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Sample records for sub-50 nm particles

  1. Flat super-oscillatory lens for heat-assisted magnetic recording with sub-50 nm resolution.

    Science.gov (United States)

    Yuan, Guanghui; Rogers, Edward T F; Roy, Tapashree; Shen, Zexiang; Zheludev, Nikolay I

    2014-03-24

    Heat-assisted magnetic recording (HAMR) is a future roadmap technology to overcome the superparamagnetic limit in high density magnetic recording. Existing HAMR schemes depend on a simultaneous magnetic stimulation and light-induced local heating of the information carrier. To achieve high-density recorded data, near-field plasmonic transducers have been proposed as light concentrators. Here we suggest and investigate in detail an alternative approach exploiting a far-field focusing device that can focus light into sub-50 nm hot-spots in the magnetic recording layer using a laser source operating at 473 nm. It is based on a recently introduced super-oscillatory flat lens improved with the use of solid immersion, giving an effective numerical aperture as high as 4.17. The proposed solution is robust and easy to integrate with the magnetic recording head thus offering a competitive advantage over plasmonic technology.

  2. Study on the oxidation and reduction of tungsten surface for sub-50 nm patterning process

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Kyu; Nam, Seok Woo; Cho, Sung Il; Jhon, Myung S.; Min, Kyung Suk; Kim, Chan Kyu; Jung, Ho Bum; Yeom, Geun Young [Memory Division Semiconductor Business, Samsung Electronics, San No. 16 Banwol-Ri, Taean-Eup, Hwasung-City, Gyeonggi-Do 449-711, South Korea and Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of); Memory Division Semiconductor Business, Samsung Electronics, San No. 16 Banwol-Ri, Taean-Eup, Hwasung-City, Gyeonggi-Do 449-711 (Korea, Republic of); Department of Chemical Engineering and Data Storage Systems Center, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

    2012-11-15

    The oxidation characteristics of tungsten line pattern during the carbon-based mask-layer removal process using oxygen plasmas have been investigated for sub-50 nm patterning processes, in addition to the reduction characteristics of the WO{sub x} layer formed on the tungsten line surface using hydrogen plasmas. The surface oxidation of tungsten lines during the mask layer removal process could be minimized by using low-temperature (300 K) plasma processing for the removal of the carbon-based material. Using this technique, the thickness of WO{sub x} on the tungsten line could be decreased to 25% compared to results from high-temperature processing. The WO{sub x} layer could also be completely removed at a low temperature of 300 K using a hydrogen plasma by supplying bias power to the tungsten substrate to provide a activation energy for the reduction. When this oxidation and reduction technique was applied to actual 40-nm-CD device processing, the complete removal of WO{sub x} formed on the sidewall of tungsten line could be observed.

  3. Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao [National Synchrotron Radiation Laboratory (China); Liu Yijin [School of Physics (China); Yue Zhengbo; Yu Hanqing [Laboratory of Environmental Engineering, School of Chemistry, University of Science and Technology of China, Hefei Anhui 230029 (China); Wang Chunru, E-mail: ychtian@ustc.edu.c [Institute of Chemistry, Chinese Academy of Sciences, Beijing 10060 (China)

    2009-09-01

    A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 {mu}m thickness and 4 {mu}m width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

  4. Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

    International Nuclear Information System (INIS)

    Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao; Liu Yijin; Yue Zhengbo; Yu Hanqing; Wang Chunru

    2009-01-01

    A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 μm thickness and 4 μm width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

  5. Sub-50 nm patterning of functional oxides by soft lithographic edge printing

    NARCIS (Netherlands)

    George, A.; ten Elshof, Johan E.

    2012-01-01

    We report a fast, versatile and reproducible method to make arbitrary nanoscale patterns of functional metal oxides by edge transfer printing of aqueous metal-loaded water-soluble polyacrylic acid (PAA) solutions on silicon. Patterns of ZnO, CuO, NiO and Fe2O3 with lateral dimensions below 50 nm

  6. Sub-50-nm self-assembled nanotextures for enhanced broadband antireflection in silicon solar cells.

    Science.gov (United States)

    Rahman, Atikur; Ashraf, Ahsan; Xin, Huolin; Tong, Xiao; Sutter, Peter; Eisaman, Matthew D; Black, Charles T

    2015-01-21

    Materials providing broadband light antireflection have applications as highly transparent window coatings, military camouflage, and coatings for efficiently coupling light into solar cells and out of light-emitting diodes. In this work, densely packed silicon nanotextures with feature sizes smaller than 50 nm enhance the broadband antireflection compared with that predicted by their geometry alone. A significant fraction of the nanotexture volume comprises a surface layer whose optical properties differ substantially from those of the bulk, providing the key to improved performance. The nanotexture reflectivity is quantitatively well-modelled after accounting for both its profile and changes in refractive index at the surface. We employ block copolymer self-assembly for precise and tunable nanotexture design in the range of ~10-70 nm across macroscopic solar cell areas. Implementing this efficient antireflection approach in crystalline silicon solar cells significantly betters the performance gain compared with an optimized, planar antireflection coating.

  7. Sub-50 nm gate length SOI transistor development for high performance microprocessors

    International Nuclear Information System (INIS)

    Horstmann, M.; Greenlaw, D.; Feudel, Th.; Wei, A.; Frohberg, K.; Burbach, G.; Gerhardt, M.; Lenski, M.; Stephan, R.; Wieczorek, K.; Schaller, M.; Hohage, J.; Ruelke, H.; Klais, J.; Huebler, P.; Luning, S.; Bentum, R. van; Grasshoff, G.; Schwan, C.; Cheek, J.; Buller, J.; Krishnan, S.; Raab, M.; Kepler, N.

    2004-01-01

    Partial depleted (PD) SOI technologies have reached maturity for production of high speed, low power microprocessors. The paper will highlight several challenges found during the course of development for bringing 40 nm gate length (L GATE ) PD SOI transistors into volume manufacturing for high-speed microprocessors. The key innovations developed for this transistor in order to overcome classical gate oxide and L GATE scaling is an unique differential triple spacer structure, stressed overlayer films inducing strain in the Silicon channel and optimized junctions. This transistor structure yields an outstanding ring oscillator speed with an unloaded inverter delay of 5.5 ps. The found improvements are highly manufacturable and scaleable for future device technologies like FD SOI

  8. Sub-50 nm metrology on extreme ultra violet chemically amplified resist—A systematic assessment

    International Nuclear Information System (INIS)

    Maas, D. J.; Herfst, R.; Veldhoven, E. van; Fliervoet, T.; Meessen, J.; Vaenkatesan, V.; Sadeghian, H.

    2015-01-01

    With lithographic patterning dimensions decreasing well below 50 nm, it is of high importance to understand metrology at such small scales. This paper presents results obtained from dense arrays of contact holes (CHs) with various Critical Dimension (CD) between 15 and 50 nm, as patterned in a chemically amplified resist using an ASML EUV scanner and measured at ASML and TNO. To determine the differences between various (local) CD metrology techniques, we conducted an experiment using optical scatterometry, CD-Scanning Electron Microscopy (CD-SEM), Helium ion Microscopy (HIM), and Atomic Force Microscopy (AFM). CD-SEM requires advanced beam scan strategies to mitigate sample charging; the other tools did not need that. We discuss the observed main similarities and differences between the various techniques. To this end, we assessed the spatial frequency content in the raw images for SEM, HIM, and AFM. HIM and AFM resolve the highest spatial frequencies, which are attributed to the more localized probe-sample interaction for these techniques. Furthermore, the SEM, HIM, and AFM waveforms are analyzed in detail. All techniques show good mutual correlation, albeit the reported CD values systematically differ significantly. HIM systematically reports a 25% higher CD uniformity number than CD-SEM for the same arrays of CHs, probably because HIM has a higher resolution than the CD-SEM used in this assessment. A significant speed boost for HIM and AFM is required before these techniques are to serve the demanding industrial metrology applications like optical critical dimension and CD-SEM do nowadays

  9. Achieving sub-50nm controlled diameter of aperiodic Si nanowire arrays by ultrasonic catalyst removal for photonic applications

    Science.gov (United States)

    Chaliyawala, Harsh A.; Purohit, Zeel; Khanna, Sakshum; Ray, Abhijit; Pati, Ranjan K.; Mukhopadhyay, Indrajit

    2018-05-01

    We report an alternative approach to fabricate the vertically aligned aperiodic Si nanowire arrays by controlling the diameter of the Ag nanoparticles and tuneable ultrasonic removal. The process begins by sputtering the Ag thin film (t=5 nm) on the Si/SiO2 substrates. Followed by Ag thin film, annealed for various temperature (T=300°C, 400°C, 500°C and 600°C) to selectively achieve a high density, well-spaced and diameter controlled Ag nanoparticles (AgNPs) on the Si/SiO2 substrates. The sacrificial layer of AgNPs size indicates the controlled diameter of the Si nanowire arrays. Image J analysis for various annealed samples gives an indication of the high density, uniformity and equal distribution of closely packed AgNPs. Furthermore, the AgNPs covered with Au/Pd mesh (5 nm) as a template, was removed by ultrasonication in the etchant solution for several times in different intervals of preparation. The conventional and facile metal assisted electroless etching approach was finally employed to fabricate the vertically aperiodic sub-50 nm SiNWAs, can be applicable to various nanoscale opto-electronic applications.

  10. Plasmonic nanoparticle lithography: Fast resist-free laser technique for large-scale sub-50 nm hole array fabrication

    Science.gov (United States)

    Pan, Zhenying; Yu, Ye Feng; Valuckas, Vytautas; Yap, Sherry L. K.; Vienne, Guillaume G.; Kuznetsov, Arseniy I.

    2018-05-01

    Cheap large-scale fabrication of ordered nanostructures is important for multiple applications in photonics and biomedicine including optical filters, solar cells, plasmonic biosensors, and DNA sequencing. Existing methods are either expensive or have strict limitations on the feature size and fabrication complexity. Here, we present a laser-based technique, plasmonic nanoparticle lithography, which is capable of rapid fabrication of large-scale arrays of sub-50 nm holes on various substrates. It is based on near-field enhancement and melting induced under ordered arrays of plasmonic nanoparticles, which are brought into contact or in close proximity to a desired material and acting as optical near-field lenses. The nanoparticles are arranged in ordered patterns on a flexible substrate and can be attached and removed from the patterned sample surface. At optimized laser fluence, the nanohole patterning process does not create any observable changes to the nanoparticles and they have been applied multiple times as reusable near-field masks. This resist-free nanolithography technique provides a simple and cheap solution for large-scale nanofabrication.

  11. AFM visualization of sub-50nm polyplex disposition to the nuclear pore complex without compromising the integrity of the nuclear envelope

    DEFF Research Database (Denmark)

    Andersen, Helene; Parhamifar, Ladan; Hunter, A Christy

    2016-01-01

    that were microinjected into the oocytes of Xenopus laevis, as an example of a non-dividing cell, is exclusive to the nuclear pore complex (NPC). AFM images show NPCs clogged only with sub-50nm polyplexes. This mode of disposition neither altered the morphology/integrity of the nuclear membrane nor the NPC...

  12. Preparation and Loading with Rifampicin of Sub-50nm Poly(ethyl cyanoacrylate Nanoparticles by Semicontinuous Heterophase Polymerization

    Directory of Open Access Journals (Sweden)

    H. Saade

    2016-01-01

    Full Text Available We report the preparation of poly(ethyl cyanoacrylate (PECA nanoparticles by semicontinuous heterophase polymerization carried out at monomer starved conditions at three monomer addition rates. Particles in the nanometer range were obtained, the size of which diminishes with decreasing monomer addition rate as shown by the fact that particles with mean diameters of ca. 42 and 30 nm were obtained at the faster and intermediate dosing rates, respectively, whereas two populations of particles, one of 15.5 and the other of 36 nm in mean diameters, were produced at the slower dosing rate. The obtained molecular weights were from 2,200 to 3,500 g/mol, depending on the addition rate, which are typical of the anionic polymerizations of cyanoacrylates in aqueous dispersions at low pHs. The rifampicin (RIF loading into the nanoparticles was successful since the entire drug added was incorporated. The drug release study carried out at pH of 7.2 indicated a faster release from the free RIF at intermediate and larger release times as expected since, in the nanoparticles, first the drug has to diffuse through the nanoparticle structure. The comparison of several drug release models indicates that the RIF release from PECA nanoparticles follows that of Higuchi.

  13. Resolving three-dimensional shape of sub-50nm wide lines with nanometer-scale sensitivity using conventional optical microscopes

    International Nuclear Information System (INIS)

    Attota, Ravikiran; Dixson, Ronald G.

    2014-01-01

    We experimentally demonstrate that the three-dimensional (3-D) shape variations of nanometer-scale objects can be resolved and measured with sub-nanometer scale sensitivity using conventional optical microscopes by analyzing 4-D optical data using the through-focus scanning optical microscopy (TSOM) method. These initial results show that TSOM-determined cross-sectional (3-D) shape differences of 30 nm–40 nm wide lines agree well with critical-dimension atomic force microscope measurements. The TSOM method showed a linewidth uncertainty of 1.22 nm (k = 2). Complex optical simulations are not needed for analysis using the TSOM method, making the process simple, economical, fast, and ideally suited for high volume nanomanufacturing process monitoring.

  14. Optical properties change in Te diffused As{sub 50}Se{sub 50} chalcogenide thin film

    Energy Technology Data Exchange (ETDEWEB)

    Naik, Ramakanta; Behera, M.; Panda, R.; Mishra, N. C. [Department of Physics, Utkal University, Bhubaneswar, 751004, Odisha (India)

    2016-05-23

    In the present report, we present the effect of Te diffusion into As{sub 50}Se{sub 50} thin film which changes the optical properties. The Te/As{sub 50}Se{sub 50} film was irradiated by a laser beam of 532 nm to study the diffusion mechanism due to photo induced effect. The As{sub 50}Se{sub 50}, Te/As{sub 50}Se{sub 50} films show a completely amorphous nature from X-ray diffraction study. A non direct transition was found for these films on the basis of optical transmission data carried out by Fourier Transform infrared Spectroscopy. The optical bandgap is found to be decreased with Te deposition and photo darkening phenomena is observed for the diffused film. The change in the optical constants are well supported by the corresponding change in different types of bonds which are being studied by X-ray photoelectron spectroscopy.

  15. Dust Explosion Characteristics of Agglomerated 35 nm and 100 nm Aluminum Particles

    Directory of Open Access Journals (Sweden)

    Hong-Chun Wu

    2010-01-01

    Full Text Available In the experiment, nanoparticles of 35 nm Al and 100 nm Al powders, respectively, formed particles with average sizes of 161 nm and 167 nm in agglomeration. The characteristics of dust cloud explosions with the two powder sizes, 35 nm and 100 nm, revealed considerable differences, as shown here: (dp/dtmax-35 nm = 1254 bar/s, (dp/dtmax-100 nm = 1105 bar/s; Pmax-35 nm = 7.5 bar, Pmax-100 nm = 12.3 bar, and MEC-35 nm = 40 g/m3, MEC-100 nm = 50 g/m3. The reason of Pmax-35 nm value is smaller than Pmax-100 nm may be due to agglomeration. From an analysis of the explosive residue, the study found that nanoparticles of 35 nm Al powder became filamentous strands after an explosion, where most of 100 nm Al nanoparticles maintained a spherical structure, This may be because the initial melting temperature of 35 nm Al is 435.71°C, while that for 100 nm Al is 523.58°C, higher by 87.87°C. This study discovered that explosive property between the 35 nm Al and 100 nm Al powders after agglomeration were different.

  16. Laser ablation of nanoscale particles with 193 nm light

    International Nuclear Information System (INIS)

    Choi, J H; Lucas, D; Koshland, C P

    2007-01-01

    Laser interaction with nanoscale particles is distinct and different from laser-bulk material interaction, where a hot plasma is normally created. Here, we review our studies on 193 nm laser ablation of various nanoscale particles including NaCl, soot, polystyrene, and gold. The 20 ns laser beam with fluences up to 0.3 J/cm 2 irradiates nanoparticles in a gas stream at laser repetition rates from 10 to 100 Hz. The particle size distributions before and after irradiation are measured with a scanning mobility particle sizer (SMPS), and particle morphology is examined with electron microscopy. All the nanomaterials studied exhibit a similar disintegration pattern and similar particle formation characteristics. No broadband emission associated with particle heating or optical breakdown is observed. The nanoparticles formed after irradiation have a smaller mean diameter and an order of magnitude higher number concentration with a more spherical shape compared to the original particles. We use the photon-atom ratio (PAR) to interpret the laser-particle interaction energetics

  17. Magnetic hardening of Fe{sub 50}Co{sub 50} by rotary swaging

    Energy Technology Data Exchange (ETDEWEB)

    Gröb, T., E-mail: t.groeb@phm.tu-darmstadt.de [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Wießner, L. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Bruder, E. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Faske, T.; Donner, W. [Divison Structure Research, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Groche, P. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Müller, C. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany)

    2017-04-15

    Fe{sub 50}Co{sub 50} was subjected to incremental forming by rotary swaging with the aim of tailoring the coercivity by changing the microstructure. The challenging part of a deformation of Fe{sub 50}Co{sub 50} is an ordering phase present at room temperature, leading to low formability. To increase the formability of the alloy the presence of the ordering phase was supressed by two different concepts. The first concept consists of a heat treatment above the phase transition followed by rapid cooling and deformation at room temperature. The second concept was rotary swaging at temperatures above the phase transition temperature. A comparison in terms of resulting microstructure and magnetic properties shows that both concepts have a potential for tailoring the coercivity of Fe{sub 50}Co{sub 50}. - Highlights: • Magnetic hardening of Fe{sub 50}Co{sub 50} was achieved by rotary swaging with two different concepts. • The influences of the microstructural changes during the rotary swaging process have been linked to magnetic hardening. • Increase in coercivity for Fe{sub 50}Co{sub 50} by rotary swaging at elevated temperature is limited by the dynamic restoration. • Coercivity of Fe{sub 50}Co{sub 50} can be tailored by the induced plastic strain.

  18. Magnetic spin configuration in Fe{sub 50}Pt{sub 50-x}Rh{sub x} alloys

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, J.; Lott, D.; Schreyer, A. [GKSS Research Centre (Germany); Mankey, G.J. [University of Alabama, MINT Center (United States); Schmidt, W.; Schmalzl, K. [Juelich Research Centre (Germany); Tartakowskaya, E. [Institute for Magnetism, National Ukrainian Accademy of Science (Ukraine)

    2010-07-01

    FePt-based alloys are typically the material of choice for magnetic information storage media. The high magnetic moment of Fe gives a large magnetization and the large atomic number of Pt results in a high magnetic anisotropy. This combination enables the written bits to be smaller than ever before. One way to control the magnetic properties in these materials is through the introduction of a third element into the crystal matrix e.g. Rh. When Rh is added to replace Pt in the equiatomic alloy, new magnetic phases emerge. Bulk samples of Fe{sub 50}Pt{sub 50-x}Rh{sub x} studied by magnetization measurements refer to three different phase transitions with increasing temperature: (I) An antiferromagnetic (AF)-paramagnetic (PM) transition for 30nm Fe{sub 50}Pt{sub 50-x}Rh{sub x} films with different Rh concentrations. These films were examined by neutron diffraction in dependence of temperature and magnetic field. By the use of polarized and unpolarized neutron diffraction we could develop a detailed model of the magnetic spin structure in these thin films.

  19. Ferromagnetic resonance study of Fe{sub 50}Ag{sub 50} granular film

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento, G. [Dpto. Electricicidad y Electronica, Universidad del Pais Vasco (UPV/EHU), Apdo. 644, 48080 Bilbao (Spain)]. E-mail: websamug@lg.ehu.es; Fdez-Gubieda, M.L. [Dpto. Electricicidad y Electronica, Universidad del Pais Vasco (UPV/EHU), Apdo. 644, 48080 Bilbao (Spain); Siruguri, V. [Dpto. Electricicidad y Electronica, Universidad del Pais Vasco (UPV/EHU), Apdo. 644, 48080 Bilbao (Spain); UGC-DAE Consortium for Scientific Research, R-5 Shed, BARC Campus, Mumbai 400085 (India); Lezama, L. [Dpto. Quimica Inorganica (UPV/EHU), Apdo. 644, 48080, Bilbao (Spain); Orue, I. [Servicios Generales de Investigacion (SGIKER), Vicerrectorado de Investigacion (UPV/EHU) (Spain)

    2007-09-15

    Fe{sub 50}Ag{sub 50} granular film, produced by the pulsed laser deposition technique, has been studied using ferromagnetic resonance (FMR) at temperatures ranging from 4 to 300K. Three different resonance modes are well observed in the whole temperature range. We have also studied the angular evolution of the resonance peaks at three different temperatures T=150, 250, 300K. The thermal and the angular evolution of the three resonance fields has been interpreted on the basis of the existence of different magnetic coupling between the Fe nanoparticles and a weakly magnetized interface.

  20. Magnetic properties and configuration of Fe{sub 50}Pt{sub 50*x}Rh{sub x} films

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, Jochen; Lott, Dieter; Schreyer, Andreas [Helmholt-Zentrum, Geesthacht (Germany); Schmidt, Wolfgang; Schmalzl, Karin [IFF Forschungszentrum, Juelich (Germany); JCNS at ILL (France); Mankey, Gary J. [MINT Center, University of Alabama (United States); Klose, Frank [Ansto, Bragg Institute (Australia); Tartakowskaya, Helena [Institute for Magnetism, National Accademy of Scinece (Ukraine)

    2011-07-01

    Ordered FePt alloys with L1{sub 0} structure are known as materials with FM order and a high magnetic moment of Fe providing a large magnetization. The large atomic number of Pt on the other hand results in a high magnetic anisotropy. If grown in thin films, the high anisotropy often results in perpendicular magnetization which is the preferred orientation for current magnetic recording media. One way to control the magnetic properties in these materials is through the introduction of a third element into the crystal matrix e.g. Rh. When Rh is added to replace Pt in the equiatomic alloy, new magnetic phases emerge. Here we present neutron diffraction studies on the magnetic properties of different 200nm thick Fe{sub 50}Pt{sub 50*x}Rh{sub x} films in dependence of the temperature and external magnetic fields. Additional resonant x-ray measurements on the Fe and Pt absorption edges provide additional information about the magnetic moments on these sites.

  1. Sub 20nm particle inspection on EUV mask blanks

    NARCIS (Netherlands)

    Bussink, P.G.W.; Volatier, J.B.; Walle, P. van der; Fritz, E.C.; Donck, J.C.J. van der

    2016-01-01

    The Rapid Nano is a particle inspection system developed by TNO for the qualification of EUV reticle handling equipment. The detection principle of this system is dark-field microscopy. The performance of the system has been improved via model-based design. Through our model of the scattering

  2. Size-resolved fluxes of sub-100-nm particles over forests

    DEFF Research Database (Denmark)

    Pryor, Sara; Barthelmie, Rebecca Jane; Spaulding, A.M.

    2009-01-01

    Dry deposition of atmospheric particles is critically dependent on particle size and plays a key role in dictating the mass and number distributions of atmospheric particles. However, modeling dry deposition is constrained by a lack of understanding of controlling dependencies and accurate size......-resolved observations. We present size-resolved particle number fluxes for sub-100-nm particle diameters (Dp) over a deciduous forest derived using eddy covariance applied to data from a fast mobility particle sizer. The size-resolved particle number fluxes in 18 diameters between 8 and 100 nm were collected during...... leaf-on and are statistically robust. Particle deposition velocities normalized by friction velocity (v d +) are approximately four times smaller than comparable values for coniferous forests reported elsewhere. Comparison of the data with output from a new one-dimensional mechanistic particle...

  3. Magnetic rotational hysteresis study on spherical 85-160 nm Fe3O4 particles

    Science.gov (United States)

    Schmidbauer, E.

    1988-05-01

    Rotational hysteresis losses Wr were determined as a function of magnetic field H for dispensed spherical Fe3O4 particles of mean grain sizes 85 nm, 127 nm and 162 nm between 78 K and 294 K. The observed Wr-H curves are compared with theoretical curves for single domain particles. The analysed particles reveal centers of high magnetic anisotropy. Such centers can be of importance during the generation of a thermoremanent magnetization, as they may be the origin of enhanced magnetic stability.

  4. Perpendicular magnetic anisotropy of non-epitaxial hexagonal Co{sub 50}Pt{sub 50} thin films prepared at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, F.T., E-mail: ftyuan@gmail.com [iSentek Ltd., Advanced Sensor Laboratory, New Taipei City 22101, Taiwan (China); Chang, H.W., E-mail: wei0208@gmail.com [Department of Applied Physics, Tunghai University, Taichung 40704, Taiwan (China); Lee, P.Y.; Chang, C.Y. [Department of Applied Physics, Tunghai University, Taichung 40704, Taiwan (China); Chi, C.C. [Department of Materials Sciences and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Ouyang, H., E-mail: houyang@mx.nthu.edu.tw [Department of Materials Sciences and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2015-04-15

    Highlights: • In this paper, we propose a non-epitaxially grown PMA thin film of disorder hexagonal Co{sub 50}Pt{sub 50} which can satisfy all the requirements at once. • Although the preparation temperature is at room temperature and no post annealing is required, the film also shows good thermal stability up to 400 °C. • Moreover, the easy-controlling single layer deposition process of the film largely enhances the feasibility of practical production. • Significant PMA is achieved in a wide range of film thickness from 2 nm to 20 nm, which expands the usage form a GMR or TMR magnetic junctions to perpendicular spin polarizer for spin current related engineering. • The presented results may open new opportunities for advanced spintronic devices. - Abstract: Non-epitaxially induced perpendicular magnetic anisotropy (PMA) of Co{sub 50}Pt{sub 50} thin films at room temperature (RT) is reported. The CoPt film having a disordered hcp structure shows a magnetocrystalline anisotropy (K{sub u}{sup RT}) of 1–2 × 10{sup 6} erg/cm{sup 3} in a wide range of layer thickness from 2 to 20 nm. K{sub u}{sup RT} of about 1 × 10{sup 6} erg/cm{sup 3} can be preserved after a 400 °C-thermal cycle in the 5-nm-thick sample. Moderate PMA, large thickness range, simple preparation process, low formation temperature but good thermal stability make presented hcp CoPt become a remarkable option for advanced spintronic devices.

  5. Performance of diethylene glycol-based particle counters in the sub-3 nm size range

    CERN Document Server

    Wimmer, D; Franchin, A; Kangasluoma, J; Kreissl, F; Kürten, A; Kupc, A; Metzger, A; Mikkilä, J; Petäjä, J; Riccobono, F; Vanhanen, J; Kulmala, M; Curtius, J

    2013-01-01

    When studying new particle formation, the uncertainty in determining the "true" nucleation rate is considerably reduced when using condensation particle counters (CPCs) capable of measuring concentrations of aerosol particles at sizes close to or even at the critical cluster size (1–2 nm). Recently, CPCs able to reliably detect particles below 2 nm in size and even close to 1 nm became available. Using these instruments, the corrections needed for calculating nucleation rates are substantially reduced compared to scaling the observed formation rate to the nucleation rate at the critical cluster size. However, this improved instrumentation requires a careful characterization of their cut-off size and the shape of the detection efficiency curve because relatively small shifts in the cut-off size can translate into larger relative errors when measuring particles close to the cut-off size. Here we describe the development of two continuous-flow CPCs using diethylene glycol (DEG) as the working fluid. The desig...

  6. The role of the interface on the magnetic behaviour of granular Fe{sub 50}Ag{sub 50} film

    Energy Technology Data Exchange (ETDEWEB)

    Fdez-Gubieda, M.L. [Dpto. Electricidad y Electronica. Universidad del Pais Vasco Apdo 644. 48080 Bilbao (Spain)]. E-mail: malu@we.lc.ehu.es; Sarmiento, G. [Dpto. Electricidad y Electronica. Universidad del Pais Vasco Apdo 644. 48080 Bilbao (Spain); Fernandez Barquin, L. [CITIMAC, Universidad de Cantabria, Avda. de los Castros s/n, 39005 Santander (Spain); Orue, I. [SGIKER, Servicios Generales de medidas magneticas, Universidad del Pais Vasco (Spain)

    2007-03-15

    The magnetic behaviour of a Fe{sub 50}Ag{sub 50} granular thin film has been studied by means of AC and DC magnetic measurements. Exchange coupling between magnetic nanoparticles appears at T=<200K decreasing the coercive field of the sample. Additionally, an exchange bias is observed at low temperature related to the existence of a spin disordered interface around the nanoparticles.

  7. RapidNano: towards 20nm Particle Detection on EUV Mask Blanks

    NARCIS (Netherlands)

    Donck, J.C.J. van der; Bussink, P.G.W.; Fritz, E.C.; Walle, P. van der

    2016-01-01

    Cleanliness is a prerequisite for obtaining economically feasible yield levels in the semiconductor industry. For the next generation of lithographic equipment, EUV lithography, the size of yield-loss inducing particles for the masks will be smaller than 20 nm. Consequently, equipment for handling

  8. Influence of atomic ordering on sigma phase precipitation of the Fe{sub 50}Cr{sub 50} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Vélez, G.Y., E-mail: g.y.velezcastillo@gmail.com [Universidad del Valle, Departamento de Física, A.A. 25360 Cali (Colombia); Instituto de Física, Universidad Autónoma de San Luis Potosí, avenida Manuel Nava 6, zona universitaria, 78290 San Luis Potosí, SLP México (Mexico); Pérez Alcázar, G.A. [Universidad del Valle, Departamento de Física, A.A. 25360 Cali (Colombia)

    2015-09-25

    Highlights: • σ-FeCr phase can be delayed when α-FeCr phase is ordered. • The formation of σ phase is favored by concentration gradients of α phase. • We determine the iron occupation number of the five sites of σ-Fe{sub 50}Cr{sub 50}. - Abstract: In this work we report a study of the kinetic of the formation of the σ-Fe{sub 50}Cr{sub 50} alloy which is obtained by heat treatment of α-FeCr samples with different atomic ordering. Two α-FeCr alloys were obtained, one by mechanical alloying and the other by arc-melting. Both alloys were heated at 925 K for 170 h and then quenched into ice water. Before heat treatment both alloys exhibit α-FeCr disordered structure with greater ferromagnetic behavior in the alloy obtained by mechanical alloying due to its higher atomic disorder. The sigma phase precipitation is influenced by the atomic ordering of the bcc samples: in the alloy obtained by mechanical alloying, the bcc phase is completely transformed into the σ phase; in the alloy obtained by melted the α–σ transformation is partial.

  9. Radon decay products and 10–1100 nm aerosol particles in Postojna Cave

    Directory of Open Access Journals (Sweden)

    M. Bezek

    2013-03-01

    Full Text Available At the lowest point along the tourist route in Postojna Cave, the activity concentration of radon (222Rn decay products and the number concentration and size distribution of aerosol particles in the size range of 10–1100 nm were monitored, with the focus on the unattached fraction (fun of radon decay products (RnDPs, a key parameter in radon dosimetry. The total number concentration of aerosols during visits in summer was lower (700 cm−3 than in winter (2800 cm−3, and was dominated by 50 nm particles (related to the attached RnDPs in winter. This explains the higher fun values in summer (0.75 and the lower winter measurement (0.04 and, consequently, DCFD values of 43.6 and 13.1 mSv WLM−1 respectively for the calculated dose conversion factors. The difference is caused by an enhanced inflow of fresh outside air, driven in winter by the higher air temperature in the cave compared to outside, resulting in the introduction of outside aerosol particles into the cave.

  10. Radon decay products and 10-1100 nm aerosol particles in Postojna Cave

    Science.gov (United States)

    Bezek, M.; Gregorič, A.; Vaupotič, J.

    2013-03-01

    At the lowest point along the tourist route in Postojna Cave, the activity concentration of radon (222Rn) decay products and the number concentration and size distribution of aerosol particles in the size range of 10-1100 nm were monitored, with the focus on the unattached fraction (fun) of radon decay products (RnDPs), a key parameter in radon dosimetry. The total number concentration of aerosols during visits in summer was lower (700 cm-3) than in winter (2800 cm-3), and was dominated by 50 nm particles (related to the attached RnDPs) in winter. This explains the higher fun values in summer (0.75) and the lower winter measurement (0.04) and, consequently, DCFD values of 43.6 and 13.1 mSv WLM-1 respectively for the calculated dose conversion factors. The difference is caused by an enhanced inflow of fresh outside air, driven in winter by the higher air temperature in the cave compared to outside, resulting in the introduction of outside aerosol particles into the cave.

  11. Sub-50 nm Scale to Micrometer Scale Soft Lithographic Patterning of Functional Materials

    NARCIS (Netherlands)

    George, A.

