion techniques.

  18. On super edge-graceful trees of diameter four

    CERN Document Server

    Krop, E; Raridan, C

    2011-01-01

    In "On the super edge graceful trees of even orders," Chung, Lee, Gao, and Schaffer posed the following problem: Characterize trees of diameter 4 which are super edge-graceful. In this paper, we provide super edge-graceful labelings for all caterpillars and even size lobsters of diameter 4 which permit such labelings. We also provide super edge-graceful labelings for several families of odd size lobsters of diameter 4.

  19. k-Diameter of Circulant Graph with Degree 3

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xian-di; LI Man-li

    2005-01-01

    Parameters k-distance and k-diameter are extension of the distance and the diameter in graph theory. In this paper, the k-distance dk (x,y) between the any vertices x andy is first obtained in a connected circulant graph G with order n (n is even) and degree 3 by removing some vertices from the neighbour set of the x. Then, the k-diameters of the connected circulant graphs with order n and degree 3 are given by using the k-diameter dk (x, y).

  20. Characterization of a Mono-Ellipsoidal Imaging Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Guesdon, C.; Alxneit, I.; Tschudi, H.R.; Wuillemin, D.; Brunner, Y.; Winkel, L.; Sturzenegger, M.

    2004-03-01

    An imaging furnace was built and tested for investigating chemical reactions that involve melts and the release of condensable gases. A key feature is the sample stage with a water-cooled sample support to avoid reaction of the sample with crucible material. A built-in hammer allows for freezing the high-temperature composition of the sample and a glass dome above the sample allows for experiments under defined atmospheres. Measured peak flux densities on samples with a diameter of 5 mm clearly exceed 500 Wcm{sub -2} producing sample temperatures of at least 2500 K. Cold experiments with a smoke source at the place of the sample as well as decomposition experiments with chalcocite (Cu{sub 2}S) proved that an appropriate gas flow through the dome keeps the dome free of condensates. (author)

  1. Mean particle diameters: from statistical definition to physical understanding

    NARCIS (Netherlands)

    Alderliesten, M.

    2008-01-01

    Mean particle diameters are important for the science of particulate systems. This thesis deals with a definition system for these mean diameters, called Moment-Ratio (M-R) definition system, and provides a general statistical and physical basis. Also, the current DIN/ISO definition system is discus

  2. Effect of flow rate on diameter of electrospun nanoporous fibers

    Directory of Open Access Journals (Sweden)

    Tang Xiao-Peng

    2014-01-01

    Full Text Available The effect of flow rate on the diameter of the charged jet in the electrospinning process is studied theoretically. The obtained theoretical results offer in-depth physical understanding and mechanism of nanoporous fibers. It also reveals that the morphology and diameter of nanoporous microspheres can be controlled by the flow rate.

  3. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical... acid, mono-C9-11-alkyl esters, sodium salts (PMN P-01-149; CAS No. 84501-49-5) is subject to reporting...

  4. DIRECT ETHOXYLATION OF GLYCEROL MONO OLEATE FROM PALM OIL DERIVATE AS A NOVEL NON-IONIC POLYMERIC SURFACTANT

    OpenAIRE

    2012-01-01

    The work investigates ethoxylation of glycerol mono oleate (GMO) performed in the presence of an alkaline catalyst. Glycerol mono oleate applied was derivated from Indonesian palm oil. The reaction was conducted with variation of Glycerol mono oleate : ethylene oxide ratio, temperature, and catalyst concentration. Forier Transform Infra Red (FTIR) and Nuclear Magnetic Resonance (NMR) analysis showed products with degrees of ethoxylation n=2 and n=3. FTIR analysis of products gave a new peak a...

  5. MAGNESIUM MONO POTASSIUM PHOSPHATE GROUT FOR P-REACTOR VESSEL IN-SITU DECOMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Stefanko, D.

    2011-01-05

    The objective of this report is to document laboratory testing of magnesium mono potassium phosphate grouts for P-Reactor vessel in-situ decommissioning. Magnesium mono potassium phosphate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout (pH of about 12.4). A less alkaline material ({<=} 10.5) was desired to address a potential materials compatibility issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere. Fresh and cured properties were measured for: (1) commercially blended magnesium mono potassium phosphate packaged grouts, (2) commercially available binders blended with inert fillers at SRNL, (3) grouts prepared from technical grade MgO and KH{sub 2}PO{sub 4} and inert fillers (quartz sands, Class F fly ash), and (4) Ceramicrete{reg_sign} magnesium mono potassium phosphate-based grouts prepared at Argonne National Laboratory. Boric acid was evaluated as a set retarder in the magnesium mono potassium phosphate mixes.

  6. High resolution seismic reflection profiles of Holocene volcanic and tectonic features, Mono Lake, California

    Science.gov (United States)

    Jayko, A. S.; Hart, P. E.; Bursik, M. I.; McClain, J. S.; Moore, J. C.; Boyle, M.; Childs, J. R.; Novick, M.; Hill, D. P.; Mangan, M.; Roeske, S.

    2009-12-01

    The Inyo-Mono Craters of Long Valley and Mono Basin, California are the youngest eruptive vents of the Great Basin, USA and the second youngest in California. They are one of two seismically active volcanic centers with geothermal power production in the Walker Lane, western Great Basin, the other being the Coso Volcanic Field to the south. High resolution seismic reflection data collected from the northern tip of the Mono Craters eruptive centers in Mono Lake delinates two structural zones proximal to the active volcanic centers in Mono Lake. A growth structure drapped by ~30 m or more of bedded sediment shows increasing deformation and offset of clastic deposits on the northwest margin of the basin. Coherent thin-bedded stratigraphic sections with strong reflectors to 30-100m depth are preserved on the western and northern margins of the basin. The southern and southeastern areas of the lake are generally seismically opaque, due to extensive ash and tephra deposits as well as widespread methane. Thin pockets of well-bedded, poorly consolidated sediment of probable Holocene and last glacial age are present within intrabasin depressions providing some local age constraints on surfaces adjacent to volcanic vents and volcanically modified features.

  7. Review of the recording and age of the Mono Lake Excursion

    Science.gov (United States)

    Coe, R.; Liddicoat, J.

    2009-04-01

    Among the brief departures from gradual, long-term behaviour of the palaeomagnetic field in the Brunhes Normal Chron that reached opposite polarity or have a Virtual Geomagnetic Pole deep in the southern hemisphere, the first to be reported is the Laschamp Excursion (LE) in volcanic rocks in the Massif Central in France (Bonhommet and Zahringer, 1969). They originally believed it occurred between about 9,000 to 20,000 years before present, but it is now assigned an age of about 40,000 years B.P. (Guillou et al., 2004). Denham and Cox (1971) unsuccessfully sought the LE in exposed lake sediments that seemed to span that interval in the Mono Basin in the western Great Basin of the U.S., but instead encountered anomalous field behaviour that is called the Mono Lake Excursion (MLE)(Liddicoat and Coe, 1979). As a tribute to Norbert Bonhommet, who assisted us in our initial field work in the Mono Basin and shared a long-standing interest in the LE and MLE, we will review the palaeomagnetic behaviour and age of the MLE in the Mono Basin and elsewhere, for which there are nearly 20 reports of its occurrence globally, and evaluate the recent suggestion that the excursion at Mono Lake and the LE are the same.

  8. Selective mono-radioiodination and characterization of a cell-penetrating peptide. L-Tyr-maurocalcine

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadi, Mitra; Bacot, Sandrine; Perret, Pascale; Riou, Laurent; Ghezzi, Catherine [Universite Joseph Fourier, Grenoble (France); INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Poillot, Cathy; Cestele, Sandrine [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Desruet, Marie-Dominique [INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Couvet, Morgane; Bourgoin, Sandrine; Seve, Michel [CRI-INSERM U823, Grenoble (France). Inst. of Albert Bonniot; Universite Joseph Fourier, Grenoble (France); Waard, Michel de [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Smartox Biotechnologies, Grenoble (France)

    2014-07-01

    Mono-and poly-iodinated peptides form frequently during radioiodination procedures. However, the formation of a single species in its mono-iodinated form is essential for quantitative studies such as determination of tissue concentration or image quantification. Therefore, the aim of the present study was to define the optimal experimental conditions in order to exclusively obtain the mono-iodinated form of L-maurocalcine (L-MCa). L-MCa is an animal venom toxin which was shown to act as a cell-penetrating peptide. In order to apply the current direct radioiodination technique using oxidative agents including chloramine T, Iodo-Gen {sup registered} or lactoperoxidase, an analogue of this peptide containing a tyrosine residue (Tyr-L-MCa) was synthesized and was shown to fold/oxidize properly. The enzymatic approach using lactoperoxidase/H{sub 2}O{sub 2} was found to be the best method for radioiodination of Tyr-L-MCa. MALDI-TOF mass spectrometry analyses were then used for identification of the chromatographic eluting components of the reaction mixtures. We observed that the production of different radioiodinated species depended upon the reaction conditions. Our results successfully described the experimental conditions of peptide radioiodination allowing the exclusive production of the mono-iodinated form with high radiochemical purity and without the need for a purification step. Mono-radioiodination of L-Tyr-MCa will be crucial for future quantitative studies, investigating the mechanism of cell penetration and in vivo biodistribution.

  9. Reliable Diameter Control of Carbon Nanotube Nanobundles Using Withdrawal Velocity

    Science.gov (United States)

    Shin, Jung Hwal; Kim, Kanghyun; An, Taechang; Choi, WooSeok; Lim, Geunbae

    2016-09-01

    Carbon nanotube (CNT) nanobundles are widely used in nanoscale imaging, fabrication, and electrochemical and biological sensing. The diameter of CNT nanobundles should be controlled precisely, because it is an important factor in determining electrode performance. Here, we fabricated CNT nanobundles on tungsten tips using dielectrophoresis (DEP) force and controlled their diameters by varying the withdrawal velocity of the tungsten tips. Withdrawal velocity pulling away from the liquid-air interface could be an important, reliable parameter to control the diameter of CNT nanobundles. The withdrawal velocity was controlled automatically and precisely with a one-dimensional motorized stage. The effect of the withdrawal velocity on the diameter of CNT nanobundles was analyzed theoretically and compared with the experimental results. Based on the attachment efficiency, the withdrawal velocity is inversely proportional to the diameter of the CNT nanobundles; this has been demonstrated experimentally. Control of the withdrawal velocity will play an important role in fabricating CNT nanobundles using DEP phenomena.

  10. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  11. Superresolution measurement of nanofiber diameter by modes beating

    Science.gov (United States)

    Fenton, E. F.; Solano, P.; Hoffman, J. E.; Orozco, L. A.; Rolston, S. L.; Fatemi, F. K.

    2016-05-01

    Nanofibers are becoming an important tool in quantum information technologies for coupling photonics systems to atomic systems. Nondestructive techniques for characterizing these nanofibers prior to integration into an apparatus are desirable. In this work, we probe the light propagating in a fused silica optical nanofiber (750-nm-diameter) by coupling it evanescently to a 6- μm-diameter microfiber that is scanned along the nanofiber length. This technique is capable of observing all possible beat lengths among different propagating modes. The beat lengths are strongly dependent on the nanofiber diameter and refractive index of the fiber. The steep dependence has enabled measurements of the fiber diameter with sub-Angstrom sensitivity. The diameter extracted from the beat length measurements agrees with a measurement made using scanning electron microscopy. Work supported by NSF.

  12. Diameter of common bile duct: what are the predicting factors?

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2007-07-01

    Full Text Available

    BACKGROUND: This was a study to determine the correlation between the common bile duct (CBD diameter and demographic data, fasting, and the history of opium addiction.
    METHODS: This was a cross-sectional study on 375 patients (>16 years old including 219 females and 156 males. They had no evident hepatobiliary or pancreatic disease and underwent abdominopelvic ultrasonography for measurement of their CBD diameter. Ultrasound (US was performed to measure CBD diameter at the porta hepatis (proximal part and behind the head of the pancreas (distal part. Correlation coefficients for the association between CBD diameter and predictive factors were calculated. t-test was applied to compare the means between the groups.
    RESULTS: The mean CBD diameter (1 standard deviation, in proximal and distal parts were 3.64 mm (±1.2 and 3.72 mm (±1.2, respectively. The CBD diameters (proximal and distal were significantly (P<0.05 correlated with age (r = 0.55 and 0.54, respectively, BMI (r = 0.25 and 0.27, respectively and portal vein diameter (r = 0.24 and 0.22, respectively. Distal diameter of CBD was significantly larger in opium addicts (5.66 ± 2.65 in comparison with non addicts (3.68 ± 1.17, P = 0.04.
    CONCLUSIONS: CBD diameter associates with age, BMI, portal vein diameter and opium addiction. CBD dilatation, if it can not be explained by age, opium usage or large BMI, should be evaluated further to rule out obstruction.
    KEY WORDS: Common bile duct, predicting factors, ultrasonography.

  13. Regulation of TGF-β Superfamily Signaling by SMAD Mono-Ubiquitination

    Directory of Open Access Journals (Sweden)

    Feng Xie

    2014-10-01

    Full Text Available TGF-β(transforming growth factor-β superfamily signaling mediators are important regulators of diverse physiological and pathological events. TGF-β signals are transduced by transmembrane type I and type II serine/threonine kinase receptors and their downstream effectors, the SMAD(drosophila mothers against decapentaplegic protein proteins. Numerous studies have already demonstrated crucial regulatory roles for modification of TGF-β pathway components by poly-ubiquitination. Recently, several studies also uncovered mono-ubiquitination of SMADs as a mechanism for SMAD activation or inactivation. Mono-ubiquitination and subsequent deubiquitination of SMAD proteins accordingly play important roles in the control of TGF-β superfamily signaling. This review highlights the major pathways regulated by SMAD mono-ubiquitination.

  14. Mono-X Versus Direct Searches: Simplified Models for Dark Matter at the LHC

    CERN Document Server

    Liew, Seng Pei; Vichi, Alessandro; Zurek, Kathryn M

    2016-01-01

    We consider simplified models for dark matter (DM) at the LHC, focused on mono-Higgs, -Z, -W or -b produced in the final state. Our primary purpose is to study the LHC reach of a relatively complete set of simplified models for these final states, while comparing the reach of the mono-X DM search against direct searches for the mediating particle. We find that direct searches for the mediating particle, whether in di-jets, jets+MET, multi-b+MET, or di-boson+MET, are usually stronger. We draw attention to the cases that the mono-X search is strongest, which include regions of parameter space in inelastic DM, two Higgs doublet, and squark mediated production models with a compressed spectrum.

  15. Impact of temperature on performance of series and parallel connected mono-crystalline silicon solar cells

    Directory of Open Access Journals (Sweden)

    Subhash Chander

    2015-11-01

    Full Text Available This paper presents a study on impact of temperature on the performance of series and parallel connected mono-crystalline silicon (mono-Si solar cell employing solar simulator. The experiment was carried out at constant light intensity 550 W/m2with cell temperature in the range 25–60 oC for single, series and parallel connected mono-Si solar cells. The performance parameters like open circuit voltage, maximum power, fill factor and efficiency are found to decrease with cell temperature while the short circuit current is observed to increase. The experimental results reveal that silicon solar cells connected in series and parallel combinations follow the Kirchhoff’s laws and the temperature has a significant effect on the performance parameters of solar cell.

  16. Second- and third-order nonlinear optical properties of unsubstituted and mono-substituted chalcones

    Science.gov (United States)

    Abegão, Luis M. G.; Fonseca, Ruben D.; Santos, Francisco A.; Souza, Gabriela B.; Barreiros, André Luis B. S.; Barreiros, Marizeth L.; Alencar, M. A. R. C.; Mendonça, Cleber R.; Silva, Daniel L.; De Boni, Leonardo; Rodrigues, J. J.

    2016-03-01

    This work describes the second and third orders of nonlinear optics properties of unsubstituted chalcone (C15H12O) and mono-substituted chalcone (C16H14O2) in solution, using hyper-Rayleigh scattering and Z-Scan techniques to determine the first molecular hyperpolarizability (β) and the two-photon absorption (2PA) cross section respectively. β Values of 25.4 × 10-30 esu and 31.6 × 10-30 esu, for unsubstituted and mono-substituted chalcone, respectively, dissolved in methanol have been obtained. The highest values of 2PA cross-sections obtained were 9 GM and 14 GM for unsubstituted and mono-substituted chalcone, respectively. The experimental 2PA cross sections obtained for each chalcone are in good agreement with theoretical results.

  17. Hydraulic fracturing and wellbore completion of coalbed methane wells in the Powder River Basin, Wyoming: Implications for water and gas production

    Energy Technology Data Exchange (ETDEWEB)

    Colmenares, L.B.; Zoback, M.D. [Stanford University, Stanford, CA (United States). Dept. of Geophysics

    2007-01-15

    Excessive water production (more than 7000 bbl/month per well) from many coalbed methane (CBM) wells in the Powder River Basin of Wyoming is also associated with significant delays in the time it takes for gas production to begin. Analysis of about 550 water-enhancement activities carried out during well completion demonstrates that such activities result in hydraulic fracturing of the coal. Water-enhancement activities, consists of pumping 60 bbl of water/min into the coal seam during approximately 15 min. This is done to clean the well-bore and to enhance CBM production. Hydraulic fracturing is of concern because vertical hydraulic fracture growth could extend into adjacent formations and potentially result in excess CBM water production and inefficient depressurization of coals. Analysis of the pressure-time records of the water-enhancement tests enabled us to determine the magnitude of the least principal stress (S{sub 3}) in the coal seams of 372 wells. These data reveal that because S{sub 3} switches between the minimum horizontal stress and the overburden at different locations, both vertical and horizontal hydraulic fracture growth is inferred to occur in the basin, depending on the exact location and coal layer. Relatively low water production is observed for wells with inferred horizontal fractures, whereas all of the wells associated with excessive water production are characterized by inferred vertical hydraulic fractures. The reason wells with exceptionally high water production show delays in gas production appears to be inefficient depressurization of the coal caused by water production from the formations outside the coal. To minimize CBM water production, we recommend that in areas of known vertical fracture propagation, the injection rate during the water-enhancement tests should be reduced to prevent the propagation of induced fractures into adjacent water-bearing formations.

  18. Association between axial length and horizontal and vertical globe diameters.

    Science.gov (United States)

    Jonas, Jost B; Ohno-Matsui, Kyoko; Holbach, Leonard; Panda-Jonas, Songhomitra

    2017-02-01

    To assess relationships between axial length and the horizontal and vertical globe diameters. The study consisted of enucleated human eyes. The horizontal, vertical, and sagittal diameters were measured. The study included 135 globes removed because of malignant uveal melanoma (111 globes) or end-stage painful glaucoma (n = 24 eyes). Mean axial, horizontal, and vertical diameters were 24.6 ± 2.6 mm (range: 20-35 mm), 23.7 ± 1.4 mm (range: 21-29 mm) and 23.7 ± 1.4 mm (range: 20-29 mm) respectively. The horizontal diameter and vertical diameter did not differ significantly (P = 0.92), while both were significantly (P globe diameter (P globe diameter = 0.84 × horizontal globe diameter + 3.69). The axial diameter was significantly (P 24 mm, the horizontal and vertical globe diameter increased by a lower amount of 0.19 and 0.21 mm, respectively, for each mm increase in axial diameter. Myopic enlargement of the globe beyond an axial length of 24 mm takes place predominantly in the sagittal axis, leading to a change in the globe form from a sphere to an elongated form. It fits with the notion that myopic elongation may occur by an elongation of the eye walls in regions close to the globe's equator.

  19. Aza-Michael Mono-addition Using Acidic Alumina under Solventless Conditions

    Directory of Open Access Journals (Sweden)

    Giovanna Bosica

    2016-06-01

    Full Text Available Aza-Michael reactions between primary aliphatic and aromatic amines and various Michael acceptors have been performed under environmentally-friendly solventless conditions using acidic alumina as a heterogeneous catalyst to selectively obtain the corresponding mono-adducts in high yields. Ethyl acrylate was the main acceptor used, although others such as acrylonitrile, methyl acrylate and acrylamide were also utilized successfully. Bi-functional amines also gave the mono-adducts in good to excellent yields. Such compounds can serve as intermediates for the synthesis of anti-cancer and antibiotic drugs.

  20. A study on synthesis and oxidation mechanism of mono-alkyl phosphate

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Oxidation of white phosphorus by peroxides to produce mono-alkyl phosphate in the alcoholic solution has been studied under non-and catalytic conditions. In this paper,the mechanism of the oxidation process was analyzed. The content of mono-alkyl phosphate in the product is affected by different types of alcoholic solution and peroxide solvent. The result shows the availability of the following order for the activity of the peroxide solvent and alcoholic solutions-tert-butyl hydroperoxide>(di) benzoyl perox...

  1. Extracting the complex optical conductivity of mono- and bilayer graphene by ellipsometry

    Science.gov (United States)

    Chang, You-Chia; Liu, Chang-Hua; Liu, Che-Hung; Zhong, Zhaohui; Norris, Theodore B.

    2014-06-01

    A method for analysis of spectroscopic ellipsometry data is demonstrated to extract the optical conductivity of mono- and bilayer chemical-vapor-deposited graphene. We model graphene as a truly two-dimensional (2D) material with a sheet conductivity, rather than a phenomenological effective refractive index as has been used in the literature. This technique measures both the real and imaginary part of the optical conductivity, which is important for graphene optoelectronics and metamaterials. Using this method, we obtain broadband measurements of the complex optical conductivity for mono- and bilayer graphene from ultraviolet to mid-infrared wavelengths. We also study how chemical doping with nitric acid modifies the complex optical conductivity.

  2. Ultrasonication of pyrogenic microorganisms improves the detection of pyrogens in the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    of the assay. The interleukin-6 inducing capacity of a broad spectrum of UV-killed and ultrasonicated microorganisms is examined in Mono Mac 6 cells. The interleukin-6 secretion is determined in a sandwich immunoassay (DELFIA). The Mono Mac 6 assay is able to detect UV-killed Bacillus subtilis, Staphylococcus...... aureus and Salmonella typhimurium, but neither Candida albicans nor Aspergillus niger. After ultrasonication of the microorganisms it is possible to detect C. albicans and A. niger. The interleukin-6 inducing ability of the examined microorganisms is in no case reduced after ultrasonic treatment. However...

  3. Diameter-dependent thermodynamic and elastic properties of metallic nanoparticles

    Science.gov (United States)

    Chandra, Jeewan; Kholiya, Kuldeep

    2015-04-01

    A simple theoretical model has been proposed to study the diameter-dependent properties of metallic nanoparticles, i.e. Ag, Au, Al, Ni, Pb, Cu and Fe. The diameter-dependent thermodynamic properties includes melting temperature, Debye temperature, evaporation temperature, melting enthapy and melting entropy. The model is also extended to study the diameter-dependent elastic properties including bulk modulus, Young's modulus and thermal expansion coefficient. On comparison with available experimental findings and other theoretical approaches, the results obtained with the present formulation depict a close agreement and demonstrate the validity of the method proposed in the present paper.

  4. Measurement of fetal biparietal diameter in owl monkeys (Aotus nancymaae).

    Science.gov (United States)

    Schuler, A Michele; Brady, Alan G; Tustin, George W; Parks, Virginia L; Morris, Chris G; Abee, Christian R

    2010-09-01

    Owl monkeys are New World primates frequently used in biomedical research. Despite the historical difficulty of breeding owl monkeys in captivity, several productive owl monkey breeding colonies exist currently. The animals in the colony we describe here are not timed-pregnant, and determination of gestational age is an important factor in prenatal care. Gestational age of human fetuses is often determined by using transabdominal measurements of fetal biparietal diameter. The purpose of this study was to correlate biparietal diameter measurements with gestational age in owl monkeys. We found that biparietal diameter can be used to accurately predict gestational age in owl monkeys.

