Artículos de revistas: "KT boundary"

1

Ekdale, A. A. y Wolfgang Stinnesbeck. "Trace Fossils in Cretaceous-Tertiary (KT) Boundary Beds in Northeastern Mexico: Implications for Sedimentation during the KT Boundary Event". PALAIOS 13, n.º 6 (diciembre de 1998): 593. http://dx.doi.org/10.2307/3515350.

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2

Rho, Mina, Mo Zhou, Xiang Gao, Sun Kim, Haixu Tang y Michael Lynch. "Independent Mammalian Genome Contractions Following the KT Boundary". Genome Biology and Evolution 1 (1 de enero de 2009): 2–12. http://dx.doi.org/10.1093/gbe/evp007.

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3

Chen, Kongtao, David J. Srolovitz y Jian Han. "Grain-boundary topological phase transitions". Proceedings of the National Academy of Sciences 117, n.º 52 (14 de diciembre de 2020): 33077–83. http://dx.doi.org/10.1073/pnas.2017390117.

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The formation and migration of disconnections (line defects constrained to the grain boundary [GB] plane with both dislocation and step character) control many of the kinetic and dynamical properties of GBs and the polycrystalline materials of which they are central constituents. We demonstrate that GBs undergo a finite-temperature topological phase transition of the Kosterlitz–Thouless (KT) type. This phase transition corresponds to the screening of long-range interactions between (and unbinding of) disconnections. This phase transition leads to abrupt changes in the behavior of GB migration, GB sliding, and roughening. We analyze this KT transition through mean-field theory, renormalization group theory, and kinetic Monte Carlo simulations and examine how this transition affects microstructure-scale phenomena such as grain growth stagnation, abnormal grain growth, and superplasticity.

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4

Premovic, Pavle, Nikola Nikolic, Ivana Tonsa, Dejan Dulanovic y Mirjana Pavlovic. "Cretaceous-tertiary boundary layer at Stevns Klint (Denmark): Copper and copper(II) porphyrins". Journal of the Serbian Chemical Society 64, n.º 5-6 (1999): 349–58. http://dx.doi.org/10.2298/jsc9906349p.

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High concentrations (up to 4000 ppm) of copper(II) porphyrins have been detected in the kerogen of the Cretaceous/Tertiary (KT) boundary informal type sediment, the Fish Clay, at Stevns Klint, Denmark. These pigments have also been found in the Danish KT sediment at Nye Kl?v, which is about 300 km away from Stevns Klint. However, copper(II) porphyrins cannot be detected in the Danich boundary rock of the Dania site, which is separated from Stevns Klint by about 200 km. It is proposed that the kerogen copper(II) porphyrins are derived from humic materials of terrestrial (peat/soil) sources already enriched with these compounds, which were redeposited in the Danish KT boundary Basin. In addition, our results show that the kerogen copper(II) porphyrins are present, for comparison, in the Permian Kupferschiefer shale from Poland. The amounts are comparable to those in the Fish Clay kerogen. To our opinion, the same processes responsible for the kerogen copper(II) porphyrin enrichment have occurred in the Stevns Klint KT boundary sediment and in the Kupferschiefer.

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5

Evans, Robert. "Kafka, New Orleans, the OARs and the KT Boundary". Healthcare Policy | Politiques de Santé 1, n.º 2 (15 de enero de 2006): 14–20. http://dx.doi.org/10.12927/hcpol.2006.17871.

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6

OLDS, Peter, Mathew E. SANBORN, Tim TEAGUE y Qingzhu YIN. "KT Boundary Chromites Determined to be Terrestrial: Cr Isotopic Evidence for Excavation and Ejection of Mafic/Ultramafic Rocks by the KT Boundary Impact". Acta Geologica Sinica - English Edition 91, s1 (mayo de 2017): 26–27. http://dx.doi.org/10.1111/1755-6724.13163.

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7

Premovic, Pavle. "Cretaceous-Tertiary boundary deposits in Denmark: A diachroneity". Journal of the Serbian Chemical Society 69, n.º 7 (2004): 555–61. http://dx.doi.org/10.2298/jsc0407555p.

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The lateral distribution of predominantly terrestrial kerogen or humics enriched with copper(II) porphyrins (Cu-P) across the Danish marine basin implies that the alleged Cretaceous-Tertiary (KT) boundary deposits in western Denmark (at the Nye Kl?v/Dania locations)were probably formed by erosion/emplacement of the boundary clay (Fiskeler) in eastern Denmark by marine currents, as originally proposed by Hulteberg.1,2.

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8

Premovic, Pavle, Bratislav Todorovic, Nikola Nikolic, Mirjana Pavlovic, Dragan Djordjevic y Dejan Dulanovic. "Geochemistry of Ni in the Cretaceous-Tertiary succession Fiskeler (Fish Clay) at Stevns Klint (Denmark): cheto-smectite of the black marl". Journal of the Serbian Chemical Society 71, n.º 6 (2006): 639–59. http://dx.doi.org/10.2298/jsc0606639p.

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The Cretaceus-Tertiary (KT) boundary at Stevns Klint (the H?jerup succession), Fiskeler, consists of a thin red clay layer overlain by a thick one of black marl. These two layers are made up mainly from cheto-smectite and biogenic calcite. The black marl shows an enhanced concentration of Ni (655 ppm) within its smectite fraction. Additionally, its carbonate fraction also shows an enhanced concentration of Ni (245 ppm). It is reasoned that these enrichments represent a sudden and rapid input of high amounts of Ni into the late Cretaceus seawater at Stevns Klint. The ultimate source of Ni in both the carbonate and smectite fractions of the black marl was probably impact fallout, produced by the KT asteroidal impact, deposited on the nearby soil and leached by the (acid) surface waters. The geochemistry of the Ni supports the hypothesis that the smectite of this marl most likely has a local (marine or terrestrial) provenance and was probably redeposited, after its formation, from the original site to its present location at the KT boundary.

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9

Sun, Dazhi, Xianling Dong y Yongling Wang. "Temperature dependence of Kt, in piezoelectric ceramics near F-AF phase boundary". Ferroelectrics Letters Section 15, n.º 5-6 (junio de 1993): 121–26. http://dx.doi.org/10.1080/07315179308204248.

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10

Stinnesbeck, W., G. Keller, T. Adatte, D. Stuben, U. Kramar, Z. Berner, C. Desremeaux y E. Moliere. "Beloc, Haiti, revisited: multiple events across the KT boundary in the Caribbean". Terra Nova 11, n.º 6 (10 de diciembre de 1999): 303–10. http://dx.doi.org/10.1046/j.1365-3121.1999.00263.x.

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11

Ahern, Kyle, Mark A. Bourassa, Robert E. Hart, Jun A. Zhang y Robert F. Rogers. "Observed Kinematic and Thermodynamic Structure in the Hurricane Boundary Layer during Intensity Change". Monthly Weather Review 147, n.º 8 (17 de julio de 2019): 2765–85. http://dx.doi.org/10.1175/mwr-d-18-0380.1.

