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Sample records for biological sub-micron thickness

  1. Characterization of in-situ annealed sub-micron thick Cu(In,Ga)Se{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Byoung-Soo; Sung, Shi-Joon; Hwang, Dae-Kue, E-mail: dkhwang@dgist.ac.kr

    2015-09-01

    Sub-micron thick Cu(In,Ga)Se{sub 2} (CIGS) thin films were deposited on Mo-coated soda-lime glass substrates under various conditions by single-stage co-evaporation. Generally, the short circuit current (J{sub sc}) decreased with the decreasing thickness of the absorber layer. However, in this study, J{sub sc} was nearly unchanged with decreasing thickness, while the open circuit voltage (V{sub oc}) and fill factor (FF) decreased by 31.9 and 31.1%, respectively. We believe that the remarkable change of V{sub oc} and FF can be attributed to the difference in the total amount of injected thermal energy. Using scanning electron microscopy, we confirmed that the surface morphology becomes smooth and the grain size increased after the annealing process. In the X-ray diffraction patterns, the CIGS thin film also showed an improved crystal quality. We observed that the electric properties were improved by the in-situ annealing of CIGS thin films. The reverse saturation current density of the annealed CIGS solar cell was 100 times smaller than that of reference solar cell. Thus, sub-micron CIGS thin films annealed under a constant Se rate showed a 64.7% improvement in efficiency. - Highlights: • The effects of in-situ annealing the sub-micron CIGS film have been investigated. • The surface morphology and the grain size were improved by in-situ annealing. • The V{sub oc} and FF of the films were increased by about 30% after in-situ annealing. • In-situ annealing of sub-micron thick CIGS films can be improved an efficiency.

  2. Free-Standing Organic Transistors and Circuits with Sub-Micron Thicknesses

    Science.gov (United States)

    Fukuda, Kenjiro; Sekine, Tomohito; Shiwaku, Rei; Morimoto, Takuya; Kumaki, Daisuke; Tokito, Shizuo

    2016-06-01

    The realization of wearable electronic devices with extremely thin and flexible form factors has been a major technological challenge. While substrates typically limit the thickness of thin-film electronic devices, they are usually necessary for their fabrication and functionality. Here we report on ultra-thin organic transistors and integrated circuits using device components whose substrates that have been removed. The fabricated organic circuits with total device thicknesses down to 350 nm have electrical performance levels close to those fabricated on conventional flexible substrates. Moreover, they exhibit excellent mechanical robustness, whereby their static and dynamic electrical characteristics do not change even under 50% compressive strain. Tests using systematically applied compressive strains reveal that these free-standing organic transistors possess anisotropic mechanical stability, and a strain model for a multilayer stack can be used to describe the strain in this sort of ultra-thin device. These results show the feasibility of ultimate-thin organic electronic devices using free-standing constructions.

  3. Quantitative trace element analysis with sub-micron lateral resolution

    International Nuclear Information System (INIS)

    In recent years many nuclear microprobes have developed to sophisticated tools for elemental analysis with high resolutions down to about 1 μm micron. The application to trace element analysis is mainly in the field of biological and medical research. Numerous successful studies on microscopic scale structures, e.g. cells, lead to the demand for higher spatial resolution or lower detection limits. Therefore, several labs started new efforts for sub-micron resolutions, sometimes intending 100 nm. The Leipzig microprobe laboratory LIPSION has recently improved its analytical capabilities. We are now able to perform quantitative trace element analysis with sub-micron spatial resolution (beam diameter 0.5 μm at 120 pA). As an example we give the trace element distribution in neuromelanin (intracellular pigment of neurons). Furthermore, when the scan size is reduced from cellular level, i.e. about 50 μm, to sub-cellular level of about 10 μm, the beam diameter can further be reduced by choosing smaller object diaphragms. The unavoidable reduction in beam current will not affect the mapping sensitivity unless the accumulated charge per spatial resolution is not decreased. The smallest beam diameter with analytical capabilities for elemental analysis we achieved thus far was about 300 nm in diameter. It enables an outstanding microPIXE resolution. However, some difficulties appeared in high-resolution work, which limited the acquisition time to less than 30 min

  4. Quantitative trace element analysis with sub-micron lateral resolution

    Energy Technology Data Exchange (ETDEWEB)

    Reinert, Tilo [Nukleare Festkoerperphysik, Universitaet Leipzig, Linnestr. 5, D-04103 Leipzig (Germany)]. E-mail: reinert@physik.uni-leipzig.de; Spemann, Daniel [Nukleare Festkoerperphysik, Universitaet Leipzig, Linnestr. 5, D-04103 Leipzig (Germany); Morawski, Markus [Paul-Flechsig-Institut fuer Hirnforschung, Universitaet Leipzig, Jahnallee 59, 04109 Leipzig (Germany); Arendt, Thomas [Paul-Flechsig-Institut fuer Hirnforschung, Universitaet Leipzig, Jahnallee 59, 04109 Leipzig (Germany)

    2006-08-15

    In recent years many nuclear microprobes have developed to sophisticated tools for elemental analysis with high resolutions down to about 1 {mu}m micron. The application to trace element analysis is mainly in the field of biological and medical research. Numerous successful studies on microscopic scale structures, e.g. cells, lead to the demand for higher spatial resolution or lower detection limits. Therefore, several labs started new efforts for sub-micron resolutions, sometimes intending 100 nm. The Leipzig microprobe laboratory LIPSION has recently improved its analytical capabilities. We are now able to perform quantitative trace element analysis with sub-micron spatial resolution (beam diameter 0.5 {mu}m at 120 pA). As an example we give the trace element distribution in neuromelanin (intracellular pigment of neurons). Furthermore, when the scan size is reduced from cellular level, i.e. about 50 {mu}m, to sub-cellular level of about 10 {mu}m, the beam diameter can further be reduced by choosing smaller object diaphragms. The unavoidable reduction in beam current will not affect the mapping sensitivity unless the accumulated charge per spatial resolution is not decreased. The smallest beam diameter with analytical capabilities for elemental analysis we achieved thus far was about 300 nm in diameter. It enables an outstanding microPIXE resolution. However, some difficulties appeared in high-resolution work, which limited the acquisition time to less than 30 min.

  5. The fabrication of sub-micron size cesium iodide x-ray scintillator

    Science.gov (United States)

    Hun, Chien Wan; Chen, Po Chun; Huang, Ker Jer; Chen, Chien Chon

    2015-05-01

    The cesium iodide (CsI) scintillator can converts incident X-ray into visible light with very high conversion efficiency of optical photons. The incident energy, response time, film thickness, sample size, and spatial resolution require in engineering and medical applications are difference. A smooth and flat surface and single crystal structure of CsI enhance the X-ray to visible light conversion. However, the regular CsI is soft and extremely hygroscopic; it is very difficult to polish to obtain a smooth and optical flat plane. In order to obtain a good quality of CsI scintillator for X-ray application we used an ordering channel as template and formed sub-micron CsI wire in the template. The fabrication process including: (1) Ordering structure of nano or sub-micron channels were made by an anodization method; (2) fill CsI scintillated film on the channel by CsI solution, (3) fill CsI melt into the channel formation single crystal of sub-micron crystalline scintillator after solidification. The non-vacuum processes of anodization and solidication methods were used for the sub-micron CsI scintillator column formation that is cost down the scintillator fabrication. In addition, through the fabrication method, the ordering structure scintillator of scintillator can be made by anodic treatment and die casting technology with low cost and rapid production; moreover, the film oxidized metal tubes of the tubular template can be further manufactured to nano tubes by adjusting electrolyte composition, electrolysis voltage, and processing time of anodic treatment, and the aperture size, the thickness and the vessel density of the nano tube can be controlled and ranged from 10 nm to 500 nm, 0.1 μm to 1000 μm, and hundred million to thousand billion tube/cm2, respectively.

  6. Sub-micron silica diaphragm-based fiber-tip Fabry-Perot interferometer for pressure measurement.

    Science.gov (United States)

    Liao, Changrui; Liu, Shen; Xu, Lei; Wang, Chao; Wang, Yiping; Li, Zhengyong; Wang, Qiao; Wang, D N

    2014-05-15

    We demonstrate a sub-micron silica diaphragm-based fiber-tip Fabry-Perot interferometer for pressure sensing applications. The thinnest silica diaphragm, with a thickness of ∼320  nm, has been achieved by use of an improved electrical arc discharge technique. Such a sub-micron silica diaphragm breaks the sensitivity limitation imposed by traditional all-silica Fabry-Perot interferometric pressure sensors and, as a result, a high pressure sensitivity of ∼1036  pm/MPa at 1550 nm and a low temperature cross-sensitivity of ∼960  Pa/°C are achieved when a silica diaphragm of ∼500  nm in thickness is used. Moreover, the all-silica spherical structure enhanced the mechanical strength of the micro-cavity sensor, making it suitable for high sensitivity pressure sensing in harsh environments.

  7. Discovering sub-micron ice particles across Dione' surface

    Science.gov (United States)

    Scipioni, Francesca; Schenk, Pual; Tosi, Federico; Clark, Roger; Dalle Ore, Cristina; Combe, Jean-Philippe

    2015-11-01

    Water ice is the most abundant component of Saturn’s mid-sized moons. However, these moons show an albedo asymmetry - their leading sides are bright while their trailing side exhibits dark terrains. Such differences arise from two surface alteration processes: (i) the bombardment of charged particles from the interplanetary medium and driven by Saturn’s magnetosphere on the trailing side, and (ii) the impact of E-ring water ice particles on the satellites’ leading side. As a result, the trailing hemisphere appears to be darker than the leading side. This effect is particularly evident on Dione's surface. A consequence of these surface alteration processes is the formation or the implantation of sub-micron sized ice particles.The presence of such particles influences and modifies the surfaces' spectrum because of Rayleigh scattering by the particles. In the near infrared range of the spectrum, the main sub-micron ice grains spectral indicators are: (i) asymmetry and (ii) long ward minimum shift of the absorption band at 2.02 μm (iii) a decrease in the ratio between the band depths at 1.50 and 2.02 μm (iv) a decrease in the height of the spectral peak at 2.6 μm (v) the suppression of the Fresnel reflection peak at 3.1 μm and (vi) the decrease of the reflection peak at 5 μm relative to those at 3.6 μm.We present results from our ongoing work mapping the variation of sub-micron ice grains spectral indicators across Dione' surface using Cassini-VIMS cubes acquired in the IR range (0.8-5.1 μm). To characterize the global variations of spectral indicators across Dione' surface, we divided it into a 1°x1° grid and then averaged the band depths and peak values inside each square cell.We will investigate if there exist a correspondence with water ice abundance variations by producing water ice' absorption band depths at 1.25, 1.52 and 2.02 μm, and with surface morphology by comparing the results with ISS color maps in the ultraviolet, visible and infrared

  8. STEM tomography for thick biological specimens

    Energy Technology Data Exchange (ETDEWEB)

    Aoyama, Kazuhiro [FEI Company Japan Ltd., Application Laboratory, NSS-II Building, 2-13-34 Kohnan, Minato-ku, Tokyo 108-0075 (Japan)], E-mail: kazuhiro.aoyama@fei.com; Takagi, Tomoko [FEI Company Japan Ltd., Application Laboratory, NSS-II Building, 2-13-34 Kohnan, Minato-ku, Tokyo 108-0075 (Japan); Laboratory of Electron Microscopy, Japan Women' s University, 2-8-1 Mejirodai, Bunkyo-ku, Tokyo 112-8681 (Japan); Hirase, Ai; Miyazawa, Atsuo [Bio-multisome Research Team, RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); CREST, JST (Japan)

    2008-12-15

    Scanning transmission electron microscopy (STEM) tomography was applied to biological specimens such as yeast cells, HEK293 cells and primary culture neurons. These cells, which were embedded in a resin, were cut into 1-{mu}m-thick sections. STEM tomography offers several important advantages including: (1) it is effective even for thick specimens, (2) 'dynamic focusing', (3) ease of using an annular dark field (ADF) mode and (4) linear contrasts. It has become evident that STEM tomography offers significant advantages for the observation of thick specimens. By employing STEM tomography, even a 1-{mu}m-thick specimen (which is difficult to observe by conventional transmission electron microscopy (TEM)) was successfully analyzed in three dimensions. The specimen was tilted up to 73 deg. during data acquisition. At a large tilt angle, the specimen thicknesses increase dramatically. In order to observe such thick specimens, we introduced a special small condenser aperture that reduces the collection angle of the STEM probe. The specimen damage caused by the convergent electron beam was expected to be the most serious problem; however, the damage in STEM was actually smaller than that in TEM. In this study, the irradiation damage caused by TEM- and STEM-tomography in biological specimens was quantitatively compared.

  9. Numerical Investigation of Evaporation Induced Self-Assembly of Sub-Micron Particles Suspended in Water

    OpenAIRE

    Tayeb, Raihan; Mao, Yijin; Zhang, Yuwen

    2016-01-01

    Self-assembly of sub-micron particles suspended in a water film is investigated numerically. The liquid medium is allowed to evaporate leaving only the sub-micron particles. A coupled CFD-DEM approach is used for the simulation of fluid-particle interaction. Momentum exchange and heat transfer between particles and fluid and among particles are considered. A history dependent contact model is used to compute the contact force among sub-micron particles. Simulation is done using the open sourc...

  10. Simulation of sub-micron particle formation and growth during combustion processes

    Institute of Scientific and Technical Information of China (English)

    WEI Feng; ZHANG Junying; ZHENG Chuguang

    2005-01-01

    Sub-micron particle formation and growth during combustion processes is very complex because of its strong uncertainty and randomness. A model to simulate the sub-micron particle formation and growth during the combustion process is developed based on the gas kinetic theory and is expressed by the vapor concentration changes and particle loading changes, which reflects effect characteristics of different mechanism (nucleation, condensation and coagulation) in particle formation processes. The developed characteristic time is used to token the three mechanisms. It is thought that environmental temperature and pressure, vapor temperature and critical pressure are important factors influencing the sub-micron particle formation and growth. The sub-micron particle formation processes under different conditions are studied and the effect characteristics of these mechanisms are analyzed, which show that the nucleation, condensation,and coagulation occur simultaneously during the sub-micron particle formation and growth process. Nucleation contributes to the sub-micron particle formation, while condensation and coagulation is helpful to the growth of the particle size.

  11. Chemical Mapping of Proterozoic Organic Matter at Sub-Micron Spatial Resolution

    Science.gov (United States)

    Oehler, Dorothy Z.; Robert, Francois; Mostefaoui, Smail; Meibom, Anders; Selo, Madeleine; McKay, David S.

    2006-01-01

    We have used a NanoSIMS ion microprobe to map sub-micron-scale distributions of carbon, nitrogen, sulfur, silicon, and oxygen in organic microfossils and laminae from the approximately 0.85 Ga Bitter Springs Formation of Australia. The data provide clues about the original chemistry of the microfossils, the silicification process, and biosignatures of specific microorganisms and microbial communities. Chemical maps of fossil unicells and filaments reveal distinct wall-and sheath-like structures enriched in C, N and S, consistent with their accepted biological origin. Surprisingly, organic laminae, previously considered to be amorphous, also exhibit filamentous and apparently compressed spheroidal structures defined by strong enrichments in C, N and S. By analogy to data from the well-preserved microfossils, these structures are interpreted as being of biological origin, most likely representing densely packed remnants of microbial mats. Because the preponderance of organic matter in Precambrian sediments is similarly "amorphous," our findings open a large body of generally neglected material to in situ structural, chemical, and isotopic study. Our results also offer new criteria for assessing biogenicity of problematic kerogenous materials and thus can be applied to assessments of poorly preserved or fragmentary organic residues in early Archean sediments and any that might occur in meteorites or other extraterrestrial samples.

  12. THREE-DIMENSIONAL ANALYSIS OF SCALE DEPENDENCE OF SUB-MICRON POLYCRYSTALS DUE TO CONFIGURATION ENTROPY

    Institute of Scientific and Technical Information of China (English)

    杨强; 杨卫

    2001-01-01

    The authors proposed a plausible explanation for the deviation of experimental data for sub-micron polycrystals from the Hall-Petch relation by in troducing the configuration entropy. The present paper extends the previous two dimensional analysis to the three-dimensional case. The statistical distribution of dislocation lengths within a spherical grain and the bow-out of dislocations are con sidered. According to Ashby's model, analyses are pursued for the statistically stored dislocations and geometrically necessary dislocations, respectively. It is confirmed that the configuration entropy model can predict the abnormal Hall-Petch depen dence for grain sizes in the sub-micron range.

  13. Analysis and Design of Monolithic Inductors in Sub-micron CMOS

    DEFF Research Database (Denmark)

    Fallesen, Carsten; Jørgensen, Allan

    1997-01-01

    of the planar inductors used in sub-micron CMOS. The model developed should be ofsuch a quality that it can be used for even very demanding circuits. The result of the model should be useable in all the normal circuit simulators used today. The model should furthermore be very fast in order to be useable...

  14. Reversal studies on sub-micron Co-Cr thin films by AHE analysis

    NARCIS (Netherlands)

    Haan, de S.; Lodder, J.C.

    1996-01-01

    In this study three Co---Cr thin films, prepared under different deposition conditions, are investigated. They have values for the coercivity (Hc) of 11, 90 and 170 kA/m, respectively. The anomalous Hall effect (AHE) has been used to record the hysteresis curves of specially prepared sub-micron Hall

  15. Numerical Investigation of Evaporation Induced Self-Assembly of Sub-Micron Particles Suspended in Water

    CERN Document Server

    Tayeb, Raihan; Zhang, Yuwen

    2016-01-01

    Self-assembly of sub-micron particles suspended in a water film is investigated numerically. The liquid medium is allowed to evaporate leaving only the sub-micron particles. A coupled CFD-DEM approach is used for the simulation of fluid-particle interaction. Momentum exchange and heat transfer between particles and fluid and among particles are considered. A history dependent contact model is used to compute the contact force among sub-micron particles. Simulation is done using the open source software package CFDEM which basically comprises of two other open source packages OpenFOAM and LIGGGHTS. OpenFOAM is a widely used solver for CFD related problems. LIGGGHTS, a modification of LAMMPS, is used for DEM simulation of granular materials. The final packing structure of the sub-micron particles is discussed in terms of distribution of coordination number and radial distribution function (RDF). The final packing structure shows that particles form clusters and exhibit a definite pattern as water evaporates awa...

  16. Selective epitaxial growth of sub-micron structures of YBaCuO by substrate modification

    NARCIS (Netherlands)

    Blank, Dave H.A.; Damen, Cas A.J.; Kropman, Boike L.; Rogalla, Horst

    1994-01-01

    Sub-micron structures of high-Tc thin films have been realized with Selective Epitaxial Growth (SEG). Two different techniques to achieve SEG have been studied. First, narrow trenches down to 100 nm are etched into the substrate with a four-layer E-beam lithography technique. Second, amorphous metal

  17. Power management of digital circuits in deep sub-micron CMOS technologies

    CERN Document Server

    Henzler, Stephan

    2006-01-01

    In the deep sub-micron regime, the power consumption has become one of the most important issues for competitive design of digital circuits. This book mainly deals with circuit design but also addresses the interface between circuit and system level design on the one side and between circuit and physical design on the other side.

  18. Generating Sub-Micron Features On Rough Surfaces Using Optical Trap Assisted Nanopatterning

    Science.gov (United States)

    Tsai, Yu-Cheng; Fardel, Romain; Arnold, Craig B.

    2010-10-01

    Near-field intensity enhancement enables laser modification of materials with feature sizes below the classical diffraction limit. However, the need to maintain close distances between the objective element and the substrate typically limit demonstrations of this technology to flat surfaces, even though there are many cases where the ability to produce sub-micron features on rough or structured surfaces are needed. Here, we show the use of a new technique, optical trap assisted nanopatterning (OTAN), for the production of nanoscale features on rippled substrates. The ability to position a microbead near-field objective close to the surface without the need for active feedback and control allows one to continuously move the bead across a rough surface without sticking. Sub-micron patterning of polyimide is demonstrated on surfaces with 1.1 μm steps showing good uniformity. Finally, the enabling technology allows for straightforward parallelization where multiple patterns can be created simultaneously over surface.

  19. Extinction spectra of quasi-spherical silver sub-micron particles

    Science.gov (United States)

    Malynych, S.; Chumanov, G.

    2007-07-01

    In this paper, we present the experimental data on the extinction spectra of aqueous suspensions of silver sub-micron particles as well as those for planar arrays of particles. The spectra of noninteracting silver particles, i.e. colloidal suspension consist of two characteristic bands: dipole at 545 nm and quadrupole at 430 nm components of the surface plasmon resonance. Presence of some fraction of silver whiskers in colloids causes broadening and tailing of the dipole component. Coating of Ag particles with Si mantle shifts plasmon resonances to the longer wavelengths. The extinction spectrum of planar array of Ag sub-micron particles self-assembled on a glass substrate drastically differs from that for colloidal suspension. The effect may arise from coherent coupling of surface plasmons associated with the particles.

  20. FABRICATION OF SILICON-ON-INSULATOR MEM RESONATORS WITH DEEP SUB-MICRON TRANSDUCTION GAPS

    OpenAIRE

    Badila, N.-D.; Hibert, C.; Mazza, M.; Ionescu, A.M.

    2006-01-01

    Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/5920) International audience The paper proposes and validates a low-cost technological process for realizing fully mono-crystalline MEM resonators with deep sub-micron transduction gaps on SOI substrates. The MEM resonators are designed to work as BLR (bulk lateral resonators) in which the resonance of a suspended mass is excited and detected by lateral electrodes. For MEM BLRs, nano-scaled gaps (

  1. Directed assembly of conducting polymers on sub-micron templates by electrical fields

    International Nuclear Information System (INIS)

    Highlights: ► Nanoscale patterns with dimensions of assembled PANi down to 100 nm were fabricated. ► We use electrophoretic and dielectrophoretic assembly to deposit PANi. ► Electrophoretic and dielectrophoretic assembly of PANi finished in less than 1 min. ► Effect of process parameters on assembly of PANi onto nanoscale pattern was studied. ► The assembled PANi can be transferred to other flexible substrates. - Abstract: Patterning of conducting polymer into sub-micron patterns over large areas at high rate and low cost is significant for commercial manufacturing of novel devices. Electrophoretic and dielectrophoretic assembly provide an easily scaled approach with high fabrication rates. In this work, electrophoretic and dielectrophoretic assembly were used to assemble polyaniline (PANi) into multiscale sub-micron size patterns in less than 1 min. The process was controlled by assembly time, amplitude, and frequency of the electric field. Dielectrophoretic assembly is preferable for manufacturing as it reduces damage to the templates used to control the assembly. Using this method, sub-micron patterns with dimensions of the assembled PANi down to 100 nm were fabricated over large areas in short times. The assembled PANi was further transferred to other flexible polymer substrates by a thermoforming process, providing a fast, easily controlled and promising approach for fabrication of nanoscale devices.

  2. Generation of sub-micron particles and secondary pollutants from building materials by ozone reaction

    Science.gov (United States)

    Aoki, Taisuke; Tanabe, Shin-ichi

    This study reports results from two different experiments examining reactions between ozone and common building materials that can lead to the formation of secondary products and particulate-phase materials. Monitored species include sub-micron particles and volatile organic compounds (VOCs). In the first set of experiments, various building materials were placed in a 20 L stainless-steel chamber and exposed to ozone. The materials included expanded polystyrene, a natural rubber adhesive, cedar board, Japanese Cyprus board and silver fir board, as well as d-limonene, which is a known constituent of certain woods and cleaning products. The combination of ozone and either d-limonene, cedar board or cypress board produced sub-micron particles, with most of the increase occurring in the size range of 0.01- 0.5μm diameter. This was not observed for the other materials. In the case of cedar board, the consequence of ozone exposure over an extended time interval was monitored. As the exposure time elapsed, the concentration of sub-micron particles moderately decreased. In the second set of experiments, unwaxed or waxed plastic tiles were placed in the 20 L chamber and exposed to ozone. Sub-micron particles and organic compounds were measured during the course of the experiments. In the case of the waxed tile, the number of 0.01- 1.0μm size particles grew about 50×108particlesm-3; particle growth was significantly less for the un-waxed tile. For both the waxed and un-waxed tiles, the emission rates of heptane, nonane, nonanal, and decanal increased after ozone was added to the supply air. (However, it is not clear if some or all of this production was due to ozone reacting with the sorbent used for sampling or with compounds captured by the sorbent.) This study provides further evidence that ozone-initiated reactions with building materials can be a significant source of both sub-micron particles and secondary organic compounds in indoor environments.

  3. Suppression of transient enhanced diffusion in sub-micron patterned silicon template by dislocation loops formation

    Science.gov (United States)

    Hu, Kuan-Kan; Chang, Ruey-Dar; Woon, Wei Yen

    2015-10-01

    We investigate the evolution of two dimensional transient enhanced diffusion (TED) of phosphorus in sub-micron scale patterned silicon template. Samples doped with low dose phosphorus with and without high dose silicon self-implantation, were annealed for various durations. Dopant diffusion is probed with plane-view scanning capacitance microscopy. The measurement revealed two phases of TED. Significant suppression in the second phase TED is observed for samples with high dose self-implantation. Transmission electron microscopy suggests the suppressed TED is related to the evolution of end of range defect formed around ion implantation sidewalls.

  4. Suppression of transient enhanced diffusion in sub-micron patterned silicon template by dislocation loops formation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Kuan-Kan; Woon, Wei Yen [Department of Physics, National Central University, Jungli, 32054, Taiwan (China); Chang, Ruey-Dar [Chang Gung University, Taoyuan, Taiwan 33302 (China)

    2015-10-15

    We investigate the evolution of two dimensional transient enhanced diffusion (TED) of phosphorus in sub-micron scale patterned silicon template. Samples doped with low dose phosphorus with and without high dose silicon self-implantation, were annealed for various durations. Dopant diffusion is probed with plane-view scanning capacitance microscopy. The measurement revealed two phases of TED. Significant suppression in the second phase TED is observed for samples with high dose self-implantation. Transmission electron microscopy suggests the suppressed TED is related to the evolution of end of range defect formed around ion implantation sidewalls.

  5. Suppression of transient enhanced diffusion in sub-micron patterned silicon template by dislocation loops formation

    Directory of Open Access Journals (Sweden)

    Kuan-Kan Hu

    2015-10-01

    Full Text Available We investigate the evolution of two dimensional transient enhanced diffusion (TED of phosphorus in sub-micron scale patterned silicon template. Samples doped with low dose phosphorus with and without high dose silicon self-implantation, were annealed for various durations. Dopant diffusion is probed with plane-view scanning capacitance microscopy. The measurement revealed two phases of TED. Significant suppression in the second phase TED is observed for samples with high dose self-implantation. Transmission electron microscopy suggests the suppressed TED is related to the evolution of end of range defect formed around ion implantation sidewalls.

  6. Environmental behavior and stress corrosion characteristics of nano/sub-micron E950 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    Aghion, Eli; Guinguis, Inbar [Department of Materials Engineering, Ben-Gurion University of the Negev Beer-Sheva (Israel)

    2009-11-15

    The corrosion performance and stress corrosion resistance of E950 Aluminum alloy with nano/sub-micron structure were evaluated in 3.5% NaCl solution. The results obtained indicated that the corrosion and stress corrosion resistance of E950 alloy were relatively reduced compared to that of the conventional coarse-grained alloy (Al-4.65%Mg). In particular, the inherently improved ultimate tensile strength of E950 alloy was significantly decreased under stress corrosion conditions. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  7. X-Ray Powder Diffraction from Sub-Micron Crystals of Photosystem-1 Membrane Protein

    OpenAIRE

    Shapiro, D. A.; DePonte, D.; Doak, R. B.; Fromme, P.; Hembree, G.; Hunter, M; Marchesini, S.; Schmidt, K.; Starodub, D.; Weierstall, U.; Chapman, H.; Spence, J

    2008-01-01

    We demonstrate that powder diffraction data can be collected from sub-micron crystals of a mbrane protein with nearly two orders of magnitude more atoms than the molecules commonly used for powder diffraction. The crystals of photosystem-1 protein were size-selected using a 500 nm pore- size filter and delivered to a soft x-ray beam with a photon energy of 1.5 keV using a dynamically focused micro-jet developed for the serial crystallography experiment at beamline 9.0.1. The 10-micron jet pla...

  8. The Deposition and removal of sub-micron particles of magnetite at the surface of alloy 800

    International Nuclear Information System (INIS)

    The rate of isothermal deposition of sub-micron particles of magnetite onto the surface of alloy 800 has been measured at pH between 4.2 and 9.3 at Re=10 000 and a fluid temperature of 25 degrees C. Deposition is modelled as a two-step process: transport of particles to the surface region followed by attachment to the surface. The deposition is limited by particle transport between pH 6.5 and 8.3, and by the rate of attachment for pH outside of that range. The rate of attachment has an Arrhenius dependence on surface temperature with an activation energy of 42 kJ/mole at pH 9.3. The rate of particle removal was negligible compared to the deposition rate, probably because the thickness of the viscous sub-layer was very much greater than the particle size. (author). 19 refs., 1 tab., 6 figs

  9. Laser smoothing of sub-micron grooves in hydroxyl-rich fused silica

    International Nuclear Information System (INIS)

    Nano- to micrometer-sized surface defects on UV-grade fused silica surfaces are known to be effectively smoothed through the use of high-temperature localized CO2 laser heating, thereby enhancing optical properties. However, the details of the mass transport and the effect of hydroxyl content on the laser smoothing of defective silica at sub-micron length scales are still not completely understood. In this study, we examine the morphological evolution of sub-micron, dry-etched periodic surface structures on type II and type III SiO2 substrates under 10.6 μm CO2 laser irradiation using atomic force microscopy (AFM). In situ thermal imaging was used to map the transient temperature field across the heated region, allowing assessment of the T-dependent mass transport mechanisms under different laser-heating conditions. Computational fluid dynamics simulations correlated well with experimental results, and showed that for large effective capillary numbers (Nc > 2), surface diffusion is negligible and smoothing is dictated by capillary action, despite the relatively small spatial scales studied here. Extracted viscosity values over 1700-2000 K were higher than the predicted bulk values, but were consistent with the surface depletion of OH groups, which was confirmed using confocal Raman microscopy.

  10. Kinetics of Sub-Micron Grain Size Refinement in 9310 Steel

    Science.gov (United States)

    Kozmel, Thomas; Chen, Edward Y.; Chen, Charlie C.; Tin, Sammy

    2014-05-01

    Recent efforts have focused on the development of novel manufacturing processes capable of producing microstructures dominated by sub-micron grains. For structural applications, grain refinement has been shown to enhance mechanical properties such as strength, fatigue resistance, and fracture toughness. Through control of the thermo-mechanical processing parameters, dynamic recrystallization mechanisms were used to produce microstructures consisting of sub-micron grains in 9310 steel. Starting with initial bainitic grain sizes of 40 to 50 μm, various levels of grain refinement were observed following hot deformation of 9310 steel samples at temperatures and strain rates ranging from 755 K to 922 K (482 °C and 649 °C) and 1 to 0.001/s, respectively. The resulting deformation microstructures were characterized using scanning electron microscopy and electron backscatter diffraction techniques to quantify the extent of carbide coarsening and grain refinement occurring during deformation. Microstructural models based on the Zener-Holloman parameter were developed and modified to include the effect of the ferrite/carbide interactions within the system. These models were shown to effectively correlate microstructural attributes to the thermal mechanical processing parameters.

  11. Time-specific measurements of energy deposition from radiation fields in simulated sub-micron tissue volumes

    Energy Technology Data Exchange (ETDEWEB)

    Famiano, M.A.

    1997-07-07

    A tissue-equivalent spherical proportional counter is used with a modified amplifier system to measure specific energy deposited from a uniform radiation field for short periods of time ({approximately}1 {micro}s to seconds) in order to extrapolate to dose in sub-micron tissue volumes. The energy deposited during these time intervals is compared to biological repair processes occurring within the same intervals after the initial energy deposition. The signal is integrated over a variable collection time which is adjusted with a square-wave pulse. Charge from particle passages is collected on the anode during the period in which the integrator is triggered, and the signal decays quickly to zero after the integrator feedback switch resets; the process repeats for every triggering pulse. Measurements of energy deposited from x rays, {sup 137}Cs gamma rays, and electrons from a {sup 90}Sr/{sup 90}Y source for various time intervals are taken. Spectral characteristics as a function of charge collection time are observed and frequency plots of specific energy and collection time-interval are presented. In addition, a threshold energy flux is selected for each radiation type at which the formation of radicals (based on current measurements) in mammalian cells equals the rate at which radicals are repaired.

  12. Time-specific measurements of energy deposition from radiation fields in simulated sub-micron tissue volumes

    International Nuclear Information System (INIS)

    A tissue-equivalent spherical proportional counter is used with a modified amplifier system to measure specific energy deposited from a uniform radiation field for short periods of time (∼1 micros to seconds) in order to extrapolate to dose in sub-micron tissue volumes. The energy deposited during these time intervals is compared to biological repair processes occurring within the same intervals after the initial energy deposition. The signal is integrated over a variable collection time which is adjusted with a square-wave pulse. Charge from particle passages is collected on the anode during the period in which the integrator is triggered, and the signal decays quickly to zero after the integrator feedback switch resets; the process repeats for every triggering pulse. Measurements of energy deposited from x rays, 137Cs gamma rays, and electrons from a 90Sr/90Y source for various time intervals are taken. Spectral characteristics as a function of charge collection time are observed and frequency plots of specific energy and collection time-interval are presented. In addition, a threshold energy flux is selected for each radiation type at which the formation of radicals (based on current measurements) in mammalian cells equals the rate at which radicals are repaired

  13. Deformation Behavior of Sub-micron and Micron Sized Alumina Particles in Compression.

    Energy Technology Data Exchange (ETDEWEB)

    Sarobol, Pylin; Chandross, Michael E.; Carroll, Jay; Mook, William; Boyce, Brad; Kotula, Paul Gabriel; McKenzie, Bonnie Beth; Bufford, Daniel Charles; Hall, Aaron Christopher.

    2014-09-01

    The ability to integrate ceramics with other materials has been limited due to high temperature (>800degC) ceramic processing. Recently, researchers demonstrated a novel process , aerosol deposition (AD), to fabricate ceramic films at room temperature (RT). In this process, sub - micro n sized ceramic particles are accelerated by pressurized gas, impacted on the substrate, plastically deformed, and form a dense film under vacuum. This AD process eliminates high temperature processing thereby enabling new coatings and device integration, in which ceramics can be deposited on metals, plastics, and glass. However, k nowledge in fundamental mechanisms for ceramic particle s to deform and form a dense ceramic film is still needed and is essential in advancing this novel RT technology. In this wo rk, a combination of experimentation and atomistic simulation was used to determine the deformation behavior of sub - micron sized ceramic particle s ; this is the first fundamental step needed to explain coating formation in the AD process . High purity, singl e crystal, alpha alumina particles with nominal size s of 0.3 um and 3.0 um were examined. Particle characterization, using transmission electron microscopy (TEM ), showed that the 0.3 u m particles were relatively defect - free single crystals whereas 3.0 u m p articles were highly defective single crystals or particles contained low angle grain boundaries. Sub - micron sized Al 2 O 3 particles exhibited ductile failure in compression. In situ compression experiments showed 0.3um particles deformed plastically, fractured, and became polycrystalline. Moreover, dislocation activit y was observed within the se particles during compression . These sub - micron sized Al 2 O 3 particles exhibited large accum ulated strain (2 - 3 times those of micron - sized particles) before first fracture. I n agreement with the findings from experimentation , a tomistic simulation s of nano - Al 2 O 3 particles showed dislocation slip and

  14. Occurrence of weak, sub-micron, tropospheric aerosol events at high Arctic latitudes

    Science.gov (United States)

    O'Neill, N. T.; Pancrati, O.; Baibakov, K.; Eloranta, E.; Batchelor, R. L.; Freemantle, J.; McArthur, L. J. B.; Strong, K.; Lindenmaier, R.

    2008-07-01

    Numerous fine mode (sub-micron) aerosol optical events were observed during the summer of 2007 at the High Arctic atmospheric observatory (PEARL) located at Eureka, Nunavut, Canada. Half of these events could be traced to forest fires in southern and eastern Russia and the Northwest Territories of Canada. The most notable findings were that (a) a combination of ground-based measurements (passive sunphotometry, high spectral resolution lidar) could be employed to determine that weak (near sub-visual) fine mode events had occurred, and (b) this data combined with remote sensing imagery products (MODIS, OMI-AI, FLAMBE fire sources), Fourier transform spectroscopy and back trajectories could be employed to identify the smoke events.

  15. An all-optical modulation method in sub-micron scale.

    Science.gov (United States)

    Yang, Longzhi; Pei, Chongyang; Shen, Ao; Zhao, Changyun; Li, Yan; Li, Xia; Yu, Hui; Li, Yubo; Jiang, Xiaoqing; Yang, Jianyi

    2015-01-01

    We report a theoretical study showing that by utilizing the illumination of an external laser, the Surface Plasmon Polaritons (SPP) signals on the graphene sheet can be modulated in the sub-micron scale. The SPP wave can propagate along the graphene in the middle infrared range when the graphene is properly doped. Graphene's carrier density can be modified by a visible laser when the graphene sheet is exfoliated on the hydrophilic SiO2/Si substrate, which yields an all-optical way to control the graphene's doping level. Consequently, the external laser beam can control the propagation of the graphene SPP between the ON and OFF status. This all-optical modulation effect is still obvious when the spot size of the external laser is reduced to 400 nm while the modulation depth is as high as 114.7 dB/μm. PMID:25777581

  16. Powder Diffraction from a Continuous Micro-Jet of sub-micron Protein Crystals

    CERN Document Server

    Shapiro, D A; Doak, R B; Fromme, P; Hembree, G; Hunter, M; Marchesini, S; Schmidt, K; Starodub, D; Weierstall, U; Chapman, H; Spence, J

    2008-01-01

    Powder diffraction rings have been obtained from sub-micron protein crystallites in a water jet, and the data analysed. Previous powder diffraction has used a suspension of small crystallites, and long exposures, causing significant X-ray damage. We show here that protein powder data from nano-crystals can be obtained using a continuous micro-jet. This allows more efficient use of crystal growth solutions containing nanocrystals and the much shorter exposures needed for next-generation synchrotrons. This method requires neither the crushing of larger polycrystalline samples nor any techniques to avoid radiation damage such as cryo-cooling. We have commissioned an apparatus to record protein powder diffraction in this manner and in this paper present the first such patterns from photosystem I protein crystals with sizes less than 500 nm. These preliminary patterns show the lowest order reflections, which agree quantitatively with theoretical calculations of the powder profile. The results serve also to test ou...

  17. Large-Quantity Synthesis of Single-Crystalline Metal Indium Nano/Sub-Micron Wires

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yang; SHAN Xu-Dong; LIAO Zhi-Min; ZHAO Qing; XU Jun; YU Da-Peng

    2008-01-01

    Large quantities of metal indium single-crystalline wires with diameters ranging from tens of nanometres to a few micrometres were synthesized on Si substrates.Unlike traditional methods for the fabrication of nanowires or nanorods,liquid indium was squeezed out of the pores and cracks from porous an InAlN layer to form the wires.Continuous pushing out of liquid metal indium under strength,lowenng of liquid-solid interfaces and the confinement of the cracks all contribute to the growth of indium wires.Our experiments have shed some light on the possibility of synthesizing large quantities quasi-lD nano/sub-micron structures with specified cross-sectional geometry using the similar method.

  18. Experimental research of SEU and SEL in high density SRAMs with sub-micron feature sizes

    International Nuclear Information System (INIS)

    The aggressive downscaling of CMOS technology has resulted in that radiation induced single event upset (SEU) reliability is getting worse and worse. Using the HI-13 tandem accelerator in China Institute of Atomic Energy, heavy ion SEU and single event latch-up (SEL) sensitivities for a variety of non-hardened high density static random access memories (SRAMs) with sub-micron feature sizes were reported. The results were compared with previously measured sensitivities for similar devices with larger features. The problems associated with SEU become more sever as device dimensions decrease. Multiple-bit upsets (MBU) for the HM62V16100LT15 in 0.13 μm CMOS technology caused by a single ion were analyzed. The frequency and the distribution of MBU were given. MBU makes challenge for EDAC adopted by the system of satellites. (authors)

  19. Infrared Response of Sub-Micron-Scale Structures of Polyoxymethylene: Surface Polaritons in Polymers.

    Science.gov (United States)

    Nagai, Naoto; Okawara, Makoto; Kijima, Yuta

    2016-08-01

    An investigation of the infrared (IR) spectra of polyoxymethylene (POM) mold plates was undertaken to determine the sub-micron-scale morphology and molecular orientation. The nest-structured cells concerned with the orientation were observed from scanning electron microscope (SEM) measurements with the aid of Raman spectroscopy. The intensity of the anomalous IR reflectance peak of the C-O stretching A2 mode depends on the widths of the POM layers in the SEM image along the orientation direction. The results suggest that the spectral features originate from the Berreman effect of the bulk polaritons and the radiative surface polaritons. Moreover, the IR spectra of certain treated samples suggest that enhancement of the electromagnetic fields from the gap modes and transition dipole-dipole coupling influence the spectral shapes. PMID:27469531

  20. Hot carrier degradation and a new lifetime prediction model in ultra-deep sub-micron pMOSFET

    Institute of Scientific and Technical Information of China (English)

    Lei Xiao-Yi; Liu Hong-Xia; Zhang Kai; Zhang Yue; Zheng Xue-Feng; Ma Xiao-Hua; Hao Yue

    2013-01-01

    The hot carrier effect (HCE) of an ultra-deep sub-micron p-channel metal-oxide semiconductor field-effect transistor (pMOSFET) is investigated in this paper.Experiments indicate that the generation of positively charged interface states is the predominant mechanism in the case of the ultra-deep sub-micron pMOSFET.The relation of the pMOSFET hot carrier degradation to stress time (t),channel width (W),channel length (L),and stress voltage (Vd) is then discussed.Based on the relation,a lifetime prediction model is proposed,which can predict the lifetime of the ultra-deep sub-micron pMOSFET accurately and reflect the influence of the factors on hot carrier degradation directly.

  1. Spectral bluing on 101955 Bennu and implications for dynamics of sub micron regolith grains on asteroids

    Science.gov (United States)

    Brown, Adrian J.

    2015-11-01

    C and B class asteroids (including 101955 Bennu, the destination of the OSIRIS REx mission) display spectral bluing in the visible (Lantz et al. 2013). This spectral bluing effect has been found to be temporally variable on Bennu (Binzel et al. 2015). Binzel et al. suggested this is due to a fining of the ~45 micron grain size fraction, which causes spectral reddening. This finer grain size of the ~45 micron fraction may be associated with regolith migration during formation of Bennu's equatorial ridge.In Brown (2014) the effect of grain size and optical index on the albedo of small conservative and absorbing particles as a function of wavelength was examined. The conditions necessary for maximization of spectral bluing effects in real-world situations were identified.The spectral bluing to be discussed in this presentation was present in the Lantz et al. spectra, but not the Binzel et al. spectra, suggesting that in addition to finer grain ~45 micron material, a decrease in the sub micron grain sized fraction has taken place as Bennu's sub-Earth latitude changed between these observations. Observations of this effect may provide the strongest test yet for cohesive regolith models (e.g. Rositis et al. 2014).In this presentation, I will discuss: 1.) the evidence for spectral bluing on 101955 Bennu (in particular) and other bodies in our solar system and 2.) the implications of how the OVIRS instrument on OSIRIS-REx may be used to determine the spatial variability of this spectral feature on Bennu and 3.) the potential for OVIRS to augment our understanding of the dynamics of sub micron material on asteroids.Refs:Binzel, R. P. et al. "Spectral slope variations for OSIRIS-REx target Asteroid (101955) Bennu: Possible evidence for a fine-grained regolith equatorial ridge" Icarus 256 (2015), 22-29Brown, Adrian J. “Spectral Bluing Induced by Small Particles under the Mie and Rayleigh Regimes.” Icarus 239 (2014): 85-95.Lantz, C., et al. “Evidence for the Effects of

  2. The evaluation of microstructure and mechanical properties of sintered sub-micron WC-Co powders

    International Nuclear Information System (INIS)

    A cemented tungsten carbide (WC-Co) is widely used for a variety of machining, cutting, drilling and other applications. The properties of this tungsten heavy alloy are sensitive to processing and degraded by residual porosity. The sequence of high end powder metallurgy process include mixing, compacting and followed by multi-atmosphere sintering of green compact were analyzed. The sub micron (<1.0 μm) and less than 10.0 μm of WC powders are sintered with a metal binder 6% Co to provide pore-free part. The powder compacts were sintered at temperatures cycle in the range of 1200 degree Celsius-1550 degree Celsius in nitrogen-based sintering atmosphere. To date, however there have been few reported studies in the literature that the best sintering was carried out via liquid phase sintering in vacuum at approximately 1500 degree Celsius. from this study we found that in order to attain high mechanical properties, a fine grain size of powder is necessary. Therefore, the attention of this work is to develop and produce wear resistant component with better properties or comparable to the commercial ones. (author)

  3. Polydimethylsiloxane (PDMS Sub-Micron Traps for Single-Cell Analysis of Bacteria

    Directory of Open Access Journals (Sweden)

    Dietrich Kohlheyer

    2013-10-01

    Full Text Available Microfluidics has become an essential tool in single-cell analysis assays for gaining more accurate insights into cell behavior. Various microfluidics methods have been introduced facilitating single-cell analysis of a broad range of cell types. However, the study of prokaryotic cells such as Escherichia coli and others still faces the challenge of achieving proper single-cell immobilization simply due to their small size and often fast growth rates. Recently, new approaches were presented to investigate bacteria growing in monolayers and single-cell tracks under environmental control. This allows for high-resolution time-lapse observation of cell proliferation, cell morphology and fluorescence-coupled bioreporters. Inside microcolonies, interactions between nearby cells are likely and may cause interference during perturbation studies. In this paper, we present a microfluidic device containing hundred sub-micron sized trapping barrier structures for single E. coli cells. Descendant cells are rapidly washed away as well as components secreted by growing cells. Experiments show excellent growth rates, indicating high cell viability. Analyses of elongation and growth rates as well as morphology were successfully performed. This device will find application in prokaryotic single-cell studies under constant environment where by-product interference is undesired.

  4. Detection, imaging, and kinetics of sub-micron organelles of chondrocytes by multiple beam interference microscopy

    Science.gov (United States)

    Joshi, Narahari V.; Medina, Honorio; Barboza, J. M.; Colantuoni, Gladys; Quintero, Maritza

    2004-07-01

    Chondrocytes, obtained from testosterone treated human articular cartilage, were examined by a recently developed Multiple Beam Interference Microscopy (MBIM) attached to a confocal set up, Video-enhanced differential interference microphotography and also by cinematography. In the MBIM, the intensity of the transmitted pattern is given by the Airy function which increases the contrast dramatically as the coefficient of the reflectance of the parallel plates increases. Moreover, in this configuration, the beam passes several times through a specific organelle and increases its optical path difference both because of the increase in the trajectory and refractive index (high density) of the organelle. The improved contrast enhances the resolving power of the system and makes visible several structural details of sub micron dimensions like nucleolus, retraction fibers, podia, etc. which are not possible to reveal with such a clarity by conventional techniques such as bright field, phase contrast or DIC. This technique permits to detect the oscillatory and rotational motions of unstained cilia for the first time. The frequency of oscillations was found to be 0.8 Hz.

  5. Fluidization of nano and sub-micron powders using mechanical vibration

    Institute of Scientific and Technical Information of China (English)

    Souresh Kaliyaperumal; Shahzad Barghi; Lauren Briens; Sohrab Rohani; Jesse Zhu

    2011-01-01

    The fluidization behavior of nano and sub-micron powders belonging to group C of Geldart's classification was studied in a mechanically vibrated fluidized bed (vibro-fluidized bed) at room temperature.Pretreated air was used as the fluidizing gas whereas SiO2, Al2O3, TiO2, ZrSi, BaSO4 were solid particles.Mechanical vibration amplitudes were 0.1, 0.25, 0.35, 0.45 mm, while the frequencies were 5, 20, 30,40 Hz to investigate the effects of frequency and amplitude of mechanical vibration on minimum fluidization velocity, bed pressure drop, bed expansion, and the agglomerate size and size distribution. A novel technique was employed to determine the apparent minimum fluidization velocity from pressure drop signals. Richardson-Zaki equation was employed as nano-particles showed fluid like behavior when fluidized. The average size of agglomerates formed on top of the bed was smaller than those at the bottom.Size distribution of agglomerates on top was also more uniform compared to those near the distributor.Larger agglomerates at the bottom of the bed formed a small fraction of the bed particles. Average size of submicron agglomerates decreased with increasing the frequency of vibration, however nano particles were less sensitive to change in vibration frequency. Mechanical vibration enhanced the quality of fluidization by reducing channeling and rat-holing phenomena caused by interparticle cohesive forces.

  6. Scalable Sub-micron Patterning of Organic Materials Toward High Density Soft Electronics.

    Science.gov (United States)

    Kim, Jaekyun; Kim, Myung-Gil; Kim, Jaehyun; Jo, Sangho; Kang, Jingu; Jo, Jeong-Wan; Lee, Woobin; Hwang, Chahwan; Moon, Juhyuk; Yang, Lin; Kim, Yun-Hi; Noh, Yong-Young; Jaung, Jae Yun; Kim, Yong-Hoon; Park, Sung Kyu

    2015-09-28

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. In this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. The successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics.

  7. Conformational transitions of cytochrome c in sub-micron-sized capsules at air/buffer interface.

    Science.gov (United States)

    Jaganathan, Maheshkumar; Dhathathreyan, Aruna

    2014-09-30

    This work presents the design of sub-micron-sized capsules of Cytochrome c (cyt c) in the range 300-350 nm and the conformational transitions of the protein that occur when the films of these capsules spread at the air/buffer interface are subjected to repeated compression-expansion cycles. Steady state fluorescence, time-resolved fluorescence, and circular dichroic (CD) spectra have been used to study the highly compact native conformation (70% helicity) of the protein in the capsules and its stability has been analyzed using cyclic voltammetry. The capsules have been characterized using zeta sizer and high resolution transmission electron microscopy (HRTEM). Surface concentration-surface pressure (Γ-π) isotherms of the films of the capsules spread at air/buffer interface following compression-expansion show destabilizing effect on cyt c. FTIR and CD spectra of these films skimmed from the surface show that the protein transitions gradually from its native helical to an anomalous beta sheet aggregated state. This results from a competition between stabilizing hydrated polar segments of the protein in the capsule and destabilizing nonspecific hydrophobic interactions arising at the air/buffer interface. This 2D model could further our understanding of the spatial and temporal roles of proteins in confined spaces and also in the design of new drug delivery vehicles using proteins.

  8. 2D-ordered dielectric sub-micron bowls on a metal surface: a useful hybrid plasmonic-photonic structure

    Science.gov (United States)

    Lan, Yue; Wang, Shiqiang; Yin, Xianpeng; Liang, Yun; Dong, Hao; Gao, Ning; Li, Jian; Wang, Hui; Li, Guangtao

    2016-07-01

    Recently, it has been demonstrated that the combination of periodic dielectric structures with metallic structures provides an efficient means to yield a synergetic optical response or functionality in the resultant hybrid plasmonic-photonic systems. In this work, a new hybrid plasmonic-photonic structure of 2D-ordered dielectric sub-micron bowls on a flat gold surface was proposed, prepared, and theoretically and experimentally characterized. This hybrid structure supports two types of modes: surface plasmon polaritons bound at the metallic surface and waveguided mode of light confined in the cavity of bowls. Optical responses of this hybrid structure as well as the spatial electric field distribution of each mode are found to be strongly dependent on the structural parameters of this system, and thus could be widely modified on demand. Importantly, compared to the widely studied hybrid systems, namely the flat metallic surface coated with a monolayer array of latex spheres, the waveguided mode with strong field enhancement appearing in the cavities of bowls is more facilely accessible and thus suitable for practical use. For demonstration, a 2D-ordered silica sub-micron bowl array deposited on a flat gold surface was fabricated and used as a regenerable platform for fluorescence enhancement by simply accommodating emitters in bowls. All the simulation and experiment results indicate that the 2D-ordered dielectric sub-micron bowls on a metal surface should be a useful hybrid plasmonic-photonic system with great potential for applications such as sensors or tunable emitting devices if appropriate periods and materials are employed.Recently, it has been demonstrated that the combination of periodic dielectric structures with metallic structures provides an efficient means to yield a synergetic optical response or functionality in the resultant hybrid plasmonic-photonic systems. In this work, a new hybrid plasmonic-photonic structure of 2D-ordered dielectric sub-micron

  9. 2D-ordered dielectric sub-micron bowls on a metal surface: a useful hybrid plasmonic-photonic structure.

    Science.gov (United States)

    Lan, Yue; Wang, Shiqiang; Yin, Xianpeng; Liang, Yun; Dong, Hao; Gao, Ning; Li, Jian; Wang, Hui; Li, Guangtao

    2016-07-21

    Recently, it has been demonstrated that the combination of periodic dielectric structures with metallic structures provides an efficient means to yield a synergetic optical response or functionality in the resultant hybrid plasmonic-photonic systems. In this work, a new hybrid plasmonic-photonic structure of 2D-ordered dielectric sub-micron bowls on a flat gold surface was proposed, prepared, and theoretically and experimentally characterized. This hybrid structure supports two types of modes: surface plasmon polaritons bound at the metallic surface and waveguided mode of light confined in the cavity of bowls. Optical responses of this hybrid structure as well as the spatial electric field distribution of each mode are found to be strongly dependent on the structural parameters of this system, and thus could be widely modified on demand. Importantly, compared to the widely studied hybrid systems, namely the flat metallic surface coated with a monolayer array of latex spheres, the waveguided mode with strong field enhancement appearing in the cavities of bowls is more facilely accessible and thus suitable for practical use. For demonstration, a 2D-ordered silica sub-micron bowl array deposited on a flat gold surface was fabricated and used as a regenerable platform for fluorescence enhancement by simply accommodating emitters in bowls. All the simulation and experiment results indicate that the 2D-ordered dielectric sub-micron bowls on a metal surface should be a useful hybrid plasmonic-photonic system with great potential for applications such as sensors or tunable emitting devices if appropriate periods and materials are employed.