  5. The Non-Homologous Nature of Solar Diameter Variations

    CERN Document Server

    Sofia, S; Demarque, P; Li, L; Thuillier, G; Sofia, Sabatino; Basu, Sarbani; Demarque, Pierre; Li, Linghuai; Thuillier, Gerard

    2005-01-01

    We show in this paper that the changes of the solar diameter in response to variations of large scale magnetic fields and turbulence are not homologous. For the best current model, the variation at the photospheric level is over 1000 times larger than the variation at a depth of 5 Mm, which is about the level at which f-mode solar oscillations determine diameter variations. This model is supported by observations that indicate larger diameter changes for high degree f-modes than for low degree f-modes, since energy of the former are concentrated at shallower layers than the latter.

  6. Tool electrode wear in electrical discharge of small diameter holes

    Directory of Open Access Journals (Sweden)

    Slătineanu Laurenţiu

    2017-01-01

    Full Text Available In the paper, the problem of obtaining small diameter holes in workpieces made of high speed steel by electrical discharge machining was formulated. A fulfil factorial experiment was designed and materialized, taking into consideration the tool electrode diameter, pulse on time and pulse off time as independent variables. The tool electrode wear was evaluated by means of the decrease of tool electrode mass and length. On the base of experimental results, power type empirical mathematical models were determined. One noticed the higher influence exerted by the too electrode diameter, whose increase determine the decrease of the tool electrode.

  7. Relationship of rolling bearing stiffness with diameter of roller

    Institute of Scientific and Technical Information of China (English)

    郭茂林; 王刚; 张瑞

    2002-01-01

    The theoretical formula of roller bearing stiffness is induced and compared with its empirical formula.In the experience formula the stiffness of roller bearing has nothing to do with the roller diameter. The relation-ship of roller bearing stiffness with roller diameter was studied using Hz contacting theory. It is concluded thatconclusion in experience formula is only approximate result of data processing under special conditions, and therelation between stiffness of roller bearing and roller diameter must be taken into consideration while designingor selecting roller bearings.

  8. Porosity Assessment for Different Diameters of Coir Lignocellulosic Fibers

    Science.gov (United States)

    da Luz, Fernanda Santos; Paciornik, Sidnei; Monteiro, Sergio Neves; da Silva, Luiz Carlos; Tommasini, Flávio James; Candido, Verônica Scarpini

    2017-08-01

    The application of natural lignocellulosic fibers (LCFs) in engineering composites has increased interest in their properties and structural characteristics. In particular, the inherent porosity of an LCF markedly affects its density and the adhesion to polymer matrices. For the first time, both open and closed porosities of a natural LCF, for different diameter ranges, were assessed. Fibers extracted from the mesocarp of the coconut fruit were investigated by nondestructive methods of density measurements and x-ray microtomography (microCT). It was found that, for all diameter ranges, the closed porosity is significantly higher than the open porosity. The total porosity increases with diameter to around 60% for coir fibers with more than 503 μm in diameter. The amount and characteristics of these open and closed porosities were revealed by t test and Weibull statistics as well as by microCT.

  9. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...

  10. Study of Linearly Polarized Light Measuring Fiber Diameter

    Energy Technology Data Exchange (ETDEWEB)

    Liang Hong, E-mail: lianghong@cuc.edu.cn [School of science, Communication University of China 100024 (China)

    2011-02-01

    The letter discusses a new way to measure fiber diameters, studies the theory of measuring fiber radius using this way, carries out numerical simulation based on this and provides experiment method as well.

  11. Eddy sensors for small diameter stainless steel tubes.

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  12. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    of up-to-date facilities has been: Equipment for controlling centrifuge tests, data acquisition, preparation of test samples and equipment for and making of lateral load tests. The present research has been narrowed to investigate the static and cyclic behaviour of stiff piles with a diameter of 1-3 m...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles....... Comparison of the different approaches shows some discrepancy and conflicting statements, but the main findings can be summarized as: • The standard p-y curves are inadequate to describe the behaviour of lateral loaded large diameter rigid piles. • Initial stiffness of the p-y curves is depended...

  13. Pupil diameter reflects uncertainty in attentional selection during visual search

    Directory of Open Access Journals (Sweden)

    Joy J. Geng

    2015-08-01

    Full Text Available Pupil diameter has long been used as a metric of cognitive processing. However, recent advances suggest that the cognitive sources of change in pupil size may reflect LC-NE function and the calculation of unexpected uncertainty in decision processes (Aston-Jones & Cohen, 2005b; Yu & Dayan, 2005. In the current experiments, we explored the role of uncertainty in attentional selection on task-evoked changes in pupil diameter during visual search. We found that task-evoked changes in pupil diameter were related to uncertainty during attentional selection as measured by reaction time and performance accuracy (Experiments 1-2. Control analyses demonstrated that the results are unlikely to be due to error monitoring or response uncertainty. Our results suggest that pupil diameter can be used as an implicit metric of uncertainty in ongoing attentional selection requiring effortful control processes.

  14. Is ultrasonographically detected nodule diameter concordant with pathological tumor size?

    Science.gov (United States)

    Bilginer, Muhammet Cuneyt; Ozdemir, Didem; Baser, Husniye; Dogan, Hayriye Tatli; Yalcin, Abdussamed; Ersoy, Reyhan; Cakir, Bekir

    2017-06-01

    We aimed to compare preoperative ultrasonographical and postoperative histopathological diameters of differentiated thyroid cancer (DTC) lesions and investigate possible factors that can predict the discordance between two measurements. Data of patients with histopathologically confirmed DTC were reviewed retrospectively. Nodules evaluated by preoperative US were matched with histopathologically examined nodules. Incidental tumors and nodules that can not be matched in US and histopathology reports were excluded. Preoperative US diameter and postoperative histopathological size were compared and percentage difference between two measurements was calculated for each lesion. There were 607 DTC foci in 562 patients. Mean US diameter was significantly higher than histopathological diameter (21.0 ± 15.6 mm vs 17.3 ± 13.6, p size in 444 (73.1%), equal in 15 (2.5%) and lower in 148 (24.4%) nodules. Marginal irregularity was observed in 253 (57%) lesions with US diameter > tumor size and 108 (73%) lesions with US diameter size (p = 0.010). Rate of nodules with peripheral halo was higher in lesions with US diameter > tumor size (30.6% vs 20.3%, p = 0.015). In nodules with US diameter > tumor size, percentage difference was lower in nodules with microcalcification (p = 0.020) and higher in cytologically benign nodules (p size, size in a considerable ratio of DTCs. It might be helpful to consider this discordance while deciding surgical extent in these patients. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  15. Minimum Orders of Eulerian Oriented Digraphs with Given Diameter

    Institute of Scientific and Technical Information of China (English)

    Yoomi RHO; Byeong Moon KIM; Woonjae HWANG; Byung Chul SONG

    2014-01-01

    A digraph D is oriented if it does not contain 2-cycles. If an oriented digraph D has a directed eulerian path, it is an oriented eulerian digraph. In this paper, when an oriented eulerian digraph D has minimum out-degree 2 and a diameter d, we find the minimum order of D. In addition, when D is 2-regular with diameter 4m (m≥2), we classify the extremal cases.

  16. Catalytic growth of carbon nanotubes with large inner diameters

    Directory of Open Access Journals (Sweden)

    WEI REN ZHONG

    2005-02-01

    Full Text Available Carbon nanotubes (2.4 g/g catalyst, with large inner diameters were successfully synthesized through pyrolysis of methane on a Ni–Cu–Al catalyst by adding sodium carbonate into the carbon nanotubes growth system. The inner diameter of the carbon nanotubes prepared by this method is about 20–60 nm, while their outer diameter is about 40–80 nm. Transmission electron microscopy and X-ray diffraction were employed to investigate the morphology and microstructures of the carbon nanotubes. The analyses showed that these carbon nanotubes have large inner diameters and good graphitization. The addition of sodium carbonate into the reaction system brings about a slight decrease in the methane conversion and the yield of carbon. The experimental results showed that sodium carbonate is a mildly toxic material which influenced the catalytic activity of the Ni–Cu–Al catalyst and resulted in the formation of carbon nanotubes with large inner diameters. The growth mechanism of the carbon nanotubes with large inner diameters is discussed in this paper.

  17. Diameter dependence of thermoelectric power of semiconducting carbon nanotubes

    Science.gov (United States)

    Hung, Nguyen T.; Nugraha, Ahmad R. T.; Hasdeo, Eddwi H.; Dresselhaus, Mildred S.; Saito, Riichiro

    2015-10-01

    We calculate the thermoelectric power (or thermopower) of many semiconducting single wall carbon nanotubes (s-SWNTs) within a diameter range 0.5 -1.5 nm by using the Boltzmann transport formalism combined with an extended tight-binding model. We find that the thermopower of s-SWNTs increases as the tube diameter decreases. For some s-SWNTs with diameters less than 0.6 nm , the thermopower can reach a value larger than 2000 μ V /K at room temperature, which is about 6 to 10 times larger than that found in commonly used thermoelectric materials. The large thermopower values may be attributed to the one dimensionality of the nanotubes and to the presence of large band gaps of the small-diameter s-SWNTs. We derive an analytical formula to reproduce the numerical calculation of the thermopower and we find that the thermopower of a given s-SWNT is directly related with its band gap. The formula also explains the shape of the thermopower as a function of tube diameter, which looks similar to the shape of the so-called Kataura plot of the band gap dependence on tube diameter.

  18. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Science.gov (United States)

    2010-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  19. Polyurethane triblock copolymers with mono-disperse hard segments. Influence of the hard segment length on thermal and thermomechanical properties

    NARCIS (Netherlands)

    Arun, Araichimani; Baack, Kasper K.J.; Gaymans, Reinoud J.

    2008-01-01

    Polyurethane triblock copolymers were synthesized by reacting 4,4-methylenebis(phenyl isocyanate) (MDI)-endcapped poly(tetramethylene oxide) (PTMO) with mono-amine-amide (MMA) units. Four different MMA units were used, i.e. no-amide (6m), mono-amide (6B), di-amide (6T6m) and tri-amide (6T6B), based

  20. Synthesis of lanthanum tris (mono-i-octyl phthalate)and its thermal stability for polyvinyl chloride

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel type of thermal stabilizer-lanthanum tris (mono-i-octyl phthalate) (LTMP) was synthesized by double-decomposition reaction of sodium mono-i-octyl phthalate with lanthanum chloride at 60℃.Sodium mono-i-octyl phthalate was prepared by sodium hydrate and mono-i-octyl phthalate prepared by reaction of isooctyl alcohol and phthalic anhydride in the presence of sulfuric acid catalyst at 110 ℃. The yield of lanthanum tris (mono-i-octyl phthalate) is about 84.5%. Its thermal stabilities were measured by heat-ageing oven test when incorporated into PVC. The experimental results show that the heat stability time is about 40min at 190 ℃ when adding 3phr (per hundred resin) to PVC. The thermal stability of this product is better than that of Ca-Zn complex and basic lead salt stabilizers, and equal to that of dibutyltin dilaurate.

  1. Health Disparities and Relational Well-Being between Multi- and Mono-Ethnic Asian Americans

    Science.gov (United States)

    Zhang, Wei

    2013-01-01

    Focusing on Hawaii, a state with 21.3% of the population being multi-racial according to the 2010 U.S. Census, this study aims to examine the existence and nature of health disparities between mono- and multi-ethnic Asian Americans and the importance of Relational Well-Being in affecting the health of Asian Americans. A series of ordinary least…

  2. De kwalitatieve en semikwantitatieve bepaling van 6-mono-acetylmorfine in de urine van druggebruikers (I)

    NARCIS (Netherlands)

    Derks HJGM; van Twillert K; Zomer G

    1984-01-01

    In dit rapport wordt een analytische methode beschreven voor de bepaling van 6-mono-acetylmorfine in urine. Deze metaboliet van heroine is een marker voor heroine-gebruik en de bepaling ervan kan gebruikt worden om het gebruik van heroine van dat van morfine te onderscheiden. De methode is gebasee

  3. Synthesis and photochromic behavior of mono-,and biphotochromic system linked by p-phenylene bridge

    Institute of Scientific and Technical Information of China (English)

    N.O.Mahmoodi; K.Tabatabaeian; A.Ghavidast

    2010-01-01

    The synthesis of mono- and bis-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer,which behave as photochromic materials,is reported.The structure-photochromic behavior relationship (SPBR) of the synthesized compounds has been analyzed.

  4. Literature review on cyclic lateral loading effects of mono-bucket foundations

    DEFF Research Database (Denmark)

    Kapitanov, Lachezar Rosenov; Duroska, Peter; Quirante, Cesar Antonio Garcia

    2016-01-01

    calculation is highly demanded at the different design phases. The intention of the current study is to present, review and summarize the existing techniques to assess the effect of cyclic loading on Mono-Bucket foundations while emphasizing the advantage and disadvantage of each of them. Additionally...

  5. Synthesis of Versatile Building Blocks through Asymmetric Hydrogenation of Functionalized Itaconic Acid Mono-Esters

    NARCIS (Netherlands)

    Hekking, Koen F.W.; Lefort, Laurent; Vries, André H.M. de; Delft, Floris L. van; Schoemaker, Hans E.; Vries, Johannes G. de; Rutjes, Floris P.J.T.

    2008-01-01

    The rhodium-catalyzed asymmetric hydrogenation of several β-substituted itaconic acid mono-esters, using a library of monodentate phosphoramidite and phosphite ligands is described. Two β-alkyl-substituted substrates were readily hydrogenated by the rhodium complex Rh(COD)2BF4 in combination with (S

  6. Upgrading of the Mono Media Filters in Water Treatment Plants by Changing Filter Media

    Directory of Open Access Journals (Sweden)

    L Rezaei

    2011-01-01

    Full Text Available "n "n "nBackground and Objectives:Dual media filters have two different layer beds consist of sand and Anthracite. Advantage of dual media filters is longer run duration and more filtration rate. The purpose of this study was to achieve a performable model to improve single media Filters in water treatment plants."nMaterials and Methods: in this cross-sectional study, two pilots; mono and dual media were made and in a 5 month period samples taking were done. Total samples taken from input and output of each pilot, was 40. The samples then introduced for the measurment of turbidity and total organic carbon. Meanwhile the filters head loss also quantified in 40 times head loss measurement was done."nResults: Average turbidity removal in mono and two layer pilots were 63 and 65 percent respectively. Average removal of Total Organic Carbon in mono and two media pilots were 40 and 66 percent respectively. Head loss in dual and single media pilots were 0 .68 and 1.15 m respectively."nConclusion: Although average torbidity removal disparity between two pilots was not significant the amount of total organic carbon removed was considerable. Average head loss in single media pilot was more than dual media type. Ratio of UFRV in dual media to mono media filter was 51:30 it shows that filtration rate capacity will be improved up to70 percent by changing media type.

  7. Preparation of mono- and diacetyl 4,4′-dimethylbiphenyl and their corresponding carboxylic acids

    DEFF Research Database (Denmark)

    Titinchi, Salam J.J.; Kamounah, Fadhil S.; Abbo, Hanna S.

    2007-01-01

    dimethylbiphenyls. In chloroalkane or carbon disulfide solvent, the yields of isomers were in the order: 2 -> 3-; in nitromethane 3-isomer predominated. On the other hand diacetylation of the hydrocarbon gave only the 2,3′-diacetyl isomer. The mono- and di-ketones are converted to the corresponding carboxylic acids...

  8. Synthesis of hierarchical zeolites using an inexpensive mono-quaternary ammonium surfactant as mesoporogen.

    Science.gov (United States)

    Zhu, Xiaochun; Rohling, Roderigh; Filonenko, Georgy; Mezari, Brahim; Hofmann, Jan P; Asahina, Shunsuke; Hensen, Emiel J M

    2014-12-04

    A simple amphiphilic surfactant containing a mono-quaternary ammonium head group (N-methylpiperidine) is effective in imparting substantial mesoporosity during synthesis of SSZ-13 and ZSM-5 zeolites. Highly mesoporous SSZ-13 prepared in this manner shows greatly improved catalytic performance in the methanol-to-olefins reaction compared to bulk SSZ-13.

  9. Experimental damping assessment of a full scale offshore mono bucket foundation

    DEFF Research Database (Denmark)

    Gres, Szymon; Fejerskov, Morten; Ibsen, Lars Bo

    2016-01-01

    This paper quantifies the system damping of a offshore meteorological mast supported by a Mono Bucket foundation based on a long-term experimental campaign. The structure is located at Dogger Bank west, North Sea, and equipped with a measurement system monitoring acceleration, strain, inclination...

  10. Forced vibration and wave propagation in mono-coupled periodic structures

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1986-01-01

    This paper describes the wave propagation and vibration characteristics of mono-coupled structures which are of spatially periodic nature. The receptance approach to periodic structure theory is applied to study undamped periodic systems with composite structural elements; particular emphasis...... of the determination of the junction-receptance. The influence of such a disorder is illustrated by a simple example...

  11. Emotions in freely varying and mono-pitched vowels, acoustic and EGG analyses.

    Science.gov (United States)

    Waaramaa, Teija; Palo, Pertti; Kankare, Elina

    2015-12-01

    Vocal emotions are expressed either by speech or singing. The difference is that in singing the pitch is predetermined while in speech it may vary freely. It was of interest to study whether there were voice quality differences between freely varying and mono-pitched vowels expressed by professional actors. Given their profession, actors have to be able to express emotions both by speech and singing. Electroglottogram and acoustic analyses of emotional utterances embedded in expressions of freely varying vowels [a:], [i:], [u:] (96 samples) and mono-pitched protracted vowels (96 samples) were studied. Contact quotient (CQEGG) was calculated using 35%, 55%, and 80% threshold levels. Three different threshold levels were used in order to evaluate their effects on emotions. Genders were studied separately. The results suggested significant gender differences for CQEGG 80% threshold level. SPL, CQEGG, and F4 were used to convey emotions, but to a lesser degree, when F0 was predetermined. Moreover, females showed fewer significant variations than males. Both genders used more hypofunctional phonation type in mono-pitched utterances than in the expressions with freely varying pitch. The present material warrants further study of the interplay between CQEGG threshold levels and formant frequencies, and listening tests to investigate the perceptual value of the mono-pitched vowels in the communication of emotions.

  12. Improving Enantioselectivity by Using a Mono-Sulphonated Diphosphine as Ligand for Homogeneous Imine Hydrogenation

    NARCIS (Netherlands)

    Lansink, Cornelis; Vries, Johannes G. de

    1992-01-01

    The Rhodium catalysed hydrogenation of acetophenone N-benzylimine using mono-sulphonated (2S,4S)-bis-(diphenylphosphino)pentane as ligand gives the corresponding amine with 94% e.e., whereas use of the di-sulphonated ligand yields product with 2% e.e.

  13. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (Interagency Science Discussion Draft)

    Science.gov (United States)

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from ot...

  14. IRIS Toxicological Review of Ethylene Glycol Mono Butyl Ether (Egbe) (Final Report)

    Science.gov (United States)

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  15. Specific fluorescent detection of fibrillar α-synuclein using mono- and trimethine cyanine dyes

    NARCIS (Netherlands)

    Volkova, K.D.; Kovalska, V.B.; Balanda, A.O.; Losytskyy, M.Yu; Golub, A.G.; Vermeij, R.J.; Subramaniam, V.; Tolmachev, O.I.; Yarmoluk, S.M.

    2008-01-01

    With the aim of searching of novel amyloid-specific fluorescent probes the ability of series of mono- and trimethine cyanines based on benzothiazole, pyridine and quinoline heterocycle end groups to recognize fibrillar formations of α-synuclein (ASN) was studied. For the first time it was revealed t

  16. MONO-PULSE RADAR 3-D IMAGING TECHNIQUES FOR TARGET IN STEPPED TRACKING MODE

    Institute of Scientific and Technical Information of China (English)

    Zhang Tao; Ma Changzheng; Zhang Qun; Zhang Shouhong

    2002-01-01

    A method for mono-pulse radar 3-D imaging in stepped tracking mode is presented and the amplitude linear modulation of error signals in stepped tracking mode is analyzed with its compensation method followed, so the problem of precisely tracking of target is solved. Finally the validity of these methods is proven by the simulation results.

  17. The acute effects of mono(2-ethylhexyl)phthalate (MEHP) on testes of prepubertal Wistar rats

    DEFF Research Database (Denmark)

    Dalgaard, M.; Nellemann, Christine Lydia; Lam, Henrik Rye;

    2001-01-01

    A single oral dose of 400 mg/kg body weight of mono(2-ethylhexyl)phthalate (MEHP), the testis toxic metabolite of di(2-ethylhexyl)phthalate. was given to 28-day-old male Wistar rats and the testis toxic effects were investigated 3, 6. and 12 h after exposure. Detachment and sloughing of germ cell...

  18. Endotoxin testing of proteins for parenteral administration using the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    Pharmaceutical products containing proteins cause problems in testing for endotoxin and pyrogens. Many proteins interfere with the LAL test and the proteins are immunogenic in rabbits. The monocytic cell line Mono Mac 6 is an alternative assay for detection of endotoxin and other pyrogens....

  19. One-step selection of Vaccinia virus-binding DNA aptamers by MonoLEX

    Directory of Open Access Journals (Sweden)

    Stöcklein Walter

    2007-08-01

    Full Text Available Abstract Background As a new class of therapeutic and diagnostic reagents, more than fifteen years ago RNA and DNA aptamers were identified as binding molecules to numerous small compounds, proteins and rarely even to complete pathogen particles. Most aptamers were isolated from complex libraries of synthetic nucleic acids by a process termed SELEX based on several selection and amplification steps. Here we report the application of a new one-step selection method (MonoLEX to acquire high-affinity DNA aptamers binding Vaccinia virus used as a model organism for complex target structures. Results The selection against complete Vaccinia virus particles resulted in a 64-base DNA aptamer specifically binding to orthopoxviruses as validated by dot blot analysis, Surface Plasmon Resonance, Fluorescence Correlation Spectroscopy and real-time PCR, following an aptamer blotting assay. The same oligonucleotide showed the ability to inhibit in vitro infection of Vaccinia virus and other orthopoxviruses in a concentration-dependent manner. Conclusion The MonoLEX method is a straightforward procedure as demonstrated here for the identification of a high-affinity DNA aptamer binding Vaccinia virus. MonoLEX comprises a single affinity chromatography step, followed by subsequent physical segmentation of the affinity resin and a single final PCR amplification step of bound aptamers. Therefore, this procedure improves the selection of high affinity aptamers by reducing the competition between aptamers of different affinities during the PCR step, indicating an advantage for the single-round MonoLEX method.

  20. Classification of All Associative Mono-n-ary Algebras with 2 Elements

    Directory of Open Access Journals (Sweden)

    Stephan Dominique Andres

    2009-01-01

    of these associative mono--ary algebras with 2 elements for even ≥2 and 6 for odd ≥3. These algebras are described explicitly. It is shown that a similar result is impossible for algebras with at least 4 elements. An application concerning the assignment of a control bit to a string is given.