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Abstract The axisymmetric structure of the inner-core hurricane boundary layer (BL) during intensification [IN; intensity tendency ≥20 kt (24 h)−1, where 1 kt ≈ 0.5144 m s−1], weakening [WE; intensity tendency <−10 kt (24 h)−1], and steady-state [SS; the remainder] periods are analyzed using composites of GPS dropwindsondes from reconnaissance missions between 1998 and 2015. A total of 3091 dropsondes were composited for analysis below 2.5-km elevation—1086 during IN, 1042 during WE, and 963 during SS. In nonintensifying hurricanes, the low-level tangential wind is greater outside the radius of maximum wind (RMW) than for intensifying hurricanes, implying higher inertial stability (I2) at those radii for nonintensifying hurricanes. Differences in tangential wind structure (and I2) between the groups also imply differences in secondary circulation. The IN radial inflow layer is of nearly equal or greater thickness than nonintensifying groups, and all groups show an inflow maximum just outside the RMW. Nonintensifying hurricanes have stronger inflow outside the eyewall region, likely associated with frictionally forced ascent out of the BL and enhanced subsidence into the BL at radii outside the RMW. Equivalent potential temperatures (θe) and conditional stability are highest inside the RMW of nonintensifying storms, which is potentially related to TC intensity. At greater radii, inflow layer θe is lowest in WE hurricanes, suggesting greater subsidence or more convective downdrafts at those radii compared to IN and SS hurricanes. Comparisons of prior observational and theoretical studies are highlighted, especially those relating BL structure to large-scale vortex structure, convection, and intensity.

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12

RODRGUEZ-TOVAR, FRANCISCO J. y ALFRED UCHMAN. "Trace fossils after the KT boundary event from the Agost section, SE Spain". Geological Magazine 141, n.º 4 (julio de 2004): 429–40. http://dx.doi.org/10.1017/s0016756804009410.

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13

Chandrasekar, Thivya, Chidambaram Sabarathinam, Devaraj Nadesan, Thilagavathi Rajendiran, Banaja Rani Banajarani Panda, Tirumalesh Keesari, Prasanna Mohan Viswanathan, Vasudevan Utharapathi y Ramanathan Alagappan. "Geochemical (process based) characterization of groundwater along the KT boundary of South India". Geochemistry 79, n.º 1 (abril de 2019): 62–77. http://dx.doi.org/10.1016/j.geoch.2018.11.005.

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14

Premovic, Pavle, Nikola Nikolic, Mirjana Pavlovic y Katja Panov. "Geochemistry of the cretaceous-tertiary transition boundary at Blake Nose (N. W. Atlantic): Cosmogenic Ni". Journal of the Serbian Chemical Society 69, n.º 3 (2004): 205–23. http://dx.doi.org/10.2298/jsc0403205p.

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The Cretaceous-Tertiary (KT) boundary transition at the Blake Nose Plateau recovered by ODP Leg 171B (site 1049, hole A, core 17X, section 2) contains an ejecta bed (thickness ca. 17 cm) marking a late Cretaceous asteroid impact. The nature and geochemical composition of this bed imply that it originated mainly from the target rocks of the Chicxulub impact site (Yucatan Peninsula, Mexico), the site of the presumed asteroid impact. The ejecta bed of hole 1049A contains relatively high concentrations of Ni (up to 165 ppm) within the carbonate fraction. It is reasoned that this enhancement represents a sudden and rapid air fall of high cosmogenic Ni into he Blake Nose Basin. The source of the metal was the Chicxulub impacting (carbonaceous) chondrite. It is suggested that many calcareous planktons in the KT ocean surface water of the Blake Nose Plateau were probably vulnerable to the high influx of superacid rainfall and associated toxic metals (e.g. Ni) created by the impact.

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15

Gardner, A. D., C. C. Wolf, J. T. Heineck, M. Barnett y M. Raffel. "Helicopter Rotor Boundary Layer Transition Measurement in Forward Flight Using an Infrared Camera". Journal of the American Helicopter Society 65, n.º 1 (1 de enero de 2020): 2–14. http://dx.doi.org/10.4050/jahs.65.012002.

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Boundary layer transition measurement was demonstrated using differential infrared thermography (DIT) on the top side of a helicopter rotor in forward flight, which detects the difference in the convective heat transfer at the boundary layer transition position. The tests used a FLIR X8500xc SLS long wave infrared camera to observe the DLR EC135 test helicopter rotor. The boundary layer transition was detected for hover out of ground effect (150 ft) and for forward flight at 80 kt (1700 ft). The measured boundary layer transition positions are consistent with previous measurements of the EC135 hovering in ground effect, and with predicted boundary layer transition positions. A method for the analysis of DIT images for a rotor in forward flight is shown, based on computational analysis of a pitching airfoil with varying inflow.

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16

Maden, C., M. Döbeli, B. Hofmann y M. Suter. "In-situ Ir concentration measurements in KT-boundary sediments by accelerator secondary ion mass spectrometry". Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 219-220 (junio de 2004): 176–80. http://dx.doi.org/10.1016/j.nimb.2004.01.049.

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17

Wang, Chun Huy. "Microstructure and Characteristics of Pb(Ti,Zr)O₃ Ceramics with Addition of Pb-Based Glass Frit". Key Engineering Materials 280-283 (febrero de 2007): 189–94. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.189.

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The paper tries to prepare dense piezoceramics by way of reactive liquid phase sintering. Technique concerning a low-temperature sinterable process is developed by incorporating 4PbO×B2O3. The host system is a perovskite type piezoceramic, Pb(Ti,Zr)O3. If small amounts of 4PbO.B2O3 glass powder are added to the calcined Pb(Ti,Zr)O3 ceramics, the liquid phase is formed during sintering. Hence, the piezoelectric and dielectric properties are enhanced and the sintering temperature can be reduced. The value of the kp, KT 33 and Qm is increased and dielectric loss tangent is decreased when a small amounts of 4PbO.B2O3 dopant (i.e. 0.2 wt%) are added to the PZT system. With more 4PbO.B2O3 doping (i.e. 2 wt%), the value of the kp and KT 33 is decreased due to the glassy phase segregation at the grain boundary.

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18

Wasa, Kiyotaka, Isaku Kanno y Takaaki Suzuki. "Structure and Electromechanical Properties of Quenched PMN-PT Single Crystal Thin Films". Advances in Science and Technology 45 (octubre de 2006): 1212–17. http://dx.doi.org/10.4028/www.scientific.net/ast.45.1212.

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Thin films of single c-domain/single crystal (1-x)Pb(Mg1/3Nb2/3)O3－xPbTiO3 (PMN-PT), x≅0.33 near a morphotropic boundary (MPB) composition, were heteroepitaxially grown on (110)SRO/(001)Pt/(001)MgO substrates by magnetron sputtering. The heteroepitaxial growth was achieved by rf-magneron sputtering at the substrate temperature of 600oC. After sputtering deposition, the sputtered films were quenched from 600oC to room temperature in atmospheric air. The quenching enhanced the heteroepitaxial growth of the stress reduced single c-domain/single crystal PMN-PT thin films. Their electromechanical coupling factor kt measured by a resonance spectrum method was 45% at resonant frequency of 1.3GHz with phase velocity of 5500 to 6000m/s for the film thickness of 2.3μm. The d33 and d31 were 194pC/N and –104pC/N, respectively. The observed kt , d33 ,and d31were almost the same to the bulk single crystal values.

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19

Yin, Na, Abolfazl Jalalian, Zhi Gang Gai, Lan Ling Zhao y Xiao Lin Wang. "Effect of Doping Ions on Structure and Electrical Properties of Lead-Free KNN Ceramics". Advanced Materials Research 1058 (noviembre de 2014): 190–95. http://dx.doi.org/10.4028/www.scientific.net/amr.1058.190.

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Doping effect on the lattice parameters, vibration modes, dielectric and piezoelectric properties of LiSbO3, LiTaO3 and LiNbO3 substituted lead-free K0.5Na0.5NbO3 (KNN) ceramics are investigated. All compositions are crystallized in morphotropic phase boundary region. Enhanced piezoelectric and electromechanical response d33 ~176–197 pC/N, kp ~45%–48%, and kt~34%–47% obtained in the doped ceramics are due to the presence of the polymorphic phase transition between orthorhombic and tetragonal phase at room temperature.