  10. Prospects for Sub-Micron Solid State Nuclear Magnetic Resonance Imaging with Low-Temperature Dynamic Nuclear Polarization

    OpenAIRE

    Thurber, Kent R.; Tycko, Robert

    2010-01-01

    We evaluate the feasibility of 1H nuclear magnetic resonance (NMR) imaging with sub-micron voxel dimensions using a combination of low temperatures and dynamic nuclear polarization (DNP). Experiments are performed on nitroxide-doped glycerol/water at 9.4 T and temperatures below 40 K, using a 30 mW tunable microwave source for DNP. With DNP at 7 K, a 0.5 µl sample yields a 1H NMR signal-to-noise ratio of 770 in two scans with pulsed spin-lock detection and after 80 db signal attenuation. With...

  11. A Nordic project on high speed low power design in sub-micron CMOS technology for mobile phones

    DEFF Research Database (Denmark)

    Olesen, Ole

    This paper is a survey paper presenting the Nordic CONFRONT project and reporting some results from the group at CIE/DTU, Denmark. The objective of the project is to demonstrate the feasibility of sub-micron CMOS for the realisation of RF front-end circuits operating at frequencies in the 1...... circuit design is based on state-of-the-art CMOS technology (0.5µm and below) including circuits operating at 2GHz. CMOS technology is chosen, since a CMOS implementation is likely to be significantly cheaper than a bipolar or a BiCMOS solution, and it offers the possibility to integrate the predominantly...

  12. A simple and wide-range refractive index measuring approach by using a sub-micron grating

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chun-Wei; Wu, Chun-Che; Lin, Shih-Chieh [Department of Power Mechanical Engineering, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China)

    2015-04-13

    This paper presents the design and simulation results of a high-precision low-cost refractometer that demonstrates the main advantage of a wide measurement range (1 ≤ n ≤ 2). The proposed design is based on the diffractive properties of sub-micron gratings and Snell's Law. The precision and uncertainty factors of the proposed system were tested and analyzed, revealing that the proposed refractometer demonstrates a wide measurement range with sensitivity of 10{sup −4}.

  13. Free-standing millimetre-long Bi2Te3 sub-micron belts catalyzed by TiO2 nanoparticles.

    Science.gov (United States)

    Schönherr, Piet; Zhang, Fengyu; Kojda, Danny; Mitdank, Rüdiger; Albrecht, Martin; Fischer, Saskia F; Hesjedal, Thorsten

    2016-12-01

    Physical vapour deposition (PVD) is used to grow millimetre-long Bi2Te3 sub-micron belts catalysed by TiO2 nanoparticles. The catalytic efficiency of TiO2 nanoparticles for the nanostructure growth is compared with the catalyst-free growth employing scanning electron microscopy. The catalyst-coated and catalyst-free substrates are arranged side-by-side, and overgrown at the same time, to assure identical growth conditions in the PVD furnace. It is found that the catalyst enhances the yield of the belts. Very long belts were achieved with a growth rate of 28 nm/min. A ∼1-mm-long belt with a rectangular cross section was obtained after 8 h of growth. The thickness and width were determined by atomic force microscopy, and their ratio is ∼1:10. The chemical composition was determined to be stoichiometric Bi2Te3 using energy-dispersive X-ray spectroscopy. Temperature-dependent conductivity measurements show a characteristic increase of the conductivity at low temperatures. The room temperature conductivity of 0.20 × 10(5) S m (-1) indicates an excellent sample quality. PMID:27342602

  14. Dust diffusion and settling in the presence of collisions: Trapping (sub)micron grains in the midplane

    CERN Document Server

    Krijt, Sebastiaan

    2016-01-01

    In protoplanetary disks, the distribution and abundance of small (sub)micron grains are important for a range of physical and chemical processes. For example, they dominate the optical depth at short wavelengths and their surfaces are the sites of many important chemical reactions such as the formation of water. Based on their aerodynamical properties (i.e., their strong dynamical coupling with the surrounding gas) it is often assumed that these small grains are well-mixed with the gas. Our goal is to study the vertical (re)distribution of grains taking into account settling, turbulent diffusion, as well as collisions with other dust grains. Assuming a fragmentation-limited background dust population, we developed a Monte Carlo approach that follows single monomers as they move through a vertical column of gas and become incorporated in different aggregates as they undergo sticking and fragmenting collisions. We find that (sub)micron grains are not necessarily well-mixed vertically, but can become trapped in ...

  15. Biased reptation model with electroosmosis for DNA electrophoresis in microchannels with a sub-micron pillar array

    Science.gov (United States)

    Wang, Wentao; Chuen Chan, Yick; Lee, Yi-Kuen

    2011-08-01

    A novel biased reptation model with electroosmosis (BRE) is proposed for a long-chain DNA electrophoresis separation mechanism in microchannels with a sub-micron pillar array. The BRE model incorporates effective electroosmosis into the classical biased reptation model (BRM). Initial investigation of the BRM with additional electroosmosis flow was conducted. In order to validate the proposed BRE model, the apparent electrophoretic mobilities of different sizes of long-chain DNA, T4 DNA and lambda DNA at different electric fields were measured in a microfabricated electrophoresis chip with an embedded sub-micron pillar array. The current-monitoring method was used to measure the electroosmotic mobility in the microfabricated electrophoresis chip. The proposed BRE model shows much better agreement with the experimental results compared to the classical BRM and the semi-empirical results based on the biased reptation with fluctuation (BRF). The average standard error between our proposed BRE model and experimental data is 8.13% without any fitting parameters, while the errors are 343.01% for the BRM and 17.54% for the BRF with one fitting parameter, respectively.

  16. Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

    Energy Technology Data Exchange (ETDEWEB)

    Uzu, G. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: gaelle.uzu@ensat.fr; Sobanska, S. [LASIR UMR 8516, Universite des Sciences et Technologies de Lille, Batiment C5, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: Sophie.Sobanska@univ-lille1.fr; Aliouane, Y. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France); Pradere, P. [Chemical Metal Treatment Company, STCM, 30-32 chemin de Fondeyre, 31200 Toulouse (France)], E-mail: p.pradere@stc-metaux.com; Dumat, C. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: camille.dumat@ensat.fr

    2009-04-15

    Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 {+-} 20 mg Pb kg{sup -1}) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO{sub 4}, PbSO{sub 4}.PbO, {alpha}-PbO and Pb{sup 0}. Morphology investigations revealed that PM{sub 2.5} (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 {mu}m or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil-plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl{sub 2} extraction. - The soil-lettuce lead transfer from atmospheric industrial sub-micronic and micronic particles depends on particle size.

  17. Effects of Carbides on the Microstructural Evolution in Sub-micron Grain 9310 Steel During Isothermal Heat Treatment

    Science.gov (United States)

    Kozmel, Thomas; Tin, Sammy

    2015-07-01

    Recent interest in bulk ultra-fine-grained microstructures has given rise for the necessity to quantify their behavior during heat treatment should any subsequent thermal processing of the material be necessary after forming. The present study showed that the microstructure of 9310 steel forgings containing varying fractions of sub-micron grains retained some degree of stability after 4 hours of heat treatment between the temperatures of 522 K and 866 K (249 °C and 593 °C, respectively). The behavior of the microstructure during heat treatment was largely influenced by both the carbide volume fraction and distribution, which affected the level of Zener Drag present. This in effect controlled the type of growth behavior exhibited by the ferrite grains and the ability to retain the fine-grained structure.

  18. Resist evaluation for fabrication of diffractive optical elements (DOEs) with sub-micron resolution in a MEMS production line

    Science.gov (United States)

    Herbjørnrød, Aina; Schjølberg-Henriksen, Kari; Angelskår, Hallvard; Lacolle, Matthieu

    2009-12-01

    Diffractive optical elements (DOEs) represent small, lightweight and potentially low-cost alternatives to conventional optical components. We have evaluated photoresists and processes for fabrication of silicon micro-machined DOEs with a sub-micron pattern using an MA150 (Suss) proximity aligner. The resists HiPR 6512 (Fuji film), AZ ECI 3007 (AZ Electronics Materials), IX335 H (JSR Micro) and UVIII (Rohm and Haas) were all able to resolve the desired 0.8 µm pattern, but the wall angle obtained with IX335H was a superior 86°. Double development of the resists proved possible in a KOH-based developer but unfeasible in a TMAH-based developer. The final DOE device was successfully realized based on the optimized photolithography process.

  19. Resist evaluation for fabrication of diffractive optical elements (DOEs) with sub-micron resolution in a MEMS production line

    International Nuclear Information System (INIS)

    Diffractive optical elements (DOEs) represent small, lightweight and potentially low-cost alternatives to conventional optical components. We have evaluated photoresists and processes for fabrication of silicon micro-machined DOEs with a sub-micron pattern using an MA150 (Suss) proximity aligner. The resists HiPR 6512 (Fuji film), AZ ECI 3007 (AZ Electronics Materials), IX335 H (JSR Micro) and UVIII (Rohm and Haas) were all able to resolve the desired 0.8 µm pattern, but the wall angle obtained with IX335H was a superior 86°. Double development of the resists proved possible in a KOH-based developer but unfeasible in a TMAH-based developer. The final DOE device was successfully realized based on the optimized photolithography process

  20. Exploring the Role of Sub-micron Sized Dust Grains in the Atmospheres of Red L0 - L6 Dwarfs

    CERN Document Server

    Hiranaka, Kay; Douglas, Stephanie T; Marley, Mark S; Baldassare, Vivienne F

    2016-01-01

    We examine the hypothesis that the red near-infrared colors of some L dwarfs could be explained by a "dust haze" of small particles in their upper atmospheres. This dust haze would exist in conjunction with the clouds found in dwarfs with more typical colors. We developed a model which uses Mie theory and the Hansen particle size distributions to reproduce the extinction due to the proposed dust haze. We apply our method to 23 young L dwarfs and 23 red field L dwarfs. We constrain the properties of the dust haze including particle size distribution and column density using Markov-Chain Monte Carlo methods. We find that sub-micron range silicate grains reproduce the observed reddening. Current brown dwarf atmosphere models include large grain (1--100~$\\mu m$) dust clouds but not submicron dust grains. Our results provide a strong proof of concept and motivate a combination of large and small dust grains in brown dwarf atmosphere models.

  1. Dust Diffusion and Settling in the Presence of Collisions: Trapping (sub)micron Grains in the Midplane

    Science.gov (United States)

    Krijt, Sebastiaan; Ciesla, Fred J.

    2016-05-01

    In protoplanetary disks, the distribution and abundance of small (sub)micron grains are important for a range of physical and chemical processes. For example, they dominate the optical depth at short wavelengths and their surfaces are the sites of many important chemical reactions, such as the formation of water. Based on their aerodynamical properties (i.e., their strong dynamical coupling with the surrounding gas) it is often assumed that these small grains are well-mixed with the gas. Our goal is to study the vertical (re)distribution of grains taking into account settling, turbulent diffusion, and collisions with other dust grains. Assuming a fragmentation-limited background dust population, we developed a Monte Carlo approach that follows single monomers as they move through a vertical column of gas and become incorporated in different aggregates as they undergo sticking and fragmenting collisions. We find that (sub)micron grains are not necessarily well-mixed vertically, but can become trapped in a thin layer with a scale height that is significantly smaller than that of the gas. This collisional trapping occurs when the timescale for diffusion is comparable to or longer than the collision timescale in the midplane and its effect is strongest when the most massive particles in the size distribution show significant settling. Based on simulations and analytical considerations, we conclude that for typical dust-to-gas ratios and turbulence levels, the collisional trapping of small grains should be a relatively common phenomenon. The absence of trapping could then indicate a low dust-to-gas ratio, possibly because a large portion of the dust mass has been removed through radial drift or is locked up in planetesimals.

  2. Thermal conductivities of sub-micron Bi2Te3 films sputtered on anisotropic substrates

    Science.gov (United States)

    Yan, Dan; Wu, Ping; Zhang, Shiping; Pei, Yili; Yang, Fan; Wang, Li

    2016-07-01

    Approximately 450 nm thick Bi2Te3 films were deposited on flat Al2O3 substrate and nanochannel alumina (NCA) templates with different pore diameters through radio-frequency magnetron sputtering. The structure and morphology of Bi2Te3 films were investigated by x-ray diffraction and field-emission scanning electron microscopy. Moreover, the thermal conductivities of the films deposited on anisotropic substrates were evaluated by micro-Raman method combined with numerical simulation and optimization conducted by COMSOL Multiphysics. The thermal conductivities of Bi2Te3 films deposited on NCA templates with discontinuous Φ20 and Φ100 nm pores and flat Al2O3 substrate were 0.80, 0.99 and 1.54 Wm‑1 K‑1, respectively. The lower thermal conductivities of Bi2Te3 films deposited on NCA templates are attributed to much smaller grain size, bottom porous layers, and rougher surfaces through analysis.

  3. Ultrasonic array of thick film transducers for biological tissue characterization.

    Science.gov (United States)

    Gwirc, Sergio N; Negreira, Carlos A; Marino, Nestor R

    2010-01-01

    The initial motivation for this work was to accomplish an easy way to manufacture different geometries of ultrasonic transducers and arrays using a PZT powder, combined with a standard process to have repetitive series of them. The piezoelectric thick film was obtained using a PZT paste and applying it by screen printing on an alumina substrate. Then, the film was drying and sintered with a temperature-time profile determined by the paste characteristics. Each transducer is composed by three layers, one by PZT and two acting as electrodes. The active element of the paste is a PZT powder which is dispersed in a commercial vehicle to obtain rheological properties suitable for use the screen printing process. The connection between PZT particles is improved by adding a lead borosilicate frit glass that also helps to attach the film to the substrate due to the relatively low temperature of sintered that has been used in this process. The PZT film has low density that is generated by internal porosity, so its acoustic impedance is lower than for a bulk ceramic transducer and so is well adapted to testing human tissues. At the same time the thick film technology is well suited to make medium size transducers and also arrays performed with tiny ultrasonic transducers. PMID:21097177

  4. A method for sizing sub-micron particles using small angle diffraction of soft x-rays

    International Nuclear Information System (INIS)

    The purpose of this work is to develop a method of sizing sub-micron particles using small-angle soft x-ray diffraction. Solid poly-styrene spheres of known sizes were used as scattering samples, with C-Kα (44.8/angstrom/) and V-Lα (24.3/angstrom/) radiation from a conventional x-ray source. Two devices were used to diffract the x-rays. One collimates the radiation using a series of pinholes immediately preceding the sample, and directs the unfocussed radiation onto film placed far from the sample. The other utilizes radiation from a single pinhole above the source onto the sample and a spherical multilayer mirror in series, so that the radiation passes twice through the sample and is focused onto film immediately above the pinhole assembly to increase the effective sample area. Using the latter device, two types of diffraction patterns were obtained: a sharp, relatively small pattern from spheres which form a hexagonal lattice structure, and a diffuse, larger pattern from an unordered, or random, array of spheres. Both patterns are presented in this work, along with the calculations, based upon light scattering from an unordered and an ordered array of particles, of the scattering patterns. 9 refs., 32 figs., 2 tabs

  5. Prospects for Sub-Micron Solid State Nuclear Magnetic Resonance Imaging with Low-Temperature Dynamic Nuclear Polarization

    Science.gov (United States)

    Thurber, Kent R.; Tycko, Robert

    2010-01-01

    Summary We evaluate the feasibility of 1H nuclear magnetic resonance (NMR) imaging with sub-micron voxel dimensions using a combination of low temperatures and dynamic nuclear polarization (DNP). Experiments are performed on nitroxide-doped glycerol/water at 9.4 T and temperatures below 40 K, using a 30 mW tunable microwave source for DNP. With DNP at 7 K, a 0.5 µl sample yields a 1H NMR signal-to-noise ratio of 770 in two scans with pulsed spin-lock detection and after 80 db signal attenuation. With reasonable extrapolations, we infer that 1H NMR signals from 1 µm3 voxel volumes should be readily detectable, and voxels as small as 0.03 µm3 may eventually be detectable. Through homonuclear decoupling with a frequency-switched Lee-Goldburg spin echo technique, we obtain 830 Hz 1H NMR linewidths at low temperatures, implying that pulsed field gradients equal to 0.4 G/d or less would be required during spatial encoding dimensions of an imaging sequence, where d is the resolution in each dimension. PMID:20458431

  6. Exploitation of sub-micron cavitation nuclei to enhance ultrasound-mediated transdermal transport and penetration of vaccines.

    Science.gov (United States)

    Bhatnagar, Sunali; Kwan, James J; Shah, Apurva R; Coussios, Constantin-C; Carlisle, Robert C

    2016-09-28

    Inertial cavitation mediated by ultrasound has been previously shown to enable skin permeabilisation for transdermal drug and vaccine delivery, by sequentially applying the ultrasound then the therapeutic in liquid form on the skin surface. Using a novel hydrogel dosage form, we demonstrate that the use of sub-micron gas-stabilising polymeric nanoparticles (nanocups) to sustain and promote cavitation activity during simultaneous application of both drug and vaccine results in a significant enhancement of both the dose and penetration of a model vaccine, Ovalbumin (OVA), to depths of 500μm into porcine skin. The nanocups themselves exceeded the penetration depth of the vaccine (up to 700μm) due to their small size and capacity to 'self-propel'. In vivo murine studies indicated that nanocup-assisted ultrasound transdermal vaccination achieved significantly (p<0.05) higher delivery doses without visible skin damage compared to the use of a chemical penetration enhancer. Transdermal OVA doses of up to 1μg were achieved in a single 90-second treatment, which was sufficient to trigger an antigen-specific immune response. Furthermore, ultrasound-assisted vaccine delivery in the presence of nanocups demonstrated substantially higher specific anti-OVA IgG antibody levels compared to other transdermal methods. Further optimisation can lead to a viable, safe and non-invasive delivery platform for vaccines with potential use in a primary care setting or personalized self-vaccination at home. PMID:27417040

  7. Stable, Free-space Optical Trapping and Manipulation of Sub-micron Particles in an Integrated Microfluidic Chip

    Science.gov (United States)

    Kim, Jisu; Shin, Jung H.

    2016-01-01

    We demonstrate stable, free-space optical trapping and manipulation in an integrated microfluidic chip using counter-propagating beams. An inverted ridge-type waveguide made of SU8 is cut across by an open trench. The design of the waveguide provides low propagation losses and small divergence of the trapping beam upon emergence from the facet, and the trench designed to be deeper and wider than the optical mode enables full utilization of the optical power with an automatic alignment for counter-propagating beams in a trap volume away from all surfaces. After integration with polydimethylsiloxane (PDMS) microfluidic channel for particle delivery, 0.65 μm and 1 μm diameter polystyrene beads were trapped in free space in the trench, and manipulated to an arbitrary position between the waveguides with a resolution of < 100 nm. Comparison with numerical simulations confirm stable trapping of sub-micron particles, with a 10 kBT threshold power of less than 1 mW and a stiffness that can be 1 order of magnitude larger than that of comparable fiber-based trapping methods. PMID:27653191

  8. Multimodal imaging for the detection of sub-micron particles in the gas-exchange region of the mammalian lung

    Science.gov (United States)

    Haberthür, David; Semmler-Behnke, Manuela; Takenaka, Shinji; Kreyling, Wolfgang G.; Stampanoni, Marco; Tsuda, Akira; Schittny, Johannes C.

    2009-09-01

    The deposition sites of inhaled aerosols in the gas-exchange region of the lung represent one of the key parameters needed for the understanding of the interaction between these particles and lung tissue. In order to develop a method for three-dimensional imaging of sub-micron particles in lung tissue we applied gold particles (200 and 700 nm) to rat lungs by intratracheal instillation. The samples were scanned at TOMCAT, the beamline for TOmographic Microscopy and Coherent rAdiology experimenTs at the Swiss Light Source. The 200 nm particles were slightly below the detection capabilities of TOMCAT. Therefore, their localization was obtained only by electron microscopy. At a voxel size of 350 nm we observed single and clustered gold particles (700 nm) in alveoli, alveolar ducts, and small bronchioli. The locations of the gold particles were verified by transmission electron microscopical serial sections. We observed a very high correlation between these two imaging modalities. We conclude that a combination of x-ray tomographic microscopy and electron microscopy allows the full unrestricted 3D localization of particles smaller than the resolution of x-ray tomographic microscopy. We are planning to use this method for the verification of the simulation of particle deposition in the airway tree.

  9. Surface plasmon interference pattern on the surface of a silver-clad planar waveguide as a sub-micron lithography tool

    Science.gov (United States)

    Zhu, QiuXiang; Hu, CanDong; Wang, WenJie; He, Miao; Zhou, Jun; Zhao, LingZhi; Peng, ZhiXiang; Li, ShuTi; Zhu, Ning; Zhang, Yong

    2011-02-01

    A new sub-micron photolithography tool has been realized by utilizing the interference of surface plasmon waves (SPWs) on the near surface of a silver (Ag)-clad ultraviolet (UV) planar waveguide. A laser beam with a wavelength of 325 nm was incident into the waveguide core, and suffered a series of total internal reflections on the interfaces between the waveguide core and the cladding layers. The incident light and the reflected light induced two beams of SPWs traveling in contrary directions, which interfered with each other and formed a standing wave as a sub-micron photolithography tool. A near-field scanning optical microscope (NSOM) was employed to measure the intensity distribution of the stationary wave field of the near surface of the Ag layer of the waveguide, anastomosed with theoretical values acquired by use of finite difference time domain (FDTD) simulations. And with this sub-micron photolithography tool a SMG with a period of 79.3 nm, in good agreement with the theoretical value of 80.1 nm, was inscribed on the surface of a self-processing hybrid SiO2/ZrO2 solgel film for the first time.

  10. THREE-DIMENSIONAL OBSERVATIONS ON THICK BIOLOGICAL SPECIMENS BY HIGH VOLTAGE ELECTRON MICROSCOPY

    Directory of Open Access Journals (Sweden)

    Tetsuji Nagata

    2011-05-01

    Full Text Available Thick biological specimens prepared as whole mount cultured cells or thick sections from embedded tissues were stained with histochemical reactions, such as thiamine pyrophosphatase, glucose-6-phosphatase, cytochrome oxidase, acid phosphatase, DAB reactions and radioautography, to observe 3-D ultrastructures of cell organelles producing stereo-pairs by high voltage electron microscopy at accerelating voltages of 400-1000 kV. The organelles demonstrated were Golgi apparatus, endoplasmic reticulum, mitochondria, lysosomes, peroxisomes, pinocytotic vesicles and incorporations of radioactive compounds. As the results, those cell organelles were observed 3- dimensionally and the relative relationships between these organelles were demonstrated.

  11. Effect of epicuticular wax crystals on the localization of artificially deposited sub-micron carbon-based aerosols on needles of Cryptomeria japonica.

    Science.gov (United States)

    Nakaba, Satoshi; Yamane, Kenichi; Fukahori, Mie; Nugroho, Widyanto Dwi; Yamaguchi, Masahiro; Kuroda, Katsushi; Sano, Yuzou; Wuled Lenggoro, I; Izuta, Takeshi; Funada, Ryo

    2016-09-01

    Elucidation of the mechanism of adsorption of particles suspended in the gas-phase (aerosol) to the outer surfaces of leaves provides useful information for understanding the mechanisms of the effect of aerosol particles on the growth and physiological functions of trees. In the present study, we examined the localization of artificially deposited sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica, a typical Japanese coniferous tree species, by field-emission scanning electron microscopy. The clusters (aggregates) of carbon-based particles were deposited on the needle surface regions where epicuticular wax crystals were sparsely distributed. By contrast, no clusters of the particles were found on the needle surface regions with dense distribution of epicuticular wax crystals. Number of clusters of carbon-based particles per unit area showed statistically significant differences between regions with sparse epicuticular wax crystals and those with dense epicuticular wax crystals. These results suggest that epicuticular wax crystals affect distribution of carbon-based particles on needles. Therefore, densely distributed epicuticular wax crystals might prevent the deposition of sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica to retain the function of stomata.

  12. Microstructure and Strength of Laser Welds of Sub-micron Particulate-reinforced Aluminum Martix Composite Al2O3p/6061Al

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The microstructure of laser welds of sub-micron particulate-reinforced aluminum matrix composite Al2O3p/6061Al and the weldability of the material were studied.Experimental results indicated that because of the huge specific surface area of the reinforcement,the interfacial reaction between the matrix and the reinforcement was restrained intensively at elevated temperature and pulsed laser beam.The main factor affecting the weldability of the composite was the reinforcement segregation in the weld resulting from the push of the liquid/solid interface during the solidification of the molten pool.The laser pulse frequency directly affected the reinforcement segregation and the reinforcement distribution in the weld,so that the weldability of the composite could be improved by increasing the laser pulse frequency.On the bases of this,a satisfactory welded joint of sub-micron particulate-reinforced aluminum matrix composite Al2Op/6061Al was obtained by using appropriate welding parameters.

  13. Effects of Mg content on aging behavior of sub-micron Al2O3p/Al-Cu-Mg composites

    Institute of Scientific and Technical Information of China (English)

    JIANG Long-tao; ZHU De-zhi; CHEN Guo-qin; XIU Zi-yang; WU Gao-hui

    2006-01-01

    30%Al2O3p/Al-Cu-2.0Mg composite and Al2O3p/Al-Cu-2.5Mg composite with 0.3 μm-Al2O3 particles were fabricated.Age-hardening behaviors of two composites and the related matrix alloys were studied by means of Brinell-hardness measurement,DSC and TEM. The results show that the hardness of the composite is improved obviously because of the addition of sub-micron Al2O3 particles. But the hardness increment of Al2O3p/Al composite after aging is lower than that of the related matrix alloy.Moreover, the formation of GP region is suppressed by the addition of sub-micron Al2O3 particles, which broadens the exothermic peak of S' phase. The increment of Mg content has a different influence on accelerating the aging processes of aluminum alloys and the composites, and the hardness also increases.

  14. Hydrothermal Synthesis Au-Bi2Te3 Nanocomposite Thermoelectric Film with a Hierarchical Sub-Micron Antireflection Quasi-Periodic Structure

    Directory of Open Access Journals (Sweden)

    Junlong Tian

    2015-06-01

    Full Text Available In this work, Au-Bi2Te3 nanocomposite thermoelectric film with a hierarchical sub-micron antireflection quasi-periodic structure was synthesized via a low-temperature chemical route using Troides helena (Linnaeus forewing (T_FW as the biomimetic template. This method combines chemosynthesis with biomimetic techniques, without the requirement of expensive equipment and energy intensive processes. The microstructure and the morphology of the Au-Bi2Te3 nanocomposite thermoelectric film was analyzed by X-ray diffraction (XRD, field-emission scanning-electron microscopy (FESEM, and transmission electron microscopy (TEM. Coupled the plasmon resonances of the Au nanoparticles with the hierarchical sub-micron antireflection quasi-periodic structure, the Au-Bi2Te3 nanocomposite thermoelectric film possesses an effective infrared absorption and infrared photothermal conversion performance. Based on the finite difference time domain method and the Joule effect, the heat generation and the heat source density distribution of the Au-Bi2Te3 nanocomposite thermoelectric film were studied. The heterogeneity of heat source density distribution of the Au-Bi2Te3 nanocomposite thermoelectric film opens up a novel promising technique for generating thermoelectric power under illumination.

  15. Micro-PIXE analyses of frozen-hydrated semi-thick biological sections

    International Nuclear Information System (INIS)

    Cryo-micro-PIXE system and methodology of microanalysis of frozen-hydrated semi-thick biological sections is described. A commercially available cryotransfer system used in electron microscopy has been adapted for this purpose. The analyzed material was frozen by metal–mirror method and sections of 20–50 micron thickness were prepared. Micro-PIXE and simultaneous proton backscattering was performed using 3 MeV proton beam. Monitoring of water vapour composition during the proton bombardment showed good stability of the analyzed material. The results of repetitive analyses of standards prepared from gelatin–glycerol solution with added known concentrations of K, Ni, Cu, Zn were in good agreement with expected, calculated values. Mass losses and changes of elemental composition were monitored. Elemental maps obtained for frozen-hydrated semi-thick section of Ni hyperaccumulator Senecio coronatus showed excellent preservation of leaf morphology and the distribution of elements. Quantitative elemental mapping of frozen-hydrated specimens compared with subsequent analysis of the same areas after freeze-drying revealed similar distribution pattern in both cases. It is clear, however, that freeze-drying induces some distortion of cell morphology and specimen shrinkage

  16. Portable sample preparation and analysis system for micron and sub-micron particle characterization using light scattering and absorption spectroscopy

    Science.gov (United States)

    Stark, Peter C.; Zurek, Eduardo; Wheat, Jeffrey V.; Dunbar, John M.; Olivares, Jose A.; Garcia-Rubio, Luis H.; Ward, Michael D.

    2011-07-26

    There is provided a method and device for remote sampling, preparation and optical interrogation of a sample using light scattering and light absorption methods. The portable device is a filtration-based device that removes interfering background particle material from the sample matrix by segregating or filtering the chosen analyte from the sample solution or matrix while allowing the interfering background particles to be pumped out of the device. The segregated analyte is then suspended in a diluent for analysis. The device is capable of calculating an initial concentration of the analyte, as well as diluting the analyte such that reliable optical measurements can be made. Suitable analytes include cells, microorganisms, bioparticles, pathogens and diseases. Sample matrixes include biological fluids such as blood and urine, as well as environmental samples including waste water.

  17. Source apportionment of fine PM and sub-micron particle number concentrations at a regional background site in the western Mediterranean: a 2.5 yr study

    Science.gov (United States)

    Cusack, M.; Pérez, N.; Pey, J.; Alastuey, A.; Querol, X.

    2013-02-01

    The chemical composition and sources of ambient fine particulate matter (PM1) over a period of 2.5 yr for a regional background site in the western Mediterranean are presented in this work. Major components (such as SO12-, NO3-, NH4+, organic and elemental carbon) and trace elements were analysed and the emission sources affecting PM1 were determined using Positive Matrix Factorisation (PMF). Furthermore, sub-micron particle number concentrations and the sources of these particles are also presented. Sources of sub-micron particles were determined by Principal Component Analysis (PCA). The mean PM1 concentration for the measurement period was 8.9 μg m-3, with organic matter (OM) and sulphate comprising most of the mass (3.2 and 1.5 μg m-3). A clear seasonal variation was recorded with higher PM1 concentrations in summer (11.2 μg m-3) compared to winter (6.6 μg m-3). This summer increase was due to elevated levels of sulphate and OM. Six sources were identified by PMF: secondary organic aerosol, secondary nitrate, industrial, traffic + biomass burning, fuel oil combustion and secondary sulphate. The daily variations of these sources were also determined, whereby the typically anthropogenic sources displayed elevated concentrations during the week with reductions at weekends. Nitrate levels were elevated in winter and negligible in summer, whereas secondary sulphate levels underwent a contrasting seasonal evolution with highest concentrations in summer, similar to the fuel oil combustion source. The SOA source was influenced by episodes of sustained pollution as a result of anticyclonic conditions occurring during winter, giving rise to thermal inversions and the accumulation of pollutants in the mixing layer. Increased levels in summer were owing to higher biogenic emissions and regional recirculation of air masses. The industrial source decreased in August due to decreased emissions during the vacation period. Increases in the traffic + biomass burning source

  18. Determination of biological specimen optimal thickness for small-angle X-ray experiments by use polychromatic synchrotron radiation

    International Nuclear Information System (INIS)

    It is put forward the mode of evaluation of biological specimen optimal thickness for small-angle specimen thickness on various synchrotron radiation spectra are calculated. The curves allow to optimize an experiment by selecting either optimal specimen thickness for an available synchrotron radiation spectrum, or the disposition of the short-wave boundary for given specimen thickness (fibers, tissues and so on). The method gives the possibility apart from increasing both of the precision and reproducibility of X-ray experiments, either or both increase of the statistical precision upon given recording time of an X-ray pattern and decrease recording time upon retention of the same statistical precision. The 15-20 % deviation in the specimen thickness from that of optimal one is shown to lead to decrease in the scattering intensity less than 2 %. 15 refs.; 3 figs

  19. Source apportionment of fine PM and sub-micron particle number concentrations at a regional background site in the western Mediterranean: a 2.5 year study

    Science.gov (United States)

    Cusack, M.; Pérez, N.; Pey, J.; Alastuey, A.; Querol, X.

    2013-05-01

    The chemical composition and sources of ambient fine particulate matter (PM1) over a period of 2.5 years for a regional background site in the western Mediterranean are presented in this work. Furthermore, sub-micron particle number concentrations and the sources of these particles are also presented. The mean PM1 concentration for the measurement period was 8.9 μg m-3, with organic matter (OM) and sulphate comprising most of the mass (3.2 and 1.5 μg m-3 respectively). Six sources were identified in PM1 by Positive Matrix Factorisation (PMF): secondary organic aerosol, secondary nitrate, industrial, traffic + biomass burning, fuel oil combustion and secondary sulphate. Typically anthropogenic sources displayed elevated concentrations during the week with reductions at weekends. Nitrate levels were elevated in winter and negligible in summer, whereas secondary sulphate levels underwent a contrasting seasonal evolution with highest concentrations in summer, similar to the fuel oil combustion source. The SOA source was influenced by episodes of sustained pollution as a result of anticyclonic conditions occurring during winter, giving rise to thermal inversions and the accumulation of pollutants in the mixing layer. Increased levels in summer were owing to higher biogenic emissions and regional recirculation of air masses. The industrial source decreased in August due to decreased emissions during the vacation period. Increases in the traffic + biomass burning source were recorded in January, April and October, which were attributed to the occurrence of the aforementioned pollution episodes and local biomass burning emission sources, which include agriculture and domestic heating systems. Average particle number concentrations (N9-825 nm) from 5/11/2010 to 01/06/2011 and from 15/10/2011 to 18/12/2011 reached 3097 cm-3. Five emission sources of particle of sub-micron particles were determined by Principal Component Analysis (PCA); industrial + traffic + biomass

  20. A Fast, Versatile Nanoprobe for Complex Materials: The Sub-micron Resolution X-ray Spectroscopy Beamline at NSLS-II (491st Brookhaven Lecture)

    Energy Technology Data Exchange (ETDEWEB)

    Thieme, Juergen [BNL Photon Sciences Directorate

    2014-02-06

    Time is money and for scientists who need to collect data at research facilities like Brookhaven Lab’s National Synchrotron Light Source (NSLS), “beamtime” can be a precious commodity. While scanning a complex material with a specific technique and standard equipment today would take days to complete, researchers preparing to use brighter x-rays and the new sub-micron-resolution x-ray spectroscopy (SRX) beamline at the National Synchrotron Light Source II (NSLS-II) could scan the same sample in greater detail with just a few hours of beamtime. Talk about savings and new opportunities for researchers! Users will rely on these tools for locating trace elements in contaminated soils, developing processes for nanoparticles to deliver medical treatments, and much more. Dr. Thieme explains benefits for next-generation research with spectroscopy and more intense x-rays at NSLS-II. He discusses the instrumentation, features, and uses for the new SRX beamline, highlighting its speed, adjustability, and versatility for probing samples ranging in size from millimeters down to the nanoscale. He will talk about complementary beamlines being developed for additional capabilities at NSLS-II as well.

  1. The heterogeneous reaction of hydroxyl radicals with sub-micron squalane particles: a model system for understanding the oxidative aging of ambient aerosols

    Science.gov (United States)

    Smith, J. D.; Kroll, J. H.; Cappa, C. D.; Che, D. L.; Liu, C. L.; Ahmed, M.; Leone, S. R.; Worsnop, D. R.; Wilson, K. R.

    2009-05-01

    The heterogeneous reaction of OH radicals with sub-micron squalane particles, in the presence of O2, is used as a model system to explore the fundamental chemical mechanisms that control the oxidative aging of organic aerosols in the atmosphere. Detailed kinetic measurements combined with elemental mass spectrometric analysis reveal that the reaction proceeds sequentially by adding an average of one oxygenated functional group per reactive loss of squalane. The reactive uptake coefficient of OH with squalane particles is determined to be 0.3±0.07 at an average OH concentration of ~1×1010 molecules cm-3. Based on a comparison between the measured particle mass and model predictions it appears that significant volatilization of a reduced organic particle would be extremely slow in the real atmosphere. However, as the aerosols become more oxygenated, volatilization becomes a significant loss channel for organic material in the particle-phase. Together these results provide a chemical framework in which to understand how heterogeneous chemistry transforms the physiochemical properties of particle-phase organic matter in the troposphere.

  2. The heterogeneous reaction of hydroxyl radicals with sub-micron squalane particles: a model system for understanding the oxidative aging of ambient aerosols

    Directory of Open Access Journals (Sweden)

    J. D. Smith

    2009-02-01

    Full Text Available The heterogeneous reaction of OH radicals with sub-micron squalane particles, in the presence of O2, is used as a model system to explore the fundamental chemical mechanisms that control the oxidative aging of organic aerosols in the atmosphere. Detailed kinetic measurements combined with elemental mass spectrometric analysis reveal that the reaction proceeds sequentially by adding an average of one oxygenated functional group per reactive loss of squalane. The reactive uptake coefficient of OH with squalane particles is determined to be 0.3±0.07 at an average OH concentration of ~1×1010 molecules·cm−3. Based on a comparison between the measured particle mass and model predictions it appears that significant volatilization of a reduced organic particle would be extremely slow in the real atmosphere. However, as the aerosols become more oxygenated, volatilization becomes a significant loss channel for organic material in the particle phase. Together these results provide a chemical framework in which to understand how heterogeneous chemistry transforms the physiochemical properties of particle phase organic matter in the troposphere.

  3. The heterogeneous reaction of hydroxyl radicals with sub-micron squalane particles: a model system for understanding the oxidative aging of ambient aerosols

    Directory of Open Access Journals (Sweden)

    J. D. Smith

    2009-05-01

    Full Text Available The heterogeneous reaction of OH radicals with sub-micron squalane particles, in the presence of O2, is used as a model system to explore the fundamental chemical mechanisms that control the oxidative aging of organic aerosols in the atmosphere. Detailed kinetic measurements combined with elemental mass spectrometric analysis reveal that the reaction proceeds sequentially by adding an average of one oxygenated functional group per reactive loss of squalane. The reactive uptake coefficient of OH with squalane particles is determined to be 0.3±0.07 at an average OH concentration of ~1×1010 molecules cm−3. Based on a comparison between the measured particle mass and model predictions it appears that significant volatilization of a reduced organic particle would be extremely slow in the real atmosphere. However, as the aerosols become more oxygenated, volatilization becomes a significant loss channel for organic material in the particle-phase. Together these results provide a chemical framework in which to understand how heterogeneous chemistry transforms the physiochemical properties of particle-phase organic matter in the troposphere.

  4. Refractive lens based full-field x-ray imaging at 45-50 keV with sub-micron resolution

    Science.gov (United States)

    Shastri, S. D.; Kenesei, P.; Suter, R. M.

    2015-09-01

    Combining sub-micron spatial resolution full-field-imaging with the penetration property of high-energy x-rays (> 50 keV) offers numerous applications, such as the ability to observe cracks and voids associated with the onset of failure in engineering materials, complementing x-ray diffraction microscopy probes. Progress in the development of adding such an imaging capability at the Advanced Photon Source high-energy x-ray undulator beamline 1-ID is reported. An initially tested, long baseline configuration had 18-21× x-ray image magnification with compound refractive lenses (as objective) placed 1.8 m after the specimen, and a two-dimensional detector located at a 32-37 m additional distance, in a different experimental station. Later, a more compact set-up of 3.5× magnification with a ≍6 m sample-to-detector separation, fitting within a single end-station, was tested. Both set-ups demonstrated 500 nm level spatial resolutions at energies within the 45-50 keV range. Phase contrast artifacts are present, and are discussed in view of the goal of achieving tomography capability, at even higher resolution, in such an instrument with high x-ray energies.

  5. Image-Guided Ultrasound Characterization of Volatile Sub-Micron Phase-Shift Droplets in the 20-40 MHz Frequency Range.

    Science.gov (United States)

    Sheeran, Paul S; Daghighi, Yasaman; Yoo, Kimoon; Williams, Ross; Cherin, Emmanuel; Foster, F Stuart; Burns, Peter N

    2016-03-01

    Phase-shift perfluorocarbon droplets are designed to convert from the liquid to the gas state by the external application of acoustic or optical energy. Although droplet vaporization has been investigated extensively at ultrasonic frequencies between 1 and 10 MHz, few studies have characterized performance at the higher frequencies commonly used in small animal imaging. In this study, we use standard B-mode imaging sequences on a pre-clinical ultrasound platform to both image and activate sub-micron decafluorobutane droplet populations in vitro and in vivo at center frequencies in the range of 20-40 MHz. Results show that droplets remain stable against vaporization at low imaging pressures but are vaporized at peak negative pressures near 3.5 MPa at the three frequencies tested. This study also found that a small number of size outliers present in the distribution can greatly influence droplet performance. Removal of these outliers results in a more accurate assessment of the vaporization threshold and produces free-flowing microbubbles upon vaporization in the mouse kidney. PMID:26725168

  6. Hygroscopicity of Chemically Aged, sub-micron Squalane Particles: On the Role of Size and Composition towards the Hygroscopicity Parameter κ

    Science.gov (United States)

    Harmon, C. W.; Smith, J. D.; Che, D. L.; Leone, S. R.; Wilson, K. R.

    2010-12-01

    Measurements presented herein explore cloud condensation nuclei (CCN) activity of sub-micron squalane particles chemically aged by hydroxyl radicals as a function of size and OH exposure. As squalane particles are exposed to OH radicals, size-selected 100, 150, and 200 nm particles monotically decrease in size with increasing OH exposure. Concurrently, their CCN derived hygroscopicity parameter values, κ, increase with OH exposure until saturating at 0.165 in the 100 nm data set, 0.140 in the 150 nm data set, and reach a maximum value of 0.075 in the 200 nm data set at the highest level of OH exposure. The critical super-saturation relative humidity (RH) at which CCN activity is achieved decreases initially with increasing OH exposure and then increases with OH exposure, most notably for the 100 nm data set and weakly with the 150 nm data set. Chemically aged squalane particles from the 200 nm data set show a monotonic decrease in critical super-saturation RH with all values of increasing OH exposure between 0.1-2.5 × 10^13 s molec./cc. The measured O:C ratios of 160 nm chemically aged squalane particles, which were reported previously, are compared to κ values by the CCN derived relationship reported in literature: κ = 0.30*O:C and reasonable agreement is attained in the size-selected 150 nm data set. These values are also compared with the hygroscopic growth factor derived relationship in literature: κ = 0.49*(O:C -0.25) and reasonable agreement is attained at O:C > 0.35.

  7. Sub-micron indent induced plastic deformation in copper and irradiated steel; Deformation plastique induite par l'essai d'indentation submicronique, dans le cuivre et l'acier 316L irradie

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Ch

    1999-07-01

    In this work we aim to study the indent induced plastic deformation. For this purpose, we have developed a new approach, whereby the indentation curves provides the mechanical behaviour, while the deformation mechanisms are observed thanks to Transmission Electron Microscopy (TEM). In order to better understand how an indent induced dislocation microstructure forms, numerical modeling of the indentation process at the scale of discrete dislocations has been worked out as well. Validation of this modeling has been performed through direct comparison of the computed microstructures with TEM micrographs of actual indents in pure Cu (001]. Irradiation induced modifications of mechanical behaviour of ion irradiated 316L have been investigated, thanks to the mentioned approach. An important hardening effect was reported from indentation data (about 50%), on helium irradiated 316L steel. TEM observations of the damage zone clearly show that this behaviour is associated with the presence of He bubbles. TEM observations of the indent induced plastic zone also showed that the extent of the plastic zone is strongly correlated with hardness, that is to say: harder materials gets a smaller plastic zone. These results thus clearly established that the selected procedure can reveal any irradiation induced hardening in sub-micron thick ion irradiated layers. The behaviour of krypton irradiated 316L steel is somewhat more puzzling. In one hand indeed, a strong correlation between the defect cluster size and densities on the irradiation temperature is observed in the 350 deg. C - 600 deg. C range, thanks to TEM observations of the damage zone. On the other hand, irradiation induced hardening reported from indentation data is relatively small (about 10%) and shows no dependence upon the irradiation temperature (within the mentioned range). In addition, it has been shown that the reported hardening vanishes following appropriate post-irradiation annealing, although most of the TEM

  8. On the sub-micron aerosol size distribution in a coastal-rural site at El Arenosillo Station (SW-Spain

    Directory of Open Access Journals (Sweden)

    M. Sorribas

    2011-02-01

    Full Text Available This study is focused on the analysis of the sub-micron aerosol characteristics at rural and coastal environment in Southwestern Spain. Particle number size distributions were measured in the size range (14–673 nm using a Scanning Mobility Particle Sizer (SMPS, Model 3936-TSI, from 15 July 2004 to 31 July 2006 at El Arenosillo Station. Mean total concentration was 8660 cm−3 and mean concentrations for the nucleation, Aitken and accumulation modes particles were 2830 cm−3, 4110 cm−3 and 1720 cm−3, respectively. Mean geometric diameters of the four modes particles, which characterized the mean size distribution per month, were about 16 nm, 42 nm, 103 nm and 237 nm. Two kinds of episodes produced a maximum of the total concentration around noon: the new particle formation and the regional recirculation such as the sea-land breeze. Two types of nucleation events (called N$1 and N2 were observed. Events N1 were an example of the influence of regional sources and Events N2 showed the weight of local industries over the rural and coastal background levels. The 60% of nucleation events were related to NE and NW wind sectors (N1 and N2 respectively, a ΔT higher than 12 °C, a wind speed higher than 2.3 m s−1 and a total surface area for the accumulation mode particles below of 11 190 μ m2 cm−3. The influence of the sea-land breeze processes has been analyzed, observing increases of up to 50%, 110% and 90% of the particle concentration for the nucleation, Aitken and accumulation modes. Annual evolution of monthly averages allowed to conclude that the increase or decrease of 1 cm−3 of the concentration for nucleation mode particles was related to opposite trend of 0.5 cm−3 of the concentration for accumulation mode. This anti-correlation produced a weak seasonal

  9. On the sub-micron aerosol size distribution in a coastal-rural site at El Arenosillo Station (SW – Spain

    Directory of Open Access Journals (Sweden)

    M. Sorribas

    2011-11-01

    Full Text Available This study focuses on the analysis of the sub-micron aerosol characteristics at El Arenosillo Station, a rural and coastal environment in South-western Spain between 1 August 2004 and 31 July 2006 (594 days. The mean total concentration (NT was 8660 cm−3 and the mean concentrations in the nucleation (NNUC, Aitken (NAIT and accumulation (NACC particle size ranges were 2830 cm−3, 4110 cm−3 and 1720 cm−3, respectively. Median size distribution was characterised by a single-modal fit, with a geometric diameter, median number concentration and geometric standard deviation of 60 nm, 5390 cm−3 and 2.31, respectively. Characterisation of primary emissions, secondary particle formation, changes to meteorology and long-term transport has been necessary to understand the seasonal and annual variability of the total and modal particle concentration. Number concentrations exhibited a diurnal pattern with maximum concentrations around noon. This was governed by the concentrations of the nucleation and Aitken modes during the warm seasons and only by the nucleation mode during the cold seasons. Similar monthly mean total concentrations were observed throughout the year due to a clear inverse variation between the monthly mean NNUC and NACC. It was related to the impact of desert dust and continental air masses on the monthly mean particle levels. These air masses were associated with high values of NACC which suppressed the new particle formation (decreasing NNUC. Each day was classified according to a land breeze flow or a synoptic pattern influence. The median size distribution for desert dust and continental aerosol was dominated by the Aitken and accumulation modes, and marine air masses were dominated by the nucleation and Aitken modes. Particles

  10. Generalized Beer-Lambert model for near-infrared light propagation in thick biological tissues

    Science.gov (United States)

    Bhatt, Manish; Ayyalasomayajula, Kalyan R.; Yalavarthy, Phaneendra K.

    2016-07-01

    The attenuation of near-infrared (NIR) light intensity as it propagates in a turbid medium like biological tissue is described by modified the Beer-Lambert law (MBLL). The MBLL is generally used to quantify the changes in tissue chromophore concentrations for NIR spectroscopic data analysis. Even though MBLL is effective in terms of providing qualitative comparison, it suffers from its applicability across tissue types and tissue dimensions. In this work, we introduce Lambert-W function-based modeling for light propagation in biological tissues, which is a generalized version of the Beer-Lambert model. The proposed modeling provides parametrization of tissue properties, which includes two attenuation coefficients μ0 and η. We validated our model against the Monte Carlo simulation, which is the gold standard for modeling NIR light propagation in biological tissue. We included numerous human and animal tissues to validate the proposed empirical model, including an inhomogeneous adult human head model. The proposed model, which has a closed form (analytical), is first of its kind in providing accurate modeling of NIR light propagation in biological tissues.

  11. Estimation of PSD Shifts for High-Resolution Metrology of Thickness Micro-Changes with Possible Applications in Vessel Walls and Biological Membrane Characterization

    OpenAIRE

    Abelardo Ruiz; Héctor Calás; Tomás Gómez; Javier Brum; Carlos Negreira; Ivonne Bazán; Antonio Ramos; José Manuel de la Rosa

    2012-01-01

    Achieving accurate measurements of inflammation levels in tissues or thickness changes in biological membranes (e.g., amniotic sac, parietal pleura) and thin biological walls (e.g., blood vessels) from outside the human body, is a promising research line in the medical area. It would provide a technical basis to study the options for early diagnosis of some serious diseases such as hypertension, atherosclerosis or tuberculosis. Nevertheless, achieving the aim of non-invasive measurement of th...

  12. Sub-micron period grating structures in Ta2O5 thin oxide films patterned using UV laser post-exposure chemically assisted selective etching

    International Nuclear Information System (INIS)

    A high-resolution and low-damage method for patterning relief structures in thin Ta2O5 films by chemically assisted UV laser selective etching is presented. The method is based on the initial exposure of the Ta2O5 films to pulsed UV radiation (quadrupled Nd:YAG laser at 266 nm) at fluences below the ablation threshold, for the creation of volume damage in the exposed areas. Subsequent immersion of the exposed sample in a KOH solution results in selective etching of the UV-exposed areas, developing relief structures of high quality. Interferometric exposure was used for the patterning of such gratings with periods of the order of 500 nm in films with a thickness of 100 and 500 nm. The behaviour of the patterning process is studied using diffraction efficiency measurements and AFM scans. Diffraction efficiency increases by a factor of ∼63, compared to the undeveloped structure, were obtained for gratings exposed with 1000 pulses of 30 mJ/cm2 energy density, which were developed in a KOH solution. The etching method presented is being applied to the fabrication of gratings in optical waveguides

  13. Epicardial Fat Thickness as Cardiovascular Risk Factor and Therapeutic Target in Patients with Rheumatoid Arthritis Treated with Biological and Nonbiological Therapies

    Directory of Open Access Journals (Sweden)

    Marcos M. Lima-Martínez

    2014-01-01

    Full Text Available Rheumatoid arthritis (RA is a chronic inflammatory disease associated with high cardiovascular morbidity and mortality. Epicardial adipose tissue (EAT thickness may act as a therapeutic target during treatments with drugs modulating the adipose tissue. We evaluate EAT thickness in RA patients treated with biological and nonbiological disease-modifying antirheumatic drugs (DMARDs. A cross-sectional study was conducted with a cohort of 34 female RA patients and 16 controls matched for age and body mass index (BMI. Plasma glucose, basal insulin, plasma lipids, and high-sensitivity C-reactive protein (hs-CRP were assessed. EAT thickness and left ventricular mass (LVM were measured by echocardiography. No significant differences in waist circumference (WC, blood pressure, fasting blood glucose, basal insulin, and lipid parameters were found between the groups. The control group showed lower concentrations (P=0.033 of hs-CRP and LVM (P=0.0001 than those of the two RA groups. Patients treated with TNF-α inhibitors showed significantly lower EAT thickness than those treated with nonbiological DMARDs (8.56 ± 1.90 mm versus 9.71 ± 1.45 mm; P=0.04. Women with no RA revealed reduced EAT thickness (5.39 ± 1.52 mm as compared to all RA patients (P=0.001. Results suggest that RA patients have greater EAT thickness than controls regardless of BMI and WC.