  1. Bioconversion of Mono- and Sesquiterpenoids by Recombinant Human Cytochrome P450 Monooxygenases

    NARCIS (Netherlands)

    Julsing, Mattijs K.; Fichera, Mario A.; Malz, Frank; Ebbelaar, Monique; Bos, Rein; Woerdenbag, Herman J.; Quax, Wim J.; Kayser, Oliver

    2008-01-01

    Cytochrome P450 monooxygenases play an important role in the biosynthesis and metabolism of terpenoids. We explored the potential of recombinant human liver cytochrome P450 monooxygenases CYP1A2, CYP2C9, and CYP3A4, heterologously expressed in Escherichia coli, to convert mono- and sesquiterpenoids

  2. Síntesis de mono y diitaconatos de alquilo y arilo

    Directory of Open Access Journals (Sweden)

    Francisco J. Sánchez

    2011-10-01

    Full Text Available Se presenta una técnica para la síntesis en laboratorio de mono y diitaconatos y la separación de los mismos por extracción selectiva con solventes orgánicos. La pureza de los productos se determina por cromatografía en capa fina y por espectroscopia infrarroja.

  3. Some transition metal complexes derived from mono- and di-ethynyl perfluorobenzenes

    NARCIS (Netherlands)

    Armitt, D.J.; Bruce, M.I.; Gaudio, M.; Zaitseva, N.N.; Skelton, B.W.; White, A.H.; Le Guennic, B.; Halet, J.-F.; Fox, M.A.; Roberts, R.L.; Hartl, F.; Low, P.J.

    2008-01-01

    Transition metal alkynyl complexes containing perfluoroaryl groups have been prepared directly from trimethylsilyl-protected mono- and di-ethynyl perfluoroarenes by simple desilylation/metallation reaction sequences. Reactions between Me3SiC CC6F5 and RuCl(dppe)Cp'[Cp' = Cp, Cp*] in the presence of

  4. (II) and Zn (II) ions in mono-element and the bi-element aqueous ...

    African Journals Online (AJOL)

    Joseph

    and zinc (II) ions (Cu2+ and Zn2+) in mono-element and binary aqueous solutions. The experiments were carried out .... (1998) proposed a model that allows to evaluate the adsorption capacity of ...... 2(8):875- 878. Tien CT, Huang CP (1991).

  5. 76 FR 38026 - Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2011-06-29

    ... butyl ether, also a glycol ether differing in only one ethyl group from DEGBE. These data were used to... monobutyl ether, also a glycol ether differing only in one ethyl group. This data was used to assess the... AGENCY 40 CFR Part 180 Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a...

  6. Prevalence, Risk Factors, and Treatment Outcomes of Isoniazid- and Rifampicin-Mono-Resistant Pulmonary Tuberculosis in Lima, Peru.

    Directory of Open Access Journals (Sweden)

    Leonela Villegas

    Full Text Available Isoniazid and rifampicin are the two most efficacious first-line agents for tuberculosis (TB treatment. We assessed the prevalence of isoniazid and rifampicin mono-resistance, associated risk factors, and the association of mono-resistance on treatment outcomes.A prospective, observational cohort study enrolled adults with a first episode of smear-positive pulmonary TB from 34 health facilities in a northern district of Lima, Peru, from March 2010 through December 2011. Participants were interviewed and a sputum sample was cultured on Löwenstein-Jensen (LJ media. Drug susceptibility testing was performed using the proportion method. Medication regimens were documented for each patient. Our primary outcomes were treatment outcome at the end of treatment. The secondary outcome included recurrent episodes among cured patients within two years after completion of the treatment.Of 1292 patients enrolled, 1039 (80% were culture-positive. From this subpopulation, isoniazid mono-resistance was present in 85 (8% patients and rifampicin mono-resistance was present in 24 (2% patients. In the multivariate logistic regression model, isoniazid mono-resistance was associated with illicit drug use (adjusted odds ratio (aOR = 2.10; 95% confidence interval (CI: 1.1-4.1, and rifampicin mono-resistance was associated with HIV infection (aOR = 9.43; 95%CI: 1.9-47.8. Isoniazid mono-resistant patients had a higher risk of poor treatment outcomes including treatment failure (2/85, 2%, p-value<0.01 and death (4/85, 5%, p<0.02. Rifampicin mono-resistant patients had a higher risk of death (2/24, 8%, p<0.01.A high prevalence of isoniazid and rifampicin mono-resistance was found among TB patients in our low HIV burden setting which were similar to regions with high HIV burden. Patients with isoniazid and rifampicin mono-resistance had an increased risk of poor treatment outcomes.

  7. Failure Diameter of PBX 9502: Simulations with the SURFplus model

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-03

    SURFplus is a reactive burn model for high explosives aimed at modelling shock initiation and propagation of detonation waves. It utilizes the SURF model for the fast hot-spot reaction plus a slow reaction for the energy released by carbon clustering. A feature of the SURF model is that there is a partially decoupling between burn rate parameters and detonation wave properties. Previously, parameters for PBX 9502 that control shock ini- tiation had been calibrated to Pop plot data (distance-of-run to detonation as a function of shock pressure initiating the detonation). Here burn rate parameters for the high pres- sure regime are adjusted to t the failure diameter and the limiting detonation speed just above the failure diameter. Simulated results are shown for an uncon ned rate stick when the 9502 diameter is slightly above and slightly below the failure diameter. Just above the failure diameter, in the rest frame of the detonation wave, the front is sonic at the PBX/air interface. As a consequence, the lead shock in the neighborhood of the interface is supported by the detonation pressure in the interior of the explosive rather than the reaction immediately behind the front. In the interior, the sonic point occurs near the end of the fast hot-spot reaction. Consequently, the slow carbon clustering reaction can not a ect the failure diameter. Below the failure diameter, the radial extent of the detonation front decreases starting from the PBX/air interface. That is, the failure starts at the PBX boundary and propagates inward to the axis of the rate stick.

  8. Paleomagnetic Excursion Recorded in Exposed Lacustrine Sediments on Paoha Island in Mono Lake, CA.

    Science.gov (United States)

    Liddicoat, J. C.; Coe, R. S.

    2016-12-01

    Paleomagnetic secular variation (PSV) in the Wilson Creek Formation that was deposited in Pleistocene Lake Russell in the Mono Basin, CA, has been known for nearly 50 years. The research began in the late 1960s during a search for the Laschamp Excursion (LE) believed then to have occurred between about 20,000 and 9,000 years ago (Bonhommet and Zahringer, 1969). Although that investigation was unsuccessful in locating the LE in the eroded bank of Wilson Creek on the northwest side of Mono Lake, which is the remnant of Lake Russell, anomalous field behavior was documented that is the Mono Lake Excursion (MLE)(Denham and Cox, 1971; Liddicoat and Coe, 1979). We did a PSV investigation of a portion of the Wilson Creek Formation where it is exposed on Paoha Island in the center of Mono Lake. Using volcanic ash layers from the nearby Mono Craters as stratigraphc marker beds and the tephrochronology of Lajoie (1993), we located anomalous field behavior that is similar to the field behavior during the MLE with some exceptions. One is the onset of negative inclination 45 cm beneath a 7-cm rhyolitic ash bed. That position is four times lower in the formation than negative inclination beneath Ash 15 that is midway in the MLE at three localities in the basin - Wilson Creek, Mill Creek, and Warm Springs (Liddicoat, 1992). Declination, inclination, and relative field intensity (RFI) where we sampled on Paoha Island are different enough from the paleomagnetic field behavior during the MLE that the possibility exists that a second excursion is recorded in the Wilson Creek Formation. We will present the paleomagnetic directions and RFI that are recorded on Paoha Island for that field behavior.

  9. Hole diameters in pet bottles used for fruit fly capture

    Directory of Open Access Journals (Sweden)

    Maurico Paulo Batistella Pasini

    2015-05-01

    Full Text Available Two experiments were conducted during the period from 31 January to 6 March 2012 in Santa Maria, Rio Grande do Sul State, Brazil to determine the efficiency of different hole diameters in PET trap bottles on pests in guava and persimmon orchards. In a randomised block design in a factorial scheme, we assessed the average number adults of Anastrepha fraterculus, Ceratitis capitata (Diptera: Tephitidae and Zaprionus indianus (Diptera: Drosophilidae infruits thatemerged in two situations (in the plant and on the soil; we also assessed the number of captured adults in trap bottlesunder two conditions, different hole diameters and different days after placement of the attractive solution. Smaller diameter sizescaptured more A. fraterculus, C. capitata and Z. indianusadults. The 1.0 cm diameter was the most efficient hole size in reducing the adult emergence of Tephritidae to Z. indianus, whereas the smallest diameter hole sizes, 0.6 and 0.8 cm, showed the highest efficiencies in controlling adult emergence in persimmon fruit and guava fruit.

  10. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum

    Directory of Open Access Journals (Sweden)

    Farshid eSepehrband

    2016-05-01

    Full Text Available Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy, or to infer them indirectly (e.g., using diffusion-weighted MRI. The gamma distribution is a common choice for this purpose (particularly for the inferential approach because it resembles the distribution profile of measured axon diameters which has been consistently shown to be non-negative and right-skewed. In this study we compared a wide range of parametric probability distribution functions against empirical data obtained from electron microscopy images. We observed that the gamma distribution fails to accurately describe the main characteristics of the axon diameter distribution, such as location and scale of the mode and the profile of distribution tails. We also found that the generalized extreme value distribution consistently fitted the measured distribution better than other distribution functions. This suggests that there may be distinct subpopulations of axons in the corpus callosum, each with their own distribution profiles. In addition, we observed that several other distributions outperformed the gamma distribution, yet had the same number of unknown parameters; these were the inverse Gaussian, log normal, log logistic and Birnbaum-Saunders distributions.

  11. Effect of rootstock diameter on apple saplings growth

    Directory of Open Access Journals (Sweden)

    VAHID AVDIU

    2014-03-01

    Full Text Available This research paper presents the results of a field trial with managed nursery trees including two apple cultivars Golden Reinders and Gala Galaxy on the rootstocks M9 and MM 106. In April 2011, the saplings (bench grafted in March 2011 were planted in the distance 100 cm x 35 cm in randomized block design in threecombinations of rootstock diameters (5-7 mm, 7-9 mm, 9-11 mm with threereplications (in total 60 saplings for each apple cultivar-rootstock and combinations in Mirovica, Kosovo. The following parameters were examined: growth, rootstock diameter, scion diameter, and stocks growth dynamic. The experimental design was a ANOVAs one-way analysing two different factors cultivars, rootstocks types and treatments (three combinations of rootstocks diameter. Significant differences were found in scion thickness and sapling growth among the three different combinations of rootstock diameter, dimensions and cultivars. Insignificant were differences were found within factors as cultivar, rootstock and their combinations Key words: Amino acids, Moringa oleifera, poultry manure.

  12. Magnetoimpedance of Electroplated Wires with Large Core Diameters

    Institute of Scientific and Technical Information of China (English)

    C. Sirisathitkul; P. Jantaratana

    2009-01-01

    Monolayered Co and trilayered Co/Cu/Co were electroplated on 485 Μm-diameter Cu wires using the bath pH 2.5. These wires can be functioned as magnetic sensors owing to their magnetoimpedance (Ml) effect. By measuring at four different frequencies (100, 250, 500, and 1000 kHz) and Co thicknesses (2.5, 5.0, 10.0, and 25.0Μm), the Ml ratio of electroplated Co on Cu wires tended to increase with increasing Co thickness and frequency of the driving current. The Co/Cu/Co on Cu wires exhibited even higher Ml ratio. The magnetic layer also regulated the magnetic inductions and anisotropy regardless of the size of nonmagnetic core. Nevertheless, the diameter of the Cu core had a significant effect on the Ml ratio. By comparing with the 47.7 μm-diameter Ag cores electroplated by Co and Co/Cu/Co of the same thickness, the Cu cores with a larger diameter gave rise to a larger Ml ratio because their lower electrical resistance enhanced the crossing effect. Substantial Ml ratio was observed even in a low frequency regime because the skin effect occurred at a low frequency in the case of electroplated wires with large core diameters.

  13. Memory, emotion, and pupil diameter: Repetition of natural scenes.

    Science.gov (United States)

    Bradley, Margaret M; Lang, Peter J

    2015-09-01

    Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes. © 2015 Society for Psychophysiological Research.

  14. Humanos salvajes y monos altruistas. Reflexiones sobre Darwin

    Directory of Open Access Journals (Sweden)

    Martinez Contreras Jorge

    2009-12-01

    .0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} -->

    RESUMEN

     

    Darwin propuso en 1871 que preferiría descender de un mono que de los “salvajes”. El mono es un babuino hamadryas que, en un relato de Brehm, salva a un infante de una jauría. Los “salvajes” son los fueguinos a los que visitó en los años 1830. ¿Por qué Darwin fue tan buen observador del comportamiento animal y por qué no dudo discernir en qué consistía la sociedad de cazadores-recolectores de los cuatro grupos de Tierra del Fuego?. Esto es lo que tratamos de dilucidar en este trabajo.

     

  15. Diameter of basalt columns derived from fracture mechanics bifurcation analysis.

    Science.gov (United States)

    Bahr, H-A; Hofmann, M; Weiss, H-J; Bahr, U; Fischer, G; Balke, H

    2009-05-01

    The diameter of columnar joints forming in cooling basalt and drying starch increases with decreasing growth rate. This observation can be reproduced with a linear-elastic three-dimensional fracture mechanics bifurcation analysis, which has been done for a periodic array of hexagonal columnar joints by considering a bifurcation mode compatible with observations on drying starch. In order to be applicable to basalt columns, the analysis has been carried out with simplified stationary temperature fields. The critical diameter differs from the one derived with a two-dimensional model by a mere factor of 1/2. By taking into account the latent heat released at the solidification front, the results agree fairly well with observed column diameters.

  16. On sub-determinants and the diameter of polyhedra

    CERN Document Server

    Bonifas, Nicolas; Eisenbrand, Friedrich; Hähnle, Nicolai; Niemeier, Martin

    2011-01-01

    We derive a new upper bound on the diameter of a polyhedron P = {x \\in R^n : Ax <= b}, where A \\in Z^{m\\timesn}. The bound is polynomial in n and the largest absolute value of a sub-determinant of A, denoted by \\Delta. More precisely, we show that the diameter of P is bounded by O(\\Delta^2 n^4 log n\\Delta). If P is bounded, then we show that the diameter of P is at most O(\\Delta^2 n^3.5 log n\\Delta). For the special case in which A is a totally unimodular matrix, the bounds are O(n^4 log n) and O(n^3.5 log n) respectively. This improves over the previous best bound of O(m^16 n^3 (log mn)^3) due to Dyer and Frieze.

  17. Axon diameter mapping in crossing fibers with diffusion MRI

    DEFF Research Database (Denmark)

    Zhang, Hui; Dyrby, Tim B; Alexander, Daniel C

    2011-01-01

    tissue than measures derived from diffusion tensor imaging. Most existing techniques for axon diameter mapping assume a single axon orientation in the tissue model, which limits their application to only the most coherently oriented brain white matter, such as the corpus callosum, where the single...... orientation assumption is a reasonable one. However, fiber crossings and other complex configurations are widespread in the brain. In such areas, the existing techniques will fail to provide useful axon diameter indices for any of the individual fiber populations. We propose a novel crossing fiber tissue...... of the technique by establishing reasonable axon diameter indices in the crossing region at the interface of the cingulum and the corpus callosum....

  18. The angular diameter and distance of the Cepheid Zeta Geminorum

    CERN Document Server

    Kervella, P; Perrin, G; Schöller, M; Traub, W A; Lacasse, M D

    2001-01-01

    Cepheids are the primary distance indicators for extragalactic astronomy and therefore are of very high astrophysical interest. Unfortunately, they are rare stars, situated very far from Earth.Though they are supergiants, their typical angular diameter is only a few milliarcseconds, making them very challenging targets even for long-baseline interferometers. We report observations that were obtained in the K prime band (2-2.3 microns), on the Cepheid Zeta Geminorum with the FLUOR beam combiner, installed at the IOTA interferometer. The mean uniform disk angular diameter was measured to be 1.64 +0.14 -0.16 mas. Pulsational variations are not detected at a significant statistical level, but future observations with longer baselines should allow a much better estimation of their amplitude. The distance to Zeta Gem is evaluated using Baade-Wesselink diameter determinations, giving a distance of 502 +/- 88 pc.

  19. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    . The expected development of offshore wind farms is towards larger farms, larger turbines and larger water depths. Monopiles have been applied widely and it is of interest to investigate the possibilities to further optimize the design and in particular the modelling of the soil-structure interaction...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles...... in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...

  20. Reduced arterial diameter during static exercise in humans

    DEFF Research Database (Denmark)

    Olesen, H L; Mitchell, J H; Friedman, D B

    1995-01-01

    of another limb. Static exercise increased heart rate and mean arterial pressure, which were largest during one-leg knee extension. After exercise heart rate and mean arterial pressure returned to the resting level. No changes were recorded in arterial carbon dioxide tension, and the rate of perceived......In eight subjects luminal diameter of the resting limb radial and dorsalis pedis arteries was determined by high-resolution ultrasound (20 MHz). This measurement was followed during rest and during 2 min of static handgrip or of one-leg knee extension at 30% of maximal voluntary contraction...... exertion was approximately 15 units after both types of exercise. The dorsalis pedis arterial diameter was 1.50 +/- 0.20 mm (mean and SE) and the radial AD 2.45 +/- 0.12 mm. During both types of contractions the luminal diameters decreased approximately 3.5% within the first 30 s (P

  1. Directional Solidification and Convection in Small Diameter Crucibles

    Science.gov (United States)

    Chen, J.; Sung, P. K.; Tewari, S. N.; Poirier, D. R.; DeGroh, H. C., III

    2003-01-01

    Pb-2.2 wt% Sb alloy was directionally solidified in 1, 2, 3 and 7 mm diameter crucibles. Pb-Sb alloy presents a solutally unstable case. Under plane-front conditions, the resulting macrosegregation along the solidified length indicates that convection persists even in the 1 mm diameter crucible. Al-2 wt% Cu alloy was directionally solidified because this alloy was expected to be stable with respect to convection. Nevertheless, the resulting macrosegregation pattern and the microstructure in solidified examples indicated the presence of convection. Simulations performed for both alloys show that convection persists for crucibles as small as 0.6 mm of diameter. For the solutally stable alloy, Al-2 wt% Cu, the simulations indicate that the convection arises from a lateral temperature gradient.

  2. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...... in sand by use of physical modelling and comparison of the findings with standard p-y curves. The present research is based on use of the centrifuge facilities at Danish Technical University (DTU), the sole geotechnical centrifuge in Scandinavia. It became evident in the initial phase of the research...... that the available centrifuge facilities at DTU was outdated and the focus was changed to establish up-to-date centrifuge facilities for medium to large diameter piles, and to initiate the research on the behaviour of large diameter piles in sand under static and cyclic loading. Key elements in the establishment...

  3. Application of direct tracking method for measuring electrospun nanofiber diameter

    Directory of Open Access Journals (Sweden)

    M. Ziabari

    2009-03-01

    Full Text Available In this paper, direct tracking method as an image analysis based technique for measuring electrospun nanofiber diameter has been presented and compared with distance transform method. Samples with known characteristics generated using a simulation scheme known as µ-randomness were employed to evaluate the accuracy of the method. Electrospun webs of polyvinyl alcohol (PVA were also used to verify the applicability of the method on real samples. Since direct tracking as well as distance transform require binary input images, micrographs of the electrospun webs obtained from Scanning Electron Microscopy (SEM were first converted to black and white using local thresholding. Direct tracking resulted in more accurate estimations of fiber diameter for simulated images as well as electrospun webs suggesting the usefulness of the method for electrospun nanofiber diameter measurement.

  4. NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos

    CERN Document Server

    Nugent, C R; Bauer, J; Cutri, R M; Kramer, E A; Grav, T; Masiero, J; Sonnett, S; Wright, E L

    2016-01-01

    The Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE) mission continues to detect, track, and characterize minor planets. We present diameters and albedos calculated from observations taken during the second year since the spacecraft was reactivated in late 2013. These include 207 near-Earth asteroids and 8,885 other asteroids. $84\\%$ of the near-Earth asteroids did not have previously measured diameters and albedos by the NEOWISE mission. Comparison of sizes and albedos calculated from NEOWISE measurements with those measured by occultations, spacecraft, and radar-derived shapes shows accuracy consistent with previous NEOWISE publications. Diameters and albedos fall within $ \\pm \\sim20\\%$ and $\\pm\\sim40\\%$, 1-sigma, respectively, of those measured by these alternate techniques. NEOWISE continues to preferentially discover near-Earth objects which are large ($>100$ m), and have low albedos.

  5. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diacetyl tartaric acid esters of mono- and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or...

  6. Swift-heavy ion irradiation-induced latent tracks in few- and mono-layer MoS{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hang; Zhang, Shengxia [Chinese Academy of Sciences (CAS), Institute of Modern Physics, Lanzhou (China); University of Chinese Academy of Sciences, Beijing (China); Sun, Youmei; Zhai, Pengfei; Yao, Huijun; Zeng, Jian; Duan, Jinglai; Hou, Mingdong; Liu, Jie [Chinese Academy of Sciences (CAS), Institute of Modern Physics, Lanzhou (China); Khan, Maaz [Chinese Academy of Sciences (CAS), Institute of Modern Physics, Lanzhou (China); PINSTECH, Nanomaterials Research Group, Physics Division, Nilore, Islamabad (Pakistan)

    2016-04-15

    The latent tracks in mono- and few-layer molybdenum disulfide (MoS{sub 2}) induced by {sup 209}Bi ions with energies of 0.45-1.23 GeV were characterized by atomic force microscopy (AFM). The hillock-like latent tracks were observed on the surface of irradiated monolayer MoS{sub 2}. The diameter of the hillock after deconvolution procedure is 15.8± 1.7 nm and the height is 1.0±0.3 nm. Hillock-like tracks are induced by energy transfer from energetic {sup 209}Bi ions to electron system of MoS{sub 2}, resulting in the ionization and excitation and then the displacement of target atoms. Since Raman spectroscopy is sensitive to damages induced by swift-heavy ion irradiation, the in-plane E{sub 2g}{sup 1} mode (∝385 cm{sup -1}) and the out-of-plane A{sub 1g} mode (∝408 cm{sup -1}) of MoS{sub 2} were investigated. With increasing ion fluence, the A{sub 1g} peak shifts to higher frequencies, and the intensity ratio between A{sub 1g} and E{sub 2g}{sup 1} peak increases. Besides, the A{sub 1g} peak narrows. The evolution of the structural and vibrational properties of MoS{sub 2} with fluence is discussed. It can be concluded that the blue shift and narrowing of A{sub 1g} peak in irradiated MoS{sub 2} is due to the adsorption of oxygen molecules at latent tracks. With decreasing thickness of MoS{sub 2}, the irradiation resistance decreases. (orig.)

  7. Optical coating uniformity of 200mm (8") diameter precut wafers

    Science.gov (United States)

    Burt, Travis C.; Fisher, Mark; Brown, Dean; Troiani, David

    2017-02-01

    Automated spectroscopic profiling (mapping) of a 200 mm diameter near infrared high reflector (centered at 1064 nm) are presented. Spatial resolution at 5 mm or less was achieved using a 5 mm × 1.5 mm monochromatic beam. Reflection changes of 1.0% across the wafer diameter were observed under s-polarized and p- polarized conditions. Redundancy was established for each chord by re-measuring the center of the wafer and reproducibility of approximately platform for angles of incidence in the range 5°stream processing.