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20

Luther, Andreas, Ralph Kleinschek, Leon Scheidweiler, Sara Defratyka, Mila Stanisavljevic, Andreas Forstmaier, Alexandru Dandocsi et al. "Quantifying CH<sub>4</sub> emissions from hard coal mines using mobile sun-viewing Fourier transform spectrometry". Atmospheric Measurement Techniques 12, n.º 10 (1 de octubre de 2019): 5217–30. http://dx.doi.org/10.5194/amt-12-5217-2019.

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Abstract. Methane (CH4) emissions from coal production amount to roughly one-third of European anthropogenic CH4 emissions in the atmosphere. Poland is the largest hard coal producer in the European Union with the Polish side of the Upper Silesian Coal Basin (USCB) as the main part of it. Emission estimates for CH4 from the USCB for individual coal mine ventilation shafts range between 0.03 and 20 kt a−1, amounting to a basin total of roughly 440 kt a−1 according to the European Pollutant Release and Transfer Register (E-PRTR, http://prtr.ec.europa.eu/, 2014). We mounted a ground-based, portable, sun-viewing FTS (Fourier transform spectrometer) on a truck for sampling coal mine ventilation plumes by driving cross-sectional stop-and-go patterns at 1 to 3 km from the exhaust shafts. Several of these transects allowed for estimation of CH4 emissions based on the observed enhancements of the column-averaged dry-air mole fractions of methane (XCH4) using a mass balance approach. Our resulting emission estimates range from 6±1 kt a−1 for a single shaft up to 109±33 kt a−1 for a subregion of the USCB, which is in broad agreement with the E-PRTR reports. Three wind lidars were deployed in the larger USCB region providing ancillary information about spatial and temporal variability of wind and turbulence in the atmospheric boundary layer. Sensitivity studies show that, despite drawing from the three wind lidars, the uncertainty of the local wind dominates the uncertainty of the emission estimates, by far exceeding errors related to the XCH4 measurements themselves. Wind-related relative errors on the emission estimates typically amount to 20 %.

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21

Chen, Buo-Fu, Christopher A. Davis y Ying-Hwa Kuo. "An Idealized Numerical Study of Shear-Relative Low-Level Mean Flow on Tropical Cyclone Intensity and Size". Journal of the Atmospheric Sciences 76, n.º 8 (12 de julio de 2019): 2309–34. http://dx.doi.org/10.1175/jas-d-18-0315.1.

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Abstract Given comparable background vertical wind shear (VWS) magnitudes, the initially imposed shear-relative low-level mean flow (LMF) is hypothesized to modify the structure and convective features of a tropical cyclone (TC). This study uses idealized Weather Research and Forecasting Model simulations to examine TC structure and convection affected by various LMFs directed toward eight shear-relative orientations. The simulated TC affected by an initially imposed LMF directed toward downshear left yields an anomalously high intensification rate, while an upshear-right LMF yields a relatively high expansion rate. These two shear-relative LMF orientations affect the asymmetry of both surface fluxes and frictional inflow in the boundary layer and thus modify the TC convection. During the early development stage, the initially imposed downshear-left LMF promotes inner-core convection because of high boundary layer moisture fluxes into the inner core and is thus favorable for TC intensification because of large radial fluxes of azimuthal mean vorticity near the radius of maximum wind in the boundary layer. However, TCs affected by various LMFs may modify the near-TC VWS differently, making the intensity evolution afterward more complicated. The TC with a fast-established eyewall in response to the downshear-left LMF further reduces the near-TC VWS, maintaining a relatively high intensification rate. For the upshear-right LMF that leads to active and sustained rainbands in the downshear quadrants, TC size expansion is promoted by a positive radial flux of eddy vorticity near the radius of 34-kt wind (1 kt ≈ 0.51 m s−1) because the vorticity associated with the rainbands is in phase with the storm-motion-relative inflow.

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22

YUKALOV, V. I. "SINGLE-PARTICLE EXCITATIONS IN SUPERFLUID HELIUM". Modern Physics Letters B 05, n.º 10 (30 de abril de 1991): 725–32. http://dx.doi.org/10.1142/s0217984991000897.

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We show theoretically that the collective spectrum of a Bose liquid contains, besides the well-known phonon-roton branch, single-particle excitations existing below the roton-stability boundary k r , but above a threshold kt. The existence of these single-particle excitations is not an experimental artifact as has been supposed earlier. Calculations made for superfluid helium give the threshold momentum k t ≅1 Å−1. This value and the attenuation found of the single-particle excitations are in very good agreement with experimental data.

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23

Thivya, C., S. Chidambaram, R. Thilagavathi, Venkatraman, N. Ganesh, Banajarani Panda y M. V. Prasanna. "Short-term Periodic Observation of the Relationship of Climate Variables to Groundwater Quality along the KT Boundary". Journal of Climate Change 4, n.º 2 (6 de agosto de 2018): 77–86. http://dx.doi.org/10.3233/jcc-1800015.

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24

Wang, Yuxuan, Yuanyu Xie, Libao Cai, Wenhao Dong, Qianqian Zhang y Lin Zhang. "Impact of the 2011 Southern U.S. Drought on Ground-Level Fine Aerosol Concentration in Summertime*". Journal of the Atmospheric Sciences 72, n.º 3 (24 de febrero de 2015): 1075–93. http://dx.doi.org/10.1175/jas-d-14-0197.1.

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Abstract This study investigates the impacts of the 2011 severe drought in the southern United States on ground-level fine aerosol (PM2.5) concentrations in the summer. The changes in surface concentrations and planetary boundary layer (PBL) budget of PM2.5 between June 2010 (near-normal rainfall) and June 2011 (severe drought) are quantified using surface observations and the GEOS-Chem model. Observations show an average enhancement of 26% (p < 10−4) in total PM2.5 over the southern U.S. (SUS) region during the drought, which is largely attributed to a ~120% increase in organic carbon (OC). Over Texas (TX) under extreme drought conditions, surface PM2.5 shows a mean decrease of 10.7% (p < 0.15), which is mainly driven by a decrease of 26% (p < 0.03) in sulfate. Model simulations reproduce the observed relative changes in total PM2.5, OC, and sulfate during the drought. The model correctly identifies OC as the major contributor to the overall PM2.5 increase over SUS and sulfate as the key driver of the PM2.5 decrease over TX. Budget analysis suggests that increased OC emissions from wildfires (+58 kt C month−1), enhanced SOA production (+1.1 kt C month−1), and transboundary inflow from Mexico (+8.6 kt C month−1) are major contributors to the increase in atmospheric OC contents over SUS. Over TX, a 70% decrease of aqueous-phase oxidation of sulfate, driven by decreasing low clouds, outweighs the combined effects of reduced wet deposition and decreased outflow as the key driver of sulfate decrease both at the surface and within the PBL.

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25

Devaraj, N., S. Chidambaram, Banajarani Panda, C. Thivya, R. Thilagavathi y N. Ganesh. "Geo-electrical approach to determine the lithological contact and groundwater quality along the KT boundary of Tamilnadu, India". Modeling Earth Systems and Environment 4, n.º 1 (13 de febrero de 2018): 269–79. http://dx.doi.org/10.1007/s40808-018-0424-2.

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26

Wang, Chun Huy. "Physical and Electrical Properties of Lead-Free (Bi_0.5Na_0.5)TiO₃–(Bi_0.5K_0.5)TiO₃ Ceramics". Advanced Materials Research 239-242 (mayo de 2011): 3240–43. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.3240.