  14. Estimation of PSD Shifts for High-Resolution Metrology of Thickness Micro-Changes with Possible Applications in Vessel Walls and Biological Membrane Characterization

    Science.gov (United States)

    Ramos, Antonio; Bazán, Ivonne; Negreira, Carlos; Brum, Javier; Gómez, Tomás; Calás, Héctor; Ruiz, Abelardo; de la Rosa, José Manuel

    2012-01-01

    Achieving accurate measurements of inflammation levels in tissues or thickness changes in biological membranes (e.g., amniotic sac, parietal pleura) and thin biological walls (e.g., blood vessels) from outside the human body, is a promising research line in the medical area. It would provide a technical basis to study the options for early diagnosis of some serious diseases such as hypertension, atherosclerosis or tuberculosis. Nevertheless, achieving the aim of non-invasive measurement of those scarcely-accessible parameters on patient internal tissues, currently presents many difficulties. The use of high-frequency ultrasonic transducer systems appears to offer a possible solution. Previous studies using conventional ultrasonic imaging have shown this, but the spatial resolution was not sufficient so as to permit a thickness evaluation with clinical significance, which requires an accuracy of a few microns. In this paper a broadband ultrasonic technique, that was recently developed by the authors to address other non-invasive medical detection problems (by integrating a piezoelectric transducer into a spectral measuring system), is extended to our new objective; the aim is its application to the thickness measurement of sub-millimeter membranes or layers made of materials similar to some biological tissues (phantoms). The modeling and design rules of such a transducer system are described, and various methods of estimating overtones location in the power spectral density (PSD) are quantitatively assessed with transducer signals acquired using piezoelectric systems and also generated from a multi-echo model. Their effects on the potential resolution of the proposed thickness measuring tool, and their capability to provide accuracies around the micron are studied in detail. Comparisons are made with typical tools for extracting spatial parameters in laminar samples from echo-waveforms acquired with ultrasonic transducers. Results of this advanced measurement

  15. Estimation of PSD Shifts for High-Resolution Metrology of Thickness Micro-Changes with Possible Applications in Vessel Walls and Biological Membrane Characterization

    Directory of Open Access Journals (Sweden)

    Abelardo Ruiz

    2012-11-01

    Full Text Available Achieving accurate measurements of inflammation levels in tissues or thickness changes in biological membranes (e.g., amniotic sac, parietal pleura and thin biological walls (e.g., blood vessels from outside the human body, is a promising research line in the medical area. It would provide a technical basis to study the options for early diagnosis of some serious diseases such as hypertension, atherosclerosis or tuberculosis. Nevertheless, achieving the aim of non-invasive measurement of those scarcely-accessible parameters on patient internal tissues, currently presents many difficulties. The use of high-frequency ultrasonic transducer systems appears to offer a possible solution. Previous studies using conventional ultrasonic imaging have shown this, but the spatial resolution was not sufficient so as to permit a thickness evaluation with clinical significance, which requires an accuracy of a few microns. In this paper a broadband ultrasonic technique, that was recently developed by the authors to address other non-invasive medical detection problems (by integrating a piezoelectric transducer into a spectral measuring system, is extended to our new objective; the aim is its application to the thickness measurement of sub-millimeter membranes or layers made of materials similar to some biological tissues (phantoms. The modeling and design rules of such a transducer system are described, and various methods of estimating overtones location in the power spectral density (PSD are quantitatively assessed with transducer signals acquired using piezoelectric systems and also generated from a multi-echo model. Their effects on the potential resolution of the proposed thickness measuring tool, and their capability to provide accuracies around the micron are studied in detail. Comparisons are made with typical tools for extracting spatial parameters in laminar samples from echo-waveforms acquired with ultrasonic transducers. Results of this advanced

  16. Monte Carlo electron-trajectory simulations in bright-field and dark-field STEM: Implications for tomography of thick biological sections

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, A.A.; Hohmann-Marriott, M.F.; Zhang, G. [Laboratory of Bioengineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bldg. 13, Rm. 3N17, 13 South Drive, Bethesda, MD 20892-5766 (United States); Leapman, R.D. [Laboratory of Bioengineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bldg. 13, Rm. 3N17, 13 South Drive, Bethesda, MD 20892-5766 (United States)], E-mail: leapmanr@mail.nih.gov

    2009-02-15

    A Monte Carlo electron-trajectory calculation has been implemented to assess the optimal detector configuration for scanning transmission electron microscopy (STEM) tomography of thick biological sections. By modeling specimens containing 2 and 3 at% osmium in a carbon matrix, it was found that for 1-{mu}m-thick samples the bright-field (BF) and annular dark-field (ADF) signals give similar contrast and signal-to-noise ratio provided the ADF inner angle and BF outer angle are chosen optimally. Spatial resolution in STEM imaging of thick sections is compromised by multiple elastic scattering which results in a spread of scattering angles and thus a spread in lateral distances of the electrons leaving the bottom surface. However, the simulations reveal that a large fraction of these multiply scattered electrons are excluded from the BF detector, which results in higher spatial resolution in BF than in high-angle ADF images for objects situated towards the bottom of the sample. The calculations imply that STEM electron tomography of thick sections should be performed using a BF rather than an ADF detector. This advantage was verified by recording simultaneous BF and high-angle ADF STEM tomographic tilt series from a stained 600-nm-thick section of C. elegans. It was found that loss of spatial resolution occurred markedly at the bottom surface of the specimen in the ADF STEM but significantly less in the BF STEM tomographic reconstruction. Our results indicate that it might be feasible to use BF STEM tomography to determine the 3D structure of whole eukaryotic microorganisms prepared by freeze-substitution, embedding, and sectioning.

  17. Scanning transmission ion microscopy mass measurements for quantitative trace element analysis within biological samples and validation using atomic force microscopy thickness measurements

    Science.gov (United States)

    Devès, Guillaume; Cohen-Bouhacina, Touria; Ortega, Richard

    2004-10-01

    We used the nuclear microprobe techniques, micro-PIXE (particle-induced X-ray emission), micro-RBS (Rutherford backscattering spectrometry) and scanning transmission ion microscopy (STIM) in order to perform the characterization of trace element content and spatial distribution within biological samples (dehydrated cultured cells, tissues). The normalization of PIXE results was usually expressed in terms of sample dry mass as determined by micro-RBS recorded simultaneously to micro-PIXE. However, the main limit of RBS mass measurement is the sample mass loss occurring during irradiation and which could be up to 30% of the initial sample mass. We present here a new methodology for PIXE normalization and quantitative analysis of trace element within biological samples based on dry mass measurement performed by mean of STIM. The validation of STIM cell mass measurements was obtained in comparison with AFM sample thickness measurements. Results indicated the reliability of STIM mass measurement performed on biological samples and suggested that STIM should be performed for PIXE normalization. Further information deriving from direct confrontation of AFM and STIM analysis could as well be obtained, like in situ measurements of cell specific gravity within cells compartment (nucleolus and cytoplasm).

  18. Scanning transmission ion microscopy mass measurements for quantitative trace element analysis within biological samples and validation using atomic force microscopy thickness measurements

    Energy Technology Data Exchange (ETDEWEB)

    Deves, Guillaume [Laboratoire de chimie nucleaire analytique et bioenvironnementale, UMR 5084, CNRS-Universite de Bordeaux 1, BP 120 Chemin du solarium, F33175 Gradignan cedex (France)]. E-mail: deves@cenbg.in2p3.fr; Cohen-Bouhacina, Touria [Centre de Physique Moleculaire Optique et Hertzienne, Universite de Bordeaux 1, 351, cours de la Liberation, F33405 Talence cedex (France); Ortega, Richard [Laboratoire de chimie nucleaire analytique et bioenvironnementale, UMR 5084, CNRS-Universite de Bordeaux 1, BP 120 Chemin du solarium, F33175 Gradignan cedex (France)

    2004-10-08

    We used the nuclear microprobe techniques, micro-PIXE (particle-induced X-ray emission), micro-RBS (Rutherford backscattering spectrometry) and scanning transmission ion microscopy (STIM) in order to perform the characterization of trace element content and spatial distribution within biological samples (dehydrated cultured cells, tissues). The normalization of PIXE results was usually expressed in terms of sample dry mass as determined by micro-RBS recorded simultaneously to micro-PIXE. However, the main limit of RBS mass measurement is the sample mass loss occurring during irradiation and which could be up to 30% of the initial sample mass. We present here a new methodology for PIXE normalization and quantitative analysis of trace element within biological samples based on dry mass measurement performed by mean of STIM. The validation of STIM cell mass measurements was obtained in comparison with AFM sample thickness measurements. Results indicated the reliability of STIM mass measurement performed on biological samples and suggested that STIM should be performed for PIXE normalization. Further information deriving from direct confrontation of AFM and STIM analysis could as well be obtained, like in situ measurements of cell specific gravity within cells compartment (nucleolus and cytoplasm)

  19. An ultra-thin Schottky diode as a transmission particle detector for biological microbeams

    International Nuclear Information System (INIS)

    We fabricated ultrathin metal-semiconductor Schottky diodes for use as transmission particle detectors in the biological microbeam at Columbia University's Radiological Research Accelerator Facility (RARAF). The RARAF microbeam can deliver a precise dose of ionizing radiation in cell nuclei with sub-micron precision. To ensure an accurate delivery of charged particles, the facility currently uses a commercial charged-particle detector placed after the sample. We present here a transmission detector that will be placed between the particle accelerator and the biological specimen, allowing the irradiation of samples that would otherwise block radiation from reaching a detector behind the sample. Four detectors were fabricated with co-planar gold and aluminum electrodes thermally evaporated onto etched n-type crystalline silicon substrates, with device thicknesses ranging from 8.5 μm - 13.5 μm. We show coincident detections and pulse-height distributions of charged particles in both the transmission detector and the commercial detector above it. Detections are demonstrated at a range of operating conditions, including incoming particle type, count rate, and beam location on the detectors. The 13.5 μm detector is shown to work best to detect 2.7 MeV protons (H+), and the 8.5 μm detector is shown to work best to detect 5.4 MeV alpha particles (4He++). The development of a transmission detector enables a range of new experiments to take place at RARAF on radiation-stopping samples such as thick tissues, targets that need immersion microscopy, and integrated microfluidic devices for handling larger quantities of cells and small organisms.

  20. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  1. Metrology of sub-micron structured polymer surfaces

    DEFF Research Database (Denmark)

    Quagliotti, Danilo; Tosello, Guido; Salaga, J.;

    surface replication of the tool insert component when moulding the polymer melt [1]. This aspect is particularly critical when dealing with increasingly small dimensional scales in micro- and nano-structured surfaces [2, 3].In this context, a metrological investigation of polymer replicated surfaces using...... metal masters with different types of finish has been carried out.Four types of surface finish were considered: a) Diamond buff polishing. b) Grit paper polishing. c) Stone polishing. d) Dry blast polishing (see Fig. 1). Both master and replicated surfaces were measured using a laser scanning confocal...

  2. Sub-Micron Grinding of a Food Product

    NARCIS (Netherlands)

    Hennart, S.L.A.

    2011-01-01

    This thesis describes how the activity of a preservative product used in food coatings can be optimized. This project is partly sponsored by the European Marie Curie Framework projects as part of the BioPowders research training network. DSM Food Specialties hosts and co finances this project. The r

  3. Physics of sub-micron cosmic dust particles

    Science.gov (United States)

    Roy, N. L.

    1974-01-01

    Laboratory tests with simulated micrometeoroids to measure the heat transfer coefficient are discussed. Equations for ablation path length for electrically accelerated micrometeoroids entering a gas target are developed which yield guidelines for the laboratory measurement of the heat transfer coefficient. Test results are presented for lanthanum hexaboride (LaB sub 6) microparticles in air, argon, and oxygen targets. The tests indicate the heat transfer coefficient has a value of approximately 0.9 at 30 km/sec, and that it increases to approximately unity at 50 km/sec and above. Test results extend to over 100 km/sec. Results are also given for two types of small particle detectors. A solid state capacitor type detector was tested from 0.61 km/sec to 50 km/sec. An impact ionization type detector was tested from 1.0 to 150 km/sec using LaB sub 6 microparticles.

  4. Dynamics of vortex matter in YBCO sub-micron bridges

    International Nuclear Information System (INIS)

    Highlights: • Superconducting properties of YBCO nanowires in the width range ξ

  5. Noise in sub-micron CMOS image sensors

    OpenAIRE

    Wang, X.

    2008-01-01

    CMOS image sensors are devices that convert illumination signals (light intensity) into electronic signals. The goal of this thesis has been to analyze dominate noise sources in CMOS imagers and to improve the image quality by reducing the noise generated in the CMOS image sensor pixels.

  6. Noise estimation for deep sub-micron integrated circuits

    Institute of Scientific and Technical Information of China (English)

    陈彬; 杨华中; 汪惠

    2001-01-01

    Noise analysis and avoidance are an increasingly critical step in the design of deep submicron (DSM) integrated circuits (Ics). The crosstalk between neighboring interconnects gradually becomes the main noise sources in DSM Ics. We introduce an efficient and accurate noise-evaluation method for capacitively coupled nets of Ics. The method holds for a victim net with arbitrary number of aggressive nets under ramp input excitation. For common RC nets extracted by electronic design automation (EDA) tools, the deviation between our method and HSPICE is under 10%.

  7. Virtual Impactor for Sub-micron Aerosol Particles

    Science.gov (United States)

    Bolshakov, A. A.; Strawa, A. W.; Hallar, A. G.

    2005-12-01

    The objective of a virtual impactor is to separate out the larger particles in a flow from the smaller particles in such a way that both sizes of particles are available for sampling. A jet of particle-laden air is accelerated toward a collection probe so that a small gap exists between the acceleration nozzle and the probe. A vacuum is applied to deflect a major portion of the airstream away form the collection probe. Particles larger than a certain size have sufficient momentum so that they cross the deflected streamlines and enter the collection probe, whereas smaller particles follow the deflected streamlines. The result is that the collection probe will contain a higher concentration of larger particles than is in the initial airstream. Typically, virtual impactors are high-flow devices used to separate out particles greater than several microns in diameter. We have developed a special virtual impactor to concentrate aerosol particles of diameters between 0.5 to 1 micron for the purpose of calibrating the optical cavity ring-down instrument [1]. No similar virtual impactors are commercially available. In our design, we have exploited considerations described earlier [2-4]. Performance of our virtual impactor was evaluated in an experimental set-up using TSI 3076 nebulizer and TSI 3936 scanning mobility particle size spectrometer. Under experimental conditions optimized for the best performance of the virtual impactor, we were able to concentrate the 700-nm polystyrene particles no less than 15-fold. However, under experimental conditions optimized for calibrating our cavity ring-down instrument, a concentration factor attainable was from 4 to 5. During calibration experiments, maximum realized particle number densities were 190, 300 and 1600 cm-3 for the 900-nm, 700-nm and 500-nm spheres, respectively. This paper discusses the design of the impactor and laboratory studies verifying its performance. References: 1. A.W. Strawa, R. Castaneda, T. Owano, D.S. Baer, B.A. Paldus, J. Atm. Ocean. Technol., 20, 454-465 (2003). 2. V.A. Marple, K.L. Rubow, B.A. Olson, Aerosol Sci. Technol., 22, 140-150 (1995). 3. B.T. Chen, H.C. Yeh, Y.S. Cheng, J. Aerosol Sci., 16, 343-354 (1985). 4. V.A. Marple, C.M. Chien, Environ. Sci. Technol., 14, 976-985 (1980).

  8. 4D (x-y-z-t) imaging of thick biological samples by means of Two-Photon inverted Selective Plane Illumination Microscopy (2PE-iSPIM)

    Science.gov (United States)

    Lavagnino, Zeno; Sancataldo, Giuseppe; D’Amora, Marta; Follert, Philipp; de Pietri Tonelli, Davide; Diaspro, Alberto; Cella Zanacchi, Francesca

    2016-04-01

    In the last decade light sheet fluorescence microscopy techniques, such as selective plane illumination microscopy (SPIM), has become a well established method for developmental biology. However, conventional SPIM architectures hardly permit imaging of certain tissues since the common sample mounting procedure, based on gel embedding, could interfere with the sample morphology. In this work we propose an inverted selective plane microscopy system (iSPIM), based on non-linear excitation, suitable for 3D tissue imaging. First, the iSPIM architecture provides flexibility on the sample mounting, getting rid of the gel-based mounting typical of conventional SPIM, permitting 3D imaging of hippocampal slices from mouse brain. Moreover, all the advantages brought by two photon excitation (2PE) in terms of reduction of scattering effects and contrast improvement are exploited, demonstrating an improved image quality and contrast compared to single photon excitation. The system proposed represents an optimal platform for tissue imaging and it smooths the way to the applicability of light sheet microscopy to a wider range of samples including those that have to be mounted on non-transparent surfaces.

  9. Uncovering three-dimensional gradients in fibrillar orientation in an impact-resistant biological armour

    Science.gov (United States)

    Zhang, Y.; Paris, O.; Terrill, N. J.; Gupta, H. S.

    2016-05-01

    The complex hierarchical structure in biological and synthetic fibrous nanocomposites entails considerable difficulties in the interpretation of the crystallographic texture from diffraction data. Here, we present a novel reconstruction method to obtain the 3D distribution of fibres in such systems. An analytical expression is derived for the diffraction intensity from fibres, explaining the azimuthal intensity distribution in terms of the angles of the three dimensional fibre orientation distributions. The telson of stomatopod (mantis shrimp) serves as an example of natural biological armour whose high impact resistance property is believed to arise from the hierarchical organization of alpha chitin nanofibrils into fibres and twisted plywood (Bouligand) structures at the sub-micron and micron scale. Synchrotron microfocus scanning X-ray diffraction data on stomatopod telson were used as a test case to map the 3D fibre orientation across the entire tissue section. The method is applicable to a range of biological and biomimetic structures with graded 3D fibre texture at the sub-micron and micron length scales.

  10. Corneal thickness in glaucoma.

    Science.gov (United States)

    De Cevallos, E; Dohlman, C H; Reinhart, W J

    1976-02-01

    The central corneal stromal thickness of patients with open angle glaucoma, secondary glaucoma (the majority aphakic), or a history of unilateral acute angle closure glaucoma were measured and compared with the stromal thickness of a group of normal patients. In open angle glaucoma, there was a small but significant increase in the average stromal thickness. This thickness increase was, in all likelihood, due to an abnormal function of the endothelium in this disease since the level of the intraocular pressure did not seem to be a factor. There was no correlation between stromal thickness and duration of the glaucoma or type of anti-glaucomatous medication. Most cases of secondary glaucome, controlled medically or not, had markedly increased corneal thickness, again, most likely, due to endothelial damage rather than to level of intraocular pressure. After an angle closure attack, permanent damage to the cornea was found to be rare. PMID:1247273

  11. Thick film hydrogen sensor

    Science.gov (United States)

    Hoffheins, Barbara S.; Lauf, Robert J.

    1995-01-01

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

  12. Education and "Thick" Epistemology

    Science.gov (United States)

    Kotzee, Ben

    2011-01-01

    In this essay Ben Kotzee addresses the implications of Bernard Williams's distinction between "thick" and "thin" concepts in ethics for epistemology and for education. Kotzee holds that, as in the case of ethics, one may distinguish between "thick" and "thin" concepts of epistemology and, further, that this distinction points to the importance of…

  13. Importance of Corneal Thickness

    Science.gov (United States)

    ... News About Us Donate In This Section The Importance of Corneal Thickness email Send this article to ... is important because it can mask an accurate reading of eye pressure, causing doctors to treat you ...

  14. Ocean Sediment Thickness Contours

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean sediment thickness contours in 200 meter intervals for water depths ranging from 0 - 18,000 meters. These contours were derived from a global sediment...

  15. Mechanical Properties of Additively Manufactured Thick Honeycombs

    Directory of Open Access Journals (Sweden)

    Reza Hedayati

    2016-07-01

    Full Text Available Honeycombs resemble the structure of a number of natural and biological materials such as cancellous bone, wood, and cork. Thick honeycomb could be also used for energy absorption applications. Moreover, studying the mechanical behavior of honeycombs under in-plane loading could help understanding the mechanical behavior of more complex 3D tessellated structures such as porous biomaterials. In this paper, we study the mechanical behavior of thick honeycombs made using additive manufacturing techniques that allow for fabrication of honeycombs with arbitrary and precisely controlled thickness. Thick honeycombs with different wall thicknesses were produced from polylactic acid (PLA using fused deposition modelling, i.e., an additive manufacturing technique. The samples were mechanically tested in-plane under compression to determine their mechanical properties. We also obtained exact analytical solutions for the stiffness matrix of thick hexagonal honeycombs using both Euler-Bernoulli and Timoshenko beam theories. The stiffness matrix was then used to derive analytical relationships that describe the elastic modulus, yield stress, and Poisson’s ratio of thick honeycombs. Finite element models were also built for computational analysis of the mechanical behavior of thick honeycombs under compression. The mechanical properties obtained using our analytical relationships were compared with experimental observations and computational results as well as with analytical solutions available in the literature. It was found that the analytical solutions presented here are in good agreement with experimental and computational results even for very thick honeycombs, whereas the analytical solutions available in the literature show a large deviation from experimental observation, computational results, and our analytical solutions.

  16. How thick is the lithosphere?

    Science.gov (United States)

    Kanamori, H; Press, F

    1970-04-25

    A rapid decrease in shear velocity in the suboceanic mantle is used to infer the thickness of the lithosphere. It is proposed that new and highly precise group velocity data constrain the solutions and imply a thickness near 70 km.

  17. Ultrasonic Inspection Of Thick Sections

    Science.gov (United States)

    Friant, C. L.; Djordjevic, B. B.; O'Keefe, C. V.; Ferrell, W.; Klutz, T.

    1993-01-01

    Ultrasonics used to inspect large, relatively thick vessels for hidden defects. Report based on experiments in through-the-thickness transmission of ultrasonic waves in both steel and filament-wound composite cases of solid-fuel rocket motors.

  18. Radioactive thickness gauge (1962)

    International Nuclear Information System (INIS)

    The author describes a thickness gauge in which the scintillating crystal detector alternately 'sees' a radioactive source through the material which is to be measured and then a control source of the same material; the radiations are separated in time by an absorbing valve whose sections are alternately full and hollow. The currents corresponding to the two sources are separated beyond the photomultiplier tube by a detector synchronized with the rotation of the valve. The quotient of these two currents is then obtained with a standard recording potentiometer. It is found that the average value of the response which is in the form G = f(I1/I2) is not affected by decay of the radioactive sources, and that it is little influenced by variations of high tension, temperature, or properties of the air in the source detector interval. The performance of the gauge is given. (author)

  19. Optimum thickness of Mossbauer absorber

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    If recoilless fraction fa is available, the optimum absorber thickness dopt can be calculated by maximizing the signal to noise ratio or Q factor. In this work,an approach presented is to get experimental Qexp as a function of the thickness, and then fitting Qexp by its theoretical expression gives fa value. At last the dopt value is deduced from a maximum on the fitted curve. In such a way, thicknesses of six specimens with quadrupole or magnetic hyperfine splitting were optimized.

  20. Static and dynamic through thickness lamina properties of thick laminates

    NARCIS (Netherlands)

    Lahuerta, F.; Nijssen, R.P.L.; Van der Meer, F.P.; Sluys, L.J.

    2015-01-01

    Thick laminates are increasingly present in large composites structures such as wind turbine blades. Different factors are suspected to be involved in the decreased static and dynamic performance of thick laminates. These include the effect of self-heating, the scaling effect, and the manufacturing

  1. Analysis and optimization of current sensing circuit for deep sub-micron SRAM

    Institute of Scientific and Technical Information of China (English)

    Wang Yiqi; Zhao Fazhan; Liu Mengxin; Lü Yinxue; Zhao Bohua; Han Zhensheng

    2011-01-01

    A quantitative yield analysis of a traditional current sensing circuit considering the random dopant fluctuation effect is presented.It investigates the impact of transistor size,falling time of control signal CS and threshold voltage of critical transistors on failure probability of current sensing circuit.On this basis,we present a final optimization to improve the reliability of current sense amplifier.Under 90 nm process,simulation shows that failure probability of current sensing circuit can be reduced by 80% after optimization compared with the normal situation and the delay time only increases marginally.

  2. Deep sub-micron stud-via technology of superconductor VLSI circuits

    International Nuclear Information System (INIS)

    A fabrication process has been developed for fully planarized Nb-based superconducting interlayer connections (vias) with minimum size down to 250 nm for superconductor very large scale integrated (VLSI) circuits with 8 and 10 superconducting layers on 200-mm wafers. Instead of etched contact holes in the interlayer dielectric it employs etched and planarized Nb pillars (studs) as connectors between adjacent wiring layers. Detailed results are presented for one version of the process that utilizes Nb/Al/Nb trilayers for each wiring layer instead of single Nb wiring layers. Nb studs are etched in the top layer of the trilayer to provide vertical connections between the wires etched in the bottom layer of the trilayer and the next wiring layer that is also deposited as a Nb/Al/Nb trilayer. This technology makes possible a dramatic increase in the density of superconducting digital circuits by reducing the area of interconnects with respect to presently utilized etched contact holes between superconducting layers and by enabling the use of stacked vias. Results on the fabrication and size dependence of electric properties of Nb studs with dimensions near the resolution limit of 248-nm photolithography are presented in the normal and superconducting states. Superconducting critical current density in the fabricated stud-vias is about 0.3 A μm−2 and approaches the depairing current density of Nb films. (paper)

  3. Deep sub-micron stud-via technology for superconductor VLSI circuits

    International Nuclear Information System (INIS)

    A fabrication process has been developed for fully planarized Nb-based superconducting inter-layer connections (vias) with minimum size down to 250 nm for superconductor very large scale integrated (VLSI) circuits with 8 and 10 superconducting layers on 200-mm wafers. Instead of single Nb wiring layers, it utilizes Nb/Al/Nb trilayers for each wiring layer to form Nb pillars (studs) providing vertical connections between the wires etched in the bottom layer of the trilayer and the next wiring layer that is also deposited as a Nb/Al/Nb trilayer. This technology makes possible a dramatic increase in the density of superconducting digital circuits by reducing the area of interconnects with respect to presently utilized etched contact holes between superconducting layers and by enabling the use of stacked vias. Results on the fabrication and size dependence of electric properties of Nb studs with dimensions near the resolution limit of 248-nm photolithography are presented. Superconducting critical current density in the fabricated stud-vias is about 0.3 A/μm2 and approaches the depairing current density of Nb films.

  4. Performance and Analysis of Ultra Deep Sub Micron Technology Using Complementary Metal Oxide Semiconductor Inverter

    Directory of Open Access Journals (Sweden)

    Shikha Goswami

    2014-12-01

    Full Text Available CMOS technology had attained remarkable to progress and advances thus this progress had been achieved by certain downsizing of the MOSFETs. The dimension of the MOSFETs were scaled upon by factor which has historically found to be 0.7 in very large scal e integration technology, power and delay analysis have become crucial design concern. tn this paper we emp hasize the comparative study of delay, average powe r and leakage power of CMOS inverter in Ultra Deep Su bmicron Technology range. This study shows variation of following as follows by delay to UDSM technology and also for average power and leakage power by diminishing to certain technology. The sim ulation results are taken for 45nm in Ultra Deep Submicron Technology range with the help of Cadence Tool and also analyzing the effect of load capacitance, transistor width and supply voltage on average power and delay of CMOS inverter of 45nm technology. Therefore the analysis has done with th e aim to observe about the certain variation in del ay and power with variation in transistor width in UDS M CMOS inverter and also had variation in load capacitance and supply voltage had been studied

  5. Deviation from threshold model in ultrafast laser ablation of graphene at sub-micron scale

    Energy Technology Data Exchange (ETDEWEB)

    Gil-Villalba, A.; Xie, C.; Salut, R.; Furfaro, L.; Giust, R.; Jacquot, M.; Lacourt, P. A.; Dudley, J. M.; Courvoisier, F., E-mail: francois.courvoisier@femto-st.fr [Institut FEMTO-ST, UMR 6174 CNRS, Universite de Bourgogne Franche-Comte, 25030 Besançon Cedex (France)

    2015-08-10

    We investigate a method to measure ultrafast laser ablation threshold with respect to spot size. We use structured complex beams to generate a pattern of craters in CVD graphene with a single laser pulse. A direct comparison between beam profile and SEM characterization allows us to determine the dependence of ablation probability on spot-size, for crater diameters ranging between 700 nm and 2.5 μm. We report a drastic decrease of ablation probability when the crater diameter is below 1 μm which we interpret in terms of free-carrier diffusion.

  6. The Fate of Sub-micron Circumplanetary Dust Grains II: Multipolar Fields

    CERN Document Server

    Jontof-Hutter, Daniel

    2012-01-01

    We study the radial and vertical stability of dust grains launched with all charge-to-mass ratios at arbitrary distances from rotating planets with complex magnetic fields. We show that the aligned dipole magnetic field model analyzed by Jontof-Hutter and Hamilton (2012) is an excellent approximation in most cases, but that fundamentally new physics arises with the inclusion of non-axisymmetric magnetic field terms. In particular, large numbers of distant negatively-charged dust grains, stable in a magnetic dipole, can be driven to escape by a more complex field. We trace the origin of the instability to overlapping Lorentz resonances which are extremely powerful when the gravitational and electromagnetic forces on a dust grain are comparable. These resonances enable a dust grain to tap the spin energy of the planet to power its escape. We also explore the relatively minor influence of different launch speeds and the far more important effects of variable grain charge. Only the latter are capable of significa...

  7. Strain sensing with sub-micron sized Al-AlOx-Al tunnel junctions

    OpenAIRE

    Koppinen, P. J.; Lievonen, J. T.; Ahlskog, M.; Maasilta, I. J.

    2009-01-01

    We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlOx barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an AFM tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed, up to a value 37. This facilitates local static strain variation measurements down to ~10^{-7}.

  8. Preparation of chitosan-TPP sub-micron particles: Critical evaluation and derived recommendations.

    Science.gov (United States)

    Rázga, Filip; Vnuková, Dominika; Némethová, Veronika; Mazancová, Petra; Lacík, Igor

    2016-10-20

    The controlled preparation of chitosan particles is far from being trivial due to a considerable number of experimental parameters. For chitosan-tripolyphosphate (TPP) particles we evaluate the impact of chemical (type of chitosan, concentration, chitosan to TPP ratio, pH, ionic strength) and process factors (dialysis, stirring rate, rate of TPP addition, temperature, needle diameter) on the size and colloidal stability. The particles were prepared at pH=6.0 at which chitosan adopts the coiled conformation that is discussed as the dominant factor in controlling the stoichiometry of crosslinking reaction shifted towards TPP. These conditions result in identical particle size around 400nm and zeta potential around 22mV. The colloidal stability evaluated 24 hours after preparation depends on the amount of TPP during crosslinking. Under the same conditions, the colloidal stability up to 1 month is demonstrated. Several recommendations are provided to increase the control over formation of chitosan-TPP particles. PMID:27474593

  9. Nanoreplicated positive and inverted sub-micron polymer pyramids array for surface enhanced Raman spectroscopy (SERS)

    CERN Document Server

    Xu, Zhida

    2014-01-01

    We demonstrate gold coated polymer surface enhanced Raman scattering (SERS) substrates with a pair of complementary structures--positive and inverted pyramids array structures fabricated by multiple-step molding and replication process. The uniform SERS enhancement factors over the entire device surfaces were measured as 7.2 X 10^4 for positive pyramids substrate while 1.6 X 10^6 for inverted pyramids substrate with Rhodamine 6G as the target analyte. Based on the optical reflection measurement and FDTD simulation result, the enhancement factor difference is attributed to plasmon resonance matching and to SERS "hot spots ". With this simple, fast and versatile complementary molding process, we can produce polymer SERS substrates with extremely low cost, high throughput and high repeatability.

  10. InAlAs/InGaAs/InP sub-micron HEMTs grown by CBE

    Science.gov (United States)

    Munns, G. O.; Sherwin, M. E.; Brock, T.; Haddad, G. I.; Kwon, Y.; Ng, G. I.; Pavlidis, D.

    1992-05-01

    The paper describes the growth of InGaAs/InAlAs and InP/InAlAs high-electron-mobility transistors (HEMTs), using InAlAs grown by chemical beam epitaxy (CBE) with trimethyl amine alane (TMAA). The InAlAs bulk layers showed background carrier concentrations of 2 x 10 exp 14/cu cm, with 15 K photoluminescence FWHM of only 18.5 meV. Planar doped InAlAs/InGaAS HEMTs grown by CBE showed f(t) values of 150 GHz and f(max) values of 160 GHz.

  11. Suspension Plasma Spraying of Sub-micron Silicon Carbide Composite Coatings

    Science.gov (United States)

    Mubarok, F.; Espallargas, N.

    2015-06-01

    Thermal spraying of silicon carbide (SiC) material is a challenging task since SiC tends to decompose during atmospheric spraying process. The addition of metal or ceramic binders is necessary to facilitate the bonding of SiC particles, allowing SiC composite coating to be deposited. In the conventional procedures, the binders are added through mechanical mixing of powder constituents, making it difficult to achieve homogeneous distribution. In the new procedure proposed in this work, the binder is delivered as a nano-film of the surface of the individual SiC particles through co-precipitation treatment. Suspension plasma spray (SPS) coating technique has been used with the aim at avoiding the decomposition of SiC typically expected with atmospheric techniques, such as atmospheric plasma spray. The deposited SiC coatings by SPS showed identical SiC phase peak as identified in the suspension feedstock, indicating that the nano-film binder was able to protect SiC particles from decomposition. Further analysis by XPS revealed that SiC particles underwent some minor oxidation. Unfortunately, all the SiC coatings exhibited poor mechanical performance due to low cohesive strength, high porosity, and powdery structure making the coatings vulnerable to grain pull-out. This was due to the absence of sintering process during the spraying process contributing to the low performance of SiC SPS coatings.

  12. Sub-micron resolution rf cavity beam position monitor system at the SACLA XFEL facility

    Energy Technology Data Exchange (ETDEWEB)

    Maesaka, H., E-mail: maesaka@spring8.or.jp [RIKEN SPring-8 Center, Sayo, Hyogo (Japan); Ego, H. [RIKEN SPring-8 Center, Sayo, Hyogo (Japan); Inoue, S. [SPring-8 Service Co. Ltd., Tatsuno, Hyogo (Japan); Matsubara, S. [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo (Japan); Ohshima, T.; Shintake, T.; Otake, Y. [RIKEN SPring-8 Center, Sayo, Hyogo (Japan)

    2012-12-22

    We have developed and constructed a C-band (4.760 GHz) rf cavity beam position monitor (RF-BPM) system for the XFEL facility at SPring-8, SACLA. The demanded position resolution of the RF-BPM is less than 1{mu}m, because an electron beam and x-rays must be overlapped within 4{mu}m precision in the undulator section for sufficient FEL interaction between the electrons and x-rays. In total, 57 RF-BPMs, including IQ demodulators and high-speed waveform digitizers for signal processing, were produced and installed into SACLA. We evaluated the position resolutions of 20 RF-BPMs in the undulator section by using a 7 GeV electron beam having a 0.1 nC bunch charge. The position resolution was measured to be less than 0.6{mu}m, which was sufficient for the XFEL lasing in the wavelength region of 0.1 nm, or shorter.

  13. Size effects in the deformation of sub-micron Au columns

    OpenAIRE

    Volkert, Cynthia Ann; Lilleodden, Erica T

    2006-01-01

    Abstract Uniaxial compression tests have been performed on single crystal Au columns ranging in diameter from 180 nm to 8 im. The columns were machined into the surface of a large-grained Au sheet using a focused ion beam microscope and then mechanically tested using a nanoindenter outfitted with a flat diamond punch. Images of the compressed columns show that deformation occurs by localized shear on the slip systems with the largest resolved shear stresses. After an elastic loadin...

  14. Sub-micron scale patterning of fluorescent silver nanoclusters using low-power laser

    OpenAIRE

    Puskal Kunwar; Jukka Hassinen; Godofredo Bautista; Ras, Robin H. A.; Juha Toivonen

    2016-01-01

    Noble metal nanoclusters are ultrasmall nanomaterials with tunable properties and huge application potential; however, retaining their enhanced functionality is difficult as they readily lose their properties without stabilization. Here, we demonstrate a facile synthesis of highly photostable silver nanoclusters in a polymer thin film using visible light photoreduction. Furthermore, the different stages of the nanocluster formation are investigated in detail using absorption and fluorescence ...

  15. Deep sub-micron stud-via technology of superconductor VLSI circuits

    Science.gov (United States)

    Tolpygo, Sergey K.; Bolkhovsky, V.; Weir, T.; Johnson, L. M.; Oliver, W. D.; Gouker, M. A.

    2014-02-01

    A fabrication process has been developed for fully planarized Nb-based superconducting interlayer connections (vias) with minimum size down to 250 nm for superconductor very large scale integrated (VLSI) circuits with 8 and 10 superconducting layers on 200-mm wafers. Instead of etched contact holes in the interlayer dielectric it employs etched and planarized Nb pillars (studs) as connectors between adjacent wiring layers. Detailed results are presented for one version of the process that utilizes Nb/Al/Nb trilayers for each wiring layer instead of single Nb wiring layers. Nb studs are etched in the top layer of the trilayer to provide vertical connections between the wires etched in the bottom layer of the trilayer and the next wiring layer that is also deposited as a Nb/Al/Nb trilayer. This technology makes possible a dramatic increase in the density of superconducting digital circuits by reducing the area of interconnects with respect to presently utilized etched contact holes between superconducting layers and by enabling the use of stacked vias. Results on the fabrication and size dependence of electric properties of Nb studs with dimensions near the resolution limit of 248-nm photolithography are presented in the normal and superconducting states. Superconducting critical current density in the fabricated stud-vias is about 0.3 A μm-2 and approaches the depairing current density of Nb films.

  16. Deep sub-micron stud-via technology for superconductor VLSI circuits

    Science.gov (United States)

    Tolpygo, Sergey K.; Bolkhovsky, V.; Weir, T.; Johnson, L. M.; Oliver, W. D.; Gouker, M. A.

    2014-05-01

    A fabrication process has been developed for fully planarized Nb-based superconducting inter-layer connections (vias) with minimum size down to 250 nm for superconductor very large scale integrated (VLSI) circuits with 8 and 10 superconducting layers on 200-mm wafers. Instead of single Nb wiring layers, it utilizes Nb/Al/Nb trilayers for each wiring layer to form Nb pillars (studs) providing vertical connections between the wires etched in the bottom layer of the trilayer and the next wiring layer that is also deposited as a Nb/Al/Nb trilayer. This technology makes possible a dramatic increase in the density of superconducting digital circuits by reducing the area of interconnects with respect to presently utilized etched contact holes between superconducting layers and by enabling the use of stacked vias. Results on the fabrication and size dependence of electric properties of Nb studs with dimensions near the resolution limit of 248-nm photolithography are presented. Superconducting critical current density in the fabricated stud-vias is about 0.3 A/μm2 and approaches the depairing current density of Nb films.

  17. Sub-micron imaging of buried integrated circuit structures using scanning confocal electron microscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, S. P.; Levine, Z.; Zaluzec, N. J.; Materials Science Division; Northern Arizona Univ.; NIST

    2002-09-09

    Two-dimensional images of model integrated circuit components were collected using the technique of scanning confocal electron microscopy. For structures embedded about 5 {mu}m below the surface of a silicon oxide dielectric, a lateral resolution of 76{+-}9 nm was measured. Elemental mapping via x-ray emission spectrometry is demonstrated. A parallax analysis of images taken for various tilt angles to the electron beam allowed determination of the spacing between two wiring planes. The results show that scanning confocal electron microscopy is capable of probing buried structures at resolutions that will be necessary for the inspection of next-generation integrated circuit technology.

  18. A percolation study of RTS noise in deep sub-micron MOSFET by Monte Carlo simulation

    Institute of Scientific and Technical Information of China (English)

    Ma Zhong-Fa; Zhuang Yi-Qi; Du Lei; Wei Shan

    2005-01-01

    Based on percolation theory and random telegraph signal (RTS) noise generation mechanism, a numerical model for RTS in deep submicron metal-oxide-semiconductor field-effect transistor (MOSFET) was presented, with which the dependence of τc/τe (where τc=capture time, τe=emission period ) on energy levels and trap depth with respect to the interface of traps can be simulated. Compared with experimental results, the simulated ones showed a good qualitative agreement.

  19. Dynamics of Dissolved Organic Matter and Microbes in Seawater through Sub-Micron Particle Size Analyses

    Digital Repository Service at National Institute of Oceanography (India)

    Goes, J.I.; Balch, W.M.; Vaughn, J.M.; Gomes, H.R.

    . Filtered seawater as a carrier solution is pumped by two precision pumps through the channel at right angles to each other. The flow along the long axis of the channel (called the channel flow) is laminar and has a parabolic profile with faster flow... molecules of DOC through photodegradation making DOM more accessible to heterotrophs (Tranvik and Bertilsson, 2001). An increase in viral particles and the lack of bacterial debris flowing viral infection of bacteria corroborates optical measurements...

  20. Laser forming for sub-micron adjustment: with application to optical fiber assembly

    NARCIS (Netherlands)

    Folkersma, Klaas Gerrit Pieter

    2015-01-01

    Laser forming is a method to deform a material by controlled local laser heating. In combination with a dedicated actuator topology, those deformations can be used for high precision alignment of components. This thesis applies this method to the alignment of optical fibers with respect to the waveg

  1. Sub-micron scale patterning of fluorescent silver nanoclusters using low-power laser

    Science.gov (United States)

    Kunwar, Puskal; Hassinen, Jukka; Bautista, Godofredo; Ras, Robin H. A.; Toivonen, Juha

    2016-04-01

    Noble metal nanoclusters are ultrasmall nanomaterials with tunable properties and huge application potential; however, retaining their enhanced functionality is difficult as they readily lose their properties without stabilization. Here, we demonstrate a facile synthesis of highly photostable silver nanoclusters in a polymer thin film using visible light photoreduction. Furthermore, the different stages of the nanocluster formation are investigated in detail using absorption and fluorescence spectroscopy, fluorescence microscopy, and atomic force microscopy. A cost-effective fabrication of photostable micron-sized fluorescent silver nanocluster barcode is demonstrated in silver-impregnated polymer films using a low-power continuous-wave laser diode. It is shown that a laser power of as low as 0.75 mW is enough to write fluorescent structures, corresponding to the specifications of a commercially available laser pointer. The as-formed nanocluster-containing microstructures can be useful in direct labeling applications such as authenticity marking and fluorescent labeling.

  2. Analysis and Test Development for Parasitic Fails in Deep Sub-Micron Memory Devices

    NARCIS (Netherlands)

    Irobi, I.S.

    2011-01-01

    Emerging technology trends are gravitating towards extremely high levels of integration at the package and chip levels, and use of deeply scaled technology in nanometer, approaching 10nm CMOS. Challenges will arise due to the ability to design complex systems such as robots that encompass sensors, t

  3. Peripapillary choroidal thickness in childhood.

    Science.gov (United States)

    Read, Scott A; Alonso-Caneiro, David; Vincent, Stephen J; Collins, Michael J

    2015-06-01

    Changes in the thickness of the invivo peripapillary choroid have been documented in a range of ocular conditions in adults; however, choroidal thickness in the peripapillary region of children has not been examined in detail. This study therefore aimed to investigate the thickness of the peripapillary choroid and the overlying retinal nerve fibre layer (RNFL) in a population of normal children with a range of refractive errors. Ninety-three children (37 myopes and 56 non-myopes) aged between 11 and 16 years, had measurements of peripapillary choroidal and RNFL thickness derived from enhanced depth imaging optical coherence tomography images (EDI-OCT, Heidelberg Spectralis). The average thickness was determined in a series of five 0.25 mm width concentric annuli (each divided into 8 equal sized 45° sectors) centred on the optic nerve head boundary, accounting for individual ocular magnification factors and the disc-fovea angle. Significant variations in peripapillary choroidal thickness were found to occur with both annulus location (p annuli of the nasal and temporal sectors respectively (p < 0.001). RNFL thickness also varied significantly with annulus location and sector (p < 0.001), and showed differences in thickness distribution associated with refractive error. This study establishes the normal variations in the thickness of the peripapillary choroid with radial distance and azimuthal angle from the optic nerve head boundary. A significant thinning of the peripapillary choroid associated with myopia in childhood was also observed in both nasal and temporal regions. The changes in peripapillary RNFL and choroidal thickness associated with refractive error are consistent with a redistribution of these tissues occurring with myopic axial elongation in childhood. PMID:25749004

  4. Huge thick conglomerate movement induced by full thick longwall mining huge thick coal seam

    Institute of Scientific and Technical Information of China (English)

    Ma Liqiang; Qiu Xiaoxiang; Dong Tao; Zhang Jixiong; Huang Yanli

    2012-01-01

    A discrete elemental method was used to study the thickness of conglomerate layer in a full thick seam mining activities under the influence of the law,pointing out the thickness of the conglomerate at different seam mining,and during the destruction and instability of existing state of laws.At 21141 thick seam mining,the face toward the direction of separation between the thick layer of conglomerate rock and the next bit after reaching its maximum capacity due to pull from the bottom of the plastic zone,formed a stratified and hierarchical down collapse.The shape of caving area is a "triangular block",the length of the plastic zone and face advancement from the linear fit between the height of the plastic zone and the advancing face is a quadratic function of distance,while the top layer of thick gravel layer is the overall bending subsidence trend.Tilting the direction of the face,a thick gob of collapsed conglomerate layer is formed in the coal gob entity on both sides of the thick conglomerate at the top of the overall fracture morphology performance,thus forming a mutual extrusion of articulated block structure.The instability,separation and balance of the thick conglomerate layer in the hinged block stope stress leads to abnormal occurrence of rock burst induced by face as the major factor in the accident.This research reveals the form of stress distribution in the destroyed layer of the thick conglomerate rock,analyzes the stope law of coupling for the pressure burst behavior law for the mining work face,and the choice of preventive measures to provide a theoretical basis and implementation.

  5. Edge-on thick discs

    Science.gov (United States)

    Kasparova, A.; Katkov, I.; Chilingarian, I.; Silchenko, O.; Moiseev, A.; Borisov, S.

    2016-06-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on early-type disc galaxies located in different environments: NGC4111 in a dense group, NGC4710 in the Virgo cluster, and NGC5422 in a sparse group. We see intermediate age (4 ‑ 5 Gyr) metal rich ([Fe/H] ~ ‑0.2 ‑ 0.0 dex) stellar populations in NGC4111 and NGC4710. On the other hand, NGC5422 does not harbour young stars, its only disc is thick and old (10 Gyr) and its α-element abundance suggests a long formation epoch implying its formation at high redshift. Our results prove the diversity of thick disc formation scenarios.

  6. Rapid changes in LLBL thickness

    OpenAIRE

    Hapgood, Mike; Lockwood, Mike

    1995-01-01

    We employ data from two spacecraft, at the dawn flank of the magnetopause, to investigate fluctuations in the thickness of the low-latitude boundary layer (LLBL). We show the LLBL is considerably thinner shortly after the detection of a flux transfer event than it was during the event. These data are shown to be consistent with the theory of transient increases in the open LLBL thickness caused by a pulse of enhanced reconnection at the magnetopause.

  7. Critical Thickness in Dewetting Films

    OpenAIRE

    Du, B; Z. Yang; Tsui, O. K. C.

    2001-01-01

    We study dewetting of thin polymer films with built-in topographical fluctuations produced by rubbing the film surface with a rayon cloth. By varying the density of imposed surface defects, we unambiguously distinguish spinodal dewetting, which dominates in liquid films thinner than a characteristic thickness = 13.3 nm, from heterogeneous nucleation in the thicker films. Invariance of this characteristic thickness upon more than a decade change in the defect density makes kinetic effect an un...

  8. Biological Threats

    Science.gov (United States)

    ... Workplace Plans School Emergency Plans Main Content Biological Threats Biological agents are organisms or toxins that can ... for Disease Control and Prevention . Before a Biological Threat Unlike an explosion, a biological attack may or ...

  9. Climatology of ionospheric slab thickness

    Directory of Open Access Journals (Sweden)

    B. Jayachandran

    2004-01-01

    Full Text Available The ionospheric slab thickness τ defined as a ratio of the total electron content (TEC to the F-region peak electron density (NmF2 has been analysed during the solar maximum (1981 and minimum (1985 phases of an intense, the 21st, solar cycle. Hourly values of TEC and NmF2 collected at Hawaii (low-latitude, Boulder (mid-latitude and Goosebay (high-latitude are used in the study. Climatology of the slab thickness is described by the diurnal, seasonal, solar and magnetic activity variations of τ for the different latitude zones. It is found that, for magnetically quiet days of solar maximum, increased ionization of NmF2 and TEC during the daytime is accompanied by an increased thickness of the ionosphere compared to the night-time for non-auroral latitudes. However, the reverse is found to be true during the solar minimum compensating TEC against a weak night-time ionization of NmF2. For the high-latitude the night-time slab thickness is higher compared to the daytime for both the solar phases. Ratios of daily peak to minimum values of slab thickness vary from 1.3 to 3.75 with the peaks of τ often observed at pre-sunrise and post-sunset hours. The average night-to-day ratios of τ vary from 0.68 to 2.23. The day-to-day variability of τ, expressed in percentage standard deviation, varies from 10% by day (equinox, high-latitude to 67% by night (summer, mid-latitude during solar minimum and from 10% by day (winter and equinox, mid-latitude to 56% by night (equinox, high-latitude during solar maximum. A comprehensive review of slab thickness related literature is given in the paper.

    Key words. Ionospheric physics

  10. MACULAR THICKNESS CHANGE AFTER PHACOEMULSIFICATION

    Directory of Open Access Journals (Sweden)

    Sirisha

    2016-03-01

    Full Text Available Phacoemulsification for Cataract is the standard surgery in recent times with very good results and least complications. Macular area is the most important part of the Retina, which is very sensitive for any type of Insults on the Eye. It takes different durations for the Macula to return to normal condition after Phacoemulsification. Our aim of this study is to evaluate the macular thickness changes occurring after Phacoemulsification in post-operative period by using OCT in measuring the Retinal thickness.

  11. Three-dimensional visualisation of soft biological structures by X-ray computed micro-tomography.

    Science.gov (United States)

    Shearer, Tom; Bradley, Robert S; Hidalgo-Bastida, L Araida; Sherratt, Michael J; Cartmell, Sarah H

    2016-07-01

    Whereas the two-dimensional (2D) visualisation of biological samples is routine, three-dimensional (3D) imaging remains a time-consuming and relatively specialised pursuit. Current commonly adopted techniques for characterising the 3D structure of non-calcified tissues and biomaterials include optical and electron microscopy of serial sections and sectioned block faces, and the visualisation of intact samples by confocal microscopy or electron tomography. As an alternative to these approaches, X-ray computed micro-tomography (microCT) can both rapidly image the internal 3D structure of macroscopic volumes at sub-micron resolutions and visualise dynamic changes in living tissues at a microsecond scale. In this Commentary, we discuss the history and current capabilities of microCT. To that end, we present four case studies to illustrate the ability of microCT to visualise and quantify: (1) pressure-induced changes in the internal structure of unstained rat arteries, (2) the differential morphology of stained collagen fascicles in tendon and ligament, (3) the development of Vanessa cardui chrysalises, and (4) the distribution of cells within a tissue-engineering construct. Future developments in detector design and the use of synchrotron X-ray sources might enable real-time 3D imaging of dynamically remodelling biological samples. PMID:27278017

  12. As thick as three in a bed.

    Science.gov (United States)

    Scheidegger, Christoph

    2016-07-01

    During the evolution of the lichen symbiosis, shifts from one main type of photobiont to another were infrequent (Miadlikowska et al. ) but some remarkable transitions from green algal to diazotrophic cyanobacterial photobionts are known from unrelated fungal clades within the ascomycetes. Cyanobacterial, including tripartite, associations (green algal and cyanobacterial photobionts in one lichen individual) facilitate these holobionts to live as C- and N-autotrophs. Tripartite lichens are among the most productive lichens, which provide N-fertilization to forest ecosystems under oceanic climates (Peltigerales) or deliver low, but ecologically significant N-input into subarctic and alpine soil communities (Lecanorales, Agyriales). In this issue of Molecular Ecology, Schneider et al. (2016) mapped morphometric data against an eight-locus fungal phylogeny across a transition of photobiont interactions from green algal to a tripartite association and used a phylogenetic comparative framework to explore the role of nitrogen-fixing cyanobacteria in size differences in the Trapelia-Placopsis clade (Agyriales). Within the group of tripartite species, the volume of cyanobacteria-containing structures (cephalodia) correlates with thallus thickness in both phylogenetic generalized least squares and phylogenetic generalized linear mixed-effects analyses, and the fruiting body core volume increased ninefold. The authors conclude that cyanobacterial symbiosis appears to have enabled lichens to overcome size constraints in oligotrophic environments such as rock surfaces. The Trapelia-Placopsis clade analyzed by Schneider et al. (2016) is an exciting example of interactions between ecology, phylogeny and lichen biology including development - from thin crustose green algal microlichens to thick placodioid, tripartite macrolichens: as thick as three in a bed (Scott ).

  13. Eddy current thickness measurement apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, Gary J.; Sinclair, Frank; Soskov, Alexander; Buff, James S.

    2015-06-16

    A sheet of a material is disposed in a melt of the material. The sheet is formed using a cooling plate in one instance. An exciting coil and sensing coil are positioned downstream of the cooling plate. The exciting coil and sensing coil use eddy currents to determine a thickness of the solid sheet on top of the melt.

  14. On thickness of Saturn rings

    International Nuclear Information System (INIS)

    Electronographic plates of Saturn were taken during the transit of the Earth through the ring plane. Observing conditions were more favorable than those prevailing in 1966. Thanks to the quality of the detectors and the telescopes, it has been possible to make a more precise photometric determination of the brightness of the ring seen edge on and to measure the brightness variation with respect to the distance to the center of the planet. Extrapolating to the case where the elevation of the Earth above the ring plane is strictly zero, we deduce an apparent photometric ring thickness equal to 1.5+-0.3 km. For an homogeneous layer of small particles colliding inelastically, theory predicts a thickness of the order of a few particles radii, i.e. a few tens of meters. The observed brightness could be explained by the E ring, the brightness of large chunks, condensations and warping of the ring

  15. Accurate thickness measurement of graphene

    Science.gov (United States)

    Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.

    2016-03-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  16. Accurate thickness measurement of graphene.

    Science.gov (United States)

    Shearer, Cameron J; Slattery, Ashley D; Stapleton, Andrew J; Shapter, Joseph G; Gibson, Christopher T

    2016-03-29

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  17. Soliton models for thick branes

    Science.gov (United States)

    Peyravi, Marzieh; Riazi, Nematollah; Lobo, Francisco S. N.

    2016-05-01

    In this work, we present new soliton solutions for thick branes in 4+1 dimensions. In particular, we consider brane models based on the sine-Gordon (SG), φ 4 and φ 6 scalar fields, which have broken Z2 symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the w^2 term in the expansion of the potential for the resulting Schrödinger-like equation, where w is the five-dimensional coordinate. It turns out that the φ ^4 brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and φ ^6 branes.

  18. Soliton models for thick branes

    CERN Document Server

    Peyravi, Marzieh; Lobo, Francisco S N

    2015-01-01

    In this work, we present new soliton solutions for thick branes in $4+1$ dimensions. In particular, we consider brane models based on the sine-Gordon ($SG$), $\\varphi^{4}$ and $\\varphi^{6}$ scalar fields, which have broken $Z_{2}$ symmetry in some cases, and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacuua. These vacuua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighbourhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the $w^2$ term in the expansion of the potential for the resulting Schrodinger-like equation, where $w$ is the 5-dimensional coordinate. It turns out that the $\\phi^4$ brane is stable, while there are unstable modes for certain ranges of the model param...