    2011-01-01

    This PhD thesis addresses two major issues: 1) Fabricating nanometer-scale patterns of functional materials, 2) Extending the applicability of soft lithographic processes to a wide range of functional materials on conventional silicon substrates and flexible plastic substrates. This thesis describes

  12. Effect of amorphous Mg{sub 50}Ni{sub 50} on hydriding and dehydriding behavior of Mg{sub 2}Ni alloy

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, D., E-mail: danny.guzman@uda.cl [Departamento de Ingenieria en Metalurgia, Facultad de Ingenieria, Universidad de Atacama y Centro Regional de Investigacion y Desarrollo Sustentable de Atacama (CRIDESAT), Av. Copayapu 485, Copiapo (Chile); Ordonez, S. [Departamento de Ingenieria Metalurgica, Facultad de Ingenieria, Universidad de Santiago de Chile, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile); Fernandez, J.F.; Sanchez, C. [Departamento de Fisica de Materiales, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco 28049, Madrid (Spain); Serafini, D. [Departamento de Fisica, Facultad de Ciencias, Universidad de Santiago de Chile and Center for Interdisciplinary Research in Materials, CIMAT, Av. Lib. Bernardo O' Higgins 3363, Santiago (Chile); Rojas, P.A. [Escuela de Ingenieria Mecanica, Facultad de Ingenieria, Av. Los Carrera 01567, Quilpue, Pontificia Universidad Catolica de Valparaiso, PUCV (Chile); Aguilar, C. [Departamento de Ingenieria Metalurgica y Materiales, Universidad Tecnica Federico Santa Maria, Av. Espana 1680, Valparaiso (Chile); Tapia, P. [Departamento de Ingenieria en Metalurgia, Facultad de Ingenieria, Universidad de Atacama, Av. Copayapu 485, Copiapo (Chile)

    2011-04-15

    Composite Mg{sub 2}Ni (25 wt.%) amorphous Mg{sub 50}Ni{sub 50} was prepared by mechanical milling starting with nanocrystalline Mg{sub 2}Ni and amorphous Mg{sub 50}Ni{sub 50} powders, by using a SPEX 8000 D mill. The morphological and microstructural characterization of the powders was performed via scanning electron microscopy and X-ray diffraction. The hydriding characterization of the composite was performed via a solid gas reaction method in a Sievert's-type apparatus at 363 K under an initial hydrogen pressure of 2 MPa. The dehydriding behavior was studied by differential thermogravimetry. On the basis of the results, it is possible to conclude that amorphous Mg{sub 50}Ni{sub 50} improved the hydriding and dehydriding kinetics of Mg{sub 2}Ni alloy upon cycling. A tentative rationalization of experimental observations is proposed. - Research Highlights: {yields} First study of the hydriding behavior of composite Mg{sub 2}Ni (25 wt.%) amorphous Mg{sub 50}Ni{sub 50}. {yields} Microstructural characterization of composite material using XRD and SEM was obtained. {yields} An improved effect of Mg{sub 50}Ni{sub 50} on the Mg{sub 2}Ni hydriding behavior was verified. {yields} The apparent activation energy for the hydrogen desorption of composite was obtained.

  13. Studies on dielectric properties, opto-electrical parameters and electronic polarizability of thermally evaporated amorphous Cd{sub 50}S{sub 50−x}Se{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hassanien, Ahmed Saeed, E-mail: a.s.hassanien@gmail.com [Engineering Mathematics and Physics Department, Faculty of Engineering (Shoubra), Benha University (Egypt); Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia)

    2016-06-25

    The objective of this work is to study the influence of the addition of more Se on dielectric properties, opto-electrical parameters and electronic polarizability of amorphous chalcogenide Cd{sub 50}S{sub 50−x}Se{sub x} thin films (30 ≤ x ≤ 50 at%). Thin films of thickness 200 nm were synthesized by vacuum deposition at ≈8.2 × 10{sup −4} Pa. Both refractive index and extinction coefficient were used to obtain all the studied parameters. The high frequency dielectric constant, real and imaginary parts of dielectric constant were discussed. Drude theory was applied to investigate opto-electrical parameters, like optical carrier concentration, optical mobility and optical resistivity. Moreover, other parameters were investigated and studied, e.g. Drude parameters, volume and surface energy loss functions, dielectric loss factor, dielectric relaxation time, complex optical conductivity and electronic polarizability as well as optical electronegativity and third-order nonlinear optical susceptibility. Values of electronic polarizability and nonlinear optical susceptibility were found to be decreased while optical electronegativity increased as Se-content was increased. Increment of Se-content in amorphous Cd{sub 50}S{sub 50−x}Se{sub x} thin films has also led to minimize the energy losses when electromagnetic waves propagate through films as well as optical conductivity and the speed of light increased. The other studied properties and parameters of Cd{sub 50}S{sub 50−x}Se{sub x} films were found to be strongly dependent upon Se-content. - Highlights: • Thermally evaporated amorphous Cd{sub 50}S{sub 50−x}Se{sub x} (30 ≤ x ≤ 50) thin films were deposited. • Refractive index and absorption index were used to determine almost all properties. • Dielectric properties, Drude parameters and electronic polarizability were studied. • Addition of more Se to CdSSe matrix led to improve the opto-electrical properties. • New data were obtained and

  14. Influence of composition on optical and dispersion parameters of thermally evaporated non-crystalline Cd{sub 50}S{sub 50−x}Se{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hassanien, A.S., E-mail: a.s.hassanien@gmail.com [Engineering Mathematics and Physics Dept., Faculty of Engineering (Shoubra), Benha University (Egypt); Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia); Akl, Alaa A. [Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia)

    2015-11-05

    Non-crystalline thin films of chalcogenide Cd{sub 50}S{sub 50−x}Se{sub x} system (30 ≤ x ≤ 50) were obtained by thermal evaporation technique onto a pre-cleaned glass substrate at a vacuum of 8.2 × 10{sup −4} Pa. The deposition rate and film thickness were kept constant at about 8 nm/s and 200 nm, respectively. Amorphous/crystalline nature and chemical composition of films have been checked using X-ray diffraction and energy dispersive X-ray spectroscopy (EDX). Optical properties of thin films were investigated and studied using the corrected transmittance, T(λ) and corrected reflectance, R(λ) measurements. Obtained data reveal that, the indirect optical energy gap (E{sub g}) was decreased from 2.21 to 1.57 eV. On the contrary, Urbach energy (band tail width), E{sub U} was found to be increased from 0.29 to 0.45 eV. This behavior is believed to be associated with the increase of Se-content instead of S-content in the thin films of Cd{sub 50}S{sub 50−x}Se{sub x} system. Chemical bond approach model, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. Optical density, skin depth, extinction coefficient, refractive index and optical conductivity of chalcogenide CdSSe thin films were discussed as functions of Se-content. Using Wemple-DiDomenico single oscillator model, the refractive index dispersion and energy parameters and their dependence on Se content were studied. - Highlights: • Amorphous thin films of thickness 200 nm of Cd{sub 50}S{sub 50−x}Se{sub x} (30 ≤ x ≤ 50) have prepared. • Optical properties, indirect optical energy gap and band tail width were studied. • Chemical bond approach, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. • New data of dispersion refractive index parameters were investigated and discussed.

  15. Laser-induced damage of fused silica at 355 and 1065 nm initiated at aluminum contamination particles on the surface

    International Nuclear Information System (INIS)

    Genin, F.Y.; Michlitsch, K.; Furr, J.; Kozlowski, M.R.; Krulevitch, P.

    1997-01-01

    1-μm thick circular dots, 10-250 μm dia, were deposited onto 1.14 cm thick fused silica windows by sputtering Al through a mask. Al shavings were also deposited on the windows to investigate effects of particle-substrate adhesion. The silica windows were then illuminated repetitively using a 3-ns, 355 nm and an 8.6-ns, 1064 nm laser. The tests were conducted at near normal incidence with particles on input and output surfaces of the windows. During the first shot, a plasma ignited at the metal particle and damage initiated on the fused silica surface. The morphology of the damage at the metal dots were reproducible but different for input and output surface contamination. For input surface contamination, minor damage occurred where the particle was located; such damage ceased to grow with the removal of contaminant material. More serious damage (pits and cracks) was initiated on the output surface (especially at 355 nm) and grew to catastrophic proportions after few shots. Output surface contaminants were usually ejected on the initial shot, leaving a wave pattern on the surface. No further damage occurred with subsequent shots unless a shot (usually the first shot) cracked the surface; such behavior was mostly observed at 355 nm and occasionally for large shavings at 1064 nm. The size of the damaged area scaled with the size of the particle (except when catastrophic damage occurred). Onset of catastrophic damage on output surface occurred only when particles exceeded a critical size. Damage behavior of the sputtered dots was found to be qualitatively similar to that of the shavings. The artificial contamination technique accelerated the study by allowing better control of the test conditions

  16. Highly (002) textured large grain bcc Cr{sub 80}Mn{sub 20} seed layer on Cr{sub 50}Ti{sub 50} amorphous layer for FePt-C granular film

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Jae, E-mail: jsjigst@ecei.tohoku.ac.jp; Saito, Shin [Department of Electronic Engineering, Tohoku University, 6-6-05 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Hinata, Shintaro [Department of Electronic Engineering, Tohoku University, 6-6-05 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Japan Society for the Promotion of Science Research Fellow (PD), 5-3-1, Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan); Takahashi, Migaku [New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

    2015-05-07

    Effect of bcc Cr{sub 80}Mn{sub 20} seed layer and Cr{sub 50}Ti{sub 50} amorphous texture inducing layer on the heteroepitaxy system in FePt-C granular film was studied by introducing a new concept of the layered structure. The concept suggested that the large grain seed layer in which the crystallographic texture was initially formed on an amorphous layer in the layered structure can reduce the angular distribution of (002) c-axis crystal orientation in the FePt-C granular film owing to heteroepitaxial growth. Structure analysis by X-ray diffraction revealed that (1) when the substrate heating temperature was elevated from 300 °C to 500 °C, grain size in the seed layer increased from 9.8 nm to 11.6 nm, and then decreased with further increasing the substrate temperature. The reduction of the grain size over 500 °C corresponds to the crystallization of the amorphous texture inducing layer, (2) when the grain size increased from 9.8 nm to 11.6 nm, the angular distribution of the (002) orientation in the seed layer dramatically decreased from 13.7° to 4.1°. It was shown that the large grain seed layer increased the perpendicular hysteresis in FePt-C granular film.

  17. Nanoscale morphology of Ni{sub 50}Ti{sub 45}Cu{sub 5} nanoglass

    Energy Technology Data Exchange (ETDEWEB)

    Śniadecki, Z., E-mail: sniadecki@ifmpan.poznan.pl [Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznań (Poland); Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Wang, D. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Ivanisenko, Yu. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Chakravadhanula, V.S.K. [Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Helmholtz Institute Ulm, Helmholtzstraße 11, 89081, Ulm (Germany); Joint Research Laboratory Nanomaterials (KIT-TUD), Institute of Materials Science, TU Darmstadt, Jovanka-Bontschits-Str. 2, 64287 Darmstadt (Germany); Kübel, C. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Karlsruhe Nano Micro Facility, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Hahn, H. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Joint Research Laboratory Nanomaterials (KIT-TUD), Institute of Materials Science, TU Darmstadt, Jovanka-Bontschits-Str. 2, 64287 Darmstadt (Germany); Nanjing University of Science and Technology, Herbert Gleiter Institute of Nanoscience, Building 340, Nanjing, Jiangsu 2 10094 (China); and others

    2016-03-15

    Nanoglasses are noncrystalline solids with a granular nano-/microstructure. In contrast to their nanocrystalline analogs, typically constituted of grains and grain boundaries, nanoglasses consist of glassy regions with a structure corresponding to melt-quenched glasses and amorphous interfaces characterized by a reduced density. Their unique properties can be controlled by modifying size and chemical composition of the granular and interfacial regions. Ni{sub 50}Ti{sub 45}Cu{sub 5} amorphous films were obtained by magnetron sputtering and analyzed to determine their nanoscale morphology and the formation mechanisms. The nanoglasses were noted to have a hierarchical nano-columnar structure with the smallest Ni-rich (Ni:Ti ratio of ca. 5:3) amorphous columns with diameters of about 8 nm and Ti-rich glassy interfacial regions with a substantially lower density. The results were obtained utilizing X-ray diffraction and different microscopic methods, e.g., atomic force microscopy and transmission electron microscopy. A detailed analysis indicates the complexity of the formation mechanisms of topologically and chemically distinguishable structural units with curvature driven surface diffusion, surface mobility, self-shadowing and internal stresses as the most important parameters. Common and simple synthesis method and the possibility for easy modification of the morphology and, consequently, the physical properties offer an opportunity for intensive studies of this new class of materials, opening the way towards possible applications. - Highlights: • Ni{sub 50}Ti{sub 45}Cu{sub 5} thin film nanoglasses were synthesized by magnetron sputtering. • Ti amorphous interfacial phase with reduced density is observed. • Stabilization of interfaces by specific local thermodynamic conditions.

  18. Nucleation and growth of sub-3 nm particles in the polluted urban atmosphere of a megacity in China

    Directory of Open Access Journals (Sweden)

    H. Yu

    2016-03-01

    Full Text Available Particle size distribution down to 1.4 nm was measured in the urban atmosphere of Nanjing, China, in spring, summer, and winter during 2014–2015. Sub-3 nm particle event, which is equivalent to nucleation event, occurred on 42 out of total 90 observation days, but new particles could grow to cloud condensation nuclei (CCN-active sizes on only 9 days. In summer, infrequent nucleation was limited by both unfavorable meteorological conditions (high temperature and relative humidity – RH and reduced anthropogenic precursor availability due to strict emission control measures during the 2014 Youth Olympic Games in Nanjing. The limiting factors for nucleation in winter and spring were meteorological conditions (radiation, temperature, and RH and condensation sink, but for the further growth of sub-3 nm particles to CCN-active sizes, anthropogenic precursors again became limiting factors. Nucleation events were strong in the polluted urban atmosphere. Initial J1.4 at the onset and peak J1.4 at the noontime could be up to 2.1 × 102 and 2.5 × 103 cm−3 s−1, respectively, during the eight nucleation events selected from different seasons. Time-dependent J1.4 usually showed good linear correlations with a sulfuric acid proxy for every single event (R2 = 0.56–0.86, excluding a day with significant nocturnal nucleation, but the correlation among all eight events deteriorated (R2 =  0.17 due to temperature or season change. We observed that new particle growth rate (GR did not increase monotonically with particle size, but had a local maximum up to 25 nm h−1 between 1 and 3 nm. The existence of local maxima GR in sub-3 nm size range, though sensitive to measurement uncertainties, gives new insight into cluster dynamics in polluted environments. In this study such growth rate behavior was interpreted as the solvation effect of organic activating vapor in newly formed inorganic nuclei.

  19. Effects of 20–100 nm particles on liquid clouds in the clean summertime Arctic

    Directory of Open Access Journals (Sweden)

    W. R. Leaitch

    2016-09-01

    Full Text Available Observations addressing effects of aerosol particles on summertime Arctic clouds are limited. An airborne study, carried out during July 2014 from Resolute Bay, Nunavut, Canada, as part of the Canadian NETCARE project, provides a comprehensive in situ look into some effects of aerosol particles on liquid clouds in the clean environment of the Arctic summer. Median cloud droplet number concentrations (CDNC from 62 cloud samples are 10 cm−3 for low-altitude cloud (clouds topped below 200 m and 101 cm−3 for higher-altitude cloud (clouds based above 200 m. The lower activation size of aerosol particles is  ≤  50 nm diameter in about 40 % of the cases. Particles as small as 20 nm activated in the higher-altitude clouds consistent with higher supersaturations (S for those clouds inferred from comparison of the CDNC with cloud condensation nucleus (CCN measurements. Over 60 % of the low-altitude cloud samples fall into the CCN-limited regime of Mauritsen et al. (2011, within which increases in CDNC may increase liquid water and warm the surface. These first observations of that CCN-limited regime indicate a positive association of the liquid water content (LWC and CDNC, but no association of either the CDNC or LWC with aerosol variations. Above the Mauritsen limit, where aerosol indirect cooling may result, changes in particles with diameters from 20 to 100 nm exert a relatively strong influence on the CDNC. Within this exceedingly clean environment, as defined by low carbon monoxide and low concentrations of larger particles, the background CDNC are estimated to range between 16 and 160 cm−3, where higher values are due to activation of particles  ≤  50 nm that likely derive from natural sources. These observations offer the first wide-ranging reference for the aerosol cloud albedo effect in the summertime Arctic.

  20. Angular distributions of emitted particles by laser ablation of silver at 355 nm

    DEFF Research Database (Denmark)

    Svendsen, Winnie Edith; Schou, Jørgen; Hansen, T.

    1998-01-01

    The angular distribution of laser ablated silver in vacuum has been measured in situ with an array of quartz-crystal microbalances. The silver surface was irradiated by ns pulses from a Nd:YAG laser operating at 355 nm for fluences ranging from 0.7 J/cm2 to 8 J/cm2. The distribution is strongly...... peaked in the forward direction corresponding to cosp/, where p varies from 5 to 12 for the largest beam spot, but is less peaked for the smallest beam spots. The total collected yield of ablated atoms is about 221015 Ag atoms per pulse for the highest pulse energies....

  1. WWW scattering matrix database for small mineral particles at 441.6 and 632.8 nm

    International Nuclear Information System (INIS)

    Volten, H.; Munoz, O.; Hovenier, J.W.; Haan, J.F. de; Vassen, W.; Zande, W.J. van der; Waters, L.B.F.M.

    2005-01-01

    We present a new extensive database containing experimental scattering matrix elements as functions of the scattering angle measured at 441.6 and 632.8 nm for a large collection of micron-sized mineral particles in random orientation. This unique database is accessible through the World-Wide Web. Size distribution tables of the particles are also provided, as well as other characteristics relevant to light scattering. The database provides the light scattering community with easily accessible information that is useful, for a variety of applications such as testing theoretical methods, and the interpretation of measurements of scattered radiation. To illustrate the use of the database, we consider cometary observations and compare them with (1) cometary analog data from the database, and (2) with results of Mie calculations for homogeneous spheres, having the same refractive index and size distribution as those of the analog data

  2. Comparative Study by MS and XRD of Fe{sub 50}Al{sub 50} Alloys Produced by Mechanical Alloying, Using Different Ball Mills

    Energy Technology Data Exchange (ETDEWEB)

    Rojas Martinez, Y., E-mail: yarojas@ut.edu.co [University of Tolima, Department of Physics (Colombia); Perez Alcazar, G. A. [University of Valle, Department of Physics (Colombia); Bustos Rodriguez, H.; Oyola Lozano, D., E-mail: doyolalozano@yahoo.com.mx [University of Tolima, Department of Physics (Colombia)

    2005-02-15

    In this work we report a comparative study of the magnetic and structural properties of Fe{sub 50}Al{sub 50} alloys produced by mechanical alloying using two different planetary ball mills with the same ball mass to powder mass relation. The Fe{sub 50}Al{sub 50} sample milled during 48 h using the Fritsch planetary ball mill pulverisette 5 and balls of 20 mm, presents only a bcc alloy phase with a majority of paramagnetic sites, whereas that sample milled during the same time using the Fritsch planetary ball mill pulverisette 7 with balls of 15 mm, presents a bcc alloy phase with paramagnetic site (doublet) and a majority of ferromagnetic sites which include pure Fe. However for 72 h of milling this sample presents a bcc paramagnetic phase, very similar to that prepared with the first system during 48 h. These results show that the conditions used in the first ball mill equipment make more efficient the milling process.

  3. Structural and magnetic properties of Mn{sub 50}Fe{sub 50−x}Sn{sub x} (x=10, 15 and 20) alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Tanmoy [LCMP, S.N. Bose National Centre for Basic Sciences, Kolkata 700106 (India); Agarwal, Sandeep [Haldia Institute of Technology, Haldia 721657 (India); Mukhopadhyay, P.K., E-mail: pkm@bose.res.in [LCMP, S.N. Bose National Centre for Basic Sciences, Kolkata 700106 (India)

    2016-11-15

    In this work we report measurements and comparisons of the structural, magnetic and transport properties of a series of Mn{sub 50}Fe{sub 50−x}Sn{sub x} alloys (x=10, 15 and 20). We found that while the lower Sn composition sample stabilized in β-Mn-type crystallographic phase, the higher Sn composition alloys contained both β-Mn-type as well as Mn{sub 3}Sn-type hexagonal DO{sub 19} phases. Through d.c. and a.c. magnetic property measurements we have established the existence of a ferromagnetic transition near room temperature followed by a spin reorientation at lower temperature in the Mn{sub 3}Sn-type crystallographic phase of the alloys. Our resistivity study also revealed an interesting behavior with negative temperature coefficient (TCR) in these alloys. - Highlights: • Mn{sub 50}Fe{sub 50-x}Sn{sub x} alloys were studied over a limited concentration range. • Lower Sn alloys behaved similar to ß-Mn alloys both structurally and magnetically. • Higher Sn alloys showed magnetic transitions similar to Mn{sub 3}Sn and Fe{sub 3}Sn. • Resistivity showed bad metallic behavior with negetive temperature coefficient.

  4. Investigation of the magnetic phase transition in thin Fe{sub 50}Pt{sub 50-x}Rh{sub x} films by neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, Jochen; Lott, Dieter; Schreyer, Andreas [GKSS Research Centre, Geesthacht (Germany); Mankey, Gary J. [MINT Center, The University of Alabama, Tuscaloosa, AL (United States); Schmidt, Wolfgang; Schmalzl, Karin [JCNS, Juelich (Germany)

    2008-07-01

    In the last years perpendicular recording plays a major role in the development of novel magnetic data storage. Here, materials with high anisotropy are used which delivers good thermal stability. However in order to write the bits a high magnetic field is necessary. By the use of soft underlayers the write field can be significant reduced. Fe{sub 50}Pt{sub 50-x}Rh{sub x} is a promising candidate for such an underlayer. Magnetization measurements of the bulk samples for x=10 refer to a antiferromagnetic (AF)/ferromagnetic (FM) phase transition at about 150 K when heated. Additional magnetostriction measurements indicate that the phase transition could also be induced by applying a magnetic field. The FM state lowers the high anisotropy and therefore the high write field. The AF state helps to stabilize the recording media via exchange interaction. For technical applications the use of thin films are essential to save space and costs for the next generation of magnetic storage devices. Here we present results on several thin Fe{sub 50}Pt{sub 50-x}Rh{sub x} films with different concentration of Rh. The films were examined by polarized and unpolarized neutron diffraction in dependence of temperature and magnetic field.

  5. Laboratory observations of temperature and humidity dependencies of nucleation and growth rates of sub-3 nm particles

    Science.gov (United States)

    Yu, Huan; Dai, Liang; Zhao, Yi; Kanawade, Vijay P.; Tripathi, Sachchida N.; Ge, Xinlei; Chen, Mindong; Lee, Shan-Hu

    2017-02-01

    Temperature and relative humidity (RH) are the most important thermodynamic parameters in aerosol formation, yet laboratory studies of nucleation and growth dependencies on temperature and RH are lacking. Here we report the experimentally observed temperature and RH dependences of sulfuric acid aerosol nucleation and growth. Experiments were performed in a flow tube in the temperature range from 248 to 313 K, RH from 0.8% to 79%, and relative acidity (RA) of sulfuric acid from 6 × 10-5 to 0.38 (2 × 107-109 cm-3). The impurity levels of base compounds were determined to be NH3 nucleation at fixed sulfuric acid concentration but impede nucleation when RA is fixed. It is also shown that binary nucleation of sulfuric acid and water is negligible in planetary boundary layer temperature and sulfuric acid ranges. An empirical algorithm was derived to correlate the nucleation rate with RA, RH, and temperature together. Collision-limited condensation of free-sulfuric acid molecules fails to predict the observed growth rate in the sub-3 nm size range, as well as its dependence on temperature and RH. This suggests that evaporation, sulfuric acid hydration, and possible involvement of other ternary molecules should be considered for the sub-3 nm particle growth.

  6. Size distributions of non-volatile particle residuals (Dp<800 nm at a rural site in Germany and relation to air mass origin

    Directory of Open Access Journals (Sweden)

    T. Tuch

    2007-11-01

    Full Text Available Atmospheric aerosol particle size distributions at a continental background site in Eastern Germany were examined for a one-year period. Particles were classified using a twin differential mobility particle sizer in a size range between 3 and 800 nm. As a novelty, every second measurement of this experiment involved the removal of volatile chemical compounds in a thermodenuder at 300°C. This concept allowed to quantify the number size distribution of non-volatile particle cores – primarily associated with elemental carbon, and to compare this to the original non-conditioned size distribution. As a byproduct of the volatility analysis, new particles originating from nucleation inside the thermodenuder can be observed, however, overwhelmingly at diameters below 6 nm. Within the measurement uncertainty, every particle down to particle sizes of 15 nm is concluded to contain a non-volatile core. The volume fraction of non-volatile particulate matter (non-conditioned diameter < 800 nm varied between 10 and 30% and was largely consistent with the experimentally determined mass fraction of elemental carbon. The average size of the non-volatile particle cores was estimated as a function of original non-conditioned size using a summation method, which showed that larger particles (>200 nm contained more non-volatile compounds than smaller particles (<50 nm, thus indicating a significantly different chemical composition. Two alternative air mass classification schemes based on either, synoptic chart analysis (Berliner Wetterkarte or back trajectories showed that the volume and number fraction of non-volatile cores depended less on air mass than the total particle number concentration. In all air masses, the non-volatile size distributions showed a more and a less volatile ("soot" mode, the latter being located at about 50 nm. During unstable conditions and in maritime air masses, smaller values were observed compared to stable or continental conditions

  7. Influence of physical properties and chemical composition of sample on formation of aerosol particles generated by nanosecond laser ablation at 213 nm

    Energy Technology Data Exchange (ETDEWEB)

    Hola, Marketa, E-mail: mhola@sci.muni.c [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Konecna, Veronika [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Mikuska, Pavel [Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic v.v.i., Veveri 97, 602 00 Brno (Czech Republic); Kaiser, Jozef [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Kanicky, Viktor [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic)

    2010-01-15

    The influence of sample properties and composition on the size and concentration of aerosol particles generated by nanosecond Nd:YAG laser ablation at 213 nm was investigated for three sets of different materials, each containing five specimens with a similar matrix (Co-cemented carbides with a variable content of W and Co, steel samples with minor differences in elemental content and silica glasses with various colors). The concentration of ablated particles (particle number concentration, PNC) was measured in two size ranges (10-250 nm and 0.25-17 mum) using an optical aerosol spectrometer. The shapes and volumes of the ablation craters were obtained by Scanning Electron Microscopy (SEM) and by an optical profilometer, respectively. Additionally, the structure of the laser-generated particles was studied after their collection on a filter using SEM. The results of particle concentration measurements showed a significant dominance of particles smaller than 250 nm in comparison with larger particles, irrespective of the kind of material. Even if the number of particles larger than 0.25 mum is negligible (up to 0.1%), the volume of large particles that left the ablation cell can reach 50% of the whole particle volume depending on the material. Study of the ablation craters and the laser-generated particles showed a various number of particles produced by different ablation mechanisms (particle splashing or condensation), but the similar character of released particles for all materials was observed by SEM after particle collection on the membrane filter. The created aerosol always consisted of two main structures - spherical particles with diameters from tenths to units of micrometers originally ejected from the molten surface layer and mum-sized 'fibres' composed of primary agglomerates with diameters in the range between tens and hundreds of nanometers. The shape and structure of ablation craters were in good agreement with particle concentration

  8. Evidence of magnetic dipolar interaction in micrometric powders of the Fe{sub 50}Mn{sub 10}Al{sub 40} system: Melted alloys

    Energy Technology Data Exchange (ETDEWEB)

    Perez Alcazar, G.A., E-mail: gpgeperez@gmail.com [Departamento de Fisica, Universidad del Valle, A. A. 25360, Cali (Colombia); Unidad Asociada ICMM-IMA, Apdo. 155, 28230 Las Rozas, Madrid (Spain); Zamora, L.E. [Departamento de Fisica, Universidad del Valle, A. A. 25360, Cali (Colombia); Unidad Asociada ICMM-IMA, Apdo. 155, 28230 Las Rozas, Madrid (Spain); Tabares, J.A.; Piamba, J.F. [Departamento de Fisica, Universidad del Valle, A. A. 25360, Cali (Colombia); Gonzalez, J.M. [Unidad Asociada ICMM-IMA, Apdo. 155, 28230 Las Rozas, Madrid (Spain); Greneche, J.M. [LUNAM, Universite du Maine, Institut des Molecules et Materiaux du Mans, UMR CNRS 6283, 72085 Le Mans Cedex 9 (France); Martinez, A. [Instituto de Magnetismo Aplicado, P.O. Box 155, 28230 Las Rozas (Spain); Romero, J.J. [Instituto de Ceramica y Vidrio, CSIC, C/Kelsen 5, 28049, Madrid (Spain); Marco, J.F. [Instituto de Quimica Fisica Rocasolano, CSIC, C/Serrano 119, 28006 Madrid (Spain)

    2013-02-15

    Powders of melted disordered Fe{sub 50}Mn{sub 10}Al{sub 40} alloy were separated at different mean particle sizes as well as magnetically and structurally characterized. All the samples are BCC and show the same nanostructure. Particles larger than 250 {mu}m showed a lamellar shape compared to smaller particles, which exhibited a more regular form. All the samples are ferromagnetic at room temperature and showed reentrant spin-glass (RSG) and superparamagnetic (SP)-like behaviors between 30 and 60 K and 265 and > 280 K, respectively, as a function of frequency and particle size. The freezing temperature increases with increasing particle size while the blocking one decreases with particle size. The origin of these magnetic phenomena relies in the internal disordered character of samples and the competitive interaction of Fe and Mn atoms. The increase of their critical freezing temperature with increasing mean particle size is due to the increase of the magnetic dipolar interaction between the magnetic moment of each particle with the field produced by the other magnetic moments of their surrounding particles. - Highlights: Black-Right-Pointing-Pointer The effect of particle size in microsized powders of Fe{sub 50}Mn{sub 10}Al{sub 40} melted disordered alloy is studied. Black-Right-Pointing-Pointer Dipolar magnetic interaction between particles exists and this changes with the particle size. Black-Right-Pointing-Pointer For all the particle sizes the reentrant spin- glass and the superparamagnetic-like phases exist. Black-Right-Pointing-Pointer RSG and SP critical temperatures increase with increasing the dipolar magnetic interaction (the mean particle size).

  9. Microwave absorption properties of lightweight absorber based on Fe{sub 50}Ni{sub 50}-coated poly(acrylonitrile) microspheres and reduced graphene oxide composites

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bin [School of Material Science And Engineering, Wuhan University of Technology, Wuhan 430070 (China); Wang, Jun, E-mail: wgdfrp@whut.edu.cn [School of Material Science And Engineering, Wuhan University of Technology, Wuhan 430070 (China); Wang, Junpeng; Huo, Siqi [School of Material Science And Engineering, Wuhan University of Technology, Wuhan 430070 (China); Zhang, Bin [School of Science, Wuhan University of Technology, Wuhan 430070 (China); Tang, Yushan [School of Material Science And Engineering, Wuhan University of Technology, Wuhan 430070 (China)

    2016-09-01

    In this paper, we proposed a facile method to obtain the lightweight composites consisting of surface modified Fe{sub 50}Ni{sub 50}-coated poly(acrylonitrile) microspheres (PANS@SMF), reduced graphene oxide (RGO) and epoxy resin. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM) and vector network analyzer (VNA). Impedance matching condition and electromagnetic wave attenuation characteristic were used for the reflection loss (RL) performance of the composites. Compared with pure PANS@SMF and RGO composites, the −10 dB absorption bandwidth and the minimum RL of the hybrid composites were enhanced. The bandwidth less than −10 dB was almost 4.5 GHz in the range of 10 GHz to 14.5 GHz, with a matching thickness of 2.5 mm. The density of the hybrid composites was in the range of 0.25–0.34 g/cm{sup 3}. Therefore, the hybrid composite can be considered as a potential lightweight microwave absorber. - Highlights: • PANS@SMF – RGO epoxy composite was fabricated by a facile method. • The absorption bandwidth less than −10 dB can reach up to 4.5 GHz with layer thickness of 2.5 mm. • The density of the composites is in the range of 0.25–0.34 g/cm{sup 3} and can be considered as a lightweight microwave absorber.