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Extending the investigations on (Bi0.5Na0.5)TiO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Bi0.5Na0.5)TiO3–(Bi0.5K0.5)TiO3[BNT-BKT]. (Bi0.5Na0.5)TiO3with 7~ 30 mol% (Bi0.5K0.5)TiO3ceramics have been prepared following the conventional mixed oxide process. A morphotropic phase boundary (MPB) between rhombohedral (R) and tetragonal (T) was found at the composition 0.82BNT-0.18BKT with correspondingly enhanced piezoelectric properties. The electromechanical planar coupling factor is higher for compositions near the MPB. The mechanical quality factor (Qm), planar coupling coefficient (kp) and thickness coupling coefficient (kt) of 0.82BNT-0.18BKT ceramics were 125, 28.8% and 47.4%, respectively.

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27

Guagliano, M., A. Terranova y L. Vergani. "Theoretical and Experimental Study of the Stress Concentration Factor in Diesel Engine Crankshafts". Journal of Mechanical Design 115, n.º 1 (1 de marzo de 1993): 47–52. http://dx.doi.org/10.1115/1.2919323.

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The paper deals with the bending stress concentration evaluation of a marine diesel engine crankshaft. Experimental strain gauge tests were conducted on a full scale single crank to measure the stress concentration near the crank fillet. A three-dimensional finite element schematization of the crankshaft and the linear elastic calculations conducted show the stress field along the most overstressed zone and how it is influenced by different load conditions. It is now possible to calculate accurately the stress concentration factor Kt. However, a mesh of a mechanical element with a complex geometry like crankshaft is very expensive and difficult. Therefore a bidimensional model of the crankshaft has been also considered: experimental tests and numerical analyses under different load conditions were also carried out in this case. The agreement between the results obtained from these different kinds of analyses is good. The values of the stress concentration factors obtained from bidimensional and three-dimensional analysis with the same boundary and load conditions are similar. A plane model of crankshaft can be utilized to determine the theoretical stress concentration factor Kt with considerable saving of calculation time.

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28

Van Dijk, Claudia M. A., Steven G. Ledesma y Isaac Teitelbaum. "Patient Characteristics Associated with Defects of the Peritoneal Cavity Boundary". Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 25, n.º 4 (julio de 2005): 367–73. http://dx.doi.org/10.1177/089686080502500412.

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Background Conflicting literature exist regarding the patient characteristics that may confer an increased risk for anatomic complications of the peritoneal cavity boundaries. Methods We collected data from 75 randomly selected units in the United States and Canada, representing a total of 1864 peritoneal dialysis (PD) patients. Results 200 of these patients experienced a total of 217 anatomic complications between July 2000 and June 2001; 16 patients had more than 1 complication. Hernias comprised 60.4% of all complications: 24.9% inguinal, 18.9% umbilical, 13.8% ventral, 2.3% femoral, and 0.5% intrathoracic. Other complications included pericatheter or subcutaneous leak (25.3%), hydrothorax (6.0%), and miscellaneous (8.3%). Peritoneal dialysis modalities in use at the time of complication were automated PD (52.3%), continuous ambulatory PD (38.6%), and nocturnal intermittent PD (9.1%). The overall incidence of hernias was 7%. Conclusions Logistic regression analysis found no association between hernias and age, body surface area, PD modality, volume of dialysate, time of largest dwell (day/upright vs night/recumbent), or type of catheter used. Cystic disease conferred a 2.5-fold increase in risk for anatomic complications ( p < 0.001); female gender conferred an 80% reduction in risk ( p < 0.0001), and Kt/V ≥2.0 conferred a 52% reduction in risk ( p < 0.05) for hernia.

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29

Krautwurst, Sven, Konstantin Gerilowski, Haflidi H. Jonsson, David R. Thompson, Richard W. Kolyer, Laura T. Iraci, Andrew K. Thorpe et al. "Methane emissions from a Californian landfill, determined from airborne remote sensing and in situ measurements". Atmospheric Measurement Techniques 10, n.º 9 (20 de septiembre de 2017): 3429–52. http://dx.doi.org/10.5194/amt-10-3429-2017.

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Abstract. Fugitive emissions from waste disposal sites are important anthropogenic sources of the greenhouse gas methane (CH4). As a result of the growing world population and the recognition of the need to control greenhouse gas emissions, this anthropogenic source of CH4 has received much recent attention. However, the accurate assessment of the CH4 emissions from landfills by modeling and existing measurement techniques is challenging. This is because of inaccurate knowledge of the model parameters and the extent of and limited accessibility to landfill sites. This results in a large uncertainty in our knowledge of the emissions of CH4 from landfills and waste management. In this study, we present results derived from data collected during the research campaign COMEX (CO2 and MEthane eXperiment) in late summer 2014 in the Los Angeles (LA) Basin. One objective of COMEX, which comprised aircraft observations of methane by the remote sensing Methane Airborne MAPper (MAMAP) instrument and a Picarro greenhouse gas in situ analyzer, was the quantitative investigation of CH4 emissions. Enhanced CH4 concentrations or CH4 plumes were detected downwind of landfills by remote sensing aircraft surveys. Subsequent to each remote sensing survey, the detected plume was sampled within the atmospheric boundary layer by in situ measurements of atmospheric parameters such as wind information and dry gas mixing ratios of CH4 and carbon dioxide (CO2) from the same aircraft. This was undertaken to facilitate the independent estimation of the surface fluxes for the validation of the remote sensing estimates. During the COMEX campaign, four landfills in the LA Basin were surveyed. One landfill repeatedly showed a clear emission plume. This landfill, the Olinda Alpha Landfill, was investigated on 4 days during the last week of August and first days of September 2014. Emissions were estimated for all days using a mass balance approach. The derived emissions vary between 11.6 and 17.8 kt CH4 yr−1 with related uncertainties in the range of 14 to 45 %. The comparison of the remote sensing and in situ based CH4 emission rate estimates reveals good agreement within the error bars with an average of the absolute differences of around 2.4 kt CH4 yr−1 (±2. 8 kt CH4 yr−1). The US Environmental Protection Agency (EPA) reported inventory value is 11.5 kt CH4 yr−1 for 2014, on average 2.8 kt CH4 yr−1 (±1. 6 kt CH4 yr−1) lower than our estimates acquired in the afternoon in late summer 2014. This difference may in part be explained by a possible leak located on the southwestern slope of the landfill, which we identified in the observations of the Airborne Visible/Infrared Imaging Spectrometer – Next Generation (AVIRIS-NG) instrument, flown contemporaneously aboard a second aircraft on 1 day.

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Mauri, Ezio L. y William A. Gallus Jr. "Differences between Severe and Nonsevere Warm-Season, Nocturnal Bow Echo Environments". Weather and Forecasting 36, n.º 1 (febrero de 2021): 53–74. http://dx.doi.org/10.1175/waf-d-20-0137.1.

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AbstractNocturnal bow echoes can produce wind damage, even in situations where elevated convection occurs. Accurate forecasts of wind potential tend to be more challenging for operational forecasters than for daytime bows because of incomplete understanding of how elevated convection interacts with the stable boundary layer. The present study compares the differences in warm-season, nocturnal bow echo environments in which high intensity [>70 kt (1 kt ≈ 0.51 m s−1)] severe winds (HS), low intensity (50–55 kt) severe winds (LS), and nonsevere winds (NS) occurred. Using a sample of 132 events from 2010 to 2018, 43 forecast parameters from the SPC mesoanalysis system were examined over a 120 km × 120 km region centered on the strongest storm report or most pronounced bowing convective segment. Severe composite parameters are found to be among the best discriminators between all severity types, especially derecho composite parameter (DCP) and significant tornado parameter (STP). Shear parameters are significant discriminators only between severe and nonsevere cases, while convective available potential energy (CAPE) parameters are significant discriminators only between HS and LS/NS bow echoes. Convective inhibition (CIN) is among the worst discriminators for all severity types. The parameters providing the most predictive skill for HS bow echoes are STP and most unstable CAPE, and for LS bow echoes these are the V wind component at best CAPE (VMXP) level, STP, and the supercell composite parameter. Combinations of two parameters are shown to improve forecasting skill further, with the combination of surface-based CAPE and 0–6-km U shear component, and DCP and VMXP, providing the most skillful HS and LS forecasts, respectively.