  19. Soliton models for thick branes

    Energy Technology Data Exchange (ETDEWEB)

    Peyravi, Marzieh [Ferdowsi University of Mashhad, Department of Physics, School of Sciences, Mashhad (Iran, Islamic Republic of); Riazi, Nematollah [Shahid Beheshti University, Physics Department, Tehran (Iran, Islamic Republic of); Lobo, Francisco S.N. [Faculdade de Ciencias da Universidade de Lisboa, Instituto de Astrofisica e Ciencias do Espaco, Lisbon (Portugal)

    2016-05-15

    In this work, we present new soliton solutions for thick branes in 4+1 dimensions. In particular, we consider brane models based on the sine-Gordon (SG), φ{sup 4} and φ{sup 6} scalar fields, which have broken Z{sub 2} symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the w{sup 2} term in the expansion of the potential for the resulting Schroedinger-like equation, where w is the five-dimensional coordinate. It turns out that the φ{sup 4} brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and φ{sup 6} branes. (orig.)

  20. High-frequency ultrasonic imaging of thickly sliced specimens

    Science.gov (United States)

    Miyasaka, Chiaki; Tittmann, Bernhard R.; Chandraratna, Premindra A. N.

    2003-07-01

    It has been reported that a mechanical scanning reflection acoustic microscope (hereinafter called simply "SAM"), using high frequency ultrasonic tone-burst waves, can form a horizontal cross-sectional image (i.e., c-scan image) showing a highly resolved cellular structure of biological tissue. However, the tissue prepared for the SAM has been mostly a thinly sectioned specimen. In this study, the SAM images of specimens thickly sectioned from the tissue were analyzed. Optical and scanning acoustic microscopies were used to evaluate tissues of human small intestine and esophagus. For preparing thin specimens, the tissue was embedded in paraffin, and substantially sectioned at 5-10μm by the microtome. For optical microscopy, the tissue was stained with hematoxylin and eosin, and affixed onto glass substrates. For scanning acoustic microscopy, two types of specimens were prepared: thinly sectioned specimens affixed on the glass substrate, wherein the specimens were deparaffinized in xylene, but not stained, and thickely sectioned specimens. Images of the thick specimens obtained with frequency at 200 MHz revealed cellular structures. The morphology was very similar to that seen in the thinly sectioned specimens with optical and scanning acoustic microscopy. In addition, scanning electron microscopy was used to compare the images of biological tissue. An acoustic lens with frequency at 200 MHz permitted the imaging of surface and/or subsurface of microstructures in the thick sections of small intestine and esophagus.

  1. Biological computation

    CERN Document Server

    Lamm, Ehud

    2011-01-01

    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  2. Creating universes with thick walls

    Science.gov (United States)

    Ulvestad, Andrew; Albrecht, Andreas

    2012-05-01

    We study the dynamics of a spherically symmetric false vacuum bubble embedded in a true vacuum region separated by a “thick wall”, which is generated by a scalar field in a quartic potential. We study the “Farhi-Guth-Guven” (FGG) quantum tunneling process by constructing numerical solutions relevant to this process. The Arnowitt-Deser-Misner mass of the spacetime is calculated, and we show that there is a lower bound that is a significant fraction of the scalar field mass. We argue that the zero mass solutions used to by some to argue against the physicality of the FGG process are artifacts of the thin wall approximation used in earlier work. We argue that the zero mass solutions should not be used to question the viability of the FGG process.

  3. Creating universes with thick walls

    CERN Document Server

    Ulvestad, Andrew

    2012-01-01

    We study the dynamics of a spherically symmetric false vacuum bubble embedded in a true vacuum region separated by a "thick wall", which is generated by a scalar field in a quartic potential. We study the "Farhi-Guth-Guven" (FGG) quantum tunneling process by constructing numerical solutions relevant to this process. The ADM mass of the spacetime is calculated, and we show that there is a lower bound that is a significant fraction of the scalar field mass. We argue that the zero mass solutions used to by some to argue against the physicality of the FGG process are artifacts of the thin wall approximation used in earlier work. We argue that the zero mass solutions should not be used to question the viability of the FGG process.

  4. Thick Presentism and Newtonian Mechanics

    CERN Document Server

    Lubashevsky, Ihor

    2016-01-01

    In the present paper I argue that the formalism of Newtonian mechanics stems directly from the general principle to be called the principle of microlevel reducibility which physical systems obey in the realm of classical physics. This principle assumes, first, that all the properties of physical systems must be determined by their states at the current moment of time, in a slogan form it is "only the present matters to physics." Second, it postulates that any physical system is nothing but an ensemble of structureless particles arranged in some whose interaction obeys the superposition principle. I substantiate this statement and demonstrate directly how the formalism of differential equations, the notion of forces in Newtonian mechanics, the concept of phase space and initial conditions, the principle of least actions, etc. result from the principle of microlevel reducibility. The philosophical concept of thick presentism and the introduction of two dimensional time---physical time and meta-time that are mut...

  5. Functionalization of carbon nanotube and nanofiber electrodes with biological macromolecules: Progress toward a nanoscale biosensor

    Science.gov (United States)

    Baker, Sarah E.

    for surface chemistry for linking cytochrome c to nanofiber electrodes, and the resulting immobilized protein was determined to be active and was detected electrochemically using no electrochemical mediators. Additionally, we have developed an electrochemical functionalization method which allows for electrically-addressable biomolecular functionalization of patterned nanotubes and nanofibers. This method has enabled us to discretely functionalize individual sub-micron nanofiber regions with different DNA sequences on the same chip using no microfluidics, and will be useful for detection of multiple analytes on a single chip.

  6. Macular thickness and volume in the elderly

    DEFF Research Database (Denmark)

    Subhi, Yousif; Forshaw, Thomas; Sørensen, Torben Lykke

    2016-01-01

    manifests in the macula of the elderly focusing on clinical relevant measures that are thicknesses and volumes of different macular areas. Ageing seems to increase center point foveal thickness. Ageing does not seem to change the center subfield thickness significantly. Ageing decreases the inner and outer...

  7. Bilayer-thickness-mediated interactions between integral membrane proteins.

    Science.gov (United States)

    Kahraman, Osman; Koch, Peter D; Klug, William S; Haselwandter, Christoph A

    2016-04-01

    Hydrophobic thickness mismatch between integral membrane proteins and the surrounding lipid bilayer can produce lipid bilayer thickness deformations. Experiment and theory have shown that protein-induced lipid bilayer thickness deformations can yield energetically favorable bilayer-mediated interactions between integral membrane proteins, and large-scale organization of integral membrane proteins into protein clusters in cell membranes. Within the continuum elasticity theory of membranes, the energy cost of protein-induced bilayer thickness deformations can be captured by considering compression and expansion of the bilayer hydrophobic core, membrane tension, and bilayer bending, resulting in biharmonic equilibrium equations describing the shape of lipid bilayers for a given set of bilayer-protein boundary conditions. Here we develop a combined analytic and numerical methodology for the solution of the equilibrium elastic equations associated with protein-induced lipid bilayer deformations. Our methodology allows accurate prediction of thickness-mediated protein interactions for arbitrary protein symmetries at arbitrary protein separations and relative orientations. We provide exact analytic solutions for cylindrical integral membrane proteins with constant and varying hydrophobic thickness, and develop perturbative analytic solutions for noncylindrical protein shapes. We complement these analytic solutions, and assess their accuracy, by developing both finite element and finite difference numerical solution schemes. We provide error estimates of our numerical solution schemes and systematically assess their convergence properties. Taken together, the work presented here puts into place an analytic and numerical framework which allows calculation of bilayer-mediated elastic interactions between integral membrane proteins for the complicated protein shapes suggested by structural biology and at the small protein separations most relevant for the crowded membrane

  8. Bilayer-thickness-mediated interactions between integral membrane proteins

    Science.gov (United States)

    Kahraman, Osman; Koch, Peter D.; Klug, William S.; Haselwandter, Christoph A.

    2016-04-01

    Hydrophobic thickness mismatch between integral membrane proteins and the surrounding lipid bilayer can produce lipid bilayer thickness deformations. Experiment and theory have shown that protein-induced lipid bilayer thickness deformations can yield energetically favorable bilayer-mediated interactions between integral membrane proteins, and large-scale organization of integral membrane proteins into protein clusters in cell membranes. Within the continuum elasticity theory of membranes, the energy cost of protein-induced bilayer thickness deformations can be captured by considering compression and expansion of the bilayer hydrophobic core, membrane tension, and bilayer bending, resulting in biharmonic equilibrium equations describing the shape of lipid bilayers for a given set of bilayer-protein boundary conditions. Here we develop a combined analytic and numerical methodology for the solution of the equilibrium elastic equations associated with protein-induced lipid bilayer deformations. Our methodology allows accurate prediction of thickness-mediated protein interactions for arbitrary protein symmetries at arbitrary protein separations and relative orientations. We provide exact analytic solutions for cylindrical integral membrane proteins with constant and varying hydrophobic thickness, and develop perturbative analytic solutions for noncylindrical protein shapes. We complement these analytic solutions, and assess their accuracy, by developing both finite element and finite difference numerical solution schemes. We provide error estimates of our numerical solution schemes and systematically assess their convergence properties. Taken together, the work presented here puts into place an analytic and numerical framework which allows calculation of bilayer-mediated elastic interactions between integral membrane proteins for the complicated protein shapes suggested by structural biology and at the small protein separations most relevant for the crowded membrane

  9. Enhanced cortical thickness measurements for rodent brains via Lagrangian-based RK4 streamline computation

    Science.gov (United States)

    Lee, Joohwi; Kim, Sun Hyung; Oguz, Ipek; Styner, Martin

    2016-03-01

    The cortical thickness of the mammalian brain is an important morphological characteristic that can be used to investigate and observe the brain's developmental changes that might be caused by biologically toxic substances such as ethanol or cocaine. Although various cortical thickness analysis methods have been proposed that are applicable for human brain and have developed into well-validated open-source software packages, cortical thickness analysis methods for rodent brains have not yet become as robust and accurate as those designed for human brains. Based on a previously proposed cortical thickness measurement pipeline for rodent brain analysis,1 we present an enhanced cortical thickness pipeline in terms of accuracy and anatomical consistency. First, we propose a Lagrangian-based computational approach in the thickness measurement step in order to minimize local truncation error using the fourth-order Runge-Kutta method. Second, by constructing a line object for each streamline of the thickness measurement, we can visualize the way the thickness is measured and achieve sub-voxel accuracy by performing geometric post-processing. Last, with emphasis on the importance of an anatomically consistent partial differential equation (PDE) boundary map, we propose an automatic PDE boundary map generation algorithm that is specific to rodent brain anatomy, which does not require manual labeling. The results show that the proposed cortical thickness pipeline can produce statistically significant regions that are not observed in the previous cortical thickness analysis pipeline.

  10. Thickness monitor for floated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Ricketts, J.; Grecu, G.M.

    1989-10-31

    This patent describes apparatus for determining the thickness of a layer of aerated sludge floating on a layer of a heavier liquid in a tank. It comprises: a frame means which can be positioned to extend vertically into the tank; horizontally-extending indicator means supported by and moveable vertically with respect to a portion of the frame means extending vertically into the tank. The indicator means being selectively positionable at the highest level of sludge in the tank; horizontally-extending lower base means attached to the frame means at or near the bottom thereof; horizontally-extending upper base means attached to the frame means at or near the top thereof; and a line carrying a float means. The line being movable secured at the upper base means and the lower base means. The float means being floatable on the liquid and including a horizontally-extending portion presenting an upwardly directed generally planar surface, which surface will be parallel to the interface of the sludge and liquid.

  11. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  12. Biology Notes.

    Science.gov (United States)

    School Science Review, 1982

    1982-01-01

    Presents procedures, exercises, demonstrations, and information on a variety of biology topics including labeling systems, biological indicators of stream pollution, growth of lichens, reproductive capacity of bulbous buttercups, a straw balance to measure transpiration, interaction of fungi, osmosis, and nitrogen fixation and crop production. (DC)

  13. A Wavelet-Based Processing method for simultaneously determining ultrasonic velocity and material thickness

    OpenAIRE

    Loosvelt, Matthieu; Lasaygues, Philippe

    2011-01-01

    Methods of measuring ultrasonic wave velocity in an elastic sample require data on the thickness of the sample and/or the distances between the transducers and the sample. The uncertainty of the ultrasonic wave velocity measurements generally depends on that of the data available. Conversely, to determine the thickness of a material, it is necessary to have a priori information about the wave velocity. This problem is particularly hard to solve when measuring the parameters of biological spec...

  14. Ice thickness measurements by Raman scattering

    CERN Document Server

    Pershin, Sergey M; Klinkov, Vladimir K; Yulmetov, Renat N; Bunkin, Alexey F

    2014-01-01

    A compact Raman LIDAR system with a spectrograph was used for express ice thickness measurements. The difference between the Raman spectra of ice and liquid water is employed to locate the ice-water interface while elastic scattering was used for air-ice surface detection. This approach yields an error of only 2 mm for an 80-mm-thick ice sample, indicating that it is promising express noncontact thickness measurements technique in field experiments.

  15. Ultrasonic wall thickness measurement without coupling liquid

    International Nuclear Information System (INIS)

    If the material measured is part of the ultrasonic transducer, then one can do without the usual coupling liquid for ultrasonic measurement of wall thickness. Measuring equipment works on the basis of this electro-dynamic ultrasonic transducer, which has been developed to check the wall thickness (3 to 30 mm) of steel pipes with outside diameters of 25 to 180 mm. Double errors and local changes of wall thickness can be detected. (orig.)

  16. Dielectrophoretic capture of low abundance cell population using thick electrodes

    Science.gov (United States)

    Marchalot, Julien; Chateaux, Jean-François; Faivre, Magalie; Mertani, Hichem C.; Ferrigno, Rosaria; Deman, Anne-Laure

    2015-01-01

    Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force (FDEP) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10). PMID:26392836

  17. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  18. Skull thickness in patients with clefts

    DEFF Research Database (Denmark)

    Arntsen, T; Kjaer, I; Sonnesen, L;

    2010-01-01

    The purpose was to analyze skull thickness in incomplete cleft lip (CL), cleft palate (CP), and combined cleft lip and palate (UCLP).......The purpose was to analyze skull thickness in incomplete cleft lip (CL), cleft palate (CP), and combined cleft lip and palate (UCLP)....

  19. Monitoring Coating Thickness During Plasma Spraying

    Science.gov (United States)

    Miller, Robert A.

    1990-01-01

    High-resolution video measures thickness accurately without interfering with process. Camera views cylindrical part through filter during plasma spraying. Lamp blacklights part, creating high-contrast silhouette on video monitor. Width analyzer counts number of lines in image of part after each pass of spray gun. Layer-by-layer measurements ensure adequate coat built up without danger of exceeding required thickness.

  20. Fabrication of high quality sub-micron Au gratings over large areas with pulsed laser interference lithography for SPR sensors

    CERN Document Server

    Arriola, Alexander; Perez, Noemi; Tavera, Txaber; Withford, Michael J; Fuerbach, Alexander; Olaizola, Santiago M; 10.1364/OME.2.001571

    2013-01-01

    Metallic gratings were fabricated using high energy laser interference lithography with a frequency tripled Nd:YAG nanosecond laser. The grating structures were first recorded in a photosensitive layer and afterwards transferred to an Au film. High quality Au gratings with a period of 770 nm and peak-to-valley heights of 20-60 nm exhibiting plasmonic resonance response were successfully designed, fabricated and characterized.

  1. Global and local large-deformation response of sub-micron, soft- and hard-particle filled polycarbonate

    Science.gov (United States)

    Krop, Sam; Meijer, Han E. H.; van Breemen, Lambert C. A.

    2016-02-01

    Since polymers play an increasingly important role in both structural and tribological applications, understanding their intrinsic mechanical response is key. Therefore in the last few decades much effort has been devoted into the development of constitutive models that capture the polymers' intrinsic mechanical response quantitatively. An example is the Eindhoven Glassy Polymer model. In practice most polymers are filled, e.g. with hard particles or fibers, with colorants, or with soft particles that serve as impact modifiers. To characterize the influence of type and amount of filler particles on the intrinsic mechanical response, we designed model systems of polycarbonate with different volume fractions of small, order 100 nm sized, either hard or soft particles, and tested them in lubricated uniaxial compression experiments. To reveal the local effects on interparticle level, three-dimensional representative volume elements (RVEs) were constructed. The matrix material is modeled with the EGP model and the fillers with their individual mechanical properties. It is first shown that (only) 32 particles are sufficient to capture the statistical variations in these systems. Comparing the simulated response of the RVEs with the experiments demonstrates that in the small strain regime the stress is under-predicted since the polymer matrix is modeled by using only one single relaxation time. The yield- and the large strain response is captured well for the soft-particle filled systems while, for the hard-particles at increased filler loadings, the predictions are less accurate. This is likely caused by polymer-filler interactions that result in accelerated physical aging of the polymer matrix close to the surfaces. Modifying the Sa-parameter, that captures the thermodynamic state of the polymer matrix, allows us to correctly predict the macroscopic response after yield. The simulations reveal that all rate-dependencies of the different filled systems originate from that of the polymer matrix. Finally, an onset is presented to predict local and global failure based on critical events on the microlevel, that are likely to cause the over-prediction in the large-strain response of the hard-particle filled systems.

  2. The inhalation of insoluble iron oxide particles in the sub-micron ranges. Part II - Plutonium-237 labelled aerosols

    International Nuclear Information System (INIS)

    The results of a series of inhalation studies using iron oxide particles in the size range 0.1 to 0.3 um (count median diameter) are described. In this series the aerosols were labelled with plutonium 237. In vivo detection, excretion analysis and crude location studies were obtainable and the results compared to the earlier studies using chromium 51 labelled aerosols. Plutonium 237 can be considered as a simulator for plutonium 239 and attempts are made to extrapolate the results to the problem of the estimation of plutonium 239 in the human lung. (author)

  3. Effects of extrusion deformation on mechanical properties of sub-micron Si_3N_(4p)/2024 composite

    Institute of Scientific and Technical Information of China (English)

    XIU Zi-yang; CHEN Guo-qin; LIU Yan-mei; YANG Wen-shu; WU Gao-hui

    2009-01-01

    Si_3N_(4p)/2024Al composite was fabricated by squeeze casting method and treated by extrusion deformation. Microstructure analyses indicate that Si_3N_4 particles in the composite are in cylindrical polyhedron shape. Extrusion deformation is beneficial to uniform distribution of Si_3N_4 particles and improves the relative density of Si_3N_(4p)/2024Al composite. Tensile strength of Si_3N_(4p)/2024Al composite increases by 76.6% after T6 treatment, and after extrusion and T6 treatment it is by 57.6% more than T6 treatment only. Elastic modulus of Si_3N_(4p)/2024Al composite increases a little after T6 treatment but increases by 33.5% after extrusion deformation.

  4. A Nordic Project Project on High Speed Low Power Design in Sub-micron CMOS Technology for Mobile

    DEFF Research Database (Denmark)

    Olesen, Ole

    1997-01-01

    circuit design is based on state-of-the-art CMOS technology (0.5µm and below) including circuits operating at 2GHz. CMOS technology is chosen, since a CMOS implementation is likely to be significantly cheaper than a bipolar or a BiCMOS solution, and it offers the possibility to integrate the predominantly...... digital base-band processing on the same chip. Presently, only few examples of CMOS used for RF front-end circuits have been presented by academia, and so far no commercial products exist. The approach has been to do a CMOS block by block replacement of the blocks in traditional transceiver architectures...

  5. Sub-micron strain analysis of local stick-slip motion of individual shear bands in a bulk metallic glass

    Science.gov (United States)

    Binkowski, I.; Schlottbom, S.; Leuthold, J.; Ostendorp, S.; Divinski, S. V.; Wilde, G.

    2015-11-01

    Nanodot deposition on a side surface of a rectangular sample and digital image correlation are used to quantify the in-plane strain fields associated with the propagation of a shear band in a PdNiP bulk metallic glass, induced by rolling. Within the resolution of the method related to an average inter-dot distance of 100 nm, deformation is found to be highly localized at the shear bands, while alternating areas with a size of 100-400 nm with opposite local shear strains are found. This phenomenon substantiates a local stick-slip nature of shear band propagation during the metallic glass deformation, even during rolling.

  6. Sub-micron phase coexistence in small-molecule organic thin films revealed by infrared nano-imaging

    Science.gov (United States)

    Westermeier, Christian; Cernescu, Adrian; Amarie, Sergiu; Liewald, Clemens; Keilmann, Fritz; Nickel, Bert

    2014-06-01

    Controlling the domain size and degree of crystallization in organic films is highly important for electronic applications such as organic photovoltaics, but suitable nanoscale mapping is very difficult. Here we apply infrared-spectroscopic nano-imaging to directly determine the local crystallinity of organic thin films with 20-nm resolution. We find that state-of-the-art pentacene films (grown on SiO2 at elevated temperature) are structurally not homogeneous but exhibit two interpenetrating phases at sub-micrometre scale, documented by a shifted vibrational resonance. We observe bulk-phase nucleation of distinct ellipsoidal shape within the dominant pentacene thin-film phase and also further growth during storage. A faint topographical contrast as well as X-ray analysis corroborates our interpretation. As bulk-phase nucleation obstructs carrier percolation paths within the thin-film phase, hitherto uncontrolled structural inhomogeneity might have caused conflicting reports about pentacene carrier mobility. Infrared-spectroscopic nano-imaging of nanoscale polymorphism should have many applications ranging from organic nanocomposites to geologic minerals.

  7. Niobium nano-SQUIDs based on sub-micron tunnel junction fabricated by three-dimensional Focused Ion Beam sculpting

    Science.gov (United States)

    Fretto, M.; Enrico, E.; De Leo, N.; Boarino, L.; Lacquaniti, V.; Granata, C.; Russo, R.; Vettoliere, A.

    2014-05-01

    A three dimensional nano-SQUID (Superconducting Quantum Interference Device) has been realized in a vertical configuration (with the loop in the same plane of Josephson Tunneling Junctions, JTJs). The loop area is 0.25 μm2 corresponding to a modulation period of about 5 mT, the square JTJs have a side length of 0.3 μm. Josephson junction's fabrication is carried out combining optical lithography to pattern trilayer and three dimensional (3D) Focused Ion Beam (FIB) sculpting technique to define the junctions' and the loop's areas. Two different ion etching processes were performed, perpendicular and parallel to the multilayer, resulting in a precise 3D structure. Finally, a standard anodization was performed to eliminate the unstructured surface material generated by the high energetic ion beam assuring high quality junctions. Electric transport characteristics of the nanodevice measured at T = 4.2 K are reported, in particular the current-voltage characteristics and critical current vs external magnetic field. The high modulation depth of the critical current (up to 70% of the Ic at zero magnetic flux) and the device reliability are very encouraging in view of nanoscience applications.

  8. The Smallest Lunar Grains: Analytical TEM Characterization of the Sub-micron Size Fraction of a Mare Soil

    Science.gov (United States)

    Thompson, M.; Christoffersen, R.

    2010-01-01

    The chemical composition, mineralogical type, and morphology of lunar regolith grains changes considerably with decreasing size, and below the approx.25 m size range the correlation between these parameters and remotely-sensed lunar surface properties connected to space weathering increases significantly. Although trends for these parameters across grain size intervals greater than 20 m are now well established, the 0 to 20 m size interval remains relatively un-subdivided with respect to variations in grain modal composition, chemistry and microstructure. Of particular interest in this size range are grains in the approximate analytical transmission electron microscopy (TEM) to characterize the mineralogy, microstructure and major element composition of grains below the 1 m size threshold in lunar soil 10084.

  9. Characterization and analysis of sub-micron surface roughness of injection moulded microfluidic systems using White Light Interferometry

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2009-01-01

    Surface topography is of great importance in polymer micro fluidics, therefore the replication capability of the process and the surface quality of the tool has to be suitably optimized. In this paper, optical profilometry (white light interferometry, WLI) is implemented for topographical...

  10. Characterization and analysis of micro channels and sub-micron surface roughness of injection moulded microfluidic systems using optical metrology

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2009-01-01

    measuring machine and a white light interferometer respectively. The effect of the dimensional scale range on the micro/nano features replication was evaluated and it was found to be the dominant parameter if compared with the effect of the other process-related parameters investigated (melt and mould...

  11. Characterization and analysis of micro channels and sub-micron surface roughness of injection moulded microfluidic systems using optical metrology

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2012-01-01

    measuring machine and a white light interferometer respectively. The effect of the dimensional scale range on the micro/nano features replication was evaluated and it was found to be the dominant parameter if compared with the effect of the other process-related parameters investigated (melt and mould...

  12. Fast and precise algorithms for calculating offset correction in single photon counting ASICs built in deep sub-micron technologies

    Science.gov (United States)

    Maj, P.

    2014-07-01

    An important trend in the design of readout electronics working in the single photon counting mode for hybrid pixel detectors is to minimize the single pixel area without sacrificing its functionality. This is the reason why many digital and analog blocks are made with the smallest, or next to smallest, transistors possible. This causes a problem with matching among the whole pixel matrix which is acceptable by designers and, of course, it should be corrected with the use of dedicated circuitry, which, by the same rule of minimizing devices, suffers from the mismatch. Therefore, the output of such a correction circuit, controlled by an ultra-small area DAC, is not only a non-linear function, but it is also often non-monotonic. As long as it can be used for proper correction of the DC operation points inside each pixel, it is acceptable, but the time required for correction plays an important role for both chip verification and the design of a big, multi-chip system. Therefore, we present two algorithms: a precise one and a fast one. The first algorithm is based on the noise hits profiles obtained during so called threshold scan procedures. The fast correction procedure is based on the trim DACs scan and it takes less than a minute in a SPC detector systems consisting of several thousands of pixels.

  13. Effects of phase explosion in pulsed laser deposition of nickel thin film and sub-micron droplets

    Energy Technology Data Exchange (ETDEWEB)

    Siew, W.O.; Yapl, S.S.; Yong, T.K.; Nee, C.H. [Faculty of Engineering, Multimedia University, Cyberjaya 63100, Selangor (Malaysia); Tou, T.Y., E-mail: tytou@mmu.edu.my [Faculty of Engineering, Multimedia University, Cyberjaya 63100, Selangor (Malaysia)

    2011-01-15

    Nickel (Ni) thin films were deposited on glass substrates in high vacuum and at room temperature with third-harmonic or 355-nm output from a nanosecond Nd:YAG laser. At low laser fluence of 1 J/cm{sup 2}, the deposition rate was about 0.0016 nm/shot which increased linearly until 4 J/cm{sup 2}. Above 4 J/cm{sup 2}, the onset of phase explosion in the ablation abruptly increased the optical emission intensity from laser-produced Ni plume as well as thin-film deposition rate by about 6x. The phase explosion also shifted the size distribution and number density of Ni droplets on its thin-film surface. On the other hand, the surface structures of the ablated Ni targets were compared between the scan-mode and the fixed-mode ablations, which may suggest that droplets observed on the thin-film surface were caused by direct laser-induced splashing of molten Ni rather than vapour-to-cluster condensation during the plume propagation.

  14. Stochastic limits in synchronous imaging of sub-micron magnetization dynamics using scanning transmission x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cheng C.; Kaznatcheev K.; Bailey, W.E.

    2012-02-28

    We demonstrate a synchronous (lock-in) technique for imaging thin-film magnetization dynamics using scanning transmission x-ray microscopy (STXM). Gated photon counting synchronized with magnetic field modulation allows image acquisition with differential contrast for high and low magnetization. We have applied this technique to 5 x 12 {micro}m{sup 2} Ni{sub 81}Fe{sub 19} ellipses with well-defined closure domains at remanence. The stochastic nature of the domain wall motion and nucleation is apparent in images recorded during cycling along successive major hysteresis loops. Synchronous imaging shows the clearest enhancement of contrast for small-amplitude domain wall motion, with a less obvious benefit at higher fields/displacements. The technique shows promise for the contrast enhancement of magnetization in dynamics in STXM.

  15. Quantum Biology

    CERN Document Server

    Sergi, Alessandro

    2009-01-01

    A critical assessment of the recent developments of molecular biology is presented. The thesis that they do not lead to a conceptual understanding of life and biological systems is defended. Maturana and Varela's concept of autopoiesis is briefly sketched and its logical circularity avoided by postulating the existence of underlying {\\it living processes}, entailing amplification from the microscopic to the macroscopic scale, with increasing complexity in the passage from one scale to the other. Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces, is criticized. It is suggested that the correct interpretation of quantum dispersion forces (van der Waals, hydrogen bonding, and so on) as quantum coherence effects hints at the necessity of including long-ranged forces (or mechanisms for them) in condensed matter theories of biological processes. Some quantum effects in biology are reviewed and quantum mechanics is acknowledge...

  16. The thickness of amalgamations of graphs

    CERN Document Server

    Yang, Yan

    2012-01-01

    The thickness $\\theta(G)$ of a graph $G$ is the minimum number of planar spanning subgraphs into which the graph $G$ can be decomposed. As a topological invariant of a graph, it is a measurement of the closeness to planarity of a graph, and it also has important applications to VLSI design. In this paper, the thickness of graphs that are obtained by vertex-amalgamation and bar-amalgamation of any two graphs whose thicknesses are known are obtained, respectively. And the lower and upper bounds for the thickness of graphs that are obtained by edge-amalgamation and 2-vertex-amalgamation of any two graphs whose thicknesses are known are also derived, respectively.

  17. Practical considerations in ultrasonic wall thickness measurement

    International Nuclear Information System (INIS)

    Ultrasonic inspection is widely used by industry for the detection of corrosion and the measurement of material wall thickness. Due to wall thinning and the various forms of corrosion that can be found in pressure piping and pressure vessels the annual cost of corrosion damage and related service failures, is very expensive. The author interest is primarily in the examination of personnel who need to become competent and certificated in the various skills that are required to carry out wall thickness measurement and detection of wall thinning due to corrosion. The various techniques and equipment available for ultrasonic wall thickness measurement and assessment give rise to problems regarding the accuracy of results and detection of corrosion. This paper will discuss some of the corrosion conditions that may occur and also problems that may arise during wall thickness measurement. Methods of improving the wall thickness measurement and the assessment process will also be discussed. (author)

  18. Integrated Raman and angular scattering of single biological cells

    Science.gov (United States)

    Smith, Zachary J.

    2009-12-01

    Raman, or inelastic, scattering and angle-resolved elastic scattering are two optical processes that have found wide use in the study of biological systems. Raman scattering quantitatively reports on the chemical composition of a sample by probing molecular vibrations, while elastic scattering reports on the morphology of a sample by detecting structure-induced coherent interference between incident and scattered light. We present the construction of a multimodal microscope platform capable of gathering both elastically and inelastically scattered light from a 38 mum2 region in both epi- and trans-illumination geometries. Simultaneous monitoring of elastic and inelastic scattering from a microscopic region allows noninvasive characterization of a living sample without the need for exogenous dyes or labels. A sample is illuminated either from above or below with a focused 785 nm TEM00 mode laser beam, with elastic and inelastic scattering collected by two separate measurement arms. The measurements may be made either simultaneously, if identical illumination geometries are used, or sequentially, if the two modalities utilize opposing illumination paths. In the inelastic arm, Stokes-shifted light is dispersed by a spectrograph onto a CCD array. In the elastic scattering collection arm, a relay system images the microscope's back aperture onto a CCD detector array to yield an angle-resolved elastic scattering pattern. Post-processing of the inelastic scattering to remove fluorescence signals yields high quality Raman spectra that report on the sample's chemical makeup. Comparison of the elastically scattered pupil images to generalized Lorenz-Mie theory yields estimated size distributions of scatterers within the sample. In this thesis we will present validations of the IRAM instrument through measurements performed on single beads of a few microns in size, as well as on ensembles of sub-micron particles of known size distributions. The benefits and drawbacks of the

  19. Three-dimensional bioprinting of thick vascularized tissues.

    Science.gov (United States)

    Kolesky, David B; Homan, Kimberly A; Skylar-Scott, Mark A; Lewis, Jennifer A

    2016-03-22

    The advancement of tissue and, ultimately, organ engineering requires the ability to pattern human tissues composed of cells, extracellular matrix, and vasculature with controlled microenvironments that can be sustained over prolonged time periods. To date, bioprinting methods have yielded thin tissues that only survive for short durations. To improve their physiological relevance, we report a method for bioprinting 3D cell-laden, vascularized tissues that exceed 1 cm in thickness and can be perfused on chip for long time periods (>6 wk). Specifically, we integrate parenchyma, stroma, and endothelium into a single thick tissue by coprinting multiple inks composed of human mesenchymal stem cells (hMSCs) and human neonatal dermal fibroblasts (hNDFs) within a customized extracellular matrix alongside embedded vasculature, which is subsequently lined with human umbilical vein endothelial cells (HUVECs). These thick vascularized tissues are actively perfused with growth factors to differentiate hMSCs toward an osteogenic lineage in situ. This longitudinal study of emergent biological phenomena in complex microenvironments represents a foundational step in human tissue generation.

  20. Three-dimensional bioprinting of thick vascularized tissues

    Science.gov (United States)

    Kolesky, David B.; Homan, Kimberly A.; Skylar-Scott, Mark A.; Lewis, Jennifer A.

    2016-03-01

    The advancement of tissue and, ultimately, organ engineering requires the ability to pattern human tissues composed of cells, extracellular matrix, and vasculature with controlled microenvironments that can be sustained over prolonged time periods. To date, bioprinting methods have yielded thin tissues that only survive for short durations. To improve their physiological relevance, we report a method for bioprinting 3D cell-laden, vascularized tissues that exceed 1 cm in thickness and can be perfused on chip for long time periods (>6 wk). Specifically, we integrate parenchyma, stroma, and endothelium into a single thick tissue by coprinting multiple inks composed of human mesenchymal stem cells (hMSCs) and human neonatal dermal fibroblasts (hNDFs) within a customized extracellular matrix alongside embedded vasculature, which is subsequently lined with human umbilical vein endothelial cells (HUVECs). These thick vascularized tissues are actively perfused with growth factors to differentiate hMSCs toward an osteogenic lineage in situ. This longitudinal study of emergent biological phenomena in complex microenvironments represents a foundational step in human tissue generation.

  1. The Galactic Thick Disk Stellar Abundances

    CERN Document Server

    Prochaska, J X; Carney, B W; McWilliam, A; Wolfe, A M; Prochaska, Jason X.; Naumov, Sergei O.; Carney, Bruce W.; William, Andrew Mc; Wolfe, Arthur M.

    2000-01-01

    We present first results from a program to measure the chemical abundances of a large (N>30) sample of thick disk stars with the principal goal of investigating the formation history of the Galactic thick disk. Our analysis confirms previous studies of O and Mg in the thick disk stars which reported enhancements in excess of the thin disk population. Furthermore, the observations of Si, Ca, Ti, Mn, Co, V, Zn, Al, and Eu all argue that the thick disk population has a distinct chemical history from the thin disk. With the exception of V and Co, the thick disk abundance patterns match or tend towards the values observed for halo stars with [Fe/H]~-1. This suggests that the thick disk stars had a chemical enrichment history similar to the metal-rich halo stars. With the possible exception of Si, the thick disk abundance patterns are in excellent agreement with the chemical abundances observed in the metal-poor bulge stars suggesting the two populations formed from the same gas reservoir at a common epoch. We disc...

  2. Do thick leaves avoid thermal damage in critically low wind speeds?

    Science.gov (United States)

    Leigh, A; Sevanto, S; Ball, M C; Close, J D; Ellsworth, D S; Knight, C A; Nicotra, A B; Vogel, S

    2012-04-01

    Transient lulls in air movement are rarely measured, but can cause leaf temperature to rise rapidly to critical levels. The high heat capacity of thick leaves can damp this rapid change in temperature. However, little is known about the extent to which increased leaf thickness can reduce thermal damage, or how thick leaves would need to be to have biological significance. We evaluated quantitatively the contribution of small increases in leaf thickness to the reduction in thermal damage during critically low wind speeds under desert conditions. We employed a numerical model to investigate the effect of thickness relative to transpiration, absorptance and leaf size on damage avoidance. We used measured traits and thermotolerance thresholds of real leaves to calculate the leaf temperature response to naturally occurring variable low wind speed. Our results demonstrated that an increase in thickness of only fractions of a millimetre can prevent excursions to damaging high temperatures. This damping effect of increased thickness was greatest when other means of reducing leaf temperature (transpiration, reflectance or reduced size) were lacking. For perennial desert flora, we propose that increased leaf thickness is important in decreasing the incidence of extreme heat stress and, in some species, in enhancing long-term survival. PMID:22296328

  3. Film thickness determination by grazing incidence diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Battiston, G. A.; Gerbasi, R. [CNR, Padua (Italy). Istituto di Chimica e Tecnologie Inorganiche e dei Materiali Avanzati

    1996-09-01

    Thin films deposited via MOCVD (Metal Organic Chemical Vapour Deposition) are layers in the thickness range of a few manometers to about ten micrometers. An understanding of the physics and chemistry of films is necessary for a better comprehension of the phenomena involved in the film deposition procedure and its optimisation. Together with the crystalline phase a parameter that must be determined is the thickness of the layer. In this work the authors present a method for the measurement of the film thickness. This procedure, based on diffraction intensity absorption of the X-rays, both incident and diffracted in passing through the layers, resulted quite simple, rapid and non-destructive.

  4. Characterisation of the Galactic thick disk

    CERN Document Server

    Bensby, Thomas

    2013-01-01

    Thick disks appear to be common in external large spiral galaxies and our own Milky Way also hosts one. The existence of a thick disk is possibly directly linked to the formation history of the host galaxy and if its properties is known it can constrain models of galaxy formation and help us to better understand galaxy formation and evolution. This brief review attempts to highlight some of the characteristics of the Galactic thick disk and how it relates to other stellar populations such as the thin disk and the Galactic bulge. Focus has been put on results from high-resolution spectroscopic data obtained during the last 10 to 15 years.

  5. Biological Oceanography

    Science.gov (United States)

    Abbott, M. R.

    1984-01-01

    Within the framework of global biogeochemical cycles and ocean productivity, there are two areas that will be of particular interest to biological oceanography in the 1990s. The first is the mapping in space time of the biomass and productivity of phytoplankton in the world ocean. The second area is the coupling of biological and physical processes as it affects the distribution and growth rate of phytoplankton biomass. Certainly other areas will be of interest to biological oceanographers, but these two areas are amenable to observations from satellites. Temporal and spatial variability is a regular feature of marine ecosystems. The temporal and spatial variability of phytoplankton biomass and productivity which is ubiquitous at all time and space scales in the ocean must be characterized. Remote sensing from satellites addresses these problems with global observations of mesocale (2 to 20 days, 10 to 200 km) features over a long period of time.

  6. A database of worldwide glacier thickness observations

    DEFF Research Database (Denmark)

    Gärtner-Roer, I.; Naegeli, K.; Huss, M.;

    2014-01-01

    One of the grand challenges in glacier research is to assess the total ice volume and its global distribution. Over the past few decades the compilation of a world glacier inventory has been well-advanced both in institutional set-up and in spatial coverage. The inventory is restricted to glacier...... surface observations. However, although thickness has been observed on many glaciers and ice caps around the globe, it has not yet been published in the shape of a readily available database. Here, we present a standardized database of glacier thickness observations compiled by an extensive literature...... review and from airborne data extracted from NASA's Operation IceBridge. This database contains ice thickness observations from roughly 1100 glaciers and ice caps including 550 glacier-wide estimates and 750,000 point observations. A comparison of these observational ice thicknesses with results from...

  7. Greenland Radar Ice Sheet Thickness Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — Two 150-MHz coherent radar depth sounders were developed and flown over the Greenland ice sheet to obtain ice thickness measurements in support of PARCA...

  8. Russian River Ice Thickness and Duration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of river ice thickness measurements, and beginning and ending dates for river freeze-up events from fifty stations in northern Russia. The...

  9. Saturated thickness, High Plains aquifer, 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This raster data set represents the saturated thickness of the High Plains aquifer of the United States, 2009, in feet. The High Plains aquifer underlies...

  10. Intrinsic Thickness of QCD Flux-Tubes

    CERN Document Server

    Vyas, Vikram

    2010-01-01

    The effects of finite intrinsic thickness of QCD flux-tubes are explored using gauge/gravity duality under the assumptions that the position of the string in the fifth dimension is related to the intrinsic thickness of the QCD flux-tube, and the action of the five-dimensional fundamental string is the Nambu-Goto action. Under these assumptions the static quark-antiquark potential is calculated in the large d approximation, where d is the number of transverse direction in the flat space where the gauge theory lives. The potential is found to be given by Arvis's formula corrected by an exponentially suppressed term, which can be thought of as arising from the fluctuations of the intrinsic thickness of the QCD flux-tube. This result suggests that when the effects of intrinsic thickness can be ignored, then the four-dimensional effective string theory is just the Nambu-Goto string with no additional marginal or irrelevant terms.

  11. APPLIED ORIGAMI. Origami of thick panels.

    Science.gov (United States)

    Chen, Yan; Peng, Rui; You, Zhong

    2015-07-24

    Origami patterns, including the rigid origami patterns in which flat inflexible sheets are joined by creases, are primarily created for zero-thickness sheets. In order to apply them to fold structures such as roofs, solar panels, and space mirrors, for which thickness cannot be disregarded, various methods have been suggested. However, they generally involve adding materials to or offsetting panels away from the idealized sheet without altering the kinematic model used to simulate folding. We develop a comprehensive kinematic synthesis for rigid origami of thick panels that differs from the existing kinematic model but is capable of reproducing motions identical to that of zero-thickness origami. The approach, proven to be effective for typical origami, can be readily applied to fold real engineering structures. PMID:26206928

  12. Wilcox Group Apparent Thickness, Gulf Coast (wlcxthkg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Apparent Wilcox Group thickness maps are contoured from location and top information derived from the Petroleum Information (PI) Wells database. The Wilcox...

  13. Histological Stratification of Thick and Thin Plaque Psoriasis Explores Molecular Phenotypes with Clinical Implications.

    Directory of Open Access Journals (Sweden)

    Jaehwan Kim

    Full Text Available Psoriasis, which presents as red, scaly patches on the body, is a common, autoimmune skin disease that affects 2 to 3 percent of the world population. To leverage recent molecular findings into the personalized treatment of psoriasis, we need a strategy that integrates clinical stratification with molecular phenotyping. In this study, we sought to stratify psoriasis patients by histological measurements of epidermal thickness, and to compare their molecular characterizations by gene expression, serum cytokines, and response to biologics. We obtained histological measures of epidermal thickness in a cohort of 609 psoriasis patients, and identified a mixture of two subpopulations-thick and thin plaque psoriasis-from which they were derived. This stratification was verified in a subcohort of 65 patients from a previously published study with significant differences in inflammatory cell infiltrates in the psoriatic skin. Thick and thin plaque psoriasis shared 84.8% of the meta-analysis-derived psoriasis transcriptome, but a stronger dysregulation of the meta-analysis-derived psoriasis transcriptome was seen in thick plaque psoriasis on microarray. RT-PCR revealed that gene expression in thick and thin plaque psoriasis was different not only within psoriatic lesional skin but also in peripheral non-lesional skin. Additionally, differences in circulating cytokines and their changes in response to biologic treatments were found between the two subgroups. All together, we were able to integrate histological stratification with molecular phenotyping as a way of exploring clinical phenotypes with different expression levels of the psoriasis transcriptome and circulating cytokines.

  14. Definitions of radioisotope thick target yields

    Energy Technology Data Exchange (ETDEWEB)

    Otuka, Naohiko [International Atomic Energy Agency, Wien (Austria). Nuclear Data Section; Takacs, Sandor [Hungarian Academy of Science, Debrecen (Hungary). Inst. of Nuclear Research

    2015-05-01

    Definitions of thick target yields are reviewed in relation to their documentation for the experimental nuclear reaction data library (database). Researchers reporting experimental thick target yields are urged to define their yields clearly with an appropriate unit in order to compile them in the experimental data library (EXFOR) in a consistent manner, and also to properly utilise them for comparison with other experimental and evaluated yields.

  15. The normal choroidal thickness in southern Thailand

    Directory of Open Access Journals (Sweden)

    Jirarattanasopa P

    2014-11-01

    Full Text Available Pichai Jirarattanasopa,1 Nisa Panon,2 Siriphun Hiranyachattada,2 Patama Bhurayanontachai1 1Department of Ophthalmology, Faculty of Medicine, 2Department of Physiology, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand Objective: To investigate the association between subfoveal choroidal thickness in healthy southern Thailand volunteers and age, axial length, and refractive error.Subjects and methods: This was a prospective cross-sectional case series. A total of 210 eyes of 105 healthy volunteers (86 women, age 23–83 years in southern Thailand were examined with enhanced depth-imaging optical coherence tomography. Subjects with systemic diseases that may affect the choroidal vascular blood vessels, such as diabetes, impaired renal function, and hypertension, were excluded. Refractive error and axial length were measured by autorefractometry and an IOLMaster, respectively. Subfoveal choroidal thickness was measured from the outer border of the retinal pigment epithelium to the inner scleral border in the subfoveal area.Results: The mean subfoveal choroidal thickness was 279.4±75.49 µm, and the mean age was 46.4±16.45 years. Subfoveal choroidal thickness was negatively correlated with age (r2=0.33, P<0.0001 and axial length (r2=0.02, P<0.02. Multivariable regression analysis showed subfoveal choroidal thickness was positively and negatively correlated with a spherical equivalent refractive error and axial length, respectively, when adjusted for age.Conclusion: Age is the most important factor in choroidal thickness rather than axial length and refractive error. Subfoval choroidal thickness was decreased 2.67 µm every year and 14.59 µm with 1 mm increase in axial length. Keywords: choroidal thickness, enhanced depth-imaging optical coherence tomography, swept-source optical coherence tomography

  16. Thick Film Temperature Sensors Using Standard Pastes

    OpenAIRE

    M. R. Haskard; Janoska, I.

    1986-01-01

    Standard thick film resistor pastes exhibit changes in their electrical characteristics when printed on top of dielectric layers. Of particular interest is the inherent change in their temperature coefficient of resistance. Simple temperature sensors were formed by deliberately printing thick film resistor pastes on top of larger area dielectric layers. Temperature tests carried out on these devices have shown that by selecting the correct paste combination and resistor aspect ratio stable, r...

  17. LMC Microlensing and Very Thick Disks

    OpenAIRE

    Gyuk, Geza; Gates, Evalyn

    1998-01-01

    We investigate the implications of a very thick (scale height 1.5 - 3.0 kpc) disk population of MACHOs. Such a population represents a reasonable alternative to standard halo configurations of a lensing population. We find that very thick disk distributions can lower the lens mass estimate derived from the microlensing data toward the LMC, although an average lens mass substantially below $0.3\\Msol$ is unlikely. Constraints from direct searches for such lenses imply very low luminosity object...

  18. Rapid Measurement of Nanoparticle Thickness Profiles

    Energy Technology Data Exchange (ETDEWEB)

    Katz-Boon, Hadas, E-mail: hadas.katz@monash.edu [Department of Materials Engineering, Monash University, VIC 3800 (Australia); Rossouw, Chris J. [Monash Centre for Electron Microscopy, Monash University, VIC 3800 (Australia); Dwyer, Christian; Etheridge, Joanne [Department of Materials Engineering, Monash University, VIC 3800 (Australia); Monash Centre for Electron Microscopy, Monash University, VIC 3800 (Australia)

    2013-01-15

    A method to measure the thickness of a single-crystal nanoparticle in the direction parallel to the incident beam from annular dark field scanning transmission electron microscope (ADF-STEM) images is reported, providing a map of thickness versus position across the nanoparticle-a 'thickness profile' image. The method is rapid and hence suitable for surveying large numbers of nanoparticles. The method measures the intensity scattered to a characterised ADF detector and compares this to the incident beam intensity, to obtain a normalized ADF image. The normalised intensity is then converted to thickness via dynamical ADF image simulations. The method is accurate within 10% and the precision is dominated primarily by 'shot noise'. Merits and limitations of this method are discussed. A method to calibrate the response function of the ADF detector without external equipment is also described, which is applicable to the entire range of gain and background settings. -- Highlights: Black-Right-Pointing-Pointer A method is developed to convert ADF-STEM images to 'thickness profile' images. Black-Right-Pointing-Pointer It is applicable in particles survey, facets determination and discrete tomography. Black-Right-Pointing-Pointer A method to calibrate the response of the ADF detector is described. Black-Right-Pointing-Pointer The response in analysed across a range of conditions. Black-Right-Pointing-Pointer Dynamical ADF image simulations are presented, demonstrating intensity vs. thickness dependence.

  19. Elastic stability of thick auxetic plates

    International Nuclear Information System (INIS)

    Auxetic materials and structures exhibit a negative Poisson’s ratio while thick plates encounter shear deformation, which is not accounted for in classical plate theory. This paper investigates the effect of a negative Poisson’s ratio on thick plates that are subjected to buckling loads, taking into consideration the shear deformation using Mindlin plate theory. Using a highly accurate shear correction factor that allows for the effect of Poisson’s ratio, the elastic stability of circular and square plates are evaluated in terms of dimensionless parameters, namely the Mindlin-to-Kirchhoff critical buckling load ratio and Mindlin critical buckling load factors. Results for thick square plates reveal that both parameters increase as the Poisson’s ratio becomes more negative. In the case of thick circular plates, the Mindlin-to-Kirchhoff critical buckling load ratios and the Mindlin critical buckling load factors increase and decrease, respectively, as the Poisson’s ratio becomes more negative. The results obtained herein show that thick auxetic plates behave as thin conventional plates, and therefore suggest that the classical plate theory can be used to evaluate the elastic stability of thick plates if the Poisson’s ratio of the plate material is sufficiently negative. The results also suggest that materials with highly negative Poisson’s ratios are recommended for square plates, but not circular plates, that are subjected to buckling loads. (paper)

  20. Ice Thickness in the Northwest Passage

    Science.gov (United States)

    Haas, C.; Howell, S.

    2015-12-01

    Recently the feasibility of commercial shipping in the ice-prone Northwest Passage has attracted a lot of attention. However, very little ice thickness information actually exists. We present results of the first-ever airborne electromagnetic ice thickness surveys over the NWP carried out in April and May 2011 and 2015 over first-year and multiyear ice. Results show modal thicknesses between 1.8 and 2.0 m in all regions. Mean thicknesses over 3 m and thick, deformed ice were observed over some multiyear ice regimes shown to originate from the Arctic Ocean. Thick ice features more than 100 m wide and thicker than 4 m occurred frequently. There are few other data to compare with to evaluate if the ice of the Northwest Passage has transitioned as other parts of the Arctic have. Although likely thinner than some 20 or more years ago, ice conditions must still be considered severe, and the Canadian Arctic Archipelao may well be considered the last ice refuge of the Arctic. These results have important implications for the prediction of ice break-up and summer ice conditions, and the assessment of sea ice hazards during the summer shipping season.

  1. Biology Notes.

    Science.gov (United States)

    School Science Review, 1981

    1981-01-01

    Outlines a variety of laboratory procedures, techniques, and materials including construction of a survey frame for field biology, a simple tidal system, isolation and applications of plant protoplasts, tropisms, teaching lung structure, and a key to statistical methods for biologists. (DS)

  2. (Biological dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  3. Biology Notes.

    Science.gov (United States)

    School Science Review, 1984

    1984-01-01

    Presents information on the teaching of nutrition (including new information relating to many current O-level syllabi) and part 16 of a reading list for A- and S-level biology. Also includes a note on using earthworms as a source of material for teaching meiosis. (JN)

  4. Rifting Thick Lithosphere - Canning Basin, Western Australia

    Science.gov (United States)

    Czarnota, Karol; White, Nicky

    2016-04-01

    The subsidence histories and architecture of most, but not all, rift basins are elegantly explained by extension of ~120 km thick lithosphere followed by thermal re-thickening of the lithospheric mantle to its pre-rift thickness. Although this well-established model underpins most basin analysis, it is unclear whether the model explains the subsidence of rift basins developed over substantially thick lithosphere (as imaged by seismic tomography beneath substantial portions of the continents). The Canning Basin of Western Australia is an example where a rift basin putatively overlies lithosphere ≥180 km thick, imaged using shear wave tomography. Subsidence modelling in this study shows that the entire subsidence history of the Canning Basin is adequately explained by mild Ordovician extension (β≈1.2) of ~120 km thick lithosphere followed by post-rift thermal subsidence. This is consistent with the established model, described above, albeit with perturbations due to transient dynamic topography support which are expressed as basin-wide unconformities. In contrast the Canning Basin reveals an almost continuous period of normal faulting between the Ordovician and Carboniferous (βCanning Basin to rifting of thick lithosphere beneath the eastern part, verified by the presence of ~20 Ma diamond-bearing lamproites intruded into the basin depocentre. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted in density by 50-70 kg m-3, which is in line with estimates derived from modelling rare-earth element concentrations of the ~20 Ma lamproites and global isostatic considerations. Together, these results suggest that thick lithosphere thinned to > 120 km is thermally stable and is not accompanied by post-rift thermal subsidence driven by thermal re-thickening of the lithospheric mantle. Our results show that variations in lithospheric thickness place a fundamental control on basin architecture

  5. Quantitative mapping of collagen fiber alignment in thick tissue samples using transmission polarized-light microscopy.

    Science.gov (United States)

    Yakovlev, Dmitry D; Shvachkina, Marina E; Sherman, Maria M; Spivak, Andrey V; Pravdin, Alexander B; Yakovlev, Dmitry A

    2016-07-01

    Immersion optical clearing makes it possible to use transmission polarized-light microscopy for characterization of thick (200 to 2000  μm) layers of biological tissues. We discuss polarization properties of thick samples in the context of the problem of characterization of collagen fiber alignment in connective tissues such as sclera and dermis. Optical chirality caused by azimuthal variations of the macroscopic (effective) optic axis of the medium across the sample thickness should be considered in polarization mapping of thick samples of these tissues. We experimentally evaluate to what extent the optical chirality affects the measurement results in typical situations and show under what conditions it can be easily taken into account and does not hinder, but rather helps, in characterization of collagen fiber alignment.