  8. On the diameter of the Kronecker product graph

    CERN Document Server

    Hu, Fu-Tao

    2012-01-01

    Let $G_1$ and $G_2$ be two undirected nontrivial graphs. The Kronecker product of $G_1$ and $G_2$ denoted by $G_1\\otimes G_2$ with vertex set $V(G_1)\\times V(G_2)$, two vertices $x_1x_2$ and $y_1y_2$ are adjacent if and only if $(x_1,y_1)\\in E(G_1)$ and $(x_2,y_2)\\in E(G_2)$. This paper presents a formula for computing the diameter of $G_1\\otimes G_2$ by means of the diameters and primitive exponents of factor graphs.

  9. NEOWISE REACTIVATION MISSION YEAR ONE: PRELIMINARY ASTEROID DIAMETERS AND ALBEDOS

    Energy Technology Data Exchange (ETDEWEB)

    Nugent, C. R.; Cutri, R. M. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Mainzer, A.; Masiero, J.; Bauer, J.; Kramer, E.; Sonnett, S.; Stevenson, R. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Grav, T. [Planetary Science Institute, Tucson, AZ (United States); Wright, E. L., E-mail: cnugent@ipac.caltech.edu [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)

    2015-12-01

    We present preliminary diameters and albedos for 7956 asteroids detected in the first year of the NEOWISE Reactivation mission. Of those, 201 are near-Earth asteroids and 7755 are Main Belt or Mars-crossing asteroids. 17% of these objects have not been previously characterized using the Near-Earth Object Wide-field Infrared Survey Explorer, or “NEOWISE” thermal measurements. Diameters are determined to an accuracy of ∼20% or better. If good-quality H magnitudes are available, albedos can be determined to within ∼40% or better.

  10. Dust Generation Resulting from Desiccation of Playa Systems: Studies on Mono and Owens Lakes, California

    Science.gov (United States)

    Gill, Thomas Edward

    1995-01-01

    Playas, evaporites, and aeolian sediments frequently are linked components within the Earth system. Anthropogenic water diversions from terminal lakes form playas that release fugitive dust. These actions, documented worldwide, simulate aeolian processes activated during palaeoclimatic pluvial/interpluvial transitions, and have significant environmental impacts. Pluvial lakes Russell and Owens in North America's Great Basin preceded historic Mono and Owens Lakes, now desiccated by water diversions into dust-generating, evaporite -encrusted playas. Geochemical and hydrologic cycles acting on the Owens (Dry) Lake playa form three distinct crust types each year. Although initial dust production results from deflation of surface efflorescences after the playa dries, most aerosols are created by saltation abrasion of salt/silt/clay crusts at crust/ sand sheet contacts. The warm-season, clastic "cemented" crust is slowest to degrade into dust. If the playa surface is stabilized by an unbroken, non-efflorescent crust, dust formation is discouraged. When Mono Lake's surFace elevation does not exceed 1951 meters (6400 feet), similar processes will also generate dust from its saline lower playa. Six factors--related to wind, topography, groundwater, and sediments--control dust formation at both playas. These factors were combined into a statistical model relating suspended dust concentrations to playa/lake morphometry. The model shows the extent and severity of Mono Lake dust storms expands significantly below the surface level 6376 feet (1943.5 meters). X-ray diffraction analysis of Mono Basin soils, playa sediments, and aerosols demonstrates geochemical cycling of materials through land, air and water during Mono Lake's 1982 low stand. Soils and clastic playa sediments contain silicate minerals and tephra. Saline groundwater deposited calcite, halite, thenardite, gaylussite, burkeite and glauberite onto the lower playa. Aerosols contained silicate minerals (especially

  11. Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions

    Science.gov (United States)

    Peacock, Jared R.; Mangan, Margaret T.; McPhee, Darcy K.; Ponce, David A.

    2015-01-01

    A three–dimensional (3D) electrical resistivity model of Mono Basin in eastern California unveils a complex subsurface filled with zones of partial melt, fluid–filled fracture networks, cold plutons, and regional faults. In 2013, 62 broadband magnetotelluric (MT) stations were collected in an array around southeastern Mono Basin from which a 3D electrical resistivity model was created with a resolvable depth of 35 km. Multiple robust electrical resistivity features were found that correlate with existing geophysical observations. The most robust features are two 300 ± 50 km3 near-vertical conductive bodies (3–10 Ω·m) that underlie the southeast and north-eastern margin of Mono Craters below 10 km depth. These features are interpreted as magmatic crystal–melt mush zones of 15 ± 5% interstitial melt surrounded by hydrothermal fluids and are likely sources for Holocene eruptions. Two conductive east–dipping structures appear to connect each magma source region to the surface. A conductive arc–like structure (< 0.9 Ω·m) links the northernmost mush column at 10 km depth to just below vents near Panum Crater, where the high conductivity suggests the presence of hydrothermal fluids. The connection from the southernmost mush column at 10 km depth to below South Coulée is less obvious with higher resistivity (200 Ω·m) suggestive of a cooled connection. A third, less constrained conductive feature (4–10 Ω·m) 15 km deep extending to 35 km is located west of Mono Craters near the eastern front of the Sierra Nevada escarpment, and is coincident with a zone of sporadic, long–period earthquakes that are characteristic of a fluid-filled (magmatic or metamorphic) fracture network. A resistive feature (103–105 Ω·m) located under Aeolian Buttes contains a deep root down to 25 km. The eastern edge of this resistor appears to structurally control the arcuate shape of Mono Craters. These observations have been combined to form a new conceptual model

  12. Mixed effect models for predicting breast height diameter from stump diameter of Oriental beech in Göldağ

    Directory of Open Access Journals (Sweden)

    Ilker Ercanli

    2015-06-01

    Full Text Available Diameter at breast height (DBH is the simplest, most common and most important tree dimension in forest inventory and is closely correlated with wood volume, height and biomass. In this study, a number of linear and nonlinear models predicting diameter at breast height from stump diameter were developed and evaluated for Oriental beech (Fagus orientalisLipsky stands located in the forest region of Ayancık, in the northeast of Turkey. A set of 1,501 pairs of diameter at breast height-stump measurements, originating from 70 sample plots of even-aged Oriental beech stands, were used in this study. About 80 % of the otal data (1,160 trees in 55 sample plots was used to fit a number of linear and nonlinear model parameters; the remaining 341 trees in 15 sample plots were randomly reserved for model validation and calibration response. The power model data set was found to produce the most satisfactory fits with the Adjusted Coefficient of Determination, R2adj (0.990, Root Mean Square Error, RMSE (1.25, Akaike’s Information Criterion, AIC (3820.5, Schwarz’s Bayesian Information Criterion, BIC (3837.2, and Absolute Bias (1.25. The nonlinear mixed-effect modeling approach for power model with R2adj(0.993, AIC (3598, BIC (3610.1, Absolute Bias (0.73 and RMSE (1.04 provided much better fitting and precise predictions for DBH from stump diameter than the conventional nonlinear fixed effect model structures for this model. The calibration response including tree DBH and stump diameter measurements of the four largest trees in a calibrated sample plot in calibration produced the highest Bias, -5.31 %, and RMSE, -6.30 %, the greatest reduction percentage.

  13. Uncertainty budget for optical coordinate measurements of circle diameter

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertain...

  14. Experimental study on strain sensing by small-diameter FBG

    Science.gov (United States)

    Liu, Rong-mei; Li, Qiufeng; Zhu, Lujia; Liang, Dakai

    2016-11-01

    Fiber Bragg grating (FBG) sensors were attractive in various fields for structural health monitoring. Because of their accurate performance and real time response, embedded FBG sensors are promising for strain monitoring in composite materials. As an optical fiber sensor was embedded inside a composite, interface would form around the embedded optical fiber and the host polymer composite. In order to study the influence of the embedded optical fiber to the mechanical character, finite elemental analysis was applied to study the stress distribution inside the composite. Keeping the resin rich area the same size, laminates with optical fibers in different diameters, which were 250 and 125 micrometers, were analyzed. The simulation results represent that stress singularity would occur around the embedded optical fiber. The singularity value for the laminate with optical fiber at 250 micrometer was higher than that with optical fiber at 125 micrometer. Micro- cracks would arise at the stress singularity point. Therefore, the optical fiber in smaller diameter was preferred since the mechanical strength could be higher. Four points bending test was carried out on a steel beam with a small-diameter FBG on the bottom surface. Besides, a strain gauge was stuck on bottom to validate the monitoring results by FBG sensor. The tested results indicated that the strain monitoring results by the small-diameter FBG sensor almost identical with the theoretical ones and what recorded by strain gauge. The maximum testing error for the designed FBG is less than 2% compared with the theoretical one.

  15. Predicted and observed finger diameters in field soils

    NARCIS (Netherlands)

    Ritsema, C.J.; Steenhuis, T.S.; Parlange, J.Y.; Dekker, L.W.

    1996-01-01

    Wetting front instability resulting in fingered flow has been found in both wettable and non-wettable soils. Laboratory research has resulted in a number of expressions for finger diameter. The applicability of one of these equations was tested for three soils where detailed soil moisture contents w

  16. Pupil diameter covaries with BOLD activity in human locus coeruleus.

    Science.gov (United States)

    Murphy, Peter R; O'Connell, Redmond G; O'Sullivan, Michael; Robertson, Ian H; Balsters, Joshua H

    2014-08-01

    The locus coeruleus-noradrenergic (LC-NA) neuromodulatory system has been implicated in a broad array of cognitive processes, yet scope for investigating this system's function in humans is currently limited by an absence of reliable non-invasive measures of LC activity. Although pupil diameter has been employed as a proxy measure of LC activity in numerous studies, empirical evidence for a relationship between the two is lacking. In the present study, we sought to rigorously probe the relationship between pupil diameter and BOLD activity localized to the human LC. Simultaneous pupillometry and fMRI revealed a relationship between continuous pupil diameter and BOLD activity in a dorsal pontine cluster overlapping with the LC, as localized via neuromelanin-sensitive structural imaging and an LC atlas. This relationship was present both at rest and during performance of a two-stimulus oddball task, with and without spatial smoothing of the fMRI data, and survived retrospective image correction for physiological noise. Furthermore, the spatial extent of this pupil/LC relationship guided a volume-of-interest analysis in which we provide the first demonstration in humans of a fundamental characteristic of animal LC activity: phasic modulation by oddball stimulus relevance. Taken together, these findings highlight the potential for utilizing pupil diameter to achieve a more comprehensive understanding of the role of the LC-NA system in human cognition.

  17. Rowlinson’s concept of an effective hard sphere diameter

    Science.gov (United States)

    Henderson, Douglas

    2010-01-01

    Attention is drawn to John Rowlinson’s idea that the repulsive portion of the intermolecular interaction may be replaced by a temperature-dependent hard sphere diameter. It is this approximation that made the development of perturbation theory possible for realistic fluids whose intermolecular interactions have a steep, but finite, repulsion at short separations. PMID:20953320

  18. Rowlinson's concept of an effective hard sphere diameter.

    Science.gov (United States)

    Henderson, Douglas

    2010-01-01

    Attention is drawn to John Rowlinson's idea that the repulsive portion of the intermolecular interaction may be replaced by a temperature-dependent hard sphere diameter. It is this approximation that made the development of perturbation theory possible for realistic fluids whose intermolecular interactions have a steep, but finite, repulsion at short separations.

  19. FACES WITH LARGE DIAMETER ON THE SYMMETRICAL TRAVELING SALESMAN POLYTOPE

    NARCIS (Netherlands)

    SIERKSMA, G; TIJSSEN, GA

    1992-01-01

    This paper deals with the symmetric traveling salesman polytope and contains three main theorems. The first one gives a new characterization of (non)adjacency. Based on this characterization a new upper bound for the diameter of the symmetric traveling salesman polytope (conjectured to be 2 by M. Gr

  20. Definition of Beam Diameter for Electron Beam Welding

    Energy Technology Data Exchange (ETDEWEB)

    Burgardt, Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pierce, Stanley W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dvornak, Matthew John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-11

    It is useful to characterize the dimensions of the electron beam during process development for electron beam welding applications. Analysis of the behavior of electron beam welds is simplest when a single number can be assigned to the beam properties that describes the size of the beam spot; this value we generically call the “beam diameter”. This approach has worked well for most applications and electron beam welding machines with the weld dimensions (width and depth) correlating well with the beam diameter. However, in recent weld development for a refractory alloy, Ta-10W, welded with a low voltage electron beam machine (LVEB), it was found that the weld dimensions (weld penetration and weld width) did not correlate well with the beam diameter and especially with the experimentally determined sharp focus point. These data suggest that the presently used definition of beam diameter may not be optimal for all applications. The possible reasons for this discrepancy and a suggested possible alternative diameter definition is the subject of this paper.

  1. Calibration of Laser Beam Direction for Inner Diameter Measuring Device

    Directory of Open Access Journals (Sweden)

    Tongyu Yang

    2017-02-01

    Full Text Available The laser triangulation method is one of the most advanced methods for large inner diameter measurement. Our research group proposed a kind of inner diameter measuring device that is principally composed of three laser displacement sensors known to be fixed in the same plane measurement position. It is necessary to calibrate the direction of the laser beams that are emitted by laser displacement sensors because they do not meet the theoretical model accurately. For the purpose of calibrating the direction of laser beams, a calibration method and mathematical model were proposed. The inner diameter measuring device is equipped with the spindle of the machine tool. The laser beams rotate and translate in the plane and constitute the rotary rays which are driven to scan the inner surface of the ring gauge. The direction calibration of the laser beams can be completed by the sensors’ distance information and corresponding data processing method. The corresponding error sources are analyzed and the validity of the method is verified. After the calibration, the measurement error of the inner diameter measuring device reduced from ± 25 μ m to ± 15 μ m and the relative error was not more than 0.011%.

  2. Diameter-dependent conductance of InAs nanowires

    NARCIS (Netherlands)

    Scheffler, M.; Nadj-Perge, S.; Kouwenhoven, L.P.; Borgström, M.T.; Bakkers, E.P.A.M.

    2009-01-01

    Electrical conductance through InAs nanowires is relevant for electronic applications as well as for fundamental quantum experiments. Here, we employ nominally undoped, slightly tapered InAs nanowires to study the diameter dependence of their conductance. By contacting multiple sections of each wire

  3. Asteroid magnitudes, UBV colors, and IRAS albedos and diameters

    Science.gov (United States)

    Tedesco, Edward F.

    1989-01-01

    This paper lists absolute magnitudes and slope parameters for known asteroids numbered through 3318. The values presented are those used in reducing asteroid IR flux data obtained with the IRAS. U-B colors are given for 938 asteroids, and B-V colors are given for 945 asteroids. The IRAS albedos and diameters are tabulated for 1790 asteroids.

  4. A small-diameter NMR logging tool for groundwater investigations.

    Science.gov (United States)

    Walsh, David; Turner, Peter; Grunewald, Elliot; Zhang, Hong; Butler, James J; Reboulet, Ed; Knobbe, Steve; Christy, Tom; Lane, John W; Johnson, Carole D; Munday, Tim; Fitzpatrick, Andrew

    2013-01-01

    A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including surface electronics and various downhole probes, has been successfully tested in small-diameter monitoring wells in a range of hydrogeological settings. A variant of the probe that can be deployed by a direct-push machine has also been developed and tested in the field. The new NMR logging tool provides reliable, direct, and high-resolution information that is of importance for groundwater studies. Specifically, the technology provides direct measurement of total water content (total porosity in the saturated zone or moisture content in the unsaturated zone), and estimates of relative pore-size distribution (bound vs. mobile water content) and hydraulic conductivity. The NMR measurements show good agreement with ancillary data from lithologic logs, geophysical logs, and hydrogeologic measurements, and provide valuable information for groundwater investigations.

  5. Estimating Tree Height-Diameter Models with the Bayesian Method

    Directory of Open Access Journals (Sweden)

    Xiongqing Zhang

    2014-01-01

    Full Text Available Six candidate height-diameter models were used to analyze the height-diameter relationships. The common methods for estimating the height-diameter models have taken the classical (frequentist approach based on the frequency interpretation of probability, for example, the nonlinear least squares method (NLS and the maximum likelihood method (ML. The Bayesian method has an exclusive advantage compared with classical method that the parameters to be estimated are regarded as random variables. In this study, the classical and Bayesian methods were used to estimate six height-diameter models, respectively. Both the classical method and Bayesian method showed that the Weibull model was the “best” model using data1. In addition, based on the Weibull model, data2 was used for comparing Bayesian method with informative priors with uninformative priors and classical method. The results showed that the improvement in prediction accuracy with Bayesian method led to narrower confidence bands of predicted value in comparison to that for the classical method, and the credible bands of parameters with informative priors were also narrower than uninformative priors and classical method. The estimated posterior distributions for parameters can be set as new priors in estimating the parameters using data2.

  6. Real-time precision measuring device of tree diameter growth

    Science.gov (United States)

    Guo, Mingming; Chen, Aijun; Li, Dongsheng; Liu, Nan; Yao, Jingyuan

    2016-01-01

    DBH(diameter at breast height) is an important factor to reflect of the quality of plant growth, also an important parameter indispensable in forest resources inventory and forest carbon sink, the accurate measurement of DBH or not is directly related to the research of forest resources inventory and forest carbon sink. In this paper, the principle and the mathematical model of DBH measurement device were introduced, the fixture measuring device and the hardware circuit for this tree diameter were designed, the measurement software programs were compiled, and the precision measuring device of tree diameter growth was developed. Some experiments with Australia fir were conducted. Based on experiment data, the correlations among the DBH variation of Australian fir, the environment temperature, air humility and PAR(photosynthetically active radiation) were obtained. The effects of environmental parameters (environment temperature, air humility and PAR) on tree diameter were analyzed. Experimental results show that there is a positive correlation between DBH variation of Australian fir and environment temperature, a negative correlation between DBH variation of Australian fir and air humility , so is PAR.

  7. The Angular Diameter and Fundamental Parameters of Sirius A

    CERN Document Server

    Davis, J; North, J R; Robertson, J G; Tango, W J; Tuthill, P G

    2010-01-01

    The Sydney University Stellar Interferometer (SUSI) has been used to make a new determination of the angular diameter of Sirius A. The observations were made at an effective wavelength of 694.1 nm and the new value for the limb-darkened angular diameter is 6.048 +/- 0.040mas (+/-0.66%). This new result is compared with previous measurements and is found to be in excellent agreement with a conventionally calibrated measurement made with the European Southern Observatory's Very Large Telescope Interferometer (VLTI) at 2.176 microns (but not with a second globally calibrated VLTI measurement). A weighted mean of the SUSI and first VLTI results gives the limb-darkened angular diameter of Sirius A as 6.041 +/- 0.017mas (+/-0.28%). Combination with the Hipparcos parallax gives the radius equal to 1.713 +/- 0.009R_sun. The bolometric flux has been determined from published photometry and spectrophotometry and, combined with the angular diameter, yields the emergent flux at the stellar surface equal to (5.32+/- 0.14)...

  8. Observations on placentome diameters in gestating West African ...

    African Journals Online (AJOL)

    ADEYEYE

    2015-09-09

    Sep 9, 2015 ... Department of Veterinary Surgery and Reproduction, University of Ibadan, Ibadan, Nigeria ... This study investigated the effect of experimental Trypanosoma brucei infection on the placentome diameter (PD) ... symptoms/clinical signs in female mammalian ..... Global Library Women's Medicine, London,.

  9. Small-diameter trees used for chemithermomechanical pulps.

    Science.gov (United States)

    Gary C. Myers; R. James. Barbour; Said M. Abubakr

    1999-01-01

    During the course of restoring and maintaining forest ecosystem health and function in the western interior of the United States, many small-diameter stems are removed from densely stocked stands. In general, these materials are considered nonusable or underutilized. Information on the properties of these resources is needed to help managers understand when timber...

  10. Processing of fine-diameter continuous mullite fibers

    Energy Technology Data Exchange (ETDEWEB)

    Al-Assafi, S.; Cruse, T.; Simmons, J.H. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1994-12-31

    Fine-diameter, continuous mullite fibers were fabricated by sol-gel processing using two different chelating agents on weight loss behavior, mullite formation, and sintered fiber microstructure were examined. The molar ratio, R, of chelating agent to alumina precursor in the sol was varied in order to optimize continuous spinning conditions. The importance of aging conditions on the sintered fiber density was demonstrated.

  11. Bipartite Diametrical Graphs of Diameter 4 and Extreme Orders

    Directory of Open Access Journals (Sweden)

    Salah Al-Addasi

    2008-01-01

    in which this upper bound is attained, this graph can be viewed as a generalization of the Rhombic Dodecahedron. Then we show that for any ≥2, the graph (2,2 is the unique (up to isomorphism bipartite diametrical graph of diameter 4 and partite sets of cardinalities 2 and 2, and hence in particular, for =3, the graph (6,8 which is just the Rhombic Dodecahedron is the unique (up to isomorphism bipartite diametrical graph of such a diameter and cardinalities of partite sets. Thus we complete a characterization of -graphs of diameter 4 and cardinality of the smaller partite set not exceeding 6. We prove that the neighborhoods of vertices of the larger partite set of (2,2 form a matroid whose basis graph is the hypercube . We prove that any -graph of diameter 4 is bipartite self complementary, thus in particular (2,2. Finally, we study some additional properties of (2,2 concerning the order of its automorphism group, girth, domination number, and when being Eulerian.

  12. 1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Energy Technology Data Exchange (ETDEWEB)

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  13. 1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Energy Technology Data Exchange (ETDEWEB)

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  14. Multi-diameter pigging: factors affecting the design and selection of pigging tools for multi-diameter pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Karl [Pipeline Engineering and Supply Co. Ltd., Richmond, NY (United States)

    2009-07-01

    This paper will consider the process involved in pigging tool selection for pipelines with two or more significant internal diameters which require pigging tools capable of negotiating the different internal diameters whilst also carrying out the necessary pipeline cleaning operation. The paper will include an analysis of pipeline features that affect pigging tool selection and then go on to look at other variables that determine the pigging tool design; this will include a step by step guide outlining how the tool is designed, the development of prototype pigs and the importance of testing and validation prior to final deployment in operational pigging programmes. (author)

  15. Vertebral Artery Diameter and Flow: Nature or Nurture.

    Science.gov (United States)

    Tarnoki, Adam Domonkos; Fejer, Bence; Tarnoki, David Laszlo; Littvay, Levente; Lucatelli, Pierleone; Cirelli, Carlo; Fanelli, Fabrizio; Sacconi, Beatrice; Fagnani, Corrado; Medda, Emanuela; Farina, Filippo; Meneghetti, Giorgio; Horvath, Tamas; Pucci, Giacomo; Schillaci, Giuseppe; Stazi, Maria Antonietta; Baracchini, Claudio

    2017-09-01

    In contrast with the carotid arteries, the vertebral arteries (VAs) show considerable variation in length, caliber, and vessel course. This study investigated whether the variation in diameter and flow characteristics of the VAs might be inherited. A total of 172 Italian twins from Padua, Perugia, and Terni (54 monozygotic, 32 dizygotic) recruited from the Italian Twin Registry underwent B-mode and pulsed-wave Doppler ultrasound assessment of their VAs. VA diameters, peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at the level of a horizontal V2 segment. Univariate quantitative genetic modeling was performed. Fourteen percent of the sample had VA hypoplasia. Within pair correlation in monozygotic twins was higher than in dizygotics (.552 vs. .229) for VA diameter. Age- and sex-adjusted genetic effect, under the most parsimonious model, accounted for 54.7% (95% CI: 42.2-69.1%) of the variance of VA diameter, and unshared environmental effect for 45.3% (95% CI: 30.9-57.8%). No heritability was found for the PSV of VA, but shared (34.1%; 95% CI: 16.7-53.7%) and unshared (65.9%; 95% CI: 45.9-83.1%) environmental factors determined the variance. EDV of VA is moderately genetically influenced (42.4%; 95% CI: 16.1-64.9%) and also determined by the unshared environment (57.6%; 95% CI: 34.7-83.7%). The diameter of the VAs is moderately genetically determined. Different factors influence the PSV and EDV of VAs, which may highlight the complex hemodynamic background of VA flow and help to understand the vertebral flow anomalies found by ultrasound. Copyright © 2017 by the American Society of Neuroimaging.