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31

Wang, Chun Huy. "Dielectric and Piezoelectric Properties of Lead-Free (Na_0.5K_0.5)NbO₃- Bi_0.5(Na_0.85K_0.15)_0.5TiO₃ Ceramics". Advanced Materials Research 211-212 (febrero de 2011): 152–55. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.152.

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Extending the investigations on (Na0.5K0.5)NbO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Na0.5K0.5)NbO3–Bi0.5(Na0.85K0.15)0.5TiO3[NKN-BNKT]. (Na0.5K0.5)NbO3with 2 ~ 6 mol% Bi0.5(Na0.85K0.15)0.5TiO3has been prepared following the conventional mixed oxide process. A morphotropic phase boundary (MPB) between orthorhombic (O) and hexagonal (H) was found at the composition 0.96NKN-0.04BNKT with correspondingly enhanced dielectric and piezoelectric properties. The electromechanical coupling factor and dielectric constant are higher for compositions near the MPB. The dielectric constant (KT33), planar coupling coefficient (kp) and thickness coupling coefficient (kt)of 0.96NKN-0.04BNKT ceramics were 1273, 34% and 38%, respectively.

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32

Wang, Chun Huy. "Piezoelectric and Electrical Properties of Lead-Free (Na_0.5K_0.5)NbO₃- Bi_0.5(Na_0.80K_0.20)_0.5TiO₃ Ceramics". Advanced Materials Research 230-232 (mayo de 2011): 12–15. http://dx.doi.org/10.4028/www.scientific.net/amr.230-232.12.

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Extending the investigations on (Na0.5K0.5)NbO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Na0.5K0.5)NbO3–Bi0.5(Na0.80K0.20)0.5TiO3[NKN-BNKT]. (Na0.5K0.5)NbO3with 2 ~ 6 mol% Bi0.5(Na0.80K0.20)0.5TiO3has been prepared following the conventional mixed oxide process. A morphotropic phase boundary (MPB) between orthorhombic (O) and tetragonal (T) was found at the composition 0.97NKN-0.03BNKT with correspondingly enhanced dielectric and piezoelectric properties. The electromechanical coupling factor and dielectric constant are higher for compositions near the MPB. The dielectric constant (εr), planar coupling coefficient (kp) and thickness coupling coefficient (kt)of 0.97NKN-0.03BNKT ceramics were 1483, 32% and 31%, respectively.

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33

Wang, Chun Huy. "Electrical and Physical Properties of Lead-Free (Na_0.5K_0.5)NbO₃- Bi_0.5(Na_0.₉₃K_0.₀₇)_0.5TiO₃ Ceramics". Key Engineering Materials 512-515 (junio de 2012): 1351–54. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.1351.

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Extending the investigations on (Na0.5K0.5)NbO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Na0.5K0.5)NbO3–Bi0.5(Na0.93K0.07)0.5TiO3 [NKN-BNKT]. (Na0.5K0.5)NbO3 with 2 ~ 6 mol% Bi0.5(Na0.93K0.07)0.5TiO3 has been prepared following the conventional mixed oxide process. A morphotropic phase boundary (MPB) between orthorhombic (O) and rhombohedral (R) was found at the composition 0.98NKN-0.02BNKT with correspondingly enhanced dielectric and piezoelectric properties. The electromechanical coupling factor and dielectric constant are higher for compositions near the MPB. The dielectric constant (KT33), planar coupling coefficient (kp) and thickness coupling coefficient (kt)of 0.98NKN-0.02BNKT ceramics were 1040, 47% and 48%, respectively.

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34

Guénault, A. M. y G. R. Pickett. "Properties of superfluid 3He–B in the low-temperature limit". Canadian Journal of Physics 65, n.º 11 (1 de noviembre de 1987): 1494–96. http://dx.doi.org/10.1139/p87-236.

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Several experiments are described in 3He–B at temperatures down to 125 μK and below. In this low-temperature regime, the normal-fluid density is negligible with the consequence that the quasi-particle gas is virtually noninteracting, because the mean free paths for quasi-particle–quasi–particle scattering are orders of magnitude greater than the size of the experiment. We have measured the boundary conductance across a liquid-to-silver sinter interface. The measured conductance shows an exp(−Δ/kT) dependence, with Δ being a superfluid energy gap that is apparently lower than that appropriate for the bulk liquid. We observe the onset of dissipation by pair-breaking induced by a moving wire, which also implies that the energy gap is depressed near a boundary. Finally, we have used such a supercritically driven wire as a ballistic quasi-particle source to observe a new thermomechanical effect in 3He–B, and hence to devise the elements of a quasi-particle spectrometer.

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35

Scarbrough, Harry, Daniela D’Andreta, Sarah Evans, Marco Marabelli, Sue Newell, John Powell y Jacky Swan. "Networked innovation in the health sector: comparative qualitative study of the role of Collaborations for Leadership in Applied Health Research and Care in translating research into practice". Health Services and Delivery Research 2, n.º 13 (mayo de 2014): 1–128. http://dx.doi.org/10.3310/hsdr02130.

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BackgroundCollaborations for Leadership in Applied Health Research and Care (CLAHRCs) were an initiative of the National Institute for Health Research in response to a new research and development strategy in the NHS: ‘Best Research for Best Health’. They were designed to address the ‘second gap in translation’ identified by the Cooksey review; namely, the need to improve health care in the UK by translating clinical research into practice more effectively. Nine CLAHRCs, each encompassing a university in partnership with local NHS bodies, were funded over the period 2008–13.AimsThe aim of this report is to provide an independent and theory-based evaluation of CLAHRCs as a new form of networked innovation in the health sector. This evaluation is based on an intensive research study involving three CLAHRCs in the UK and three international organisations (one in the USA and two in Canada). This study was carried out over two overlapping time phases so as to capture changes in the CLAHRCs over time. Networked innovation in the health sector is conceptualised as involving the translation of knowledge via informal social networks.MethodsA mix of research methods was used to help ensure the validity and generalisability of the study. These methods addressed the development of each CLAHRC over time, over multiple levels of analysis, and with particular reference to the translation of knowledge across the groups involved, and the quality of the informal underpinning network ties that supported such translation. Research methods, therefore, included a qualitative enquiry based on case studies and case analysis, cognitive mapping methods, and social network analysis.FindingsThrough our study, we found that each one of our samples of CLAHRCs appropriated the CLAHRC idea in a particular way, depending on their different interpretations or ‘visions’ of the CLAHRC’s role in knowledge translation (KT), and different operating models of how such visions could be achieved. These helped to shape the development of social networks (centralised vs. decentralised) and each CLAHRC’s approach to KT activity (‘bridging’ vs. ‘blurring’ the boundaries between professional groups). Through a comparative analysis, we develop an analytical model of the resultant capabilities which each case, including our international sites, developed for undertaking innovation, encompassing a combination of both ‘integrative capability’ (the ability to move back and forth between scientific evidence and practical application) and ‘relational capability’ (the ability of groups and organisations to work together). This extends previous models of KT by highlighting the effects of leadership and management, and the emergence of social network structures. We further highlight the implications of this analysis for policy and practice by discussing how network structures and boundary-spanning roles and activities can be tailored to different KT objectives.ConclusionsDifferent interpretations and enactments of the CLAHRC mission ultimately led to differing capabilities for KT among our studied initiatives. Further research could usefully explore how these different capabilities are produced, and how they may be more or less appropriate for particular national health-care settings, with a view to improving the design blueprint for future KT initiatives.FundingThe National Institute for Health Research Health Services and Delivery Research programme.