  6. Quantitative mapping of collagen fiber alignment in thick tissue samples using transmission polarized-light microscopy

    Science.gov (United States)

    Yakovlev, Dmitry D.; Shvachkina, Marina E.; Sherman, Maria M.; Spivak, Andrey V.; Pravdin, Alexander B.; Yakovlev, Dmitry A.

    2016-07-01

    Immersion optical clearing makes it possible to use transmission polarized-light microscopy for characterization of thick (200 to 2000 μm) layers of biological tissues. We discuss polarization properties of thick samples in the context of the problem of characterization of collagen fiber alignment in connective tissues such as sclera and dermis. Optical chirality caused by azimuthal variations of the macroscopic (effective) optic axis of the medium across the sample thickness should be considered in polarization mapping of thick samples of these tissues. We experimentally evaluate to what extent the optical chirality affects the measurement results in typical situations and show under what conditions it can be easily taken into account and does not hinder, but rather helps, in characterization of collagen fiber alignment.

  7. Mesoscopic biology

    Indian Academy of Sciences (India)

    G V Shivashankar

    2002-02-01

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological systems. In recent years advances in technology have led to the study of some of the design principles of these machines; in particular at the level of an individual molecule. For example, the forces that operate in molecular interactions, the stochasticity involved in these interactions and their spatio-temporal dynamics are beginning to be explored. Understanding such design principles is opening new possibilities in mesoscopic physics with potential applications.

  8. Snow thickness retrieval over thick Arctic sea ice using SMOS satellite data

    Science.gov (United States)

    Maaß, N.; Kaleschke, L.; Tian-Kunze, X.; Drusch, M.

    2013-12-01

    The microwave interferometric radiometer of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission measures at a frequency of 1.4 GHz in the L-band. In contrast to other microwave satellites, low frequency measurements in L-band have a large penetration depth in sea ice and thus contain information on the ice thickness. Previous ice thickness retrievals have neglected a snow layer on top of the ice. Here, we implement a snow layer in our emission model and investigate how snow influences L-band brightness temperatures and whether it is possible to retrieve snow thickness over thick Arctic sea ice from SMOS data. We find that the brightness temperatures above snow-covered sea ice are higher than above bare sea ice and that horizontal polarisation is more affected by the snow layer than vertical polarisation. In accordance with our theoretical investigations, the root mean square deviation between simulated and observed horizontally polarised brightness temperatures decreases from 20.9 K to 4.7 K, when we include the snow layer in the simulations. Although dry snow is almost transparent in L-band, we find brightness temperatures to increase with increasing snow thickness under cold Arctic conditions. The brightness temperatures' dependence on snow thickness can be explained by the thermal insulation of snow and its dependence on the snow layer thickness. This temperature effect allows us to retrieve snow thickness over thick sea ice. For the best simulation scenario and snow thicknesses up to 35 cm, the average snow thickness retrieved from horizontally polarised SMOS brightness temperatures agrees within 0.1 cm with the average snow thickness measured during the IceBridge flight campaign in the Arctic in spring 2012. The corresponding root mean square deviation is 5.5 cm, and the coefficient of determination is r2 = 0.58.

  9. Breakup of finite thickness viscous shell microbubbles by ultrasound: A simplified zero-thickness shell model

    OpenAIRE

    HSIAO, Chao-Tsung; Chahine, Georges L.

    2013-01-01

    A simplified three-dimensional (3-D) zero-thickness shell model was developed to recover the non-spherical response of thick-shelled encapsulated microbubbles subjected to ultrasound excitation. The model was validated by comparison with previously developed models and was then used to study the mechanism of bubble break-up during non-spherical deformations resulting from the presence of a nearby rigid boundary. The effects of the shell thickness and the bubble standoff distanc...

  10. Snow thickness retrieval over thick Arctic sea ice using SMOS satellite data

    Directory of Open Access Journals (Sweden)

    N. Maaß

    2013-12-01

    Full Text Available The microwave interferometric radiometer of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS mission measures at a frequency of 1.4 GHz in the L-band. In contrast to other microwave satellites, low frequency measurements in L-band have a large penetration depth in sea ice and thus contain information on the ice thickness. Previous ice thickness retrievals have neglected a snow layer on top of the ice. Here, we implement a snow layer in our emission model and investigate how snow influences L-band brightness temperatures and whether it is possible to retrieve snow thickness over thick Arctic sea ice from SMOS data. We find that the brightness temperatures above snow-covered sea ice are higher than above bare sea ice and that horizontal polarisation is more affected by the snow layer than vertical polarisation. In accordance with our theoretical investigations, the root mean square deviation between simulated and observed horizontally polarised brightness temperatures decreases from 20.9 K to 4.7 K, when we include the snow layer in the simulations. Although dry snow is almost transparent in L-band, we find brightness temperatures to increase with increasing snow thickness under cold Arctic conditions. The brightness temperatures' dependence on snow thickness can be explained by the thermal insulation of snow and its dependence on the snow layer thickness. This temperature effect allows us to retrieve snow thickness over thick sea ice. For the best simulation scenario and snow thicknesses up to 35 cm, the average snow thickness retrieved from horizontally polarised SMOS brightness temperatures agrees within 0.1 cm with the average snow thickness measured during the IceBridge flight campaign in the Arctic in spring 2012. The corresponding root mean square deviation is 5.5 cm, and the coefficient of determination is r2 = 0.58.

  11. Crusts: biological

    Science.gov (United States)

    Belnap, Jayne; Elias, Scott A.

    2013-01-01

    Biological soil crusts, a community of cyanobacteria, lichens, mosses, and fungi, are an essential part of dryland ecosystems. They are critical in the stabilization of soils, protecting them from wind and water erosion. Similarly, these soil surface communities also stabilized soils on early Earth, allowing vascular plants to establish. They contribute nitrogen and carbon to otherwise relatively infertile dryland soils, and have a strong influence on hydrologic cycles. Their presence can also influence vascular plant establishment and nutrition.

  12. Biological programming

    OpenAIRE

    Ramsden, Jeremy J.; Bándi, Gergely

    2010-01-01

    Biology offers a tremendous set of concepts that are potentially very powerfully usable for the software engineer, but they have been barely exploited hitherto. In this position paper we propose a fresh attempt to create the building blocks of a programming technology that could be as successful as life. A key guiding principle is to develop and make use of unambiguous definitions of the essential features of life.

  13. Martian lithospheric thickness from elastic flexure theory

    Science.gov (United States)

    Thurber, C. H.; Toksoz, M. N.

    1978-01-01

    The thickness of the elastic lithosphere in the Tharsis region of Mars is estimated from effects due to the surface load of Olympus Mons. Deformation (vertical displacement) and stress are calculated using elastic flexure theory for a range of possible lithospheric thicknesses (T), modeling the lithosphere as a thin elastic shell and the interior as a Newtonian fluid. For T below 150 km, displacement and stress rise rapidly with decreasing thickness. For T near 100 km, deformation of the region surrounding the volcano would be clearly visible in the topography, and resulting tensional stresses exceeding 5 kbar should produce observable fracturing at the surface. In contrast, for T near 200 km deformation is minimal and the tensional stress, being less than a kilobar, would not result in extensive fracturing. Since significant deformation and fracturing are not observed, it is concluded that the Martian elastic lithosphere is at least 150 km in thickness. Seismic, tectonic, and gravity observations all suggest a thick Martian lithosphere as well.

  14. Uncertainty estimation of ultrasonic thickness measurement

    International Nuclear Information System (INIS)

    The most important factor that should be taken into consideration when selecting ultrasonic thickness measurement technique is its reliability. Only when the uncertainty of a measurement results is known, it may be judged if the result is adequate for intended purpose. The objective of this study is to model the ultrasonic thickness measurement function, to identify the most contributing input uncertainty components, and to estimate the uncertainty of the ultrasonic thickness measurement results. We assumed that there are five error sources significantly contribute to the final error, these sources are calibration velocity, transit time, zero offset, measurement repeatability and resolution, by applying the propagation of uncertainty law to the model function, a combined uncertainty of the ultrasonic thickness measurement was obtained. In this study the modeling function of ultrasonic thickness measurement was derived. By using this model the estimation of the uncertainty of the final output result was found to be reliable. It was also found that the most contributing input uncertainty components are calibration velocity, transit time linearity and zero offset. (author)

  15. Marine biology

    International Nuclear Information System (INIS)

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  16. Marine biology

    Energy Technology Data Exchange (ETDEWEB)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.

  17. Study on Folds of Equal Thickness Multi-layer Sandwiched in Different Thickness Media

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The theoretical model and non-homogeneous differential equation of equal thickness multi-layer folds sandwiched in different thickness and same character media are established by elastic and plastic mechanics. The special answer of the non-homogeneous differential equation and the common answer of the homogeneous differential equation are deduced by applying logistic equation and special function, and the dominant wavelength theory of equal thickness multi-layer folds sandwiched in different thickness and same character media. In addition, the experimental folding in both elastic and sticky materials proves the dominant wavelength theory.

  18. Black hole feedback from thick accretion discs

    CERN Document Server

    Sadowski, Aleksander; Abramowicz, Marek A; Narayan, Ramesh

    2015-01-01

    We study energy flows in geometrically thick accretion discs, both optically thick and thin, using general relativistic, three-dimensional simulations of black hole accretion flows. We find that for non-rotating black holes the efficiency of the total feedback from thick accretion discs is $3\\%$ - roughly half of the thin disc efficiency. This amount of energy is ultimately distributed between outflow and radiation, the latter scaling weakly with the accretion rate for super-critical accretion rates, and returned to the interstellar medium. Accretion on to rotating black holes is more efficient because of the additional extraction of rotational energy. However, the jet component is collimated and likely to interact only weakly with the environment, whereas the outflow and radiation components cover a wide solid angle.

  19. Theory of the sea ice thickness distribution

    CERN Document Server

    Toppaladoddi, Srikanth

    2015-01-01

    We use concepts from statistical physics to transform the original evolution equation for the sea ice thickness distribution $g(h)$ due to Thorndike et al., (1975) into a Fokker-Planck like conservation law. The steady solution is $g(h) = {\\cal N}(q) h^q \\mathrm{e}^{-~ h/H}$, where $q$ and $H$ are expressible in terms of moments over the transition probabilities between thickness categories. The solution exhibits the functional form used in observational fits and shows that for $h \\ll 1$, $g(h)$ is controlled by both thermodynamics and mechanics, whereas for $h \\gg 1$ only mechanics controls $g(h)$. Finally, we derive the underlying Langevin equation governing the dynamics of the ice thickness $h$, from which we predict the observed $g(h)$. The genericity of our approach provides a framework for studying the geophysical scale structure of the ice pack using methods of broad relevance in statistical mechanics.

  20. Theory of the Sea Ice Thickness Distribution.

    Science.gov (United States)

    Toppaladoddi, Srikanth; Wettlaufer, J S

    2015-10-01

    We use concepts from statistical physics to transform the original evolution equation for the sea ice thickness distribution g(h) from Thorndike et al. into a Fokker-Planck-like conservation law. The steady solution is g(h)=N(q)h(q)e(-h/H), where q and H are expressible in terms of moments over the transition probabilities between thickness categories. The solution exhibits the functional form used in observational fits and shows that for h≪1, g(h) is controlled by both thermodynamics and mechanics, whereas for h≫1 only mechanics controls g(h). Finally, we derive the underlying Langevin equation governing the dynamics of the ice thickness h, from which we predict the observed g(h). The genericity of our approach provides a framework for studying the geophysical-scale structure of the ice pack using methods of broad relevance in statistical mechanics. PMID:26551827

  1. Thickness diffusivity in the Southern Ocean

    Science.gov (United States)

    Eden, Carsten

    2006-06-01

    Thickness diffusivity ($\\kappa$) according to the Gent and McWilliams parameterisation which accounts for eddy-driven advection in the ocean, is estimated using output from an eddy-resolving model of the Southern Ocean. A physically meaningful definition of rotational eddy fluxes leads almost everywhere to positive $\\kappa$. Zonally averaged near surface values of $\\kappa$ remain smaller than 200 m2/s poleward of the polar front, increases between 60-45°S to about 600 m2/s and peak between 45-35° S at almost 3000 m2/s. $\\kappa$ stays high in the upper 500 m but decreases with depth and is essentially zero below 2500 m. In addition to the thickness diffusion ($\\kappa$) there is eddy-induced eastward (westward) advection of isopycnal thickness at the poleward (equatorward) flank of the ACC pointing toward strong anisotropic lateral mixing.

  2. Fast neutron spectrometry using thick threshold detectors

    OpenAIRE

    Idiri Z.; Allab M.; Boukeffoussa K.; Medkour Ishak-Boushaki G.

    2012-01-01

    This paper discusses the use of thick threshold activation detectors for the characterization of low intensity neutron fields. This technique has been applied to the determination of the spectral emission of a low activity (37 GBq) Am-Be source. The reaction rates induced by the neutrons emitted by this source in different thick metallic targets (Al, Si, Fe, In) have been measured in the following reactions: 27Al(n,p)27Mg, 27Al(n,α)24Na, 28Si(n,p)28Al, 56Fe(n,p)56Mn, 115In(n, n′)115mIn and 11...

  3. Nuclear symmetry energy and neutron skin thickness

    CERN Document Server

    Warda, M; Viñas, X; Roca-Maza, X

    2012-01-01

    The relation between the slope of the nuclear symmetry energy at saturation density and the neutron skin thickness is investigated. Constraints on the slope of the symmetry energy are deduced from the neutron skin data obtained in experiments with antiprotonic atoms. Two types of neutron skin are distinguished: the "surface" and the "bulk". A combination of both types forms neutron skin in most of nuclei. A prescription to calculate neutron skin thickness and the slope of symmetry energy parameter $L$ from the parity violating asymmetry measured in the PREX experiment is proposed.

  4. Hot rolling of thick uranium molybdenum alloys

    Science.gov (United States)

    DeMint, Amy L.; Gooch, Jack G.

    2015-11-17

    Disclosed herein are processes for hot rolling billets of uranium that have been alloyed with about ten weight percent molybdenum to produce cold-rollable sheets that are about one hundred mils thick. In certain embodiments, the billets have a thickness of about 7/8 inch or greater. Disclosed processes typically involve a rolling schedule that includes a light rolling pass and at least one medium rolling pass. Processes may also include reheating the rolling stock and using one or more heavy rolling passes, and may include an annealing step.

  5. Electromagnetic imaging through thick metallic enclosures

    Directory of Open Access Journals (Sweden)

    Brendan J. Darrer

    2015-08-01

    Full Text Available The ability to image through metallic enclosures is an important goal of any scanning technology for security applications. Previous work demonstrated the penetrating power of electromagnetic imaging through thin metallic enclosures, thus validating the technique for security applications such as cargo screening. In this work we study the limits of electromagnetic imaging through metallic enclosures, considering the performance of the imaging for different thicknesses of the enclosure. Our results show, that our system can image a Copper disk, even when enclosed within a 20 mm thick Aluminum box. The potential for imaging through enclosures of other materials, such as Lead, Copper, and Iron, is discussed.

  6. Glue Film Thickness Measurements by Spectral Reflectance

    International Nuclear Information System (INIS)

    Spectral reflectance was used to determine the thickness of thin glue layers in a study of the effect of the glue on radiance and reflectance measurements of shocked-tin substrates attached to lithium fluoride windows. Measurements based on profilometry of the components were found to be inaccurate due to flatness variations and deformation of the tin substrate under pressure during the gluing process. The accuracy of the spectral reflectance measurements were estimated to be ±0.5 (micro)m, which was sufficient to demonstrate a convincing correlation between glue thickness and shock-generated light.

  7. Diurnal variations in human corneal thickness.

    OpenAIRE

    Harper, C L; Boulton, M. E.; Bennett, D.; Marcyniuk, B; Jarvis-Evans, J H; Tullo, A. B.; Ridgway, A E

    1996-01-01

    AIM: To elucidate the diurnal variation in human corneal thickness over a 48 hour period. METHOD: Changes in central corneal thickness were monitored in eight healthy subjects (four male, four female) aged between 10 and 63 years using an ultrasonic pachymeter. Measurements were made over a 48 hour period-immediately before sleep, immediately upon waking and at 15, 30, 45 minutes, 1, 1.5, 2, 2.5, 3 hours, and at 2 hour intervals thereafter throughout the remainder of each day. RESULTS: The me...

  8. Pulsar Wind Nebulae with Thick Toroidal Structure

    OpenAIRE

    Chevalier, Roger A.; Reynolds, Stephen P.

    2011-01-01

    We investigate a class of pulsar wind nebulae that show synchrotron emission from a thick toroidal structure. The best studied such object is the small radio and X-ray nebula around the Vela pulsar, which can be interpreted as the result of interaction of a mildly supersonic inward flow with the recent pulsar wind. Such a flow near the center of a supernova remnant can be produced in a transient phase when the reverse shock reaches the center of the remnant. Other nebulae with a thick toroida...

  9. Matrix effects in PIXE elemental analysis of thick calculi targets

    Science.gov (United States)

    Kwiatek, Wojciech M.; Lekki, Janusz; Nowak, Tomasz; Dutkiewicz, Erazm M.; Paluszkiewicz, Czeslawa

    1997-02-01

    The PIXE technique for Trace Element Analysis have been applied to the studies of mineral deposits such as kidney stones in human organism. The calculi mainly composed of phosphates, oxalates and uric acid were extracted during surgical operations and were measured at the proton beam as thick targets. Trace elements studies of such samples are influenced by the thick targets matrix effects and by the sample composition changes caused by energy deposition in the target due to the proton beam irradiation. These both difficulties are especially pronounced in the case of the biological samples. In this paper the procedure dealing with the above problems is described, basing on calculations with the use of principal formula for the detected X-ray yields and two complementary techniques for PIXE experiments such as Fourier Transform InfraRed Spectroscopy (FTIR) and Elastic Back Scattering (EBS). A rough estimation of sample chemical composition was achieved by means of the FTIR analysis, which also may serve as a tool for local sample temperature estimation during beam irradiation. Composition of major target elements, needed for beam stopping and X-rays attenuation calculations were determined using the EBS technique applied simultaneously with PIXE. The above approach was used to estimate elemental contents of several samples. Comparison between traditionally calculated and improved results is presented.

  10. Partial-thickness corneal tissue restoration after a chemical burn

    Directory of Open Access Journals (Sweden)

    Galan A

    2016-04-01

    Full Text Available Alessandro Galan, Anton Giulio Catania, Giuseppe Lo Giudice San Paolo Ophthalmic Center, San Antonio Hospital, Padova, Italy Purpose: We describe a case of full-thickness corneal restoration after an acute corneal burn with an acid agent. Methods: A 32-year-old male reported painful discomfort, redness, photophobia, and a decrease in visual acuity in the left eye after a unilateral burn with an acid agent. Slit-lamp examination revealed massive corneal melting involving necrotic sequestrum of the entire corneal surface. Surgical approach was carried out in order to preserve residual ocular tissues. Results: Extensive corneal–conjunctival layer curettage of the necrotic tissue was performed showing perfectly clear undamaged deep lamellar corneal layers. The patient underwent multilayered amniotic membrane transplantation and total capsular–conjunctival flap in order to preserve ocular tissue from further melting or corneal perforation. A complete and spontaneous “restitutio ad integrum” of the corneal layers was shown during the follow-up. The cornea was perfectly clear with restored normal anatomical architecture. Conclusion: In this case, a spontaneous full-thickness corneal tissue restoration occurred after an acute chemical burn. Studies about the mechanisms whereby different cells interact and replicate within the stroma may unveil the biology behind corneal regeneration and transparency. Keywords: amniotic membrane, chemical burn, corneal healing

  11. Biological Databases

    Directory of Open Access Journals (Sweden)

    Kaviena Baskaran

    2013-12-01

    Full Text Available Biology has entered a new era in distributing information based on database and this collection of database become primary in publishing information. This data publishing is done through Internet Gopher where information resources easy and affordable offered by powerful research tools. The more important thing now is the development of high quality and professionally operated electronic data publishing sites. To enhance the service and appropriate editorial and policies for electronic data publishing has been established and editors of article shoulder the responsibility.

  12. Through-thickness inhomogeneity of localized corrosion in 7050-T7451 Al alloy thick plate

    Institute of Scientific and Technical Information of China (English)

    丰雷; 潘清林; 韦莉莉; 黄志其; 刘志铭

    2015-01-01

    The through-thickness corrosion inhomogeneity of 7050-T7451 Al alloy thick plate was studied using immersion tests, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), slow strain rate testing (SSRT) technique combined with optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the through-thickness corrosion resistance is ranked in the order of T/2>surface>T/4. And the 75 mm-thick 7050 alloy plate presents better corrosion resistance than the 35 mm-thick plate. The results are discussed in terms of the combined effect of recrystallization and cooling rate in quenching. Alloy with lower volume fraction of recrystallization and smaller grain aspect ratio displays better corrosion resistance. The lower corrosion resistance caused by the slower cooling rate results from the higher coverage rate of grain boundary precipitates and larger width of precipitate free zone.

  13. Percolation effect in thick film superconductors

    International Nuclear Information System (INIS)

    A thick film superconductor paste has been developed to study the properties of granulated superconductor materials, to observe the percolation effect and to confirm the theory of the conducting mechanism in the superconducting thick films. This paste was also applied to make a superconducting planar transformer. Due to high Tc and advantageous current density properties the base of the paste was chosen to be of Bi(Pb)SrCaCuO system. For contacts a conventional Ag/Pt paste was used. The critical temperature of the samples were between 110 K and 115 K depending on the printed layer thickness. The critical current density at the boiling temperature of the liquid He- was between 200-300 A/cm2. The R(T) and V(I) functions were measured with different parameters. The results of the measurements have confirmed the theory of conducting mechanism in the material. The percolation structure model has been built and described. As an application, a superconducting planar thick film transformer was planned and produced. Ten windings of the transformer were printed on one side of the alumina substrate and one winding was printed on the other side. The coupling between the two sides was possible through the substrate. The samples did not need special drying and firing parameters. After the preparation, the properties of the transformer were measured. The efficiency and the losses were determined. Finally, some fundamental advantages and problems of the process were discussed

  14. Thick Slice and Thin Slice Teaching Evaluations

    Science.gov (United States)

    Tom, Gail; Tong, Stephanie Tom; Hesse, Charles

    2010-01-01

    Student-based teaching evaluations are an integral component to institutions of higher education. Previous work on student-based teaching evaluations suggest that evaluations of instructors based upon "thin slice" 30-s video clips of them in the classroom correlate strongly with their end of the term "thick slice" student evaluations. This study's…

  15. Changes of epidermal thickness in vitiligo.

    Science.gov (United States)

    Jung, Soo-Eun; Kang, Hee Young; Lee, Eun-So; Kim, You Chan

    2015-04-01

    The stratum corneum and epidermal pigmentation have protective roles against ultraviolet radiation. Because vitiligo skin lacks melanocytes and has no potential to produce pigment, some studies suggested that the epidermis in vitiligo skin is thicker than in normal skin. However, only a few studies investigated epidermal thickness changes in vitiligo, and some of these had relatively small sample sizes. Thus, this study aimed to compare epidermal thickness between vitiligo skin and adjacent normal-appearing skin in a large cohort. Photos of hematoxylin and eosin–stained slides of vitiligo skin and adjacent normal-appearing skin were taken under a microscope. The thicknesses of the stratum corneum, viable epidermis, and full epidermis were then measured by a computerized image analyzer. A total of 206 patients (412 sections) were included. There were significant differences between vitiligo skin and adjacent normal-appearing skin in the thickness of the stratum corneum (P = 0.009), viable epidermis (P = 0.001), and total epidermis (P = 0.001). An analysis comparing skin biopsied from a sun-exposed area versus a sun-protected area showed that the stratum corneum, viable epidermis, and total epidermis were significantly thicker in vitiligo skin than in normal-appearing skin in sun-exposed areas (P vitiligo skin than in normal-appearing skin, especially on sun-exposed skin, and that this may represent a photoprotective role compensating for absent pigmentation.

  16. Heat Transfer in the Thick Thermoset Composites

    NARCIS (Netherlands)

    Shi, L.

    2016-01-01

    Nowadays more and more large composites are used to replace the traditional metallic structural materials in the industries. However, for manufacturing the thick thermoset composites, the size not only influences the mechanical properties in the completed products, but also the core temperature over

  17. The Diversity of Thick Galactic Discs

    CERN Document Server

    Kasparova, Anastasia V; Chilingarian, Igor V; Silchenko, Olga K; Moiseev, Alexey V; Borisov, Svyatoslav B

    2016-01-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on S0-a disc galaxies located in different environments: NGC4111 in a dense group, NGC4710 in the Virgo cluster, and NGC5422 in a sparse group. We see intermediate age (4-5 Gyr) metal rich ([Fe/H] $\\sim$ -0.2 - 0.0 dex) stellar populations in NGC4111 and NGC4710. On the other hand, NGC5422 does not harbour young stars, its disc is thick and old (10 Gyr), without evidence for a second component, and its $\\alpha$-element abundance suggests a 1.5-2 Gyr long formation epoch implying its formation at high redshift. Our results suggest the diversity of thick disc formation scenarios.

  18. Crustal thickness controlled by plate tectonics

    DEFF Research Database (Denmark)

    Artemieva, Irina M.; Meissner, Rolf

    2012-01-01

    /gabbro–eclogite phase transition in crustal evolution and the links between lithosphere recycling, mafic magmatism, and crustal underplating. We advocate that plate tectonics processes, togetherwith basalt/gabbro–eclogite transition, limit crustal thickness worldwide by providing effective mechanisms of crustal...

  19. The diversity of thick galactic discs

    Science.gov (United States)

    Kasparova, Anastasia V.; Katkov, Ivan Yu.; Chilingarian, Igor V.; Silchenko, Olga K.; Moiseev, Alexey V.; Borisov, Svyatoslav B.

    2016-07-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on S0-a disc galaxies located in different environments: NGC 4111 in a dense group, NGC 4710 in the Virgo cluster, and NGC 5422 in a sparse group. We see intermediate age (4-5 Gyr) metal rich ([Fe/H] ˜- 0.2…0.0 dex) stellar populations in NGC 4111 and NGC 4710. On the other hand, NGC 5422 does not harbour young stars, its disc is thick and old (10 Gyr), without evidence for a second component, and its α-element abundance suggests a 1.5-2 Gyr long formation epoch implying its formation at high redshift. Our results suggest the diversity of thick disc formation scenarios.

  20. Thick tool steel coatings with laser cladding

    NARCIS (Netherlands)

    Ocelik, V.; de Oliveira, U.; De Hosson, J. Th. M.; DeHosson, JTM; Brebbia, CA; Nishida, SI

    2007-01-01

    This paper concentrates on thick and crack-free laser clad coatings (up to 3 mm). The coating material is a chromium-molybdenum-tungsten-vanadium alloyed high-speed steel that shows high wear resistance, high compressive strength, good toughness, very good dimensional stability on heat treatment and

  1. Percolation effect in thick film superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Sali, R.; Harsanyi, G. [Technical Univ. of Budapest (Hungary)

    1994-12-31

    A thick film superconductor paste has been developed to study the properties of granulated superconductor materials, to observe the percolation effect and to confirm the theory of the conducting mechanism in the superconducting thick films. This paste was also applied to make a superconducting planar transformer. Due to high T{sub c} and advantageous current density properties the base of the paste was chosen to be of Bi(Pb)SrCaCuO system. For contacts a conventional Ag/Pt paste was used. The critical temperature of the samples were between 110 K and 115 K depending on the printed layer thickness. The critical current density at the boiling temperature of the liquid He- was between 200-300 A/cm{sup 2}. The R(T) and V(I) functions were measured with different parameters. The results of the measurements have confirmed the theory of conducting mechanism in the material. The percolation structure model has been built and described. As an application, a superconducting planar thick film transformer was planned and produced. Ten windings of the transformer were printed on one side of the alumina substrate and one winding was printed on the other side. The coupling between the two sides was possible through the substrate. The samples did not need special drying and firing parameters. After the preparation, the properties of the transformer were measured. The efficiency and the losses were determined. Finally, some fundamental advantages and problems of the process were discussed.

  2. Measuring Thicknesses With In Situ Ultrasonic Transducers

    Science.gov (United States)

    Dunn, Daniel E.; Cerino, Joseph R.

    1995-01-01

    Several pulsed ultrasonic transducers attached to workpiece for measurement of changes in thicknesses of workpiece at transducer locations during grinding and polishing, according to proposal. Once attached, each transducer remains attached at original position until all grinding and polishing operations complete. In typical application, workpiece glass or ceramic blank destined to become component of optical system.

  3. Modeling of thickness for semisolid foods

    NARCIS (Netherlands)

    Terpstra, M.E.J.; Janssen, A.M.; Prinz, J.F.; Wijk, R.A. de; Weenen, H.; Linden, E. van der

    2005-01-01

    We investigated the relationship between orally perceived thickness and calculated shear stress on the tongue for mayonnaise and custard. To this end, the applicability of the models of Kokini et al. (1977), describing the mechanical breakdown in the mouth, have been tested. Within a limited range o

  4. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  5. The crustal thickness of West Antarctica

    Science.gov (United States)

    Chaput, J.; Aster, R. C.; Huerta, A.; Sun, X.; Lloyd, A.; Wiens, D.; Nyblade, A.; Anandakrishnan, S.; Winberry, J. P.; Wilson, T.

    2014-01-01

    P-to-S receiver functions (PRFs) from the Polar Earth Observing Network (POLENET) GPS and seismic leg of POLENET spanning West Antarctica and the Transantarctic Mountains deployment of seismographic stations provide new estimates of crustal thickness across West Antarctica, including the West Antarctic Rift System (WARS), Marie Byrd Land (MBL) dome, and the Transantarctic Mountains (TAM) margin. We show that complications arising from ice sheet multiples can be effectively managed and further information concerning low-velocity subglacial sediment thickness may be determined, via top-down utilization of synthetic receiver function models. We combine shallow structure constraints with the response of deeper layers using a regularized Markov chain Monte Carlo methodology to constrain bulk crustal properties. Crustal thickness estimates range from 17.0±4 km at Fishtail Point in the western WARS to 45±5 km at Lonewolf Nunataks in the TAM. Symmetric regions of crustal thinning observed in a transect deployment across the West Antarctic Ice Sheet correlate with deep subice basins, consistent with pure shear crustal necking under past localized extension. Subglacial sediment deposit thicknesses generally correlate with trough/dome expectations, with the thickest inferred subice low-velocity sediment estimated as ˜0.4 km within the Bentley Subglacial Trench. Inverted PRFs from this study and other published crustal estimates are combined with ambient noise surface wave constraints to generate a crustal thickness map for West Antarctica south of 75°S. Observations are consistent with isostatic crustal compensation across the central WARS but indicate significant mantle compensation across the TAM, Ellsworth Block, MBL dome, and eastern and western sectors of thinnest WARS crust, consistent with low density and likely dynamic, low-viscosity high-temperature mantle.

  6. Clinical significance of central corneal thickness and comparison of central corneal thickness

    Directory of Open Access Journals (Sweden)

    Özgür Çakıcı

    2014-03-01

    Full Text Available Significance of central corneal thickness has been increasing in ophthalmology practice. It is an important clinical evaluation tool especially prior to refractive surgery and in diagnosis of glaucoma and keratoconus. Refractive surgery is planned according to preoperative central corneal thickness measurements. Besides, in order to determine actual intraocular pressure, central corneal thickness is measured and corrected eye pressure is obtained. Today, devices used in measurement of central corneal thickness do the measurement according to two principles. First and relatively older method is ultrasonic method. Optic method is the second and more recent method. In daily practice, the most commonly used clinical method in measurement of central corneal thickness is ultrasound pachymeter. However, this measurement technique requires contact between cornea and probe and gives thinner measurement results compared to the methods that use optic principle. Recently, several technologic methods based on optics have been put in use; they provide advantages of non-contact technique and objective determination of central corneal thickness. Of these methods, most commonly used include Specular Microscopy, Optical coherence tomography, Laser Doppler Interferometry, Optical low coherence reflectometry pachymetry, Optic based topographic mapping (also called screening section pachymetry and Pentacam. In this article, it was aimed to evaluate importance of central corneal thickness in clinical use and compare measurement methods. J Clin Exp Invest 2014; 5 (1: 153-158

  7. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  8. Creating biological nanomaterials using synthetic biology

    Directory of Open Access Journals (Sweden)

    MaryJoe K Rice

    2014-01-01

    Full Text Available Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  9. The heterogeneous ice shell thickness of Enceladus

    Science.gov (United States)

    Lucchetti, Alice; Pozzobon, Riccardo; Mazzarini, Francesco; Cremonese, Gabriele; Massironi, Matteo

    2016-10-01

    Saturn's moon Enceladus is the smallest Solar System body that presents an intense geologic activity on its surface. Plumes erupting from Enceladus' South Polar terrain (SPT) provide direct evidence of a reservoir of liquid below the surface. Previous analysis of gravity data determined that the ice shell above the liquid ocean must be 30-40 km thick from the South Pole up to 50° S latitude (Iess et al., 2014), however, understand the global or regional nature of the ocean beneath the ice crust is still challenging. To infer the thickness of the outer ice shell and prove the global extent of the ocean, we used the self-similar clustering method (Bonnet et al., 2001; Bour et al., 2002) to analyze the widespread fractures of the Enceladus's surface. The spatial distribution of fractures has been analyzed in terms of their self-similar clustering and a two-point correlation method was used to measure the fractal dimension of the fractures population (Mazzarini, 2004, 2010). A self-similar clustering of fractures is characterized by a correlation coefficient with a size range defined by a lower and upper cut-off, that represent a mechanical discontinuity and the thickness of the fractured icy crust, thus connected to the liquid reservoir. Hence, this method allowed us to estimate the icy shell thickness values in different regions of Enceladus from SPT up to northern regions.We mapped fractures in ESRI ArcGis environment in different regions of the satellite improving the recently published geological map (Crow-Willard and Pappalardo, 2015). On these regions we have taken into account the fractures, such as wide troughs and narrow troughs, located in well-defined geological units. Firstly, we analyzed the distribution of South Polar Region fracture patterns finding an ice shell thickness of ~ 31 km, in agreement with gravity measurements (Iess et al., 2014). Then, we applied the same approach to other four regions of the satellite inferring an increasing of the ice

  10. Structural Biology Fact Sheet

    Science.gov (United States)

    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  11. Thick brane solitons breaking $Z_2$ symmetry

    CERN Document Server

    Peyravi, Marzieh; Lobo, Francisco S N

    2015-01-01

    New soliton solutions for thick branes in 4 + 1 dimensions are considered in this article. In particular, brane models based on the sine-Gordon (SG), $\\varphi^{4}$ and $\\varphi^{6}$ scalar fields are investigated; in some cases $Z_{2}$ symmetry is broken. Besides, these soliton solutions are responsible for supporting and stabilizing the thick branes. In these models, the origin of the symmetry breaking resides in the fact that the modified scalar field potential may have non-degenerate vacuua and these non-degenerate vacuua determine the cosmological constant on both sides of the brane. At last, in order to explore the particle motion in the neighborhood of the brane, the geodesic equations along the fifth dimension are studied.

  12. Hybrid Optimization for Wind Turbine Thick Airfoils

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, F. [ECN Wind Energy, Petten (Netherlands)

    2012-06-15

    One important element in aerodynamic design of wind turbines is the use of specially tailored airfoils to increase the ratio of energy capture and reduce cost of energy. This work is focused on the design of thick airfoils for wind turbines by using numerical optimization. A hybrid scheme is proposed in which genetic and gradient based algorithms are combined together to improve the accuracy and the reliability of the design. Firstly, the requirements and the constraints for this class of airfoils are described; then, the hybrid approach is presented. The final part of this work is dedicated to illustrate a numerical example regarding the design of a new thick airfoil. The results are discussed and compared to existing airfoils.

  13. A new probe of neutron skin thickness

    Institute of Scientific and Technical Information of China (English)

    SUN Xiao-Yan; ZHOU Pei; FANG De-Qing; MA Yu-Gang; CAI Xiang-Zhou; CHEN Jin-Gen; GUO Wei; TIAN Wen-Dong; WANG Hong-Wei; ZHANG Guo-Qiang

    2011-01-01

    The correlation between neutron-to-proton yield ratio (R) and neutron skin thickness (δ) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics (IQMD) model. The density distribution of the Droplet model is embedded in the initialization of the neutron and proton densities in the present IQMD model. By adjusting the diffuseness parameter of neutron density in the Droplet model for the projectile, the relationship between the neutron skin thickness and the corresponding R is obtained. The results show strong linear correlation between R and δ for neutron-rich Ca and Ni isotopes. It is suggested that R may be used as an experimental observable to extract δ for neutron-rich nuclei, which is very interesting in the study of the nuclear structure of exotic nuclei, the equation of state (EOS) of asymmetric nuclear matter and neutron-rich matter in astrophysics, etc.

  14. Neutron skin thickness and nuclear matter properties

    Science.gov (United States)

    Yoshida, S.; Sagawa, H.

    2007-08-01

    Linear correlations are found among the isovector nuclear matter properties in both the Skyrme-Hartree-Fock (SHF) and the relativistic mean-field (RMF) models. In addition, we found a kind of correlation between the isovector nuclear matter properties and the incompressibility in the SHF model. The Skyrme parameters are related analytically to nuclear matter properties with the Thomas—Fermi approximation. By using a linear correlation between the neutron skin thickness and the pressure of the neutron matter in the SHF model, we show that the neutron skin thickness of 208Pb gives crucial information about not only the neutron equation of state but also the isovector nuclear matter properties and the parametrization of Skyrme interaction.

  15. Compressive strength of thick composite panels

    DEFF Research Database (Denmark)

    Branner, Kim; Berring, Peter

    2011-01-01

    The aim of this study is to investigate how much the compressive strength of thick composite panels is reduced due to delaminations and to investigate under which conditions a delamination will grow. Understanding of this is essential in order to move forward the design limits used in the structu......The aim of this study is to investigate how much the compressive strength of thick composite panels is reduced due to delaminations and to investigate under which conditions a delamination will grow. Understanding of this is essential in order to move forward the design limits used...... in the structural design process. Results obtained from finite element modeling analyses are compared with an experimental test campaign performed on flat composite panels with and without delaminations....

  16. Thick composite structures under a load pinch

    OpenAIRE

    Karama, Moussa

    2015-01-01

    Thick composites are increasingly used in the design of mechanical structures. Combined with low weight, they are generally resistant structures, which can support importante loads. In addition, depending on the number and nature of the materials used, it is possible to adapt properties for specific applications (damping structures).This work proposes the establishment of a new theoretical model of multilayer beam. The model, which is simple and easy handling, is intended for the subsequent e...

  17. Thick brane world model from perfect fluid

    CERN Document Server

    Ivashchuk, V D

    2001-01-01

    A (1 + d)-dimensional thick "brane world" model with varying Lambda-term is considered. The model is generalized to the case of a chain of Ricci-flat internal spaces when the matter source is an anisotropic perfect fluid. The "horizontal" part of potential is obtained in the Newtonian approximation. In the multitemporal case (with a Lambda-term) a set of equations for potentials is presented.

  18. The normal choroidal thickness in southern Thailand

    OpenAIRE

    Jirarattanasopa P; Panon N; Hiranyachattada S; Bhurayanontachai P

    2014-01-01

    Pichai Jirarattanasopa,1 Nisa Panon,2 Siriphun Hiranyachattada,2 Patama Bhurayanontachai1 1Department of Ophthalmology, Faculty of Medicine, 2Department of Physiology, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand Objective: To investigate the association between subfoveal choroidal thickness in healthy southern Thailand volunteers and age, axial length, and refractive error.Subjects and methods: This was a prospective cross-sectional case series. A total of 210&n...

  19. The normal choroidal thickness in southern Thailand

    OpenAIRE

    Jirarattanasopa, Pichai

    2014-01-01

    Pichai Jirarattanasopa,1 Nisa Panon,2 Siriphun Hiranyachattada,2 Patama Bhurayanontachai1 1Department of Ophthalmology, Faculty of Medicine, 2Department of Physiology, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand Objective: To investigate the association between subfoveal choroidal thickness in healthy southern Thailand volunteers and age, axial length, and refractive error.Subjects and methods: This was a prospective cross-sectional case series. A total of 2...

  20. Bounded cascade clouds: albedo and effective thickness

    OpenAIRE

    Cahalan, R. F.

    2002-01-01

    If climate models produced clouds having liquid water amounts close to those observed, they would compute a mean albedo that is often much too large, due to the treatment of clouds as plane-parallel. An approximate lower-bound for this "plane-parallel albedo bias" may be obtained from a fractal model having a range of optical thicknesses similar to those observed in marine stratocumulus, since they are more nearly plane-parallel than most other cloud types. We review ...

  1. Experience With Polymer Thick Film Technology

    OpenAIRE

    Vesa Sortti; Raimo Hulkkonen; Eero Jarvinen

    1983-01-01

    The paper describes a user's experiences with polymer thick film resistor technology. The characteristics studied are resistance values and their distributing. Parameters affecting these characteristics are the material of the substrate, and the curing of the polymer resistor paste. The test conditions (temperature cycling, dip soldering, high temperature storaging) were chosen to simulate the environmental conditions, through which the polymer resistor circuits have to go during the assembly...

  2. 30 CFR 816.105 - Backfilling and grading: Thick overburden.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Backfilling and grading: Thick overburden. 816...-SURFACE MINING ACTIVITIES § 816.105 Backfilling and grading: Thick overburden. (a) Definition. Thick... surrounding terrain. (b) Performance standards. Where thick overburden occurs within the permit area,...

  3. Thickness ratio and d 33 effects on flexible piezoelectric unimorph energy conversion

    Science.gov (United States)

    Ha, Taewoo; Zhang, John X. J.; Lu, Nanshu

    2016-03-01

    Piezoelectric unimorphs are bilayer structures where a blanket piezoelectric film (with top and bottom electrodes) is uniformly laminated on an inactive but flexible substrate. Because of their simple construction and flexibility, unimorphs are widely used as a key element in flexible sensors and actuators. The response of a unimorph is governed by the material properties of the film and the substrate as well as their geometric parameters. For low frequency biological energy harvesting, structural optimization is critical due to the dimensional confinement imposed by curvilinear and deformable bio-tissues. Here we report a comprehensive theoretical framework to investigate the effects of the film-to-substrate thickness ratio on voltage, charge, and energy outputs when the unimorph is subjected to eight different boundary/loading conditions. A broad class of power generators can be designed using such a framework under the assumption that the unimorph length is very large compared to its thickness, where the only dimensionless variable is the film-to-substrate thickness ratio. We show that the analytical and finite element modeling results are in excellent agreement. For not so thin unimorphs, there is non-zero normal stress in the thickness direction (σ 3) and d 33 can play a significant role in this case. Non-monotonic dependence of voltage and energy generation on thickness ratio has been found in some cases and optimum thickness ratio for unimorph generator can be predicted. When the unimorph is actuated by voltage applied across the piezo-film thickness, non-monotonic maximum deflection versus thickness ratio is also found. This work provides new physical insights on unimorphs and analytical solutions that can be used for the structural design and optimization of unimorphs under different boundary/loading conditions.

  4. Optically-thick accretion discs with advection

    Institute of Scientific and Technical Information of China (English)

    陈林红; 吴枚; 尚仁成

    2002-01-01

    The structures of optically-thick accretion discs with radial advection have been investigated by the iteration and integration algorithms. The advective cooling term changes mostly the inner part of disc solution, and even results in an optically-thick advection-dominated accretion flow (ADAF). Three distinct branches-the outer Shakura-Sunyaev disc (SSD), the inner ADAF and the middle transition layer-are found for a super-Eddington disc. The SSD-ADAF transition radius can be estimated as 18(M/ME)RG where RG is the Schwarzschild radius, M is the mass accretion rate and ME is the Eddington accretion rate. SSD solutions calculated with the iteration and integration methods are identical, while ADAF solutions obtained by these two methods differ greatly. Detailed algorithms and their differences have been analysed. The iteration algorithm is not self-consistent, since it implies that the dimensionless advection factor ξ is invariant, but in the inner ADAF region the variation of ξ is not negligible. The integration algorithm is always effective for the whole region of an optically-thick disc if the accretion rate is no smaller than 10-4ME. For optically-thin discs, the validity of these two algorithms is different. We suggest that the integration method be employed to calculate the global solution of a disc model without assuming ξ to be a constant. We also discuss its application to the emergent continuum spectrum in order to explain observational facts.

  5. Decreased central corneal thickness in ankylosing spondylitis.

    Science.gov (United States)

    Ortak, Huseyin; Inanır, Ahmet; Demir, Selim; Uysal, Alper; Şahin, Şafak; Sağcan, Mustafa; Önder, Yalçın; Alim, Sait; Demir, Ayşe Kevser

    2014-04-01

    Central corneal thickness and dry eye tests were evaluated in a study population consisting of 68 ankylosing spondylitis patients diagnosed according to the modified New York criteria, and 61 age-matched controls without ankylosing spondylitis. A full ophthalmological evaluation was performed on each subject. All subjects were screened for age, gender, HLA-B27, tear break-up time test, Schirmer test, and duration of disease. Central corneal thickness was measured under topical anesthesia with an ultrasonic pachymeter. The mean central corneal thickness was 537.3 ± 30.6 μm, range 462-600 μm, in ankylosing spondylitis patients, whereas it was 551.7 ± 25.2 μm, range 510-620 μm, in controls (p = 0.005). The Schirmer test result was 7.3 ± 5.9 mm for the ankylosing spondylitis patients and 11.7 ± 5.8 mm for the control group (p = 0.002). Tear break-up time was 7.3 ± 3.2 s for the ankylosing spondylitis patients and 14.0 ± 4.5 s for the control group (p ankylosing spondylitis. In addition, attention must be given to lower dry eye tests in surgical interventions such as photorefractive keratectomy and laser in situ keratomileusis in ankylosing spondylitis patients.

  6. Nano-Hydroxyapatite Thick Film Gas Sensors

    Science.gov (United States)

    Khairnar, Rajendra S.; Mene, Ravindra U.; Munde, Shivaji G.; Mahabole, Megha P.

    2011-12-01

    In the present work pure and metal ions (Co and Fe) doped hydroxyapatite (HAp) thick films have been successfully utilized to improve the structural, morphological and gas sensing properties. Nanocrystalline HAp powder is synthesized by wet chemical precipitation route, and ion exchange process is employed for addition of Co and Fe ions in HAp matrix. Moreover, swift heavy ion irradiation (SHI) technique is used to modify the surface of pure and metal ion exchanged HAp with various ion fluence. The structural investigation of pure and metal ion exchanged HAp thick films are carried out using X-ray diffraction and the presence of functional group is observed by means FTIR spectroscopy. Furthermore, surface morphology is visualized by means of SEM and AFM analysis. CO gas sensing study is carried out for, pure and metal ions doped, HAp thick films with detail investigation on operating temperature, response/recovery time and gas uptake capacity. The surface modifications of sensor matrix by SHI enhance the gas response, response/recovery and gas uptake capacity. The significant observation is here to note that, addition of Co and Fe in HAp matrix and surface modification by SHI improves the sensing properties of HAp films drastically resulting in gas sensing at relatively lower temperatures.

  7. Nano-Hydroxyapatite Thick Film Gas Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Khairnar, Rajendra S.; Mene, Ravindra U.; Munde, Shivaji G.; Mahabole, Megha P. [School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606 (India)

    2011-12-10

    In the present work pure and metal ions (Co and Fe) doped hydroxyapatite (HAp) thick films have been successfully utilized to improve the structural, morphological and gas sensing properties. Nanocrystalline HAp powder is synthesized by wet chemical precipitation route, and ion exchange process is employed for addition of Co and Fe ions in HAp matrix. Moreover, swift heavy ion irradiation (SHI) technique is used to modify the surface of pure and metal ion exchanged HAp with various ion fluence. The structural investigation of pure and metal ion exchanged HAp thick films are carried out using X-ray diffraction and the presence of functional group is observed by means FTIR spectroscopy. Furthermore, surface morphology is visualized by means of SEM and AFM analysis. CO gas sensing study is carried out for, pure and metal ions doped, HAp thick films with detail investigation on operating temperature, response/recovery time and gas uptake capacity. The surface modifications of sensor matrix by SHI enhance the gas response, response/recovery and gas uptake capacity. The significant observation is here to note that, addition of Co and Fe in HAp matrix and surface modification by SHI improves the sensing properties of HAp films drastically resulting in gas sensing at relatively lower temperatures.

  8. Thick Brane Worlds Arising From Pure Geometry

    CERN Document Server

    Cardenas, R; Cardenas, Rolando; Quiros, Israel

    2002-01-01

    We study a non-Riemannian modification of 5-dimensional Kaluza-Klein theory. In our proposal the Riemannian structure of the five-dimensional manifold is replaced by a Weyl-integrable one. In this context a 4-dimensional Poincar$\\grave{e}$ invariant solution is studied. A spacetime structure with two thick (smooth) branes separated in the extra dimension arises. The massless graviton is located in one of the thick branes at the origin, meanwhile the matter degrees of freedom are confined to the other brane. Due to the small overlap of the graviton's wave-function with the second thick brane, the model accounts for a resolution of the mass hierarchy problem a la Randall-Sundrum. Although, initially, no assumptions are made about the topology of the extra dimension, the solution found yields an extra space that is effectivelly compact and respects $Z_2$ symmetry. Unlike other models with branes, the spectrum of massive Kaluza-Klein states is quantized and free of tachyonic modes.

  9. Transport of through a Thick Vadose Zone.

    Science.gov (United States)

    Arnaud, Emmanuelle; Best, Anna; Parker, Beth L; Aravena, Ramon; Dunfield, Kari

    2015-09-01

    Livestock manure applications on fields can be a source of contamination in water resources, including groundwater. Although fecal indicators like have often been detected in tile drainage systems, few studies have monitored groundwater at depth after manure treatments, especially at sites with a deep, heterogeneous vadose zone. Our hypothesis was that microbial transport through a thick vadose zone would be limited or nonexistent due to attenuation processes, subsurface thickness, and heterogeneity. This study tested this hypothesis by monitoring concentrations beneath a 12-m-thick vadose zone of coarse, heterogeneous glacial sediments after surface application of liquid swine manure. was detected on all 23 sample dates over the 5-mo period (4 Apr. 2012-13 Aug. 2012), with particularly elevated concentrations 1 wk after application and lasting for 5 wk. Variable low-level concentrations before and after the elevated period suggest remobilization and delayed transport of microorganisms to the water table without additional loadings within the flow field. These findings suggest preferential flow pathways allowing deep infiltration of manure bacteria as well as a continued source of bacteria, with variable retention and travel times, over several months. Preferential flow pathways at this site include soil macropores, depression focused infiltration, and pathways related to subsurface heterogeneity and/or fracture flow through finer-grained diamict beds. Further research is needed to confirm the relative contribution of sources, constrain travel times, and define specific transport pathways. PMID:26436260

  10. NOVA 201 ultrasonic thickness gage (NOVA Gage)

    Science.gov (United States)

    Garecht, Diane

    1990-01-01

    The measurement integrity of the NOVA 201 digital ultrasonic thickness gage (NOVA gage) was demonstrated by comparing the NOVA gage measurements to the thickness gage measurements, and determining the bias and uncertainty of the NOVA gage when measuring redesigned solid rocket motor (RSRM) hardware per engineering test plans (ETP). The NOVA gage was tested by three different operators on steel and aluminum RSRM hardware for wall thickness. The results show that the measurement bias is not consistent. The uncertainty of the bias is caused by the heterogeneous material properties of the RSRM components that influence the time of flight of ultrasonic waves. The measurement uncertainty inherent to the design and operation of the NOVA gage is less in comparison to the uncertainty of the bias. The total measurement uncertainty cannot be substantially reduced by taking more than one measurement. There is no correlation between bias and the surface finish range of this test unless 3-in-One oil is used as a couplant, in which case there appears to be a slight trend. There is no correlation between uncertainty and the surface finish range. The measurement uncertainty of the NOVA gage can be reduced using 3-in-One oil as a couplant.

  11. Shear deformation in thick auxetic plates

    International Nuclear Information System (INIS)

    This paper aims to understand the effect of auxeticity on shear deformation in thick plates. Three models for the shear correction factor of plates as a function of Poisson’s ratio were proposed: an analytical model, a cubic fit model and a modified model. Of these three, the cubic fit model exhibits the best accuracy over the entire range of Poisson’s ratio from −1 to 0.5. The extent of shear deformation is herein investigated using the example of uniformly loaded circular plates. It was found that the maximum deformation of such plates based on Mindlin theory approximates to those according to Kirchhoff theory when the Poisson’s ratio of the plate material is highly negative. When the Poisson’s ratio of the plate material is −1 and the edge of the plate is simply supported, the calculation of the maximum deflection by Mindlin theory simplifies into that by Kirchhoff theory. These results suggest that auxeticity reduces shear deformation in thick plates, permitting the use of classical plate theory for thick plates only if the plate material is highly auxetic. (paper)

  12. Simulating Biological and Non-Biological Motion

    Science.gov (United States)

    Bruzzo, Angela; Gesierich, Benno; Wohlschlager, Andreas

    2008-01-01

    It is widely accepted that the brain processes biological and non-biological movements in distinct neural circuits. Biological motion, in contrast to non-biological motion, refers to active movements of living beings. Aim of our experiment was to investigate the mechanisms underlying mental simulation of these two movement types. Subjects had to…

  13. Biological Literacy in a College Biology Classroom.

    Science.gov (United States)

    Demastes, Sherry; Wandersee, James H.

    1992-01-01

    Examines the proposed definition of biological literacy as the understanding of a small number of pervasive biological principles appropriate to making informed personal and societal decisions. Utilizes the content of a major daily newspaper to adjust biology instruction to focus on this notion of biological literacy. Discusses benefits and…

  14. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  15. Thickness filters for gradient based multi-material and thickness optimization of laminated composite structures

    DEFF Research Database (Denmark)

    Sørensen, Rene; Lund, Erik

    2015-01-01

    This paper presents a new gradient based method for performing discrete material and thickness optimization of laminated composite structures. The novelty in the new method lies in the application of so-called casting constraints, or thickness filters in this context, to control the thickness...... govern the presence of material in each layer through the thickness of the laminate. Combined with an in-plane density filter, the method enables manufacturers to control the length scale of the geometry while obtaining near discrete designs. Together with the applied manufacturing constraints it is now...... possible for manufacturers to steer the design towards a higher level of manufacturability. The method is demonstrated for mass minimization with displacement and manufacturing constraints. The results show that the method indeed is capable of obtaining near discrete designs which obey the governing...