  16. Stand diameter distribution modelling and prediction based on Richards function.

    Directory of Open Access Journals (Sweden)

    Ai-guo Duan

    Full Text Available The objective of this study was to introduce application of the Richards equation on modelling and prediction of stand diameter distribution. The long-term repeated measurement data sets, consisted of 309 diameter frequency distributions from Chinese fir (Cunninghamia lanceolata plantations in the southern China, were used. Also, 150 stands were used as fitting data, the other 159 stands were used for testing. Nonlinear regression method (NRM or maximum likelihood estimates method (MLEM were applied to estimate the parameters of models, and the parameter prediction method (PPM and parameter recovery method (PRM were used to predict the diameter distributions of unknown stands. Four main conclusions were obtained: (1 R distribution presented a more accurate simulation than three-parametric Weibull function; (2 the parameters p, q and r of R distribution proved to be its scale, location and shape parameters, and have a deep relationship with stand characteristics, which means the parameters of R distribution have good theoretical interpretation; (3 the ordinate of inflection point of R distribution has significant relativity with its skewness and kurtosis, and the fitted main distribution range for the cumulative diameter distribution of Chinese fir plantations was 0.4∼0.6; (4 the goodness-of-fit test showed diameter distributions of unknown stands can be well estimated by applying R distribution based on PRM or the combination of PPM and PRM under the condition that only quadratic mean DBH or plus stand age are known, and the non-rejection rates were near 80%, which are higher than the 72.33% non-rejection rate of three-parametric Weibull function based on the combination of PPM and PRM.

  17. Stand diameter distribution modelling and prediction based on Richards function.

    Science.gov (United States)

    Duan, Ai-guo; Zhang, Jian-guo; Zhang, Xiong-qing; He, Cai-yun

    2013-01-01

    The objective of this study was to introduce application of the Richards equation on modelling and prediction of stand diameter distribution. The long-term repeated measurement data sets, consisted of 309 diameter frequency distributions from Chinese fir (Cunninghamia lanceolata) plantations in the southern China, were used. Also, 150 stands were used as fitting data, the other 159 stands were used for testing. Nonlinear regression method (NRM) or maximum likelihood estimates method (MLEM) were applied to estimate the parameters of models, and the parameter prediction method (PPM) and parameter recovery method (PRM) were used to predict the diameter distributions of unknown stands. Four main conclusions were obtained: (1) R distribution presented a more accurate simulation than three-parametric Weibull function; (2) the parameters p, q and r of R distribution proved to be its scale, location and shape parameters, and have a deep relationship with stand characteristics, which means the parameters of R distribution have good theoretical interpretation; (3) the ordinate of inflection point of R distribution has significant relativity with its skewness and kurtosis, and the fitted main distribution range for the cumulative diameter distribution of Chinese fir plantations was 0.4∼0.6; (4) the goodness-of-fit test showed diameter distributions of unknown stands can be well estimated by applying R distribution based on PRM or the combination of PPM and PRM under the condition that only quadratic mean DBH or plus stand age are known, and the non-rejection rates were near 80%, which are higher than the 72.33% non-rejection rate of three-parametric Weibull function based on the combination of PPM and PRM.

  18. Arteriolar Diameters in Glaucomatous Eyes with Single-Hemifield Damage.

    Science.gov (United States)

    Russo, Andrea; Costagliola, Ciro; Rizzoni, Damiano; Ghilardi, Nausica; Turano, Raffaele; Semeraro, Francesco

    2016-05-01

    To examine the association between retinal arteriolar caliber and lumen, retinal sensitivity (RS), and retinal nerve fiber layer (RNFL) thickness in glaucomatous eyes with single-hemifield loss. We conducted a prospective, nonrandomized, case-control study of 20 eyes of 20 patients with glaucoma with visual field damage confined to a single hemifield. The control group was composed of 20 eyes of 20 normal subjects. For all the eyes, we performed optical coherence tomography to assess the RNFL and standard automated perimetry to evaluate RS. External and internal arteriolar diameters were assessed in vivo using scanning laser Doppler flowmetry. The RNFL was significantly thinner in glaucomatous eyes than in normal eyes (p < 0.001). In glaucomatous eyes, a positive correlation between sectorial RNFL thickness and the corresponding external and internal arteriolar diameters was found (r = 0.43, p = 0.05; r = 0.63, p = 0.003, respectively). The internal arteriolar diameter significantly correlated with RS in the corresponding abnormal hemifield (r = 0.44, p = 0.04). Compared with the normal hemifield, the internal arteriolar diameter, RNFL thickness, and RS were significantly reduced, whereas the external arteriolar diameter was unchanged in the abnormal hemifield. In glaucomatous eyes with single-hemifield damage, attenuation of retinal vessels was associated with a thinner RNFL and reduced RS. Moreover, a narrower lumen with increased wall-to-lumen ratio was found in the abnormal hemifield, supporting the hypothesis that vessel narrowing is likely secondary to a lower demand for blood flow in the glaucomatous areas of the retina.

  19. Measurement error in CT assessment of appendix diameter

    Energy Technology Data Exchange (ETDEWEB)

    Trout, Andrew T.; Towbin, Alexander J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, MLC 5031, Cincinnati, OH (United States); Zhang, Bin [Cincinnati Children' s Hospital Medical Center, Department of Biostatistics and Epidemiology, Cincinnati, OH (United States)

    2016-12-15

    Appendiceal diameter continues to be cited as an important criterion for diagnosis of appendicitis by computed tomography (CT). To assess sources of error and variability in appendiceal diameter measurements by CT. In this institutional review board-approved review of imaging and medical records, we reviewed CTs performed in children <18 years of age between Jan. 1 and Dec. 31, 2010. Appendiceal diameter was measured in the axial and coronal planes by two reviewers (R1, R2). One year later, 10% of cases were remeasured. For patients who had multiple CTs, serial measurements were made to assess within patient variability. Measurement differences between planes, within and between reviewers, within patients and between CT and pathological measurements were assessed using correlation coefficients and paired t-tests. Six hundred thirty-one CTs performed in 519 patients (mean age: 10.9 ± 4.9 years, 50.8% female) were reviewed. Axial and coronal measurements were strongly correlated (r = 0.92-0.94, P < 0.0001) with coronal plane measurements significantly larger (P < 0.0001). Measurements were strongly correlated between reviewers (r = 0.89-0.9, P < 0.0001) but differed significantly in both planes (axial: +0.2 mm, P=0.003; coronal: +0.1 mm, P=0.007). Repeat measurements were significantly different for one reviewer only in the axial plane (0.3 mm difference, P<0.05). Within patients imaged multiple times, measured appendix diameters differed significantly in the axial plane for both reviewers (R1: 0.5 mm, P = 0.031; R2: 0.7 mm, P = 0.022). Multiple potential sources of measurement error raise concern about the use of rigid diameter cutoffs for the diagnosis of acute appendicitis by CT. (orig.)

  20. Design and synthesis of potent inhibitors of the mono(ADP-ribosyl)transferase, PARP14.

    Science.gov (United States)

    Upton, Kristen; Meyers, Matthew; Thorsell, Ann-Gerd; Karlberg, Tobias; Holechek, Jacob; Lease, Robert; Schey, Garrett; Wolf, Emily; Lucente, Adrianna; Schüler, Herwig; Ferraris, Dana

    2017-07-01

    A series of (Z)-4-(3-carbamoylphenylamino)-4-oxobut-2-enyl amides were synthesized and tested for their ability to inhibit the mono-(ADP-ribosyl)transferase, PARP14 (a.k.a. BAL-2; ARTD-8). Two synthetic routes were established for this series and several compounds were identified as sub-micromolar inhibitors of PARP14, the most potent of which was compound 4t, IC50=160nM. Furthermore, profiling other members of this series identified compounds with >20-fold selectivity over PARP5a/TNKS1, and modest selectivity over PARP10, a closely related mono-(ADP-ribosyl)transferase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Literature review on cyclic lateral loading effects of mono-bucket foundations

    DEFF Research Database (Denmark)

    Kapitanov, Lachezar Rosenov; Duroska, Peter; Garcia, Cesar Antonio Garcia

    2016-01-01

    The renewable offshore energy sector is currently growing rapidly and there is a vast interest in optimization of the design procedures for the offshores wind turbines. Mono-Bucket can be a breakthrough in the sphere of offshore wind turbines foundations due to its lightness and fast installation...... and consequently cost-effectiveness compared to other common solutions. The long-term cyclic loading can cause degradation of soil-bucket system stiffness, which yields into accumulated and permanent deformations. Despite of the advantages, there is no standard procedure to design the foundation especially...... for assessing the accumulated deformations under environmental longterm loading. However, numerical and semi-empirical methods already used for offshore foundations can be adopted to take into account the effect of cyclic loading on Mono-Buckets. Among them, load-displacement techniques as cyclic p-y curves...

  2. Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qian; WU Dong-bei; BAO Bo-rong

    2009-01-01

    The synergistic extraction of Pr3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr3+ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration on extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinolinc was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr3+.

  3. Mono-layer BC2 a high capacity anode material for Li-ion batteries

    Science.gov (United States)

    Hardikar, Rahul; Samanta, Atanu; Han, Sang Soo; Lee, Kwang-Ryeol; Singh, Abhishek

    2015-04-01

    Mono-layer of graphene with high surface area compared to the bulk graphite phase, shows less Li uptake. The Li activity or kinetics can be modified via defects and/or substitutional doping. Boron and Nitrogen are the best known dopants for carbonaceous anode materials. In particular, boron doped graphene shows higher capacity and better Li adsorption compared to Nitrogen doped graphene. Here, using first principles density functional theory calculations, we study the spectrum of boron carbide (BCx) mono-layer phases in order to estimate the maximum gravimetric capacity that can be achieved by substitutional doping in graphene. Our results show that uniformly boron doped BC2 phase shows a high capacity of? 1400 mAh/g, much higher than previously reported capacity of BC3. Supported by Korea Institute of Science and Technology.

  4. Nonlinear Optical Properties of Novel Mono-O-Hydroxy Bidentate Schiff Base: Quantum Chemical Calculations

    Directory of Open Access Journals (Sweden)

    N. S. Labidi

    2013-01-01

    Full Text Available The semiempirical AM1 SCF method is used to study the first static hyperpolarizabilities β of some novel mono-O-Hydroxy bidentate Schiff base in which electron donating (D and electron accepting (A groups were introduced on either side of the Schiff base ring system. Geometries of all molecules were optimized at the semiempirical AM1. The first static hyperpolarizabilities of these molecules were calculated using Hyperchem package. To understand this phenomenon in the context of molecular orbital picture, we examined the molecular HOMO and molecular LUMO generated via Hyperchem. The study reveals that the mono-O-Hydroxy bidentate Schiff bases have large β values and hence in general may have potential applications in the development of nonlinear optical materials.

  5. Resurrecting an unsalvageable lower incisor with a mono-block approach

    Science.gov (United States)

    Jain, Rachit; Thomas, Manuel S.; Yadav, Amit

    2015-01-01

    Contemporary techniques, as well as the availability of bioactive and adhesive materials in endodontics, have helped revivifying teeth that were deemed hopeless. These newer materials and techniques would enable the clinician: (a) to predictably stop microbial activity (b) to achieve a total corono-apical fluid tight seal and (c) to strengthen mutilated teeth by obtaining intra-radicular reinforcement through mono-block effect. This case report demonstrates the successful treatment of a mutilated anterior tooth with the use of bioactive and adhesive materials to obtain a total seal and mono-block effect. This article also shows the use of a simple method in the placement of root filling cement into the root canal. PMID:26430310

  6. Couple Control Model Implementation on Antagonistic Mono- and Bi-Articular Actuators

    CERN Document Server

    Prattico, Flavio; Yamamoto, Shin-ichiroh

    2014-01-01

    Recently, robot assisted therapy devices are increasingly used for spinal cord injury (SCI) rehabilitation in assisting handicapped patients to regain their impaired movements. Assistive robotic systems may not be able to cure or fully compensate impairments, but it should be able to assist certain impaired functions and ease movements. In this study, a couple control model for lower-limb orthosis of a body weight support gait training system is proposed. The developed leg orthosis implements the use of pneumatic artificial muscle as an actuation system. The pneumatic muscle was arranged antagonistically to form two pair of mono-articular muscles (i.e., hip and knee joints), and a pair of bi-articular actuators (i.e., rectus femoris and hamstring). The results of the proposed couple control model showed that, it was able to simultaneously control the antagonistic mono- and bi-articular actuators and sufficiently performed walking motion of the leg orthosis.

  7. Rotavirus infection in children: mono-and combines forms, especially clinics and course

    Directory of Open Access Journals (Sweden)

    N. B. Denisyuk

    2012-01-01

    Full Text Available Analyzed 74 case histories of children under one year with rotavirus infection. The most commonly detected rotavirus gastroenteritis in the form of mono-and combined forms. Mono-infection in 78.3% of cases occurred in the moderate form with a leading syndrome in the form of gastroenteritis, severe dehydration proceeded with symptoms of varying severity. Mixed variants in 98.7% of cases are in the unfavorable premorbid background, in 42.8% of children were registered in the severe forms, and children younger than 6 months were erased within. The diagnosis of intestinal infection was confirmed by PCR, bacteriological and immunological methods.

  8. Detection and Quantification of Crack in Composite Mono Leaf Spring by Vibration Parameters

    Science.gov (United States)

    Jamadar, Nagendra Iranna; Kivade, Sangshetty Bheemanna; Pedada, Sudhakara Rao

    2016-06-01

    Automobile industries focus for the components alternative to conventional materials with composites. There is high demand for enhanced performance and light weight. The emphasis is given for composite mono leaf spring as potential item as it is made up of glass fibre reinforced plastics despite they are sensitive to damages such as crack, delamination, de-bonding etc., occurred during either manufacturing or in service condition. These damages grow in progression and results in catastrophic failure. This work aims to deal with structural health monitoring to study and analyse the damage levels in composite mono leaf spring such as detection, location and quantification of damage. An experimental investigation has been carried out to evaluate presence and severity of damage by vibration parameters and validated with simulation.

  9. Resurrecting an unsalvageable lower incisor with a mono-block approach

    Directory of Open Access Journals (Sweden)

    Rachit Jain

    2015-01-01

    Full Text Available Contemporary techniques, as well as the availability of bioactive and adhesive materials in endodontics, have helped revivifying teeth that were deemed hopeless. These newer materials and techniques would enable the clinician: (a to predictably stop microbial activity (b to achieve a total corono-apical fluid tight seal and (c to strengthen mutilated teeth by obtaining intra-radicular reinforcement through mono-block effect. This case report demonstrates the successful treatment of a mutilated anterior tooth with the use of bioactive and adhesive materials to obtain a total seal and mono-block effect. This article also shows the use of a simple method in the placement of root filling cement into the root canal.

  10. Gas chromatographic analysis of synthetic glycidol esters, mono-, di- and triglycerides.

    Science.gov (United States)

    Engbersen, J A; van Stijn, F

    1976-03-01

    The gas chromatographic analysis of glycidol esters and mono-, di-,and triglycerides of palmitic-, stearic-, and oleic acid mixtures is described. The composition of the products was determined by gas chromatography on OV-17 after trimethylsilylation. Base-line separations between 1- and 2-monoglycerides and between 1,2- and 1,3-diglycerides were obtained. Isomerisation of the trimethylsilyl ethers of monoglycerides was not observed, contrary to published work.

  11. Dark Matter searches with Mono-X signatures at the ATLAS experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00377126; The ATLAS collaboration

    2016-01-01

    At the LHC dark matter particles can be produced in association with Standard Model particles coming from initial state radiation. Searches for such processes using events with jets, photons or massive gauge bosons recoiling against large missing transverse momentum in ATLAS at 13 TeV are presented. These ``mono-X'' signatures provide powerful probes to dark matter production at the LHC, allowing for the interpretation of results in terms of simplified models with pair production of WIMPs.

  12. Advantage in solar cell efficiency of high-quality seed cast mono Si ingot

    Science.gov (United States)

    Miyamura, Yoshiji; Harada, Hirofumi; Jiptner, Karolin; Nakano, Satoshi; Gao, Bing; Kakimoto, Koichi; Nakamura, Kyotaro; Ohshita, Yoshio; Ogura, Atsushi; Sugawara, Shin; Sekiguchi, Takashi

    2015-06-01

    We have grown 50 cm2 mono Si ingots by the seed cast technique. The carbon and oxygen concentrations of the ingots have been significantly reduced by improving the gas flow condition and coating. The dislocation density was also reduced by eliminating the extra dislocation generation sources. Owing to these developments, the lifetime of wafers has reached 465 µs. Finally, the efficiency of 18.7% has been achieved, which is comparable to 18.9% of the reference Czochralski (CZ) Si wafer.

  13. SIMAC - A phosphoproteomic strategy for the rapid separation of mono-phosphorylated from multiply phosphorylated peptides

    DEFF Research Database (Denmark)

    Thingholm, Tine E; Jensen, Ole N; Robinson, Phillip J

    2008-01-01

    spectrometric analysis, such as immobilized metal affinity chromatography or titanium dioxide the coverage of the phosphoproteome of a given sample is limited. Here we report a simple and rapid strategy - SIMAC - for sequential separation of mono-phosphorylated peptides and multiply phosphorylated peptides from...... and an optimized titanium dioxide chromatographic method. More than double the total number of identified phosphorylation sites was obtained with SIMAC, primarily from a three-fold increase in recovery of multiply phosphorylated peptides....

  14. First survey of fungi in hypersaline soil and water of Mono Lake area (California).

    Science.gov (United States)

    Steiman, Régine; Ford, Larry; Ducros, Véronique; Lafond, Jean-Luc; Guiraud, Pascale

    2004-01-01

    Mono Lake is a closed lake located in central California, east of the Sierra Nevada mountains. It contains dissolved carbonates, sulfates and chlorides at high concentrations. Due to its high salinity, Mono Lake was sometimes compared to the Dead Sea. However, it appears that Mono Lake water and vicinity abound with life. In this work, the fungal flora living in this extreme ecosystem was studied for the first time. Soil, tufa, water and sediment samples were also analyzed for their mineral and salt composition. Results showed that water was particularly rich in sodium, potassium, phosphorus and boron. Soil and sediments contained very high levels of calcium and magnesium, but also barium, boron and strontium. Sodium, phosphorus and iron levels varied in a large extent from one to another sample. Neutral to very alkaline pH were recorded. Water samples were found sterile in the conditions chosen for fungi isolation, while sediment, soil and tufa samples led to the isolation of a total of 67 fungal species (from 23 samples), belonging to various taxonomic groups. From our results no clear effects of the chemical parameters of the samples were observed on fungal life apart from the pH. The methods chosen did not allow the isolation of extremely halotolerant species. We isolated in this work a series of ubiquitous species, suggesting that a selection of resistant and/or adaptable strains of some common species could have occurred. Depending on the medium and the temperature of isolation, it can be hypothesized that some species were present as dormant structures, while some others, isolated at pH 8 on a medium enriched in Na and Ca, could be in a growing form adapted to alkaline and saline conditions. This work contributes to a better knowledge of the mycobiota present in the Mono Lake's ecosystem.

  15. Nonlinear Optical Properties of Novel Mono-O-Hydroxy Bidentate Schiff Base: Quantum Chemical Calculations

    OpenAIRE

    N. S. Labidi

    2013-01-01

    The semiempirical AM1 SCF method is used to study the first static hyperpolarizabilities β of some novel mono-O-Hydroxy bidentate Schiff base in which electron donating (D) and electron accepting (A) groups were introduced on either side of the Schiff base ring system. Geometries of all molecules were optimized at the semiempirical AM1. The first static hyperpolarizabilities of these molecules were calculated using Hyperchem package. To understand this phenomenon in the context of molecular o...

  16. New concept research on mono-hull compounded ship form with high seakeeping performance

    Institute of Scientific and Technical Information of China (English)

    LIU Ya-dong; LI Ji-de; WANG Qing

    2003-01-01

    The seakeeping performance of a certain ship equipped with semi-submerged bow (SSB) and bow-fins is discussed. The numerical calculations are carried out on a 600t deep-V compound archetypal ship. The results show that the compounded ship form has excellent seakeeping performance and thus it establishes the theoretical foundations for the development of mono-hull compounded ship form with high seakeeping performance.

  17. Strength and nature of hydrogen bonding interactions in mono- and di-hydrated formamide complexes.

    Science.gov (United States)

    Angelina, Emilio L; Peruchena, Nélida M

    2011-05-12

    In this work, mono- and di-hydrated complexes of the formamide were studied. The calculations were performed at the MP2/6-311++G(d,p) level of approximation. The atoms in molecules theory (AIM), based on the topological properties of the electronic density distribution, was used to characterize the different types of bonds. The analysis of the hydrogen bonds (H-bonds) in the most stable mono- and di-hydrated formamide complexes shows a mutual reinforcement of the interactions, and some of these complexes can be considered as "bifunctional hydrogen bonding hydration complexes". In addition, we analyzed how the strength and the nature of the interactions, in mono-hydrated complexes, are modified by the presence of a second water molecule in di-hydrated formamide complexes. Structural changes, cooperativity, and electron density redistributions demonstrate that the H-bonds are stronger in the di-hydrated complexes than in the corresponding mono-hydrated complexes, wherein the σ- and π-electron delocalization were found. To explain the nature of such interactions, we carried out the atoms in molecules theory in conjunction with reduced variational space self-consistent field (RVS) decomposition analysis. On the basis of the local Virial theorem, the characteristics of the local electron energy density components at the bond critical points (BCPs) (the 1/4∇ (2)ρ(b) component of electron energy density and the kinetic energy density) were analyzed. These parameters were used in conjunction with the electron density and the Laplacian of the electron density to analyze the characteristics of the interactions. The analysis of the interaction energy components for the systems considered indicates that the strengthening of the hydrogen bonds is manifested by an increased contribution of the electrostatic energy component represented by the kinetic energy density at the BCP.

  18. Experimental damping assessment of a full scale offshore mono bucket foundation

    DEFF Research Database (Denmark)

    Gres, Szymon; Fejerskov, Morten; Ibsen, Lars Bo;

    2016-01-01

    This paper quantifies the system damping of a offshore meteorological mast supported by a Mono Bucket foundation based on a long-term experimental campaign. The structure is located at Dogger Bank west, North Sea, and equipped with a measurement system monitoring acceleration, strain, inclination...... shows that the total damping ratio of the lowest eigenmode is normally distributed with mean value of 1.11% of critical damping. Linear correlation between the damping ratio and the significant wave height is observed....