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KOZLENKO, M. y Yu KOZLENKO. "The structure of the lithosphere, tectonics and evolution of the Scythian Plate and adjacent structures in the section of the Bs05-22 profile (according to 2-d density modeling)". Geology and Mineral Resources of World Ocean 16, n.º 3 (2020): 13–29. http://dx.doi.org/10.15407/gpimo2020.03.013.

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A density model was built along the Bs05-22 profile, which made it possible to identify individual blocks with different crustal parameters. The consolidated crust of the East European Platform (EEP) has a “key” structure. The southern boundary of the EEP is clearly fractured and falls to the south at an angle of about 83° The South Ukrainian monocline (SUM) covers not only the basement of the EEP but also the northern part of the Scythian Plate (SP). The central part of SP block overlapped by the SUM is characterized by the maximum capacity of the folded-metamorphic base. The axial part of the Karkinit Trough (KT) has a structure typical for riftogens. The rift is practically one-sided with a width of 6.5 km. The southern slope of the KT developed as a result of the falling of the surface by the mechanism of the planj-principle. The border between the Karkinit Trough and the Kalamitsky rise (KR) is clearly defined by the Sulinsko-Tarkhankutsk fault. The core of the KR is a sufficiently massive body of lenticular shape with a density corresponding to the Taurian series of the Mountainous Crimea. There is a narrow transition zone between KT and Edge step (ES). The southern edge of the Scythian plate is a 25,0 km wide transition zone to West-Black Sea depression (WBSD). Modeling established the extension of the “granodiorite” layer into the WBSD for 100 km. The crust thickness within the EEP is 44,0 km, on the Scythian plate under SUM is average 43.5 km, 37,0 km within KT and 33,0 km under ES, in the West Black Sea basin 28,7 km under the foot of the Upper Cretaceous continental slope and 21,5 km at the southern edge of the profile. In the model chosen, the density of tectonic faults in the EEP is 0,06 and in the SP — 0,14 per 1,0 km. Vertical shifts of crystalline crust blocks at SP reach 5,5 km, which is almost three times higher than at the southern flank of the EEP. The most of disjunctions are vertical and have transcrust stretch. The structure of the Earth’s crust obtained as a result of modeling allowed us to draw some conclusions about the Meso-Cenozoic evolution of the studied region in the profile section. At the southern edge of the EEP in the Late Cimmerian tectogenesis epoch there has been a revitalization, in the Alpine phase this structure was generally passive. Activity of the Cimmerian epoch was observed throughout the Scythian plate: within the Kalmitsky rise from the early phase, and in the Karkinit Trough and on the Edge step from the late Cimmerian phase. The periods of activation on the KT and KR are traced up to the Sawa phase, and on the ES — to the Walach phase of the Alpine tectogenesis inclusive.

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Premovic, Pavle, Milena Krsmanovic, Bratislav Todorovic, Mirjana Pavlovic, Nikola Nikolic y Dragan Djordjevic. "Geochemistry of the cretaceous-tertiary boundary (Fish Clay) at Stevns Klint (Denmark): Ir, Ni and Zn in kerogen". Journal of the Serbian Chemical Society 71, n.º 7 (2006): 793–806. http://dx.doi.org/10.2298/jsc0607793p.

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Geochemical analyses of trace metals (Ir, Ni and Zn) in the kerogen of the black marl of the Cretaceous-Tertiary boundary succession (Fish Clay) at Stevns Klint (H?jerup Church) were undertaken. The data for this kerogen were in accordance with a previous hypothesis that this (insoluble) geoorganic polymer was derived from humic substances (mainly humic acids) of a nearshore soil. Substantial proportions of Ir, Ni and Zn within the kerogen structure were probably contained in these substances arriving at the sedimentary site. It is proposed that these humics were probably transported by acid surface waters (induced by the KT asteroid impact) into the shallow marine basin of Stevns Klint. It is also suggested that local leaching/weathering of the asteroidal impact fallout on the land near these waters played an important role in providing Ir, Ni and Zn for these substances. Apparently, Ir, Ni and Zn of the kerogen were created by the chondritic component of the impact ejecta fallout.

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Koch, Karsten A. "Some properties of prosodic phrasing in Thompson Salish". ZAS Papers in Linguistics 52 (1 de enero de 2010): 141–58. http://dx.doi.org/10.21248/zaspil.52.2010.386.

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In Nłeʔkepmxcin, consonant-heavy inventories, lengthy obstruent clusters and widespread glottalization can make potential F0 cues to prosodic phrase boundaries (e.g. boundary tones or declination reset) difficult to observe phonetically. In this paper, I explore a test that exploits one behaviour of phrasefinal consonant clusters to test for prosodic phrasing in Nłeʔkepmxcin clauses. Final /t/ of the 1pl marker kt is aspirated when phrase-final, but not phraseinternally. Use of this test suggests that Thompson Salish speakers parse verbs, arguments and adjuncts into separate phonological phrases. However, complex verbal predicates and complex noun phrases are parsed as single phonological phrases. Implications are discussed, especially in regards to findings that (absence of) pitch accent is not employed to signal the informational categories of Focus and Givenness, even though Nłeʔkepmxcin is a stress language.

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Wang, Chun Huy. "Electrical and Physical Properties of Lead-Free (Na_0.5K_0.5)NbO₃- Bi_0.5(Na_0.90K_0.10)_0.5TiO₃ Ceramics". Key Engineering Materials 602-603 (marzo de 2014): 791–94. http://dx.doi.org/10.4028/www.scientific.net/kem.602-603.791.

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Extending the investigations on (Na0.5K0.5)NbO3-based solid solution for lead-free piezoelectric ceramics, this paper consider the complex solid-solution system (Na0.5K0.5)NbO3Bi0.5(Na0.90K0.10)0.5TiO3 [NKN-BNK. (Na0.5K0.5)NbO3 with 1 ~ 5 mol% Bi0.5(Na0.90K0.10)0.5TiO3 has been prepared following the conventional mixed oxide process. It can be concluded that the NKN-BNKT ceramics have orthorhombic structures in the case x 0.03. With increasing BNKT content (x=0.04 to 0.05), however, the structure changes from orthorhombic to rhombohedral phase. Above results demonstrated that the MPB between orthorhombic and rhombohedral phases exits in the solid solution with the BNKT content of x=0.03. At the MPB composition, the cryctalline structure of ceramics is considered to be a coexistence of orthorhombic and rhombohedral phase. Owing to the phase coexistence at the phase boundary, there exists a different symmetry regions (DSR) near the MPB. The DSR boundary motion increases the dielectric permittivity and piezoelectric coefficients. The electromechanical coupling factor and dielectric constant are higher for compositions near the MPB. The dielectric constant (KT33), planar coupling coefficient (kp), thickness coupling coefficient (kt) and piezoelectric constant (d33)of 0.98NKN-0.02BNKT ceramics were 1180, 30%, 58%, and 180, respectively.

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40

Wang, Chun Huy y Ming Qiu Wei. "Microstructure and Electrical Properties of Lead-Free (Na_0.5K_0.5)NbO₃ - Bi_0.5(Na_0.97K_0.03)_0.5TiO₃ Ceramics". Applied Mechanics and Materials 368-370 (agosto de 2013): 760–63. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.760.