  16. Cranial vault thickness in primates: Homo erectus does not have uniquely thick vault bones.

    Science.gov (United States)

    Copes, Lynn E; Kimbel, William H

    2016-01-01

    Extremely thick cranial vaults have been noted as a diagnostic characteristic of Homo erectus since the first fossil of the species was identified, but relatively little work has been done on elucidating its etiology or variation across fossils, living humans, or extant non-human primates. Cranial vault thickness (CVT) is not a monolithic trait, and the responsiveness of its layers to environmental stimuli is unknown. We obtained measurements of cranial vault thickness in fossil hominins from the literature and supplemented those data with additional measurements taken on African fossil specimens. Total CVT and the thickness of the cortical and diploë layers individually were compared to measures of CVT in extant species measured from more than 500 CT scans of human and non-human primates. Frontal and parietal CVT in fossil primates was compared to a regression of CVT on cranial capacity calculated for extant species. Even after controlling for cranial capacity, African and Asian H. erectus do not have uniquely high frontal or parietal thickness residuals, either among hominins or extant primates. Extant primates with residual CVT thickness similar to or exceeding H. erectus (depending on the sex and bone analyzed) include Nycticebus coucang, Perodicticus potto, Alouatta caraya, Lophocebus albigena, Galago alleni, Mandrillus sphinx, and Propithecus diadema. However, the especially thick vaults of extant non-human primates that overlap with H. erectus values are composed primarily of cortical bone, while H. erectus and other hominins have diploë-dominated vault bones. Thus, the combination of thick vaults comprised of a thickened diploë layer may be a reliable autapomorphy for members of the genus Homo.

  17. Equivalent Circuit Model for Thick Split Ring Resonators and Thick Spiral Resonators

    CERN Document Server

    Mancera, Laura Maria Pulido

    2014-01-01

    A simple theoretical model which provides circuit parameters and resonance frequency of metallic thick resonators is presented. Two different topologies were studied: the original Pendry's SRR and spiral resonators of two and three turns. Theoretical computations of resonant frequencies are in good agreement with values obtained with a commercial electromagnetic solver. The model could be helpful for designing thick frequency selective surfaces (FSS) based on this types of resonators, so called metasurfaces.

  18. Cranial vault thickness in primates: Homo erectus does not have uniquely thick vault bones.

    Science.gov (United States)

    Copes, Lynn E; Kimbel, William H

    2016-01-01

    Extremely thick cranial vaults have been noted as a diagnostic characteristic of Homo erectus since the first fossil of the species was identified, but relatively little work has been done on elucidating its etiology or variation across fossils, living humans, or extant non-human primates. Cranial vault thickness (CVT) is not a monolithic trait, and the responsiveness of its layers to environmental stimuli is unknown. We obtained measurements of cranial vault thickness in fossil hominins from the literature and supplemented those data with additional measurements taken on African fossil specimens. Total CVT and the thickness of the cortical and diploë layers individually were compared to measures of CVT in extant species measured from more than 500 CT scans of human and non-human primates. Frontal and parietal CVT in fossil primates was compared to a regression of CVT on cranial capacity calculated for extant species. Even after controlling for cranial capacity, African and Asian H. erectus do not have uniquely high frontal or parietal thickness residuals, either among hominins or extant primates. Extant primates with residual CVT thickness similar to or exceeding H. erectus (depending on the sex and bone analyzed) include Nycticebus coucang, Perodicticus potto, Alouatta caraya, Lophocebus albigena, Galago alleni, Mandrillus sphinx, and Propithecus diadema. However, the especially thick vaults of extant non-human primates that overlap with H. erectus values are composed primarily of cortical bone, while H. erectus and other hominins have diploë-dominated vault bones. Thus, the combination of thick vaults comprised of a thickened diploë layer may be a reliable autapomorphy for members of the genus Homo. PMID:26767964

  19. Expectation maximization classification and Laplacian based thickness measurement for cerebral cortex thickness estimation

    Science.gov (United States)

    Holden, Mark; Moreno-Vallecillo, Rafael; Harris, Anthony; Gomes, Lavier J.; Diep, Than-Mei; Bourgeat, Pierrick T.; Ourselin, Sébastien

    2007-03-01

    We describe a new framework for measuring cortical thickness from MR human brain images. This involves the integration of a method of tissue classification with one to estimate thickness in 3D. We have determined an additional boundary detection step to facilitate this. The classification stage utlizes the Expectation Maximisation (EM) algorithm to classify voxels associated with the tissue types that interface with cortical grey matter (GM, WM and CSF). This uses a Gaussian mixture and the EM algorithm to estimate the position and and width of the Gaussians that model the intensity distributions of the GM, WM and CSF tissue classes. The boundary detection stage uses the GM, WM and CSF classifications and finds connected components, fills holes and then applies a geodesic distance transform to determine the GM/WM interface. Finally the thickness of the cortical grey matter is estimated by solving Laplace's equation and determining the streamlines that connect the inner and outer boundaries. The contribution of this work is the adaptation of the classification and thickness measurement steps, neither requiring manual initialisation, and also the validation strategy. The resultant algorithm is fully automatic and avoids the computational expense associated with preserving the cortical surface topology. We have devised a validation strategy that indicates the cortical segmentation of a gold standard brain atlas has a similarity index of 0.91, thickness estimation has subvoxel accuracy evaluated using a synthetic image and precision of the combined segmentation and thickness measurement of 1.54mm using three clinical images.

  20. Creating biological nanomaterials using synthetic biology

    OpenAIRE

    MaryJoe K Rice; Ruder, Warren C.

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic bi...

  1. Thick vortices in SU(2) lattice gauge theory

    OpenAIRE

    Cheluvaraja, Srinath

    2004-01-01

    Three dimensional SU(2) lattice gauge theory is studied after eliminating thin monopoles and the smallest thick monopoles. Kinematically this constraint allows the formation of thick vortex loops which produce Z(2) fluctuations at longer length scales. The thick vortex loops are identified in a three dimensional simulation. A condensate of thick vortices persists even after the thin vortices have all disappeared. The thick vortices decouple at a slightly lower temperature (higher beta) than t...

  2. Research on Blade Thickness Influencing Pump as Turbine

    OpenAIRE

    Sun-Sheng Yang; Chao Wang; Kai Chen; Xin Yuan

    2014-01-01

    Research on the efficiency improvement of pump as turbine (PAT) is inadequate. Blade thickness is an important geometry parameter in blade design. To explore effects of blade thickness on the influence of PAT, numerical research on three different specific speeds of PATs with different blade thickness was carried out. Their performance changes with blade thickness were presented. Besides, the variations of hydraulic loss distribution with increasing blade thickness were performed. Theoretical...

  3. Prediction of Some Biological Film Characteristic

    International Nuclear Information System (INIS)

    A multi components biofilm model has been developed and discussed which accounts for all well established biological processes with biofilm(s): substrate utilization [aerobically, axenically and anaerobically]. Denitrification process. nitrification process. the effect of diffusion and mass transfer limitations. The model has predicted some important characteristics of bio films such as:- space distribution of substrate(s) within bio films. Weight or thickness of biofilm layer (aerobic layer, anoxic layer and anaerobic layer). The results indicates that the relative thickness of biofilm layers (aerobically, anoxically and anaerobic) is highly affected by the availability of the main electron acceptor (O2 and NO3 and the organic load)

  4. The effect of thickness on the magnetic properties of melt-processed YBCO thick films

    International Nuclear Information System (INIS)

    Magnetic properties of melt-processed YBa2Cu3O7-δ thick films have been measured and correlated with features in the microstructure at 4.2 and 77 K for film thicknesses between 50 and 140 μm. A pronounced peak has been observed in both the measured volume magnetization and calculated length scale over which current flows at a film thickness of approximately 53 μm and 4.2 K in fields of up to 10 T. An intra 'hub-spoke' (H-S) type grain current dominates the volume magnetization at this film thickness. Measurements at 77 K, on the other hand, exhibit a peak at 80 μm, the magnitude of which varies significantly with applied field. This correlates well with observed increased connectivity between individual H-S grains and may be accounted for by the flow of inter H-S grain current. The H-S grains transform to a more granular microstructure for films greater than approximately 100 μm thick which is characterized by the presence of smaller diameter current-carrying loops. This is observed as a decrease in the volume magnetization at 4.2 K and a levelling off of this parameter at 77 K with increasing film thickness. Further evidence for the presence of intra H-S and inter H-S grain critical current densities at 4.2 K in films up to a thickness of 80 μm has been observed from length-scale analysis as a function of the difference between maximum and applied magnetic field. A qualitative model for the volume magnetization of the films at 4.2 K in terms of individual contributions from intra H-S grain, inter H-S grain and granular Jc components is proposed. (author)

  5. The relationship between decorrelation time and sample thickness in acute rat brain tissue slices (Conference Presentation)

    Science.gov (United States)

    Brake, Joshua; Jang, Mooseok; Yang, Changhuei

    2016-03-01

    The optical opacity of biological tissue has long been a challenge in biomedical optics due to the strong scattering nature of tissue in the optical regime. While most conventional optical techniques attempt to gate out multiply scattered light and use only unscattered light, new approaches in the field of wavefront shaping exploit the time reversible symmetry of optical scattering in order to focus light inside or through scattering media. While these approaches have been demonstrated effectively on static samples, it has proven difficult to apply them to dynamic biological samples since even small changes in the relative positions of the scatterers within will cause the time symmetry that wavefront shaping relies upon to decorrelate. In this paper we investigate the decorrelation curves of acute rat brain slices for thicknesses in the range 1-3 mm (1/e decorrelation time on the order of seconds) using multi-speckle diffusing wave spectroscopy (MSDWS) and compare the results with theoretical predictions. The results of this study demonstrate that the 1/L^2 relationship between decorrelation time and thickness predicted by diffusing wave spectroscopy provides a good rule of thumb for estimating how the decorrelation of a sample will change with increasing thickness. Understanding this relationship will provide insight to guide the future development of biophotonic wavefront shaping tools by giving an estimate of how fast wavefront shaping systems need to operate to overcome the dynamic nature of biological samples.

  6. Supergravity Induced Interactions on Thick Branes

    CERN Document Server

    Yilmaz, Nejat Tevfik

    2014-01-01

    The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization. The corresponding Einstein's equations are derived and the energy-momentum tensor is calculated. The results are used to derive the dynamical equations of the warped 5D geometry for localized bulk scalar interactions in the framework of thick brane world models. The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.

  7. Skin thickness effects on in vivo LXRF

    International Nuclear Information System (INIS)

    The analysis of lead concentration in bone utilizing LXRF can be adversely effected by overlying issue. A quantitative measure of the attenuation of the 10.5 keV Pb L a x-ray signal by skin and skin equivalent plastic has been conducted. Concentration ranges in plaster of Paris and goat bone from 7 to 90 ppm with attenuators of Lucite reg-sign and pig skin were examined. It is concluded that no quantitative or semi quantitative analysis can be achieved if overlying sue thickness exceeds 3 mm for Ph concentrations of less than 30 porn Ph in bone

  8. Systematic solutions for thick seam mining

    Energy Technology Data Exchange (ETDEWEB)

    Zitz, A.

    1986-06-01

    Room and pillar method and rib pillar extraction in thick seams are analysed for non European coal mining and available equipment, the resulting weaknesses are shown - The analysis forms the basis for the development of the model of an integrated machinery system, consisting of excavating machine, continuous transport system and fully mechanised mobile support. Because the continuous conveyor system still remains to be put to underground tests, comprehensive results from applications of other system components only are available. They are the basis for improvement and source of efficiency improvement of the mentioned mining methods. (orig./MOS). With 21 figs.

  9. OPTIMAL THICKNESS OF A CYLINDRICAL SHELL

    Directory of Open Access Journals (Sweden)

    Paul Ziemann

    2015-01-01

    Full Text Available In this paper an optimization problem for a cylindrical shell is discussed. The aim is to look for an optimal thickness of a shell to minimize the deformation under an applied external force. As a side condition, the volume of the shell has to stay constant during the optimization process. The deflection is calculated using an approach from shell theory. The resulting control-to-state operator is investigated analytically and a corresponding optimal control problem is formulated. Moreover, necessary conditions for an optimal solution are stated and numerical solutions are presented for different examples.

  10. Uncertainties of the ultrasonic thickness gauging (UTTG)

    International Nuclear Information System (INIS)

    The reliability of UTTG was questioned by a senior staff from DOSH in his paper presented during third NDT and Corrosion Management Asia Conference and Exhibition, 4-5 September 2007 at Istana Hotel, Kuala Lumpur. A term 'thickness grow' is an issue need to be solved by NDT community. The technique used by many practitioners gives rise to serious shortcoming in both probability of detection and accuracy of remaining wall assessment. This paper explained and discussed on uncertainty measurement based on the ISO Guide to the Expression of Uncertainty in Measurement (GUM) (1) of real UTTG data obtained from chemical industry. (author)

  11. Cell biology perspectives in phage biology.

    Science.gov (United States)

    Ansaldi, Mireille

    2012-01-01

    Cellular biology has long been restricted to large cellular organisms. However, as the resolution of microscopic methods increased, it became possible to study smaller cells, in particular bacterial cells. Bacteriophage biology is one aspect of bacterial cell biology that has recently gained insight from cell biology. Despite their small size, bacteriophages could be successfully labeled and their cycle studied in the host cells. This review aims to put together, although non-extensively, several cell biology studies that recently pushed the elucidation of key mechanisms in phage biology, such as the lysis-lysogeny decision in temperate phages or genome replication and transcription, one step further.

  12. Measurement of choroidal thickness and macular thickness during and after pregnancy

    Institute of Scientific and Technical Information of China (English)

    D?ndü; Melek; Ulusoy; Necati; Duru; Mustafa; Atas; Hasan; Altιnkaynak; Zeynep; Duru; G?khan; A?maz

    2015-01-01

    AIM: To investigate the effect of pregnancy on subfoveal choroidal thickness(SFCT) and macular thickness in both pregnant and not pregnant healthy women.METHODS: Twenty-nine healthy pregnant women in their third trimester and 36 age-matched healthy women were enrolled in a prospective, cross-sectional study.Foveal and parafoveal thickness in the four quadrants and SFCT were measured by optical coherence tomography(OCT) in the healthy pregnant women(i.e.study group) and healthy women(i.e. control group).OCT measurements were again measured 3mo after delivery in the study group.RESULTS: Mean SFCT measurements in the control group, pregnant women of the study group, and after delivery of the study group were 320.86 ±59.18 μm,387.97 ±59.91 μm, and 332.40 ±26.03 μm, respectively.There was a statistically significant difference in the mean SFCT values between pregnant women of the study group and the control group(P =0.000). Foveal and parafoveal thickness values were not statistically significant in either the study or control group.CONCLUSION: SFCT increases during pregnancy and returns to normal range in the three months after delivery. Macular thickness does not show any change during pregnancy.

  13. Cortical thickness estimation in longitudinal stroke studies: A comparison of 3 measurement methods.

    Science.gov (United States)

    Li, Qi; Pardoe, Heath; Lichter, Renee; Werden, Emilio; Raffelt, Audrey; Cumming, Toby; Brodtmann, Amy

    2015-01-01

    There is considerable controversy about the causes of cognitive decline after stroke, with evidence for both the absence and coexistence of Alzheimer pathology. A reduction in cortical thickness has been shown to be an important biomarker for the progression of many neurodegenerative diseases, including Alzheimer's disease (AD). However, brain volume changes following stroke are not well described. Cortical thickness estimation presents an ideal way to detect regional and global post-stroke brain atrophy. In this study, we imaged a group of patients in the first month after stroke and at 3 months. We compared three methods of estimating cortical thickness on unmasked images: one surface-based (FreeSurfer) and two voxel-based methods (a Laplacian method and a registration method, DiRecT). We used three benchmarks for our analyses: accuracy of segmentation (especially peri-lesional performance), reproducibility, and biological validity. We found important differences between these methods in cortical thickness values and performance in high curvature areas and peri-lesional regions, but similar reproducibility metrics. FreeSurfer had less reliance on manual boundary correction than the other two methods, while reproducibility was highest in the Laplacian method. A discussion of the caveats for each method and recommendations for use in a stroke population is included. We conclude that both surface- and voxel-based methods are valid for estimating cortical thickness in stroke populations.

  14. Fast neutron spectrometry using thick threshold detectors

    Directory of Open Access Journals (Sweden)

    Idiri Z.

    2012-04-01

    Full Text Available This paper discusses the use of thick threshold activation detectors for the characterization of low intensity neutron fields. This technique has been applied to the determination of the spectral emission of a low activity (37 GBq Am-Be source. The reaction rates induced by the neutrons emitted by this source in different thick metallic targets (Al, Si, Fe, In have been measured in the following reactions: 27Al(n,p27Mg, 27Al(n,α24Na, 28Si(n,p28Al, 56Fe(n,p56Mn, 115In(n, n′115mIn and 115In(n, γ116mIn. Each measured reaction rate corresponding to a threshold detector response depends on the spectral emission of the source via a correcting factor. This factor, which takes into account the source detector geometry, the neutron attenuation and diffusion by the detectors, has been determined by Monte Carlo simulation using MCNP5 code. The spectral emission of the neutron source has been generated from the response matrix of the threshold detectors by using different neutron spectrum unfolding methods (Stayn'l, Gravel and Maxed. A fairly good agreement with the assumed ISO spectrum has been achieved.

  15. Formation of thick dielectrophoretic carbon nanotube fibers

    Energy Technology Data Exchange (ETDEWEB)

    Plaado, Margo; Mononen, Robert Matias; Lohmus, Ruenno; Kink, Ilmar; Saal, Kristjan, E-mail: saal@fi.tartu.ee [Institute of Physics, University of Tartu, and Estonian Nanotechnology Competence Centre, 142 Riia Street, 51014 Tartu (Estonia)

    2011-07-29

    The aim of this work was to study the formation process of dielectrophoretic (DEP) carbon nanotube fibers (CNT-fibers) and characterize the fiber properties relevant to their technological applications. The fiber diameter was shown to increase when applied voltage was increased (up to 350 V{sub pp}) and when retraction speed was decreased (down from 400 {mu}m s{sup -1}) in accordance with theoretical expectations. This paper represents the first demonstration of the formation of thick DEP CNT-fibers (up to {approx} 0.4 mm). This is an intriguing result, as it expands the diversity of possible applications of the fibers and facilitates their characterization by analytical methods that require large quantities of the material. The performance of these thick fibers was as follows: a density of {approx} 0.35 g cm{sup -3}, a tensile strength of {approx} 15 MPa, a Young's modulus of {approx} 1 GPa, and an electrical resistivity of {approx} 70 m{Omega} cm.

  16. Thick highly textured (Bi, Pb)-2223 ceramics

    International Nuclear Information System (INIS)

    Dense (Bi, Pb)2Sr2Ca2Cu3O10+x ceramics textured by sinter-forging exhibit superconducting properties among the best for polycrystalline bulk 2223 materials. Investigations showed that the deformation during the sinter-forging process is mainly responsible for the grain alignment of the ceramics. A sharp texture can only be obtained after a strong deformation from the starting cold-pressed powder to the final thin forged disc. To obtain thick ceramics, several thin and highly identically textured discs were linked together by an additional short sinter-forging step. Microscopic observations showed that the interface between the discs disappeared after the hot treatment. Transport critical current measurements performed at 77 K through bars of different sizes confirm that, through an equal texture, the critical current density (JCT = 10,000 A cm-2) is nearly constant with the shape of the bar section: thin or thick, narrow or wide. A ceramic composed of many stacked and sinter-forged discs allowed resistivity and JCT to be measured along the sinter-forging axis. Low anisotropic ratios confirmed the strong link between the thin discs and a very homogeneous whole ceramic. This shape processing of bulk 2223 ceramics is thus attractive for the fabrication of current leads and limiters with high capabilities. (author)

  17. Thick or Thin Ice Shell on Europa?

    Science.gov (United States)

    2007-01-01

    Scientists are all but certain that Europa has an ocean underneath its icy surface, but they do not know how thick this ice might be. This artist concept illustrates two possible cut-away views through Europa's ice shell. In both, heat escapes, possibly volcanically, from Europa's rocky mantle and is carried upward by buoyant oceanic currents. If the heat from below is intense and the ice shell is thin enough (left), the ice shell can directly melt, causing what are called 'chaos' on Europa, regions of what appear to be broken, rotated and tilted ice blocks. On the other hand, if the ice shell is sufficiently thick (right), the less intense interior heat will be transferred to the warmer ice at the bottom of the shell, and additional heat is generated by tidal squeezing of the warmer ice. This warmer ice will slowly rise, flowing as glaciers do on Earth, and the slow but steady motion may also disrupt the extremely cold, brittle ice at the surface. Europa is no larger than Earth's moon, and its internal heating stems from its eccentric orbit about Jupiter, seen in the distance. As tides raised by Jupiter in Europa's ocean rise and fall, they may cause cracking, additional heating and even venting of water vapor into the airless sky above Europa's icy surface. (Artwork by Michael Carroll.)

  18. Coating Thickness of the LHC Superconducting Strands

    CERN Document Server

    Charras, N

    2003-01-01

    In order to determine the time of heat treatment to give to the superconducting Rutherford-type cable, it is essential to know the stabrite (SnAg5%) coating thickness on the superconducting strands. Depending on the heat treatment time applied, the cable will have a contact resistance between strands conform to the LHC specifications. A study on the tin layers thickness was carried out. It concerns the internal and the external strands for all the firms producing these strands for the LHC. The level of control of the tinning process was established for each firm, and correlations between different measuring techniques of the tin layers were achieved, based on the keys process parameters. Finally, a correlation's relationship was found to get an equivalent value of Atomic Adsorption Spectrometry (AAS) from a coulometric result. The AAS measurement gives the total amount of tin in the strand and is the reference nowadays. Thanks to this equivalence, the number of real AAS measurements carried out can be lowered...

  19. Lubricating graphene with nanometer-thick perfluoropolyethers

    Science.gov (United States)

    Li, Lei; Kozbial, Andrew; Iasella, Steven; Taylor, Alexander; Li, Zhiting; Liu, Haitao

    2013-03-01

    Due to its excellent optical, electrical and mechanical properties, graphene has found many important applications. Since graphene is atomic thick, the wear resistance is critical to the reliability of graphene-containing devices. In this study, both monolayer and multilayer graphene were coated with nanometer-thick perfluoropolyethers (PFPEs) and the effect of the nanolubricants on the wear and friction was investigated. The coefficient of friction (COF) was measured with a commercial nanotribometer and the wear was characterized with optically microscopy, AFM and Raman microscopy. Coated with PFPEs, monolayer graphene on silicon showed significantly decreased COF. However, the wear resistance was only slightly improved. For multilayer graphene on nickel substrate coated with PFPEs, COF also decreased significantly. Meanwhile, the wear resistance was improved substantially. The results were discussed based on the graphene-substrate adhesion and the thickenss of the graphene. The learning here potentially will lead to the methodology to improve the reliability of graphene-containing devices. We thank TTRF for financial support.

  20. Thin, thick and dark discs in LCDM

    CERN Document Server

    Read, J I; Agertz, O; Debattista, Victor P

    2008-01-01

    In a LCDM cosmology, the Milky Way accretes satellites into the stellar disc. We use cosmological simulations to assess the frequency of near disc plane and higher inclination accretion events, and collisionless simulations of satellite mergers to quantify the final state of the accreted material and the effect on the thin disc. On average, a Milky Way-sized galaxy has 1.5 subhalos with vmax>80km/s; 5 with vmax>60km/s; and 13 with vmax>40km/s merge at redshift z>1. A third of these merge at an impact angle 20 degrees) are twice as likely as low inclination ones. These lead to structures that closely resemble the recently discovered inner/outer stellar halos. They also do more damage to the Milky Way stellar disc creating a more pronounced flare, and warp; both long-lived and consistent with current observations. The most massive mergers (vmax > 80km/s) heat t he thin disc enough to produce a thick disc. These heated thin disc stars are essential for obtaining a thick disc as massive as that seen in the Milky ...

  1. Cutting work in thick section cryomicrotomy.

    Science.gov (United States)

    Saubermann, A J; Riley, W D; Beeuwkes, R

    1977-09-01

    The forces during cryosectioning were measured using miniature strain gauges attached to a load cell fitted to the drive arm of the Porter-Blum MT-2 cryomicrotome. Work was calculated and the data normalized to a standard (1 mm X 1 mm X 0.5 micrometer) section. Thermal energy generated was also calculated. Five parameters were studied: cutting angle, thickness, temperature, hardness, and block shape. Force patterns could be divided into three major groups thought to represent cutting (Type I), large fracture planes greater than 10 micrometer in length (Type II), and small fracture planes less than 10 micrometer in length (Type III). Type I and Type II produced satisfactory sections. Work in cutting ranged from an average of 78.4 muJ to 568.8 muJ. Cutting angle and temperature had the greatest effect on sectioning. Heat generated would be sufficient to cause through-section melting for 0.5 micrometer thick sections assuming the worst possible case, namely that all heat went into the section without loss. Presence of a Type II pattern (large fracture pattern) is thought to be presumptive evidence against thawing. PMID:606833

  2. Effect of film thickness on the antifouling performance of poly(hydroxy-functional methacrylates) grafted surfaces.

    Science.gov (United States)

    Zhao, Chao; Li, Lingyan; Wang, Qiuming; Yu, Qiuming; Zheng, Jie

    2011-04-19

    The development of nonfouling biomaterials to prevent nonspecific protein adsorption and cell/bacterial adhesion is critical for many biomedical applications, such as antithrombogenic implants and biosensors. In this work, we polymerize two types of hydroxy-functional methacrylates monomers of 2-hydroxyethyl methacrylate (HEMA) and hydroxypropyl methacrylate (HPMA) into polymer brushes on the gold substrate via surface-initiated atom transfer radical polymerization (SI-ATRP). We systematically examine the effect of the film thickness of polyHEMA and polyHPMA brushes on their antifouling performance in a wide range of biological media including single-protein solution, both diluted and undiluted human blood serum and plasma, and bacteria culture. Surface plasmon resonance (SPR) results show a strong correlation between antifouling property and film thickness. Too thin or too thick polymer brushes lead to large protein adsorption. Surfaces with the appropriate film thickness of ∼25-45 nm for polyHPMA and ∼20-45 nm for polyHEMA can achieve almost zero protein adsorption (thickness of ∼20-30 nm adsorb only ∼3.0 and ∼3.5 ng/cm(2) proteins, respectively, while polyHPMA brushes at a film thickness of ∼30 nm adsorb more proteins of ∼13.5 and ∼50.0 ng/cm(2), respectively. Moreover, both polyHEMA and polyHPMA brushes with optimal film thickness exhibit very low bacteria adhesion. The excellent antifouling ability and long-term stability of polyHEMA and polyHPMA brushes make them, especially for polyHEMA, effective and stable antifouling materials for usage in blood-contacting devices. PMID:21405141

  3. Thickness Dependence of Resistivity and Optical Reflectance of ITO Films

    Institute of Scientific and Technical Information of China (English)

    GAO Mei-Zhen; JOB R; XUE De-Sheng; FAHRNER W R

    2008-01-01

    @@ Indium-tin-oxide (ITO) films deposited on crystalline silicon wafer and Coming glass are prepared by directcurrent magnetron sputtering method at room temperature with various thicknesses. The thickness dependences of structure, resistance and optical reflectance of ITO films are characterized. The results show that when the film thickness is less than 4Ohm, the resistivity and optical reflectance of the ITO tilm changes remarkably with thickness. The optoelectrical properties trend to stabilize when the thickness is over 55 nm. The GXRD result implies that the ITO film begins to crystallize if only the thickness is large enough.

  4. Biological effects of radiation

    International Nuclear Information System (INIS)

    This fourth chapter presents: cell structure and metabolism; radiation interaction with biological tissues; steps of the production of biological effect of radiation; radiosensitivity of tissues; classification of biological effects; reversibility, transmissivity and influence factors; pre-natal biological effects; biological effects in therapy and syndrome of acute irradiation

  5. Influence of biofilm thickness on micropollutants removal in nitrifying MBBRs

    DEFF Research Database (Denmark)

    Torresi, Elena; Andersen, Henrik Rasmus; Smets, Barth F.;

    The removal of pharmaceuticals was investigated in nitrifying Moving Bed Biofilm Reactors (MBBRs) containing carriers with different biofilm thicknesses. The biofilm with the thinnest thickness was found to have the highest nitrification and biotransformation rate for some key pharmaceuticals...

  6. Saturated thickness of the Madison aquifer, Black Hills, South Dakota.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set is a polygon coverage created in ARC/INFO that represents the saturated thickness of the Madison aquifer, which includes the entire thickness of the...

  7. GALAH Survey: Chemically Tagging the Thick Disk

    CERN Document Server

    Bland-Hawthorn, J; Freeman, K

    2015-01-01

    The GALAH survey targets one million stars in the southern hemisphere down to a limiting magnitude of V = 14 at the Anglo- Australian Telescope. The project aims to measure up to 30 elemental abundances and radial velocities (~1 km/s accuracy) for each star at a resolution of R = 28000. These elements fall into 8 independent groups (e.g. alpha, Fe peak, r-process). For all stars, Gaia will provide distances to 1% and transverse velocities to 1 km/s or better, giving us a 14D set of parameters for each star, i.e. 6D phase space and 8D abundance space. There are many scientic applications but here we focus on the prospect of chemically tagging the thick disk and making a direct measurement of how stellar migration evolves with cosmic time.

  8. Cortical Thickness Changes Associated with Photoparoxysmal Response

    DEFF Research Database (Denmark)

    Hanganu, Alexandru; Groppa, Stanislav A; Deuschl, Günther;

    2014-01-01

    Photoparoxysmal response (PPR) is an EEG trait of spike and spike-wave discharges in response to photic stimulation that is closely linked to idiopathic generalized epilepsy (IGE). In our previous studies we showed that PPR is associated with functional alterations in the occipital and frontal...... compared these groups with a group of PPR-negative-healthy-controls (HC, n = 17; 15.3 ± 3.6 years; 6 males). Our results revealed an increase of cortical thickness in the occipital, frontal and parietal cortices bilaterally in PPR-positive-subjects in comparison to HC. Moreover PPR...... the occipital lobe, frontoparietal regions and temporal lobe, which also show functional changes associated with PPR. Patients with epilepsy present changes in the temporal lobe and supplementary motor area....

  9. The economics of repeated tube thickness surveys

    International Nuclear Information System (INIS)

    The use of tube thickness surveys in boilers is an example of a commonly applied condition monitoring (CM) technique for maintenance and it leads to condition-based maintenance (CBM) of the boiler tubes. There are, however, limits to the economics of this type of strategy which are frequently overlooked in discussion of CBM strategies. This paper considers several models of maintenance strategies. Conditions in which breakdown maintenance (BM), routine total replacement (routine maintenance, RM) and condition-based replacement (which for simplicity is referred to as CM) are considered. Some general rules about the economical range of each strategy are developed. The case study examines the use of ultrasonic testing of boiler tubes in power stations in some detail

  10. Full-thickness endometriosis of the bladder

    DEFF Research Database (Denmark)

    Kjer, Jens Jørgen; Kristensen, Jens; Hartwell, Dorthe;

    2014-01-01

    OBJECTIVE: To draw attention to the rare condition of endometriosis in the bladder. This is correlated with symptoms not normally connected to endometriosis and therefore often remains underdiagnosed for years. DESIGN AND SETTING: Retrospective study in a university teaching hospital, one of two...... referral centres in Denmark for surgical treatment of stage III and IV endometriosis. POPULATION: Thirty-one women with deep infiltrating bladder endometriosis. METHODS: All women presenting in the Department of Obstetrics and Gynaecology with deep infiltrating bladder endometriosis between March 2002...... and March 2011. We included only patients with symptomatic full-thickness bladder detrusor endometriosis and mucosal involvement. All patients had had bladder symptoms for two to seven years. MAIN OUTCOME MEASURES: Symptoms after surgery and recurrence rate. RESULTS: The main preoperative symptom...

  11. Fracture resistance of monolithic zirconia molar crowns with reduced thickness

    OpenAIRE

    Nakamura, Keisuke; Harada, A.; Inagaki, R.; Kanno, Taro; Niwano, Y; Milleding, Percy; Ørtengren, Ulf Thore

    2015-01-01

    Objectives. The purpose of the present study was to analyze the relationship between fracture load of monolithic zirconia crowns and axial/occlusal thickness, and to evaluate the fracture resistance of monolithic zirconia crowns with reduced thickness in comparison with that of monolithic lithium disilicate crowns with regular thickness. Materials and methods. Monolithic zirconia crowns (Lava Plus Zirconia, 3M/ESPE) with specified axial/occlusal thicknesses and lithium disilica...

  12. Kinetics of the crust thickness development of bread during baking

    OpenAIRE

    Soleimani Pour-Damanab, Alireza; Jafary, A.; Rafiee, Sh.

    2012-01-01

    The development of crust thickness of bread during baking is an important aspect of bread quality and shelf-life. Computer vision system was used for measuring the crust thickness via colorimetric properties of bread surface during baking process. Crust thickness had a negative and positive relationship with Lightness (L*) and total color change (E*) of bread surface, respectively. A linear negative trend was found between crust thickness and moisture ratio of bread samples. A simple mathemat...

  13. Human enamel thickness and ENAM polymorphism

    Science.gov (United States)

    Daubert, Diane M; Kelley, Joanna L; Udod, Yuriy G; Habor, Carolina; Kleist, Chris G; Furman, Ilona K; Tikonov, Igor N; Swanson, Willie J; Roberts, Frank A

    2016-01-01

    The tooth enamel development gene, enamelin (ENAM), showed evidence of positive selection during a genome-wide scan of human and primate DNA for signs of adaptive evolution. The current study examined the hypothesis that a single-nucleotide polymorphism (SNP) C14625T (rs7671281) in the ENAM gene identified in the genome-wide scan is associated with a change in enamel phenotype. African Americans were selected as the target population, as they have been reported to have a target SNP frequency of approximately 50%, whereas non-Africans are predicted to have a 96% SNP frequency. Digital radiographs and DNA samples from 244 teeth in 133 subjects were analysed, and enamel thickness was assessed in relation to SNP status, controlling for age, sex, tooth number and crown length. Crown length was found to increase with molar number, and females were found to have thicker enamel. Teeth with larger crowns also had thicker enamel, and older subjects had thinner enamel. Linear regression and generalized estimating equations were used to investigate the relationship between enamel thickness of the mandibular molars and ENAM SNP status; enamel in subjects with the derived allele was significantly thinner (P=0.040) when the results were controlled for sex, age, tooth number and crown length. The derived allele demonstrated a recessive effect on the phenotype. The data indicate that thinner dental enamel is associated with the derived ENAM genotype. This is the first direct evidence of a dental gene implicated in human adaptive evolution as having a phenotypic effect on an oral structure. PMID:27357321

  14. Human enamel thickness and ENAM polymorphism.

    Science.gov (United States)

    Daubert, Diane M; Kelley, Joanna L; Udod, Yuriy G; Habor, Carolina; Kleist, Chris G; Furman, Ilona K; Tikonov, Igor N; Swanson, Willie J; Roberts, Frank A

    2016-01-01

    The tooth enamel development gene, enamelin (ENAM), showed evidence of positive selection during a genome-wide scan of human and primate DNA for signs of adaptive evolution. The current study examined the hypothesis that a single-nucleotide polymorphism (SNP) C14625T (rs7671281) in the ENAM gene identified in the genome-wide scan is associated with a change in enamel phenotype. African Americans were selected as the target population, as they have been reported to have a target SNP frequency of approximately 50%, whereas non-Africans are predicted to have a 96% SNP frequency. Digital radiographs and DNA samples from 244 teeth in 133 subjects were analysed, and enamel thickness was assessed in relation to SNP status, controlling for age, sex, tooth number and crown length. Crown length was found to increase with molar number, and females were found to have thicker enamel. Teeth with larger crowns also had thicker enamel, and older subjects had thinner enamel. Linear regression and generalized estimating equations were used to investigate the relationship between enamel thickness of the mandibular molars and ENAM SNP status; enamel in subjects with the derived allele was significantly thinner (P=0.040) when the results were controlled for sex, age, tooth number and crown length. The derived allele demonstrated a recessive effect on the phenotype. The data indicate that thinner dental enamel is associated with the derived ENAM genotype. This is the first direct evidence of a dental gene implicated in human adaptive evolution as having a phenotypic effect on an oral structure. PMID:27357321

  15. Through-thickness stress relaxation in bacterial cellulose hydrogel.

    Science.gov (United States)

    Gao, Xing; Kuśmierczyk, Piotr; Shi, Zhijun; Liu, Changqing; Yang, Guang; Sevostianov, Igor; Silberschmidt, Vadim V

    2016-06-01

    Biological hydrogels, e.g. bacterial cellulose (BC) hydrogel, attracted increasing interest in recent decades since they show a good potential for biomedical engineering as replacements of real tissues thanks mainly to their good biocompatibility and fibrous structure. To select potential candidates for such applications, a comprehensive understanding of their performance under application-relevant conditions is needed. Most hydrogels demonstrate time-dependent behaviour due to the contribution of their liquid phase and reorientation of fibres in a process of their deformation. To quantify such time-dependent behaviour is crucial due to their exposure to complicated loading conditions in body environment. Some hydrogel-based biomaterials with a multi-layered fibrous structure demonstrate a promise as artificial skin and blood vessels. To characterise and model time-dependent behaviour of these multi-layered hydrogels along their through-thickness direction is thereby of vital importance. Hence, a holistic study combining mechanical testing and micro-morphological observations of BC hydrogel with analytical modelling of its relaxation behaviour based on fraction-exponential operators was performed. The results show a good potential to use a fraction-exponential model to describe such behaviour of multi-layered hydrogels, especially at stages of stress decay at low forces and of stress equilibrium at high forces. PMID:26749210

  16. Sexual orientation related differences in cortical thickness in male individuals.

    Directory of Open Access Journals (Sweden)

    Christoph Abé

    Full Text Available Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI in order to compare regional cortical thickness (Cth and subcortical volumes of homosexual men (hoM, heterosexual men (heM and heterosexual women (heW. hoM (and heW had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation.

  17. Thick-film analysis: literature search and bibliography

    International Nuclear Information System (INIS)

    A literature search was conducted to support development of in-house diagnostic testing of thick film materials for hybrid microcircuits. A background literature review covered thick film formulation, processing, structure, and performance. Important material properties and tests were identified and several test procedures were obtained. Several tests were selected for thick film diagnosis at Bendix Kansas City. 126 references

  18. Thick Translation as a New Trend of Translation Studies

    Institute of Scientific and Technical Information of China (English)

    饶莉

    2016-01-01

    This paper, based on the development and history of thick translation, is intended to carry out a comparative critic of the interpretations of“thick translation”proposed by different scholars so as to explore the profound meanings and significance of“thick translation”as a new strategy, which has reflected and predicted the new trend of translation studies.

  19. Measurement Method of the Thickness Uniformity for Polymer Films

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Several methods for investigating the thickness uniformity of polymer thin films are presented as well as their measurement principles. A comparison of these experimental methods is given.The cylindrical lightwave reflection method is found to can obtain the thickness distribution along a certain direction.It is a simple and suitable method to evaluate the film thickness uniformity.

  20. ASYMPTOTIC ANALYSIS OF LINEARLY ELASTIC SHALLOW SHELLS WITH VARIABLE THICKNESS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The author considers a linearly elastic shallow shell with variable thickness and shows that, as the thickness of the shell goes to zero, the solution of the three-dimensional equations converges to the solution of the two-dimensional shallow shell equations with variable thickness.

  1. Thickness Evaluation of Aluminium Plate Using Pulsed Eddy Current Technique

    Science.gov (United States)

    Singh, Gurpartap; Bapat, Harsh Madhukar; Singh, Bhanu Pratap; Bandyopadhyay, Manojit; Puri, Rakesh Kumar; Badodkar, Deepak Narayanrao

    2013-10-01

    This paper describes a pulsed eddy current (PEC) based non-destructive testing system used for detection of thickness variation in aluminium plate. A giant magneto-resistive sensor has been used instead of pick up coil for detecting resultant magnetic field. The PEC response signals obtained from 1 to 5 mm thickness change in aluminium plate were investigated. Two time domain features, namely peak value and time to peak, of PEC response were used for extracting information about thickness variation in aluminium plate. The variation of peak value and time to peak with thickness was compared. A program was developed to display the thickness variation of the tested sample.

  2. The importance of ultrasonographic measurement of peritoneal wall thickness in pediatric chronic peritoneal dialysis patients.

    Science.gov (United States)

    Yavaşcan, Önder; Aksu, Nejat; Alparslan, Caner; Sarıtaş, Serdar; Elmas, Cengiz Han; Eraslan, Ali Nihat; Duman, Soner; Mir, Sevgi

    2015-04-01

    Loss of peritoneal function due to peritoneal fibrosing syndrome (PFS) is a major factor leading to treatment failure in chronic peritoneal dialysis (PD) patients. Although the precise biologic mechanisms responsible for these changes have not been defined, the general assumption is that alterations in peritoneal function are related to structural changes in the peritoneal membrane. Studies of the peritoneal membrane by non-invasive ultrasonography (US) in chronic PD patients are limited. The aim of the present study is to assess the relationship between functional parameters of peritoneum and peritoneal thickness measured by US in children treated by chronic PD. We recruited two groups of patients: 23 subjects (13 females, 10 males) on chronic PD (patient group) and 26 (7 females, 19 males) on predialysis out-patient follow-up (creatinine clearance: 20-60 mL/min/1.73 m(2)) (control group). Age, sex, weight, height, body mass index (BMI), chronic PD duration, episodes of peritonitis and the results of peritoneal equilibration test (PET) were recorded. Hemoglobin (Hb), blood pressure (BP), left ventricular mass index (LVMI) and renal osteodystrophy (ROD) parameters were also obtained. The thickness of the parietal peritoneum was measured by trans-abdominal US in all children. Statistical analyses were performed by using Student's t and Pearson's correlation tests. Mean peritoneal thickness in chronic PD patients (1028.26 ± 157.26 μm) was significantly higher than control patients (786.52 ± 132.33). Mean peritoneal thickness was significantly correlated with mean body height (R(2) = 0.93, p thickness and Hb, BP, LVMI and ROD parameters. In conclusion, ultrasonographic measurement of peritoneal membrane thickness is a simple and non-invasive method in chronic PD children. This diagnostic tool likely enables to assess peritoneal structure and function in these patients.

  3. Oriented Growth of PZT thick film embedded with PZT nanoparticles

    Institute of Scientific and Technical Information of China (English)

    DUAN Zhong-xia; YUAN Jie; ZHAO Quan-liang; LU Ran; CAO Mao-sheng

    2009-01-01

    This paper reports that dense and crack-free (100) oriented lead zirconate titanate (Pb(Zr0.52Ti0.48)O3,PZT) thick film embedded with PZT nanoparticles has been successfully fabricated on Pt/Cr/SiO2/Si substrate by using PT transition layer and PVP additive. The thick film possesses single-phase perovskite structure and perfectly (100) oriented. The (100) orientation degree of the PZT films strongly depended on annealing time and for the 4 μm-thick PZT film which was annealed at 700 ℃ for 5 min is the largest. The (100) orientation degree of the PZT thick film gradually strengthen along with the thickness of film decreasing. The 3 μm-thick PZT thick film which was annealed at 700 ℃ for 5 min has the strongest (100) orientation degree, which is 82. 3%.

  4. Film-thickness Error Analysis of Optical Disk Systems

    Institute of Scientific and Technical Information of China (English)

    WANG Yang; GU Donghong; GAN Fuxi

    2001-01-01

    It is difficult to exactly control the film thickness of optical disk multilayer in the actual coating process. The thickness error becomes a main factor affecting the optical characters of the film system. The thickness error′s sensitivity factor of dielectric optical multilayer is derived from the optical matrix in this paper. The effect of the thickness error on the reflectivity or reflectivity contrast of the optical disk multilayer is analyzed with a numerical calculation. The sensitivities to thickness error for different layers or in different film-thickness ranges are compared and discussed. A sketchy method defining allowable thickness error is given. Some experimental results verify the applicability of our theoretical analysis.

  5. Synthetic biology: insights into biological computation.

    Science.gov (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc

    2016-04-18

    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  6. Synthetic biology: insights into biological computation.

    Science.gov (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc

    2016-04-18

    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  7. Translational environmental biology: cell biology informing conservation.

    Science.gov (United States)

    Traylor-Knowles, Nikki; Palumbi, Stephen R

    2014-05-01

    Typically, findings from cell biology have been beneficial for preventing human disease. However, translational applications from cell biology can also be applied to conservation efforts, such as protecting coral reefs. Recent efforts to understand the cell biological mechanisms maintaining coral health such as innate immunity and acclimatization have prompted new developments in conservation. Similar to biomedicine, we urge that future efforts should focus on better frameworks for biomarker development to protect coral reefs.

  8. Cladding Attachment Over Thick Exterior Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P. [Building Science Corporation, Somerville, MA (United States); Eng, P. [Building Science Corporation, Somerville, MA (United States); Lepage, R. [Building Science Corporation, Somerville, MA (United States)

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1.What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2.Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3.What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  9. Cladding Attachment Over Thick Exterior Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P.; Eng, P.; Lepage, R.

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  10. Optically thick outflows in ultraluminous supersoft sources

    CERN Document Server

    Urquhart, Ryan

    2015-01-01

    Ultraluminous supersoft sources (ULSs) are defined by a thermal spectrum with colour temperatures ~0.1 keV, bolometric luminosities ~ a few 10^39 erg/s, and almost no emission above 1 keV. It has never been clear how they fit into the general scheme of accreting compact objects. To address this problem, we studied a sample of seven ULSs with extensive Chandra and XMM-Newton coverage. We find an anticorrelation between fitted temperatures and radii of the thermal emitter, and no correlation between bolometric luminosity and radius or temperature. We compare the physical parameters of ULSs with those of classical supersoft sources, thought to be surface-nuclear-burning white dwarfs, and of ultraluminous X-ray sources (ULXs), thought to be super-Eddington stellar-mass black holes. We argue that ULSs are the sub-class of ULXs seen through the densest wind, perhaps an extension of the soft-ultraluminous regime. We suggest that in ULSs, the massive disk outflow becomes effectively optically thick and forms a large ...

  11. Milky Way's Thick and Thin disk: Is there distinct thick disk?

    CERN Document Server

    Kawata, D

    2016-01-01

    This article is based on our discussion session on Milky Way models at the 592 WE-Heraeus Seminar, Reconstructing the Milky Way's History: Spectroscopic Surveys, Asteroseismology and Chemodynamical models. The discussion focused on the following question: "Are there distinct thick and thin disks?". The answer to this question depends on the definition one adopts for thin and thick disks. The participants of this discussion converged to the idea that there are at least two different types of disks in the Milky Way. However, there are still important open questions on how to best define these two types of disks (chemically, kinematically, geometrically or by age?). The question of what is the origin of the distinct disks remains open. The future Galactic surveys which are highlighted in this conference should help us answering these questions. The almost one-hour debate involving researchers in the field representing different modelling approaches (Galactic models such as TRILEGAL, Besancon and Galaxia, chemica...

  12. Hydrophobic matching between melittin and phosphocholine lipid bilayers having different thicknesses

    Science.gov (United States)

    Heller, William; Qian, Shuo

    2014-03-01

    The lipid bilayer of the cellular membrane is more than a simple medium that houses proteins with specific function. Instead, it is an elastic medium that plays an active role in the function of the membrane and that both drives the function of membrane proteins and alters its properties in response to their presence. The conceptual simplicity of membrane active peptides makes them attractive model systems for studying membrane-protein interactions. Melittin, a 27 amino acid cationic peptide having a helix-hinge-helix motif, is one of the most extensively studied examples. Small-angle neutron scattering (SANS) measurements of melittin associated with lipid bilayer vesicles having different hydrocarbon thicknesses showed that the bilayer thickness stretches to match the thickness of the peptide in a manner consistent with a rigid, extended melittin having its helical axis oriented parallel to the bilayer normal. This behavior is surprising considering the helix-hinge-helix motif of the peptide and in contrast to studies indicating that transmembrane helices tilt with respect to the bilayer normal to accommodate differences in hydrophobic thicknesses. Possible sources of the discrepancy will be discussed and explored. This research at SNS and HFIR of ORNL was supported by the US Department of Energy Office of Basic Energy Sciences and the Office of Biological and Environmental Research (ERKP291).

  13. Pictures of Synthetic Biology

    OpenAIRE

    Cserer, Amelie; Seiringer, Alexandra

    2009-01-01

    This article is concerned with the representation of Synthetic Biology in the media and by biotechnology experts. An analysis was made of German-language media articles published between 2004 and 2008, and interviews with biotechnology-experts at the Synthetic Biology conference SB 3.0 in Zurich 2007. The results have been reflected in terms of the definition of Synthetic Biology, applications of Synthetic Biology and the perspectives of opportunities and risks. In the media, Synthetic Biolog...

  14. Computational Systems Chemical Biology

    OpenAIRE

    Oprea, Tudor I.; May, Elebeoba E.; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically-based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology, SCB (Oprea et al., 2007).

  15. Through thick and thin: Structure of the Galactic thick disc from extragalactic surveys

    CERN Document Server

    Kordopatis, G; Irwin, M; Gilmore, G; Wyse, R F G; Tolstoy, E; de Laverny, P; Recio-Blanco, A; Battaglia, G; Starkenburg, E

    2013-01-01

    We aim to understand the accretion history of the Milky Way by exploring the vertical and radial properties of the Galactic thick disc. We study the chemical and kinematic properties of roughly a thousand spectra of faint magnitude foreground Galactic stars observed serendipitously during extra-galactic surveys in four lines-of-sight: three in the southern Galactic hemisphere (surveys of the Carina, Fornax and Sculptor dwarf spheroidal galaxies) and one in the northern Galactic hemisphere (a survey of the Sextans dwarf spheroidal galaxy). The foreground stars span distances up to 3kpc from the Galactic plane and Galactocentric radii up to 11kpc. Only three lines-of-sight have a sufficient number of foreground stars for a robust analysis. Towards Sextans in the Northern Galactic hemisphere and Sculptor in the South, we measure a consistent decrease in mean metallicity with height from the Galactic plane, suggesting a chemically symmetric thick disc. This decrease can either be due to an intrinsic thick disc me...

  16. Beam-time for biology

    CERN Multimedia

    Jordan Juras

    2010-01-01

    There's no question that playing with mercury or handling radioactive cadmium with your bare hands is a risky business. But understanding how these and other toxic metals interact with biomolecules within the body is a challenging feat; one for which the ISOLDE IS488 collaboration hopes to provide valuable insight.   General view of the ISOLDE experimental area. Unlike most of the facilities at CERN's accelerator complex, ISOLDE is not targeted mainly at particle physics. Rather, it produces radioactive nuclei during proton bombardment to study, among other things, physical and biological chemistry. At ISOLDE, the 1.4 GeV proton beam of the PS Booster (an early stage in CERN's accelerator complex) produces nuclear reactions in a thick target, creating a large variety of radioactive nuclei, which are mass-separated for use in experiments. In the case of the IS488 collaboration, the ion beam is directed into ice. "We implant radioactive metal ions into ice", explains Monika Stac...

  17. Thickness Measurements from Single X-ray Phase-contrast Speckle Projection

    CERN Document Server

    Xi, Yan; Ma, Jingchen; Zhao, Jun

    2015-01-01

    We propose a one-shot thickness measurement method for sponge-like structures using a propagation-based X-ray phase-contrast imaging (P-PCI) method. In P-PCI, the air-material interface refracts the incident X-ray. Refracted many times along their paths by such a structure, incident X-rays propagate randomly within a small divergent angle range, resulting in a speckle pattern in the captured image. We found structure thickness and contrast of a phase-contrast projection are directly related in images. This relationship can be described by a natural logarithm equation. Thus, from the one phase-contrast view, depth information can be retrieved from its contrast. Our preliminary biological experiments indicate promise in its application to measurements requiring in vivo and ongoing assessment of lung tumor progression.

  18. Central Corneal Thickness in Adult Chinese

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The central corneal thickness (CCT) in age 48 years or less of Chinese was characterized and its relationship with gender, age, refraction and intraocular pressure (IOP) was investigated.Right eyes of 1669 participants were included in this study (880 men, 52.7 % and 789 women,47.3 %). Mean age of the samples was 23.8±5.9 years. After the examination of corneal topography and refraction, Goldman applanation tonometry was carried out by one physician. Tonometric values were the mean of three consecutive readings. Subsequently, another physician carried out ultrasonic pachymetry with the DGH 2000 AP ultrasonic pachymeter. Six measuremen ts were made at the center of the cornea of each eye. The mean value was used for analysis. The results showed that mean CCT of male participants was 551.33± 34. 62 μm, 5.79 μm more than that of female participants. Linear regression analyses revealed that CCT was negatively related with age only in female and no association was found between refractive status and CCT. IOP was positively related to CCT, and there was a difference in IOP of 1.5 mmHg (1 mmHg=0. 133 kPa) per 100 μm difference in CCT. Ocular hypertension group was prone to have thicker cornea than average. The results indicated that in adult Chinese CCT tended to decrease with aging in female only. IOP measured by Goldmann tonometry was positively related with CCT so that CCT should be measured along with IOP.