  19. A Method to Increase Current Density in a Mono Element Internal Tin Processed Superconductor Utilizing Zr Oxide to Refine Grain Size

    Energy Technology Data Exchange (ETDEWEB)

    Bruce A. Zeitlin, Eric Gregory

    2008-04-07

    The effect of Oxygen on (Nb1Zr)3Sn multifilament conductors manufactured by the Mono Element Internal Tin (MEIT) process was explored to improve the current density by refining the grain size. This followed work first done by General Electric on the Nb3Sn tape process. Techniques to fabricate the more difficult Nb1Zr composites are described and allowed fabrication of long lengths of .254 mm diameter wire from an 88.9 mm diameter billet. Oxygen was incorporated through the use of SnO2 mixed with tin powder and incorporated into the core. These were compared to samples with Ti+Sn and Cu+Sn cores. Heat treatments covered the range of 700 C to 1000 C. Current density vs. H, grain size, and reaction percentages are provided for the materials tested. The Oxygen gave superior results in the temperature range of 815-1000 C. It also stabilized the filament geometry of the array in comparison to the other additions at the higher temperatures. At 815 C a peak in layer Jc yielded values of 2537 A/mm2 at 12 T and 1353 A/mm2 at 15T, 8-22% and 30-73% greater respectively than 700 C values. Results with Oxygen at high temperature show the possibility of high speed continuous reaction of the composite versus the current batch or react in place methods. In general the Ti additions gave superior results at the lower reaction temperature. Future work is suggested to determine if the 815 C reaction temperature can lead to higher current density in high tin (Nb1Zr+Ox)3Sn conductors. A second technique incorporated oxygen directly into the Nb1Zr rods through heat treatment with Nb2O5 at 1100 C for 100 hours in vacuum prior to extrusion. The majority of the filaments reduced properly in the composite but some local variations in hardness led to breakage at smaller diameters.

  20. Aneurysm diameter and proximal aortic neck diameter influence clinical outcome of endovascular abdominal aortic repair : A 4-year EUROSTAR experience

    NARCIS (Netherlands)

    Waasdorp, EJ; de Vries, JPPM; Hobo, R; Leurs, LJ; Buth, J; Moll, FL

    2005-01-01

    Our objective was to evaluate the effect of preoperative aneurysm and aortic neck diameter on clinical outcome after infrarenal abdominal endovascular aneurysm repair (EVAR). Data of patients in the European Collaborators Registry on Stent-Graft Techniques for Abdominal Aortic Aneurysm Repair (EUROS

  1. Modeling of point defects and rare gas incorporation in uranium mono-carbide

    Science.gov (United States)

    Chartier, A.; Van Brutzel, L.

    2007-02-01

    An embedded atom method (EAM) potential has been established for uranium mono-carbide. This EAM potential was fitted on structural properties of metallic uranium and uranium mono-carbide. The formation energies of point defects, as well as activation energies for self migration, have been evaluated in order to cross-check the suitability of the potential. Assuming that the carbon vacancies are the main defects in uranium mono-carbide compounds, the migration paths and energies are consistent with experimental data selected by Catlow[C.R.A. Catlow, J. Nucl. Mater. 60 (1976) 151]. The insertion and migration energies for He, Kr and Xe have also been evaluated with available inter-atomic potentials [H.H. Andersen, P. Sigmund, Nucl. Instr. and Meth. B 38 (1965) 238]. Results show that the most stable defect configuration for rare gases is within uranium vacancies. The migration energy of an interstitial Xe is 0.5 eV, in agreement with the experimental value of 0.5 eV [Hj. Matzke, Science of advanced LMFBR fuels, Solid State Physics, Chemistry and Technology of Carbides, Nitrides and Carbonitrides of Uranium and Plutonium, North-Holland, 1986].

  2. Modeling of dielectric barrier discharge excimer lamp excited by mono polar voltage pulses

    Science.gov (United States)

    Akashi, Haruaki; Oda, Akinori; Sakai, Yosuke

    2007-10-01

    Filametal discharges in Dielectric Barrier Discharge (DBD) excimer lamp excited by mono polar voltage pulses has been simulated using two dimensional fluid model. And the differences of the filament discharges formations between mono polar case and bipolar case [1] have been examined. Xe gas was used and its pressure is 300Torr. Simulated region is 1cm (gap length) x 3cm (radial length). Periodical boundary conditions are assumed for the radial direction boundaries. The both electrodes are covered with dielectrics and their thickness is 0.2cm. Applied voltage is 5kV trapezoid shape with 50% duty ratio waveform and its repetition rate is 200kpps. First a small amount of electron-ion pair is provided in the middle of the gap for initial condition. Then the voltage starts to apply. In the case of bipolar excitation, the discharge starts from one filament (streamer discharge), and finally, 5 filaments are obtained self-consistently. In the case of mono polar case, as first, similar to bipolar case, the discharge starts from one filament, however, only 3 filaments have been obtained. This result is similar to that of 100kHz bipolar voltage case. [1] H. Akashi et al, IEEE Trans. Plasma Science, Vol.33, No.2 (2005) pp.308-309

  3. Evidence that mono-ADP-ribosylation of CtBP1/BARS regulates lipid storage.

    Science.gov (United States)

    Bartz, René; Seemann, Joachim; Zehmer, John K; Serrero, Ginette; Chapman, Kent D; Anderson, Richard G W; Liu, Pingsheng

    2007-08-01

    Mono-ADP-ribosylation is emerging as an important posttranslational modification that modulates a variety of cell signaling pathways. Here, we present evidence that mono-ADP-ribosylation of the transcriptional corepressor C terminal binding protein, brefeldin A (BFA)-induced ADP-ribosylated substrate (CtBP1/BARS) regulates neutral lipid storage in droplets that are surrounded by a monolayer of phospholipid and associated proteins. CtBP1/BARS is an NAD-binding protein that becomes ribosylated when cells are exposed to BFA. Both endogenous lipid droplets and droplets enlarged by oleate treatment are lost after 12-h exposure to BFA. Lipid loss requires new protein synthesis, and it is blocked by multiple ribosylation inhibitors, but it is not stimulated by disruption of the Golgi apparatus or the endoplasmic reticulum unfolded protein response. Small interfering RNA knockdown of CtBP1/BARS mimics the effect of BFA, and mouse embryonic fibroblasts derived from embryos that are deficient in CtBP1/BARS seem to be defective in lipid accumulation. We conclude that mono-ADP-ribosylation of CtBP1/BARS inactivates its repressor function, which leads to the activation of genes that regulate neutral lipid storage.

  4. Performance of nanowire decorated mono- and multi-crystalline Si solarcells

    Science.gov (United States)

    Es, Fırat; Demircioglu, Olgu; Gunoven, Mete; Kulakci, Mustafa; Unalan, Husnu Emrah; Turan, Rasit

    2013-06-01

    Light trapping ability of a solar cell can be improved by the application of various texturing schemes to the surface of the solar cells. For monocrystalline (mono-c) silicon solar cells, this is practically accomplished through pyramid texturing in a hot alkaline solution. For multicrystalline (multi-c) silicon solar cells, texturing is done by continuous oxidation and random etching of silicon from the surface. In this study, we have used metal assisted etching (MAE) technique to form silicon nanowires on the surface of pyramid textured mono-c, flat mono-c and multi-c silicon solar cells with an area of 156 mm×156 mm using standard solar cell processing protocols. It was shown that nanowire texturing causes a dramatic decrease in the reflectivity of the cell surface. Current-voltage (I-V) characteristics revealed that the solar cells with nanowires on top of pyramid texturing exhibit the best performance among all investigated cell types. This may be attributed to combined effect of nanowires and pyramids on the surface.

  5. p-Type Quasi-Mono Silicon Solar Cell Fabricated by Ion Implantation

    Directory of Open Access Journals (Sweden)

    Chien-Ming Lee

    2013-01-01

    Full Text Available The p-type quasi-mono wafer is a novel type of silicon material that is processed using a seed directional solidification technique. This material is a promising alternative to traditional high-cost Czochralski (CZ and float-zone (FZ material. Here, we evaluate the application of an advanced solar cell process featuring a novel method of ion implantation on p-type quasi-mono silicon wafer. The ion implantation process has simplified the normal industrial process flow by eliminating two process steps: the removal of phosphosilicate glass (PSG and the junction isolation process that is required after the conventional thermal POCl3 diffusion process. Moreover, the good passivation performance of the ion implantation process improves Voc. Our results show that, after metallization and cofiring, an average cell efficiency of 18.55% can be achieved using 156 × 156 mm p-type quasi-mono silicon wafer. Furthermore, the absolute cell efficiency obtained using this method is 0.47% higher than that for the traditional POCl3 diffusion process.

  6. Fusion of agarase and neoagarobiose hydrolase for mono-sugar production from agar.

    Science.gov (United States)

    Alkotaini, Bassam; Han, Nam Soo; Kim, Beom Soo

    2017-02-01

    In enzymatic saccharification of agar, endo- and exo-agarases together with neoagarobiose hydrolase (NABH) are important key enzymes for the sequential hydrolysis reactions. In this study, a bifunctional endo/exo-agarase was fused with NABH for production of mono-sugars (D-galactose and 3,6-anhydro-L-galactose) from agar using only one fusion enzyme. Two fusion enzymes with either bifunctional agarase (Sco3476) or NABH (Zg4663) at the N-terminus, Sco3476-Zg4663 (SZ) and Zg4663-Sco3476 (ZS), were constructed. Both fusion enzymes exhibited their optimal agarase and NABH activities at 40 and 35 °C, respectively. Fusions SZ and ZS enhanced the thermostability of the NABH activity, while only fusion SZ showed a slight enhancement in the NABH catalytic efficiency (K cat/K M) from 14.8 (mg/mL)(-1) s(-1) to 15.8 (mg/mL)(-1) s(-1). Saccharification of agar using fusion SZ resulted in 2-fold higher mono-sugar production and 3-fold lower neoagarobiose accumulation when compared to the physical mixture of Sco3476 and Zg4663. Therefore, this fusion has the potential to reduce enzyme production cost, decrease intermediate accumulation, and increase mono-sugar yield in agar saccharification.

  7. Effect of mono-vacancy on transport properties of zigzag carbon- and boron-nitride-nanotube heterostructures

    Science.gov (United States)

    Zhao, P.; Liu, D. S.; Chen, G.

    2013-04-01

    On the basis of first-principles density functional theory and non-equilibrium Green's function technique, we have investigated the effects of a mono-vacancy on the electronic transport properties of the carbon nanotube/boron nitride nanotube heterostructures. The results show that the electronic transport properties are strongly dependent on the position of the mono-vacancy, and the negative differential resistance and rectifying performances can be strengthened or weakened alternately with the position change of the mono-vacancy. Moreover, the performance change is more significant when the mono-vacancy occurs on the carbon nanotube part. These interesting phenomena are explained in terms of the evolution of the transmission spectrum with applied bias combined with molecular projected self-consistent Hamiltonian states analysis.

  8. Influencia de factores culturales en la tenencia de monos aulladores como mascotas y su efecto sobre los individuos en cautiverio

    National Research Council Canada - National Science Library

    Gomez Ruiz, Catalina

    2010-01-01

    ...) como mascotas y los impactos de esta practica sobre los individuos en cautiverio, se analizaron diez casos de monos aulladores que fueron decomisados y remitidos entre septiembre de 2007 y junio...

  9. Highly luminescent mono- and multilayers of immobilized CdTe nanocrystals: controlling optical properties through post chemical surface modification.

    Science.gov (United States)

    Tsuruoka, Takaaki; Takahashi, Rena; Nakamura, Toshihiro; Fujii, Minoru; Akamatsu, Kensuke; Nawafune, Hidemi

    2008-04-14

    The significant fluorescence enhancement of immobilized CdTe nanocrystals through chemical surface modifications is described, enabling us to fabricate stable, highly luminescent thin films and patterns of nanocrystal mono- and mutilayers.

  10. DIRECT ETHOXYLATION OF GLYCEROL MONO OLEATE FROM PALM OIL DERIVATE AS A NOVEL NON-IONIC POLYMERIC SURFACTANT

    Directory of Open Access Journals (Sweden)

    Joddy Arya Laksmono

    2012-01-01

    Full Text Available The work investigates ethoxylation of glycerol mono oleate (GMO performed in the presence of an alkaline catalyst. Glycerol mono oleate applied was derivated from Indonesian palm oil. The reaction was conducted with variation of Glycerol mono oleate : ethylene oxide ratio, temperature, and catalyst concentration. Forier Transform Infra Red (FTIR and Nuclear Magnetic Resonance (NMR analysis showed products with degrees of ethoxylation n=2 and n=3. FTIR analysis of products gave a new peak at 1570 cm-1 supporting that C-O-C bond was formed. New peaks were also observed in 13-C-NMR analysis of run 2 and run 3 with chemical shift of (δ 61.3385; 61.9108; 62.5117; 63.8566; 66.0982; 72.6127 and 61.2172; 63.2393; 65.9100; 72.5201, respectively. Glycerol mono oleate ethoxylated was yielded and could be useful for a novel non-ionic polymeric surfactant.

  11. The synthesis of mono-6-thio-β-cyclodextrin capped CdTe QDs and its interaction with neutral red

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This paper presents a novel method for the synthesis of CdTe quantum dots (QDs) capped with β-cyclodextrin in aqueous solution using both TGA and mono-6-thio-β-CD as stabilizers.The interaction between mono-6-thio-β-CD-CdTe QDs and neutral red (NR) was studied with fluorescence,UV-absorption and the resonance Rayleigh scattering spectrum.When its concentration was over 7.5 × 10-6 mol/L,the neutral red began to aggregate on the surface of the mono-6-thio-β-CD-CdTe QDs,which resulted in the mono-6-thio-β-CD-CdTe QDs particle size increasing,the sharply quenched fluorescence,and the marked increase of RRS intensity.

  12. 分支水平井稳态渗流理论及最优井长%The time-invariant seepage theory and optimal wellbore length of multi-lateral horizontal wells

    Institute of Scientific and Technical Information of China (English)

    曾晓晶; 同登科

    2011-01-01

    针对油藏中分支水平井的稳态渗流问题,基于渗流力学理论,采用全三维方法,导出了油藏稳态渗流与分支水平井井筒流的耦合模型.用改进的Su方法以及一种新方法计算了裸眼完井分支水平井井筒内的压降,分析和比较了井筒内压力和采油指的分布情况;同时,给出了考虑经济因素的分支水平井水平段最优长度的计算方法.结果表明,分支水平井的单个分支内的流动况和水平井近似;由于摩擦因素的影响,分支水平井的水平分支不是越长越好,而是有一个最优值.这些结论可用于实际油藏中支水平井的设计和产能预测.%In terms of the time-invariant seepage of multi-lateral horizontal wells in oil reservoirs, a coupled model of the time-invariant seepage in reservoirs and the wellbore flow in multi-lateral horizontal wells was deduced with the full 3D analytical method based on the filtration mechanic theory. The pressure drop in barefoot completion multi-lateral horizontal wellbores was calculated using the improved Su method and a new approach, and distributions of pressure and productive indices in wellbores were analyzed and compared. At the same time, a computing method with the consideration of economic factors was proposed to optimize the length of the horizontal section for multi-lateral horizontal wells. The results derived from calculations and analyses of some real cases indicated that the flowing status within an individual branch of multi-lateral horizontal wells was similar to that in horizontal wells, the length of lateral branches of multi-lateral horizontal wells is not the longer, the better, but instead, it has an optimal value due to the friction effect. These conclusions are available for designing multi-lateral horizontal wells and forecasting the productivity of this kind of wells.

  13. Symptoms and Immune Markers in Plasmodium/Dengue Virus Co-infection Compared with Mono-infection with Either in Peru.

    Directory of Open Access Journals (Sweden)

    Eric S Halsey

    2016-04-01

    Full Text Available Malaria and dengue are two of the most common vector-borne diseases in the world, but co-infection is rarely described, and immunologic comparisons of co-infection with mono-infection are lacking.We collected symptom histories and blood specimens from subjects in a febrile illness surveillance study conducted in Iquitos and Puerto Maldonado, Peru, between 2002-2011. Nineteen symptoms and 18 immune markers at presentation were compared among those with co-infection with Plasmodium/dengue virus (DENV, Plasmodium mono-infection, and DENV mono-infection. Seventeen subjects were identified as having Plasmodium/DENV co-infection and were retrospectively matched with 51 DENV mono-infected and 44 Plasmodium mono-infected subjects. Those with Plasmodium mono-infection had higher levels of IL-4, IL-6, IL-10, IL-12, IL-13, IL-17A, IFN-γ, and MIP1-α/CCL3 compared with DENV mono-infection or co-infection; those with Plasmodium mono-infection had more cough than those with DENV mono-infection. Subjects with DENV mono-infection had higher levels of TGF-β1 and more myalgia than those with Plasmodium mono-infection. No symptom was more common and no immune marker level was higher in the co-infected group, which had similar findings to the DENV mono-infected subjects.Compared with mono-infection with either pathogen, Plasmodium/DENV co-infection was not associated with worse disease and resembled DENV mono-infection in both symptom frequency and immune marker level.

  14. Symptoms and Immune Markers in Plasmodium/Dengue Virus Co-infection Compared with Mono-infection with Either in Peru

    Science.gov (United States)

    Halsey, Eric S.; Baldeviano, G. Christian; Edgel, Kimberly A.; Vilcarromero, Stalin; Sihuincha, Moises; Lescano, Andres G.

    2016-01-01

    Background Malaria and dengue are two of the most common vector-borne diseases in the world, but co-infection is rarely described, and immunologic comparisons of co-infection with mono-infection are lacking. Methodology and Principal Findings We collected symptom histories and blood specimens from subjects in a febrile illness surveillance study conducted in Iquitos and Puerto Maldonado, Peru, between 2002–2011. Nineteen symptoms and 18 immune markers at presentation were compared among those with co-infection with Plasmodium/dengue virus (DENV), Plasmodium mono-infection, and DENV mono-infection. Seventeen subjects were identified as having Plasmodium/DENV co-infection and were retrospectively matched with 51 DENV mono-infected and 44 Plasmodium mono-infected subjects. Those with Plasmodium mono-infection had higher levels of IL-4, IL-6, IL-10, IL-12, IL-13, IL-17A, IFN-γ, and MIP1-α/CCL3 compared with DENV mono-infection or co-infection; those with Plasmodium mono-infection had more cough than those with DENV mono-infection. Subjects with DENV mono-infection had higher levels of TGF-β1 and more myalgia than those with Plasmodium mono-infection. No symptom was more common and no immune marker level was higher in the co-infected group, which had similar findings to the DENV mono-infected subjects. Conclusions/Significance Compared with mono-infection with either pathogen, Plasmodium/DENV co-infection was not associated with worse disease and resembled DENV mono-infection in both symptom frequency and immune marker level. PMID:27128316

  15. Tunable diameter electrostatically formed nanowire for high sensitivity gas sensing

    Institute of Scientific and Technical Information of China (English)

    Alex Henning; Nandhini Swaminathan; Andrey Godkin; Gil Shalev; Iddo Amit; Yossi Rosenwaks

    2015-01-01

    We report on an electrostatically formed nanowire (EFN)-based sensor with tunable diameters in the range of 16 nm to 46 nm and demonstrate an EFN- based field-effect transistor as a highly sensitive and robust room temperature gas sensor. The device was carefully designed and fabricated using standard integrated processing to achieve the 16 nm EFN that can be used for sensing without any need for surface modification. The effective diameter for the EFN was determined using Kelvin probe force microscopy accompanied by three- dimensional electrostatic simulations. We show that the EFN transistor is capable of detecting 100 parts per million of ethanol gas with bare SiO2.

  16. Angular diameter distances reconsidered in the Newman and Penrose formalism

    CERN Document Server

    Kling, Thomas P

    2016-01-01

    Using the Newman and Penrose spin coefficient (NP) formalism, we provide a derivation of the Dyer-Roeder equation for the angular diameter distance in cosmological space-times. We show that the geodesic deviation equation written in NP formalism is precisely the Dyer-Roeder equation for a general Friedman-Robertson-Walker (FRW) space-time, and then we examine the angular diameter distance to redshift relation in the case that a flat FRW metric is perturbed by a gravitational potential. We examine the perturbation in the case that the gravitational potential exhibits the properties of a thin gravitational lens, demonstrating how the weak lensing shear and convergence act as source terms for the perturbed Dyer-Roeder equation.

  17. Visual function and retinal vessel diameters during hyperthermia in man

    DEFF Research Database (Denmark)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per

    2017-01-01

    laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. RESULTS: The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p ... in cling film, tinfoil and warming blankets. Subsequent cooling was achieved by undressing. Flicker sensitivity (critical flicker fusion frequency) was chosen to assess temporal resolution, while the Freiburg Vision Test was used to determine spatial contrast sensitivity at 1.5 cycles per degree. Scanning...... diameters (CI95 0.96-4.94, p cooling. CONCLUSION: Increased core body temperature was accompanied by improved temporal visual resolution and retinal trunk...

  18. Synthesis and antiprotozoal activity of mono- and bis-uracil isatin conjugates against the human pathogen Trichomonas vaginalis.

    Science.gov (United States)

    Kumar, Kewal; Liu, Nicole; Yang, Donald; Na, Daniel; Thompson, John; Wrischnik, Lisa A; Land, Kirkwood M; Kumar, Vipan

    2015-08-15

    A library of mono- and bis-uracil isatin conjugates were synthesized and subjected for the assessment of their in vitro activity against the protozoal pathogen Trichomonas vaginalis. The structure activity studies (SAR) revealed that the bis-uracil-isatin based conjugates were more effective than their corresponding mono conjugates in inhibiting the growth of T. vaginalis at approximately 10 μM with no visual effect on mammalian cells at the same concentration.

  19. Single-step brazing process for mono-block joints and mechanical testing

    Energy Technology Data Exchange (ETDEWEB)

    Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S. [Politecnico di Torino, Materials Science and Chemical Engineering Dept., Torino (Italy); Merola, M. [ITER International Team, llER Joint Work Site, Cadarache, 13 - St Paul Lez Durance (France)

    2007-07-01

    Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non

  20. Systemic lupus erythematosus patients contain significantly less igm against mono-methylated lysine than healthy subjects.

    Directory of Open Access Journals (Sweden)

    Sha Guo

    Full Text Available Post-translational modifications on proteins are important in biological processes but may create neo-epitopes that induce autoimmune responses. In this study, we measured the serum IgG and IgM response to a set of non-modified or acetyl- and methyl-modified peptides corresponding to residues 1-19 of the histone 3 N-terminal tail in systemic lupus erythematosus (SLE patients and healthy subjects. Our results indicated that the SLE patients and healthy subjects produced antibodies (Abs to the peptides, but the two groups had different Ab isotype and epitope preferences. Abs to the non-modified form, H31-19, were of the IgG isotype and produced by SLE patients. They could not recognize the scrambled H31-19, which contained the same amino acid composition but a different sequence as H31-19. In comparison, healthy subjects in general did not produce IgG against H31-19. However, about 70% of the healthy subjects produced IgM Abs against mono-methylated K9 of H31-19 (H31-19K9me. Our further studies revealed that ε-amine mono-methylated lysine could completely inhibit the IgM binding to H31-19K9me, but lysine had no inhibitory effect. In addition, the IgM Abs could bind peptides containing a mono-methylated lysine residue but with totally different sequences. Thus, mono-methylated lysine was the sole epitope for the IgM. Interestingly, SLE patients had much lower levels of this type of IgM. There was no obvious correlation between the IgM levels and disease activity and the decreased IgM was unlikely caused by medical treatments.We also found that the IgM Abs were not polyreactive to dsDNA, ssDNA, lipopolysaccharide (LPS or insulin and they did not exist in umbilical cord serum, implying that they were not natural Abs. The IgM Abs against mono-methylated lysine are present in healthy subjects but are significantly lower in SLE patients, suggesting a distinct origin of production and special physiological functions.