  10. Determining the size and concentration dependence of gold nanoparticles in vitro cytotoxicity (IC{sub 50}) test using WST-1 assay

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Nur Shafawati binti; Rahman, Azhar Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Aziz, Azlan Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Shamsuddin, Shaharum [Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2015-04-24

    Gold nanoparticles (AuNPs) received a great deal of attention for biomedical applications, especially in diagnostic imaging and therapeutics. Even though AuNPs have potential benefits in biomedical applications, the impact of AuNPs on human and environmental health still remains unclear. The use of AuNPs which is a high-atomic-number materials, provide advantages in terms of radiation dose enhancement. However, before this can become a clinical reality, cytotoxicity of the AuNPs has to be carefully evaluated. Cytotoxicity test is a rapid, standardized test that is very sensitive to determine whether the nanoparticles produced are harmful or benign on cellular components. In this work the size and concentration dependence of AuNPs cytotoxicity in breast cancer cell lines (MCF-7) are tested by using WST-1 assay. The sizes of AuNPs tested were 13 nm, 50 nm, and 70 nm. The cells were seeded in the 96-well plate and were treated with different concentrations of AuNPs by serial dilution for each size of AuNPs. The high concentration of AuNPs exhibit lower cell viability compared to low concentration of AuNPs. We quantified the toxicity of AuNPs in MCF-7 cell lines by determining the IC{sub 50} values in WST-1 assays. The IC{sub 50} values (inhibitory concentrations that effected 50% growth inhibition) of 50 nm AuNPs is lower than 13 nm and 70 nm AuNPs. Mean that, 50nm AuNPs are more toxic to the MCF-7 cells compared to smaller and larger sizes AuNPs. The presented results clearly indicate that the cytotoxicity of AuNPs depend not only on the concentration, but also the size of the nanoparticles.

  11. Properties of aerosol particles generated during 213 nm laser ablation: a study of compact and powdered tungsten carbides as materials with a two-component matrix

    International Nuclear Information System (INIS)

    Hola, M.; Konecna, V.; Kanicky, V.; Mikuska, P.; Kaiser, J.; Hanzlikova, R.

    2009-01-01

    Full text: The laser ablation process of tungsten carbide hardmetals was studied using 213 nm Nd:YAG laser. The samples were presented for ablation as sintered compacts or powders pressed into pellets to compare the generation of particles from samples with similar chemical composition but different physical properties. The influence of laser ablation parameters on the aerosol generation was studied using an optical aerosol spectrometer. In the case of powders, the effect of binder amount was investigated. The structure of generated particles and the properties of ablation-craters were additionally studied by SEM. (author)

  12. Direct Write Processing of Multi-micron Thickness Copper Nano-particle Paste on Flexible Substrates with 532 nm Laser Wavelength

    Science.gov (United States)

    Lopez-Espiricueta, Dunia; Fearon, Eamonn; Edwardson, Stuart; Dearden, Geoffrey

    The Laser Assisted Direct Write (LA-DW) method has been implemented in the development of different markets and material processing, recently also used for creating Printed Circuit Boards (PCB) or electrical circuitry. The process consists in the deposition of metallic nano-particle (NP) inks, which are afterwards cured or sintered by laser irradiation, thus creating conductive pathways; advantages are speed, accuracy and the protection of the heat affected zone (HAZ). This research will study the behaviour of the heat dissipation relatively within the Nano-particle Copper paste after being irradiated with 1064 nm and 532 nm wavelengths, research will be developed on different widths and depths deposited onto flat surfaces such as flexible PET. Comparisons to be made between resistivity results obtained from different wavelengths.

  13. EUV blank defect and particle inspection with high throughput immersion AFM with 1nm 3D resolution

    NARCIS (Netherlands)

    Es, M.H. van; Sadeghian Marnani, H.

    2016-01-01

    Inspection of EUV mask substrates and blanks is demanding. We envision this is a good target application for massively parallel Atomic Force Microscopy (AFM). We envision to do a full surface characterization of EUV masks with AFM enabling 1nm true 3D resolution over the entire surface. The limiting

  14. Heat treatment and thickness-dependent electrical study of Se{sub 50}Te{sub 20}S{sub 30} thin film

    Energy Technology Data Exchange (ETDEWEB)

    Abd-Elrahman, M.I.; Hafiz, M.M.; Qasem, Ammar; Abdel-Rahim, M.A. [Assiut University, Physics Department, Faculty of Science, Assiut (Egypt)

    2016-08-15

    Chalcogenide Se{sub 50}Te{sub 20}S{sub 30} thin film of different thickness was deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se{sub 50}Te{sub 20}S{sub 30} was obtained using a differential scanning calorimetry (DSC) with heating rate of 7.5 K/min. The glass transition temperature T{sub g}, crystallization temperature T{sub c} and peak crystallization temperature T{sub p} were identified. The X-ray diffraction (XRD) examination indicates the amorphous nature of the as-deposited film and polycrystalline structure of the thermal annealed ones. The dark electrical resistivity (ρ) measurements were taken in temperature range (300-500 K) and thickness range (200-450 nm). Analysis of the electrical resistivity results revealed two types of conduction mechanisms: conduction due to extended states in the temperature range (T > T{sub c}) and variable range hopping in the temperature range (T < T{sub c}). The effect of the heat treatment and thickness on the density of localized states at the Fermi level N(E{sub F}) and hopping parameters were studied. (orig.)

  15. Determination of gamma radiation lethal dose (LD{sub 50}) and resveratrol cytotoxicity level in tumor cells line

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cruz, Aurea S. [Instituto Adolfo Lutz (IAL-SP) Secao de Culturas Celulares, SP (Brazil)

    2011-07-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD{sub 50}) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC{sub 50%} in NCI-H292 cells was 192{mu}M and in RD cells was 128{mu}M; and RD cells gamma radiation LD{sub 50} was 435Gy. (author)

  16. Saddle-fin cell transistors with oxide etch rate control by using tilted ion implantation (TIS-fin) for sub-50-nm DRAMs

    International Nuclear Information System (INIS)

    Yoo, Min Soo; Choi, Kang Sik; Sun, Woo Kyung

    2010-01-01

    As DRAM cell pitch size decreases, the need for a high performance transistor is increasing. Though saddle-fin (S-fin) transistors have superior characteristics, S-fin transistors are well known to be more sensitive to process variation. To make uniform S-fin transistors, for the first time, we developed a new fin formation method using tilted ion implantation along the wordline direction after a recess gate etch. Due to the increased etch rate of the oxide film by ion implantation damage, fins are made at the bottom channel of the recess gate after wet etching. The resulting tilt implanted saddle-fin (TIS-fin) transistor has remarkably improved characteristics, such as ∼8% subthreshold swing (SS) and a 40% drain induced barrier lowering (DIBL) decrease. Especially, the TIS-fin with a neutral dopant has a reduced threshold voltage (Vth) variation within a wafer (<100 mV), which is comparable with that of a mass-produced sphere-shaped recessed channel array transistor (SRCAT).

  17. Sub-50 fs excited state dynamics of 6-chloroguanine upon deep ultraviolet excitation.

    Science.gov (United States)

    Mondal, Sayan; Puranik, Mrinalini

    2016-05-18

    The photophysical properties of natural nucleobases and their respective nucleotides are ascribed to the sub-picosecond lifetime of their first singlet states in the UV-B region (260-350 nm). Electronic transitions of the ππ* type, which are stronger than those in the UV-B region, lie at the red edge of the UV-C range (100-260 nm) in all isolated nucleobases. The lowest energetic excited states in the UV-B region of nucleobases have been investigated using a plethora of experimental and theoretical methods in gas and solution phases. The sub-picosecond lifetime of these molecules is not a general attribute of all nucleobases but specific to the five primary nucleobases and a few xanthine and methylated derivatives. To determine the overall UV photostability, we aim to understand the effect of more energetic photons lying in the UV-C region on nucleobases. To determine the UV-C initiated photophysics of a nucleobase system, we chose a halogen substituted purine, 6-chloroguanine (6-ClG), that we had investigated previously using resonance Raman spectroscopy. We have performed quantitative measurements of the resonance Raman cross-section across the Bb absorption band (210-230 nm) and constructed the Raman excitation profiles. We modeled the excitation profiles using Lee and Heller's time-dependent theory of resonance Raman intensities to extract the initial excited state dynamics of 6-ClG within 30-50 fs after photoexcitation. We found that imidazole and pyrimidine rings of 6-ClG undergo expansion and contraction, respectively, following photoexcitation to the Bb state. The amount of distortions of the excited state structure from that of the ground state structure is reflected by the total internal reorganization energy that is determined at 112 cm(-1). The contribution of the inertial component of the solvent response towards the total reorganization energy was obtained at 1220 cm(-1). In addition, our simulation also yields an instantaneous response of the first

  18. Low temperature study of micrometric powder of melted Fe{sub 50}Mn{sub 10}Al{sub 40} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zamora, Ligia E. [Departamento de Fisica, Universidad del Valle, A. A. 25360 Cali (Colombia); Perez Alcazar, G.A., E-mail: gpgeperez@gmail.com [Departamento de Fisica, Universidad del Valle, A. A. 25360 Cali (Colombia); Tabares, J.A. [Departamento de Fisica, Universidad del Valle, A. A. 25360 Cali (Colombia); Romero, J.J. [Instituto de Ceramica y Vidrio, CSIC, C/Kelsen 5, 28049 Madrid (Spain); Martinez, A. [Instituto de Magnetismo Aplicado, P.O. Box 155, Las Rozas, 28230 Madrid (Spain); Gonzalez, J.M. [Unidad Asociada ICMM-IMA, c/Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain); Palomares, F.J. [Instituto de Ciencia de Materiales de Madrid, CSIC, C/Sor Juana Ines de la Cruz, 28049 Cantoblanco, Madrid (Spain); Marco, J.F. [Instituto de Quimica-Fisica Rocasolano, CSIC, c/Serrano 119, 28006 Madrid (Spain)

    2012-06-15

    Melted Fe{sub 50}Mn{sub 10}Al{sub 40} alloy powder with particle size less than 40 {mu}m was characterized at room temperature by XRD, SEM and XPS; and at low temperatures by Moessbauer spectrometry, ac susceptibility, and magnetization analysis. The results show that the sample is BCC ferromagnetic but with a big contribution of paramagnetic sites, and presents super-paramagnetic and re-entrant spin-glass phases with critical temperatures of 265 and 35 K, respectively. The presence of the different phases detected is due to the disordered character of the sample and the competitive magnetic interactions. The obtained values of the saturation magnetization and the coercive field as a function of temperature present a behavior which indicates a ferromagnetic phase. However, the behavior of the FC curve and that of the coercive field as a function of temperature suggest that the dipolar magnetic interaction between particles contributes to the internal magnetic field in the same way as was reported for nanoparticulate powders.

  19. Particle emission from polymer-doped water ice matrices induced by non-linear absorption of laser light at 1064 nm

    DEFF Research Database (Denmark)

    Purice, A.; Schou, Jørgen; Dinescu, M.

    2006-01-01

    Emission of PEG (polyethylene glycol) molecules and ions from an ice target induced by laser irradiation in the infrared (IR) regime at 1064 nm was studied. Matrices of 1 wt% PEG flash-frozen solutions were used for polymer deposition with MAPLE (matrix assisted pulsed laser evaporation). Even...

  20. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC{sub 50} values of other test models

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S., E-mail: bkhangarot@hotmail.com [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India); Das, Sangita [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2009-12-30

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC{sub 50}) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC{sub 50} values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r{sup 2}) for 17 physicochemical properties of metals or metal ions and EC{sub 50}s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK{sub sp}), softness parameter and some other physicochemical characteristics were significantly correlated with EC{sub 50}s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC{sub 50}s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  1. Influence of spark plasma sintering parameters on the mechanical properties of Cu{sub 50}Zr{sub 45}Al{sub 5} bulk metallic glass obtained using metallic glass powder

    Energy Technology Data Exchange (ETDEWEB)

    Cardinal, S. [Université de Lyon, CNRS (France); INSA-Lyon, MATEIS UMR5510, F-69621 Villeurbanne (France); Pelletier, J.M., E-mail: jean-marc.pelletier@insa-lyon.fr [Université de Lyon, CNRS (France); INSA-Lyon, MATEIS UMR5510, F-69621 Villeurbanne (France); Qiao, J.C. [School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi’an 710072 (China); Bonnefont, G. [Université de Lyon, CNRS (France); INSA-Lyon, MATEIS UMR5510, F-69621 Villeurbanne (France); Xie, G. [Institute for Materials Research, Tohoku University, Sendai (Japan)

    2016-11-20

    Gas atomized Cu{sub 50}Zr{sub 45}Al{sub 5} amorphous powder was densified by spark plasma sintering, in order to obtain bulk metallic glasses with larger size than that obtained by the conventional casting strategy. The influence of different parameters was investigated: sintering temperature, isothermal holding time as well as size of the specimens. After optimization of the processing parameters, dense and amorphous specimens were elaborated with a diameter up to 30 mm. Thermal stability and mechanical properties of consolidated samples are similar to those of Cu{sub 50}Zr{sub 45} Al{sub 5} cast alloy. A hardness of 535 HV and a compressive strength of 1600 MPa have been obtained. Fractographic investigation indicated an intergranular rupture mode which leads to lower toughness compared to as the cast material, but for these samples the size is limited to 3 mm. However an increase in applied pressure (from 90 MPa to 1 GPa) induces a significant improvement in bonding between powder particles.

  2. Experimental determination of the steady-state charging probabilities and particle size conservation in non-radioactive and radioactive bipolar aerosol chargers in the size range of 5–40 nm

    Energy Technology Data Exchange (ETDEWEB)

    Kallinger, Peter, E-mail: peter.kallinger@univie.ac.at; Szymanski, Wladyslaw W. [University of Vienna, Faculty of Physics (Austria)

    2015-04-15

    Three bipolar aerosol chargers, an AC-corona (Electrical Ionizer 1090, MSP Corp.), a soft X-ray (Advanced Aerosol Neutralizer 3087, TSI Inc.), and an α-radiation-based {sup 241}Am charger (tapcon & analysesysteme), were investigated on their charging performance of airborne nanoparticles. The charging probabilities for negatively and positively charged particles and the particle size conservation were measured in the diameter range of 5–40 nm using sucrose nanoparticles. Chargers were operated under various flow conditions in the range of 0.6–5.0 liters per minute. For particular experimental conditions, some deviations from the chosen theoretical model were found for all chargers. For very small particle sizes, the AC-corona charger showed particle losses at low flow rates and did not reach steady-state charge equilibrium at high flow rates. However, for all chargers, operating conditions were identified where the bipolar charge equilibrium was achieved. Practically, excellent particle size conservation was found for all three chargers.

  3. Superimposition of carbon dioxide on acute isobaric hypoxia: plasma erythropoietin, acid-base status, and P/sub 50/ in the unanesthetized rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Wolf-Priessnitz, J.

    1978-06-01

    Major factors affecting changes of the arterial Hb--O/sub 2/ affinity (P/sub 50/) were examined in relation to the initiation of erythropoietin (ESF) production in unanesthetized New Zealand white male rabbits. They were exposed to an isobaric hypoxic environment (8.8 percent O/sub 2/) with and without CO/sub 2/ (5.6 percent or 10 percent). During 5 hrs exposure, samples of arterial blood were collected for measurements of plasma ESF titers; whole-blood pH, P/sub CO2/, S/sub O2/, lactate, pyruvate, and P/sub 50/; and intraerythrocytic 2,3-DPG, ATP and ADP. Exposure to 8.8 percent oxygen alone stimulated ESF production and caused a leftward shift in the in vivo P/sub 50/; the addition of CO/sub 2/ significantly inhibited ESF production and blocked the shift in P/sub 50//sub (i.v.)/. The data suggest that increased oxygenation of the whole-body tissues occurs with exposure to 8.8 percent O/sub 2/ + CO/sub 2/ as reflected by lower whole-blood excess lactate accumulation. In keeping with the prevailing theory, the suppression of ESF production is probably a result of this increased oxygenation.

  4. Experimental characterization of the COndensation PArticle counting System for high altitude aircraft-borne application

    Directory of Open Access Journals (Sweden)

    S. Borrmann

    2009-06-01

    Full Text Available A characterization of the ultra-fine aerosol particle counter COPAS (COndensation PArticle counting System for operation on board the Russian high altitude research aircraft M-55 Geophysika is presented. The COPAS instrument consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs operated with the chlorofluorocarbon FC-43. It operates at pressures between 400 and 50 hPa for aerosol detection in the particle diameter (dp range from 6 nm up to 1 μm. The aerosol inlet, designed for the M-55, is characterized with respect to aspiration, transmission, and transport losses. The experimental characterization of counting efficiencies of three CPCs yields dp50sub> (50% detection particle diameter of 6 nm, 11 nm, and 15 nm at temperature differences (ΔT between saturator and condenser of 17°C, 30°C, and 33°C, respectively. Non-volatile particles are quantified with a fourth CPC, with dp50=11 nm. It includes an aerosol heating line (250°C to evaporate H2SO4-H2O particles of 11 nm<dp<200 nm at pressures between 70 and 300 hPa. An instrumental in-flight inter-comparison of the different COPAS CPCs yields correlation coefficients of 0.996 and 0.985. The particle emission index for the M-55 in the range of 1.4–8.4×1016 kg−1 fuel burned has been estimated based on measurements of the Geophysika's own exhaust.

  5. Low energy states of {sub 31}{sup 81}Ga{sub 50}: Elements on the doubly-magic nature of {sup 78}Ni

    Energy Technology Data Exchange (ETDEWEB)

    Verney, D. [Institut de Physique Nucleaire CNRS-IN2P3/Univ. Paris Sud-XI, F-91406 Orsay Cedex (France)]|[GANIL, BP 55027, F-14076 Caen Cedex 5 (France); Ibrahim, F.; Bourgeois, C. [Institut de Physique Nucleaire CNRS-IN2P3/Univ. Paris Sud-XI, F-91406 Orsay Cedex (France)] (and others)

    2007-01-15

    Excited levels were attributed to {sub 31}{sup 81}Ga{sub 50} for the first time which were fed in the {beta} decay of its mother nucleus {sup 81}Zn produced in the fission of {sup nat}U using the ISOL technique. We show that the structure of this nucleus is consistent with that of the less exotic proton-deficient N 50 isotones within the assumption of strong proton Z 28 and neutron N = 50 effective shell effects. (authors)

  6. A comparison of the survival (LD/sub 50/30/) of a number of inbred mouse strains after X and 60Co gamma irradiation

    International Nuclear Information System (INIS)

    Vacha, J.; Znojil, V.; Hola, J.; Sikulova, J.

    1984-01-01

    The value of LD/sub 50/30/ for X and 60 Co gamma radiation was ascertained for several inbred mouse strains and the significance of interstrain differences in these parameters determined. The rank order of strains according to LD/sub 50/30/ differs as between the two types of radiation with the exception of the strains BALB/c and B10.LP/Ph, which are the least resistant to radiation-induced lethality with both types of radiation. The strain C57BL/10ScSnPh is highly resistant to X irradiation. The relative biological effectiveness of 60 Co gamma radiation as compared with X-radiation from the point of view of lethality fluctuates between 0.748 and 0.952 in individual strains, with a mean value of 0.866 +- 0.033. The RBE values do not correlate with the radiosensitivity of the strain, but they do correlate with the relative contribution to erythropoiesis of the spleen. (author)

  7. Room temperature inverse magnetocaloric effect in Pd substituted Ni{sub 50}Mn{sub 37}Sn{sub 13} Heusler alloys

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Ritwik, E-mail: ritwik.saha@tifr.res.in; Nigam, A.K.

    2014-09-01

    The structural, magnetic and magnetocaloric effects for Ni{sub 50−x}Pd{sub x}Mn{sub 37}Sn{sub 13} Heusler alloys have been investigated around both structural and magnetic transitions. The room temperature X-ray diffraction indicates 10 M modulated martensitic structure with an orthorhombic unit cell for x=0 and 1. However, the superstructure reflections for x=2 alloy imply that the pattern is related to the L2{sub 1} phase. The maximum entropy change occurring at the martensitic transition is found to be 21 J kg{sup −1} K{sup −1} for Ni{sub 50}Mn{sub 37}Sn{sub 13} alloy around room temperature. Despite the smaller change in entropy around room temperature, 3.8 times larger value of refrigerant capacity (184.6 J/kg) is achieved for 2% substitution of Pd, due to occurrence of magnetic entropy change in a broader temperature region.

  8. Sub-50-as isolated extreme ultraviolet continua generated by 1.6-cycle near-infrared pulse combined with double optical gating scheme

    Science.gov (United States)

    Oguri, Katsuya; Mashiko, Hiroki; Ogawa, Tatsuya; Hanada, Yasutaka; Nakano, Hidetoshi; Gotoh, Hideki

    2018-04-01

    We demonstrate the generation of ultrabroad bandwidth attosecond continua extending to sub-50-as duration in the extreme ultraviolet (EUV) region based on a 1.6-cycle Ti:sapphire laser pulse. The combination of the amplitude gating scheme with a sub-two-cycle driver pulse and the double optical gating scheme achieves the continuum generation with a bandwidth of 70 eV at the full width at half maximum near the peak photon energy of 140 eV, which supports a Fourier-transform-limited pulse duration as short as 32 as. The carrier-envelope-phase (CEP) dependence of the attosecond continua shows a single-peak structure originating from the half-cycle cut-off at appropriate CEP values, which strongly indicates the generation of a single burst of an isolated attosecond pulse. Our approach suggests a possibility for isolated sub-50-as pulse generation in the EUV region by compensating for the intrinsic attosecond chirp with a Zr filter.

  9. Comparison of the survival (LD/sub 50/30/) of a number of inbred mouse strains after X and /sup 60/Co gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Vacha, J.; Znojil, V.; Hola, J.; Sikulova, J. (Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav)

    1984-01-01

    The value of LD/sub 50/30/ for X and /sup 60/Co gamma radiation was ascertained for several inbred mouse strains and the significance of interstrain differences in these parameters determined. The rank order of strains according to LD/sub 50/30/ differs as between the two types of radiation with the exception of the strains BALB/c and B10.LP/Ph, which are the least resistant to radiation-induced lethality with both types of radiation. The strain C57BL/10ScSnPh is highly resistant to X irradiation. The relative biological effectiveness of /sup 60/Co gamma radiation as compared with X-radiation from the point of view of lethality fluctuates between 0.748 and 0.952 in individual strains, with a mean value of 0.866 +- 0.033. The RBE values do not correlate with the radiosensitivity of the strain, but they do correlate with the relative contribution to erythropoiesis of the spleen.

  10. Probing the ground state and zero-field cooled exchange bias by magnetoresistance measurement in Mn{sub 50}Ni{sub 41}Sn{sub 9} ribbon

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jiyun [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); School of Materials Science and Engineering, China University of Mining & Technology, Xuzhou 221116 (China); Tu, Ruikang [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); School of Materials Science and Engineering, Soochow University, Suzhou 215000 (China); Fang, Xiaoting [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); Gu, Quanchao [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); School of Materials Science and Engineering, Soochow University, Suzhou 215000 (China); Zhou, Yanying [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); Cui, Rongjing [Department of Chemistry, Changshu Institute of Technology, Changshu 215500 (China); Han, Zhida, E-mail: han@cslg.edu.cn [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); Zhang, Lei; Fang, Yong [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); Qian, Bin, E-mail: njqb@cslg.edu.cn [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China); Zhang, Chengliang [School of Science, Jiangnan University, Wuxi 214122 (China); Jiang, Xuefan [Jiangsu Laboratory of Advanced Functional Materials, Department of Physics, Changshu Institute of Technology, Changshu 215500 (China)

    2017-03-15

    Recently, a new type of exchange bias (EB) after zero-field cooling has attracted considerable interest mainly in bulk magnetic competing systems. Here, we use a detailed magnetotransport investigation to probe the ground state and zero-field cooled EB (ZEB) in Mn{sub 50}Ni{sub 41}Sn{sub 9} ribbon. Both ZEB and field cooled EB were detected in magnetoresistance results consistent with magnetic measurement. A pure spin-glass ground state is proposed based on parabolic shape of low-field magnetoresistance combined with AC magnetization, memory effect. The appearance of ZEB is attributed to the field-induced nucleation and growth of ferromagnetic domains in the spin glass matrix forming unidirectional anisotropy at the interface. - Highlights: • Magnetoresistance was first used to probe the ground state and ZEB in Ni-Mn-based alloys. • A pure spin-glass ground state is proposed in Mn{sub 50}Ni{sub 41}Sn{sub 9} ribbon. • Field-induced nucleation and growth of ferromagnetic domains in SG results in ZEB.

  11. Microstructure, transformation behavior and mechanical properties of a (Ti{sub 50}Ni{sub 38}Cu{sub 12}){sub 93}Nb{sub 7} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Daqiang, E-mail: daqiang.jiang@uwa.edu.au [School of Mechanical and Chemical Engineering, The University of Western Australia (Australia); Department of Materials Science and Engineering, China University of Petroleum, Beijing (China); Liu, Yinong [School of Mechanical and Chemical Engineering, The University of Western Australia (Australia); Liu, Weilong; Song, Lixie; Jiang, Xiaohua [Department of Materials Science and Engineering, China University of Petroleum, Beijing (China); Yang, Hong [School of Mechanical and Chemical Engineering, The University of Western Australia (Australia); Cui, Lishan [Department of Materials Science and Engineering, China University of Petroleum, Beijing (China)

    2015-03-11

    A (Ti{sub 50}Ni{sub 38}Cu{sub 12}){sub 93}Nb{sub 7} alloy is fabricated by arc melting, forging and drawing. The microstructure, transformation behavior and mechanical properties were investigated by means of scanning electron microscope (SEM), differential scanning calorimeter (DSC), dynamic mechanical analyzer (DMA) and tensile test machine. SEM observation showed that the as cast alloy is composed of TiNiCu and Nb-rich phases. After drawing, the alloy showed single step transformations during heating and cooling within the whole annealing temperature range from 400 °C to 800 °C. With the increase of the annealing temperature, both the transformation temperatures and the damping capacity increased first and then decreased. The ultimate strength of the alloy after annealing at 400 °C is over 1500 MPa and the maximum elongation of the alloy after annealing at 800 °C is more than 20%.

  12. Animal mortality resulting from uniform exposures to photon radiations: Calculated LD/sub 50/s and a compilation of experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Jones, T.D.; Morris, M.D.; Wells, S.M.; Young, R.W.

    1986-12-01

    Studies conducted during the 1950s and 1960s of radiation-induced mortality to diverse animal species under various exposure protocols were compiled into a mortality data base. Some 24 variables were extracted and recomputed from each of the published studies, which were collected from a variety of available sources, primarily journal articles. Two features of this compilation effort are (1) an attempt to give an estimate of the uniform dose received by the bone marrow in each treatment so that interspecies differences due to body size were minimized and (2) a recomputation of the LD/sub 50/ where sufficient experimental data are available. Exposure rates varied in magnitude from about 10/sup -2/ to 10/sup 3/ R/min. This report describes the data base, the sources of data, and the data-handling techniques; presents a bibliography of studies compiled; and tabulates data from each study. 103 refs., 44 tabs.

  13. Observation of giant exchange bias in bulk Mn{sub 50}Ni{sub 42}Sn{sub 8} Heusler alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Jyoti; Suresh, K. G., E-mail: suresh@iitb.ac.in [Magnetic Materials Laboratory, Department of Physics, Indian institute of Technology Bombay, Mumbai, Maharashtra 400076 (India)

    2015-02-16

    We report a giant exchange bias (EB) field of 3520 Oe in bulk Mn{sub 50}Ni{sub 42}Sn{sub 8} Heusler alloy. The low temperature magnetic state of the martensite phase has been studied by DC magnetization and AC susceptibility measurements. Frequency dependence of spin freezing temperature (T{sub f}) on critical slowing down relation and observation of memory effect in zero field cooling mode confirms the super spin glass (SSG) phase at low temperatures. Large EB is attributed to the strong exchange coupling between the SSG clusters formed by small regions of ferromagnetic order embedded in an antiferromagnetic (AFM) matrix. The temperature and cooling field dependence of EB have been studied and related to the change in unidirectional anisotropy at SSG/AFM interface. The training effect also corroborates with the presence of frozen (SSG) moments at the interface and their role in EB.

  14. Exchange bias behavior in Ni{sub 50.0}Mn{sub 35.5} In{sub 14.5} ribbons annealed at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, T. [Dept. de Fisica, Universidad de Oviedo, Calvo Sotelo s/n, 33007 Oviedo (Spain); Sato Turtelli, R.; Groessinger, R. [Institut fur Festkoerperphysik, Technische Universitaet Wien, Wiedner Hauptstr. 8-10, 1040 Vienna (Austria); Sanchez, M.L.; Santos, J.D.; Rosa, W.O.; Prida, V.M. [Dept. de Fisica, Universidad de Oviedo, Calvo Sotelo s/n, 33007 Oviedo (Spain); Escoda, Ll.; Sunol, J.J. [Campus de Montilivi, Universidad de Girona, edifici PII, Lluis Santalo s/n. 17003 Girona (Spain); Koledov, V. [Kotelnikov Institute of Radio Engineering and Electronics, RAS, Moscow 125009 (Russian Federation); Hernando, B., E-mail: grande@uniovi.es [Dept. de Fisica, Universidad de Oviedo, Calvo Sotelo s/n, 33007 Oviedo (Spain)

    2012-10-15

    Heusler alloy Ni{sub 50.0}Mn{sub 35.5}In{sub 14.5} ribbons were prepared by melt-spinning technique. Several short time annealings were carried out in order to enhance the exchange bias effect in this alloy ribbon. The magnetic transition temperature increases with the annealing, compared to the as-spun sample, however no significant differences in respective Curie temperatures were observed for austenite and martensite phases in such annealed samples. Exchange bias effect is observed at low temperatures for all samples and practically vanishes at 60 K for the as-spun sample, whereas for the annealed ribbons it vanishes at 100 K.

  15. Suppression of the ferromagnetic order in the Heusler alloy Ni{sub 50}Mn{sub 35}In{sub 15} by hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Salazar Mejía, C., E-mail: Catalina.Salazar@cpfs.mpg.de; Mydeen, K.; Naumov, P.; Medvedev, S. A.; Wang, C.; Schwarz, U.; Felser, C.; Nicklas, M., E-mail: nicklas@cpfs.mpg.de [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden (Germany); Hanfland, M. [ESRF, BP220, 38043 Grenoble (France); Nayak, A. K. [Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden (Germany); Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany)

    2016-06-27

    We report on the effect of hydrostatic pressure on the magnetic and structural properties of the shape-memory Heusler alloy Ni{sub 50}Mn{sub 35}In{sub 15}. Magnetization and x-ray diffraction experiments were performed at hydrostatic pressures up to 5 GPa using diamond anvil cells. Pressure stabilizes the martensitic phase, shifting the martensitic transition to higher temperatures, and suppresses the ferromagnetic austenitic phase. Above 3 GPa, where the martensitic-transition temperature approaches the Curie temperature in the austenite, the magnetization shows no longer indications of ferromagnetic ordering. We further find an extended temperature region with a mixture of martensite and austenite phases, which directly relates to the magnetic properties.

  16. Study of crystallization kinetics and structural relaxation behavior in phase separated Ag{sub 33}Ge{sub 17}Se{sub 50} glassy alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Praveen, E-mail: prafiziks@gmail.com [Semiconductors Laboratory, Department of Physics, GND University, Amritsar 143005 (India); Nanotechnology Research Centre, DAV Institute of Engineering and Technology, Kabir Nagar, Jalandhar 144008 (India); Yannopoulos, S.N. [Foundation for Research and Technology Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes (FORTH/ICE-HT), P.O. Box 1414, GR-26 504, Rio-Patras (Greece); Sathiaraj, T.S. [Department of Physics, University of Botswana, Gaborone (Botswana); Thangaraj, R., E-mail: rthangaraj@rediffmail.com [Semiconductors Laboratory, Department of Physics, GND University, Amritsar 143005 (India)

    2012-07-16

    We report on the crystallization processes and structure (crystal phases) of Ag{sub 33}Ge{sub 17}Se{sub 50} glassy alloy using differential scanning calorimetry and x-ray diffraction techniques, respectively. The devitrification that gives rise to the first exothermic peak results in the crystallization of Ag{sub 2}Se and Ag{sub 8}GeSe{sub 6} phases, while the growth of GeSe{sub 2} accompanied by the transformation of Ag{sub 8}GeSe{sub 6} to Ag{sub 2}Se phase occurs during the second crystallization process. Different theoretical models are used to elucidate various kinetic parameters for the crystallization transformation process in this phase separated system. With annealing below the glass transition temperature, an inverse behavior between the variation of the optical gap and the band tailing parameter is observed for the thermally evaporated films. These results are explained as the mixing of different clusters/species in the amorphous state and/or changes caused by structural relaxation of the glassy network for the thermally evaporated films. - Highlights: Black-Right-Pointing-Pointer Phase separation in Ag{sub 33}Ge{sub 17}Se{sub 50} glassy alloy bordering two glass forming regions. Black-Right-Pointing-Pointer Transformation of Ag{sub 8}GeSe{sub 6} {yields} Ag{sub 2}Se along with crystallization GeSe{sub 2} phase. Black-Right-Pointing-Pointer Elucidation of various kinetic parameters for the crystalline transformation. Black-Right-Pointing-Pointer Structural relaxation in thermally evaporated films by optical spectroscopy.