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(Na0.5K0.5)NbO3 with Bi0.5(Na0.97K0.03)0.5TiO3 with x≤0.05 has been prepared by the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all the Bi(Na0.97K0.03)TiO3 diffuses into the lattice of (Na0.5K0.5)NbO3 to form a solid solution with a perovskite structure. A morphotropic phase boundary (MPB) between orthorhombic (O) and rhombohedral (R) was found at the composition 0.98(Na0.5K0.5)NbO3-0.02Bi0.5(Na0.97K0.03)0.5TiO3 [abbreviated as 0.98NKN-0.02BNKT] with correspondingly enhanced dielectric and piezoelectric properties. For 0.98NKN-0.02BNKT ceramics, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.33 and 0.49, respectively, after sintering at 1100 oC for 3 h. The ratio of the thickness coupling coefficient to the planar coupling coefficient is 1.48. With suitable Bi0.5(Na0.97K0.03)0.5TiO3 concentration, a dense microstructure and good electrical properties are obtained.

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OLDS, Peter y Norm SLEEP. "Regarding an Oceanic Crust/Upper Mantle Geochemical Signature at the KT Boundary: If not from Chicxulub Crater, then Where Did it Come from?" Acta Geologica Sinica - English Edition 91, s1 (mayo de 2017): 28–29. http://dx.doi.org/10.1111/1755-6724.13164.

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Pigg, Kathleen B. "BotanyPlants and the KT Boundary. By DouglasJ.Nichols and KirkR.Johnson. Cambridge and New York: Cambridge University Press. $130.00. x 280 p.; ill.; index. 9780521835756. 2008." Quarterly Review of Biology 84, n.º 3 (septiembre de 2009): 309. http://dx.doi.org/10.1086/644706.

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Buyanovskii, I. A., V. D. Samusenko y Y. I. Shcherbakov. "Modernization of friction unit of a KT-2 tribometer for evaluation of the friction properties of thin coatings upon friction in boundary lubrication conditions". Industrial laboratory. Diagnostics of materials 85, n.º 12 (29 de diciembre de 2019): 65–69. http://dx.doi.org/10.26896/1028-6861-2019-85-12-65-68.

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The results of studying the tribological characteristics of thin coatings of steel parts on a modernized friction unit of a KT-2 machine in the boundary lubrication mode are presented. To provide high accuracy and reproducibility of the results standard elements of rolling bearings — balls and rollers, which are characterized by the uniformity of the structure and composition, as well as high quality of the surface treatment are used as samples. The developed design of the mandrel ensured friction contact of the ball mounted on the machine spindle with the ends of three rollers mounted with high accuracy at an angle of 35°30’ to spindle axis of the installation to ensure the same distribution of the axial load between three rollers like in the case of the four-ball contact between three lower balls. The coatings under study were applied to the flat ends of the rollers, which is much easier than their application to cylindrical or spherical surfaces. A standard ball made of steel ShKh-15 or wear-resistant ceramics served as a counterbody. The modernized unit is recommended to be used on traditional four-ball machines for laboratory assessment of the effect of thin wear-resistant coatings on the antifriction properties of lubricants.

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Pettegrew, Brian P., Patrick S. Market, Raymond A. Wolf, Ronald L. Holle y Nicholas W. S. Demetriades. "A Case Study of Severe Winter Convection in the Midwest". Weather and Forecasting 24, n.º 1 (1 de febrero de 2009): 121–39. http://dx.doi.org/10.1175/2008waf2007103.1.

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Abstract Between 2100 UTC 11 February 2003 and 0200 UTC 12 February 2003, a line of thunderstorms passed swiftly through parts of eastern Iowa and into north-central Illinois. Although this storm somewhat resembled a warm season, line-type mesoscale convective system, it was unique in that the thunderstorm winds exceeded the severe criterion (50 kt; 25.7 m s−1) during a snowburst. While the parent snowband deposited only 4 cm of snow, it did so in a short period and created a treacherous driving situation because of the ensuing near-whiteout conditions caused by strong winds that reached the National Weather Service severe criteria, as the line moved across central Illinois. Such storms in the cold season rarely occur and are largely undocumented; the present work seeks to fill this void in the existing literature. While this system superficially resembled a more traditional warm season squall line, deeper inspection revealed a precipitation band that failed to conform to that paradigm. Radar analysis failed to resolve any of the necessary warm season signatures, as maximum reflectivities of only 40–45 dBZ reached no higher than 3.7 km above ground level. The result was low-topped convection in a highly sheared environment. Moreover, winds in excess of 50 kt (25.7 m s−1) occurred earlier in the day without thunderstorm activity, upstream of the eventual severe thundersnow location. Perhaps of greatest importance is the fact that the winds in excess of the severe criterion were more the result of boundary layer mixing, and largely coincident with the parent convective line. This event was a case of forced convection, dynamically linked to its parent cold front via persistent frontogenesis and the convective instability associated with it; winds sufficient for a severe thunderstorm warning, while influenced by convection, resulted from high momentum mixing downward through a dry-adiabatic layer.

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Shibagaki, Yoshiaki, Toyoshi Shimomai, Toshiaki Kozu, Shuichi Mori, Yasushi Fujiyoshi, Hiroyuki Hashiguchi, Masayuki K. Yamamoto, Shoichiro Fukao y Manabu D. Yamanaka. "Multiscale Aspects of Convective Systems Associated with an Intraseasonal Oscillation over the Indonesian Maritime Continent". Monthly Weather Review 134, n.º 6 (1 de junio de 2006): 1682–96. http://dx.doi.org/10.1175/mwr3152.1.

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Abstract Multiscale aspects of convective systems over the Indonesian Maritime Continent in the convectively active phase of an intraseasonal oscillation (ISO) during November 2002 are studied using Geostationary Meteorological Satellite infrared data and ground-based observational data from X-band rain radar, equatorial atmosphere radar, L-band boundary layer radar, and upper-air soundings at Koto Tabang (KT; 0.20°S, 100.32°E; 865 m above mean sea level), West Sumatera, Indonesia. In the analysis period, four super cloud clusters (SCCs; horizontal scale of 2000–4000 km), associated with an ISO, are seen to propagate eastward from the eastern Indian Ocean to the Indonesian Maritime Continent. The SCCs are recognized as envelopes of convection, composed of meso-α-scale cloud clusters (MαCCs; horizontal scale of 500–1000 km) propagating westward. When SCCs reach the Indonesian Maritime Continent, the envelopes disappear but MαCCs are clearly observed. Over Sumatera, the evolution and structure of a distinct MαCC is closely related to the organization of localized cloud systems with a diurnal cycle. The cloud systems are characterized by westward-propagating meso-β-scale cloud clusters (MβCCs; horizontal scale of ∼100 km) developed in eastern Sumatera, and an orographic cloud system formed over a mountain range in western Sumatera. Ground-based observations further revealed the internal structure of the orographic cloud system around KT. A meso-β-scale convective precipitation system with eastward propagation (E-MβCP; horizontal scale of ∼40 km) is found with the formation of the orographic cloud system. This is associated with a low-level wind change from easterly to westerly, considered to be local circulation over the mountain range. The E-MβCP also indicates a multicell structure composed of several meso-γ-scale convective precipitation systems (horizontal scale of <10 km) with multiple evolution stages (formation, development, and dissipation).

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Kralchevsky, P. A., V. N. Paunov y Kuniaki Nagayama. "Lateral capillary interaction between particles protruding from a spherical liquid layer". Journal of Fluid Mechanics 299 (25 de septiembre de 1995): 105–32. http://dx.doi.org/10.1017/s0022112095003442.