  1. Possible Recording of the Hilina Pali Excursion in the Mono Basin, California

    Science.gov (United States)

    Coe, R.; Liddicoat, J.

    2012-04-01

    Inclination of about negative 40˚ in basalt from Kilauea volcano, Hawaii (Teanby et al., 2002), that is assigned an age of about 18,000 radiocarbon years (uncorrected)(Coe et al., 1978, after Rubin and Berthold, 1961) and an excursion in northeastern China at Changbaishan Volcano of similar age from Ar40/Ar39 dates (Singer et al., 2011) that was interpreted to be the Blake Subchron (Zhu et al., 2000) using K/Ar (Liu, 1987) and Ar40/39 dates (Lin, 1999), might be recorded as shallow positive inclination in lacustrine siltstone in the bank of Wilson Creek in the Mono Basin, CA. The siltstone was deposited in Pleistocene Lake Russell, of which Mono Lake is the remnant, and was exposed when Wilson Creek was incised as the shoreline of Mono Lake receded (Lajoie, 1968). Basaltic and rhyolitic volcanic ash layers exposed in the bank of the creek are stratigraphic markers that have been important for studies of the Mono Lake Excursion (Denham and Cox, 1971; Liddicoat and Coe, 1979; Liddicoat, 1992; Coe and Liddicoat, 1994) and Pleistocene climate in the U.S. Great Basin (Zimmerman et al., 2006). Those ash layers likewise are useful for locating paleomagnetic directions along strike that might be the negative inclination in Hawaii named the Hilina Pali Excursion (Teanby et al., 2002). The portion of the lacustine section exposed along Wilson Creek that is of interest records waveform Delta in Lund et al. (1988) in Subunit E of Lajoie (1993) that is bracketed by ash layers 12 and 13; in Lajoie (1968), those ash layers are numbered 8 and 7, respectively. About midway in Subunit E, which has a thickness of 1.1 m, the inclination is about 15˚ in four back-to-back horizons that span 8 cm. The subsamples, each 2 cm thick, were treated by either alternating field or thermal demagnetization. The Virtual Geomagnetic Pole (VGP) for the horizon with the shallowest inclination (14.9˚) is 53.8˚ N, 22.7˚ E (n = 6, Alpha-95 = 2.3˚), and the VGPs within waveform Delta when followed

  2. Mono Lake Excursion in Cored Sediment from the Eastern Tyrrhenian Sea

    Science.gov (United States)

    Liddicoat, Joseph; Iorio, Marina; Sagnotti, Leonardo; Incoronato, Alberto

    2013-04-01

    A search for the Laschamp and Mono Lake excursions in cored marine and lacustrine sediment younger than 50,000 years resulted in the discovery of both excursions in the Greenland Sea (73.3˚ N, 351.0˚ E, Nowaczyk and Antanow, 1997), in the North Atlantic Ocean (62.7˚ N, 222.5˚ E, Channell, 2006), in Pyramid Lake in the Lahontan Basin, NV, USA (40.1˚ N, 240.2˚ E, Benson et al., 2008), and in the Black Sea (43.2˚ N, 36.5˚ E, Nowaczyk et al., 2012). The inclination, declination, and relative field intensity during the Mono Lake Excursion (MLE) in the Black Sea sediment matches well the behaviour of the excursion in the Mono Basin, CA, in that a reduction in inclination during westerly declination is soon followed by steep positive inclination when declination is easterly, and relative field intensity increases after a low at the commencement of the excursion (Liddicoat and Coe, 1979). A large clockwise loop of Virtual Geomagnetic Poles (VGPs) at the Black Sea when followed from old to young patterns very well the VGP loop formed by the older portion of the MLE in the Mono Basin (Liddicoat and Coe, 1979). We also searched for the MLE in cored sediment from the eastern Tyrrhenian Sea (40.1˚ N, 14.7˚ E) where the age of the sediment is believed to be about 32,000 years when comparing the susceptibility in the core with the susceptibility in a nearby one that is dated by palaeomagnetic secular variation records, Carbon-14, and numerous tephra layers in the Tyrrhenian Sea sediment (Iorio et al., 2011). In the Tyrrhenian Sea core, called C1067, closely spaced samples demagnetized in an alternating field to100 mT record a shallowing of positive inclination to 48˚ that is followed by steep positive inclination of 82˚ when declination moves rapidly to the southeast. The old to young path of the VGPs in C1067 forms a narrow counter-clockwise loop that reaches 30.3˚ N, 30.8˚ E and that is centered at about 55˚ N, 15˚ E. Although descending to a latitude that is

  3. Range optimization for mono- and bi-energetic proton modulated arc therapy with pencil beam scanning

    Science.gov (United States)

    Sanchez-Parcerisa, Daniel; Kirk, Maura; Fager, Marcus; Burgdorf, Brendan; Stowe, Malorie; Solberg, Tim; Carabe, Alejandro

    2016-11-01

    The development of rotational proton therapy plans based on a pencil-beam-scanning (PBS) system has been limited, among several other factors, by the energy-switching time between layers, a system-dependent parameter that ranges between a fraction of a second and several seconds. We are investigating mono- and bi-energetic rotational proton modulated arc therapy (PMAT) solutions that would not be affected by long energy switching times. In this context, a systematic selection of the optimal proton energy for each arc is vital. We present a treatment planning comparison of four different range selection methods, analyzing the dosimetric outcomes of the resulting treatment plans created with the ranges obtained. Given the patient geometry and arc definition (gantry and couch trajectories, snout elevation) our in-house treatment planning system (TPS) FoCa was used to find the maximum, medial and minimum water-equivalent thicknesses (WETs) of the target viewed from all possible field orientations. Optimal ranges were subsequently determined using four methods: (1) by dividing the max/min WET interval into equal steps, (2) by taking the average target midpoints from each field, (3) by taking the average WET of all voxels from all field orientations, and (4) by minimizing the fraction of the target which cannot be reached from any of the available angles. After the range (for mono-energetic plans) or ranges (for bi-energetic plans) were selected, the commercial clinical TPS in use in our institution (Varian Eclipse™) was used to produce the PMAT plans using multifield optimization. Linear energy transfer (LET) distributions of all plans were also calculated using FoCa and compared among the different methods. Mono- and bi-energetic PMAT plans, composed of a single 180° arc, were created for two patient geometries: a C-shaped target located in the mediastinal area of a thoracic tissue-equivalent phantom and a small brain tumor located directly above the brainstem. All

  4. Consequences of the Continuity of the Monic Integer Transfinite Diameter

    CERN Document Server

    Hilmar, Jan

    2007-01-01

    We consider the problem of determining the monic integer transfinite diameter t_M(I)&=&\\lim_{n\\to\\infty}\\inf_{p_n\\in{\\mathcal M_n}}\\supnorm{p_n}{I}^{1/n} for real intervals of length less than 4. We show the $t_M([0,x])$, as a function in $x>0$, is continuous, therefore disproving two conjectures due to Hare and Smyth. Consequently, for $n>2\\in\

  5. A study of the heated length to diameter effects

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Ho; Baek, Won Pil; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    An analytical and experimental investigation has been performed on the heated length-to-diameter effect on critical heat flux exit conditions. A L/D correction factor is developed by applying artificial neural network and conventional regression techniques to the KAIST CHF data base. In addition, experiment is being performed to validate the developed L/D correction factor with independent data. Assessment shows that the developed correction factor is promising for practical applications. 6 refs., 8 figs. (Author)

  6. Retinal vessel diameter changes induced by transient high perfusion pressure

    Institute of Scientific and Technical Information of China (English)

    Yin-Ying; Zhao; Ping-Jun; Chang; Fang; Yu; Yun-E; Zhao

    2014-01-01

    ·AIM: To investigate the effects of transient high perfusion pressure on the retinal vessel diameter and retinal ganglion cells.·METHODS: The animals were divided into four groups according to different infusion pressure and infusion time(60 mm Hg-3min, 60 mm Hg-5min, 100 mm Hg-3min, 100 mm Hg-5min). Each group consisted of six rabbits. The left eye was used as the experimental eye and the right as a control. Retinal vascular diameters were evaluated before, during infusion, immediately after infusion, 5min, 10 min and 30 min after infusion based on the fundus photographs. Blood pressure was monitored during infusion. The eyes were removed after 24 h.Damage to retinal ganglion cell(RGC) was analyzed by histology.·RESULTS: Retina became whiten and papilla optic was pale during perfusion. Measurements showed significant decrease in retinal artery and vein diameter during perfusion in all of the four groups at the proximal of the edge of the optic disc. The changes were significant in the 100 mm Hg-3min group and 100 mm Hg-5min group compared with 60 mm Hg-3min group(P 1=0.025, P 2=0.000).The diameters in all the groups recovered completely after 30 min of reperfusion. The number of RGC)showed no significant changes at the IOP in 100 mm Hg with5 min compared with contralateral untreated eye(P >0.05).·CONCLUSION: Transient fluctuations during infusion lead to temporal changes of retinal vessels, which could affect the retinal blood circulation. The RGCs were not affected by this transient fluctuation. Further studies are necessary to evaluate the effect of pressure during realtime phacoemusification on retinal blood circulation.

  7. Uncertainty budget for optical coordinate measurements of circle diameter

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertainty...... in Measurement (GUM). Various input quantities such as CCD camera resolution, influence of illuminating system, CMM errors etc. were considered in the model function and experimentally investigated....

  8. Pupil Center as a Function of Pupil Diameter

    DEFF Research Database (Denmark)

    Ahmed, Zaheer; Mardanbegi, Diako; Hansen, Dan Witzner

    2016-01-01

    We investigate the gaze estimation error induced by pupil size changes using simulated data. We investigate the influence of pupil diameter changes on estimated gaze point error obtained by two gaze estimation models. Simulation data show that at wider viewing angles and at small eye......-camera distances, error increases with increasing pupil sizes. The maximum error recorded for refracted pupil images is 2.4° of visual angle and 1.5° for non-refracted pupil projections....

  9. THE CUTWIDTH OF TREES WITH DIAMETER AT MOST 4

    Institute of Scientific and Technical Information of China (English)

    LinYixun

    2003-01-01

    The cutwidth problem for a graph G is to embed G into a path Pn such that the maximum number of overlap edges (i. e. , the congestion) is minimized. It is known that the problem for general graphs is NP-hard while it is polynomially solvable for trees. This paper presents an exact formula for the cutwidth of trees with diameter at most 4. A relation with the bandwidth is discussed as well.

  10. Visual function and retinal vessel diameters during hyperthermia in man.

    Science.gov (United States)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per; Arvidsson, Henrik; Loskutova, Ekaterina; Munch, Inger Christine; Larsen, Michael

    2016-12-21

    To assess the effect of elevated core body temperature on temporal and spatial contrast sensitivity and retinal vessel diameters. The study included 13 healthy volunteers aged 20-37 years. Core body temperature elevation (target +1.1°C) was induced by wrapping the participants in cling film, tinfoil and warming blankets. Subsequent cooling was achieved by undressing. Flicker sensitivity (critical flicker fusion frequency) was chosen to assess temporal resolution, while the Freiburg Vision Test was used to determine spatial contrast sensitivity at 1.5 cycles per degree. Scanning laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p < 0.01), a 10.6-mmHg mean reduction in diastolic blood pressure (p < 0.01), a mean increase in pulse rate of 36.3 bpm (p < 0.0001), a 2.66% improvement in flicker sensitivity (CI95 1.37-3.94, p < 0.001), a 2.80% increase in retinal artery diameters (CI95 1.09-4.51, p < 0.01) and a 2.95% increase in retinal vein diameters (CI95 0.96-4.94, p < 0.01). There was no detectable effect of temperature on spatial contrast sensitivity. All ocular test parameters returned to baseline levels after cooling. Increased core body temperature was accompanied by improved temporal visual resolution and retinal trunk vessel dilation. The results suggest that hyperthermia is associated with enhanced retinal function and increased retinal metabolism. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  11. PREPARATION AND ADSORBABILITY OF DEXTRAN MICROSPHERES WITH UNIFORM DIAMETER

    Institute of Scientific and Technical Information of China (English)

    Ri-sheng Yao; Wen-xia Gao; Jing Sun; Ya-hua You

    2005-01-01

    The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated. The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase. Characteristics of the prepared dextran microspheres were examined with laser light blocking technique, optical microscope and ultraviolet spectrometer. The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution, nearly 92% of them having a diameter of 56.6 μm. In vitro evaluation of adsorbability, wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃. The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g, which is even higher. And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature. The adsorbability is better at lower temperature and higher concentration of methylene blue.

  12. Effects of Pupil Diameter on Light Detection and Temporal Modulation

    Institute of Scientific and Technical Information of China (English)

    Rachel S Li; Andrew W Siu; Johnny C Liyu; Elice C Chan

    2003-01-01

    Purpose: This study compared the effects of pupil variation on light detection and temporal modulation across the central visual field.Methods:Light detection sensitivity (LDS) and low flickering frequency (6Hz) temporal modulation sensitivity (TMS) of 20 young subjects were measured from the central visual field of the right eyes using an automated perimeter (Medmont M600). The measurements were taken under 3 artificial pupils, I.e. 3 mm, 4.3 mm and 6 mm diameters.The sensitivities were grouped and averaged for different retinal eccentricities(3°, 6°, 10° and 15°).Results:TMS and LDS were reduced with increasing retinal eccentricities( P < 0.001)and decreasing pupil diameters( P < 0.001). TMS collected from all pupil diameters were significantly different from each other( P < 0.001). Similarly, LDS under 3 mm pupil was statistically different from those of 4.3 mm and 6 mm(P < 0.003). Comparison of the hills of vision showed that pupil variation resulted in significantly different slopes (P=0.001).The slopes were also found to be significantly different between TMS and LDS (P=0.012).Conclusions: The data showed that dilated pupil resulted in significantly higher sensitivities than those of smaller pupil for both visual functions. The difference in the slopes of hills of vision also suggested that the variation in retinal illumination affected the visual responses differently at various retinal eccentricitities for TMS and LDS.

  13. Effect of conical nanopore diameter on ion current rectification.

    Science.gov (United States)

    Kovarik, Michelle L; Zhou, Kaimeng; Jacobson, Stephen C

    2009-12-10

    Asymmetric nanoscale conduits, such as conical track-etch pores, rectify ion current due to surface charge effects. To date, most data concerning this phenomenon have been obtained for small nanopores with diameters comparable to the electrical double layer thickness. Here, we systematically evaluate rectification for nanopores in poly(ethylene terephthalate) membranes with tip diameters of 10, 35, 85, and 380 nm. Current-voltage behavior is determined for buffer concentrations from 1 mM to 1 M and pHs 3.4 and 6.7. In general, ion current rectification increases with decreasing tip diameter, with decreasing ionic strength, and at higher pH. Surface charge contributes to increased pore conductivities compared to bulk buffer conductivities, though double layer overlap is not necessary for rectification to occur. Interestingly, the 35 nm pore exhibits a maximum rectification ratio for the 0.01 M buffer at pH 6.7, and the 380 nm pores exhibit nearly diodelike current-voltage curves when initially etched and strong rectification after the ion current has stabilized.

  14. Time-delay Cosmography: Increased Leverage with Angular Diameter Distances

    CERN Document Server

    Jee, Inh; Suyu, Sherry H; Huterer, Dragan

    2015-01-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the cosmic microwave background data of Planck improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat $\\Lambda$CDM model by a factor of two. Therefore, previous forec...

  15. Time-delay cosmography: increased leverage with angular diameter distances

    Science.gov (United States)

    Jee, I.; Komatsu, E.; Suyu, S. H.; Huterer, D.

    2016-04-01

    Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used in forecasting cosmographic constraints. In this paper, we show that the cosmological constraints improve significantly when the latter information is also included. Specifically, the angular diameter distance plays a crucial role in breaking the degeneracy between the curvature of the Universe and the time-varying equation of state of dark energy. Using a mock sample of 55 bright quadruple lens systems based on expectations for ongoing/future imaging surveys, we find that adding the angular diameter distance information to the time-delay distance information and the Planck's measurements of the cosmic microwave background anisotropies improves the constraint on the constant equation of state by 30%, on the time variation in the equation of state by a factor of two, and on the Hubble constant in the flat ΛCDM model by a factor of two. Therefore, previous forecasts for the statistical power of time-delay systems were overly pessimistic, i.e., time-delay systems are more powerful than previously appreciated.

  16. Real-time diameter measurement using diffuse light

    Science.gov (United States)

    Luo, Xiaohe; Hui, Mei; Zhu, Qiudong; Wang, Shanshan

    2016-09-01

    A method for on-line rapid determination of the diameter of metallic cylinder is introduced in this paper. Under the radiation of diffuse light, there is a bright area close to the margin of metallic cylinder, and the method of this paper is based on the intensity distribution of the bright area. In this paper, with the radiation by a diffuse plane light with special shape, we present the relation expression of the distance between the peak point and the real edge of the cylinder and the distance between the diffuse light and the pinhole aperture of the camera. With the expression, the diameter of the cylinder to be measured can be calculated. In the experiments, monochromatic LED uniting with ground glass forms the diffuse light source, then the light irradiates the tested cylinder. After the cylinder, we use a lens with a front pinhole stop to choose the light into CMOS, then a computer is used to analyze images and export the measurement results. The measuring system using this method is very easily implemented, so it can realize the on-line rapid measurement. Experimental results are presented for six metallic cylinders with the diameter in 5 18mm range and roughness in Ra- 0.02um, and the precision reaches 3um.

  17. Separation of type and grade in cervical tumours using non-mono-exponential models of diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Winfield, Jessica M.; Collins, David J.; Morgan, Veronica A.; DeSouza, Nandita M. [The Royal Marsden NHS Foundation Trust, MRI Unit, Sutton, Surrey (United Kingdom); The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Orton, Matthew R. [The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Ind, Thomas E.J. [The Royal Marsden NHS Foundation Trust, Gynaecology Unit, London (United Kingdom); Attygalle, Ayoma; Hazell, Steve [The Royal Marsden NHS Foundation Trust, Department of Histopathology, London (United Kingdom)

    2017-02-15

    Assessment of empirical diffusion-weighted MRI (DW-MRI) models in cervical tumours to investigate whether fitted parameters distinguish between types and grades of tumours. Forty-two patients (24 squamous cell carcinomas, 14 well/moderately differentiated, 10 poorly differentiated; 15 adenocarcinomas, 13 well/moderately differentiated, two poorly differentiated; three rare types) were imaged at 3 T using nine b-values (0 to 800 s mm{sup -2}). Mono-exponential, stretched exponential, kurtosis, statistical, and bi-exponential models were fitted. Model preference was assessed using Bayesian Information Criterion analysis. Differences in fitted parameters between tumour types/grades and correlation between fitted parameters were assessed using two-way analysis of variance and Pearson's linear correlation coefficient, respectively. Non-mono-exponential models were preferred by 83 % of tumours with bi-exponential and stretched exponential models preferred by the largest numbers of tumours. Apparent diffusion coefficient (ADC) and diffusion coefficients from non-mono-exponential models were significantly lower in poorly differentiated tumours than well/moderately differentiated tumours. α (stretched exponential), K (kurtosis), f and D* (bi-exponential) were significantly different between tumour types. Strong correlation was observed between ADC and diffusion coefficients from other models. Non-mono-exponential models were preferred to the mono-exponential model in DW-MRI data from cervical tumours. Parameters of non-mono-exponential models showed significant differences between types and grades of tumours. (orig.)

  18. Mono Lake Excursion as a Chronologic Marker in the U.S. Great Basin

    Science.gov (United States)

    Liddicoat, J. C.; Coe, R. S.; Knott, J. R.

    2008-05-01

    Nevada, Utah, and California east of the Sierra Nevada are in the Great Basin physiographic province of western North America. During periods of the Pleistocene, Lake Bonneville and Lake Lahontan covered valleys in Utah and Nevada, respectively, and other lakes such as Lake Russell in east-central California did likewise (Feth, 1964). Now dry except for its remnant, Mono Lake, Lake Russell provides an opportunity to study behavior of Earth's past magnetic field in lacustrine sediments that are exposed in natural outcrops. The sediments record at least 30,000 years of paleomagnetic secular variation (Liddicoat, 1976; Zimmerman et al., 2006) and have been of particular interest since the discovery of the Mono Lake Excursion (MLE) by Denham and Cox (1971) because the field behavior can be documented at numerous sites around Mono Lake (Liddicoat and Coe, 1979, Liddicoat, 1992; Coe and Liddicoat, 1994) and on Paoha Island in the lake. Moreover, there have been recent attempts to date the excursion (Kent et al., 2002, Benson et al., 2003) more accurately and use the age and relative field intensity in paleoclimate research (Zimmerman et al., 2006). It has been proposed that the excursion in the Mono Basin might be older than originally believed (Denham and Cox, 1971; Liddicoat and Coe, 1979) and instead be the Laschamp Excursion (LE), ~ 40,000 yrs B.P. (Guillou et al., 2004), on the basis of 14C and 40Ar/39Ar dates (Kent et al., 2002) and the relative paleointensity record (Zimmerman et al., 2006) for the excursion in the Mono Basin. On the contrary, we favor a younger age for the excursion, ~ 32,000 yrs B.P., using the relative paleointensity at the Mono and Lahontan basins and 14C dates from the Lahontan Basin (Benson et al., 2003). The age of ~ 32,000 yrs B.P. is in accord with the age (32,000-34,000 yrs B.P.) reported by Channell (2006) for the MLE at Ocean Drilling Program (ODP) Site 919 in the Irminger Basin in the North Atlantic Ocean, which contains as well an

  19. Mono(2-ethylhexyl)phthalate and mono-n-butyl phthalate activation of peroxisome proliferator activated-receptors alpha and gamma in breast.

    Science.gov (United States)

    Venkata, Nagaraj Gopisetty; Robinson, Jodie A; Cabot, Peter J; Davis, Barbara; Monteith, Greg R; Roberts-Thomson, Sarah J

    2006-06-01

    The phthalates di(2-ethylhexyl)phthalate (DEHP) and di-n-butyl phthalate (DBP) are environmental contaminants with significant human exposures. Both compounds are known reproductive toxins in rodents and DEHP also induces rodent hepatocarcinogenesis in a process believed to be mediated via the peroxisome proliferator-activated receptor alpha (PPARalpha). DEHP and DBP are metabolised to their respective monoesters, mono-(2-ethylhexyl)phthalate (MEHP) and mono-n-butyl phthalate (MBP), which are the active metabolites. MEHP also activates another member of the PPAR subfamily, PPARgamma. The effects of PPARalpha and PPARgamma activation in human breast cells appears to be opposing; PPARalpha activators in breast cells cause an increase in proliferation, while PPARgamma activation in breast cells is associated with differentiation and an inhibition of cell proliferation. Further to this the activation of the PPARs is cell and ligand specific, suggesting the importance of examining the effect of MEHP and MBP on the activation of PPARalpha, PPARbeta and PPARgamma in human breast. We used the common model of human breast cancer MCF-7 and examined the ability of MEHP and MBP to activate human PPARs in this system. The ability of MBP and MEHP to block PPAR responses was also assessed. We found that both human PPARalpha and PPARgamma were activated by MEHP whereas MEHP could not activate PPARbeta. MBP was unable to activate any PPAR isoforms in this breast model, despite being a weak peroxisome proliferator in liver, although MBP was an antagonist for both PPARgamma and PPARbeta. Our results suggest that the toxicological consequences of MEHP in the breast could be complex given the opposing effects of PPARalpha and PPARgamma in human breast cells.