  17. Magneto-structural transformations in Ni{sub 50}Mn{sub 37.5}Sn{sub 12.5−x}In{sub x} Heusler powders

    Energy Technology Data Exchange (ETDEWEB)

    Maziarz, Wojciech; Wójcik, Anna; Czaja, Paweł [Instituite of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta Str, 30-059 Kraków (Poland); Żywczak, Antoni [AGH University of Science and Technology, Academic Centre for Materials and Nanotechnology, Mickiewicza 30, 30-059 Kraków (Poland); Jan Dutkiewicz [Instituite of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta Str, 30-059 Kraków (Poland); Hawełek, Łukasz [Institute of Non-Ferrous Metals, ul. Sowinskiego 5, 44-100 Gliwice (Poland); Cesari, Eduard [Department de Física, Universitat de les Illes Balears, Ctra. de Valldemossa, km 7.5, Palma de Mallorca E-07122 (Spain)

    2016-08-15

    The effect of ball milling and subsequently annealing of melt spun ribbons on magneto-structural transformations in Ni{sub 50}Mn{sub 37.5}Sn{sub 12.5−x}In{sub x} (x=0, 2, 4, 6) ribbons is presented. Short time vibration milling allows to obtain chemically homogenous powders of angular particle shapes and size within 10–50 μm. Milling does not change the characteristic temperatures of martensitic transformation in comparison to the melt spun ribbons. The effect of In substitution for Sn on martensitic transformation has a complex mechanism, associated with electron density change. Substitution of Sn by In in both milled and annealed powders leads to decrease of Curie temperature of austenite and increase of martensitic transformation temperature, stabilizing martensitic phase. The coexistence of magnetic transformation of austenite and martensitic transformation at low magnetic field was observed. The intermartensitic transformation of 4O martensite to L1{sub 0} martensite was observed during cooling at low magnetic field and this was confirmed by TEM microstructure observations. The annealing process of as-milled powders leads to the change of their martensitic structure due to relaxation of internal stresses associated with anisotropic columnar grain microstructure formed during melt spinning process. The level of stresses introduced during milling of ribbons has no significant influence on martensitic transformation. The annealing process of as milled powders leads to enhancement of their magnetic properties, decrease of Curie temperature of austenite, and marginal change of temperature of martenisitic transformation. - Highlights: • Vibration milling of ribbons allows to obtain angular powders of size 10–50 μm. • Vibration milling improves chemical homogeneity of alloys. • Indium addition changes the magneto-structural transformations in Ni–Mn–Sn–In alloys. • Complex character of magneto-structural transformations is visible. • Multistep

  18. Calorimetric and magnetic study for Ni{sub 50}Mn{sub 36}In{sub 14} and relative cooling power in paramagnetic inverse magnetocaloric systems

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jing-Han, E-mail: jhchen@tamu.edu [Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); Bruno, Nickolaus M. [Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Karaman, Ibrahim [Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Huang, Yujin; Li, Jianguo [School of Materials Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Ross, Joseph H. [Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States)

    2014-11-28

    The non-stoichiometric Heusler alloy Ni{sub 50}Mn{sub 36}In{sub 14} undergoes a martensitic phase transformation in the vicinity of 345 K, with the high temperature austenite phase exhibiting paramagnetic rather than ferromagnetic behavior, as shown in similar alloys with lower-temperature transformations. Suitably prepared samples are shown to exhibit a sharp transformation, a relatively small thermal hysteresis, and a large field-induced entropy change. We analyzed the magnetocaloric behavior both through magnetization and direct field-dependent calorimetry measurements. For measurements passing through the first-order transformation, an improved method for heat-pulse relaxation calorimetry was designed. The results provide a firm basis for the analytic evaluation of field-induced entropy changes in related materials. An analysis of the relative cooling power (RCP), based on the integrated field-induced entropy change and magnetizing behavior of the Mn spin system with ferromagnetic correlations, shows that a significant RCP may be obtained in these materials by tuning the magnetic and structural transformation temperatures through minor compositional changes or local order changes.

  19. A sub-50meV spectrometer and energy filter for use in combination with 200kV monochromated (S)TEMs.

    Science.gov (United States)

    Brink, H A; Barfels, M M G; Burgner, R P; Edwards, B N

    2003-09-01

    A high-energy resolution post-column spectrometer for the purpose of electron energy loss spectroscopy (EELS) and energy-filtered TEM in combination with a monochromated (S)TEM is presented. The prism aberrations were corrected up to fourth order using multipole elements improving the electron optical energy resolution and increasing the acceptance of the spectrometer for a combination of object area and collection angles. Electronics supplying the prism, drift tube, high-tension reference and critical lenses have been newly designed such that, in combination with the new electron optics, a sub-50 meV energy resolution has been realized, a 10-fold improvement over past post-column spectrometer designs. The first system has been installed on a 200 kV monochromated TEM at the Delft University of Technology. Total system energy resolution of sub-100 meV has been demonstrated. For a 1s exposure the resolution degraded to 110 meV as a result of noise. No further degradation in energy resolution was measured for exposures up to 1 min at 120 kV. Spectral resolution measurements, performed on the pi* peak of the BN K-edge, demonstrated a 350 meV (FWHM) peak width at 200 kV. This measure is predominantly determined by the natural line width of the BN K-edge.

  20. Phase martensitic transformation study in mechanically alloyed Ti{sub 50}Ni{sub 25}Fe{sub 25} alloy via high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Joao Cardoso de; Ferreira, Ailton da Silva, E-mail: joao.cardoso.lima@ufsc.br [Universidade Federal de Santa Catarina (UFSC), Florianopolis (Brazil); Rovani, Pablo Roberto; Pereira, Altair Soria [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre (Brazil)

    2016-07-01

    Full text: Alloys based on titanium and nickel with shape memory effect (SME) have been widely investigated due to potential use in different areas of science and technology, such as electronics, medicine, and space.1 Among them, the superalloys Ti-Ni-Fe show high corrosion resistance and good mechanical properties even at high temperatures that make them suitable for use in applications such as power plant components that work under aggressive conditions. At room temperature, the TiNi alloy has a monoclinic (B19'), known as the martensitic phase. With increasing temperature, the B19' phase transforms into a trigonal/hexagonal (B19) phase, known as the R- or pre martensitic phase, which, in its turn, transforms into a cubic (B2) structure, known as the austenitic phase. On cooling to room temperature, the reverse B2→B19→B19' phase transformations are observed. Since the B19↔B19' transformation occurs at a temperature low enough to inhibit diffusion-controlled processes, it belongs to a class of diffusionless phase transformations known as martensitic transformations. For this study, a Ti{sub 50}Ni{sub 25}Fe{sub 25} (B2) alloy was prepared by mechanical alloying, and the effects of high pressures up to 18 GPa will be presented. The structural changes with increasing pressure were followed by recording in situ angle-dispersive X-ray diffraction (ADXRD) diffractograms, in transmission geometry, using a long fine focus Mo X-ray tube and an imaging plate detector. The obtained results were already reported in Ref [1]. (1) A. S. Ferreira, P. R. Rovani, J. C. de Lima, A. S. Pereira, J. Appl. Phys. 117 (2015). (author)

  1. LD/sub 50/ and selenium concentration in organs of rabbit following oral application of sodium selenite and toxicity verification of Ursoselevit-Praemix

    Energy Technology Data Exchange (ETDEWEB)

    Berschneider, F.; Hess, M.; Neuffer, K.; Willer, S.

    1976-07-01

    LC/sub 50/24 hr/ was established in the first of a series of experiments on 72 rabbits for orally applied sodium selenite. The dosage was 8.62 mg/kg live weight, the confidence interval being (1 - ..cap alpha.. = 0.95) +/- 0.13 mg/kg. The value was four times as high following intravenous application. Complete lethality was recorded from 15 mg Na/sub 2/SeO/sub 3//kg live weight within 21 hours. Thirty-six animals were involved in the second experiment of the series. They had 50 or 100 percent Ursoselevit-Praemix (30 ppm Se) in their rations. Body mass development of the test animals was superior to that recorded from the controls in the first 50 days, after which limit the former declined strongly in a few days. Their general condition worsened. Postmortem finding, following slaughter, included catarrhal enteritis, toxic liver dystrophy, scattered pulpous tumors in the spleen, and interstitial nephritis. In the third experiment (50 percent Ursoselevit-Praemix with 60 ppm Se in the rations), the test animals developed better than the controls during the first two months, after which point they exhibited the same clinical symptoms as those observed in the second experiment, stopped putting on weight, and eventually turned cachectic. The pathomorphological findings were identical with those obtained from the second experiment. The selenium concentrations in the organs of the test animals all were much higher than those of the controls. Their amounts in excess to base values were up to eleven times in the blood, nine times in the liver, twelve times in the kidneys, and 13 times in the muscles. 11 references, 2 figures, 2 tables.

  2. Rapid solidification of Ni{sub 50}Nb{sub 28}Zr{sub 22} glass former alloy through suction-casting; Solidificacao rapida da liga formadora de fase amorfa Ni{sub 50}Nb{sub 28}Zr{sub 22} atraves de fundicao em coquilha por succao

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, M.I.; Santos, F.S.; Bolfarini, C.; Botta Filho, W.J.; Kiminami, C.S., E-mail: issao16@gmail.co [Universidade Federal de Sao Carlos (DEMa/UFSCar), SP (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    To select new alloys with high glass forming ability (GFA) to present amorphous structure in millimeter scale, several semi-empirical models have been developed. In the present work, a new alloy, Ni{sub 50}Nb{sub 28}Zr{sub 22}d, was designed based on the combination of topological instability lambda (A) criterion and electronegativity difference ({Delta}e). The alloy was rapidly solidified in a bulk wedge sample by cooper mold suction casting in order to investigate its amorphization. The sample was characterized by the combination of scanning electron microscopy (MEV), X-ray diffraction (XRD) and differential scanning calorimeter (DSC). For the minimum thickness of 200 {mu}m analyzed, it was found that the alloy did not show a totally amorphous structure. Factor such as low cooling rate, existence of oxides on the surface of the elements and presence of oxygen in the atmosphere of equipment did not allowed the achievement of higher amorphous thickness. (author)

  3. Ternary scandium-rich indides Sc{sub 50}T{sub 13}In{sub 3} and Sc{sub 50}Rh{sub 13}In{sub 3}O{sub y} (T = Rh, Ir; y {approx} 8) - synthesis and crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Zaremba, R.; Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Univ. Muenster (Germany)

    2007-12-15

    New intermetallic compounds Sc{sub 50}Rh{sub 13.3}In{sub 2.7} and Sc{sub 50}Ir{sub 13.6}In{sub 2.4} and the suboxides Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8} and Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0} were synthesized from the elements or with Sc{sub 2}O{sub 3} as an oxygen source, respectively, in sealed tantalum tubes in a water-cooled sample chamber of an induction furnace. They crystallize with a new cubic structure type, space group F m anti 3, a = 1772.5(6) pm, wR2 = 0.032, 1111 F{sup 2} values, 34 variables for Sc{sub 50}Rh{sub 13.3}In{sub 2.7}, a = 1766.5(6) pm, wR2 = 0.041, 745 F{sup 2} values, 34 variables for Sc{sub 50}Ir{sub 13.6}In{sub 2.4}, a = 1764.4(2) pm, wR2 = 0.044, 640 F{sup 2} values, 41 variables for Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8}, and a = 1761.5(6) pm, wR2 = 0.054, 740 F{sup 2} values, 42 variables for Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0}. The main structural motifs are rhodium-centered indium cubes in an fcc like arrangement in which the octahedral and tetrahedral voids are filled by In2Sc{sub 12} and In1Sc{sub 12} icosahedra, respectively, resembling a Li{sub 3}Bi-like structure. The Rh1 (Ir1) and Sc4 atoms lie between these polyhedral units. The oxygen atoms partially fill Sc{sub 6} octahedra in Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8} and Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0} with Sc-O distances of 214 - 230 pm. These octahedra are condensed via common edges and faces, encapsulating the In2Sc{sub 12} icosahedra. Due to the high scandium content one observes strong Sc-Sc bonding with Sc-Sc distances ranging from 303 to 362 pm in Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8}. The shortest distances occur for Sc-Rh (267 - 295 pm). The crystal chemical relationship with the Li{sub 3}Bi-related suboxide Ti{sub 12}Sn{sub 3}O{sub 10} is discussed. (orig.)

  4. Crystal structure, magnetization, {sup 125}Te NMR, and Seebeck coefficient of Ge{sub 49}Te{sub 50}R{sub 1} (R = La, Pr, Gd, Dy, and Yb)

    Energy Technology Data Exchange (ETDEWEB)

    Levin, E.M., E-mail: levin@iastate.edu [Division of Materials Sciences and Engineering, US Department of Energy Ames Laboratory, Ames, IA 50011 (United States); Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Cooling, C. [Division of Materials Sciences and Engineering, US Department of Energy Ames Laboratory, Ames, IA 50011 (United States); Bud’ko, S.L. [Division of Materials Sciences and Engineering, US Department of Energy Ames Laboratory, Ames, IA 50011 (United States); Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Straszheim, W.E. [Division of Materials Sciences and Engineering, US Department of Energy Ames Laboratory, Ames, IA 50011 (United States); Lograsso, T.A. [Division of Materials Sciences and Engineering, US Department of Energy Ames Laboratory, Ames, IA 50011 (United States); Department of Materials Sciences and Engineering, Iowa State University, Ames, IA 50011 (United States)

    2017-05-01

    GeTe, a self-doping semiconductor, is a well-known base compound for thermoelectric and phase-change materials. It is known, that replacement of Ge in Ag{sub 6.5}Sb{sub 6.5}Ge{sub 37}Te{sub 50} (TAGS-85) material by rare earth Dy significantly enhances both the power factor and thermoelectric figure of merit. Here we demonstrate how replacement of Ge in GeTe by rare earths with different atomic size and localized magnetic moments affect XRD patterns, magnetization, {sup 125}Te NMR spectra and spin-lattice relaxation, and the Seebeck coefficient of the alloys with a nominal composition of Ge{sub 49}Te{sub 50}R{sub 1} (R = La, Pr, Gd, Dy, and Yb). SEM, EDS and WDS data show that rare earth atoms in the matrix are present at smaller extent compared to a nominal composition, whereas rare earth also is present in inclusions. Rare earths affect the Seebeck coefficient, which is a result of interplay between the reduction due to higher carrier concentration and enhancement due to magnetic contribution. The effect of replacement of Ge in GeTe by Dy on the Seebeck coefficient is smaller than that observed in Ag{sub 6.5}Sb{sub 6.5}Ge{sub 36} Te{sub 50}Dy{sub 1}. This can be explained by larger amount of rare earth, which can be embedded into the lattice of materials containing [Ag + Sb] atomic pairs and possible effect from these pairs. - Highlights: • The effects of rare earth in Ge{sub 49}Te{sub 50}R{sub 1} (R = La, Pr, Gd, Dy, and Yb) are studied. • Rare earth atoms in the matrix are present at smaller extent compared to a nominal composition. • The effect on the Seebeck coefficient is a result from carrier concentration and magnetic contribution.

  5. Role of nano-precipitation on the microstructure and shape memory characteristics of a new Ni{sub 50.3}Ti{sub 34.7}Zr{sub 15} shape memory alloy

    Energy Technology Data Exchange (ETDEWEB)

    Evirgen, A. [Department of Materials Science and Engineering, Texas A& M University, College Station, TX 77843 (United States); Karaman, I., E-mail: ikaraman@tamu.edu [Department of Materials Science and Engineering, Texas A& M University, College Station, TX 77843 (United States); Pons, J.; Santamarta, R. [Departament de Fisica, Universitat de les Illes Balears, E07122 Palma de Mallorca (Spain); Noebe, R.D. [Materials and Structures Division, NASA Glenn Research Center, Cleveland, OH 44135 (United States)

    2016-02-08

    The microstructure and shape memory characteristics of the Ni{sub 50.3}Ti{sub 34.7}Zr{sub 15} shape memory alloy were investigated as a function of aging heat treatments that result in nanometer to submicron size precipitates. Microstructure–property relationships were developed by characterizing samples using transmission electron microscopy, differential scanning calorimetry, and load-biased thermal cycling experiments. The precipitate size was found to strongly influence the martensitic transformation–precipitate interactions and ultimately the shape memory characteristics of the alloy. Aging treatments resulting in relatively fine precipitates, which are not an obstacle to twin boundaries and easily bypassed by martensite variants, exhibited higher transformation strain, lower transformation thermal hysteresis, and better thermal and dimensional stability compared to samples with relatively large precipitates. When precipitate dimensions approached several hundred nanometers in size they acted as obstacles to martensite growth, limiting martensite variant and twin size resulting in reduced functional and structural properties. Aging heat treatments were also shown to result in a wide range of transformation temperatures, increasing them above 100 °C in some cases, and affected the stress dependence of the transformation hysteresis and the stress versus transformation temperature relationships for the Ni{sub 50.3}Ti{sub 34.7}Zr{sub 15} alloy.

  6. Investigation of multifunctional properties of Mn{sub 50}Ni{sub 40−x}Co{sub x}Sn{sub 10} (x = 0–6) Heusler alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Jyoti; Suresh, K.G., E-mail: suresh@phy.iitb.ac.in

    2015-01-25

    Highlights: • Mn{sub 50}Ni{sub 40−x}Co{sub x}Sn{sub 10} Heusler alloys exhibit multifunctional properties. • Co doping results decrease in martensitic transition temperature and increase in T{sub C}{sup A}. • Ferromagnetic coupling increases with increase in Co concentration. • Large positive ΔS{sub M} of 10.5 J/kg K and large RCP of 125 J/kg was obtained for x = 1. • Large exchange bias field of 833 Oe was observed for Mn{sub 50}Ni{sub 39}Co{sub 1}Sn{sub 10} alloy. - Abstract: A series of Co doped Mn{sub 50}Ni{sub 40−x}Co{sub x}Sn{sub 10} (x = 0, 1, 2, 2.5, 3, 4 and 6) Heusler alloys has been investigated for their structural, magnetic, magnetocaloric and exchange bias properties. The martensitic transition temperatures are found to decrease with the increase in Co concentration due to the decrease in valence electron concentration (e/a ratio). The Curie temperature of austenite phase increases significantly with increasing Co concentration. A large positive magnetic entropy change (ΔS{sub M}) of 8.6 and 10.5 J/kg K, for a magnetic field change of 50 kOe is observed for x = 0 and 1 alloys, and ΔS{sub M} values decreases for higher Co concentrations. The relative cooling power shows a monotonic increase with the increase in Co concentration. Large exchange bias fields of 920 Oe and 833 Oe have been observed in the alloys with compositions x = 0 and 1, after field cooling in presence of 10 kOe. The unidirectional anisotropy arising at the interface between the frustrated and ferromagnetic phases is responsible for the large exchange bias observed in these alloys. With increase in Co, the magnetically frustrated phase diminishes in strength, giving rise to a decrease in the exchange bias effect for larger Co concentration. The exchange bias fields observed for compositions x = 0 and 1, in the present case are larger than that reported for Co doped Ni–Mn–Z (Z = Sn, Sb, and Ga) alloys. Temperature and cooling field dependence of the exchange bias

  7. Surface functionalized hollow silica particles and composites

    KAUST Repository

    Rodionov, Valentin; Khanh, Vu Bao

    2017-01-01

    Composition comprising hollow spherical silica particles having outside particle walls and inside particle walls, wherein the particles have an average particle size of about 10 nm to about 500 nm and an average wall thickness of about 10 nm to about 50 nm; and wherein the particles are functionalized with at least one organic functional group on the outside particle wall, on the inside particle wall, or on both the outside and inside particle walls, wherein the organic functional group is in a reacted or unreacted form. The organic functional group can be epoxy. The particles can be mixed with polymer precursor or a polymer material such as epoxy to form a prepreg or a nanocomposite. Lightweight but strong materials can be formed. Low loadings of hollow particles can be used.

  8. Surface functionalized hollow silica particles and composites

    KAUST Repository

    Rodionov, Valentin

    2017-05-26

    Composition comprising hollow spherical silica particles having outside particle walls and inside particle walls, wherein the particles have an average particle size of about 10 nm to about 500 nm and an average wall thickness of about 10 nm to about 50 nm; and wherein the particles are functionalized with at least one organic functional group on the outside particle wall, on the inside particle wall, or on both the outside and inside particle walls, wherein the organic functional group is in a reacted or unreacted form. The organic functional group can be epoxy. The particles can be mixed with polymer precursor or a polymer material such as epoxy to form a prepreg or a nanocomposite. Lightweight but strong materials can be formed. Low loadings of hollow particles can be used.

  9. Effective particle magnetic moment of multi-core particles

    International Nuclear Information System (INIS)

    Ahrentorp, Fredrik; Astalan, Andrea; Blomgren, Jakob; Jonasson, Christian; Wetterskog, Erik; Svedlindh, Peter; Lak, Aidin; Ludwig, Frank; IJzendoorn, Leo J. van; Westphal, Fritz; Grüttner, Cordula; Gehrke, Nicole; Gustafsson, Stefan; Olsson, Eva; Johansson, Christer

    2015-01-01

    In this study we investigate the magnetic behavior of magnetic multi-core particles and the differences in the magnetic properties of multi-core and single-core nanoparticles and correlate the results with the nanostructure of the different particles as determined from transmission electron microscopy (TEM). We also investigate how the effective particle magnetic moment is coupled to the individual moments of the single-domain nanocrystals by using different measurement techniques: DC magnetometry, AC susceptometry, dynamic light scattering and TEM. We have studied two magnetic multi-core particle systems – BNF Starch from Micromod with a median particle diameter of 100 nm and FeraSpin R from nanoPET with a median particle diameter of 70 nm – and one single-core particle system – SHP25 from Ocean NanoTech with a median particle core diameter of 25 nm

  10. Effective particle magnetic moment of multi-core particles

    Science.gov (United States)

    Ahrentorp, Fredrik; Astalan, Andrea; Blomgren, Jakob; Jonasson, Christian; Wetterskog, Erik; Svedlindh, Peter; Lak, Aidin; Ludwig, Frank; van IJzendoorn, Leo J.; Westphal, Fritz; Grüttner, Cordula; Gehrke, Nicole; Gustafsson, Stefan; Olsson, Eva; Johansson, Christer

    2015-04-01

    In this study we investigate the magnetic behavior of magnetic multi-core particles and the differences in the magnetic properties of multi-core and single-core nanoparticles and correlate the results with the nanostructure of the different particles as determined from transmission electron microscopy (TEM). We also investigate how the effective particle magnetic moment is coupled to the individual moments of the single-domain nanocrystals by using different measurement techniques: DC magnetometry, AC susceptometry, dynamic light scattering and TEM. We have studied two magnetic multi-core particle systems - BNF Starch from Micromod with a median particle diameter of 100 nm and FeraSpin R from nanoPET with a median particle diameter of 70 nm - and one single-core particle system - SHP25 from Ocean NanoTech with a median particle core diameter of 25 nm.

  11. Effective particle magnetic moment of multi-core particles

    Energy Technology Data Exchange (ETDEWEB)

    Ahrentorp, Fredrik; Astalan, Andrea; Blomgren, Jakob; Jonasson, Christian [Acreo Swedish ICT AB, Arvid Hedvalls backe 4, SE-411 33 Göteborg (Sweden); Wetterskog, Erik; Svedlindh, Peter [Department of Engineering Sciences, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden); Lak, Aidin; Ludwig, Frank [Institute of Electrical Measurement and Fundamental Electrical Engineering, TU Braunschweig, D‐38106 Braunschweig Germany (Germany); IJzendoorn, Leo J. van [Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Westphal, Fritz; Grüttner, Cordula [Micromod Partikeltechnologie GmbH, D ‐18119 Rostock (Germany); Gehrke, Nicole [nanoPET Pharma GmbH, D ‐10115 Berlin Germany (Germany); Gustafsson, Stefan; Olsson, Eva [Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg (Sweden); Johansson, Christer, E-mail: christer.johansson@acreo.se [Acreo Swedish ICT AB, Arvid Hedvalls backe 4, SE-411 33 Göteborg (Sweden)

    2015-04-15

    In this study we investigate the magnetic behavior of magnetic multi-core particles and the differences in the magnetic properties of multi-core and single-core nanoparticles and correlate the results with the nanostructure of the different particles as determined from transmission electron microscopy (TEM). We also investigate how the effective particle magnetic moment is coupled to the individual moments of the single-domain nanocrystals by using different measurement techniques: DC magnetometry, AC susceptometry, dynamic light scattering and TEM. We have studied two magnetic multi-core particle systems – BNF Starch from Micromod with a median particle diameter of 100 nm and FeraSpin R from nanoPET with a median particle diameter of 70 nm – and one single-core particle system – SHP25 from Ocean NanoTech with a median particle core diameter of 25 nm.

  12. Synthesis and properties of unagglomerated nanocomposite particles for nanomedical applications

    Science.gov (United States)

    Rouse, Sarah M.

    2005-11-01

    Methods have been developed to prepare stable, unagglomerated active-medical-agent nanoparticles in a range of sizes, based on reverse-micelle microemulsion techniques. The process used to prepare monodisperse, spherical nanocomposite particles is based on methods originally outlined in detail by Adair et al. and Li et al. The "Molecular Dot" (MD) nanoparticles incorporate a variety of medically-active substances, such as organic fluorophores and therapeutic drugs, internally distributed in silica, titania, calcium phosphate, or calcium phospho-silicate matrices. The synthesis techniques have also been modified to produce nanoparticles containing combinations of fluorophores and medicinal agents, in order to monitor drug release and location. The specific biomedical application for the nanocomposite particles dictates the selection of core and shell-matrix materials. For example, the protective shell-matrices of the silica and titania MDs shield the active-medical agents from damage due to changes in pH, temperature, and other environmental effects. Conversely, the calcium phosphate and calcium phospho-silicate shell-matrix nanoparticles can potentially be engineered to dissolve in physiological environments. The method used to remove residual precursor materials while maintaining a well-dispersed assembly of nanoparticles is critical to the use of nanocolloids in medical applications. The dispersion approach is based on protection-dispersion theory tailored to accommodate the high surface areas and reactivity of sub-50 nm particles in aqueous or water/ethanol mixtures. Dispersion of the nanocomposite particles is further enhanced with the use of size-exclusion high performance liquid chromatography (HPLC) to simultaneously wash and disperse the nanocomposite particle suspensions. The state of dispersion of the nanosuspensions is evaluated using the average agglomeration number (AAN) approach in conjunction with other characterization techniques. The formulation of

  13. Toward Rapid Unattended X-ray Tomography of Large Planar Samples at 50-nm Resolution

    International Nuclear Information System (INIS)

    Rudati, J.; Tkachuk, A.; Gelb, J.; Hsu, G.; Feng, Y.; Pastrick, R.; Lyon, A.; Trapp, D.; Beetz, T.; Chen, S.; Hornberger, B.; Seshadri, S.; Kamath, S.; Zeng, X.; Feser, M.; Yun, W.; Pianetta, P.; Andrews, J.; Brennan, S.; Chu, Y. S.

    2009-01-01

    X-ray tomography at sub-50 nm resolution of small areas (∼15 μmx15 μm) are routinely performed with both laboratory and synchrotron sources. Optics and detectors for laboratory systems have been optimized to approach the theoretical efficiency limit. Limited by the availability of relatively low-brightness laboratory X-ray sources, exposure times for 3-D data sets at 50 nm resolution are still many hours up to a full day. However, for bright synchrotron sources, the use of these optimized imaging systems results in extremely short exposure times, approaching live-camera speeds at the Advanced Photon Source at Argonne National Laboratory near Chicago in the US These speeds make it possible to acquire a full tomographic dataset at 50 nm resolution in less than a minute of true X-ray exposure time. However, limits in the control and positioning system lead to large overhead that results in typical exposure times of ∼15 min currently.We present our work on the reduction and elimination of system overhead and toward complete automation of the data acquisition process. The enhancements underway are primarily to boost the scanning rate, sample positioning speed, and illumination homogeneity to performance levels necessary for unattended tomography of large areas (many mm 2 in size). We present first results on this ongoing project.

  14. Scalability of Ferroelectric Tunnel Junctions to Sub-100 nm Dimensions

    Science.gov (United States)

    Abuwasib, Mohammad

    The ferroelectric tunnel junction (FTJ) is an emerging low-power device that has potential application as a non-volatile memory and logic element in beyond-CMOS circuits. As a beyond- CMOS device, it is necessary to investigate the device scaling limit of FTJs to sub-50 nm dimensions. In addition to the fabrication of scaled FTJs, the integration challenges and CMOS compatibility of the device needs to be addressed. FTJ device performance including ON/OFF ratio, memory retention time, switching endurance, write /read speed and power dissipation need to be characterized for benchmarking of this emerging device, compared to its charge-based counterparts such as DRAM, NAND/NOR flash, as well as to other emerging memory devices. In this dissertation, a detailed investigation of scaling of BaTiO3 (BTO) based FTJs was performed, from full-scale integration to electrical characterization. Two types of FTJs with La0.67Sr0.33MnO3 (LSMO) and SrRuO3 (SRO) bottom electrodes were investigated in this work namely; Co/BTO/LSMO and Co/BTO/SRO. A CMOS compatible fabrication process for integration of Co/BTO/LSMO FTJ devices ( 3x3 microm 2) was demonstrated for the first time using standard photolithography and self-aligned RIE technique. The fabricated FTJ device showed switching behavior, however, degradation of the LSMO contact was observed during the fabrication process. A detailed investigation of the contact properties of bottom electrode materials (LSMO, SRO) for BTO-based FTJs was performed. The process and thermal stability of different contact overlayers (Ti, Pt) was explained to understand the nature of the ohmic contacts for metal to SRO and LSMO layers. Noble metals-to-SRO was found to form the most stable contacts for FTJs. Based on this study, a systematic scalability study of Co/BTO/SRO FTJs was carried out from micron ( 3x3 microm2) to submicron ( 200x200 nm2) dimensions. Positive UP Negative Down (PUND) measurement confirms the ferroelectric properties of the BTO

  15. Effect of Al doping on structural and magnetic properties of Ni{sub 50}Mn{sub 37}Al{sub x}Sb{sub 13−x} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Mayukh K.; Bagani, K. [Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Singh, R.K.; Majumdar, B. [Defense Metrological Research Laboratory, Hyderabad 500058 (India); Banerjee, S., E-mail: sangam.banerjee@saha.ac.in [Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India)

    2014-09-01

    The Ni{sub 50}Mn{sub 37}Al{sub x}Sb{sub 13−x} (x=0, 1, 3 and 5) alloys were prepared by tri-arc melting technique. The replacement of Sb by Al increases the martensitic transformation temperature (T{sub M}) as well as ferromagnetic to paramagnetic transformation temperature (T{sub C}{sup A}) within the austenite phase. The increase in T{sub M} is found to due to the enhancement of hybridization between 3d states of Ni and Mn atoms. We also observed a large exchange bias field (H{sub EB}) of 470 Oe for x=0 and it decreases with the Al concentration for field cooled (FC) magnetic hysteresis loop. A large magnetic entropy change (ΔS{sub M}) of 10 J/kg-K is found for x=1 alloy under a field change (ΔH) of 50 kOe and it decreased for further higher concentration of Al doping. The possible reasons for observed behaviors are discussed.

  16. Megasonic cleaning strategy for sub-10nm photomasks

    Science.gov (United States)

    Hsu, Jyh-Wei; Samayoa, Martin; Dress, Peter; Dietze, Uwe; Ma, Ai-Jay; Lin, Chia-Shih; Lai, Rick; Chang, Peter; Tuo, Laurent

    2016-10-01

    One of the main challenges in photomask cleaning is balancing particle removal efficiency (PRE) with pattern damage control. To overcome this challenge, a high frequency megasonic cleaning strategy is implemented. Apart from megasonic frequency and power, photomask surface conditioning also influences cleaning performance. With improved wettability, cleanliness is enhanced while pattern damage risk is simultaneously reduced. Therefore, a particle removal process based on higher megasonic frequencies, combined with proper surface pre-treatment, provides improved cleanliness without the unintended side effects of pattern damage, thus supporting the extension of megasonic cleaning technology into 10nm half pitch (hp) device node and beyond.

  17. 8 nm nanodiamonds as markers for 2 photon excited luminescent microscopy

    International Nuclear Information System (INIS)

    Kharin, A; Rogov, A; Bonacina, L; Geloen, A; Lysenko, V

    2016-01-01

    Structural and luminescent properties of stable suspensions of fluorescent nanodiamonds were investigated. Measurement of the effective hydrodynamic radius yields particles less than 30 nm diameter, while the TEM measurements made on the same particles shows average diameter about 8 nm. It was found that NDs have relatively low toxicity. Upon incubation, 3T3-L1 cells spontaneously take up nanodiamonds that uniformly distribute in cells cytoplasm. The possibility of fluorescent imaging using both single ore two-photon excitation was shown. (paper)

  18. 355-nm hypersensitization of optical fibers

    NARCIS (Netherlands)

    Canagasabey, A.; Canning, J.; Groothoff, N.

    2003-01-01

    A study is presented on 355-nm hypersensitization of optical fibers. It is found that the intrinsic 244-nm photosensitivity of boron-codoped germanosilicate optical fibers is enhanced by 355-nm hypersensitization. Hypersensitization through standard polymer coating is also demonstrated.