  19. Mapping gray matter volume and cortical thickness in Alzheimer's disease

    Science.gov (United States)

    Guo, Xiaojuan; Li, Ziyi; Chen, Kewei; Yao, Li; Wang, Zhiqun; Li, Kuncheng

    2010-03-01

    Gray matter volume and cortical thickness are two important indices widely used to detect neuropathological changes in brain structural magnetic resonance imaging. Using optimized voxel-based morphometry (VBM) protocol and surface-based cortical thickness measure, this study comprehensively investigated the regional changes in cortical gray matter volume and cortical thickness in Alzheimer's disease (AD). Thirteen patients with AD and fourteen age- and gender-matched healthy controls were included in this study. Results showed that voxel-based gray matter volume and cortical thickness reductions were highly correlated in the temporal lobe and its medial structure in AD. Moreover significant reduced cortical regions of gray matter volume were obviously more than that of cortical thickness. These findings suggest that gray matter volume and cortical thickness, as two important imaging markers, are effective indices for detecting the neuroanatomical alterations and help us understand the neuropathology from different views in AD.

  20. Multiple High Voltage Pulse Stressing of Polymer Thick Film Resistors

    Directory of Open Access Journals (Sweden)

    Busi Rambabu

    2014-01-01

    Full Text Available The purpose of this paper is to study high voltage interactions in polymer thick film resistors, namely, polyvinyl chloride- (PVC- graphite thick film resistors, and their applications in universal trimming of these resistors. High voltages in the form of impulses for various pulse durations and with different amplitudes have been applied to polymer thick film resistors and we observed the variation of resistance of these resistors with high voltages. It has been found that the resistance of polymer thick film resistors decreases in the case of higher resistivity materials and the resistance of polymer thick film resistor increases in the case of lower resistivity materials when high voltage impulses are applied to them. It has been also found that multiple high voltage pulse (MHVP stressing can be used to trim the polymer thick film resistors either upwards or downwards.

  1. Integrated thick-film nanostructures based on spinel ceramics

    OpenAIRE

    Klym, Halyna; Hadzaman, Ivan; Shpotyuk, Oleh; Brunner, Michael

    2014-01-01

    Integrated temperature-humidity-sensitive thick-film structures based on spinel-type semiconducting ceramics of different chemical compositions and magnesium aluminate ceramics were prepared and studied. It is shown that temperature-sensitive thick-film structures possess good electrophysical characteristics in the region from 298 to 358 K. The change of electrical resistance in integrated thick-film structures is 1 order, but these elements are stable in time and can be successfully used for...

  2. Device for rapid statistic processing of radioisotope thickness gage data

    International Nuclear Information System (INIS)

    The device operation for statistic data processing being a part of the system for rapid control of the tubes wall thickness at the hot finishing outlet of pilger aggreate is described. The device permits to obtain at the light board the wall thickness distribution and in digital form data on average value of the thickness and its spread at each tube. The presence of the described equipment guarantees high accuracy of rolled tubes

  3. Integrated thick-film nanostructures based on spinel ceramics.

    Science.gov (United States)

    Klym, Halyna; Hadzaman, Ivan; Shpotyuk, Oleh; Brunner, Michael

    2014-03-26

    Integrated temperature-humidity-sensitive thick-film structures based on spinel-type semiconducting ceramics of different chemical compositions and magnesium aluminate ceramics were prepared and studied. It is shown that temperature-sensitive thick-film structures possess good electrophysical characteristics in the region from 298 to 358 K. The change of electrical resistance in integrated thick-film structures is 1 order, but these elements are stable in time and can be successfully used for sensor applications.

  4. Estimation of Damping in Layered Welded Structures with Unequal Thickness

    OpenAIRE

    Bhagat Singh; Bijoy Kumar Nanda

    2012-01-01

    The present work is focused on the study of damping mechanism in layered and welded cantilever beams with unequal thickness. It is observed that a number of vital parameters such as: thickness ratio, pressure distribution characteristics, relative slip and kinematic co-efficient of friction at the interfaces, initial amplitude of excitation, length and thickness of the beam specimen govern the damping capacity of these structures. Experiments have been conducted in order to study the effect o...

  5. Studying microbial populations in relation to thick juice storage

    OpenAIRE

    Justé, Annelies; Krause, M.S.; Lievens, Bart; Klingeberg, M; Michiels, Christiaan; Marsh, T.L.; Willems, Kris

    2006-01-01

    Background and Aims: Storing sugar extracts as thick juice, a form of sucrose syrup, is common practice in the sugar industry. Even under good storage practices, microbiological problems can sometimes occur. Improving control of these microflora-related problems requires greater understanding of microbial dynamics of thick juice storage. Therefore, the objective of this study was to identify the microflora associated with thick juice degradation in order to define better process controls....

  6. Dependence of film tension on the thickness of smectic films.

    Science.gov (United States)

    Jaquet, R; Schneider, F

    2003-02-01

    The film tension tau of free standing S(A) films has been measured for films with thicknesses between 2 and 150 layers. There is a clear increase of tau with the thickness for very thin films and a nonlinear slower increase for high thickness. The nonlinearity depends on the amount of liquid crystal accessible to the meniscus of the film during the drawing process. Several models are discussed that describe these effects. PMID:12636700

  7. Simultaneous velocity and thickness imaging by ultrasonic scan

    Science.gov (United States)

    Hsu, David K.; Fei, Dong; Shannon, Robert E.; Dayal, Vinay

    2001-04-01

    This paper describes a pulse-echo implementation of the simultaneous velocity and thickness scan technique. The technique was used to measure very small changes in thickness and velocity. Special considerations for achieving accurate and reliable thickness and velocity images are discussed in details. The pulse-echo scan method was also demonstrated for three nondestructive evaluation and material characterization problems: (1) composite laminates containing anomalies, (2) thermal barrier coating materials and (3) creep/rupture tested metal specimens.

  8. Reduced orbitofrontal cortical thickness in male adolescents with internet addiction

    OpenAIRE

    Hong, Soon-Beom; Kim, Jae-Won; Choi, Eun-Jung; Kim, Ho-Hyun; Suh, Jeong-Eun; Kim, Chang-Dai; Klauser, Paul; Whittle, Sarah; Yűcel, Murat; Pantelis, Christos; Yi, Soon-Hyung

    2013-01-01

    Background The orbitofrontal cortex (OFC) has consistently been implicated in the pathology of both drug and behavioral addictions. However, no study to date has examined OFC thickness in internet addiction. In the current study, we investigated the existence of differences in cortical thickness of the OFC in adolescents with internet addiction. On the basis of recently proposed theoretical models of addiction, we predicted a reduction of thickness in the OFC of internet addicted individuals....

  9. Bladder Wall Thickness Mapping for Magnetic Resonance Cystography

    OpenAIRE

    Zhao, Yang; Liang, Zhengrong; Zhu, Hongbin; Han, Hao; Duan, Chaijie; Yan, Zengmin; Lu, Hongbing; Gu, Xianfeng

    2013-01-01

    Clinical studies have shown the evidence that the bladder wall thickness is an effective biomarker for bladder abnormalities. The clinical optical cystoscopy, the current gold standard, cannot show the wall thickness. The use of ultrasound by experts may generate some local thickness information, but the information is limited in field-of-view and is user dependent. Recent advances in magnetic resonance (MR) imaging technologies lead MR-based virtual cystoscopy or MR cystography toward a pote...

  10. Sonographic gallbladder wall thickness in normal adult population in Nigeria

    OpenAIRE

    Mohammed, S; Tahir, A.; A Ahidjo; Z Mustapha; Franza O

    2010-01-01

    Aim. The aim of the study was to determine the ultrasonic gallbladder wall thickness in normal adult Nigerians so as to create standards for defining gallbladder abnormalities in Nigerians. Method. Four hundred adults comprising 228 (57%) women and 172 (43%) men aged 16 - 78 years, who had normal clinical history and physical findings, were recruited. The gallbladder wall thickness was obtained in the supine, prone and right anterior oblique positions. Differences in gallbladder wall thick...

  11. Corneal thickness and endothelial density before and after cataract surgery

    OpenAIRE

    Ventura, A.; Walti, R; Bohnke, M

    2001-01-01

    BACKGROUND/AIMS—Deturgescence of the corneal stroma is controlled by the pumping action of the endothelial layer and can be monitored by measurement of central corneal thickness (pachymetry). Loss or damage of endothelial cells leads to an increase in corneal thickness, which may ultimately induce corneal decompensation and loss of vision. Little is known about the effect of moderate reductions in endothelial cell number on the thickness of the corneal stroma. This study aimed to investigate ...

  12. The measurement of lubricant-film thickness using ultrasound

    OpenAIRE

    Dwyer-Joyce, R.S.; Drinkwater, B. W.; Donohoe, C.J.

    2003-01-01

    Ultrasound is reflected from a liquid layer between two solid bodies. This reflection depends on the ultrasonic frequency, the acoustic properties of the liquid and solid, and the layer thickness. If the wavelength is much greater than the liquid-layer thickness, then the response is governed by the stiffness of the layer. If the wavelength and layer thickness are similar, then the interaction of ultrasound with the layer is controlled by its resonant behaviour. This stiffness governed respon...

  13. Structure and paramyosin content of tarantula thick filaments

    OpenAIRE

    1983-01-01

    Muscle fibers of the tarantula femur exhibit structural and biochemical characteristics similar to those of other long-sarcomere invertebrate muscles, having long A-bands and long thick filaments. 9-12 thin filaments surround each thick filament. Tarantula muscle has a paramyosin:myosin heavy chain molecular ratio of 0.31 +/- 0.079 SD. We studied the myosin cross-bridge arrangement on the surface of tarantula thick filaments on isolated, negatively stained, and unidirectionally metal-shadowed...

  14. Lateral Interactions in Monolayer Thick Mercury Films

    Science.gov (United States)

    Kime, Yolanda Jan

    An understanding of lateral adatom-adatom interactions is often an important part of understanding electronic structure and adsorption energetics in monolayer thick films. In this dissertation I use angle-resolved photoemission and thermal desorption spectroscopies to explore the relationship between the adatom-adatom interaction and other characteristics of the adlayer, such as electronic structure, defects, or coexistent structural phases in the adlayer. Since Hg binds weakly to many substrates, the lateral interactions are often a major contribution to the dynamics of the overlayer. Hg adlayer systems are thus ideal for probing lateral interactions. The electronic structures of Hg adlayers on Ag(100), Cu(100), and Cu_3Au(100) are studied with angle-resolved ultraviolet photoemission. The Hg atomic 5d_{5/2} electronic band is observed to split into two levels following adsorption onto some surfaces. The energetic splitting of the Hg 5d_{5/2} level is found to be directly correlated to the adlayer homogeneous strain energy. The existence of the split off level also depends on the order or disorder of the Hg adlayer. The energetics of Hg adsorption on Cu(100) are probed using thermal desorption spectroscopy. Two different ordered adlayer structures are observed for Hg adsorption on Cu(100) at 200 K. Under some adsorption conditions and over a range of exposures, the two phases are seen to coexist on the surface prior to the thermal desorption process. A phase transition from the more dense to the less dense phase is observed to occur during the thermal desorption process. Inherent differences in defect densities are responsible for the observed differences between lateral interactions measured previously with equilibrium (atom beam scattering) and as measured by the non-equilibrium (thermal desorption) technique reported here. Theoretical and experimental evidence for an indirect through-metal interaction between adatoms is also discussed. Although through

  15. Cortical thickness abnormalities in late adolescence with online gaming addiction.

    Directory of Open Access Journals (Sweden)

    Kai Yuan

    Full Text Available Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18 and age-, education- and gender-matched controls (n = 18 were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC, insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction.

  16. CT artefact reduction by signal to thickness calibration function shaping

    Energy Technology Data Exchange (ETDEWEB)

    Vavrik, Daniel, E-mail: daniel.vavrik@utef.cvut.cz [Institute of Experimental and Applied Physics of the Czech Technical University in Prague, Horska 3a/22, 128 00 Prague 2 (Czech Republic); Institute of Theoretical and Applied Mechanics of the Czech Academy of Sciences, Prosecka 76, 190 00 Prague 9 (Czech Republic)

    2011-05-15

    It is frequently a task to calibrate the radiogram intensity in reference to the object thickness/density value. This knowledge is important when the radiographic densitometry, thickness measurements or precise computed tomography are required. Often aluminum is used as calibrating material and processed radiogram of the real object is evaluated as aluminum equivalent. This approach is qualitatively convenient for transmission radiograms; however, certain secondary artefacts remain in CT reconstructions. Fortunately the calibration function can be shaped using only one or two known thickness values of the object investigated. The shaped calibration function obtained produces the right signal to thickness relationship and CT quality is improved when it is applied.

  17. Thickness measurement by using cepstrum ultrasonic signal processing

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Chul; Yoon, Chan Hoon; Choi, Heui Joo [Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Jong Sun [Chungnam National University, Daejeon (Korea, Republic of)

    2014-08-15

    Ultrasonic thickness measurement is a non-destructive method to measure the local thickness of a solid element, based on the time taken for an ultrasound wave to return to the surface. When an element is very thin, it is difficult to measure thickness with the conventional ultrasonic thickness method. This is because the method measures the time delay by using the peak of a pulse, and the pulses overlap. To solve this problem, we propose a method for measuring thickness by using the power cepstrum and the minimum variance cepstrum. Because the cepstrums processing can divides the ultrasound into an impulse train and transfer function, where the period of the impulse train is the traversal time, the thickness can be measured exactly. To verify the proposed method, we performed experiments with steel and, acrylic plates of variable thickness. The conventional method is not able to estimate the thickness, because of the overlapping pulses. However, the cepstrum ultrasonic signal processing that divides a pulse into an impulse and a transfer function can measure the thickness exactly.

  18. The optimisation of absorber thickness for neutron Soller slit collimators

    Energy Technology Data Exchange (ETDEWEB)

    Cussen, L.D. [Victoria Univ. of Technol., Melbourne (Australia). Sch. of Commun. and Inf.

    1998-08-11

    When constructing neutron Soller slit collimators an absorbing layer is applied to the blades. Choice of an optimum absorber thickness becomes more important as the collimator is made shorter or the neutron absorption becomes poorer as occurs for short wavelength neutrons. A quality factor for the performance of Soller slit collimators is proposed and used to determine the optimum thickness of the absorbing layer. The solution to this problem is non analytic but easily coded as a computer program. Sample calculations of optimum thickness are described. A simple formula for the approximate optimum thickness is given. (orig.) 3 refs.

  19. Triaxial MEMS accelerometer with screen printed PZT thick film

    DEFF Research Database (Denmark)

    Hindrichsen, Christian Carstensen; Almind, Ninia Sejersen; Brodersen, Simon Hedegaard;

    2010-01-01

    . In this work integration of a screen printed piezoelectric PZT thick film with silicon MEMS technology is shown. A high bandwidth triaxial accelerometer has been designed, fabricated and characterized. The voltage sensitivity is 0.31 mV/g in the vertical direction, 0.062 mV/g in the horizontal direction......Piezoelectric thick films have increasing interest due to the potential high sensitivity and actuation force for MEMS sensors and actuators. The screen printing technique is a promising deposition technique for realizing piezoelectric thick films in the thickness range from 10-100 mu m...

  20. Ultrasonic metal sheet thickness measurement without prior wave speed calibration

    International Nuclear Information System (INIS)

    Conventional ultrasonic mensuration of sample thickness from one side only requires the bulk wave reverberation time and a calibration speed. This speed changes with temperature, stress, and microstructure, limiting thickness measurement accuracy. Often, only one side of a sample is accessible, making in situ calibration impossible. Non-contact ultrasound can generate multiple shear horizontal guided wave modes on one side of a metal plate. Measuring propagation times of each mode at different transducer separations, allows sheet thickness to be calculated to better than 1% accuracy for sheets of at least 1.5 mm thickness, without any calibration. (paper)

  1. Thickness measurement by using cepstrum ultrasonic signal processing

    International Nuclear Information System (INIS)

    Ultrasonic thickness measurement is a non-destructive method to measure the local thickness of a solid element, based on the time taken for an ultrasound wave to return to the surface. When an element is very thin, it is difficult to measure thickness with the conventional ultrasonic thickness method. This is because the method measures the time delay by using the peak of a pulse, and the pulses overlap. To solve this problem, we propose a method for measuring thickness by using the power cepstrum and the minimum variance cepstrum. Because the cepstrums processing can divides the ultrasound into an impulse train and transfer function, where the period of the impulse train is the traversal time, the thickness can be measured exactly. To verify the proposed method, we performed experiments with steel and, acrylic plates of variable thickness. The conventional method is not able to estimate the thickness, because of the overlapping pulses. However, the cepstrum ultrasonic signal processing that divides a pulse into an impulse and a transfer function can measure the thickness exactly.

  2. Quantitative X-ray fluorescence analysis of samples of less than 'infinite thickness': Difficulties and possibilities

    International Nuclear Information System (INIS)

    X-ray fluorescence spectrometry due to its nondestructive nature is widely applied in analysis of single layers and multiple layer films (e.g. semiconductors, electrooptic and solar cell devices, coatings, corrosion and paint layers), individual particles (airborne, fly ash, gunshot residue particles, etc.), art and archeological objects (manuscripts, paintings, icons) and many others. Quantitative analysis of these materials, frequently classified as samples of less than infinite thickness (thin or intermediate-thickness samples), required applying adequate matrix correction methods taking into account complex dependence of analyte fluorescent radiation intensity on full matrix composition and sample thickness. In this article, the matrix correction methods including fundamental parameters, Monte Carlo simulations, influence coefficients algorithms and methods based on X-ray transmission measurements are reviewed. The difficulties in the analysis of single layer and multiple layer films and the accuracy of fundamental parameter methods in simultaneous determination of their thickness and composition are discussed. The quantitative analysis of individual particles and inhomogeneous and/or complex structure materials using fundamental parameter and Monte Carlo simulation methods in micro-beam X-ray fluorescence spectrometry are also reviewed. Some references are devoted to the analysis of light matrix samples, e.g. geological, environmental and biological samples, in which undetectable low-Z elements are present (so-called 'dark matrix') using backscattered fundamental parameter methods. Since the samples of less than infinite thickness are partially transparent for X-ray beams, the transmission measurements present possibilities that are unattainable for bulk samples. Thus, the emission-transmission method and also new instruments allowing measurements of the primary X-ray beam transmitted through the sample together with measurements of X-ray fluorescence

  3. An Integrated Observational and Model Synthesis Approach to Examine Dominant Environmental Controls on Active Layer Thickness

    Science.gov (United States)

    Atchley, A. L.; Coon, E.; Painter, S. L.; Harp, D. R.; Wilson, C. J.

    2015-12-01

    The active layer thickness (ALT) - the annual maximum depth of soil with above 0°C temperatures - in part determines the volume of carbon-rich stores available for decomposition and therefore potential greenhouse gas release into the atmosphere from Arctic tundra. However, understanding and predicting ALT in polygonal tundra landscapes is difficult due to the complex nature of hydrothermal atmospheric-surface-subsurface interactions in freezing/thawing soil. Simply deconvolving effects of single environmental controls on ALT is not possible with measurements alone as processes act in concert to drive thaw depth formation. Process-rich models of thermal hydrological dynamics, conversely, are a valuable tool for understanding the dominant controls and uncertainties in predicting permafrost conditions. By integrating observational data with known physical relationships to form process-rich models, synthetic experiments can then be used to explore a breadth of environmental conditions encountered and the effect of each environmental attribute may be assessed. Here a process rich thermal hydrology model, The Advanced Terrestrial Simulator, has been created and calibrated using observed data from Barrow, AK. An ensemble of 1D thermal hydrologic models were simulated that span a range of three environmental factors 1) thickness of organic rich soil, 2) snow depth, and 3) soil moisture content, to investigate the role of each factor on ALT. Results show that organic layer thickness acts as a strong insulator and is the dominant control of ALT, but the strength of the effect of organic layer thickness is also dependent on the saturation state. Using the ensemble results, the effect of peat thickness on ALT was then examined on a 2D domain. This work was supported by LANL Laboratory Directed Research and Development Project LDRD201200068DR and by the The Next-Generation Ecosystem Experiments (NGEE Arctic) project. NGEE-Arctic is supported by the Office of Biological and

  4. The importance of ultrasonographic measurement of peritoneal wall thickness in pediatric chronic peritoneal dialysis patients.

    Science.gov (United States)

    Yavaşcan, Önder; Aksu, Nejat; Alparslan, Caner; Sarıtaş, Serdar; Elmas, Cengiz Han; Eraslan, Ali Nihat; Duman, Soner; Mir, Sevgi

    2015-04-01

    Loss of peritoneal function due to peritoneal fibrosing syndrome (PFS) is a major factor leading to treatment failure in chronic peritoneal dialysis (PD) patients. Although the precise biologic mechanisms responsible for these changes have not been defined, the general assumption is that alterations in peritoneal function are related to structural changes in the peritoneal membrane. Studies of the peritoneal membrane by non-invasive ultrasonography (US) in chronic PD patients are limited. The aim of the present study is to assess the relationship between functional parameters of peritoneum and peritoneal thickness measured by US in children treated by chronic PD. We recruited two groups of patients: 23 subjects (13 females, 10 males) on chronic PD (patient group) and 26 (7 females, 19 males) on predialysis out-patient follow-up (creatinine clearance: 20-60 mL/min/1.73 m(2)) (control group). Age, sex, weight, height, body mass index (BMI), chronic PD duration, episodes of peritonitis and the results of peritoneal equilibration test (PET) were recorded. Hemoglobin (Hb), blood pressure (BP), left ventricular mass index (LVMI) and renal osteodystrophy (ROD) parameters were also obtained. The thickness of the parietal peritoneum was measured by trans-abdominal US in all children. Statistical analyses were performed by using Student's t and Pearson's correlation tests. Mean peritoneal thickness in chronic PD patients (1028.26 ± 157.26 μm) was significantly higher than control patients (786.52 ± 132.33). Mean peritoneal thickness was significantly correlated with mean body height (R(2) = 0.93, p measurement of peritoneal membrane thickness is a simple and non-invasive method in chronic PD children. This diagnostic tool likely enables to assess peritoneal structure and function in these patients. PMID:25594613

  5. A Semi-Analytical Solution for Elastic Analysis of Rotating Thick Cylindrical Shells with Variable Thickness Using Disk Form Multilayers

    Directory of Open Access Journals (Sweden)

    Mohammad Zamani Nejad

    2014-01-01

    Full Text Available Using disk form multilayers, a semi-analytical solution has been derived for determination of displacements and stresses in a rotating cylindrical shell with variable thickness under uniform pressure. The thick cylinder is divided into disk form layers form with their thickness corresponding to the thickness of the cylinder. Due to the existence of shear stress in the thick cylindrical shell with variable thickness, the equations governing disk layers are obtained based on first-order shear deformation theory (FSDT. These equations are in the form of a set of general differential equations. Given that the cylinder is divided into n disks, n sets of differential equations are obtained. The solution of this set of equations, applying the boundary conditions and continuity conditions between the layers, yields displacements and stresses. A numerical solution using finite element method (FEM is also presented and good agreement was found.

  6. Biology of Blood

    Science.gov (United States)

    ... Mail Facebook TwitterTitle Google+ LinkedIn Home Blood Disorders Biology of Blood Overview of Blood Medical Dictionary Also ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  7. Advances in Biological Science.

    Science.gov (United States)

    Oppenheimer, Steven B.; And Others

    1988-01-01

    Reviews major developments in areas that are at the cutting edge of biological research. Areas include: human anti-cancer gene, recombinant DNA techniques for the detection of Huntington disease carriers, and marine biology. (CW)

  8. Biology is simple.

    Science.gov (United States)

    Newman, Tim

    2015-12-30

    This paper explores the potential for simplicity to reveal new biological understanding. Borrowing selectively from physics thinking, and contrasting with Crick's reductionist philosophy, the author argues that greater emphasis on simplicity is necessary to advance biology and its applications.

  9. Engineering scalable biological systems

    OpenAIRE

    Lu, Timothy K.

    2010-01-01

    Synthetic biology is focused on engineering biological organisms to study natural systems and to provide new solutions for pressing medical, industrial, and environmental problems. At the core of engineered organisms are synthetic biological circuits that execute the tasks of sensing inputs, processing logic, and performing output functions. In the last decade, significant progress has been made in developing basic designs for a wide range of biological circuits in bacteria, yeast, and mammal...

  10. Systems interface biology

    OpenAIRE

    Francis J Doyle; Stelling, Jörg

    2006-01-01

    The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Henc...

  11. Biological Races in Humans

    OpenAIRE

    Templeton, Alan R.

    2013-01-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two m...

  12. Milky Way's thick and thin disk: Is there a distinct thick disk?

    Science.gov (United States)

    Kawata, D.; Chiappini, C.

    2016-09-01

    This article is based on our discussion session on Milky Way models at the 592 WE-Heraeus Seminar, Reconstructing the Milky Way's History: Spectroscopic Surveys, Asteroseismology and Chemodynamical Models. The discussion focused on the following question: "Are there distinct thick and thin disks?". The answer to this question depends on the definition one adopts for thin and thick disks. The participants of this discussion converged to the idea that there are at least two different types of disks in the Milky Way. However, there are still important open questions on how to best define these two types of disks (chemically, kinematically, geometrically or by age?). The question of what is the origin of the distinct disks remains open. The future Galactic surveys which are highlighted in this conference should help us answering these questions. The almost one-hour debate involving researchers in the field representing different modelling approaches (Galactic models such as TRILEGAL, Besançon and Galaxia, chemical evolution models, extended distribution functions method, chemodynamics in the cosmological context, and self-consistent cosmological simulations) illustrated how important is to have all these parallel approaches. All approaches have their advantages and shortcomings (also discussed), and different approaches are useful to address specific points that might help us answering the more general question above.

  13. Fires and Thick Smoke Across Southeast Asia

    Science.gov (United States)

    2007-01-01

    Vehicles and power plants are not the only sources of air pollution and greenhouses gases: fires contribute, too. In the Northern Hemisphere spring, which is the end of dry season across much of Southeast Asia, thousands of fires burn each year as people clear cropland and pasture in anticipation of the upcoming wet (growing) season. Intentional fires also escape people's control and burn into adjacent forest. The smoke from these fires crosses the Pacific Ocean, affecting climate far away. This dramatic photo-like image of fires and smoke in Southeast Asia was captured on April 2, 2007, by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite. MODIS detected hundreds, possibly thousands of fires (marked in red), burning in Thailand, Laos, Vietnam, and China. Thick smoke hides nearly all of Laos, where the highest concentration of fires is located. In southern China and northern Vietnam, the smoke has sunk into the valleys that crisscross the mountainous terrain; only the highest ridgelines, which appear dark green, emerge from the blanket of smoke. The smoke sails above a bank of clouds at upper right as a dingy, yellowish haze. Fires have been burning in the region for more than month, as shown by the high carbon monoxide levels observed by NASA's MOPITT sensor during March 2007. In addition to carbon dioxide and other greenhouse gases, fires produce tiny particles of incompletely burned, or charred, carbon. According to research published in mid-March 2007 in the Journal of Geophysical Research, significant amounts of this black carbon travel across the Pacific Ocean to North America at altitudes above 2 kilometers. In spring 2004, between 25-35 gigatons (roughly 55 to 77 million pounds) of black carbon crossed the Pacific and entered skies over western North America between March 26 and April 25; nearly 75 percent of it came from Asia. (Smoke and other pollution have no respect for borders; for example, scientists have also

  14. Upgrading Undergraduate Biology Education

    Science.gov (United States)

    Musante, Susan

    2011-01-01

    On many campuses throughout the country, undergraduate biology education is in serious need of an upgrade. During the past few decades, the body of biological knowledge has grown exponentially, and as a research endeavor, the practice of biology has evolved. Education research has also made great strides, revealing many new insights into how…

  15. Biology Myth-Killers

    Science.gov (United States)

    Lampert, Evan

    2014-01-01

    "Biology Myth-Killers" is an activity designed to identify and correct common misconceptions for high school and college introductory biology courses. Students identify common myths, which double as biology misconceptions, and use appropriate sources to share the "truth" about the myths. This learner-centered activity is a fun…

  16. Influence of biofilm thickness on micropollutants removal in nitrifying MBBRs

    OpenAIRE

    Torresi, Elena; Andersen, Henrik Rasmus; Smets, Barth F.; Plósz, Benedek G.; Christensson, M.

    2015-01-01

    The removal of pharmaceuticals was investigated in nitrifying Moving Bed Biofilm Reactors (MBBRs) containing carriers with different biofilm thicknesses. The biofilm with the thinnest thickness was found to have the highest nitrification and biotransformation rate for some key pharmaceuticals. Microbial analysis revealed a different relative abundance of nitrifying guilds in the different carriers, suggesting the importance of nitrite oxidizing bacteria in removal of micropollutants.

  17. Estimate of shock thickness based on entropy production

    Science.gov (United States)

    Thompson, P. A.; Strock, T. W.; Lim, D. S.

    1983-01-01

    The shock thickness is estimated for a stationary shock in an ideal gas by equating the internal entropy production to the entropy increase found from the Rankine-Hugoniot equation. For elementary assumed profiles, the thickness is expressed by a simple formula. For realistic dependence of viscosity on temperature, results are in qualitative agreement with experiment.

  18. Pelvic floor muscle thickness measured by perineal ultrasonography

    DEFF Research Database (Denmark)

    Bernstein, Inge Thomsen; Juul, N; Grønvall, S;

    1991-01-01

    Pelvic floor muscle thickness was assessed in nine healthy female physiotherapists by perineal sonography. All measurements were performed as triple-measurements. The aims were to assess the reliability of the measurements and to establish a reference material. The muscle thickness at rest...

  19. Mortality by Level of Emphysema and Airway Wall Thickness

    DEFF Research Database (Denmark)

    Johannessen, Ane; Skorge, Trude Duelien; Bottai, Matteo;

    2013-01-01

    There is limited knowledge of the prognostic value of quantitative computed tomography (CT) measures of emphysema and airway wall thickness (AWT) on mortality.......There is limited knowledge of the prognostic value of quantitative computed tomography (CT) measures of emphysema and airway wall thickness (AWT) on mortality....

  20. Determination of thin layer thickness from alpha particle energy spectra

    Energy Technology Data Exchange (ETDEWEB)

    Hnatowicz, V.; Kvitek, J. (Ceskoslovenska Akademie Ved, Prague. Ustav pro Elektrotechniku); Rybka, V.; Krejci, P. (Tesla, Prague (Czechoslovakia). Vyzkumny Ustav pro Sdelovaci Techniku); Pelikan, L. (Ceske Vysoke Uceni Technicke, Prague (Czechoslovakia). Fakulta Elektrotechnicka); Mikusik, P. (Ceskoslovenska Akademie Ved, Prague. Ustav Fyzikalni Chemie a Elektrochemie J. Heyrovskeho)

    1982-10-01

    A method which uses alpha particles from the /sup 10/B(n,alpha)/sup 7/Li nuclear reaction for the determination of surface layer thicknesses is described and experimentally checked. The thickness measurements can be performed on samples implanted with boron.

  1. Origami-Inspired Folding of Thick, Rigid Panels

    Science.gov (United States)

    Trease, Brian P.; Thomson, Mark W.; Sigel, Deborah A.; Walkemeyer, Phillip E.; Zirbel, Shannon; Howell, Larry; Lang, Robert

    2014-01-01

    To achieve power of 250 kW or greater, a large compression ratio of stowed-to-deployed area is needed. Origami folding patterns were used to inspire the folding of a solar array to achieve synchronous deployment; however, origami models are generally created for near-zero-thickness material. Panel thickness is one of the main challenges of origami-inspired design. Three origami-inspired folding techniques (flasher, square twist, and map fold) were created with rigid panels and hinges. Hinge components are added to the model to enable folding of thick, rigid materials. Origami models are created assuming zero (or near zero) thickness. When a material with finite thickness is used, the panels are required to bend around an increasingly thick fold as they move away from the center of the model. The two approaches for dealing with material thickness are to use membrane hinges to connect the panels, or to add panel hinges, or hinges of the same thickness, at an appropriate width to enable folding.

  2. Tube wall thickness guage for hot stretch reducer

    International Nuclear Information System (INIS)

    A new system of tube wall thickness gauge for seamless tube on hot stretch reducing-mill is reported. The system adapts two methods using gamma rays. One is a new method measuring double wall thickness of tube another is a known method measuring mean value of cross section of tube. (author)

  3. Thickness measurement of A-1 reactor caisson tube walls

    International Nuclear Information System (INIS)

    The equipment is described of measuring the thickness of caisson pipes built in the Bohunice A-1 reactor. The pulse-type ultrasonic thickness gauge is based on the reflection method using the double probe. The measurement accuracy is 0.1 mm. (J.B.)

  4. Ultrasonic thickness measurement criteria in thinned pipe management program

    International Nuclear Information System (INIS)

    Credibility of thickness data is very important in the thinned pipe management program. This report presents following criteria; thickness measurement for each pipe component type, wear and wear rate calculation, and remaining service life assessment of thinned pipe component. And, the necessary items should be contained in the inspection report are presented

  5. On-Line thickness measurement in pipes by Gamma radiograph

    International Nuclear Information System (INIS)

    Corrosion in the pipes and remaining wall thickness measurements are the major concern in the piping service lifetime. Ultrasonic is the most common tool in measuring the wall thickness of the pipe. Although the test is relatively simple and fast, but this method is a local point determining method which requires removal of insulation and local surface preparation. Radiography methods (tangential and density evaluation ) are other techniques for thickness loss evaluation. In this investigation, the thickness profile of pipes, with 270 mm in diameter and 7.4-28.5 mm in thickness was determined by the radiograph density measurements nd the use of an Ir-192 gamma source. Some formulas were derived and suggested in this respect by considering the optical density of radiographs in different thicknesses and exposures. It was concluded that thickness loss of 10,20 and 50 percent of wall thickness, corrosion area and corrosion type in insulated and non-insulated gas carrying pipes can be detected by this method. Area of corrosion zone and corrosion type can also be shown in this technique

  6. Sputtering of Thick Deuterium Films by KeV Electrons

    DEFF Research Database (Denmark)

    Thestrup Nielsen, Birgitte; Svendsen, Winnie Edith; Schou, Jørgen;

    1994-01-01

    Sputtering of thick films of solid deuterium up to several μm by keV electrons is reported for the first time. The sputtering yield increases within a narrow range of thicknesses around 1.6 μm by about 2 orders of magnitude for 1.5 keV electrons. A similar behavior has not been observed for ion...

  7. Measuring the Thickness of a Transparent Ring with a Laser

    Science.gov (United States)

    Leung, Alfred F.

    2007-01-01

    There seems to be no reasonable way to measure the thickness of a narrow-mouth glass bottle. One can measure the outer and inner diameters of the mouth with a ruler or a pair of calipers and then calculate the thickness. However, this measurement might be interfered with by the threads at the mouth. Furthermore, it is uncertain whether the…

  8. Asphalt as biological shielding against fusion neutrons

    International Nuclear Information System (INIS)

    For fusion experiments, thick biological radiation protection shields are necessary due to the deep penetration capability of the 14 MeV neutrons. A (D,T) neutron generator with a moderate output of around 1012 n/sec requires a concrete shielding of a wall thickness of 2 meters laterally and at the top of an experimental assembly. The cost for this biological shield may exceed the cost for most of the equipment for a fusion and/or hybrid experimental installation. Particularly, in Saudi Arabia, asphalt is very cheap and available in bulk quantities. As it is rich in hydrogen and carbon, it is worthwhile to investigate its shielding potential against fusion neutron. In the present work different biological shield configurations of asphalt at the wall of the experimental cavity for a research program being undertaken in Saudi Arabia, are investigated. The experimental cavity is approximated by a sphere of 5 meters radius. The yield of the neutron generator is taken as 1012 - 14 MeV - neutron/sec

  9. Synthetic biological networks

    International Nuclear Information System (INIS)

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  10. Barium titanate thick films prepared by screen printing technique

    Directory of Open Access Journals (Sweden)

    Mirjana M. Vijatović

    2010-06-01

    Full Text Available The barium titanate (BaTiO3 thick films were prepared by screen printing technique using powders obtained by soft chemical route, modified Pechini process. Three different barium titanate powders were prepared: i pure, ii doped with lanthanum and iii doped with antimony. Pastes for screen printing were prepared using previously obtained powders. The thick films were deposited onto Al2O3 substrates and fired at 850°C together with electrode material (silver/palladium in the moving belt furnace in the air atmosphere. Measurements of thickness and roughness of barium titanate thick films were performed. The electrical properties of thick films such as dielectric constant, dielectric losses, Curie temperature, hysteresis loop were reported. The influence of different factors on electrical properties values was analyzed.

  11. Influence of thickness on properties of plasticized oat starch films

    Directory of Open Access Journals (Sweden)

    Melicia Cintia Galdeano

    2013-08-01

    Full Text Available The aim of this study was to investigate the effect of thickness (between 80 and 120 µm on apparent opacity, water vapor permeability and mechanical properties (tensile and puncture of oat starch films plasticized with glycerol, sorbitol, glycerol:sorbitol mixture, urea and sucrose. Films were stored under 11, 57, 76 and 90% relative humidity (RH to study the mechanical properties. It was observed that the higher the thickness, the higher was the opacity values. Films without the plasticizer were more opaque in comparison with the plasticized ones. Glycerol:sorbitol films presented increased elongation with increasing thickness at all RH. Puncture force showed a strong dependence on the film thickness, except for the films plasticized with sucrose. In general, thickness did not affect the water permeability.

  12. Use of ground-penetrating radar for asphalt thickness determination

    Science.gov (United States)

    Choubane, Bouzid; Fernando, Emmanuel; Ross, Stephen C.; Dietrich, Bruce T.

    2003-07-01

    A computer program, called TERRA (Thickness Evaluation of Roads by RAdar) was recently developed for estimating pavement layer thicknesses from ground penetrating radar (GPR) data. This program incorporates decision criteria for automated detection of layer interfaces, computation of layer thicknesses and a segmentation algorithm for delineating segments based on layer thicknesses. The Florida Department of Transportation (FDOT) initiated the present field study for an initial assessment of TERRA. Radar and core data were collected from several flexible pavement sections of Florida's roadway system. These sites were selected to represent the present Florida in-place mixes (Superpave and Marshall mixtures) and different asphalt layer thicknesses, which varied from approximately 50 to 300 mm (2 to 12 in). Radar data were collected at both highway speeds and in stationary mode. This paper presents a description of the data collection effort as well as the subsequent analysis and findings.

  13. Study on Thickness Effect of Three-Point-Bend Specimen

    Science.gov (United States)

    Kikuchi, Masanori; Ishihara, Takehito

    The thickness effect of a three-point-bend (3PB) specimen on dimple fracture behavior is studied experimentally and numerically. At first, fracture toughness tests were conducted using 3PB specimens of different thicknesses. Fracture toughness values and R-curves are obtained, and the thickness effect is discussed. Using scanning electron microscopy (SEM), dimple fracture surfaces are observed precisely. It is found that the thickness effect appears clearly in the void growth process. Finite element (FEM) analyses are conducted based on these experimental data. Using Gurson’s constitutive equation, the nucleation and growth of voids during the dimple fracture process are simulated. The distribution patterns of stress triaxiality and the crack growth process are obtained. The results show a good agreement with experimental ones qualitatively. The effects of specimen thickness on R-curves are explained well on the basis of these numerical simulations.

  14. Computational systems chemical biology.

    Science.gov (United States)

    Oprea, Tudor I; May, Elebeoba E; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology (SCB) (Nat Chem Biol 3: 447-450, 2007).The overarching goal of computational SCB is to develop tools for integrated chemical-biological data acquisition, filtering and processing, by taking into account relevant information related to interactions between proteins and small molecules, possible metabolic transformations of small molecules, as well as associated information related to genes, networks, small molecules, and, where applicable, mutants and variants of those proteins. There is yet an unmet need to develop an integrated in silico pharmacology/systems biology continuum that embeds drug-target-clinical outcome (DTCO) triplets, a capability that is vital to the future of chemical biology, pharmacology, and systems biology. Through the development of the SCB approach, scientists will be able to start addressing, in an integrated simulation environment, questions that make the best use of our ever-growing chemical and biological data repositories at the system-wide level. This chapter reviews some of the major research concepts and describes key components that constitute the emerging area of computational systems chemical biology.

  15. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B

    2016-01-01

    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  16. Choroidal thickness after intravitreal ranibizumab injections for choroidal neovascularization

    Directory of Open Access Journals (Sweden)

    Ellabban AA

    2012-05-01

    Full Text Available Abdallah A Ellabban, Akitaka Tsujikawa, Ken Ogino, Sotaro Ooto, Kenji Yamashiro, Akio Oishi, Nagahisa YoshimuraDepartment of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, JapanPurpose: To study changes in choroidal thickness with ranibizumab treatment for choroidal neovascularization (CNV.Design: Prospective case series.Methods: This prospective study consisted of 60 CNV-affected eyes of 60 patients treated with intravitreal injections of ranibizumab using an on-demand protocol after an initial loading phase. The eyes studied included 20 with age-related macular degeneration (AMD, 20 with polypoidal choroidal vasculopathy (PCV, and 20 with myopic CNV. In the eyes with AMD and PCV, choroidal thickness at the fovea was measured with optical coherence tomography using enhanced depth imaging. In eyes with myopic CNV, the choroidal thickness was measured using standard optical coherence tomography without the enhanced depth imaging technique.Results: With ranibizumab treatment, central retinal thickness decreased significantly (P < 0.001 and visual acuity improved significantly (P < 0.001. However, central choroidal thickness (167.2 ± 108.3 µm showed no significant change at 1 month after the loading phase (165.2 ± 107.8 µm, P = 0.120 or at final examination (164.8 ± 107.7 µm, P = 0.115. At baseline, central retinal thickness in eyes with AMD was significantly greater that those with PCV (P = 0.005 or high myopia (P = 0.029. However, central choroidal thickness in eyes with myopic CNV was significantly thinner than in eyes with AMD (P < 0.001 or PCV (P < 0.001. In each type of disease, there was no significant change in central choroidal thickness with ranibizumab treatment.Conclusion: The effect of ranibizumab on the choroidal thickness is minimal, if any.Keywords: choroidal thickness, ranibizumab, optical coherence tomography

  17. Contact resistance and overlapping capacitance in flexible sub-micron long oxide thin-film transistors for above 100 MHz operation

    Energy Technology Data Exchange (ETDEWEB)

    Münzenrieder, Niko, E-mail: muenzenrieder@ife.ee.ethz.ch; Salvatore, Giovanni A.; Petti, Luisa; Zysset, Christoph; Büthe, Lars; Vogt, Christian; Cantarella, Giuseppe; Tröster, Gerhard [Electronics Laboratory Swiss Federal Institute of Technology (ETH) Zürich, Gloriastrasse 35, 8092 Zürich (Switzerland)

    2014-12-29

    In recent years new forms of electronic devices such as electronic papers, flexible displays, epidermal sensors, and smart textiles have become reality. Thin-film transistors (TFTs) are the basic blocks of the circuits used in such devices and need to operate above 100 MHz to efficiently treat signals in RF systems and address pixels in high resolution displays. Beyond the choice of the semiconductor, i.e., silicon, graphene, organics, or amorphous oxides, the junctionless nature of TFTs and its geometry imply some limitations which become evident and important in devices with scaled channel length. Furthermore, the mechanical instability of flexible substrates limits the feature size of flexible TFTs. Contact resistance and overlapping capacitance are two parasitic effects which limit the transit frequency of transistors. They are often considered independent, while a deeper analysis of TFTs geometry imposes to handle them together; in fact, they both depend on the overlapping length (L{sub OV}) between source/drain and the gate contacts. Here, we conduct a quantitative analysis based on a large number of flexible ultra-scaled IGZO TFTs. Devices with three different values of overlap length and channel length down to 0.5 μm are fabricated to experimentally investigate the scaling behavior of the transit frequency. Contact resistance and overlapping capacitance depend in opposite ways on L{sub OV}. These findings establish routes for the optimization of the dimension of source/drain contact pads and suggest design guidelines to achieve megahertz operation in flexible IGZO TFTs and circuits.

  18. Sub-micron gap in-plane micromechanical resonators based on low-temperature amorphous silicon thin-films on glass substrates

    Science.gov (United States)

    Gualdino, A.; Gaspar, J.; Chu, V.; Conde, J. P.

    2015-07-01

    In this work, high-frequency bulk mode resonators made from low stress hydrogenated amorphous silicon (a-Si:H) thin-films are demonstrated. The microelectromechanical structures are fabricated using surface micromachining techniques at a maximum processing temperature of 175 °C on glass substrates. The silicon thin-film based resonators presented here are temperature compatible with post processing on standard CMOS. The resonators are capacitively driven and sensed across 400 nm air gaps. A proof of concept design consisting of a 200 µm side length square has been selectively excited in the Lamé-mode at a characteristic vibration frequency of 13.64 MHz. The quality factor of the resonators is in the 103 range and the motional resistance was measured to be approximately 21.8 MΩ at a DC bias voltage of 40 V.

  19. Sub-micron absolute distance measurements in sub-millisecond times with dual free-running femtosecond Er fiber-lasers.

    Science.gov (United States)

    Liu, Tze-An; Newbury, Nathan R; Coddington, Ian

    2011-09-12

    We demonstrate a simplified dual-comb LIDAR setup for precision absolute ranging that can achieve a ranging precision of 2 μm in 140 μs acquisition time. With averaging, the precision drops below 1 μm at 0.8 ms and below 200 nm at 20 ms. The system can measure the distance to multiple targets with negligible dead zones and a ranging ambiguity of 1 meter. The system is much simpler than a previous coherent dual-comb LIDAR because the two combs are replaced by free-running, saturable-absorber-based femtosecond Er fiber lasers, rather than tightly phase-locked combs, with the entire time base provided by a single 10-digit frequency counter. Despite the simpler design, the system provides a factor of three improved performance over the previous coherent dual comb LIDAR system. PMID:21935219

  20. Design and evaluation of new color-corrected rigid endomicroscopic high NA GRIN-objectives with a sub-micron resolution and large field of view.

    Science.gov (United States)

    Matz, Gregor; Messerschmidt, Bernhard; Gross, Herbert

    2016-05-16

    We demonstrate new GRIN-based endomicroscopic objectives for high resolution single photon fluorescence imaging modalities. Two endoscopic optical design approaches are presented in detail utilizing firstly diffractive and secondly refractive optical elements for the color correction in a spectral range from 488 nm to 550 nm. They are compared with their precursor device experimentally and by simulation. Inherent aberrations for off-axis field points could be lowered remarkably compared with the values of the state-of-the-art system by increasing the intrinsic optical complexity but maintaining the outer spatial dimensions. As a result, those presented objectives predict a diffraction-limited imaging of objects up to 300 μm in diameter with a numerical aperture of 0.8 while keeping an overall outer diameter of the assembly at 1.4 mm. Lastly, confocal fluorescence imaging experiments focus on the comparison between the numerical predicted and the practically achieved quality parameters. PMID:27409921

  1. Aerosol physical properties and processes in the lower marine boundary layer: a comparison of shipboard sub-micron data from ACE-1 and ACE-2

    OpenAIRE

    Bates, Timothy S.; Quinn, Patricia K.; Covert, David S.; Coffman, Derek J; Johnson, James E.; Wiedensohler, Alfred

    2011-01-01

    The goals of the IGAC Aerosol Characterization Experiments (ACE) are to determine and understand the properties and controlling processes of the aerosol in a globally representative range of natural and anthropogenically perturbed environments. ACE-1 was conducted in the remote marine atmosphere south of Australia while ACE-2 was conducted in the anthropogenically modified atmosphere of the Eastern North Atlantic. In-situ shipboard measurements from the RV Discoverer(ACE-1) and the RV Profess...

  2. Contact resistance and overlapping capacitance in flexible sub-micron long oxide thin-film transistors for above 100 MHz operation

    Science.gov (United States)

    Münzenrieder, Niko; Salvatore, Giovanni A.; Petti, Luisa; Zysset, Christoph; Büthe, Lars; Vogt, Christian; Cantarella, Giuseppe; Tröster, Gerhard

    2014-12-01

    In recent years new forms of electronic devices such as electronic papers, flexible displays, epidermal sensors, and smart textiles have become reality. Thin-film transistors (TFTs) are the basic blocks of the circuits used in such devices and need to operate above 100 MHz to efficiently treat signals in RF systems and address pixels in high resolution displays. Beyond the choice of the semiconductor, i.e., silicon, graphene, organics, or amorphous oxides, the junctionless nature of TFTs and its geometry imply some limitations which become evident and important in devices with scaled channel length. Furthermore, the mechanical instability of flexible substrates limits the feature size of flexible TFTs. Contact resistance and overlapping capacitance are two parasitic effects which limit the transit frequency of transistors. They are often considered independent, while a deeper analysis of TFTs geometry imposes to handle them together; in fact, they both depend on the overlapping length (LOV) between source/drain and the gate contacts. Here, we conduct a quantitative analysis based on a large number of flexible ultra-scaled IGZO TFTs. Devices with three different values of overlap length and channel length down to 0.5 μm are fabricated to experimentally investigate the scaling behavior of the transit frequency. Contact resistance and overlapping capacitance depend in opposite ways on LOV. These findings establish routes for the optimization of the dimension of source/drain contact pads and suggest design guidelines to achieve megahertz operation in flexible IGZO TFTs and circuits.

  3. Preparation, Characterization and Performances of High Purity Sub-micron RDX%高纯度亚微米级RDX的制备、表征与性能

    Institute of Scientific and Technical Information of China (English)

    陈亚芳; 王保国; 张景林; 高敏

    2010-01-01

    为推广超细炸药的工业应用,以N,N-二甲基甲酰胺(DMF)为溶剂,蒸馏水为非溶剂,采用高压喷射细化技术、连续过滤洗涤和真空冷冻干燥技术制备了单批生产量为1.5kg量级、平均粒径为852.5nm的高纯度亚微米级黑索今(RDX),细化后的亚微米级RDX的纯度高达99.72%.对亚微米级RDX的丙酮不溶物含量、水分及挥发分、熔点、RDX含量、真空安定性等理化性能进行了测试,结果表明,细化后的亚微米级RDX比原料RDX的性能均有不同程度的提高.

  4. Design and results from the APV25, a deep sub-micron CMOS front-end chip for the CMS tracker

    CERN Document Server

    French, M J; Morrissey, Q R; Neviani, A; Turchetta, R; Fulcher, J R; Hall, G; Noah, E; Raymond, M; Cervelli, G; Moreira, P; Marseguerra, G

    2001-01-01

    The APV25 is a 128-channel analogue pipeline chip for the readout of silicon microstrip detectors in the CMS tracker at the LHC. Each channel comprises a low noise amplifier, a 192-cell analogue pipeline and a deconvolution readout circuit. Output data are transmitted on a single differential current output via an analogue multiplexer. The chip is fabricated in a standard 0.25 mu m CMOS process to take advantage of the radiation tolerance, lower noise and power, and high circuit density, Experimental characterisation of this circuit shows full functionality and good performance both in pre- and post- irradiation (20 Mrad) conditions. The measured noise is significantly reduced compared to earlier APV versions. A description of the design and results from measurements prior to irradiation are presented. (9 refs).

  5. From aqueous metal-solutions to sub-micron powders by a chemical reduction process and ods-products by co-precipitation

    International Nuclear Information System (INIS)

    Different metal-powders like Cu, Ni and precious metals like Ag, Au, Pt or Pd can be produced by adding a suitable reducing agent to an aqueous metal solution. In some cases it is also possible to produce homogeneous solid solution powders. The particle-sizes can be varied in dependence of the reducing parameters like dilution of the solutions and temperature. Submicron powders far below 1 μm as well as particle-sizes up to 5 μm can be produced. A simultaneous co-precipitation of solutions containing the dissolved metal as well as Zr-, or Y-compounds is possible to obtain ODS-materials thereof. Subsequent conventional PM-processing like sintering with simultaneous transformation into oxides and subsequent deformation produces e.g. Zr-, or Y-oxide stabilized materials with suitable mechanical properties. (author)

  6. Sub-micron gap in-plane micromechanical resonators based on low-temperature amorphous silicon thin-films on glass substrates

    International Nuclear Information System (INIS)

    In this work, high-frequency bulk mode resonators made from low stress hydrogenated amorphous silicon (a–Si:H) thin-films are demonstrated. The microelectromechanical structures are fabricated using surface micromachining techniques at a maximum processing temperature of 175 °C on glass substrates. The silicon thin-film based resonators presented here are temperature compatible with post processing on standard CMOS. The resonators are capacitively driven and sensed across 400 nm air gaps. A proof of concept design consisting of a 200 µm side length square has been selectively excited in the Lamé-mode at a characteristic vibration frequency of 13.64 MHz. The quality factor of the resonators is in the 103 range and the motional resistance was measured to be approximately 21.8 MΩ at a DC bias voltage of 40 V. (paper)

  7. Use of buffy coat thick films in detecting malaria parasites in patients with negative conventional thick films

    Institute of Scientific and Technical Information of China (English)

    Chatnapa Duangdee; Noppadon Tangpukdee; Srivicha Krudsood; Polrat Wilairatana

    2012-01-01

    Objective: To determine the frequency of malaria parasite detection from the buffy coat blood ilms by using capillary tube in falciparum malaria patients with negative conventional thick ilms. Methods: Thirty six uncomplicated falciparum malaria patients confirmed by conventional thick and thin films were included in the study. The patients were treated with artemisinin combination therapy at Hospital for Tropical Diseases, Bangkok, Thailand for 28 day. Fingerpricks for conventional blood films were conducted every 6 hours until negative parasitemia, then daily fingerpricks for parasite checks were conducted until the patients were discharged from hospital. Blood samples were also concurrently collected in 3 heparinized capillary tubes at the same time of fingerpricks for conventional blood films when the prior parasitemia was negative on thin films and parasitemia was lower than 50 parasites/200 white blood cells by thick film. The first negative conventional thick films were compared with buffy coat thick films for parasite identification.Results:Out of 36 patients with thick films showing negative for asexual forms of parasites, buffy coat films could detect remaining 10 patients (27.8%) with asexual forms of Plasmodium falciparum. Conclusions: The study shows that buffy coat thick films are useful and can detect malarial parasites in 27.8% of patients whose conventional thick films show negative parasitemia.