  20. Research on the Principles of Wellbore Multiphase Flow During Sour Gas Influx%酸性天然气侵入井筒多相流动规律研究

    Institute of Scientific and Technical Information of China (English)

    万立夫; 李根生; 迟焕鹏; 宋先知; 王海柱

    2012-01-01

    The mathematics model of wellbore multiphase flow after sour gas influx is established. The paper is comprehensively based on the application of pressure drop model and heat transfer model for two phases flow in wellbore, coupling the wellbore unsteady flow and formation seepage, and the mutual reaction ( chemical reaction and solubility) between sour gas and water-based drilling fluid into consideration. The pressure distribution in wellbore is calculated by numerical method with different components ( methane + carbon dioxide, methane + hydrogen sulfide) when drilling the same formation. The results indicates that the chemical reaction can be ignored. The solubility of carbon dioxide or hydrogen sulfide in the water-based drilling fluid is very remarkable. When the sour gas is near the wellhead, the solubility is decreased sharply. The density of sour gas has a sharp change near the wellhead. The higher he mole fraction of carbon dioxide and hydrogen sulfide of sour gas is, the shorter of distance near the wellhead is. The higher he mole fraction of carbon dioxide and hydrogen sulfide of sour gas is, the smaller change of pressure in the bottom hole pressure is. So that we shouldn' t judge the overflow lever according to the drop of bottom hole pressure.%在综合应用井筒两相流压降和传热模型的基础上,考虑地层渗流与井筒耦合,考虑了钻井液和侵入酸性流体的基本物性参数与井筒温度压力的耦合作用,酸性天然气与水基钻井液间的相互作用(化学反应和溶解),建立酸性天然气侵入井筒多相流计算模型.通过数值计算分析,钻遇相同地层条件下,不同组分(甲烷+二氧化碳,甲烷+硫化氢)两类酸性天然气藏的环空压力等变化规律.结果表明,酸性天然气与水基钻井液化学反应消耗酸性天然气质量流量很小,可忽略.而井筒内溶解度较大,酸性天然气在近井口处由于溶解度迅速降低,气体密度发生突变,且二氧化碳和

  1. Effects of Diameter on Initial Stiffness of P-Y Curves for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo; Augustesen, Anders Hust

    2010-01-01

    For offshore wind turbines, monopile foundations with diameters of 4–6m are often employed. The Winkler model approach, where the soil resistance is modelled as uncoupled springs with spring stiffness’ given by p-y curves, is traditionally employed for the design of monopiles. However, this metho...... analyses by means of the commercial program FLAC3D incorporating a Mohr-Coulomb failure criterion. The numerical model is validated with laboratory tests in a pressure tank at Aalborg University....

  2. Wellbore Wall Stress Analysis around Failure Casing in Consideration of Fluid Seepage%考虑渗流作用的套管错断口井壁围岩应力场分析

    Institute of Scientific and Technical Information of China (English)

    艾池; 刘国勇; 刘顺利; 隋杨; 赵万春

    2011-01-01

    考虑井壁周围岩体中流体的渗流作用,建立了套管错断口井壁岩体的平衡微分方程.然后按照损伤程度的不同将错断口井壁岩体划分为不同的区域(失稳破坏区、损伤区、弹性区),考虑不同区域内岩石材料参数的不同,分析了错断口周围岩体各个区域内的应力分布规律,确定了失稳破坏区和损伤区的半径,并在此基础上得到了岩体发生失稳破坏和损伤时的临界应力条件,从而为套管错断后井壁稳定性的研究和错断口吐岩块现象的预防提供了理论依据.%The balanced differential equation of wellbore wall is built around failure casing considering fluid seepage. The area around failure casing is divided into different areas (unstable failure zone, damaged zone, elastic zone) according to the degree of damage, their stress distribution were obtained with consideration of variations of rock properties in different areas. The radius of unstable failure zone and damaged zone are determined. Critical stresses of rock failure and damage are obtained which provides a theoretical basis for the wellbore stability investigation and casing failure prevention.

  3. Prevalence, Risk Factors, and Treatment Outcomes of Isoniazid- and Rifampicin- Mono-Resistant Pulmonary Tuberculosis in Lima, Peru

    Science.gov (United States)

    Villegas, Leonela; Huaman, Moises A.; Van der Stuyft, Patrick; Gotuzzo, Eduardo; Seas, Carlos

    2016-01-01

    Background Isoniazid and rifampicin are the two most efficacious first-line agents for tuberculosis (TB) treatment. We assessed the prevalence of isoniazid and rifampicin mono-resistance, associated risk factors, and the association of mono-resistance on treatment outcomes. Methods A prospective, observational cohort study enrolled adults with a first episode of smear-positive pulmonary TB from 34 health facilities in a northern district of Lima, Peru, from March 2010 through December 2011. Participants were interviewed and a sputum sample was cultured on Löwenstein-Jensen (LJ) media. Drug susceptibility testing was performed using the proportion method. Medication regimens were documented for each patient. Our primary outcomes were treatment outcome at the end of treatment. The secondary outcome included recurrent episodes among cured patients within two years after completion of the treatment. Results Of 1292 patients enrolled, 1039 (80%) were culture-positive. From this subpopulation, isoniazid mono-resistance was present in 85 (8%) patients and rifampicin mono-resistance was present in 24 (2%) patients. In the multivariate logistic regression model, isoniazid mono-resistance was associated with illicit drug use (adjusted odds ratio (aOR) = 2.10; 95% confidence interval (CI): 1.1–4.1), and rifampicin mono-resistance was associated with HIV infection (aOR = 9.43; 95%CI: 1.9–47.8). Isoniazid mono-resistant patients had a higher risk of poor treatment outcomes including treatment failure (2/85, 2%, p-value<0.01) and death (4/85, 5%, p<0.02). Rifampicin mono-resistant patients had a higher risk of death (2/24, 8%, p<0.01). Conclusion A high prevalence of isoniazid and rifampicin mono-resistance was found among TB patients in our low HIV burden setting which were similar to regions with high HIV burden. Patients with isoniazid and rifampicin mono-resistance had an increased risk of poor treatment outcomes. PMID:27045684

  4. Piston diameter in stapes surgery. Does it have a bearing?

    Directory of Open Access Journals (Sweden)

    Neha Gupta

    2014-01-01

    Full Text Available Aims and Objectives: This prospective randomized controlled trial was done to study the effect of piston diameter on hearing outcomes after stapedotomy. Materials and Methods: All the patients diagnosed to have otosclerosis were included in the study. A total of 52 patients were studied ranging in age from 18 to 50 years. The subjects were randomized into two groups, that is, 0.4 mm piston (group A and 0.6 mm piston (group B. The subjects were taken up for small fenestra stapedotomy using either a 0.4 or 0.6 mm piston. The main outcome measures were hearing improvement, air-bone gap closure, and overclosure of air-bone gap. Results: There was no statistical difference in hearing improvement in two different piston diameters, 0.4 and 0.6 mm at speech frequencies. In group A, the air-bone gap improvement in the third follow-up was not significant (P > 0.05, whereas group B showed a statistically significant improvement (P = 0.003. The mean overclosure of air-bone gap was better in patients with 0.4 mm piston at speech frequencies and also at 250 Hz. Significantly, overclosure of air-bone gap at higher frequencies (4 and 8 KHz was seen only with a smaller sized piston. (0.4 mm. Discussion: We analyzed the effect of piston diameter on the hearing results after small fenestra stapedotomy by using similar surgical procedure and similar prosthesis in all patients. Conclusion: There is evidence to suggest that 0.4 mm piston may be better suited for providing optimum hearing results.

  5. A solar cycle lengthwise series of solar diameter measurements

    Science.gov (United States)

    Penna, J. L.; Andrei, A. H.; Boscardin, S. C.; Neto, E. Reis; d'Ávila, V. A.

    2010-02-01

    The measurements of the solar photospheric diameter rank among the most difficult astronomic observations. Reasons for this are the fuzzy definition of the limb, the SNR excess, and the adverse daytime seeing condition. As a consequence there are very few lengthy and consistent time series of such measurements. Using modern techniques, just the series from the IAG/USP and from Calern/OCA span more than one solar cycle. The Rio de Janeiro Group observations started in 1997, and therefore in 2008 one complete solar cycle time span can be analyzed. The series shares common principles of observation and analysis with the ones afore mentioned, and it is complementary on time to them. The distinctive features are the larger number of individual points and the improved precision. The series contains about 25,000 single observations, evenly distributed on a day-by-day basis. The typical error of a single observation is half an arc-second, enabling us to investigate variations at the expected level of tens of arc-second on a weekly basis. These features prompted to develop a new methodology for the investigation of the heliophysical scenarios leading to the observed variations, both on time and on heliolatitude. The algorithms rely on running averages and time shifts to derive the correlation and statistical incertitude for the comparison of the long term and major episodes variations of the solar diameter against activity markers. The results bring support to the correlation between the diameter variation and the solar activity, but evidentiating two different regimens for the long term trend and the major solar events.

  6. Mesiodistal crown diameters of permanent dentition in schoolchildren from Lima

    OpenAIRE

    Pineda-Mejia, Martha; Departamento Académico de Estomatología Rehabilitadora, Facultad Odontología de la Universidad Nacional Mayor de San Marco, Perú.; Petkova- Gueorguieva, Marieta; Facultad Odontología de la Universidad Nacional Mayor de San Marcos.

    2015-01-01

    The purpose of this study was to determine the size of mesiodistal diameters of permanent teeth in a school population of the city of Lima, to analyze the differences between homologous teeth, sexual dimorphism of permanent teeth as well as the degree of variability of the measurements. Methodology: The study was conducted on 400 students of mestizos (200 men and 200 women) 10 to 12 years, from three schools in the districts of la Victoria and Barrios Altos, Lima city. The procedure was perfo...

  7. Economic strategies of plant absorptive roots vary with root diameter

    Science.gov (United States)

    Kong, D. L.; Wang, J. J.; Kardol, P.; Wu, H. F.; Zeng, H.; Deng, X. B.; Deng, Y.

    2016-01-01

    Plant roots typically vary along a dominant ecological axis, the root economics spectrum, depicting a tradeoff between resource acquisition and conservation. For absorptive roots, which are mainly responsible for resource acquisition, we hypothesized that root economic strategies differ with increasing root diameter. To test this hypothesis, we used seven plant species (a fern, a conifer, and five angiosperms from south China) for which we separated absorptive roots into two categories: thin roots (thickness of root cortex plus epidermis perspective on our understanding of the root economics spectrum.

  8. On the Connectedness and Diameter of a Geometric Johnson Graph

    CERN Document Server

    Bautista-Santiago, Crevel; Fabila-Monroy, Ruy; Flores-Peñaloza, David; González-Aguilar, Hernán; Lara, Dolores; Sarmiento, Eliseo; Urrutia, Jorge

    2012-01-01

    Let $P$ be a set of $n$ points in general position in the plane. A subset $I$ of $P$ is called an \\emph{island} if there exists a convex set $C$ such that $I = P \\cap C$. In this paper we define the \\emph{generalized island Johnson graph} of $P$ as the graph whose vertex consists of all islands of $P$ of cardinality $k$, two of which are adjacent if their intersection consists of exactly $l$ elements. We show that for large enough values of $n$, this graph is connected, and give upper and lower bounds on its diameter.

  9. A Study of Spiral Tap with Large Diameter

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The design and manufacture of spiral tap yet are in r esearch stage at present. This paper mainly introduces how to calculate its geom etric parameters and scientific selection of them with vector method. In additio n, an empiric formula of the tool life of spiral tap with large diameter is esta blished by method of correlation. The practice of design, manufacture and applying proves the advantage of spiral tap by the comparison between the spiral tap and common tap with same size. In the application of...

  10. Impact damage in small diameter graphite/epoxy composite struts

    Science.gov (United States)

    Chen, G.-S.; Bidinger, G. M.; Cho, S.; Lou, M. C.

    1992-01-01

    An investigation was performed to study impact induced damage in small-diameter struts made of a composite material with a brittle matrix system. The major focus is on characterizing the impact behavior associated with the barely visible damage. An experimental procedure including ultrasonic inspection, instrumented impact testing, and delamination buckling and residual strength measurements is presented. From the ultrasonic inspection, it is found that for the strut specimens under investigation, the impact energy level for barely visible damage threshold is above that of the internal damage threshold. A 60- to 65-percent reduction in compressive strength was typical for struts subjected to the barely visible impact damage threshold.

  11. Twist Neutrality and the Diameter of the Nucleosome Core Particle

    DEFF Research Database (Denmark)

    Bohr, Jakob; Olsen, Kasper

    2012-01-01

    The diameter of the nucleosome core particle is the same for all the eukaryotes. Here we discuss the possibility that this selectiveness is consistent with a propensity for twist neutrality, in particular, for the double helical DNA to stay rotationally neutral when strained. Reorganization of DNA...... cannot be done without some level of temporal tensile stress, and as a consequence chiral molecules, such as helices, will twist under strain. The requirement that the nucleosome, constituting the nucleosome core particle and linker DNA, has a vanishing strain-twist coupling leads to a requirement...

  12. Aharonov—Bohm Oscillations in Small Diameter Bi Nanowires

    Science.gov (United States)

    Konopko, L.

    The Aharonov-Bohm effect (AB) exists in cylindrical wires as the magnetoresistance (MR) oscillations with a period ΔB that is proportional to Φ0 / S, where Φ0 = h / e is the flux quantum and S is the wire cross section. The AB-type longitudinal MR oscillations with period ΔB = Φ0 / S caused by electrons undergoing continuous grazing incidence at the wire wall have been observed previously at 4.2 K in single bismuth nanowires with a diameter 0. 2 Spivak theory.

  13. Note: Computer controlled rotation mount for large diameter optics

    CERN Document Server

    Rakonjac, Ana; Deb, Amita B; Kjærgaard, Niels

    2012-01-01

    We describe the construction of a motorized optical rotation mount with a 40 mm clear aperture. The device is used to remotely control the power of large diameter laser beams for a magneto-optical trap (MOT). A piezo-electric ultrasonic motor on a printed circuit board (PCB) provides rotation with a precision better than 0.03 deg and allows for a very compact design. The rotation unit is controlled from a computer via serial communication, making integration into most software control platforms straightforward.

  14. Escitalopram tolerability as mono- versus augmentative therapy in patients with affective disorders: a naturalistic study

    Directory of Open Access Journals (Sweden)

    Dell'Osso B

    2013-02-01

    Full Text Available Bernardo Dell’Osso, Chiara Arici, Cristina Dobrea, Giulia Camuri, Beatrice Benatti, A Carlo AltamuraUniversity of Milan, Department of Psychiatry, Fondazione IRCSS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, ItalyBackground: Escitalopram is a selective serotonin reuptake inhibitor, widely used in the treatment of affective disorders. The purpose of this study was to examine its safety and tolerability, as mono- versus augmentative therapy, in a group of patients with affective disorders.Materials and methods: The sample consisted of 131 patients suffering from different affective disorders, including major depressive disorder, bipolar disorder, and generalized anxiety disorder, who received escitalopram for at least 4 weeks. Data were analyzed on the basis of mono- versus augmentative therapy, as well as age, gender, mean daily dosage, and patterns of combination therapy.Results: Sixty-seven (51.1% patients were treated with monotherapy (mean dose of 11.76 mg/day and 64 (48.9% with augmentative escitalopram (mean dose of 12.81 mg/day. The mean duration of escitalopram treatment was 14 months. The most frequently combined compounds were: other antidepressants (36.5%, mood stabilizers (33.4%, and atypical antipsychotics (30.1%. Side effects were reported in 5.3% of the total sample and the most common were insomnia (2.3%, nausea (2.3%, and dizziness (0.8%. No significant difference, in terms of tolerability, in mono- versus augmentative therapy groups was found. In addition, neither age nor gender was significantly correlated with a greater presence of side effects. Finally, no significant correlation between dosage and side effects was observed.Conclusion: Over a 14-month observation period, escitalopram, either as monotherapy or an augmentative treatment, was found to be well tolerated in a large sample of patients with affective disorders, with an overall low rate of side effects.Keywords: affective disorders, escitalopram

  15. New ruthenium nitrosyl pincer complexes bearing an O2 ligand. Mono-oxygen transfer.

    Science.gov (United States)

    Fogler, Eran; Efremenko, Irena; Gargir, Moti; Leitus, Gregory; Diskin-Posner, Yael; Ben-David, Yehoshoa; Martin, Jan M L; Milstein, David

    2015-03-02

    We report on Ru((II))(μ(2)-O2) nitrosyl pincer complexes that can return to their original Ru(0) state by reaction with mono-oxygen scavengers. Potential intermediates were calculated by density functional theory (DFT) and a mechanism is proposed, revealing a new type of metal-ligand cooperation consisting of activation of the O2 moiety by both the metal center and the NO ligand. Reaction of the Ru(0) nitrosyl complex 1 with O2 quantitatively yielded the crystallographically characterized Ru((II)) (μ(2)-O2) nitrosyl complex 2. Reaction of 2 with the mono-oxygen scavengers phosphines or CO gave the Ru(0) complex 1 and phosphine oxides, or the carbonyl complex 3 (1 trapped by CO) and CO2, respectively. Reaction of 2 with 1 equiv of phosphine at room temperature or -40 °C resulted in immediate formation of half an equivalent of 1 and 1 equiv of phosphine oxide, while half an equivalent of 2 remained unchanged. Overnight reaction at room temperature of 2 with excess CO (≥3 equiv) resulted in 3 and CO2 gas as the only products. Reaction of 1 with 1 equiv of mono-oxygen source (dioxirane) at -78 °C yielded the Ru((II))(μ(2)-O2) complex 2. Similarly, reaction of the Ru(0) dearomatized complex 4 with O2 led to the crystallographicaly characterized Ru((II))(μ(2)-O2) complex 5. Further reaction of 5 with mono-oxygen scavengers (phosphines or CO) led to the Ru(0) complex 4 and phosphine oxides or complex 6 (4 trapped by CO) and CO2. When instead only 1 equiv of 5 was reacted with 1 equiv of phosphine at room temperature, immediate formation of half an equivalent of 4 and 1 equiv of phosphine oxide took place, while half an equivalent of 5 remained unchanged. When 5 reacted with an excess of CO (≥3 equiv), complex 6 and CO2 gas were the only products obtained. DFT studies indicate a new mode of metal-ligand cooperation involving the nitrosyl ligand in the oxygen transfer process.

  16. Electron impact single ionization of mono- and di-positive ions

    Indian Academy of Sciences (India)

    M Alfaz Uddin; A K F Haque; M S Mahbub; K R Karim; A K Basak

    2006-06-01

    The electron impact ionization cross-sections of mono- and di-positive ionic targets are calculated using a second version of the modified binary-encounter-dipole (MBED) model, previously reported [M A Uddin et al, J. Phys. B37, 1909 (2004)]. The present version differs from the previous one in the scale factor of the Burgess denominator and is applicable to targets with charges = 1 and 2. The MBED in the present form is found to work well for 11 ionic targets ranging from Be+ to K+ and complements its previous version valid for targets with > 2.

  17. Polyelectrolyte Properties in Mono and Multi-Valent Ionic Media: Brushes and Complex Coacervates

    Science.gov (United States)

    Farina, Robert M.

    Materials composed of polyelectrolytes have unique and interesting physical properties resulting primarily from their charged monomer segments. Polyelectrolytes, which exist in many different biological and industrial forms, have also been shown to be highly responsive to external environmental changes. Here, two specific polyelectrolyte systems, brushes and complex coacervates, are discussed in regards to how their properties can be tailored by adjusting the surrounding ionic environment with mono and multi-valent ions. End-tethered polyelectrolyte brushes, which constitute an interesting and substantial portion of polyelectrolyte applications, are well known for their ability to provide excellent lubrication and low friction when coated onto surfaces (e.g. articular cartilage and medical devices), as well as for their ability to stabilize colloidal particles in solution (e.g. paint and cosmetic materials). These properties have been extensively studied with brushes in pure mono-valent ionic media. However, polyelectrolyte brush interactions with multi-valent ions in solution are much less understood, although highly relevant considering mono and multi-valent counterions are present in most applications. Even at very low concentrations of multi-valent ions in solution, dramatic polyelectrolyte brush physical property changes can occur, resulting in collapsed chains which also adhere to one another via multi-valent bridging. Here, the strong polyelectrolyte poly(sodium styrene sulfonate) was studied using the Surface Forces Apparatus (SFA) and electrochemistry in order to investigate brush height and intermolecular interactions between two brushes as a function of multi-valent counterion population inside a brush. Complex coacervates are formed when polyanions and polycations are mixed together in proper conditions of an aqueous solution. This mixing results in a phase separation of a polymer-rich, coacervate phase composed of a chain network held together via

  18. Transient heating and evaporation of moving mono-component liquid fuel droplets

    DEFF Research Database (Denmark)

    Yin, Chungen

    2016-01-01

    This paper presents a complete description of a model for transient heating and evaporation of moving mono-component liquid fuel droplets. The model mainly consists of gas phase heat and mass transfer analysis, liquid phase analysis, and droplet dynamics analysis, which address the interaction...... between the moving droplets and free-stream flow, the flow and heat and mass transfer within the droplets, and the droplet dynamics and size, respectively. For the liquid phase analysis, the droplets are discretized into a number of control volumes along the radial, polar and azimuthal directions, on each...

  19. Primary studies of trace quantities of green vegetation in Mono Lake area using 1990 AVIRIS data

    Science.gov (United States)

    Chen, Zhi-Kang; Elvidge, Chris D.; Groeneveld, David P.

    1992-01-01

    Our primary results in Jasper Ridge Biological Preserve indicate that high spectral resolution Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data may provide a substantial advantage in vegetation, based on the chlorophyll red edge feature from 700-780 nm. The chlorophyll red edge was detected for green vegetation cover as low as 4.8 percent. The objective of our studies in Mono Lake area is to continue the experiments performed in Jasper Ridge and to examine the persistence of red edge feature of trace quantities of green vegetation for different plant communities with non-uniform soil backgrounds.

  20. The effect of the polycrystalline furnace in Mono -like growth process

    Institute of Scientific and Technical Information of China (English)

    Li Liu; Zhenzhen Yao; Yan Feng Ning; Xie Min Peng

    2015-01-01

    In this work,we found that the polycrystalline furnace of the thermal field simulation,which has a very important role in this class the growth of monocrystalline silicon.The software is Fluent.Polycrystalline furnace thermal field change process is closely related to the nucleation.we have improved the ration of the grain crystal,and reduce the height of the seed crystal.It is proved that the electrical of the mono like wafer is rather perfect,and the efficiency of the cell is improved greatly.The simulation cal-culation is well agree with the experimental results.