  19. Mechanistic comparison of pulse laser induced phase separation of particulates from cellulose paper at 213 nm and 532 nm

    Energy Technology Data Exchange (ETDEWEB)

    Arif, S.; Forster, M.; Kautek, W. [University of Vienna, Department of Physical Chemistry, Wien (Austria); Bushuk, S.; Kouzmouk, A.; Tatur, H.; Batishche, S. [National Academy of Sciences of the Republic of Belarus, Institute of Physics, Minsk (Belarus)

    2013-02-15

    The laser-induced phase separation of charcoal particles on additive-free cotton linters cellulose paper was investigated by electron and optical microscopy, colorimetry, and diffuse reflectance FT-IR. The fibre bundles were vaporised in depth of several 10 {mu}m above destruction fluence thresholds using visible 532 nm radiation. This is in contrast to mid-ultraviolet 213 nm radiation, where only the top fibre bundles were modified and partially evaporated. The colorimetric lightness results generally represented the cleaning status, whereas the colorimetric yellowing data represented irreversible chemical and/or photochemical changes. Charcoal-contaminated paper treated with visible and mid-ultraviolet radiation exhibited yellowing, whereas uncontaminated did not. This suggests that the electron-rich plasma generated by the evaporation of the particles heats the adjacent substrate and also excludes oxygen. Mid-ultraviolet, in contrast to visible radiation, shows particle removal always accompanied by paper destruction. IR spectroscopy results suggest cross-linking by ether bonds near the destruction threshold, but do not prove the formation of oxidation products and double bonds as the basis of the yellowing. A ''cleaning window'' between the cleaning threshold (0.1 J/cm{sup 2}) and the paper destruction threshold (2.9 J/cm{sup 2}) with a pulse number of 2 is provided by visible 532 nm laser treatment. (orig.)

  20. Mechanistic comparison of pulse laser induced phase separation of particulates from cellulose paper at 213 nm and 532 nm

    International Nuclear Information System (INIS)

    Arif, S.; Forster, M.; Kautek, W.; Bushuk, S.; Kouzmouk, A.; Tatur, H.; Batishche, S.

    2013-01-01

    The laser-induced phase separation of charcoal particles on additive-free cotton linters cellulose paper was investigated by electron and optical microscopy, colorimetry, and diffuse reflectance FT-IR. The fibre bundles were vaporised in depth of several 10 μm above destruction fluence thresholds using visible 532 nm radiation. This is in contrast to mid-ultraviolet 213 nm radiation, where only the top fibre bundles were modified and partially evaporated. The colorimetric lightness results generally represented the cleaning status, whereas the colorimetric yellowing data represented irreversible chemical and/or photochemical changes. Charcoal-contaminated paper treated with visible and mid-ultraviolet radiation exhibited yellowing, whereas uncontaminated did not. This suggests that the electron-rich plasma generated by the evaporation of the particles heats the adjacent substrate and also excludes oxygen. Mid-ultraviolet, in contrast to visible radiation, shows particle removal always accompanied by paper destruction. IR spectroscopy results suggest cross-linking by ether bonds near the destruction threshold, but do not prove the formation of oxidation products and double bonds as the basis of the yellowing. A ''cleaning window'' between the cleaning threshold (0.1 J/cm 2 ) and the paper destruction threshold (2.9 J/cm 2 ) with a pulse number of 2 is provided by visible 532 nm laser treatment. (orig.)

  1. Electrodeposition of nickel particles and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, G. T. [Centro de Investigacion en Quimica Aplicada, Laboratorio de Microscopia. Blvd. Enrique Reyna No. 140, Saltillo 25253, Coahuila (Mexico); Zavala, G.; Videa, M. [ITESM, Campus Monterrey, Depto. de Fisica, Av. Garza Sada 2501 Sur, Monterrey 64849, N. L. (Mexico)], e-mail: gtadeo@ciqa.mx

    2009-07-01

    Electrodeposition of nickel particles on ITO substrates is achieved by current pulse reduction. A comparison between potential pulse and current pulse experiments presents differences in particle size and particle size distribution. The latter shows smaller particle size dispersion than what is found with potential pulses. Characterization of the particles carried out by Atomic Force Microscopy shows particles with average sizes between 100 to 300 nm. Magnetic characterization by Magnetic Force Microscopy and SQUID shows that particles of {approx} 300 nm were ferromagnetic with a coercive field of 200 Oe and a saturation magnetization of 40 x 10{sup -6} emu at 300 K. (Author)

  2. Magnetocaloric properties of as-quenched Ni{sub 50.4}Mn{sub 34.9}In{sub 14.7} ferromagnetic shape memory alloy ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Llamazares, J.L. [Instituto Potosino de Investigacion Cientifica y Tecnologica (IPICYT), San Luis Potosi, S.L.P. (Mexico); Garcia, C. [MIT, Department of Materials Science and Engineering, Massachusetts (United States); Hernando, B.; Prida, V.M. [Universidad de Oviedo, Departamento de Fisica, Facultad de Ciencias, Oviedo (Spain); Baldomir, D.; Serantes, D. [Universidade de Santiago de Compostela, Departamento de Fisica Aplicada, Facultad de Fisica, Santiago de Compostela (Spain); Gonzalez, J. [UPV, Departamento Fisica de Materiales, Facultad de Quimica, San Sebastian (Spain)

    2011-06-15

    The temperature dependences of magnetic entropy change and refrigerant capacity have been calculated for a maximum field change of {delta} H=30 kOe in as-quenched ribbons of the ferromagnetic shape memory alloy Ni{sub 50.4}Mn{sub 34.9}In{sub 14.7} around the structural reverse martensitic transformation and magnetic transition of austenite. The ribbons crystallize into a single-phase austenite with the L2{sub 1}-type crystal structure and Curie point of 284 K. At 262 K austenite starts its transformation into a 10-layered structurally modulated monoclinic martensite. The first- and second-order character of the structural and magnetic transitions was confirmed by the Arrott plot method. Despite the superior absolute value of the maximum magnetic entropy change obtained in the temperature interval where the reverse martensitic transformation occurs ({delta}S{sub M} {sup max}=7.2 Jkg{sup -1}K{sup -1}) with respect to that obtained around the ferromagnetic transition of austenite ({delta} S{sub M} {sup max}=2.6 Jkg{sup -1}K{sup -1}), the large average hysteretic losses due to the effect of the magnetic field on the phase transformation as well as the narrow thermal dependence of the magnetic entropy change make the temperature interval around the ferromagnetic transition of austenite of a higher effective refrigerant capacity (RC{sup magn}{sub eff}=95Jkg{sup -1} versus RC{sup struct}{sub eff}=60Jkg{sup -1}). (orig.)

  3. Particle Pollution

    Science.gov (United States)

    ... Your Health Particle Pollution Public Health Issues Particle Pollution Recommend on Facebook Tweet Share Compartir Particle pollution — ... see them in the air. Where does particle pollution come from? Particle pollution can come from two ...

  4. Characteristics of Charging and Collection of 10-nm-Class Ultrafine Nanoparticles in an Electrostatic Precipitator

    International Nuclear Information System (INIS)

    Han, Bang Woo; Kim, Hak Joon; Kim, Yong Jin; Song, Dong Keun; Hong, Won Seok; Shin, Wan Ho

    2011-01-01

    The charging of 10-nm-class nanoparticles in an electrostatic precipitator (ESP) according to particle charging ratio has been investigated and compared to the diffusion effect of the nanoparticles. The competition between the charging probability and the diffusion loss effect determines the collection efficiency of nanoparticles in the ESP. The collection efficiency of nanoparticles decreased continuously with decreasing particle diameter. This indicates that the partial charging effect of 10-nm-class nanoparticles is more dominant than their diffusion loss effect in the ESP for nanoparticles in the particle size range of less than 10 nm. The charging ratios based on unipolar diffusion charging calculations were in good agreement with the experimental collection efficiencies for nanoparticles less than 10 nm in diameter

  5. Advances in 750 nm VECSELs (Conference Presentation)

    Science.gov (United States)

    Saarinen, Esa J.; Ranta, Sanna; Lyytikäinen, Jari; Saarela, Antti; Sirbu, Alexei; Iakovlev, Vladimir; Kapon, Eli; Guina, Mircea

    2017-03-01

    Lasers operating in the transmission window of tissue at wavelengths between 700 and 800 nm are needed in numerous medical and biomedical applications, including photodynamic therapy and fluorescence microscopy. However, the performance of diode lasers in this spectral range is limited by the lack of appropriate compound semiconductors. Here, we review our recent research on 750 nm VECSELs. Two approaches to reaching the 750 nm wavelength will be discussed. The first approach relies on intra-cavity frequency doubling a wafer-fused 1500 nm VECSEL. The VECSEL gain chip comprises a GaAs-based DBR and an InP-based gain section, which allows for optical pumping with low-cost commercial diodes at 980 nm. With this scheme we have achieved watt-level output powers and tuning of the laser wavelength over a 40 nm band at around 750 nm. The second approach is direct emission at 750 nm using the AlGaAs/GaAs material system. In this approach visible wavelengths are required for optical pumping. However, the consequent higher costs compared to pumping at 980 nm are mitigated by the more compact laser setup and prospects of doubling the frequency to the ultraviolet range.

  6. Hypersensitisation using 266nm Laser Light

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Canning, John; Kristensen, Martin

    UV-hypersensitisation using 266nm VW-light on hydrogenated Ge-doped fibre is reported. The optimum fluence to be between 5 to 10 kJ/cm2, coinciding with results obtained using 355nm light, indicating same end-process in both reactions.......UV-hypersensitisation using 266nm VW-light on hydrogenated Ge-doped fibre is reported. The optimum fluence to be between 5 to 10 kJ/cm2, coinciding with results obtained using 355nm light, indicating same end-process in both reactions....

  7. Laser hypersensitisation using 266nm light

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Canning, J.; Kristensen, Martin

    2005-01-01

    UV hypersensitisation using CW 266 nm light on hydrogenated Ge-doped fibre is reported. The optimum sensitisation fluence is found to be in the range of 5 to 10 kJ/cm2, coinciding with previous results obtained using 355 nm light, indicating the same end-process used in the photochemical reaction...

  8. Capillary Condensation in 8 nm Deep Channels.

    Science.gov (United States)

    Zhong, Junjie; Riordon, Jason; Zandavi, Seyed Hadi; Xu, Yi; Persad, Aaron H; Mostowfi, Farshid; Sinton, David

    2018-02-01

    Condensation on the nanoscale is essential to understand many natural and synthetic systems relevant to water, air, and energy. Despite its importance, the underlying physics of condensation initiation and propagation remain largely unknown at sub-10 nm, mainly due to the challenges of controlling and probing such small systems. Here we study the condensation of n-propane down to 8 nm confinement in a nanofluidic system, distinct from previous studies at ∼100 nm. The condensation initiates significantly earlier in the 8 nm channels, and it initiates from the entrance, in contrast to channels just 10 times larger. The condensate propagation is observed to be governed by two liquid-vapor interfaces with an interplay between film and bridging effects. We model the experimental results using classical theories and find good agreement, demonstrating that this 8 nm nonpolar fluid system can be treated as a continuum from a thermodynamic perspective, despite having only 10-20 molecular layers.

  9. Effect of silica particle size on macrophage inflammatory responses.

    Directory of Open Access Journals (Sweden)

    Toshimasa Kusaka

    Full Text Available Amorphous silica particles, such as nanoparticles (<100 nm diameter particles, are used in a wide variety of products, including pharmaceuticals, paints, cosmetics, and food. Nevertheless, the immunotoxicity of these particles and the relationship between silica particle size and pro-inflammatory activity are not fully understood. In this study, we addressed the relationship between the size of amorphous silica (particle dose, diameter, number, and surface area and the inflammatory activity (macrophage phagocytosis, inflammasome activation, IL-1β secretion, cell death and lung inflammation. Irrespective of diameter size, silica particles were efficiently internalized by mouse bone marrow-derived macrophages via an actin cytoskeleton-dependent pathway, and induced caspase-1, but not caspase-11, activation. Of note, 30 nm-1000 nm diameter silica particles induced lysosomal destabilization, cell death, and IL-1β secretion at markedly higher levels than did 3000 nm-10000 nm silica particles. Consistent with in vitro results, intra-tracheal administration of 30 nm silica particles into mice caused more severe lung inflammation than that of 3000 nm silica particles, as assessed by measurement of pro-inflammatory cytokines and neutrophil infiltration in bronchoalveolar lavage fluid of mice, and by the micro-computed tomography analysis. Taken together, these results suggest that silica particle size impacts immune responses, with submicron amorphous silica particles inducing higher inflammatory responses than silica particles over 1000 nm in size, which is ascribed not only to their ability to induce caspase-1 activation but also to their cytotoxicity.

  10. Studies on nanosecond 532nm and 355nm and ultrafast 515nm and 532nm laser cutting super-hard materials

    Science.gov (United States)

    Zhang, Jie; Tao, Sha; Wang, Brian; Zhao, Jay

    2017-02-01

    In this paper, micro-processing of three kinds of super-hard materials of poly-crystal diamond (PCD)/tungsten-carbide (WC), CVD-diamond and cubic boron nitride (CNB) has been systematically studied using nanosecond laser (532nm and 355nm), and ultrafast laser (532nm and 515nm). Our purpose is to investigate a full laser micro-cutting solution to achieve a ready-to-use cutting tool insert (CTI). The results show a clean cut with little burns and recasting at edge. The cutting speed of 2-10mm/min depending on thickness was obtained. The laser ablation process was also studied by varying laser parameters (wavelength, pulse width, pulse energy, repetition rate) and tool path to improve cutting speed. Also, studies on material removal efficiency (MRE) of PCD/WC with 355nm-ns and 515nm-fs laser as a function of laser fluence show that 355nm-ns laser is able to achieve higher MRE for PCD and WC. Thus, ultrafast laser is not necessarily used for superhard material cutting. Instead, post-polishing with ultrafast laser can be used to clean cutting surface and improve smoothness.

  11. 308nm Excimer Laser in Dermatology

    Science.gov (United States)

    Mehraban, Shadi

    2014-01-01

    308nm xenon-chloride excimer laser, a novel mode of phototherapy, is an ultraviolet B radiation system consisting of a noble gas and halide. The aim of this systematic review was to investigate the literature and summarize all the experiments, clinical trials and case reports on 308-nm excimer laser in dermatological disorders. 308-nm excimer laser has currently a verified efficacy in treating skin conditions such as vitiligo, psoriasis, atopic dermatitis, alopecia areata, allergic rhinitis, folliculitis, granuloma annulare, lichen planus, mycosis fungoides, palmoplantar pustulosis, pityriasis alba, CD30+ lympho proliferative disorder, leukoderma, prurigo nodularis, localized scleroderma and genital lichen sclerosus. Although the 308-nm excimer laser appears to act as a promising treatment modality in dermatology, further large-scale studies should be undertaken in order to fully affirm its safety profile considering the potential risk, however minimal, of malignancy, it may impose. PMID:25606333

  12. PM Raman fiber laser at 1679 nm

    DEFF Research Database (Denmark)

    Svane, Ask Sebastian; Rottwitt, Karsten

    2012-01-01

    We demonstrate a PM Raman fiber laser emitting light at 1679 nm. The laser has an slope efficiency of 67 % and an output power of more than 275mWwith a 27 pm linewidth.......We demonstrate a PM Raman fiber laser emitting light at 1679 nm. The laser has an slope efficiency of 67 % and an output power of more than 275mWwith a 27 pm linewidth....

  13. 130-nm tunable grating-mirror VCSEL

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2014-01-01

    configuration instead of the extended cavity configuration can bring 130-nm tuning range around 1330-nm wavelength. The air-coupled cavity is known to reduce the quantum confinement factor in VCSELs, increasing threshold. In our air-coupled cavity HCG VCSEL case, the very short power penetration length...... in the HCG minimizes this reduction of the quantum confinement factor, not as significant as in the air-coupled cavity DBR VCSEL....

  14. Deposition and detection of particles during integrated circuit manufacturing

    NARCIS (Netherlands)

    Wali, F.; Knotter, D. Martin; Kelly, John J.; Kuper, F.G.

    2006-01-01

    Abstract—Deposition mechanism of silica particles on silicon wafers was investigated by depositing specially prepared mono-dispersed particles (mean diameter = 330 nm). To measure particles of the size below the detection limit of our particle measurement tools, silica particles with luminance core

  15. Particle size distribution control of Pt particles used for particle gun

    Science.gov (United States)

    Ichiji, M.; Akiba, H.; Nagao, H.; Hirasawa, I.

    2017-07-01

    The purpose of this study is particle size distribution (PSD) control of submicron sized Pt particles used for particle gun. In this report, simple reaction crystallization is conducted by mixing H2PtCl6 and ascorbic acid. Without the additive, obtained Pt particles have broad PSD and reproducibility of experiment is low. With seeding, Pt particles have narrow PSD and reproducibility improved. Additionally, mean particle diameter of 100-700 nm is controlled by changing seeding amount. Obtained particles are successfully characterized as Pt by XRD results. Moreover, XRD spectra indicate that obtained particles are polycrystals. These experimental results suggest that seeding consumed nucleation, as most nuclei attached on the seed surface. This mechanism virtually restricted nucleation to have narrow PSD can be obtained.

  16. Radiation Failures in Intel 14nm Microprocessors

    Science.gov (United States)

    Bossev, Dobrin P.; Duncan, Adam R.; Gadlage, Matthew J.; Roach, Austin H.; Kay, Matthew J.; Szabo, Carl; Berger, Tammy J.; York, Darin A.; Williams, Aaron; LaBel, K.; hide

    2016-01-01

    In this study the 14 nm Intel Broadwell 5th generation core series 5005U-i3 and 5200U-i5 was mounted on Dell Inspiron laptops, MSI Cubi and Gigabyte Brix barebones and tested with Windows 8 and CentOS7 at idle. Heavy-ion-induced hard- and catastrophic failures do not appear to be related to the Intel 14nm Tri-Gate FinFET process. They originate from a small (9 m 140 m) area on the 32nm planar PCH die (not the CPU) as initially speculated. The hard failures seem to be due to a SEE but the exact physical mechanism has yet to be identified. Some possibilities include latch-ups, charge ion trapping or implantation, ion channels, or a combination of those (in biased conditions). The mechanism of the catastrophic failures seems related to the presence of electric power (1.05V core voltage). The 1064 nm laser mimics ionization radiation and induces soft- and hard failures as a direct result of electron-hole pair production, not heat. The 14nm FinFET processes continue to look promising for space radiation environments.

  17. Response of Cloud Condensation Nuclei (> 50 nm) to changes in ion-nucleation

    DEFF Research Database (Denmark)

    Svensmark, Henrik; Enghoff, Martin B.; Pedersen, Jens Olaf Pepke

    2012-01-01

    In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulphur dioxide, and water vapour, the number of additional small particles produced by ionization by gamma sources all grow up to diameters larger than 50 nm, appropriate for cloud condensation nuclei. This res......In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulphur dioxide, and water vapour, the number of additional small particles produced by ionization by gamma sources all grow up to diameters larger than 50 nm, appropriate for cloud condensation nuclei...... finding points to a process not included in current theoretical models, possibly an ion-induced formation of sulphuric acid in small clusters....

  18. Diode laser (980nm) cartilage reshaping

    Science.gov (United States)

    El Kharbotly, A.; El Tayeb, T.; Mostafa, Y.; Hesham, I.

    2011-03-01

    Loss of facial or ear cartilage due to trauma or surgery is a major challenge to the otolaryngologists and plastic surgeons as the complicated geometric contours are difficult to be animated. Diode laser (980 nm) has been proven effective in reshaping and maintaining the new geometric shape achieved by laser. This study focused on determining the optimum laser parameters needed for cartilage reshaping with a controlled water cooling system. Harvested animal cartilages were angulated with different degrees and irradiated with different diode laser powers (980nm, 4x8mm spot size). The cartilage specimens were maintained in a deformation angle for two hours after irradiation then released for another two hours. They were serially measured and photographed. High-power Diode laser irradiation with water cooling is a cheep and effective method for reshaping the cartilage needed for reconstruction of difficult situations in otorhinolaryngologic surgery. Key words: cartilage,diode laser (980nm), reshaping.

  19. CALIPSO lidar calibration at 532 nm: version 4 nighttime algorithm

    Science.gov (United States)

    Kar, Jayanta; Vaughan, Mark A.; Lee, Kam-Pui; Tackett, Jason L.; Avery, Melody A.; Garnier, Anne; Getzewich, Brian J.; Hunt, William H.; Josset, Damien; Liu, Zhaoyan; Lucker, Patricia L.; Magill, Brian; Omar, Ali H.; Pelon, Jacques; Rogers, Raymond R.; Toth, Travis D.; Trepte, Charles R.; Vernier, Jean-Paul; Winker, David M.; Young, Stuart A.

    2018-03-01

    Data products from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) were recently updated following the implementation of new (version 4) calibration algorithms for all of the Level 1 attenuated backscatter measurements. In this work we present the motivation for and the implementation of the version 4 nighttime 532 nm parallel channel calibration. The nighttime 532 nm calibration is the most fundamental calibration of CALIOP data, since all of CALIOP's other radiometric calibration procedures - i.e., the 532 nm daytime calibration and the 1064 nm calibrations during both nighttime and daytime - depend either directly or indirectly on the 532 nm nighttime calibration. The accuracy of the 532 nm nighttime calibration has been significantly improved by raising the molecular normalization altitude from 30-34 km to the upper possible signal acquisition range of 36-39 km to substantially reduce stratospheric aerosol contamination. Due to the greatly reduced molecular number density and consequently reduced signal-to-noise ratio (SNR) at these higher altitudes, the signal is now averaged over a larger number of samples using data from multiple adjacent granules. Additionally, an enhanced strategy for filtering the radiation-induced noise from high-energy particles was adopted. Further, the meteorological model used in the earlier versions has been replaced by the improved Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), model. An aerosol scattering ratio of 1.01 ± 0.01 is now explicitly used for the calibration altitude. These modifications lead to globally revised calibration coefficients which are, on average, 2-3 % lower than in previous data releases. Further, the new calibration procedure is shown to eliminate biases at high altitudes that were present in earlier versions and consequently leads to an improved representation of

  20. Liquid Carbon Reflectivity at 19 nm

    Directory of Open Access Journals (Sweden)

    Riccardo Mincigrucci

    2015-01-01

    Full Text Available We hereby report on a pump-probe reflectivity experiment conducted on amorphous carbon, using a 780 nm laser as a pump and a 19 nm FEL emission as probe. Measurements were performed at 50 degrees with respect to the surface normal to have an un-pumped reflectivity higher than 0.5%. A sub-10 fs time synchronization error could be obtained exploiting the nearly jitter-free capabilities of FERMI. EUV FEL-based experiments open the way to study the behaviour of a liquid carbon phase being unaffected by plasma screening.

  1. Design of an 1800nm Raman amplifier

    DEFF Research Database (Denmark)

    Svane, Ask Sebastian; Rottwitt, Karsten

    2013-01-01

    We present the experimental results for a Raman amplifier that operates at 1810 nm and is pumped by a Raman fiber laser at 1680 nm. Both the pump laser and the Raman amplifier is polarization maintaining. A challenge when scaling Raman amplifiers to longer wavelengths is the increase...... in transmission loss, but also the reduction in the Raman gain coefficient as the amplifier wavelength is increased. Both polarization components of the Raman gain is characterized, initially for linearly co-polarized signal and pump, subsequently linearly polarized orthogonal signal and pump. The noise...

  2. Super ACO FEL oscillation at 300 nm

    CERN Document Server

    Nutarelli, D; Renault, E; Nahon, L; Couprie, Marie Emmanuelle

    2000-01-01

    Some recent improvements, involving both the optical cavity mirrors and the positron beam dynamics in the storage ring, have allowed us to achieve a laser oscillation at 300 nm on the Super ACO Storage Ring FEL. The Super ACO storage ring is operated at 800 MeV which is the nominal energy for the usual synchrotron radiation users, and the highest energy for a storage ring FEL. The lasing at 300 nm could be kept during 2 h per injection, with a stored current ranging between 30 and 60 mA. The FEL characteristics are presented here. The longitudinal stability and the FEL optics behaviour are also discussed.

  3. Organic antireflective coatings for 193-nm lithography

    Science.gov (United States)

    Trefonas, Peter, III; Blacksmith, Robert F.; Szmanda, Charles R.; Kavanagh, Robert J.; Adams, Timothy G.; Taylor, Gary N.; Coley, Suzanne; Pohlers, Gerd

    1999-06-01

    Organic anti-reflective coatings (ARCs) continue to play an important role in semiconductor manufacturing. These materials provide a convenient means of greatly reducing the resist photospeed swing and reflective notching. In this paper, we describe a novel class of ARC materials optimized for lithographic applications using 193 nm exposure tools. These ARCs are based upon polymers containing hydroxyl-alkyl methacrylate monomers for crosslinkable sites, styrene for a chromophore at 193 nm, and additional alkyl-methacrylate monomers as property modifiers. A glycouril crosslinker and a thermally-activated acidic catalyst provide a route to forming an impervious crosslinked film activate data high bake temperatures. ARC compositions can be adjusted to optimize the film's real and imaginary refractive indices. Selection of optimal target indices for 193 nm lithographic processing through simulations is described. Potential chromophores for 193 nm were explored using ZNDO modeling. We show how these theoretical studies were combined with material selection criteria to yield a versatile organic anti-reflectant film, Shipley 193 G0 ARC. Lithographic process data indicates the materials is capable of supporting high resolution patterning, with the line features displaying a sharp resist/ARC interface with low line edge roughness. The resist Eo swing is successfully reduced from 43 percent to 6 percent.

  4. Rare particles

    International Nuclear Information System (INIS)

    Kutschera, W.

    1984-01-01

    The use of Accelerator Mass Spectrometry (AMS) to search for hypothetical particles and known particles of rare processes is discussed. The hypothetical particles considered include fractionally charged particles, anomalously heavy isotopes, and superheavy elements. The known particles produced in rare processes discussed include doubly-charged negative ions, counting neutrino-produced atoms in detectors for solar neutrino detection, and the spontaneous emission of 14 C from 223 Ra. 35 references

  5. Alveolar macrophage accumulation rates, for 28 nm and 250 nm PSL, are mediated by separate mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Moss, O R; Wong, V A, E-mail: moss@thehamner.or [Hamner Institutes for Health Sciences, Research Triangle Park, NC 27509-2137 (United States)

    2009-02-01

    When macrophages accumulate 28 nm and 250 nm diameter polystyrene latex (PSL) beads, the accumulation rates should reflect differences in molecular and cellular function. We used a confocal microscope to measure the accumulation rates of nanoparticles by F344-rat-alveolar macrophages (approx25,000 cells adhered to a 0.7 cm{sup 2} surface). Over the cells were layered 0.1 ml of media, and 0.1 ml of media-with-beads. Fresh cells were introduced for each exposure scenario. The maximum possible individual macrophage exposures were as follows: 8x10{sup 6}, 8x10{sup 5}, and 8x10{sup 4} 28 nm beads per macrophage; and 8x10{sup 4} and 1.12x10{sup 4} 250 nm beads per macrophage. Accumulation rates were estimated over 23 minutes. The increase in bead accumulation-rate matched changes in bead-availability: 7x increase for 250 nm beads; 100x increase for 28 nm beads; and 700x increase for all bead availabilities. The maximum sustained 28 nm bead accumulation rate was > 30,000 /min (for 5 min). Increases in bead accumulation could be explained by two mechanisms: bead-diffusion; and, for the macrophage, macropinocytosis. Also for the highest concentrations of 28 nm beads, we saw a colligative threshold - possibly due to beads masking the cell surface or obstructing cellular mechanisms.

  6. Repair of near-UV (365nm or 313 nm) induced DNA strand breaks

    International Nuclear Information System (INIS)

    Miguel, A.G.

    1981-01-01

    The action of near-UV (365 nm or 313 nm) radiation in cellular inactivaton (biological measurements) and induction and repair of breaks (physical measurements) is studied in repair proficient strain and in pol A, rec A and uvr A deficient strains of Escherichia coli K-12. (M.A.C.) [pt

  7. Air bubble-induced detachment of polystyrene particles with different sizes from collector surfaces in a parallel plate flow chamber

    NARCIS (Netherlands)

    Gomez-Suarez, C; van der Mei, HC; Busscher, HJ

    2001-01-01

    Particle size was found to be an important factor in air bubble-induced detachment of colloidal particles from collector surfaces in a parallel plate flow chamber and generally polystyrene particles with a diameter of 806 nm detached less than particles with a diameter of 1400 nm. Particle

  8. NM-Scale Anatomy of an Entire Stardust Carrot Track

    Science.gov (United States)

    Nakamura-Messenger, K.; Keller, L. P.; Clemett, S. J.; Messenger, S.

    2009-01-01

    Comet Wild-2 samples collected by NASA s Stardust mission are extremely complex, heterogeneous, and have experienced wide ranges of alteration during the capture process. There are two major types of track morphologies: "carrot" and "bulbous," that reflect different structural/compositional properties of the impactors. Carrot type tracks are typically produced by compact or single mineral grains which survive essentially intact as a single large terminal particle. Bulbous tracks are likely produced by fine-grained or organic-rich impactors [1]. Owing to their challenging nature and especially high value of Stardust samples, we have invested considerable effort in developing both sample preparation and analytical techniques tailored for Stardust sample analyses. Our report focuses on our systematic disassembly and coordinated analysis of Stardust carrot track #112 from the mm to nm-scale.

  9. Photochemistry of acrylates at 222 nm

    International Nuclear Information System (INIS)

    Knolle, Wolfgang; Naumov, Sergej; Madani, Mohamed; Sonntag, Clemens von

    2005-01-01

    Excimer lamps as monochromatic UV sources with an intense short-wavelength emission (especially KrCl * , 222 nm) allow a photoinitiator-free initiation of the acrylate polymerisation. Laser photolysis (KrCl * excimer laser, pulse width 20 ns, up to 5 mJ per pulse) gives rise to similar transient spectra (λ max ∼ 280 nm) for all acrylates studied. As the rather unspecific spectra do not allow conclusions as to the main reaction channel, a product study has been performed by GC-MS following steady-state photolysis of acrylate solutions in acetonitrile, methanol and n-hexane. Somewhat unexpected, α-cleavage seems to be a main reaction channel, and quantum chemical calculations show that such a reaction can occur from either the excited singlet state or the unrelaxed triplet state, but not from the relaxed triplet state that is observed spectroscopically. A reaction scheme accounting for the observed products is presented

  10. Study of heat generation and cutting force according to minimization of grain size (500 nm to 180 nm) of WC ball endmill using FEM

    Science.gov (United States)

    Byeon, J. H.; Ahmed, F.; Ko, T. J.; lee, D. K.; Kim, J. S.

    2018-03-01

    As the industry develops, miniaturization and refinement of products are important issues. Precise machining is required for cutting, which is a typical method of machining a product. The factor determining the workability of the cutting process is the material of the tool. Tool materials include carbon tool steel, alloy tool steel, high-speed steel, cemented carbide, and ceramics. In the case of a carbide material, the smaller the particle size, the better the mechanical properties with higher hardness, strength and toughness. The specific heat, density, and thermal diffusivity are also changed through finer particle size of the material. In this study, finite element analysis was performed to investigate the change of heat generation and cutting power depending on the physical properties (specific heat, density, thermal diffusivity) of tool material. The thermal conductivity coefficient was obtained by measuring the thermal diffusivity, specific heat, and density of the material (180 nm) in which the particle size was finer and the particle material (0.05 μm) in the conventional size. The coefficient of thermal conductivity was calculated as 61.33 for 180nm class material and 46.13 for 0.05μm class material. As a result of finite element analysis using this value, the average temperature of exothermic heat of micronized particle material (180nm) was 532.75 °C and the temperature of existing material (0.05μm) was 572.75 °C. Cutting power was also compared but not significant. Therefore, if the thermal conductivity is increased through particle refinement, the surface power can be improved and the tool life can be prolonged by lowering the temperature generated in the tool during machining without giving a great influence to the cutting power.

  11. Design of Polymer Wavelength Splitter 1310 nm/1550 nm Based on Multimode Interferences

    Directory of Open Access Journals (Sweden)

    V. Prajzler

    2010-12-01

    Full Text Available We report about design of 1x2 1310/1550 nm optical wavelength division multiplexer based on polymer waveguides. The polymer splitter was designed by using RSoft software based on beam propagation method. Epoxy novolak resin polymer was used as core waveguides layer, silicon substrate with silica layer was used as buffer layer and polymethylmethacrylate was used as protection cover layer. The simulation shows that the output energy for the fundamental mode is 67.1 % for 1310 nm and 67.8 % for 1550 nm wavelength.