  8. Positive association of video game playing with left frontal cortical thickness in adolescents.

    Directory of Open Access Journals (Sweden)

    Simone Kühn

    Full Text Available Playing video games is a common recreational activity of adolescents. Recent research associated frequent video game playing with improvements in cognitive functions. Improvements in cognition have been related to grey matter changes in prefrontal cortex. However, a fine-grained analysis of human brain structure in relation to video gaming is lacking. In magnetic resonance imaging scans of 152 14-year old adolescents, FreeSurfer was used to estimate cortical thickness. Cortical thickness across the whole cortical surface was correlated with self-reported duration of video gaming (hours per week. A robust positive association between cortical thickness and video gaming duration was observed in left dorsolateral prefrontal cortex (DLPFC and left frontal eye fields (FEFs. No regions showed cortical thinning in association with video gaming frequency. DLPFC is the core correlate of executive control and strategic planning which in turn are essential cognitive domains for successful video gaming. The FEFs are a key region involved in visuo-motor integration important for programming and execution of eye movements and allocation of visuo-spatial attention, processes engaged extensively in video games. The results may represent the biological basis of previously reported cognitive improvements due to video game play. Whether or not these results represent a-priori characteristics or consequences of video gaming should be studied in future longitudinal investigations.

  9. Positive Association of Video Game Playing with Left Frontal Cortical Thickness in Adolescents

    Science.gov (United States)

    Kühn, Simone; Lorenz, Robert; Banaschewski, Tobias; Barker, Gareth J.; Büchel, Christian; Conrod, Patricia J.; Flor, Herta; Garavan, Hugh; Ittermann, Bernd; Loth, Eva; Mann, Karl; Nees, Frauke; Artiges, Eric; Paus, Tomas; Rietschel, Marcella; Smolka, Michael N.; Ströhle, Andreas; Walaszek, Bernadetta; Schumann, Gunter; Heinz, Andreas; Gallinat, Jürgen

    2014-01-01

    Playing video games is a common recreational activity of adolescents. Recent research associated frequent video game playing with improvements in cognitive functions. Improvements in cognition have been related to grey matter changes in prefrontal cortex. However, a fine-grained analysis of human brain structure in relation to video gaming is lacking. In magnetic resonance imaging scans of 152 14-year old adolescents, FreeSurfer was used to estimate cortical thickness. Cortical thickness across the whole cortical surface was correlated with self-reported duration of video gaming (hours per week). A robust positive association between cortical thickness and video gaming duration was observed in left dorsolateral prefrontal cortex (DLPFC) and left frontal eye fields (FEFs). No regions showed cortical thinning in association with video gaming frequency. DLPFC is the core correlate of executive control and strategic planning which in turn are essential cognitive domains for successful video gaming. The FEFs are a key region involved in visuo-motor integration important for programming and execution of eye movements and allocation of visuo-spatial attention, processes engaged extensively in video games. The results may represent the biological basis of previously reported cognitive improvements due to video game play. Whether or not these results represent a-priori characteristics or consequences of video gaming should be studied in future longitudinal investigations. PMID:24633348

  10. Bubaline Cholecyst Derived Extracellular Matrix for Reconstruction of Full Thickness Skin Wounds in Rats

    Directory of Open Access Journals (Sweden)

    Poonam Shakya

    2016-01-01

    Full Text Available An acellular cholecyst derived extracellular matrix (b-CEM of bubaline origin was prepared using anionic biological detergent. Healing potential of b-CEM was compared with commercially available collagen sheet (b-CS and open wound (C in full thickness skin wounds in rats. Thirty-six clinically healthy adult Sprague Dawley rats of either sex were randomly divided into three equal groups. Under general anesthesia, a full thickness skin wound (20 × 20 mm2 was created on the dorsum of each rat. The defect in group I was kept as open wound and was taken as control. In group II, the defect was repaired with commercially available collagen sheet (b-CS. In group III, the defect was repaired with cholecyst derived extracellular matrix of bovine origin (b-CEM. Planimetry, wound contracture, and immunological and histological observations were carried out to evaluate healing process. Significantly (P<0.05 increased wound contraction was observed in b-CEM (III as compared to control (I and b-CS (II on day 21. Histologically, improved epithelization, neovascularization, fibroplasia, and best arranged collagen fibers were observed in b-CEM (III as early as on postimplantation day 21. These findings indicate that b-CEM have potential for biomedical applications for full thickness skin wound repair in rats.

  11. Gauging the Galactic thick disk with RR Lyrae stars

    Directory of Open Access Journals (Sweden)

    Cruz G.

    2012-02-01

    Full Text Available In this contribution we present results from the QUEST RR Lyrae Survey of the thick disk. The survey spans ~480 sq. deg. at low latitude |b| < 30°, with multi-epoch VRI observations, obtained with the QUEST-I camera at the 1m Jürgen Stock Schmidt telescope located at the National Astronomical Observatory of Venezuela. This constitutes the first deep RR Lyrae survey of the Galactic thick disk conducted at low galactic latitudes, covering simultaneously a large range in radial (8thick disk structural parameters from in situ RR Lyrae stars having accurate distances (errors <7% and individual reddenings derived from each star’s color curve at minimum light. Moreover, the use of RR Lyrae stars as tracers ensures negligible contamination from the Galactic thin disk. We find a thick disk mean scale height hZ = 0.94 ± 0.11kpc and scale length hR = 3.2 ± 0.4kpc, derived from the vertical and radial mean density profiles of RR Lyrae stars. We also find evidence of thick disk flaring and results that may suggest the thick disk radial density profile shows signs of antitruncation. We discuss our findings in the context of recent thick disk formation models.

  12. Bladder wall thickness mapping for magnetic resonance cystography

    International Nuclear Information System (INIS)

    Clinical studies have shown evidence that the bladder wall thickness is an effective biomarker for bladder abnormalities. Clinical optical cystoscopy, the current gold standard, cannot show the wall thickness. The use of ultrasound by experts may generate some local thickness information, but the information is limited in field-of-view and is user dependent. Recent advances in magnetic resonance (MR) imaging technologies lead MR-based virtual cystoscopy or MR cystography toward a potential alternative to map the wall thickness for the entire bladder. From a high-resolution structural MR volumetric image of the abdomen, a reasonable segmentation of the inner and outer borders of the bladder wall can be achievable. Starting from here, this paper reviews the limitation of a previous distance field-based approach of measuring the thickness between the two borders and then provides a solution to overcome the limitation by an electric field-based strategy. In addition, this paper further investigates a surface-fitting strategy to minimize the discretization errors on the voxel-like borders and facilitate the thickness mapping on the three-dimensional patient-specific bladder model. The presented thickness calculation and mapping were tested on both phantom and human subject datasets. The results are preliminary but very promising with a noticeable improvement over the previous distance field-based approach. (paper)

  13. Bladder wall thickness mapping for magnetic resonance cystography

    Science.gov (United States)

    Zhao, Yang; Liang, Zhengrong; Zhu, Hongbin; Han, Hao; Duan, Chaijie; Yan, Zengmin; Lu, Hongbing; Gu, Xianfeng

    2013-08-01

    Clinical studies have shown evidence that the bladder wall thickness is an effective biomarker for bladder abnormalities. Clinical optical cystoscopy, the current gold standard, cannot show the wall thickness. The use of ultrasound by experts may generate some local thickness information, but the information is limited in field-of-view and is user dependent. Recent advances in magnetic resonance (MR) imaging technologies lead MR-based virtual cystoscopy or MR cystography toward a potential alternative to map the wall thickness for the entire bladder. From a high-resolution structural MR volumetric image of the abdomen, a reasonable segmentation of the inner and outer borders of the bladder wall can be achievable. Starting from here, this paper reviews the limitation of a previous distance field-based approach of measuring the thickness between the two borders and then provides a solution to overcome the limitation by an electric field-based strategy. In addition, this paper further investigates a surface-fitting strategy to minimize the discretization errors on the voxel-like borders and facilitate the thickness mapping on the three-dimensional patient-specific bladder model. The presented thickness calculation and mapping were tested on both phantom and human subject datasets. The results are preliminary but very promising with a noticeable improvement over the previous distance field-based approach.

  14. The effect of unilateral partial edentulism to muscle thickness

    International Nuclear Information System (INIS)

    Teeth and muscle play a very important role for occlusal equilibrium and function.when tooth loss begins ,it may also effect the function of muscle tissues. The thickness of masseter and anterior temporalis muscles were measured bilaterally in 30 healthy fully dentate adults and in 30 unilateral edentulous patients by using ultrasonographic imaging. All scans were carried out by the same radiologist to eliminate the inter-observer difference, using a real time scanner (Toshiba SSA -270A,Japan). A 7.5 MHz linear transducer was used. The effect of age, sex, duration of partial edentulism, unilateral chewing habits of the individuals to the muscle thickness were also evaluated. In all subjects,facial proportion index was also determined. Main purpose of this study was to compare and establish the differences of muscle thickness between dentate and edentulous side in unilateral partial edentulous patients with ultrasonography and to test whether the variation in the thickness of the muscle is related to the variation in the facial and morphology. Ultrasonography revealed a large variation in the thickness of the masseter and temporolis muscles in experimental and controlled groups ,both relaxed and contracted conditions.The thickness of muscles in females was less in both conditions.In experimental group, a high negative correlation was found between the thickness of the masseter muscle and Facial Proportion Index ( FPI) in the females ,however, the statistical analysis showed no significant difference in the males. Also a high negative correlation was found in female control group. There was no statistically significant relationship between unilateral chewing habits and muscle thickness .In this study the duration of partial edentulism did not affect the thickness of the muscle.Further research is required to study muscular atrophy for comparison with total edentulism. (author)

  15. Sonographic gallbladder wall thickness in normal adult population in Nigeria

    Directory of Open Access Journals (Sweden)

    S Mohammed

    2010-12-01

    Full Text Available Aim. The aim of the study was to determine the ultrasonic gallbladder wall thickness in normal adult Nigerians so as to create standards for defining gallbladder abnormalities in Nigerians. Method. Four hundred adults comprising 228 (57% women and 172 (43% men aged 16 - 78 years, who had normal clinical history and physical findings, were recruited. The gallbladder wall thickness was obtained in the supine, prone and right anterior oblique positions. Differences in gallbladder wall thickness were determined using the chi-square test, while the relationship between the ultrasound-measured gallbladder wall thickness and the subjects’ age, sex, height and weight were analysed using the Pearson product moment correlation. Normal ranges and related statistics were estimated and tabulated according to age group and sex. Results. The mean age of the subjects was 32±13.2 years. The mean gallbladder wall thickness range was 1.8 - 2.8 mm±0.5mm. The thickness range for females was 1.7 - 2.7 mm±0.5 mm, and that for males was 1.9 - 2.9 mm±0.5 mm. There was a statistically significant difference (p<0.05 in the mean wall thickness between males and females. The mean body parameters (height, weight of males were significantly greater than those of females (p<0.047, p<0.000 respectively. There was no correlation between gallbladder wall thickness and age and height of subjects (r=0.34, p<0.09. Conclusion. Our study was able to establish population-specific ultrasonic values for gallbladder wall thickness in normal adults that can be reliably used as standard to define gallbladder abnormalities in Nigerians.

  16. Integrated thick-film nanostructures based on spinel ceramics.

    Science.gov (United States)

    Klym, Halyna; Hadzaman, Ivan; Shpotyuk, Oleh; Brunner, Michael

    2014-01-01

    Integrated temperature-humidity-sensitive thick-film structures based on spinel-type semiconducting ceramics of different chemical compositions and magnesium aluminate ceramics were prepared and studied. It is shown that temperature-sensitive thick-film structures possess good electrophysical characteristics in the region from 298 to 358 K. The change of electrical resistance in integrated thick-film structures is 1 order, but these elements are stable in time and can be successfully used for sensor applications. PMID:24670141

  17. Measurement of pipe wall local thickness by combined radiation method

    International Nuclear Information System (INIS)

    Analytical dependences have been studied which describe radiation fluxes registered by the respective detectors during transmission of a collimated beam of penetrating radiation through a tube over its diameter. The dependences are necessary for engineering designs, analysis of accuracy and other characteristics of radioisotope thickness gaUges using the combined method for measurements of tube wall local thickness. Experimental investigations have been carried out with 137Cs and 60Co sources. The dependence, permitting to determine conditions providing with the preset accuracy of tube wall local thickness measurement by the combined method, has been obtained

  18. Thick epitaxial YIG films with narrow FMR linewidth

    OpenAIRE

    Syvorotka, I. I.; Syvorotka, I. M.; Ubizskii, S.B.

    2012-01-01

    The La-doped yttrium iron garnet (YIG) films with thickness up to 130 μm were grown by liquid phase epitaxy (LPE) method. All grown thick films demonstrate “mirror” and “striation” types of surface morphology that depend from film growth temperature and thickness. Addition of B2O3 is favourable to a change the surface morphology into a “mirror” one. The mechanisms of the morphological changes are discussed. It was found that the ferromagnetic resonance (FMR) linewidth appreciably dep...

  19. Calculating thin-bed thickness in frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Jianyang, Y. (Shanghai Offshore Geological Survey Bureau, Ministry of Geology and Minerals, No. 340 Shenjia lu Alley, Pudong District, Shanghai City (CN))

    1991-01-01

    Thin-bed thickness can be quantitatively calculated by using amplitude information when the seismic waves were recorded in simple surface seismic-geological condition and stable shot-receiving condition. However, Seismic waves are rarely recorded on such ideal conditions. In this paper a method for calculating thin-bed thickness with the use of frequency information is proposed as a result of thin-bed model research. This method uses amplitude spectrum values of low frequency contents in seismic frequency spectrum to determine bed thickness error is minutely analyzed which may be caused by thin interbedding and different wavelets. This method is proved feasible.

  20. Pelvic floor muscle thickness measured by perineal ultrasonography

    DEFF Research Database (Denmark)

    Bernstein, Inge Thomsen; Juul, N; Grønvall, S;

    1991-01-01

    Pelvic floor muscle thickness was assessed in nine healthy female physiotherapists by perineal sonography. All measurements were performed as triple-measurements. The aims were to assess the reliability of the measurements and to establish a reference material. The muscle thickness at rest...... and at contraction was 9.4 +/- 0.8 mm and 11.5 +/- 1.1 mm respectively (mean +/- SD). Contraction increased the thickness by 2.2 +/- 0.8 mm or 23 +/- 8%. The intra- and inter observer standard deviation of the estimate was in the range of 4-6%. In conclusion, we find the reliability of the measurements acceptable....

  1. A spectroscopic method for determining thickness of quartz wave plate

    Institute of Scientific and Technical Information of China (English)

    Weiwei Feng; Lihuang Lin; Ligang Chen; Huafeng Zhu; Ruxin Li; Zhizhan Xu

    2006-01-01

    A spectroscopic method to determine thickness of quartz wave plate is presented. The method is based on chromatic polarization interferometry. With the polarization-resolved transmission spectrum (PRTS)curve, the phase retardation of quartz wave plate can be determined at a wide spectral range from 200 to2000 nm obviously. Through accurate judgment of extreme points of PRTS curve at long-wave band, the physical thickness of quartz wave plates can be obtained exactly. We give a measuring example and the error analysis. It is found that the measuring precision of thickness is mainly determined by the spectral resolution of spectrometer.

  2. Simultaneous orientation and thickness mapping in transmission electron microscopy

    International Nuclear Information System (INIS)

    In this paper we introduce an approach for simultaneous thickness and orientation mapping of crystalline samples by means of transmission electron microscopy. We show that local thickness and orientation values can be extracted from experimental dark-field (DF) image data acquired at different specimen tilts. The method has been implemented to automatically acquire the necessary data and then map thickness and crystal orientation for a given region of interest. We have applied this technique to a specimen prepared from a commercial semiconductor device, containing multiple 22 nm technology transistor structures. The performance and limitations of our method are discussed and compared to those of other techniques available

  3. Simultaneous orientation and thickness mapping in transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tyutyunnikov, Dmitry, E-mail: dmitry.tyutyunnikov@uni-ulm.de [Institute for Experimental Physics, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm (Germany); Burak Özdöl, V. [National Center for Electron Microscopy, MS 72-150 Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Koch, Christoph T. [Institute for Experimental Physics, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm (Germany)

    2015-03-15

    In this paper we introduce an approach for simultaneous thickness and orientation mapping of crystalline samples by means of transmission electron microscopy. We show that local thickness and orientation values can be extracted from experimental dark-field (DF) image data acquired at different specimen tilts. The method has been implemented to automatically acquire the necessary data and then map thickness and crystal orientation for a given region of interest. We have applied this technique to a specimen prepared from a commercial semiconductor device, containing multiple 22 nm technology transistor structures. The performance and limitations of our method are discussed and compared to those of other techniques available.

  4. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  5. Foundations of biology

    OpenAIRE

    Sikorav, Jean-Louis; Braslau, Alan; Goldar, Arach

    2014-01-01

    It is often stated that there are no laws in biology, where everything is contingent and could have been otherwise, being solely the result of historical accidents. Furthermore, the customary introduction of fundamental biological entities such as individual organisms, cells, genes, catalysts and motors remains largely descriptive; constructive approaches involving deductive reasoning appear, in comparison, almost absent. As a consequence, both the logical content and principles of biology ne...

  6. Introducing Aquatic Biology

    OpenAIRE

    Kinne, Otto; Browman, Howard I.; Seaman, Matthias

    2007-01-01

    The Inter-Research Science Center (IR) journals Marine Ecology Progress Series (MEPS) and Aquatic Microbial Ecology (AME) have been receiving increasing numbers of high-quality manuscripts that are principally biological, rather than ecological. With regret, we have had to turn these submissions away. Also, leading limnologists have for many years suggested that IR should provide an outlet for top quality articles on freshwater biology and ecology. Aquatic Biology (...

  7. Glycobiology Current Molecular Biology

    OpenAIRE

    Sabire KARAÇALI

    2003-01-01

    Carbohydrate chemistry evolved into carbohydrate biochemistry and gradually into the biology of carbohydrates, or glycobiology, at the end of the last century. Glycobiology is the new research area of modern molecular biology, and it investigates the structure, biosynthesis and biological functions of glycans. The numbers, linkage types (a or b), positions, binding points and functional group differences of monosaccharides create microheterogeneity. Thus, numerous glycoforms with precise stru...

  8. Biological aerosol background characterization

    Science.gov (United States)

    Blatny, Janet; Fountain, Augustus W., III

    2011-05-01

    To provide useful information during military operations, or as part of other security situations, a biological aerosol detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if aerosol particles have viability characteristics. Still, such commercially available biological aerosol detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological aerosol characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological aerosol characteristics to reduce false alarm rates.

  9. The influence of fiber thickness, wall thickness and gap distance on the spiral nanofibrous scaffolds for bone tissue engineering

    International Nuclear Information System (INIS)

    We have developed a 3D nanofibrous spiral scaffold for bone tissue engineering which has shown enhanced cell attachment, proliferation and differentiation compared to traditional cylindrical scaffolds due to the spiral structures and the nanofiber incorporation. Some important parameters of these spiral scaffolds including gap distance, wall thickness and especially fiber thickness are crucial to the performance of the spiral structured scaffolds. In this study, we investigated the fiber thickness, gap distance and wall thickness of the spiral structure on the behavior of osteoblast cells. The human osteoblast cells are seeded on spiral structured scaffolds with various fiber thickness, gap distance and wall thickness and cell attachment, proliferation, differentiation and mineralized matrix deposition on the scaffolds are evaluated. It was found that increasing the thickness of nanofiber layer not only limited the cell infiltration into the scaffolds, but also restrained the osteoblastic cell phenotype development. Moreover, the geometric effect studies indicated that scaffolds with the thinner wall and gap distance 0.2 mm show the best bioactivity for osteoblasts.

  10. Gulf Coast Estimated Thickness of the Middle Miocene Sequence

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  11. Gulf Coast Estimated Thickness of the Upper Miocene Sequence

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  12. Estimated Thickness of the Lower Miocene 1 Sequence, Gulf Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  13. Advantages of PZT thick film for MEMS sensors

    DEFF Research Database (Denmark)

    Hindrichsen, Christian Carstensen; Lou-Moller, R.; Hansen, K.;

    2010-01-01

    For all MEMS devices a high coupling between the mechanical and electrical domain is desired. Figures of merit describing the coupling are important for comparing different piezoelectric materials. The existing figures of merit are discussed and a new figure of merit is introduced for a fair...... comparison of piezoelectric thin and thick films based MEMS devices, as cantilevers, beams, bridges and membranes. Simple analytical modeling is used to define the new figure of merit. The relevant figure of merits is compared for the piezoelectric material of interest for MEMS applications: ZnO, AIN, PZT...... thin film and PZT thick film. It is shown that MEMS sensors with the PZT thick film TF2100 from InSensor A/S have potential for significant higher voltage sensitivities compared to PZT thin film base MEMS sensors when the total thickness of the MEMS cantilever, beam, bridge or membrane is high...

  14. Modeled Thickness of the Overburden Geomodel Unit (obthk_f)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The obthk_f grid represents the modeled thickness of the Overburden geomodel unit at a 500 foot resolution. It is one grid of a geomodel that consists of eleven...

  15. Characteristics of shell thickness in a slab continuous casting mold

    Institute of Scientific and Technical Information of China (English)

    Di-feng Wu; Shu-sen Cheng; Zi-jian Cheng

    2009-01-01

    The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold.A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid (VOF) model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions.The results show that the jet acts a stronger impingement on the shell of narrow face,which causes a zero-increase of shell thickness in a certain range near the impingement point.The thinnest shell on the slab cross-section locates primarily in the center of the narrow face,and secondly near the comer of the wide face.Nozzle optimization can obviously increase the shell thickness and make it more uniform.

  16. Changes on the corneal thickness and curvature after orthokeratology

    Science.gov (United States)

    Mitsui, Iwane; Yamada, Yoshiya

    2004-07-01

    To evaluate the corneal thickness and curvature changes after Orthokeratology contact lens wear, using the ORBSCAN II corneal topography system, corneal thickness and corneal curvature were measured on one hundred and twenty eyes of sixty patients before and after wearing the custom rigid gas permeable contact lenses for Orthokeratology. The contact lenses were specially designed for each eye. The subjects wore the orthokeratology lenses for approximately Four hours with their eyes closed. The corneal thickness of the subjects was increased on fifty-five eyes at not only the peripheral zone but also the center of the cornea. The average increase of central and peripheral corneal thickness was 18 micrometer and 22micrometer, respectively. The mean anterior curvature of corneal surface changed 1.25D. The mean posterior curvature of corneal endothelium side changed 0.75D.

  17. Saturated thickness of the High Plains Aquifer, Colorado, 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data are in support of report DS 472 (Arnold and others, 2009). This data set represents the saturated thickness of the High Plains aquifer within Colorado....

  18. Oblique perforation of thick metallic plates by rigid projectiles

    Institute of Scientific and Technical Information of China (English)

    Xiaowei Chen; Qingming Li; Saucheong Fan

    2006-01-01

    Oblique perforation of thick metallic plates by rigid Drojectiles with various nose shapes is studied in this paper.Two perforation mechanisms,i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose,are considered in the proposed analytical model.It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers,i.e., the impact function,the geometry function of projectile,the non-dimensional thickness of target and the impact obliquity.Explicit formulae are obtained to predict the ballistic limit.residual velocity and directional change for the oblique perforation of thick metallic plates.The proposed model is able to predict the critical condition for the occurrence of ricochet.The proposed model is validated by comparing the predictions with other existing models and independent experimental data.

  19. Charge Distribution Dependency on Gap Thickness of CMS Endcap RPC

    CERN Document Server

    Park, Sung K; Lee, Kyongsei

    2016-01-01

    We report a systematic study of charge distribution dependency of CMS Resistive Plate Chamber (RPC) on gap thickness. Prototypes of double-gap RPCs with six different gap thickness ranging from from 1.0 to 2.0 mm in 0.2-mm steps have been built with 2-mm-thick phenolic high-pressure-laminated plates. The efficiencies of the six gaps are measured as a function of the effective high voltages. We report that the strength of the electric fields of the gap is decreased as the gap thickness is increased. The distributions of charges in six gaps are measured. The space charge effect is seen in the charge distribution at the higher voltages. The logistic function is used to fit the charge distribution data. Smaller charges can be produced within smaller gas gap. But the digitization threshold should be also lowered to utilize these smaller charges.

  20. Bilayer-thickness-mediated interactions between integral membrane proteins

    CERN Document Server

    Kahraman, Osman; Klug, William S; Haselwandter, Christoph A

    2016-01-01

    Hydrophobic thickness mismatch between integral membrane proteins and the surrounding lipid bilayer can produce lipid bilayer thickness deformations. Experiment and theory have shown that protein-induced lipid bilayer thickness deformations can yield energetically favorable bilayer-mediated interactions between integral membrane proteins, and large-scale organization of integral membrane proteins into protein clusters in cell membranes. Within the continuum elasticity theory of membranes, the energy cost of protein-induced bilayer thickness deformations can be captured by considering compression and expansion of the bilayer hydrophobic core, membrane tension, and bilayer bending, resulting in biharmonic equilibrium equations describing the shape of lipid bilayers for a given set of bilayer-protein boundary conditions. Here we develop a combined analytic and numerical methodology for the solution of the equilibrium elastic equations associated with protein-induced lipid bilayer deformations. Our methodology al...

  1. sir-06-5129_thickness_raton_con

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set consists of contours of lines of equal apparent thickness of the Raton Formation, the interval between the tops of the Raton and...

  2. SIR-06-5129_thickness_trinidad_con

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set consists of contours of lines of equal apparent thickness of the Trinidad Sandstone, the interval between the tops of the Trinidad...

  3. sir-06-5129_thickness_vermejo_con

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital geospatial data set consists of contours of lines of equal apparent thickness of the Veremjo Formation, the interval between the tops of the Vermejo...

  4. One-cm-thick Si detector at LHe temperature

    Energy Technology Data Exchange (ETDEWEB)

    Braggio, C. [Dipartimento di Fisica, Universita di Ferrara, Via Saragat 1, 44100 Ferrara (Italy)], E-mail: braggio@pd.infn.it; Bressi, G. [INFN, Sez. di Pavia, Via Bassi 6, 27100 Pavia (Italy); Carugno, G. [INFN, Sez. di Padova, Via Marzolo 8, 35131 Padova (Italy); Galeazzi, G. [Laboratori Nazionali di Legnaro, Via dell' Universita 1, 35020 Legnaro (Italy); Serafin, A. [Dipartimento di Fisica, Universita di Padova, Via Marzolo 8, 35131 Padova (Italy)

    2007-10-11

    A silicon p-i-n diode of thickness 1 cm has been studied experimentally at liquid helium temperature. This preliminary study is aimed at the construction of a much bigger detector to detect low energy neutrino events.

  5. Measurement of liquid crystal film thickness using interferometry

    International Nuclear Information System (INIS)

    Thickness measurements of thin films having thickness less than 1 µm are difficult to obtain by an interferometer. These difficulties arise from the overlap of the fringes from the upper and lower surfaces of the thin films. This paper presents a new methodology that mediates the consequences of this overlap and then implements it with thickness measurements of liquid crystal (LC) thin films. It takes into consideration the properties of light propagation within these films in order to rectify the images obtained from the interferometer. It assumes that the lower fringe pattern is much stronger that the upper one and hence the latter may be ignored. This occurs in situations where thin films are coated on substrates of significantly higher reflectivity, as happens when an LC thin film is coated on a polished iron substrate. The thickness and topography of LC thin films were experimentally measured with this methodology and were compared with measurements taken by an atomic force microscope

  6. Accurate wall thickness measurement using autointerference of circumferential Lamb wave

    International Nuclear Information System (INIS)

    In this paper, a method of accurately measuring the pipe wall thickness by using noncontact air-coupled ultrasonic transducer (NAUT) was presented. In this method, accurate measurement of angular wave number (AWN) is a key technique because the AWN is changes minutely with the wall thickness. An autointerference of the circumferential (C-) Lamb wave was used for accurate measurements of the AWN. Principle of the method was first explained. Modified method for measuring the wall thickness near a butt weld line was also proposed and its accuracy was evaluated within 6 μm error. It was also shown in the paper that wall thickness measurement was accurately carried out beyond the difference among the sensors by calibrating the frequency response of the sensors. (author)

  7. Study of pipe thickness loss using a neutron radiography method

    International Nuclear Information System (INIS)

    The purpose of this preliminary work is to study for thickness changes in objects using neutron radiography. In doing the project, the technique for the radiography was studied. The experiment was done at NUR-2 facility at TRIGA research reactor in Malaysian Nuclear Agency, Malaysia. Test samples of varying materials were used in this project. The samples were radiographed using direct technique. Radiographic images were recorded using Nitrocellulose film. The films obtained were digitized to processed and analyzed. Digital processing is done on the images using software Isee!. The images were processed to produce better image for analysis. The thickness changes in the image were measured to be compared with real thickness of the objects. From the data collected, percentages difference between measured and real thickness are below than 2%. This is considerably very low variation from original values. Therefore, verifying the neutron radiography technique used in this project

  8. Thick Dirac-Nambu-Goto branes on black hole backgrounds

    CERN Document Server

    Czinner, Viktor G

    2014-01-01

    Thickness corrections to static, axisymmetric Dirac-Nambu-Goto branes embedded into spherically symmetric black hole spacetimes with arbitrary number of dimensions are studied. First, by applying a perturbative approximation, it is found that the thick solutions deviate significantly in their analytic properties from the thin ones near the axis of the system, and perturbative approaches around the thin configurations can not provide regular thick solutions above a certain dimension. For the general case, a non-perturbative, numerical approach is applied and regular solutions are obtained for arbitrary brane and bulk dimensions. As a special case, it has been found that 2-dimensional branes are exceptional, as they share their analytic properties with the thin branes rather than the thick solutions of all other dimensions.

  9. Using laser to measure stem thickness and cut weed stems

    DEFF Research Database (Denmark)

    Heisel, T.; Schou, Jørgen; Andreasen, C.;

    2002-01-01

    Stem thickness of the weed Solanum nigrum and the crop sugarbeet was determined with a He-Ne laser using a novel non-destructive technique measuring stem shadow. Thereafter, the stems were cut close to the soil surface with a CO2 laser. Treatments were carried out on pot plants, grown...... in the greenhouse, at two different growth stages, and plant dry matter was measured 2-5 weeks after treatment. The relationship between plant dry weight and laser energy was analysed using two different non-linear dose-response regression models; one model included stem thickness as a variable, the other did not....... A binary model was also tested. The non-linear model incorporating stem thickness described the data best, indicating that it would be possible to optimize laser cutting by measuring stem thickness before cutting. The general tendency was that more energy was needed the thicker the stem. Energy uses...

  10. Generalized thickness of the Minnelusa Formation, Black Hills, South Dakota.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set is a polygon coverage created in ARC/INFO that represents the generalized thickness of the Minnelusa Formation, Black Hills, South Dakota. The...

  11. Saturated thickness of the Minnelusa aquifer, Black Hills, South Dakota.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set is a polygon coverage created in ARC/INFO that represents the saturated thickness of the Minnelusa aquifer, Black Hills area, South Dakota. The...

  12. Total Sediment Thickness of the World's Oceans & Marginal Seas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A digital total-sediment-thickness database for the world's oceans and marginal seas has been compiled by the NOAA National Geophysical Data Center (NGDC). The data...

  13. Sediment Thickness--Pigeon Point to South Monterey Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the sediment-thickness map of the Pigeon Point to South Monterey Bay, California, region. The raster data file is included in...

  14. Properties of thick discs formed in clumpy galaxies

    CERN Document Server

    Inoue, Shigeki

    2014-01-01

    We examine a possible formation scenario of galactic thick discs with numerical simulations. Thick discs have previously been argued to form in clumpy disc phase in the high-redshift Universe, which host giant clumps of <10^9 M_sun in their highly gas-rich discs. We performed SPH simulations using isolated galaxy models for the purpose of verifying whether dynamical and chemical properties of the thick discs formed in such clumpy galaxies are compatible with observations. The results of our simulations seem nearly consistent with observations in dynamical properties such as radial and vertical density profiles, significant rotation velocity lag with height and distributions of orbital eccentricities. In addition, the thick discs in our simulations indicate nearly exponential dependence of azimuthal and vertical velocity dispersions with radius, nearly isothermal kinematics in vertical direction and negligible metallicity gradients in radial and vertical directions. However, our simulations cannot reproduce...

  15. Quantification of retinal layer thickness changes in acute macular neuroretinopathy

    DEFF Research Database (Denmark)

    Munk, Marion R; Beck, Marco; Kolb, Simone;

    2016-01-01

    PURPOSE: To quantitatively evaluate retinal layer thickness changes in acute macular neuroretinopathy (AMN). METHODS: AMN areas were identified using near-infrared reflectance (NIR) images. Intraretinal layer segmentation using Heidelberg software was performed. The inbuilt ETDRS -grid was moved ...

  16. Screen-printed piezoceramic thick films for miniaturised devices

    DEFF Research Database (Denmark)

    Lou-Moeller, R.; Hindrichsen, Christian Carstensen; Thamdrup, Lasse Højlund;

    2007-01-01

    The development towards smaller devices with more functions integrated calls for new and improved manufacturing processes. The screen-printing process is quite well suited for miniaturised and integrated devices, since thick films can be produced in this manner without the need for further...... machining. On the other hand, the process of screen printing thick films involves potential problems of thermal matching and chemical compatibility at the processing temperatures between the functional film, the substrate and the electrodes. As an example of such a miniaturised device, a MEMS accelerometer...... based on PZT thick film will be presented. The design and process flow of this accelerometer has been optimised by means of finite element modelling (FEMLAB (c)). Consequently it has proved possible to eliminate post-processing steps after the screen printing of the PZT thick film....

  17. Estimated Thickness of the Lower Miocene 2 Sequence, Gulf Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  18. Effect of electrode thickness variation on operation of capacitive deionization

    OpenAIRE

    Porada, S.; Bryjak, M.; Wal, van der, A.C.; Biesheuvel, P. M.

    2012-01-01

    In capacitive deionization (CDI) water is desalinated by applying an electrical field between two porous electrodes placed on either side of a spacer channel that transports the aqueous solution. In this work we investigate the equilibrium salt adsorption and the dynamic development of the effluent salt concentration in time, both as function of spacer and electrode thicknesses. The electrode thickness will be varied in a symmetric manner (doubling both electrodes) and in an asymmetric manner...

  19. Toward thick legitimacy: Creating a web of legitimacy for agroecology

    OpenAIRE

    Maywa Montenegro de Wit; Alastair Iles

    2016-01-01

    Abstract Legitimacy is at the heart of knowledge politics surrounding agriculture and food. When people accept industrial food practices as credible and authoritative, they are consenting to their use and existence. With their thick legitimacy, industrial food systems paralyze the growth of alternative agricultures, including agroecology. Questions of how alternative agricultures can attain their own thick legitimacy in order to compete with, and displace, that of industrial food have not yet...

  20. QTLs for stem thickness and strength in rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Lodging resistance has been a key target trait for raising yield potential in rice and it is associated with many component traits such as plant height and stem thickness and strength. etc. While phenotypic selection for lodging resistance has been effective, its genetic basis remains poorly understanding. To understand the genetic basis of stem thickness and strength, and to facilitate genetic improvement of lodging resistance in rice

  1. Numerical Controlled Rolling Process of Thick Metal Plate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Thick metal plate rolling process has become more and more important in building a flat roof of drilling on the bottom at sea. This is because not only the product quality requirement higher and higher but also the marketing competition. To improve the process of thick metal plate rolling and to increase productivity a numerical controlled rolling process is developed, which include the process planning, the mathematical model establishment and the numerical control system development. The process is for ...

  2. Thickness control in structural optimization via a level set method

    OpenAIRE

    Allaire, Grégoire; Jouve, François; Michailidis, Georgios

    2014-01-01

    In the context of structural optimization via a level-set method we propose a framework to handle geometric constraints related to a notion of local thickness. The local thickness is calculated using the signed distance function to the shape. We formulate global constraints using integral functionals and compute their shape derivatives. We discuss diff erent strategies and possible approximations to handle the geometric constraints. We implement our approach in two and three space dimensions ...

  3. Reconstruction of Optical Thickness from Hoffman Modulation Contrast Images

    DEFF Research Database (Denmark)

    Olsen, Niels Holm; Sporring, Jon; Nielsen, Mads;

    2003-01-01

    Hoffman microscopy imaging systems are part of numerous fertility clinics world-wide. We discuss the physics of the Hoffman imaging system from optical thickness to image intensity, implement a simple, yet fast, reconstruction algorithm using Fast Fourier Transformation and discuss the usability...... of the method on a number of cells from a human embryo. Novelty is identifying the non-linearity of a typical Hoffman imaging system, and the application of Fourier Transformation to reconstruct the optical thickness....

  4. Minimum Plate Thickness in High-Speed Craft

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The minimum plate thickness requirements specified by the classification societies for high-speed craft are supposed to ensure adequate resistance to impact loads such as collision with floating objects and objects falling on the deck. The paper presents analytical methods of describing such impact...... phenomena and proposes performance requirements instead of thickness requirements for hull panels in high-speed craft made of different building materials....

  5. A Semi-Automatic Thickness Inspection Technique for Marine Propellers

    Institute of Scientific and Technical Information of China (English)

    M; K; Lam; S; F; Lee; C; S; Lam; W; S; Chow; P; Iovenitti; S; H; Masood

    2002-01-01

    This paper describes the design and development of a Semi-Automatic Precision Caliper System to measure the thickness of an outboard marine engine propeller blade. Several commonly used methods for measuring the thickness of a propeller blade are reviewed in this paper. These include the P rops Scan, 3D Vision System and Black Dog. However, the operating practices and availability of different facilities in industry necessitate a more cost-effect ive approach. An alternative method using a Semi-Auto...

  6. Type I migration in optically thick accretion discs

    OpenAIRE

    Yamada, K; Inaba, S.

    2012-01-01

    We study the torque acting on a planet embedded in an optically thick accretion disc, using global two-dimensional hydrodynamic simulations. The temperature of an optically thick accretion disc is determined by the energy balance between the viscous heating and the radiative cooling. The radiative cooling rate depends on the opacity of the disc. The opacity is expressed as a function of the temperature. We find the disc is divided into three regions that have different temperature distributio...

  7. Effects of Neutron Skin Thickness in Peripheral Nuclear Reactions

    Institute of Scientific and Technical Information of China (English)

    FANG De-Qing; MA Yu-Gang; CAI Xiang-Zhou; TIAN Wen-Dong; WANG Hong-Wei

    2011-01-01

    Effects of neutron skin thickness in peripheral nuclear collisions are investigated using the statistical abrasion ablation (SAA) model. The reaction cross section, neutron (proton) removal cross section, one-neutron (proton) removal cross section as well as their ratios for nuclei with different neutron skin thickness are studied. It is demonstrated that there are good linear correlations between these observables and the neutron skin thickness for neutron-rich nuclei. The ratio between the (one-)neutron and proton removal cross section is found to be the most sensitive observable of neutron skin thickness. Analysis shows that the relative increase of this ratio could be used to determine the neutron skin size in neutron-rich nuclei.%Effects of neutron skin thickness in peripheral nuclear collisions are investigated using the statistical abrasion ablation (SAA ) model.The reaction cross section,neutron (proton) removal cross section,one-neutron (proton) removal cross section as well as their ratios for nuclei with different neutron skin thickness are studied.It is demonstrated that there are good linear correlations between these observables and the neutron skin thickness for neutron-rich nuclei.The ratio between the (one-)neutron and proton removal cross section is found to be the most sensitive observable of neutron skin thickness.Analysis shows that the relative increase of this ratio could be used to determine the neutron skin size in neutron-rich nuclei.Determining the size and shape of a nucleus is one of the most important subjects since the discovery of atomic nuclei.The rms radii of the neutron (rn) and proton (rp) density distributions are among the most prominent observables for this purpose.Studies for stable nuclei have shown that the nuclear radii are proportional to A1/3,with A being the nuclear mass number.Meanwhile,the density distributions of neutrons and protons in stable nuclei are very similar.

  8. Crustal-thickness variations in the central Andes

    Science.gov (United States)

    Beck, Susan L.; Zandt, George; Myers, Stephen C.; Wallace, Terry C.; Silver, Paul G.; Drake, Lawrence

    1996-05-01

    We estimated the crustal thickness along an east-west transect across the Andes at lat 20°S and along a north-south transect along the eastern edge of the Altiplano from data recorded on two arrays of portable broadband seismic stations (BANJO and SEDA). Waveforms of deep regional events in the downgoing Nazca slab and teleseismic earthquakes were processed to isolate the P-to-S converted phases from the Moho in order to compute the crustal thickness. We found crustal-thickness variations of nearly 40 km across the Andes. Maximum crustal thicknesses of 70 74 km under the Western Cordillera and the Eastern Cordillera thin to 32 38 km 200 km east of the Andes in the Chaco Plain. The central Altiplano at 20°S has crustal thicknesses of 60 to 65 km. The crust also appears to thicken from north (16°S, 55 60 km) to south (20°S, 70 74 km) along the Eastern Cordillera. The Subandean zone crust has intermediate thicknesses of 43 to 47 km. Crustal-thickness predictions for the Andes based on Airy-type isostatic behavior show remarkable overall correlation with observed crustal thickness in the regions of high elevation. In contrast, at the boundary between the Eastern Cordillera and the Subandean zone and in the Chaco Plain, the crust is thinner than predicted, suggesting that the crust in these regions is supported in part by the flexural rigidity of a strong lithosphere. With additional constraints, we conclude that the observation of Airy-type isostasy is consistent with thickening associated with compressional shortening of a weak lithosphere squeezed between the stronger lithosphere of the subducting Nazca plate and the cratonic lithosphere of the Brazilian craton.

  9. Ultrasound settings significantly alter arterial lumen and wall thickness measurements

    OpenAIRE

    Green Daniel J; Reed Christopher J; Potter Kathleen; Hankey Graeme J; Arnolda Leonard F

    2008-01-01

    Abstract Background Flow-mediated dilation (FMD) and carotid intima-medial thickness (CIMT), measured by ultrasound, are widely used to test the efficacy of cardioprotective interventions. Although assessment methods vary, automated edge-detecting image analysis software is routinely used to measure changes in FMD and CIMT. We aimed to quantify the effect that commonly adjusted ultrasound settings have on arterial lumen and wall thickness measurements made with CIMT measurement software. Meth...

  10. Correlation between Peak Expiratory Flow and Abdominal Muscle Thickness

    OpenAIRE

    Ishida, Hiroshi; Kobara, Kenichi; Osaka, Hiroshi; Suehiro, Tadanobu; Ito, Tomotaka; Kurozumi, Chiharu; Watanabe, Susumu

    2014-01-01

    [Purpose] The purpose of this study was to determine whether forced expiration is correlated with abdominal muscle thickness. [Subjects] Twenty-three healthy male volunteers participated in this study. [Methods] The peak expiratory flow (PEF) was obtained using a peak flow meter with subjects in the sitting position. The thicknesses of the right rectus abdominis, external oblique, internal oblique, and transverse abdominis muscles were measured using B-mode ultrasonography at the end of a rel...

  11. Elemental Abundance Survey of The Galactic Thick Disk

    CERN Document Server

    Reddy, B E; Allende-Prieto, C; Reddy, Bacham E.; Lambert, David L.; Prieto, Carlos Allende

    2006-01-01

    [Abridged abstract] We have performed an abundance analysis for 176 F- and G- dwarfs of the Galactic thick disk component. Using accurate radial velocities combined with $Hipparcos$ astrometry, kinematics (U, V, and W) and Galactic orbital parameters were computed. We estimate the probability for a star to belong to the thin disk, the thick disk or the halo. Abundances of C, O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Ba, Ce, Nd, and Eu have been obtained. The abundances for thick disk stars are compared with those for thin disk members from Reddy et al. (2003). The ratios of $\\alpha$-elements (O, Mg, Si, Ca and Ti) to iron for thick disk disk stars show a clear enhancement compared to thin disk members in the range $-0.3 <$ [Fe/H] $ < -1.2$. There are also other elements -- Al, Sc, V, Co, and possibly Zn -- which show enhanced ratios to iron in the thick disk relative to the thin disk. The abundances of Na, Cr, Mn, Ni, and Cu (relative to Fe) are very similar for thin and thick dis...

  12. Thickness dependence of fracture behaviour in a superconducting strip

    International Nuclear Information System (INIS)

    When subjected to a magnetic field, a superconducting strip will undergo an electromagnetic body force induced by flux pinning. The magnitude of the body force is dependent on the critical current density. It is well known that the critical current density in the strip will decrease with increasing thickness. In addition, the mechanical behaviour of the strip will also be affected by the thickness of the strip. Thus, the strip thickness has an influence on both the electromagnetic and mechanical behaviours. In this paper, we analyse the fracture behaviour by considering the competition of electromagnetic and mechanical behaviours. In order to study the central crack problem of a superconducting strip with different thicknesses, we replace the electromagnetic body force with the total surface force. Using a Fourier transform method, the boundary value problem is reduced to a singular integral equation. By solving the singular integral equation, we obtain the stress intensity factors for two different crack lengths during field descent. The results show that the stress intensity factor is not a monotonic function of the thickness and that two competing factors dominate in different field regions. It is necessary to obtain the optimized thickness by considering both the superconductivity and mechanical behaviour in the superconducting strip. (paper)

  13. ICESat: Sea ice freeboard, snow depth, and thickness

    Science.gov (United States)

    Kwok, R.

    2007-12-01

    Total freeboard (snow and ice) and thickness of the Arctic Ocean sea ice cover are derived from ICESat data for two 35-day periods: one during the fall (Oct-Nov) of 2005 and the other during the winter (Feb-Mar) of 2006. Our freeboard retrieval approach is based on reflectivity and the expected statistics of freeboard variability from combined analysis of RADARSAT/ICESat data. Results suggest that our retrieval procedures could provide consistent freeboard estimates along 25-km segments with uncertainties of better than several centimeters. With a climatology of snow density, ECMWF snowfall is used to construct a time-varying field of snow depth for the conversion of freeboard to sea ice thickness. The derived ice thickness estimates are compared with ice draft observations from moored upward looking sonar data and the snow depth/thickness data from mass balance buoys in the Beaufort Sea. Preliminary results show that the estimated ICESat thickness estimates are within 0.5 m of the ice drafts reported by moorings. In this talk, we highlight some of the issues associated with the process of freeboard retrieval, thickness estimation, and quality assessment due to the disparity of spatial resolution between the ICESat footprint and those from in-situ measurements.

  14. NONLINEAR NATURAL FREQUENCY OF SHALLOW CONICAL SHELLS WITH VARIABLE THICKNESS

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-zhi; HAN Ming-jun; ZHAO Yong-gang; YEH Kai-yuan

    2005-01-01

    The nonlinear dynamical variation equation and compatible equation of the shallow conical shell with variable thickness are obtained by the theory of nonlinear dynamical variation equation and compatible equation of the circular thin plate with variable thickness. Assuming the thin film tension is composed of two items. The compatible equation is transformed into two independent equations. Selecting the maximum amplitude in the center of the shallow conical shells with variable thickness as the perturbation parameter,the variation equation and the differential equation are transformed into linear expression by theory of perturbation variation method. The nonlinear natural frequency of shallow conical shells with circular bottom and variable thickness under the fixed boundary conditions is solved. In the first approximate equation, the linear natural frequency of shallow conical shells with variable thickness is obtained. In the third approximate equation, the nonlinear uatural frequency of it is obtained. The figures of the characteristic curves of the natural frequency varying with stationary loads, large amplitude, and variable thickness coefficient are plotted. A valuable reference is given for dynamic engineering.

  15. Bark thickness across the angiosperms: more than just fire.

    Science.gov (United States)

    Rosell, Julieta A

    2016-07-01

    Global variation in total bark thickness (TBT) is traditionally attributed to fire. However, bark is multifunctional, as reflected by its inner living and outer dead regions, meaning that, in addition to fire protection, other factors probably contribute to TBT variation. To address how fire, climate, and plant size contribute to variation in TBT, inner bark thickness (IBT) and outer bark thickness (OBT), I sampled 640 species spanning all major angiosperm clades and 18 sites with contrasting precipitation, temperature, and fire regime. Stem size was by far the main driver of variation in thickness, with environment being less important. IBT was closely correlated with stem diameter, probably for metabolic reasons, and, controlling for size, was thicker in drier and hotter environments, even fire-free ones, probably reflecting its water and photosynthate storage role. OBT was less closely correlated with size, and was thicker in drier, seasonal sites experiencing frequent fires. IBT and OBT covaried loosely and both contributed to overall TBT variation. Thickness variation was higher within than across sites and was evolutionarily labile. Given high within-site diversity and the multiple selective factors acting on TBT, continued study of the different drivers of variation in bark thickness is crucial to understand bark ecology. PMID:26890029

  16. Parametric Investigation of Optimum Thermal Insulation Thickness for External Walls

    Directory of Open Access Journals (Sweden)

    Omer Kaynakli

    2011-06-01

    Full Text Available Numerous studies have estimated the optimum thickness of thermal insulation materials used in building walls for different climate conditions. The economic parameters (inflation rate, discount rate, lifetime and energy costs, the heating/cooling loads of the building, the wall structure and the properties of the insulation material all affect the optimum insulation thickness. This study focused on the investigation of these parameters that affect the optimum thermal insulation thickness for building walls. To determine the optimum thickness and payback period, an economic model based on life-cycle cost analysis was used. As a result, the optimum thermal insulation thickness increased with increasing the heating and cooling energy requirements, the lifetime of the building, the inflation rate, energy costs and thermal conductivity of insulation. However, the thickness decreased with increasing the discount rate, the insulation material cost, the total wall resistance, the coefficient of performance (COP of the cooling system and the solar radiation incident on a wall. In addition, the effects of these parameters on the total life-cycle cost, payback periods and energy savings were also investigated.

  17. Thin film thickness measurements using Scanning White Light Interferometry

    International Nuclear Information System (INIS)

    Scanning White Light Interferometry is a well-established technique for providing accurate surface roughness measurements and three dimensional topographical images. Here we report on the use of a variant of Scanning White Light Interferometry called coherence correlation interferometry which is now capable of providing accurate thickness measurements from transparent and semi-transparent thin films with thickness below 1 μm. This capability will have many important applications which include measurements on optical coatings, displays, semiconductor devices, transparent conducting oxides and thin film photovoltaics. In this paper we report measurements of thin film thickness made using coherence correlation interferometry on a variety of materials including metal-oxides (Nb2O5 and ZrO2), a metal-nitride (SiNx:H), a carbon-nitride (SiCxNy:H) and indium tin oxide, a transparent conducting oxide. The measurements are compared with those obtained using spectroscopic ellipsometry and in all cases excellent correlation is obtained between the techniques. A key advantage of this capability is the combination of thin film thickness and surface roughness and other three-dimensional metrology measurements from the same sample area. - Highlights: • Capability to make thin film measurements with sub-nanometre accuracy • Measurements of thin film thickness made on metal-oxides, nitrides and carbon-nitrides • Excellent correlation with thickness measurements using spectroscopic ellipsometry • Thin film measurement and nanometrology from the same sample area

  18. Stress measurement in thick plates using nonlinear ultrasonics

    International Nuclear Information System (INIS)

    In this paper the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded thick steel plates using fundamental theory of nonlinear ultrasonics is investigated in order to measure the stress state at a given cross section. The measurement concept is based on phased array placement of ultrasonic transmitter-receiver to scan three angles of a given cross section using Rayleigh waves. The change in the ultrasonic data in thick steel plates is influenced by normal and shear stresses; therefore, three measurements are needed to solve the equations simultaneously. Different thickness plates are studied in order to understand the interaction of Rayleigh wave penetration depth and shear stress. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The influences of plate thickness and ultrasonic frequency on the identification of stress tensor are numerically studied in 3D structural geometry and Murnaghan material model. The experimental component of this study includes uniaxial loading of the plate while measuring ultrasonic wave at three directions (perpendicular, parallel and angled to the loading direction). Instead of rotating transmitter-receiver pair for each test, a device capable of measuring the three angles is designed

  19. Estimation of sand dune thickness using a vertical velocity profile

    International Nuclear Information System (INIS)

    Previous field and mathematical studies have shown that sand dunes may have vertical velocity profiles (i.e. continuous increase of velocity with depth). Therefore, computing the dunes thickness using conventional seismic refraction methods that assume a vertically homogeneous layer will likely produce some errors. The purpose of this study is to quantify the effect of the vertical velocity profile in a sand dune on the process of thickness estimation using seismic refraction data. First, the time distance (T-X) data of the direct wave in the dune is calculated using a vertical velocity profile, V (z), derived from Hertz-Mindlin contact theory. Then the thickness is estimated from the calculated T-X data, intercept time and velocity of the refractor at the dune's base assuming a constant velocity in the dune. The error in the estimated thickness due to the constant-velocity assumption increases with increasing thickness and decreasing porosity of the dune. For sand dunes with porosities greater than 0.2 and thickness less than 200 meter, the error is less than 15%. (author)

  20. Thin film thickness measurements using Scanning White Light Interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Maniscalco, B.; Kaminski, P.M.; Walls, J.M., E-mail: J.M.Walls@lboro.ac.uk

    2014-01-01

    Scanning White Light Interferometry is a well-established technique for providing accurate surface roughness measurements and three dimensional topographical images. Here we report on the use of a variant of Scanning White Light Interferometry called coherence correlation interferometry which is now capable of providing accurate thickness measurements from transparent and semi-transparent thin films with thickness below 1 μm. This capability will have many important applications which include measurements on optical coatings, displays, semiconductor devices, transparent conducting oxides and thin film photovoltaics. In this paper we report measurements of thin film thickness made using coherence correlation interferometry on a variety of materials including metal-oxides (Nb{sub 2}O{sub 5} and ZrO{sub 2}), a metal-nitride (SiN{sub x}:H), a carbon-nitride (SiC{sub x}N{sub y}:H) and indium tin oxide, a transparent conducting oxide. The measurements are compared with those obtained using spectroscopic ellipsometry and in all cases excellent correlation is obtained between the techniques. A key advantage of this capability is the combination of thin film thickness and surface roughness and other three-dimensional metrology measurements from the same sample area. - Highlights: • Capability to make thin film measurements with sub-nanometre accuracy • Measurements of thin film thickness made on metal-oxides, nitrides and carbon-nitrides • Excellent correlation with thickness measurements using spectroscopic ellipsometry • Thin film measurement and nanometrology from the same sample area.