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The lateral capillary interaction between two particles immersed in a spherical thin liquid film is investigated. The interfacial shape, the lateral capillary force and the interparticle energy are calculated by using the numerical solution of the linearized Laplace equation of capillarity. Orthogonal bipolar coordinates on a sphere (inducing biconical coordinates in space) are introduced as a helpful instrument for solving this problem and other problems of similar geometry. We consider two types of boundary conditions at the particle surfaces: fixed contact angle and fixed contact line. We established that for particles of fixed contact angle the capillary interaction energy depends monotonically on the interparticle distance whereas for particles of fixed contact line the interaction energy exhibits a maximum. The numerical results show that in both cases the capillary interaction is much larger than the thermal energy kT and can induce aggregation and ordering of submicrometre particles. These theoretical findings can be important for understanding the properties of Pickering emulsions (stabilized by particles) and liposomes or biomembranes containing incorporated membrane proteins.

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Soundararajan, Raji, Rabindra Nath Das, Russ Tjossem, Amit Bandyopadhyay, Kelvin G. Lynn, Elgin E. Eisser y Jerry Lazaroff. "Growth and characterization of single-crystal lead magnesium niobate–lead titanate via high-pressure vertical Bridgman method". Journal of Materials Research 19, n.º 2 (febrero de 2004): 609–15. http://dx.doi.org/10.1557/jmr.2004.19.2.609.

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We have grown lead magnesium niobate–lead titanate (PMN–PT) single crystals, using the high-pressure vertical Bridgman (HPVB) technique, around the stoichiometric composition of 0.7 PMN–0.3PT [0.7Pb(Mg1/3Nb2/3)O3 + 0.3(PbTiO3)]. The final ingot (about 50-mm diameter, 25-mm long) was machinable using an inner diameter saw. The room-temperature x-ray diffraction on the starting powders and the final single crystal revealed a desirable perovskite structure. The natural growth direction in most of the crystals, as determined using orientation image microscopy, was (110). Examination of the final microstructures and phases/inclusions had been done using optical and infrared microscopy, energy dispersive spectroscopy, and x-ray backscatter techniques. Microstructural characterizations of the final ingots have revealed the presence of pores filled with Mg–Si–O-rich impurity phase, usually found along the cell boundary–like structures, in all the growths. We have measured some piezoelectric properties including d33 (1200 pC/N), k33 (0.85), kt (0.5), and the dielectric constant at the Curie temperature.

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48

Hendricks, Eric A., Melinda S. Peng, Xuyang Ge y Tim Li. "Performance of a Dynamic Initialization Scheme in the Coupled Ocean–Atmosphere Mesoscale Prediction System for Tropical Cyclones (COAMPS-TC)". Weather and Forecasting 26, n.º 5 (1 de octubre de 2011): 650–63. http://dx.doi.org/10.1175/waf-d-10-05051.1.

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Abstract A dynamic initialization scheme for tropical cyclone structure and intensity in numerical prediction systems is described and tested. The procedure involves the removal of the analyzed vortex and, then, insertion of a new vortex that is dynamically initialized to the observed surface pressure into the numerical model initial conditions. This new vortex has the potential to be more balanced, and to have a more realistic boundary layer structure than by adding synthetic data in the data assimilation procedure to initialize the tropical cyclone in a model. The dynamic initialization scheme was tested on multiple tropical cyclones during 2008 and 2009 in the North Atlantic and western North Pacific Ocean basins using the Naval Research Laboratory’s tropical cyclone version of the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS-TC). The use of this initialization procedure yielded significant improvements in intensity forecasts, with no degradation in track performance. Mean absolute errors in the maximum sustained surface wind were reduced by approximately 5 kt for all lead times up to 72 h.

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49

Tsai, Cheng Che, Hsiang Ho Hsieh, Sheng Yuan Chu, Zong You Chen y S. K. Huang. "Characterizations of (Mn, Sb) Co-Tuned PZMNS-PZT Piezoelectric Ceramics in the Morphotropic Phase Boundary and their Applications on Multi-Bulk Step-Down Piezoelectric Transformers". Key Engineering Materials 655 (julio de 2015): 147–52. http://dx.doi.org/10.4028/www.scientific.net/kem.655.147.

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In this study, the (Mn, Sb) co-tuned PbCa0.01[(MnxZn0.1-x)1/3(SbxNb0.1-x)2/3 (Zr0.505Ti0.4895)0.9]O3 (PCZMNSZT-100x) ceramics were prepared near the morphotropic phase boundary (MPB) using the wolframite precursor method. The phase structure evolutions, electrical and temperature stability properties were systematically investigated. As the fraction of rhombohedral phase increases, the degree of disorder in the diffused phase transition (DPT) correspondingly increased and the “hard” piezoelectric characterization would be enhanced. Moreover, the temperature change rate of k, Qm and fr can be tuned by adjusting the x content. The specimens with x=0.08 exhibit the obtained values as kp ~ 0.50, kt ~ 0.52, Qm ~ 1550, and the low temperature change rate of properties having Δfr/fr = -0.02% and ΔQm/Qm = 10.5%, up to 100 °C. To evaluate the material feasibility, the proposed multi-bulk step-down transformers using a ring/dot structure are fabricated. Their obtained electrical properties have a maximum efficiency of 92% with an output power of 15 W, a voltage gain of 0.68 and a nearly zero temperature change rate of resonant frequency are found at the load of 100 Ω.

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50

Hantke, R. "Zur Talgeschichte zwischen Domodossola und Locarno : Valle d'Ossola, Val Vigezzo (Prov. di Novara) - Centovalli (Kt. Tessin) : 1. Teil". Geographica Helvetica 42, n.º 1 (31 de marzo de 1987): 15–26. http://dx.doi.org/10.5194/gh-42-15-1987.

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Abstract. In the Miocene, the drainage of the upperToce river with the Antrona, Ogliana di Pozzolo and Vigezzo Valleys as southernmost source branches, took place northwards to the Gries and Grimsel passes. As a Miocene Aar river, the upperToce deposited in the Swiss Lowland – as gravels testify – the Molasse fan of the Napf mountain area. The continental divide was located between Monte Rosa and Gotthard farther south, in the Ossola valley between Domodossola and the Anza river mouth, in the Vigezzo tributaries near Malesco. In the younger Miocene the forming of the Helvetic nappes at the Pennine front, their advance and sliding northwards with uplif ting of the Aar massif interrupted this river course: the drainage was reversed. At the former divide S of Domodossola a lake was dammed. Along joints its outlet, eut the rock bar. From the rising Monte Rosa it took up the Anza river and followed its lower course. During cool phases, first at the Miocene/Pliocene boundary, the Toce glacier entered the Vigezzo Valley. From LocarnoTicino ice entered the lowermost Maggia valley and directed Maggia and Onsernone ice into the Centovalli. Therefore the Vigezzo ice was pushed to the southern slope. It could only reach the Ticino glacier as a small ice flow with reduced erosion power. BesideWürmian moraines and erratic boulders, the maximum extension of the north-alpine glaciers gives indications of older maximum stages also in the south-alpine areas. Uppermost carved rocks and transfluences in the Vigezzo valley show the highest ice level at 1900 m in Rissian, Mindelian or even older glacial times, at 1700 m in Würmian. From Malesco Vigezzo ice flowed over the Finero pass to the SE and reached the Ticino glacier. From the Lago Maggiore basinTicino ice entered the lowermost Cannobina valley, dammed the overflowed Vigezzo ice and caused the formation of roches moutonnées. Rissian tili, cemented debris flows, interglacial lake deposits with a thermophilous flora, overlying Würmian gravel and tili represent the Pleistocene sequence in the Vigezzo valley filling. The youngest deepening of the Melezzo river ends in Rissian tili. Still in the early late-Würmian,Toce ice entered the Vigezzo valley as far as Malesco and took up the Melezzo and Loana glaciers. From the Gridone mountain hanging glacier tongues descended into the Centovalli; Onsernone, Maggia and Ticino glaciers had became independent.

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