  12. Particle hygroscopicity during atmospheric new particle formation events: implications for the chemical species contributing to particle growth

    Directory of Open Access Journals (Sweden)

    Z. Wu

    2013-07-01

    Full Text Available This study examines the hygroscopicity of newly formed particles (diameters range 25–45 nm during two atmospheric new particle formation (NPF events in the German mid-level mountains during the Hill Cap Cloud Thuringia 2010 (HCCT-2010 field experiment. At the end of the NPF event involving clear particle growth, we measured an unusually high soluble particle fraction of 58.5% at 45 nm particle size. The particle growth rate contributed through sulfuric acid condensation only accounts for around 6.5% of the observed growth rate. Estimations showed that sulfuric acid condensation explained, however, only around 10% of that soluble particle fraction. Therefore, the formation of additional water-soluble matter appears imperative to explain the missing soluble fraction. Although direct evidence is missing, we consider water-soluble organics as candidates for this mechanism. For the case with clear growth process, the particle growth rate was determined by two alternative methods based on tracking the mode diameter of the nucleation mode. The mean particle growth rate obtained from the inter-site data comparison using Lagrangian consideration is 3.8 (± 2.6 nm h−1. During the same period, the growth rate calculated based on one site data is 5.0 nm h−1 using log-normal distribution function method. In light of the fact that considerable uncertainties could be involved in both methods, we consider both estimated growth rates consistent.

  13. Particle detection

    International Nuclear Information System (INIS)

    Charpak, G.

    2000-01-01

    In this article G.Charpak presents the principles on which particle detection is based. Particle accelerators are becoming more and more powerful and require new detectors able to track the right particle in a huge flux of particles. The gigantic size of detectors in high energy physics is often due to the necessity of getting a long enough trajectory in a magnetic field in order to deduce from the curvature an accurate account of impulses in the reaction. (A.C.)

  14. Passively mode-locked Nd:YVO4 laser operating at 1073 nm and 1085 nm

    Science.gov (United States)

    Waritanant, Tanant; Major, Arkady

    2018-02-01

    A passively mode-locked Nd:YVO4 laser operating at 1073 nm and 1085 nm was demonstrated with an intracavity birefringent filter as the wavelength selecting element. The average output powers achieved were 2.17 W and 2.18 W with optical-to-optical efficiency of 19.6% and 19.7%, respectively. The slope efficiencies were more than 31% at both output wavelengths. The pulse durations at the highest average output power were 10.3 ps and 8.4 ps, respectively. We believe that this is the first report of mode locking of a Nd:YVO4 laser operating at 1073 nm or 1085 nm lines.

  15. Strange particles

    International Nuclear Information System (INIS)

    Chinowsky, W.

    1989-01-01

    Work done in the mid 1950s at Brookhaven National Laboratory on strange particles is described. Experiments were done on the Cosmotron. The author describes his own and others' work on neutral kaons, lambda and theta particles and points out the theoretical gap between predictions and experimental findings. By the end of the decade, the theory of strange particles was better understood. (UK)

  16. Harmonic Inverse FEL Interaction at 800nm

    CERN Document Server

    Sears, C M S; Siemann, R; Spencer, J E

    2005-01-01

    The inverse Free Electron Laser (IFEL) interaction has recently been proposed and demonstrated as a premodulator for High Gain Harmonic Generation (HGHG) experiments. These experiments utilized the fundamental of the interaction between the laser field and electron bunch. In the current experiment, we explore the higher order resonances of the IFEL interaction from a 3 period, 1.8 centimeter wavelength undulator with a picosecond, 0.25 mJ/pulse laser at 800nm. The resonances are observed by adjusting the gap of the undulator while keeping the beam energy constant. The harmonic IFEL can add flexibility to HGHG FEL design.

  17. Laser–fibre vibrometry at 1550 nm

    International Nuclear Information System (INIS)

    Waz, A T; Kaczmarek, P R; Abramski, K M

    2009-01-01

    This paper presents new solutions for laser vibrometry, which are based on fibre vibrometry in the third telecommunication window. The scattered laser beam from a vibrating object is guided by a fibre collimator and coherently detected through heterodyning it with an acousto-optical frequency-shifted reference beam. The concept of measuring vibration parameters from many points of the vibrating object has been inspired by wavelength division multiplexing (WDM) in fibre telecommunications. The N-independent WDM separated 15XX nm fibre-coupled laser diodes (used for optical fibre telecommunications) form a system of sources for multipoint vibration measurement according to the rule 'one wavelength–one point'

  18. Bounce behavior of freshly nucleated biogenic secondary organic aerosol particles

    Directory of Open Access Journals (Sweden)

    A. Virtanen

    2011-08-01

    Full Text Available The assessment of the climatic impacts and adverse health effects of atmospheric aerosol particles requires detailed information on particle properties. However, very limited information is available on the morphology and phase state of secondary organic aerosol (SOA particles. The physical state of particles greatly affects particulate-phase chemical reactions, and thus the growth rates of newly formed atmospheric aerosol. Thus verifying the physical phase state of SOA particles gives new and important insight into their formation, subsequent growth, and consequently potential atmospheric impacts. According to our recent study, biogenic SOA particles produced in laboratory chambers from the oxidation of real plant emissions as well as in ambient boreal forest atmospheres can exist in a solid phase in size range >30 nm. In this paper, we extend previously published results to diameters in the range of 17–30 nm. The physical phase of the particles is studied by investigating particle bounce properties utilizing electrical low pressure impactor (ELPI. We also investigate the effect of estimates of particle density on the interpretation of our bounce observations. According to the results presented in this paper, particle bounce clearly decreases with decreasing particle size in sub 30 nm size range. The comparison measurements by ammonium sulphate and investigation of the particle impaction velocities strongly suggest that the decreasing bounce is caused by the differences in composition and phase of large (diameters greater than 30 nm and smaller (diameters between 17 and 30 nm particles.

  19. Synthesis of Cationic Core-Shell Latex Particles

    NARCIS (Netherlands)

    Dziomkina, N.; Hempenius, Mark A.; Vancso, Gyula J.

    2006-01-01

    Surfactant-free seeded (core-shell) polymerization of cationic polymer colloids is presented. Polystyrene core particles with sizes between 200 nm and 500 nm were synthesized. The number average diameter of the colloidal core particles increased with increasing monomer concentration. Cationic shells

  20. Ultralow-Power Electronic Trapping of Nanoparticles with Sub-10 nm Gold Nanogap Electrodes.

    Science.gov (United States)

    Barik, Avijit; Chen, Xiaoshu; Oh, Sang-Hyun

    2016-10-12

    We demonstrate nanogap electrodes for rapid, parallel, and ultralow-power trapping of nanoparticles. Our device pushes the limit of dielectrophoresis by shrinking the separation between gold electrodes to sub-10 nm, thereby creating strong trapping forces at biases as low as the 100 mV ranges. Using high-throughput atomic layer lithography, we manufacture sub-10 nm gaps between 0.8 mm long gold electrodes and pattern them into individually addressable parallel electronic traps. Unlike pointlike junctions made by electron-beam lithography or larger micron-gap electrodes that are used for conventional dielectrophoresis, our sub-10 nm gold nanogap electrodes provide strong trapping forces over a mm-scale trapping zone. Importantly, our technology solves the key challenges associated with traditional dielectrophoresis experiments, such as high voltages that cause heat generation, bubble formation, and unwanted electrochemical reactions. The strongly enhanced fields around the nanogap induce particle-transport speed exceeding 10 μm/s and enable the trapping of 30 nm polystyrene nanoparticles using an ultralow bias of 200 mV. We also demonstrate rapid electronic trapping of quantum dots and nanodiamond particles on arrays of parallel traps. Our sub-10 nm gold nanogap electrodes can be combined with plasmonic sensors or nanophotonic circuitry, and their low-power electronic operation can potentially enable high-density integration on a chip as well as portable biosensing.

  1. High power diode lasers emitting from 639 nm to 690 nm

    Science.gov (United States)

    Bao, L.; Grimshaw, M.; DeVito, M.; Kanskar, M.; Dong, W.; Guan, X.; Zhang, S.; Patterson, J.; Dickerson, P.; Kennedy, K.; Li, S.; Haden, J.; Martinsen, R.

    2014-03-01

    There is increasing market demand for high power reliable red lasers for display and cinema applications. Due to the fundamental material system limit at this wavelength range, red diode lasers have lower efficiency and are more temperature sensitive, compared to 790-980 nm diode lasers. In terms of reliability, red lasers are also more sensitive to catastrophic optical mirror damage (COMD) due to the higher photon energy. Thus developing higher power-reliable red lasers is very challenging. This paper will present nLIGHT's released red products from 639 nm to 690nm, with established high performance and long-term reliability. These single emitter diode lasers can work as stand-alone singleemitter units or efficiently integrate into our compact, passively-cooled Pearl™ fiber-coupled module architectures for higher output power and improved reliability. In order to further improve power and reliability, new chip optimizations have been focused on improving epitaxial design/growth, chip configuration/processing and optical facet passivation. Initial optimization has demonstrated promising results for 639 nm diode lasers to be reliably rated at 1.5 W and 690nm diode lasers to be reliably rated at 4.0 W. Accelerated life-test has started and further design optimization are underway.

  2. Compact corner-pumped Nd:YAG/YAG composite slab 1319 nm/1338 nm laser

    International Nuclear Information System (INIS)

    Liu, H; Gong, M; Wushouer, X; Gao, S

    2010-01-01

    A corner-pumped type is a new pumping type in the diode-pumped solid-state lasers, which has the advantages of high pump efficiency and favorable pump uniformity. A corner-pumped Nd:YAG/YAG composite slab continuous-wave 1319 nm/1338 nm dual-wavelength laser is first demonstrated in this paper. When the cavity length is 25 mm, the maximal output power is up to 7.62 W with a slope efficiency of 16.6% and an optical-to-optical conversion efficiency of 17%. The corresponding spectral line widths of 1319 nm laser and 1338 nm laser are 0.11 and 0.1 nm, respectively. The short-term instability of the output power is better than 1% when the pumping power is 39.5 W. The experimental results show that a corner-pumped type is a kind of feasible schedules in the design of diode-pumped solid-state 1.3 μm lasers with low or medium output powers

  3. Comparison of 193 nm and 308 nm laser liquid printing by shadowgraphy imaging

    Energy Technology Data Exchange (ETDEWEB)

    Palla-Papavlu, A., E-mail: apalla@nipne.ro [National Institute for Lasers, Plasma and Radiation Physics, P.O. Box MG-36, Magurele, RO-077125 Bucharest (Romania); Shaw-Stewart, J. [EMPA, Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Functional Polymers, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Paul Scherrer Institute, General Energy Research Department, 5232 Villigen PSI (Switzerland); Mattle, T. [Paul Scherrer Institute, General Energy Research Department, 5232 Villigen PSI (Switzerland); Dinca, V. [National Institute for Lasers, Plasma and Radiation Physics, P.O. Box MG-36, Magurele, RO-077125 Bucharest (Romania); Lippert, T.; Wokaun, A. [Paul Scherrer Institute, General Energy Research Department, 5232 Villigen PSI (Switzerland); Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, P.O. Box MG-36, Magurele, RO-077125 Bucharest (Romania)

    2013-08-01

    Over the last years laser-induced forward transfer has emerged as a versatile and powerful tool for engineering surfaces with active compounds. Soft, easily damageable materials can be transferred using a triazene polymer as a sacrificial layer which acts as a pressure generator and at the same time protects the material from direct laser irradiation. To understand and optimize the transfer process of biomolecules in liquid solution by using an intermediate triazene polymer photosensitive layer, shadowgraphy imaging is carried out. Two laser systems i.e. an ArF laser operating at 193 nm and a XeCl laser operating at 308 nm are applied for the transfer. Solutions with 50% v/v glycerol concentration are prepared and the influence of the triazene polymer sacrificial layer thickness (60 nm) on the deposits is studied. The shadowgraphy images reveal a pronounced difference between laser-induced forward transfer using 193 nm or 308 nm, i.e. very different shapes of the ejected liquid.

  4. Read-through transcript from NM23-H1 into the neighboring NM23-H2 gene encodes a novel protein, NM23-LV

    NARCIS (Netherlands)

    Valentijn, Linda J.; Koster, Jan; Versteeg, Rogier

    2006-01-01

    NM23-H1 and NM23-H2 are neighboring genes on chromosome 17q. They encode nucleoside diphosphate kinases that have additional roles in signal transduction, transcription, and apoptosis. NM23-H1 expression is a strong marker for prognosis and metastatic behavior in many tumor types. A new

  5. 308-nm excimer laser in endodontics

    Science.gov (United States)

    Liesenhoff, Tim

    1992-06-01

    Root canal preparation was performed on 20 extracted human teeth. After opening the coronal pulp, the root canals were prepared by 308 nm excimer laser only. All root canals were investigated under SEM after separation in the axial direction. By sagittal separation of the mandibles of freshly slaughtered cows, it was possible to get access to the tissues and irradiate under optical control. Under irradiation of excimer laser light, tissue starts to fluoresce. It was possible to demonstrate that each tissue (dentin, enamel, bone, pulpal, and connective tissue) has a characteristic spectral pattern. The SEM analyses showed that it is well possible to prepare root canals safely. All organic soft tissue has been removed by excimer laser irradiation. There was no case of via falsa. The simultaneous spectroscopic identification of the irradiated tissue provides a safe protection from overinstrumentation. First clinical trials on 20 patients suffering of chronical apical parodontitis have been carried out successfully.

  6. Ocular effects of ultraviolet radiation from 295 to 365 nm

    International Nuclear Information System (INIS)

    Pitts, D.G.; Cullen, A.P.; Hacker, P.D.

    1977-01-01

    A 5,000 watt Xe--Hg source and a double monochromator were used to produce 6.6 nm full band-pass ultraviolet (UV) radiation. Pigmented rabbit eyes were exposed to the 6.6 nm band-pass UV radiant energy in 5 nm steps from 295 to 320 nm and at random intervals above 320 nm. Corneal and lenticular damage was assessed and classified with a biomicroscope. Corneal threshold radiant exposure (Hc) rose very rapidly from 0.022 Jcm -2 at 300 nm to 10.99 Jcm -2 at 335 nm. Radiant exposures exceeding 2 x Hc resulted in irreversible corneal damage. Lenticular damage was limited to wavebands above 295 nm. The action spectrum for the lens began at 295 nm and extended to about 315 nm. Permanent lenticular damage occurred at radiant exposure levels approximately twice the threshold for lenticular radiant exposure. The importance in establishing both corneal and lenticular damage criteria is emphasized

  7. Particle therapy

    Energy Technology Data Exchange (ETDEWEB)

    Raju, M.R.

    1993-09-01

    Particle therapy has a long history. The experimentation with particles for their therapeutic application got started soon after they were produced in the laboratory. Physicists played a major role in proposing the potential applications in radiotherapy as well as in the development of particle therapy. A brief review of the current status of particle radiotherapy with some historical perspective is presented and specific contributions made by physicists will be pointed out wherever appropriate. The rationale of using particles in cancer treatment is to reduce the treatment volume to the target volume by using precise dose distributions in three dimensions by using particles such as protons and to improve the differential effects on tumors compared to normal tissues by using high-LET radiations such as neutrons. Pions and heavy ions combine the above two characteristics.

  8. Particle therapy

    International Nuclear Information System (INIS)

    Raju, M.R.

    1993-01-01

    Particle therapy has a long history. The experimentation with particles for their therapeutic application got started soon after they were produced in the laboratory. Physicists played a major role in proposing the potential applications in radiotherapy as well as in the development of particle therapy. A brief review of the current status of particle radiotherapy with some historical perspective is presented and specific contributions made by physicists will be pointed out wherever appropriate. The rationale of using particles in cancer treatment is to reduce the treatment volume to the target volume by using precise dose distributions in three dimensions by using particles such as protons and to improve the differential effects on tumors compared to normal tissues by using high-LET radiations such as neutrons. Pions and heavy ions combine the above two characteristics

  9. Diurnal and seasonal variations of concentration and size distribution of nano aerosols (10-1100 nm) enclosing radon decay products in the Postojna Cave, Slovenia.

    Science.gov (United States)

    Bezek, M; Gregoric, A; Kávási, N; Vaupotic, J

    2012-11-01

    At the lowest point along the tourist route in the Postojna Cave, the activity concentration of radon ((222)Rn) short-lived decay products and number concentration and size distribution of background aerosol particles in the size range of 10-1100 nm were measured. In the warm yearly season, aerosol concentration was low (52 cm(-3)) with 21 % particles smaller than 50 nm, while in the cold season, it was higher (1238 cm(-3)) with 8 % of <50 nm particles. Radon activity concentrations were 4489 and 1108 Bq m(-3), and fractions of unattached radon decay products were 0.62 and 0.13, respectively.

  10. Particle cosmology

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    The understanding of the Universe at the largest and smallest scales traditionally has been the subject of cosmology and particle physics, respectively. Studying the evolution of the Universe connects today's large scales with the tiny scales in the very early Universe and provides the link between the physics of particles and of the cosmos. This series of five lectures aims at a modern and critical presentation of the basic ideas, methods, models and observations in today's particle cosmology.

  11. Particle Emissions from Domestic Gas Cookers

    DEFF Research Database (Denmark)

    Glarborg, Peter; Livbjerg, Hans; Wagner, Ayten Yilmaz

    2010-01-01

    The authors experimentally studied the formation of submicron particles from a domestic gas cooker in a compartment free from external particle sources. The effects of fuel (methane, natural gas, odorant-free natural gas), primary aeration, flow rate, and fuel sulphur content on particle emissions...... of the emitted particles were found to have a mean value of about 7 nm for partially premixed flames, increasing to ∼10 nm for nonpremixed flames. The quantity of primary air had a strong impact on the particle emissions, showing a minimum at a primary aeration level of 60-65%. Presence of sulphur in small...... quantities may enhance particle formation under some conditions, but results were not conclusive....

  12. Absolute frequency atlas from 915 nm to 985 nm based on laser absorption spectroscopy of iodine

    Science.gov (United States)

    Nölleke, Christian; Raab, Christoph; Neuhaus, Rudolf; Falke, Stephan

    2018-04-01

    This article reports on laser absorption spectroscopy of iodine gas between 915 nm and 985 nm. This wavelength range is scanned utilizing a narrow linewidth and mode-hop-free tunable diode-laser whose frequency is actively controlled using a calibrated wavelength meter. This allows us to provide an iodine atlas that contains almost 10,000 experimentally observed reference lines with an uncertainty of 50 MHz. For common lines, good agreement is found with a publication by Gerstenkorn and Luc (1978). The new rich dataset allows existing models of the iodine molecule to be refined and can serve as a reference for laser frequency calibration and stabilization.

  13. Particle physics

    International Nuclear Information System (INIS)

    Kamal, Anwar

    2014-01-01

    Provides step-by-step derivations. Contains numerous tables and diagrams. Supports learning and teaching with numerous worked examples, questions and problems with answers. Sketches also the historical development of the subject. This textbook teaches particle physics very didactically. It supports learning and teaching with numerous worked examples, questions and problems with answers. Numerous tables and diagrams lead to a better understanding of the explanations. The content of the book covers all important topics of particle physics: Elementary particles are classified from the point of view of the four fundamental interactions. The nomenclature used in particle physics is explained. The discoveries and properties of known elementary particles and resonances are given. The particles considered are positrons, muon, pions, anti-protons, strange particles, neutrino and hadrons. The conservation laws governing the interactions of elementary particles are given. The concepts of parity, spin, charge conjugation, time reversal and gauge invariance are explained. The quark theory is introduced to explain the hadron structure and strong interactions. The solar neutrino problem is considered. Weak interactions are classified into various types, and the selection rules are stated. Non-conservation of parity and the universality of the weak interactions are discussed. Neutral and charged currents, discovery of W and Z bosons and the early universe form important topics of the electroweak interactions. The principles of high energy accelerators including colliders are elaborately explained. Additionally, in the book detectors used in nuclear and particle physics are described. This book is on the upper undergraduate level.

  14. Magnetic particles

    Science.gov (United States)

    Chang, Manchium (Inventor); Colvin, Michael S. (Inventor)

    1989-01-01

    Magnetic polymer particles are formed by swelling porous, polymer particles and impregnating the particles with an aqueous solution of precursor magnetic metal salt such as an equimolar mixture of ferrous chloride and ferric chloride. On addition of a basic reagent such as dilute sodium hydroxide, the metal salts are converted to crystals of magnetite which are uniformly contained througout the pores of the polymer particle. The magnetite content can be increased and neutral buoyancy achieved by repetition of the impregnaton and neutralization steps to adjust the magnetite content to a desired level.

  15. Laser Shock Processing of 6061-T6 Al alloy with 1064 nm and 532 nm wavelengths

    International Nuclear Information System (INIS)

    Gomez-Rosas, G.; Rubio-Gonzalez, C.; Ocana, J.L.; Molpeceres, C.; Porro, J.A.; Morales, M.; Casillas, F.J.

    2010-01-01

    Laser Shock Processing (LSP) has been proposed as a competitive alternative technology to classical treatments for improving fatigue and wear resistance of metals. We present a configuration and results in the LSP concept for metal surface treatments in underwater laser irradiation at 532 nm and 1064 nm. The purpose of the work is to compare the effect of both wavelengths on the same material. A convergent lens is used to deliver 1.2 J/pulse (1064 nm) and 0.9 J/pulse (532 nm) in a 8 ns laser FWHM pulse produced by 10 Hz Q-switched Nd:YAG laser with spots of a 1.5 mm in diameter moving forward along the work piece. A LSP configuration with experimental results using a pulse density of 2500 pulses/cm 2 and 5000 pulses/cm 2 in 6061-T6 aluminum samples are presented. High level compressive residual stresses are produced using both wavelengths. It has been shown that surface residual stress level is comparable to that achieved by conventional shot peening, but with greater depths. This method can be applied to surface treatment of final metal products.

  16. Characterization of LANDSAT Panels Using the NIST BRDF Scale from 1100 nm to 2500 nm

    Science.gov (United States)

    Markham, Brian; Tsai, Benjamin K.; Allen, David W.; Cooksey, Catherine; Yoon, Howard; Hanssen, Leonard; Zeng, Jinan; Fulton, Linda; Biggar, Stuart; Markham, Brian

    2010-01-01

    Many earth observing sensors depend on white diffuse reflectance standards to derive scales of radiance traceable to the St Despite the large number of Earth observing sensors that operate in the reflective solar region of the spectrum, there has been no direct method to provide NIST traceable BRDF measurements out to 2500 rim. Recent developments in detector technology have allowed the NIST reflectance measurement facility to expand the operating range to cover the 250 nm to 2500 nm range. The facility has been modified with and additional detector using a cooled extended range indium gallium arsenide (Extended InGaAs) detector. Measurements were made for two PTFE white diffuse reflectance standards over the 1100 nm to 2500 nm region at a 0' incident and 45' observation angle. These two panels will be used to support the OLI calibration activities. An independent means of verification was established using a NIST radiance transfer facility based on spectral irradiance, radiance standards and a diffuse reflectance plaque. An analysis on the results and associated uncertainties will be discussed.

  17. Particle accelerator

    International Nuclear Information System (INIS)

    Ress, R.I.

    1976-01-01

    Charged particles are entrained in a predetermined direction, independent of their polarity, in a circular orbit by a magnetic field rotating at high speed about an axis in a closed cylindrical or toroidal vessel. The field may be generated by a cylindrical laser structure, whose beam is polygonally reflected from the walls of an excited cavity centered on the axis, or by high-frequency energization of a set of electromagnets perpendicular to the axis. In the latter case, a separate magnetostatic axial field limits the orbital radius of the particles. These rotating and stationary magnetic fields may be generated centrally or by individual magnets peripherally spaced along its circular orbit. Chemical or nuclear reactions can be induced by collisions between the orbiting particles and an injected reactant, or by diverting high-speed particles from one doughnut into the path of counterrotating particles in an adjoining doughnut

  18. Laser guidance of mesoscale particles

    Science.gov (United States)

    Underdown, Frank Hartman, Jr.

    Mesoscale particles are guided and trapped in hollow optical fibers using radiation pressure forces. Laser light from a 0.4W, 780nm diode laser is guided in a low- loss fiber mode and used to generate the guidance forces. Laser scattering and absorption forces propels particles along the fiber and polarization gradient forces attract them to the fiber's axial center. Using two counter propagating laser beams, inside the fiber, particles can be trapped in three dimensions. Measuring the spring constant of the trap gives the gradient force. This dissertation describes Rayleigh and Mie scattering models for calculating guidance forces. Calculated forces as a function of particle size and composition (i.e. dielectric, semiconductor, and metals) will be presented. For example, under typical experimental conditions 100nm Au particles are guided by a 2 × 10-14 N propulsive force in a water filled fiber. In comparison, the measured force, obtained from the particle's velocity and Stokes' law, is 7.98 × 10-14 N.

  19. Article coated with flash bonded superhydrophobic particles

    Science.gov (United States)

    Simpson, John T [Clinton, TN; Blue, Craig A [Knoxville, TN; Kiggans, Jr., James O [Oak Ridge, TN

    2010-07-13

    A method of making article having a superhydrophobic surface includes: providing a solid body defining at least one surface; applying to the surface a plurality of diatomaceous earth particles and/or particles characterized by particle sizes ranging from at least 100 nm to about 10 .mu.m, the particles being further characterized by a plurality of nanopores, wherein at least some of the nanopores provide flow through porosity, the particles being further characterized by a plurality of spaced apart nanostructured features that include a contiguous, protrusive material; flash bonding the particles to the surface so that the particles are adherently bonded to the surface; and applying a hydrophobic coating layer to the surface and the particles so that the hydrophobic coating layer conforms to the nanostructured features.

  20. Effectiveness of the Top-Down Nanotechnology in the Production of Ultrafine Cement (~220 nm

    Directory of Open Access Journals (Sweden)

    Byung-Wan Jo

    2014-01-01

    Full Text Available The present investigation is dealing with the communition of the cement particle to the ultrafine level (~220 nm utilizing the bead milling process, which is considered as a top-down nanotechnology. During the grinding of the cement particle, the effect of various parameters such as grinding time (1–6 h and grinding agent (methanol and ethanol on the production of the ultrafine cement has also been investigated. Performance of newly produced ultrafine cement is elucidated by the chemical composition, particle size distribution, and SEM and XRD analyses. Based on the particle size distribution of the newly produced ultrafine cement, it was assessed that the size of the cement particle decreases efficiently with increase in grinding time. Additionally, it is optimized that the bead milling process is able to produce 90% of the cement particle <350 nm and 50% of the cement particle < 220 nm, respectively, after 6.3 h milling without affecting the chemical phases. Production of the ultrafine cement utilizing this method will promote the construction industries towards the development of smart and sustainable construction materials.

  1. PILOT STUDY: Report on the CCPR Pilot Comparison: Spectral Responsivity 10 nm to 20 nm

    Science.gov (United States)

    Scholze, Frank; Vest, Robert; Saito, Terubumi

    2010-01-01

    The CCPR Pilot Comparison on spectral responsivity in the 10 nm to 20 nm spectral range was carried out within the framework of the CIPM Mutual Recognition Arrangement by three laboratories: PTB (Germany), NIST (USA), and NMIJ/AIST (Japan) with PTB acting as the central and reporting laboratory. All participating laboratories used monochromatized synchrotron radiation. PTB and NIST used a cryogenic radiometer as the primary standard detector and NMIJ, an ionization chamber with extrapolation by a wavelength-independent detector. The aim of the pilot comparison was to check the accuracy of the radiometric scale of spectral responsivity in the short wavelength EUV spectral range which has recently gained in technological importance. The wavelengths of measurement were from 11.5 nm to 20 nm in 0.5 nm steps and additionally 12.2 nm. The comparison was carried out through the calibration of a group of transfer standard detectors. Two sets of three diodes of types AXUV and SXUV from International Radiation Detectors, Inc. were used for the comparison. The comparison had the form of a star comparison: Pilot-lab A-pilot-lab B-pilot, PTB acting as the pilot laboratory. All results were communicated directly to the pilot laboratory. The report describes in detail the measurements made at PTB and summarizes the reports submitted by the participants. Measurements carried out by the pilot laboratory before and after the circulation of the detectors proved that the stability of the detectors was sufficient for the comparison. For the type AXUV detectors, however, changes in their responsivity contributed to the uncertainty of the comparison. Measurement results from participants and their associated uncertainties were analyzed in this report according to the Guidelines for CCPR Comparison Report Preparation. The uncertainty contributions were separated, as to whether they are wavelength dependent or not. All bilateral DoE are well within the respective k = 2 expanded uncertainty

  2. Synthesis and characterization of mesoporous silica core-shell particles

    Directory of Open Access Journals (Sweden)

    Milan Nikolić

    2010-06-01

    Full Text Available Core-shell particles were formed by deposition of primary silica particles synthesized from sodium silicate solution on functionalized silica core particles (having size of ~0.5 µm prepared by hydrolysis and condensation of tetraethylortosilicate. The obtained mesoporous shell has thickness of about 60 nm and consists of primary silica particles with average size of ~21 nm. Scanning electron microscopy and zeta potential measurements showed that continuous silica shell exists around functionalized core particles which was additionally proved by FTIR and TEM results.

  3. TSI Model 3936 Scanning Mobility Particle Spectrometer Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Kuang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-01

    The Model 3936 Scanning Mobility Particle Spectrometer (SMPS) measures the size distribution of aerosols ranging from 10 nm up to 1000 nm. The SMPS uses a bipolar aerosol charger to keep particles within a known charge distribution. Charged particles are classified according to their electrical mobility, using a long-column differential mobility analyzer (DMA). Particle concentration is measured with a condensation particle counter (CPC). The SMPS is well-suited for applications including: nanoparticle research, atmospheric aerosol studies, pollution studies, smog chamber evaluations, engine exhaust and combustion studies, materials synthesis, filter efficiency testing, nucleation/condensation studies, and rapidly changing aerosol systems.

  4. Magnetic Susceptibility of liquid Gd-NM (NM = Cu, Ga, Ge alloys

    Directory of Open Access Journals (Sweden)

    Shimakura Hironori

    2017-01-01

    Full Text Available For rare earth alloys, the indirect interaction of RKKY is at work between rare-earth atoms. Therefore, the magnetism of them depends on the number of conduction electrons and the distance between rare-earth metals. In this work, to reveal the relationship between the number of conduction electrons and magnetic property of rare earth metal alloys, magnetic susceptibility measurements for liquid Gd-NM (NM = Cu, Ga, Ge was performed by Faraday method. As the results, it was observed that the sign of paramagnetic Curie temperature of Cu-Gd alloys are positive at all composition, while Ga-Gd and Ge-Gd alloys show negative paramagnetic Curie temperature at certain composition. Moreover, it was indicated when the alloy at certain composition shows highest melting temperature, it has the lowest paramagnetic Curie temperature.

  5. TUNABLE DIODE LASER MEASUREMENTS OF NO2 NEAR 670 NM AND 395 NM. (R823933)

    Science.gov (United States)

    Two single-mode diode lasers were used to record high-resolution absorption spectra of NO2 (dilute in Ar) near 670.2 and 394.5 nm over a range of temperatures (296 to 774 K) and total pressures (2.4 x 10(-2) to 1 atm). A commercial InGaAsP laser was tuned 1.3 cm(-1) at a repetiti...

  6. Monolithic PM Raman fiber laser at 1679 nm for Raman amplification at 1810 nm

    DEFF Research Database (Denmark)

    Svane, Ask Sebastian; Rottwitt, Karsten

    2013-01-01

    Stimulated Raman scattering (SRS) has been subject to much attention within the field of fiber lasers and amplifiers as it provides an extended wavelength coverage in comparison to rare-earth based devices. Motivated by the projected capacity crunch [1], different approaches are being explored...... demonstrate a monolithic RM Raman fiber laser (RFL), which acts as a pump for a Raman amplifier (RA) at 1810 nm. The lasing wavelength of a RFL, thus also for a RA, can in principle be designed arbitrarily within the entire wavelength range from the Erbium band up to the Thulium/Holmium band...... of OFS PM Raman fiber, with an estimated propagation loss of 0.42/0.46/1.3 dB/km at 1564/1679/1810 nm. The Raman gain coefficient was measured to be gR=2.66/2.35 W-1km-1 at 1679/1810 nm. The laser curve of the RFL is depicted in Fig. 1b, with a slope efficiency of 67 %. The high slope efficiency...

  7. Particle detectors

    CERN Document Server

    Hilke, Hans Jürgen

    1992-01-01

    We shall discuss the principles of the main techniques applied to particle detection (including front-end electronics), the construction and performance of some of the devices presently in operation and a few ideas on future developments.

  8. Auroral particles

    International Nuclear Information System (INIS)

    Evans, D.S.

    1987-01-01

    The problems concerning the aurora posed prior to the war are now either solved in principle or were restated in a more fundamental form. The pre-war hypothesis concerning the nature of the auroral particles and their energies was fully confirmed, with the exception that helium and oxygen ions were identified as participating in the auroral particle precipitation in addition to the protons. The nature of the near-Earth energization processes affecting auroral particles was clarified. Charged particle trajectories in various electric field geometries were modeled. The physical problems have now moved from determining the nature and geometry of the electric fields, which accelerate charged particles near the Earth, to accounting for the existence of these electric fields as a natural consequence of the solar wind's interaction with Earth. Ultimately the reward in continuing the work in auroral and magnetospheric particle dynamics will be a deeper understanding of the subtleties of classical electricity and magnetism as applied to situations not blessed with well-defined and invariant geometries

  9. Elementary particles and particle interactions

    International Nuclear Information System (INIS)

    Bethge, K.; Schroeder, U.E.

    1986-01-01

    This book is a textbook for an introductory course of elementary particle physics. After a general introduction the symmetry principles governing the interactions of elementary particles are discussed. Then the phenomenology of the electroweak and strong interactions are described together with a short introduction to the Weinberg-Salam theory respectively to quantum chromodynamics. Finally a short outlook is given to grand unification with special regards to SU(5) and cosmology in the framework of the current understanding of the fundamental principles of nature. In the appendix is a table of particle properties and physical constants. (HSI) [de

  10. Superconducting lead particles produced by chemical techniques

    Science.gov (United States)

    Fariss, T. L.; Nixon, W. E.; Bucelot, T. J.; Deaver, B. S., Jr.; Mitchell, J. W.

    1982-09-01

    The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by ˜0.1 K.

  11. Superconducting lead particles produced by chemical techniques

    International Nuclear Information System (INIS)

    Fariss, T.L.; Nixon, W.E.; Bucelot, T.J.; Deaver, B.S. Jr.; Mitchell, J.W.

    1982-01-01

    The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by approx.0.1 K

  12. Stimulation of DNA synthesis by 340nm/ 351nm UV laser irradiation

    International Nuclear Information System (INIS)

    Meldrum, R.A.; Wharton, C.W.

    1991-01-01

    During preliminary experiments designed to test the feasibility of using a 'caged' DNA break trapping agent, the authors observed a stimulation of incorporation of 3 H-thymidine into DNA when cells were irradiated with low doses (100-1000J/m 2 ) of 351nm UV laser irradiation. This wavelength is used to photolyse 'caged' dideoxynucleotides in our fast time course measurements of DNA repair in mammalian cells. The dose at which this stimulation was observed is well below that at which measurable damage is detected. (author)

  13. Particle detectors

    CERN Document Server

    Hilke, Hans Jürgen; Joram, Christian; CERN. Geneva

    1991-01-01

    Lecture 5: Detector characteristics: ALEPH Experiment cut through the devices and events - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operartion and a few ideas on the future performance. Lecture 4-pt. b Following the Scintillators. Lecture 4-pt. a : Scintillators - Used for: -Timing (TOF, Trigger) - Energy Measurement (Calorimeters) - Tracking (Fibres) Basic scintillation processes- Inorganic Scintillators - Organic Scintil - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operation and a fiew ideas on future developpement session 3 - part. b Following Calorimeters lecture 3-pt. a Calorimeters - determine energy E by total absorption of charged or neutral particles - fraction of E is transformed into measurable quantities - try to acheive sig...

  14. Stable particles

    International Nuclear Information System (INIS)

    Samios, N.P.

    1993-01-01

    I have been asked to review the subject of stable particles, essentially the particles that eventually comprised the meson and baryon octets. with a few more additions -- with an emphasis on the contributions made by experiments utilizing the bubble chamber technique. In this activity, much work had been done by the photographic emulsion technique and cloud chambers-exposed to cosmic rays as well as accelerator based beams. In fact, many if not most of the stable particles were found by these latter two techniques, however, the forte of the bubble chamber (coupled with the newer and more powerful accelerators) was to verify, and reinforce with large statistics, the existence of these states, to find some of the more difficult ones, mainly neutrals and further to elucidate their properties, i.e., spin, parity, lifetimes, decay parameters, etc

  15. Particle physics

    CERN Document Server

    Martin, Brian R

    2017-01-01

    An accessible and carefully structured introduction to Particle Physics, including important coverage of the Higgs Boson and recent progress in neutrino physics. Fourth edition of this successful title in the Manchester Physics series. Includes information on recent key discoveries including : An account of the discovery of exotic hadrons, beyond the simple quark model; Expanded treatments of neutrino physics and CP violation in B-decays; An updated account of ‘physics beyond the standard model’, including the interaction of particle physics with cosmology; Additional problems in all chapters, with solutions to selected problems available on the book’s website; Advanced material appears in optional starred sections.

  16. Investigating Degradation Mechanisms in 130 nm and 90 nm Commercial CMOS Technologies Under Extreme Radiation Conditions

    Science.gov (United States)

    Ratti, Lodovico; Gaioni, Luigi; Manghisoni, Massimo; Traversi, Gianluca; Pantano, Devis

    2008-08-01

    The purpose of this paper is to study the mechanisms underlying performance degradation in 130 nm and 90 nm commercial CMOS technologies exposed to high doses of ionizing radiation. The investigation has been mainly focused on their noise properties in view of applications to the design of low-noise, low-power analog circuits to be operated in harsh environment. Experimental data support the hypothesis that charge trapping in shallow trench isolation (STI), besides degrading the static characteristics of interdigitated NMOS transistors, also affects their noise performances in a substantial fashion. The model discussed in this paper, presented in a previous work focused on CMOS devices irradiated with a 10 Mrad(SiO2) gamma -ray dose, has been applied here also to transistors exposed to much higher (up to 100 Mrad(SiO2 )) doses of X-rays. Such a model is able to account for the extent of the observed noise degradation as a function of the device polarity, dimensions and operating point.

  17. Distribution of lead in single atmospheric particles

    Directory of Open Access Journals (Sweden)

    D. M. Murphy

    2007-06-01

    Full Text Available Three independent single particle mass spectrometers measured Pb in individual aerosol particles. These data provide unprecedented sensitivity and statistical significance for the measurement of Pb in single particles. This paper explores the reasons for the frequency of Pb in fine particles now that most gasoline is unleaded. Trace amounts of Pb were found in 5 to 25% of 250 to 3000 nm diameter particles sampled by both aircraft and surface instruments in the eastern and western United States. Over 5% of particles at a mountain site in Switzerland contained Pb. Particles smaller than 100 nm with high Pb content were also observed by an instrument that was only operated in urban areas. Lead was found on all types of particles, including Pb present on biomass burning particles from remote fires. Less common particles with high Pb contents contributed a majority of the total amount of Pb. Single particles with high Pb content often also contained alkali metals, Zn, Cu, Sn, As, and Sb. The association of Pb with Zn and other metals is also found in IMPROVE network filter data from surface sites. Sources of airborne Pb in the United States are reviewed for consistency with these data. The frequent appearance of trace Pb is consistent with widespread emissions of fine Pb particles from combustion sources followed by coagulation with larger particles during long-range transport. Industrial sources that directly emit Pb-rich particles also contribute to the observations. Clean regions of the western United States show some transport of Pb from Asia but most Pb over the United States comes from North American sources. Resuspension of Pb from soil contaminated by the years of leaded gasoline was not directly apparent.

  18. Distribution of lead in single atmospheric particles

    Science.gov (United States)

    Murphy, D. M.; Hudson, P. K.; Cziczo, D. J.; Gallavardin, S.; Froyd, K. D.; Johnston, M. V.; Middlebrook, A. M.; Reinard, M. S.; Thomson, D. S.; Thornberry, T.; Wexler, A. S.

    2007-06-01

    Three independent single particle mass spectrometers measured Pb in individual aerosol particles. These data provide unprecedented sensitivity and statistical significance for the measurement of Pb in single particles. This paper explores the reasons for the frequency of Pb in fine particles now that most gasoline is unleaded. Trace amounts of Pb were found in 5 to 25% of 250 to 3000 nm diameter particles sampled by both aircraft and surface instruments in the eastern and western United States. Over 5% of particles at a mountain site in Switzerland contained Pb. Particles smaller than 100 nm with high Pb content were also observed by an instrument that was only operated in urban areas. Lead was found on all types of particles, including Pb present on biomass burning particles from remote fires. Less common particles with high Pb contents contributed a majority of the total amount of Pb. Single particles with high Pb content often also contained alkali metals, Zn, Cu, Sn, As, and Sb. The association of Pb with Zn and other metals is also found in IMPROVE network filter data from surface sites. Sources of airborne Pb in the United States are reviewed for consistency with these data. The frequent appearance of trace Pb is consistent with widespread emissions of fine Pb particles from combustion sources followed by coagulation with larger particles during long-range transport. Industrial sources that directly emit Pb-rich particles also contribute to the observations. Clean regions of the western United States show some transport of Pb from Asia but most Pb over the United States comes from North American sources. Resuspension of Pb from soil contaminated by the years of leaded gasoline was not directly apparent.

  19. Comparing magnetostructural transitions in Ni{sub 50}Mn{sub 18.75}Cu{sub 6.25}Ga{sub 25} and Ni{sub 49.80}Mn{sub 34.66}In{sub 15.54} Heusler alloys

    Energy Technology Data Exchange (ETDEWEB)

    Dubenko, Igor [Department of Physics, Southern Illinois University, Carbondale, IL 62901 (United States); Granovsky, Alexander [Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Lahderanta, Erkki [Lappeenranta University of Technology, 53851 (Finland); Kashirin, Maxim; Makagonov, Vladimir [Voronezh State Technical University, Voronezh 394026 (Russian Federation); Aryal, Anil; Quetz, Abdiel; Pandey, Sudip [Department of Physics, Southern Illinois University, Carbondale, IL 62901 (United States); Rodionov, Igor [Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Samanta, Tapas; Stadler, Shane [Department of Physics & Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Mazumdar, Dipanjan, E-mail: dmazumdar@siu.edu [Department of Physics, Southern Illinois University, Carbondale, IL 62901 (United States); Ali, Naushad [Department of Physics, Southern Illinois University, Carbondale, IL 62901 (United States)

    2016-03-01

    The crystal structure, magnetic and transport properties, including resistivity and thermopower, of Ni{sub 50}Mn{sub 18.75}Cu{sub 6.25}Ga{sub 25} and Ni{sub 49.80}Mn{sub 34.66}In{sub 15.54} Heusler alloys were studied in the (10–400) K temperature interval. We show that their physical properties are remarkably different, thereby pointing to different origin of their magnetostructural transition (MST). A Seebeck coefficient (S) was found to pass minimum of about −20 µV/K in respect of temperature for both compounds. It was shown that MST observed for both compounds results in jump-like changes in S for Ga-based compound and jump in resistivity of about 20 and 200 µΩ cm for Ga and In –based compounds, respectively. The combined analyzes of the present results with that from literature show that the density of states at the Fermi level does not change strongly at the MST in the case of Ni–Mn–In alloys as compared to that of Ni–Mn–Ga. - Graphical abstract: Temperature dependencies of resistivity for Ni{sub 50}Mn{sub 18.75}Cu{sub 6.25}Ga{sub 25} and Ni{sub 49.80}Mn{sub 34.66}In{sub 15.54} obtained on heating (open symbols) and cooling (closed symbols). Arrows indicate the temperature of direct (T{sub M}) and inverse (T{sub A}) martensitic transitions and ferromagnetic ordering of the austenitic (T{sub C}) and martensitic (T{sub CM}) phases. The T{sub CM}=T{sub A}/T{sub M} in the case of Ga-based alloy. - Highlights: • Magnetostructural transitions (MST) in two compounds with same parent material. • The figure exemplifies how sensitive MST properties are to the density of states. • Proper understanding is required for utilizing these multifunctional materials.

  20. Elementary particles

    International Nuclear Information System (INIS)

    Prasad, R.

    1984-01-01

    Two previous monographs report on investigations into the extent to which a unified field theory can satisfactorily describe physical reality. The first, Unified field Theory, showed that the paths within a non-Riemannian space are governed by eigenvalue equations. The second, Fundamental Constants, show that the field tensors satisfy sets of differential equations with solutions which represent the evolution of the fields along the paths of the space. The results from the first two monographs are used in this one to make progress on the theory of elementary particles. The five chapters are as follows - Quantum mechanics, gravitation and electromagnetism are aspects of the Unified theory; the fields inside the particle; the quadratic and linear theories; the calculation of the eigenvalues and elementary particles as stable configurations of interacting fields. It is shown that it is possible to construct an internal structure theory for elementary particles. The theory lies within the framework of Einstein's programme-to identify physical reality with a specified geometrical structure. (U.K.)

  1. Pinpointing particles

    International Nuclear Information System (INIS)

    Miller, David J.

    1987-01-01

    The Conference on Position-Sensitive Detectors held at London's University College from 7-11 September highlighted the importance and the growing applications of these precision devices in many branches of science, underlining once again the high spinoff potential for techniques developed inside particle physics

  2. Particle tracking

    International Nuclear Information System (INIS)

    Mais, H.; Ripken, G.; Wrulich, A.; Schmidt, F.

    1986-02-01

    After a brief description of typical applications of particle tracking in storage rings and after a short discussion of some limitations and problems related with tracking we summarize some concepts and methods developed in the qualitative theory of dynamical systems. We show how these concepts can be applied to the proton ring HERA. (orig.)

  3. Pinpointing particles

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David J.

    1987-10-15

    The Conference on Position-Sensitive Detectors held at London's University College from 7-11 September highlighted the importance and the growing applications of these precision devices in many branches of science, underlining once again the high spinoff potential for techniques developed inside particle physics.

  4. Particle Physics

    CERN Multimedia

    2005-01-01

    While biomedicine and geoscience use grids to bring together many different sub-disciplines, particle physicists use grid computing to increase computing power and storage resources, and to access and analyze vast amounts of data collected from detectors at the world's most powerful accelerators (1 page)

  5. ZnO and TiO2 particles: a study on nanosafety and photoprotection

    Science.gov (United States)

    Popov, Alexey; Zhao, Xin; Zvyagin, Andrei; Lademann, Jürgen; Roberts, Michael; Sanchez, Washington; Priezzhev, Alexander; Myllylä, Risto

    2010-04-01

    Nanoparticles of titanium dioxide (TiO2) and zinc oxide (ZnO) are used in sunscreens as protective compounds against UV radiation. We investigate these particles from the viewpoint of nanosafety (penetration into skin in vivo, production of free radicals when UV-irradiated) as well as UV protection. We show that: a) even after multiple applications, the particles remain within stratum corneum (uppermost skin layer); b) the optimal sizes are 62 nm and 45 nm, respectively for TiO2 and ZnO particles for 310-nm light and, correspondingly, 122 and 140 nm - for 400-nm radiation; c) in general, small particles (25 nm in diameter) are more photoactive than the larger ones (400 nm in diameter); however, on the background if porcine skin in vitro this difference is not seen and is substantially surpassed by skin contribution into production of free radicals.

  6. Optical breakdown threshold investigation of 1064 nm laser induced air plasmas

    International Nuclear Information System (INIS)

    Thiyagarajan, Magesh; Thompson, Shane

    2012-01-01

    classical microwave breakdown theory after correcting for the multiphoton ionization process for different pressures and good agreement, regarding both pressure dependence and breakdown threshold electric fields, is obtained. The effect of the presence of submicron particles on the 1064 nm breakdown threshold was also investigated. The measurements show that higher breakdown field is required, especially at lower pressures, and in close agreement with classical microwave breakdown theory and measurements in air.

  7. First principles study on the interfacial properties of NM/graphdiyne (NM = Pd, Pt, Rh and Ir): The implications for NM growing

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zhansheng; Li, Shuo; Lv, Peng [College of Physics and Electronic Engineering, Henan Normal University, Xinxiang 453007 (China); He, Chaozheng, E-mail: hecz2013@nynu.edu.cn [College of Physics and Electronic Engineering, Nanyang Normal University, Nanyang 473061 (China); Ma, Dongwei [School of Physics, Anyang Normal University, Anyang 455000 (China); Yang, Zongxian, E-mail: yzx@henannu.edu.cn [College of Physics and Electronic Engineering, Henan Normal University, Xinxiang 453007 (China); Collaborative Innovation Center of Nano Functional Materials and Applications, Kaifeng (China)

    2016-01-01

    Graphical abstract: - Highlights: • The NM adatoms belong to embedded adsorption in 18C-hexagon of GDY. • The Rh and Ir/GDY can be applied to single metal catalysts or sensors. • A simple linear relationship between E{sub e-ads} and E{sub b} is presented. • The linear relationship can be used in the noble metal modified GDY. - Abstract: Based on the dispersion-corrected density functional calculations (DFT-D), we systematically studied the adsorption of noble metals (NM), Pd, Pt, Rh and Ir, on graphdiyne (GDY). We present a systematic study on the geometry, embedded adsorption energy and electronic structure of four different adatoms adsorbed on the GDY. The strong interaction between the NM adatoms and the GDY substrate is found with the NM embedded in the 18C-hexagon of the GDY. We investigated the mobility of the NM adatoms on the GDY, and found that the mobility barrier energy increases along with the increasing of the embedded adsorption energy. We present the NM adatoms growth of high concentrations on the GDY. Upon the analysis of the electronic structure and the frontier molecular orbitals, Rh and Ir adatoms of low concentrations (about 1.37 at%) on the GDY have the potential to be applied as single metal catalysts or gas molecule sensors.

  8. Ultrasmooth, Highly Spherical Monocrystalline Gold Particles for Precision Plasmonics

    KAUST Repository

    Lee, You-Jin; Schade, Nicholas B.; Sun, Li; Fan, Jonathan A.; Bae, Doo Ri; Mariscal, Marcelo M.; Lee, Gaehang; Capasso, Federico; Sacanna, Stefano; Manoharan, Vinothan N.; Yi, Gi-Ra

    2013-01-01

    isotropic, so that spheres are favored under quasi-static conditions. It is scalable up to particle sizes of 200 nm or more. The resulting spherical crystals display uniform scattering spectra and consistent optical coupling at small separations, even

  9. High-yield fabrication and properties of 1.4 nm nanodiamonds with narrow size distribution.

    Science.gov (United States)

    Stehlik, Stepan; Varga, Marian; Ledinsky, Martin; Miliaieva, Daria; Kozak, Halyna; Skakalova, Viera; Mangler, Clemens; Pennycook, Timothy J; Meyer, Jannik C; Kromka, Alexander; Rezek, Bohuslav

    2016-12-02

    Detonation nanodiamonds (DNDs) with a typical size of 5 nm have attracted broad interest in science and technology. Further size reduction of DNDs would bring these nanoparticles to the molecular-size level and open new prospects for research and applications in various fields, ranging from quantum physics to biomedicine. Here we show a controllable size reduction of the DND mean size down to 1.4 nm without significant particle loss and with additional disintegration of DND core agglutinates by air annealing, leading to a significantly narrowed size distribution (±0.7 nm). This process is scalable to large quantities. Such molecular-sized DNDs keep their diamond structure and characteristic DND features as shown by Raman spectroscopy, infrared spectroscopy, STEM and EELS. The size of 1 nm is identified as a limit, below which the DNDs become amorphous.

  10. High-yield fabrication and properties of 1.4 nm nanodiamonds with narrow size distribution

    Science.gov (United States)

    Stehlik, Stepan; Varga, Marian; Ledinsky, Martin; Miliaieva, Daria; Kozak, Halyna; Skakalova, Viera; Mangler, Clemens; Pennycook, Timothy J.; Meyer, Jannik C.; Kromka, Alexander; Rezek, Bohuslav

    2016-12-01

    Detonation nanodiamonds (DNDs) with a typical size of 5 nm have attracted broad interest in science and technology. Further size reduction of DNDs would bring these nanoparticles to the molecular-size level and open new prospects for research and applications in various fields, ranging from quantum physics to biomedicine. Here we show a controllable size reduction of the DND mean size down to 1.4 nm without significant particle loss and with additional disintegration of DND core agglutinates by air annealing, leading to a significantly narrowed size distribution (±0.7 nm). This process is scalable to large quantities. Such molecular-sized DNDs keep their diamond structure and characteristic DND features as shown by Raman spectroscopy, infrared spectroscopy, STEM and EELS. The size of 1 nm is identified as a limit, below which the DNDs become amorphous.

  11. Active particles

    CERN Document Server

    Degond, Pierre; Tadmor, Eitan

    2017-01-01

    This volume collects ten surveys on the modeling, simulation, and applications of active particles using methods ranging from mathematical kinetic theory to nonequilibrium statistical mechanics. The contributing authors are leading experts working in this challenging field, and each of their chapters provides a review of the most recent results in their areas and looks ahead to future research directions. The approaches to studying active matter are presented here from many different perspectives, such as individual-based models, evolutionary games, Brownian motion, and continuum theories, as well as various combinations of these. Applications covered include biological network formation and network theory; opinion formation and social systems; control theory of sparse systems; theory and applications of mean field games; population learning; dynamics of flocking systems; vehicular traffic flow; and stochastic particles and mean field approximation. Mathematicians and other members of the scientific commu...

  12. Limitations in the Use of Unipolar Charging for Electrical Mobility Sizing Instruments: A Study of the Fast Mobility Particle Sizer

    DEFF Research Database (Denmark)

    Levin, Marcus; Gudmundsson, A.; Pagels, J. H.

    2015-01-01

    concentrations. The results show that all three sizing-instruments agree well for particle sizes below 200nm, both in terms of size and number concentration, but the FMPS deviates clearly when particle sizes exceed 200nm. Above this, the FMPS underestimates the particle size throughout the remainder of the size...

  13. UV spectroscopy of Titan's atmosphere, planetary organic chemistry and prebiological synthesis. II - Interpretation of new IUE observations in the 220-335 nm range

    Science.gov (United States)

    Courtin, Regis; Wagener, Richard; Mckay, Christopher P.; Caldwell, John; Fricke, Karl-Heinrich

    1991-01-01

    The theoretical model developed by McKay et al. (1989) to characterize the size distribution, thermal structure, and chemical composition of the stratospheric haze of Titan is applied to new 220-335-nm albedo measurements obtained with the long-wavelength prime camera of the IUE during August 1987. Data and model predictions are presented in extensive graphs and discussed in detail. It is shown that a simple model with particles of one size at a given altitude does not accurately reproduce the observed features in all spectral regions, but that good general agreement is obtained using a model with a uniformly mixed layer at 150-600 km and a bimodal distribution of small 'polymer' haze particles (radius less than 20 nm) and larger haze particles (radius 100-500 nm). The number densities implied by this model require, however, a mechanism such as electrostatic charging or reaction kinetics to inhibit coagulation of the smaller particles.

  14. Cloud condensation nuclei droplet growth kinetics of ultrafine particles during anthropogenic nucleation events

    Science.gov (United States)

    Shantz, N. C.; Pierce, J. R.; Chang, R. Y.-W.; Vlasenko, A.; Riipinen, I.; Sjostedt, S.; Slowik, J. G.; Wiebe, A.; Liggio, J.; Abbatt, J. P. D.; Leaitch, W. R.

    2012-02-01

    Evolution of the cloud condensation nucleus (CCN) activity of 36 ± 4 nm diameter anthropogenic aerosol particles at a water supersaturation of 1.0 ± 0.1% is examined for particle nucleation and growth. During the early stages of one event, relatively few of the anthropogenic particles at 36 nm were CCN active and their growth rates by water condensation were delayed relative to ammonium sulphate particles. As the event progressed, the particle size distribution evolved to larger sizes and the relative numbers of particles at 36 nm that were CCN active increased until all the 36 nm particles were activating at the end of the event. Based on the chemistry of larger particles and the results from an aerosol chemical microphysics box model, the increase in CCN activity of the particles was most likely the result of the condensation of sulphate in this case. Despite the increased CCN activity, a delay was observed in the initial growth of these particles into cloud droplets, which persisted even when the aerosol was most CCN active later in the afternoon. Simulations show that the delay in water uptake is explained by a reduction of the mass accommodation coefficient assuming that the composition of the 36 nm particles is the same as the measured composition of the 60-100 nm particles.

  15. Surgical smoke and ultrafine particles

    Directory of Open Access Journals (Sweden)

    Nowak Dennis

    2008-12-01

    Full Text Available Abstract Background Electrocautery, laser tissue ablation, and ultrasonic scalpel tissue dissection all generate a 'surgical smoke' containing ultrafine ( Methods To measure the amount of generated particulates in 'surgical smoke' during different surgical procedures and to quantify the particle number concentration for operation room personnel a condensation particle counter (CPC, model 3007, TSI Inc. was applied. Results Electro-cauterization and argon plasma tissue coagulation induced the production of very high number concentration (> 100000 cm-3 of particles in the diameter range of 10 nm to 1 μm. The peak concentration was confined to the immediate local surrounding of the production side. In the presence of a very efficient air conditioning system the increment and decrement of ultrafine particle occurrence was a matter of seconds, with accumulation of lower particle number concentrations in the operation room for only a few minutes. Conclusion Our investigation showed a short term very high exposure to ultrafine particles for surgeons and close assisting operating personnel – alternating with longer periods of low exposure.

  16. Acute and Cumulative Effects of Unmodified 50-nm Nano-ZnO on Mice.

    Science.gov (United States)

    Kong, Tao; Zhang, Shu-Hui; Zhang, Ji-Liang; Hao, Xue-Qin; Yang, Fan; Zhang, Cai; Yang, Zi-Jun; Zhang, Meng-Yu; Wang, Jie

    2018-01-02

    Nanometer zinc oxide (nano-ZnO) is widely used in diverse industrial and agricultural fields. Due to the extensive contact humans have with these particles, it is crucial to understand the potential effects that nano-ZnO have on human health. Currently, information related to the toxicity and mechanisms of nano-ZnO is limited. The aim of the present study was to investigate acute and cumulative toxic effects of 50-nm unmodified ZnO in mice. This investigation will seek to establish median lethal dose (LD50), a cumulative coefficient, and target organs. The acute and cumulative toxicity was investigated by Karber's method and via a dose-increasing method, respectively. During the experiment, clinical signs, mortality, body weights, hematology, serum biochemistry, gross pathology, organ weight, and histopathology were examined. The LD50 was 5177-mg/kg·bw; the 95% confidence limits for the LD50 were 5116-5238-mg/kg·bw. It could be concluded that the liver, kidney, lung, and gastrointestinal tract were target organs for the 50-nm nano-ZnO acute oral treatment. The cumulative coefficient (K) was 1.9 which indicated that the cumulative toxicity was apparent. The results also indicated that the liver, kidney, lung, and pancrea were target organs for 50-nm nano-ZnO cumulative oral exposure and might be target organs for subchronic and chronic toxicity of oral administered 50-nm ZnO.

  17. Hot particles

    International Nuclear Information System (INIS)

    Merwin, S.E.; Moeller, M.P.

    1989-01-01

    Nuclear Regulatory Commission (NRC) licensees are required to assess the dose to skin from a hot particle contamination event at a depth of skin of7mg/cm 2 over an area of 1 cm 2 and compare the value to the current dose limit for the skin. Although the resulting number is interesting from a comparative standpoint and can be used to predict local skin reactions, comparison of the number to existing limits based on uniform exposures is inappropriate. Most incidents that can be classified as overexposures based on this interpretation of dose actually have no effect on the health of the worker. As a result, resources are expended to reduce the likelihood that an overexposure event will occur when they could be directed toward eliminating the cause of the problem or enhancing existing programs such as contamination control. Furthermore, from a risk standpoint, this practice is not ALARA because some workers receive whole body doses in order to minimize the occurrence of hot particle skin contaminations. In this paper the authors suggest an alternative approach to controlling hot particle exposures

  18. High-efficency stable 213-nm generation for LASIK application

    Science.gov (United States)

    Wang, Zhenglin; Alameh, Kamal; Zheng, Rong

    2005-01-01

    213nm Solid-state laser technology provides an alternative method to replace toxic excimer laser in LASIK system. In this paper, we report a compact fifth harmonic generation system to generate high pulse energy 213nm laser from Q-switched Nd:YAG laser for LASIK application based on three stages harmonic generation procedures. A novel crystal housing was specifically designed to hold the three crystals with each crystal has independent, precise angular adjustment structure and automatic tuning control. The crystal temperature is well maintained at ~130°C to improve harmonic generation stability and crystal operation lifetime. An output pulse energy 35mJ is obtained at 213nm, corresponding to total conversion efficiency ~10% from 1064nm pump laser. In system verification tests, the 213nm output power drops less than 5% after 5 millions pulse shots and no significant damage appears in the crystals.

  19. Thin film and multilayer optics for XUV spectral domain (1 nm to 60 nm)

    International Nuclear Information System (INIS)

    Delmotte, Franck

    2010-02-01

    The XUV spectral domain (1-60 nm wavelength range) has experienced rapid growth in recent years. On one side, the sources (synchrotron radiation, harmonic generation, x-ray laser, free-electron laser...) require ever more efficient optics, on the other hand, applications (diagnostics of hot plasma, solar physics, x-ray microscopy, EUV lithography, x-ray analysis...) provide new constraints on the design of multilayer stacks. The multilayer mirrors are the only way to achieve efficient optics operating at non-grazing incidence angles in this spectral range. Our work within the team XUV Optics at Laboratoire Charles Fabry de l'Institut d'Optique focuses on the study of materials in thin layers correlated to the study of optical properties of multilayers. The objective is to achieve new multilayer components previously unavailable in the XUV domain, through a better understanding of physical phenomena in these nano-layer stacks. We show through several examples of how we have managed both to improve the performance of multilayer mirrors in a broad spectral range, and secondly, to develop new optical functions: beam splitters, broadband mirrors, dual-band mirrors or phase compensation mirrors. (author)

  20. Picosecond laser texturization of mc-silicon for photovoltaics: A comparison between 1064 nm, 532 nm and 355 nm radiation wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Binetti, Simona [Department of Materials Science and Milano-Bicocca Solar Energy Research Center (MIB-SOLAR), University of Milano-Bicocca, Via Cozzi 55, 20125 Milano (Italy); Le Donne, Alessia, E-mail: alessia.ledonne@mater.unimib.it [Department of Materials Science and Milano-Bicocca Solar Energy Research Center (MIB-SOLAR), University of Milano-Bicocca, Via Cozzi 55, 20125 Milano (Italy); Rolfi, Andrea [Department of Materials Science and Milano-Bicocca Solar Energy Research Center (MIB-SOLAR), University of Milano-Bicocca, Via Cozzi 55, 20125 Milano (Italy); Jäggi, Beat; Neuenschwander, Beat [Bern University of Applied Sciences, Engineering and Information Technology, Institute for Applied Laser, Photonics and Surface Technologies ALPS, Pestalozzistrasse 20, CH-3400 Burgdorf (Switzerland); Busto, Chiara [ENI Spa, Via Giacomo Fauser, 4, 28100 Novara (Italy); Frigeri, Cesare [CNR-IMEM Institute, Parco Area Delle Scienze 37/A, Fontanini, 43010 Parma (Italy); Scorticati, Davide; Longoni, Luca; Pellegrino, Sergio [Laserpoint Srl, Via Della Burrona 51, 20090 Vimodrone, Milano (Italy)

    2016-05-15

    Highlights: • Self-organized surface structures were produced by picosecond laser pulses on mc-Si. • Three laser wavelengths were used which effectively reduce Si reflectivity up to 8%. • The subsurface damage induced by the three lasers was studied in detail. • μ-Raman, PL and TEM proved that UV laser provides the lowest subsurface damage. • UV laser induced damage is located above the depletion region of the p–n junction. - Abstract: Self-organized surface structures were produced by picosecond laser pulses on multi-crystalline silicon for photovoltaic applications. Three different laser wavelengths were employed (i.e. 1064 nm, 532 nm and 355 nm) and the resulting morphologies were observed to effectively reduce the reflectivity of the samples after laser irradiation. Besides, a comparative study of the laser induced subsurface damage generated by the three different wavelengths was performed by confocal micro-Raman, photoluminescence and transmission electron microscopy. The results of both the structural and optical characterization showed that the mc-Si texturing performed with the laser at 355 nm provides surface reflectivity between 11% and 8% over the spectral range from 400 nm to 1 μm, while inducing the lowest subsurface damage, located above the depletion region of the p–n junction.

  1. New particles

    Energy Technology Data Exchange (ETDEWEB)

    Khare, A.

    1980-07-01

    Current state of art in the discovery of new elementary particles is reviewed. At present, quarks and mesons are accepted as the basic constituents of matter. The charmonium model (canti-c system), and the 'open charm' are discussed. Explanations are offered for the recent discovery of the heavy lepton tau. Quark states such as the beauty and taste are also dealt with at length. The properties of the tanti-t bound system are speculated. It is concluded that the understanding of canti-c and banti-b families is facilitated by the assumption of the quarkonium model. Implications at the astrophysical level are indicated.

  2. Particle Mechanics

    CERN Document Server

    Collinson, Chris

    1995-01-01

    * Assumes no prior knowledge* Adopts a modelling approach* Numerous tutorial problems, worked examples and exercises included* Elementary topics augmented by planetary motion and rotating framesThis text provides an invaluable introduction to mechanicsm confining attention to the motion of a particle. It begins with a full discussion of the foundations of the subject within the context of mathematical modelling before covering more advanced topics including the theory of planetary orbits and the use of rotating frames of reference. Truly introductory , the style adoped is perfect for those u

  3. Development of 2-channel (532 nm and 355 nm) mobile LIDAR for mapping particulate matter in the atmosphere

    CSIR Research Space (South Africa)

    Sivakumar, V

    2010-09-01

    Full Text Available In this paper, the authors describe the developmentof 2-Channel (532 nm and 355 nm) mobile LIDAR system for studying atmospheric particulate matter. The system is currently tested in house at the Council for Scientific and Industrial Research...

  4. Wavelength dependence on the forensic analysis of glass by nanosecond 266 nm and 1064 nm laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cahoon, Erica M.; Almirall, Jose R.

    2010-05-01

    Laser induced breakdown spectroscopy can be used for the chemical characterization of glass to provide evidence of an association between a fragment found at a crime scene to a source of glass of known origin. Two different laser irradiances, 266 nm and 1064 nm, were used to conduct qualitative and quantitative analysis of glass standards. Single-pulse and double-pulse configurations and lens-to-sample-distance settings were optimized to yield the best laser-glass coupling. Laser energy and acquisition timing delays were also optimized to result in the highest signal-to-noise ratio corresponding to the highest precision and accuracy. The crater morphology was examined and the mass removed was calculated for both the 266 nm and 1064 nm irradiations. The analytical figures of merit suggest that the 266 nm and 1064 nm wavelengths are capable of good performance for the forensic chemical characterization of glass. The results presented here suggest that the 266 nm laser produces a better laser-glass matrix coupling, resulting in a better stoichiometric representation of the glass sample. The 266 nm irradiance is therefore recommended for the forensic analysis and comparison of glass samples.

  5. Wavelength dependence on the forensic analysis of glass by nanosecond 266 nm and 1064 nm laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Cahoon, Erica M.; Almirall, Jose R.

    2010-01-01

    Laser induced breakdown spectroscopy can be used for the chemical characterization of glass to provide evidence of an association between a fragment found at a crime scene to a source of glass of known origin. Two different laser irradiances, 266 nm and 1064 nm, were used to conduct qualitative and quantitative analysis of glass standards. Single-pulse and double-pulse configurations and lens-to-sample-distance settings were optimized to yield the best laser-glass coupling. Laser energy and acquisition timing delays were also optimized to result in the highest signal-to-noise ratio corresponding to the highest precision and accuracy. The crater morphology was examined and the mass removed was calculated for both the 266 nm and 1064 nm irradiations. The analytical figures of merit suggest that the 266 nm and 1064 nm wavelengths are capable of good performance for the forensic chemical characterization of glass. The results presented here suggest that the 266 nm laser produces a better laser-glass matrix coupling, resulting in a better stoichiometric representation of the glass sample. The 266 nm irradiance is therefore recommended for the forensic analysis and comparison of glass samples.

  6. Response of cloud condensation nuclei (>50 nm) to changes in ion-nucleation

    DEFF Research Database (Denmark)

    Svensmark, Henrik; Enghoff, Martin Andreas Bødker; Pedersen, Jens Olaf Pepke

    2013-01-01

    In experiments where ultraviolet light produces aerosols from trace amounts of ozone, sulfur dioxide, and water vapor, the relative increase in aerosols produced by ionization by gamma sources is constant from nucleation to diameters larger than 50 nm, appropriate for cloud condensation nuclei....... This result contradicts both ion-free control experiments and also theoretical models that predict a decline in the response at larger particle sizes. This unpredicted experimental finding points to a process not included in current theoretical models, possibly an ion-induced formation of sulfuric acid...

  7. Particle growth kinetics over the Amazon rainforest

    Science.gov (United States)

    Pinterich, T.; Andreae, M. O.; Artaxo, P.; Kuang, C.; Longo, K.; Machado, L.; Manzi, A. O.; Martin, S. T.; Mei, F.; Pöhlker, C.; Pöhlker, M. L.; Poeschl, U.; Shilling, J. E.; Shiraiwa, M.; Tomlinson, J. M.; Zaveri, R. A.; Wang, J.

    2016-12-01

    Aerosol particles larger than 100 nm play a key role in global climate by acting as cloud condensation nuclei (CCN). Most of these particles, originated from new particle formation or directly emitted into the atmospheric, are initially too small to serve as CCN. These small particles grow to CCN size mainly through condensation of secondary species. In one extreme, the growth is dictated by kinetic condensation of very low-volatility compounds, favoring the growth of the smallest particles; in the other extreme, the process is driven by Raoult's law-based equilibrium partitioning of semi-volatile organic compound, favoring the growth of larger particles. These two mechanisms can lead to very different production rates of CCN. The growth of particles depends on a number of parameters, including the volatility of condensing species, particle phase, and diffusivity inside the particles, and this process is not well understood in part due to lack of ambient data. Here we examine atmospheric particle growth using high-resolution size distributions measured onboard the DOE G-1 aircraft during GoAmazon campaign, which took place from January 2014 to December 2015 near Manaus, Brazil, a city surrounded by natural forest for over 1000 km in every direction. City plumes are clearly identified by the strong enhancement of nucleation and Aitken mode particle concentrations over the clean background. As the plume traveled downwind, particle growth was observed, and is attributed to condensation of secondary species and coagulation (Fig.1). Observed aerosol growth is modeled using MOSAIC (Model for Simulating Aerosol Interactions and Chemistry), which dynamically partitions multiple compounds to all particle size bins by taking into account compound volatility, gas-phase diffusion, interfacial mass accommodation, particle-phase diffusion, and particle-phase reaction. The results from both wet and dry seasons will be discussed.

  8. Histologic evaluation of laser lipolysis: pulsed 1064-nm Nd:YAG laser versus cw 980-nm diode laser.

    Science.gov (United States)

    Mordon, Serge; Eymard-Maurin, Anne Françoise; Wassmer, Benjamin; Ringot, Jean

    2007-01-01

    The use of the laser as an auxiliary tool has refined the traditional technique for lipoplasty. During laser lipolysis, the interaction between the laser and the fat produced direct cellular destruction before the suction, reduced bleeding, and promoted skin tightening. This study sought to perform a comparative histologic evaluation of laser lipolysis with the pulsed 1064-nm Nd:YAG laser versus a continuous 980-nm diode laser. A pulsed 1064-nm Nd:YAG (Smart-Lipo; Deka, Italy) and a CW 980-nm diode laser (Pharaon, Osyris, France) were evaluated at different energy settings for lipolysis on the thighs of a fresh cadaver. The lasers were coupled to a 600-microm optical fiber inserted in a 1-mm diameter cannula. Biopsy specimens were taken on irradiated and non-irradiated areas. Hematoxylin-erythrosin-safran staining and immunostaining (anti-PS100 polyclonal antibody) were performed to identify fat tissue damage. In the absence of laser exposures (control specimens), cavities created by cannulation were seen; adipocytes were round in appearance and not deflated. At low energy settings, tumescent adipocytes were observed. At higher energy settings, cytoplasmic retraction, disruption of membranes, and heat-coagulated collagen fibers were noted; coagulated blood cells were also present. For the highest energy settings, carbonization of fat tissue involving fibers and membranes was clearly seen. For equivalent energy settings, 1064-nm and 980-nm wavelengths gave similar histologic results. Laser lipolysis is a relatively new technique that is still under development. Our histologic findings suggest several positive benefits of the laser, including skin retraction and a reduction in intraoperative bleeding. The interaction of the laser with the tissue is similar at 980 nm and 1064 nm with the same energy settings. Because higher volumes of fat are removed with higher total energy, a high-power 980-nm diode laser could offer an interesting alternative to the 1064-nm Nd

  9. Ion generation and CPC detection efficiency studies in sub 3-nm size range

    Energy Technology Data Exchange (ETDEWEB)

    Kangasluoma, J.; Junninen, H.; Sipilae, M.; Kulmala, M.; Petaejae, T. [Department of Physics, P.O. Box 64, 00014, University of Helsinki, Helsinki (Finland); Lehtipalo, K. [Department of Physics, P.O. Box 64, 00014, University of Helsinki, Helsinki (Finland); Airmodus Ltd., Finland, Gustaf Haellstroemin katu 2 A, 00560 Helsinki (Finland); Mikkilae, J.; Vanhanen, J. [Airmodus Ltd., Finland, Gustaf Haellstroemin katu 2 A, 00560 Helsinki (Finland); Attoui, M. [University Paris Est Creteil, University Paris-Diderot, LISA, UMR CNRS 7583 (France); Worsnop, D. [Department of Physics, P.O. Box 64, 00014, University of Helsinki, Helsinki (Finland) and Aerodyne Research Inc., Billerica, MA (United States)

    2013-05-24

    We studied the chemical composition of commonly used condensation particle counter calibration ions with a mass spectrometer and found that in our calibration setup the negatively charged ammonium sulphate, sodium chloride and tungsten oxide are the least contaminated whereas silver on both positive and negative and the three mentioned earlier in positive mode are contaminated with organics. We report cut-off diameters for Airmodus Particle Size Magnifier (PSM) 1.1, 1.3, 1.4, 1.6 and 1.6-1.8 nm for negative sodium chloride, ammonium sulphate, tungsten oxide, silver and positive organics, respectively. To study the effect of sample relative humidity on detection efficiency of the PSM we used different humidities in the differential mobility analyzer sheath flow and found that with increasing relative humidity also the detection efficiency of the PSM increases.

  10. Ion generation and CPC detection efficiency studies in sub 3-nm size range

    International Nuclear Information System (INIS)

    Kangasluoma, J.; Junninen, H.; Sipilä, M.; Kulmala, M.; Petäjä, T.; Lehtipalo, K.; Mikkilä, J.; Vanhanen, J.; Attoui, M.; Worsnop, D.

    2013-01-01

    We studied the chemical composition of commonly used condensation particle counter calibration ions with a mass spectrometer and found that in our calibration setup the negatively charged ammonium sulphate, sodium chloride and tungsten oxide are the least contaminated whereas silver on both positive and negative and the three mentioned earlier in positive mode are contaminated with organics. We report cut-off diameters for Airmodus Particle Size Magnifier (PSM) 1.1, 1.3, 1.4, 1.6 and 1.6-1.8 nm for negative sodium chloride, ammonium sulphate, tungsten oxide, silver and positive organics, respectively. To study the effect of sample relative humidity on detection efficiency of the PSM we used different humidities in the differential mobility analyzer sheath flow and found that with increasing relative humidity also the detection efficiency of the PSM increases.

  11. Tapered diode laser pumped 946 nm Nd:YAG laser

    DEFF Research Database (Denmark)

    Cheng, Haynes Pak Hay; Jensen, Ole Bjarlin; Petersen, Paul Michael

    2009-01-01

    We successfully implemented a 946 nm Nd:YAG laser based on a 808 nm tapered diode pump laser. The tapered diode is developed at the Ferdinand-Braun-Institute fur Hochstfrequenztechnik in Germany. Figure 2 shows the experimental setup and results of each pump source coupled into a 1.5 mm crystal...... laser, we show that tapered diode laser pumping potentially increase the power of 946 nm lasers by a factor of two and reduce the threshold by a factor of three....

  12. Particle agglomeration and properties of nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    Yang Yijun; Oztekin, Alparslan, E-mail: alo2@lehigh.edu; Neti, Sudhakar [Lehigh University, Department of Mechanical Engineering and Mechanics (United States); Mohapatra, Satish [Dynalene Inc. (United States)

    2012-05-15

    The present study demonstrates the importance of actual agglomerated particle size in the nanofluid and its effect on the fluid properties. The current work deals with 5 to 100 nm nanoparticles dispersed in fluids that resulted in 200 to 800 nm agglomerates. Particle size distributions for a range of nanofluids are measured by dynamic light scattering (DLS). Wet scanning electron microscopy method is used to visualize agglomerated particles in the dispersed state and to confirm particle size measurements by DLS. Our results show that a combination of base fluid chemistry and nanoparticle type is very important to create stable nanofluids. Several nanofluids resulted in stable state without any stabilizers, but in the long term had agglomerations of 250 % over a 2 month period. The effects of agglomeration on the thermal and rheological properties are presented for several types of nanoparticle and base fluid chemistries. Despite using nanodiamond particles with high thermal conductivity and a very sensitive laser flash thermal conductivity measurement technique, no anomalous increases of thermal conductivity was measured. The thermal conductivity increases of nanofluid with the particle concentration are as those predicted by Maxwell and Bruggeman models. The level of agglomeration of nanoparticles hardly influenced the thermal conductivity of the nanofluid. The viscosity of nanofluids increased strongly as the concentration of particle is increased; it displays shear thinning and is a strong function of the level of agglomeration. The viscosity increase is significantly above of that predicted by the Einstein model even for very small concentration of nanoparticles.

  13. Particle agglomeration and properties of nanofluids

    International Nuclear Information System (INIS)

    Yang Yijun; Oztekin, Alparslan; Neti, Sudhakar; Mohapatra, Satish

    2012-01-01

    The present study demonstrates the importance of actual agglomerated particle size in the nanofluid and its effect on the fluid properties. The current work deals with 5 to 100 nm nanoparticles dispersed in fluids that resulted in 200 to 800 nm agglomerates. Particle size distributions for a range of nanofluids are measured by dynamic light scattering (DLS). Wet scanning electron microscopy method is used to visualize agglomerated particles in the dispersed state and to confirm particle size measurements by DLS. Our results show that a combination of base fluid chemistry and nanoparticle type is very important to create stable nanofluids. Several nanofluids resulted in stable state without any stabilizers, but in the long term had agglomerations of 250 % over a 2 month period. The effects of agglomeration on the thermal and rheological properties are presented for several types of nanoparticle and base fluid chemistries. Despite using nanodiamond particles with high thermal conductivity and a very sensitive laser flash thermal conductivity measurement technique, no anomalous increases of thermal conductivity was measured. The thermal conductivity increases of nanofluid with the particle concentration are as those predicted by Maxwell and Bruggeman models. The level of agglomeration of nanoparticles hardly influenced the thermal conductivity of the nanofluid. The viscosity of nanofluids increased strongly as the concentration of particle is increased; it displays shear thinning and is a strong function of the level of agglomeration. The viscosity increase is significantly above of that predicted by the Einstein model even for very small concentration of nanoparticles.

  14. Nanoparticle growth by particle-phase chemistry

    Science.gov (United States)

    Apsokardu, Michael J.; Johnston, Murray V.

    2018-02-01

    The ability of particle-phase chemistry to alter the molecular composition and enhance the growth rate of nanoparticles in the 2-100 nm diameter range is investigated through the use of a kinetic growth model. The molecular components included are sulfuric acid, ammonia, water, a non-volatile organic compound, and a semi-volatile organic compound. Molecular composition and growth rate are compared for particles that grow by partitioning alone vs. those that grow by a combination of partitioning and an accretion reaction in the particle phase between two organic molecules. Particle-phase chemistry causes a change in molecular composition that is particle diameter dependent, and when the reaction involves semi-volatile molecules, the particles grow faster than by partitioning alone. These effects are most pronounced for particles larger than about 20 nm in diameter. The modeling results provide a fundamental basis for understanding recent experimental measurements of the molecular composition of secondary organic aerosol showing that accretion reaction product formation increases linearly with increasing aerosol volume-to-surface-area. They also allow initial estimates of the reaction rate constants for these systems. For secondary aerosol produced by either OH oxidation of the cyclic dimethylsiloxane (D5) or ozonolysis of β-pinene, oligomerization rate constants on the order of 10-3 to 10-1 M-1 s-1 are needed to explain the experimental results. These values are consistent with previously measured rate constants for reactions of hydroperoxides and/or peroxyacids in the condensed phase.

  15. Northern Edge Navajo Casino, Fruitland, NM: NN0030343

    Science.gov (United States)

    NPDES Permit and Fact Sheet explaining EPA's action under the Clean Water Act to issue NPDES Permit No. NN0030343) to the Navajo Tribal Utility Authority Northern Edge Navajo Casino Wastewater Treatment Facility, 2752 Indian Service Road 36, Fruitland, NM.

  16. Compact 2050 nm Semiconductor Diode Laser Master Oscillator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I effort seeks to develop DFB laser master oscillators at the novel wavelength of 12050 nm. Two prototypes will be built, tested, and delivered ....

  17. Transcanalicular laser dacryocystorhinostomy using low energy 810 nm diode laser

    Directory of Open Access Journals (Sweden)

    Sanjiv K Gupta

    2012-01-01

    Conclusions: Transcanalicular Laser DCR can be safely performed using a low power 810 nm diode laser. The surgery is elegant, minimally invasive, allows fast rehabilitation, and has an excellent success rate.

  18. Photorefractive effect at 775 nm in doped lithium niobate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Nava, G.; Minzioni, P.; Cristiani, I.; Degiorgio, V. [Department of Electrical, Computer, and Biomedical Engineering, and CNISM, University of Pavia, 27100 Pavia (Italy); Argiolas, N.; Bazzan, M.; Ciampolillo, M. V.; Pozza, G.; Sada, C. [Physics and Astronomy Departement, University of Padova, 35131 Padova (Italy)

    2013-07-15

    The photorefractive effect induced by 775-nm laser light on doped lithium niobate crystals is investigated by the direct observation in the far field of the transmitted-beam distortion as a function of time. Measurements performed at various Zr-doping concentrations and different light intensities show that the 775-nm light beam induces a steady-state photorefractive effect comparable to that of 532-nm light, but the observed build-up time of the photovoltaic field is longer by three-orders of magnitude. The 775-nm photorefractivity of lithium niobate crystals doped with 3 mol. % ZrO{sub 2} or with 5.5 mol. % MgO is found to be negligible.

  19. Removing foxing stains from old paper at 157 nm

    International Nuclear Information System (INIS)

    Sarantopoulou, E.; Samardzija, Z.; Kobe, S.; Kollia, Z.; Cefalas, A.C.

    2003-01-01

    Using a molecular fluorine laser at 157 nm foxing stains were removed successfully from a 16th century old paper. Laser cleaning of stains and foxing from old paper manuscripts is far more effective at 157 nm in comparison to different wavelengths without leaving any yellowish after-effect on the paper. This is because at 157 nm illumination of old paper, complete bond breaking of all the organic molecules of the paper is taking place. Mass spectroscopy at 157 nm and for moderate laser intensities up to 1 mJ/cm 2 of old paper suffering from foxing indicate organic matter disintegration to small photofragments atomic, diatomic or triatomic, which are flying apart with supersonic speed. In addition high spatial resolution energy dispersive X-ray system (EDXS) analysis over the effected areas indicate the presence of iron, suggesting that biological activity is taking place preferentially in paper areas containing iron

  20. Polybutadiene latex particle size distribution analysis utilizing a disk centrifuge

    NARCIS (Netherlands)

    Verdurmen, E.M.F.J.; Albers, J.G.; German, A.L.

    1994-01-01

    Polybutadiene (I) latexes prepd. by emulsifier-free emulsion polymn. and having particle diam. 50-300 nm for both unimodal and bimodal particles size distributions were analyzed by the line-start (LIST) method in a Brookhaven disk centrifuge photosedimentometer. A special spin fluid was designed to

  1. Dynamics of individual magnetic particles near a biosensor surface

    NARCIS (Netherlands)

    van Ommering, K.

    2010-01-01

    The use of magnetic particles in biosensing is advantageous for transport of target molecules in the device, for assay integration, and for labeled detection. The particles generally have a size between 100 nm and 3 ¿m and are of a superparamagnetic nature, being composed of thousands of iron oxide

  2. Nanoparticle production by UV irradiation of combustion generated soot particles

    International Nuclear Information System (INIS)

    Stipe, Christopher B.; Choi, Jong Hyun; Lucas, Donald; Koshland, Catherine P.; Sawyer, Robert F.

    2004-01-01

    Laser ablation of surfaces normally produce high temperature plasmas that are difficult to control. By irradiating small particles in the gas phase, we can better control the size and concentration of the resulting particles when different materials are photofragmented. Here, we irradiate soot with 193 nm light from an ArF excimer laser. Irradiating the original agglomerated particles at fluences ranging from 0.07 to 0.26 J/cm 2 with repetition rates of 20 and 100 Hz produces a large number of small, unagglomerated particles, and a smaller number of spherical agglomerated particles. Mean particle diameters from 20 to 50 nm are produced from soot originally having a mean electric mobility diameter of 265nm. We use a non-dimensional parameter, called the photon/atom ratio (PAR), to aid in understanding the photofragmentation process. This parameter is the ratio of the number of photons striking the soot particles to the number of the carbon atoms contained in the soot particles, and is a better metric than the laser fluence for analyzing laser-particle interactions. These results suggest that UV photofragmentation can be effective in controlling particle size and morphology, and can be a useful diagnostic for studying elements of the laser ablation process

  3. Fermilab | Particle Physics Division

    Science.gov (United States)

    Diversity Education Safety Sustainability and Environment Contact Science Science Particle Physics Neutrinos Scientific Computing Research & Development Key Discoveries Benefits of Particle Physics Particle Superconducting Test Accelerator LHC and Future Accelerators Accelerators for Science and Society Particle Physics

  4. Investigations of a Dual Seeded 1178 nm Raman Laser System

    Science.gov (United States)

    2016-01-14

    was obtained by Raman amplification of a distributed feedback diode laser in a variably strained polarization- maintaining fiber with a record-high...Calia, D.B., “50W CW visible laser source at 589 nm obtained via frequency doubling of three coherently combined narrow-band Raman fiber amplifiers...AFRL-RD-PS- TP-2016-0009 AFRL-RD-PS- TP-2016-0009 INVESTIGATIONS OF A DUAL SEEDED 1178 NM RAMAN LASER SYSTEM Leanne Henry, et al. 14 January

  5. Clock Gating Based Energy Efficient and Thermal Aware Design for Vedic Equation Solver on 28nm and 40nm FPGA

    DEFF Research Database (Denmark)

    Pandey, Bishwajeet; Pandey, Sujeet; Sharma, Shivani

    2016-01-01

    In this paper, we are integrating clock gating in design of energy efficient equation solver circuits based on Vedic mathematics. Clock gating is one of the best energy efficient techniques. The Sutra 'SunyamSamyasamuccaye' says thatif sum of numerator and sum of denominator is same then we can e......, 94.54% for 1800MHz, and 94.02% for 2.2GHz, when we use gated clock instead of un gated one on 40nm FPGA and temperature is 329.85K. Power consumption in 28nm FPGA is less than 40nm FPGA....

  6. Power scaling of laser diode pumped Pr3+:LiYF4 cw lasers: efficient laser operation at 522.6 nm, 545.9 nm, 607.2 nm, and 639.5 nm.

    Science.gov (United States)

    Gün, Teoman; Metz, Philip; Huber, Günter

    2011-03-15

    We report efficient cw laser operation of laser diode pumped Pr(3+)-doped LiYF4 crystals in the visible spectral region. Using two InGaN laser diodes emitting at λ(P)=443.9 nm with maximum output power of 1 W each and a 2.9-mm-long crystal with a doping concentration of 0.5%, output powers of 938 mW, 418 mW, 384 mW, and 773 mW were achieved for the laser wavelengths 639.5 nm, 607.2 nm, 545.9 nm, and 522.6 nm, respectively. The maximum absorbed pump powers were approximately 1.5 W, resulting in slope efficiencies of 63.6%, 32.0%, 52.1%, and 61.5%, as well as electro-optical efficiencies of 9.4%, 4.2%, 3.8%, and 7.7%, respectively. Within these experiments, laser diode-pumped laser action at 545.9 nm was demonstrated for what is believed to be the first time.

  7. Trends in nanosecond melanosome microcavitation up to 1540 nm

    Science.gov (United States)

    Schmidt, Morgan S.; Kennedy, Paul K.; Noojin, Gary D.; Vincelette, Rebecca L.; Thomas, Robert J.; Rockwell, Benjamin A.

    2015-09-01

    Thresholds for microcavitation of bovine and porcine melanosomes were previously reported, using single nanosecond (ns) laser pulses in the visible (532 nm) and the near-infrared (NIR) from 1000 to 1319 nm. Here, we report average radiant exposure thresholds for bovine melanosome microcavitation at additional NIR wavelengths up to 1540 nm, which range from ˜0.159 J/cm2 at 800 nm to 4.5 J/cm2 at 1540 nm. Melanosome absorption coefficients were also estimated, and decreased with increasing wavelength. These values were compared to retinal pigment epithelium coefficients, and to water absorption, over the same wavelength range. Corneal total intraocular energy retinal damage threshold values were estimated and compared to the previous (2007) and recently changed (2014) maximum permissible exposure (MPE) safe levels. Results provide additional data that support the recent changes to the MPE levels, as well as the first microcavitation data at 1540 nm, a wavelength for which melanosome microcavitation may be an ns-pulse skin damage mechanism.

  8. Quantifying the motion of magnetic particles in excised tissue: Effect of particle properties and applied magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, Sandip, E-mail: sandip.d.kulkarni@gmail.com [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Ramaswamy, Bharath; Horton, Emily; Gangapuram, Sruthi [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Nacev, Alek [Weinberg Medical Physics, LLC (United States); Depireux, Didier [The Institute for Systems Research, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States); Shimoji, Mika [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States); Shapiro, Benjamin [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); The Institute for Systems Research, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States)

    2015-11-01

    This article presents a method to investigate how magnetic particle characteristics affect their motion inside tissues under the influence of an applied magnetic field. Particles are placed on top of freshly excised tissue samples, a calibrated magnetic field is applied by a magnet underneath each tissue sample, and we image and quantify particle penetration depth by quantitative metrics to assess how particle sizes, their surface coatings, and tissue resistance affect particle motion. Using this method, we tested available fluorescent particles from Chemicell of four sizes (100 nm, 300 nm, 500 nm, and 1 μm diameter) with four different coatings (starch, chitosan, lipid, and PEG/P) and quantified their motion through freshly excised rat liver, kidney, and brain tissues. In broad terms, we found that the applied magnetic field moved chitosan particles most effectively through all three tissue types (as compared to starch, lipid, and PEG/P coated particles). However, the relationship between particle properties and their resulting motion was found to be complex. Hence, it will likely require substantial further study to elucidate the nuances of transport mechanisms and to select and engineer optimal particle properties to enable the most effective transport through various tissue types under applied magnetic fields.

  9. Rapid microwave-assisted synthesis of sub-30nm lipid nanoparticles.

    Science.gov (United States)

    Dunn, Stuart S; Beckford Vera, Denis R; Benhabbour, S Rahima; Parrott, Matthew C

    2017-02-15

    Accessing the phase inversion temperature by microwave heating may enable the rapid synthesis of small lipid nanoparticles. Nanoparticle formulations consisted of surfactants Brij 78 and Vitamin E TPGS, and trilaurin, trimyristin, or miglyol 812 as nanoparticle lipid cores. Each formulation was placed in water and heated by microwave irradiation at temperatures ranging from 65°C to 245°C. We observed a phase inversion temperature (PIT) for these formulations based on a dramatic decrease in particle Z-average diameters. Subsequently, nanoparticles were manufactured above and below the PIT and studied for (a) stability toward dilution, (b) stability over time, (c) fabrication as a function of reaction time, and (d) transmittance of lipid nanoparticle dispersions. Lipid-based nanoparticles with distinct sizes down to 20-30nm and low polydispersity could be attained by a simple, one-pot microwave synthesis. This was carried out by accessing the phase inversion temperature using microwave heating. Nanoparticles could be synthesized in just one minute and select compositions demonstrated high stability. The notable stability of these particles may be explained by the combination of van der Waals interactions and steric repulsion. 20-30nm nanoparticles were found to be optically transparent. Published by Elsevier Inc.

  10. Continental anthropogenic primary particle number emissions

    Science.gov (United States)

    Paasonen, Pauli; Kupiainen, Kaarle; Klimont, Zbigniew; Visschedijk, Antoon; Denier van der Gon, Hugo A. C.; Amann, Markus

    2016-06-01

    Atmospheric aerosol particle number concentrations impact our climate and health in ways different from those of aerosol mass concentrations. However, the global, current and future anthropogenic particle number emissions and their size distributions are so far poorly known. In this article, we present the implementation of particle number emission factors and the related size distributions in the GAINS (Greenhouse Gas-Air Pollution Interactions and Synergies) model. This implementation allows for global estimates of particle number emissions under different future scenarios, consistent with emissions of other pollutants and greenhouse gases. In addition to determining the general particulate number emissions, we also describe a method to estimate the number size distributions of the emitted black carbon particles. The first results show that the sources dominating the particle number emissions are different to those dominating the mass emissions. The major global number source is road traffic, followed by residential combustion of biofuels and coal (especially in China, India and Africa), coke production (Russia and China), and industrial combustion and processes. The size distributions of emitted particles differ across the world, depending on the main sources: in regions dominated by traffic and industry, the number size distribution of emissions peaks in diameters range from 20 to 50 nm, whereas in regions with intensive biofuel combustion and/or agricultural waste burning, the emissions of particles with diameters around 100 nm are dominant. In the baseline (current legislation) scenario, the particle number emissions in Europe, Northern and Southern Americas, Australia, and China decrease until 2030, whereas especially for India, a strong increase is estimated. The results of this study provide input for modelling of the future changes in aerosol-cloud interactions as well as particle number related adverse health effects, e.g. in response to tightening

  11. Continental anthropogenic primary particle number emissions

    Directory of Open Access Journals (Sweden)

    P. Paasonen

    2016-06-01

    Full Text Available Atmospheric aerosol particle number concentrations impact our climate and health in ways different from those of aerosol mass concentrations. However, the global, current and future anthropogenic particle number emissions and their size distributions are so far poorly known. In this article, we present the implementation of particle number emission factors and the related size distributions in the GAINS (Greenhouse Gas–Air Pollution Interactions and Synergies model. This implementation allows for global estimates of particle number emissions under different future scenarios, consistent with emissions of other pollutants and greenhouse gases. In addition to determining the general particulate number emissions, we also describe a method to estimate the number size distributions of the emitted black carbon particles. The first results show that the sources dominating the particle number emissions are different to those dominating the mass emissions. The major global number source is road traffic, followed by residential combustion of biofuels and coal (especially in China, India and Africa, coke production (Russia and China, and industrial combustion and processes. The size distributions of emitted particles differ across the world, depending on the main sources: in regions dominated by traffic and industry, the number size distribution of emissions peaks in diameters range from 20 to 50 nm, whereas in regions with intensive biofuel combustion and/or agricultural waste burning, the emissions of particles with diameters around 100 nm are dominant. In the baseline (current legislation scenario, the particle number emissions in Europe, Northern and Southern Americas, Australia, and China decrease until 2030, whereas especially for India, a strong increase is estimated. The results of this study provide input for modelling of the future changes in aerosol–cloud interactions as well as particle number related adverse health effects, e.g. in response

  12. Efficient continuous-wave 1112 nm Nd:YAG laser operation under direct diode pumping at 885 nm

    International Nuclear Information System (INIS)

    Gao, J; Dai, X J; Zhang, L; Wu, X D

    2013-01-01

    We report compact diode-end-pumped continuous-wave laser operation at 1112 nm under 885 nm diode-direct pumping for the first time. On the basis of the R 2 →Y 6 transition in a conventional Nd:YAG (yttrium aluminum garnet) single crystal, the maximum output power of 12.5 W is achieved, with an optical to optical efficiency of 46.6% and a slope efficiency of 52.9%. To the best of our knowledge, this represents the highest output at 1112 nm generated by a diode-end-pumped Nd:YAG laser. Furthermore, it is the highest optical to optical efficiency ever reported for 1112 nm Nd:YAG lasers. The short term power stability is ∼0.32% at 12.0 W output. (letter)

  13. Size dependent compressibility of nano-ceria: Minimum near 33 nm

    International Nuclear Information System (INIS)

    Rodenbough, Philip P.; Song, Junhua; Chan, Siu-Wai; Walker, David; Clark, Simon M.; Kalkan, Bora

    2015-01-01

    We report the crystallite-size-dependency of the compressibility of nanoceria under hydrostatic pressure for a wide variety of crystallite diameters and comment on the size-based trends indicating an extremum near 33 nm. Uniform nano-crystals of ceria were synthesized by basic precipitation from cerium (III) nitrate. Size-control was achieved by adjusting mixing time and, for larger particles, a subsequent annealing temperature. The nano-crystals were characterized by transmission electron microscopy and standard ambient x-ray diffraction (XRD). Compressibility, or its reciprocal, bulk modulus, was measured with high-pressure XRD at LBL-ALS, using helium, neon, or argon as the pressure-transmitting medium for all samples. As crystallite size decreased below 100 nm, the bulk modulus first increased, and then decreased, achieving a maximum near a crystallite diameter of 33 nm. We review earlier work and examine several possible explanations for the peaking of bulk modulus at an intermediate crystallite size

  14. Size dependent compressibility of nano-ceria: Minimum near 33 nm

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbough, Philip P. [Department of Applied Physics and Applied Mathematics, Materials Science and Engineering Program, Columbia University, New York, New York 10027 (United States); Chemistry Department, Columbia University, New York, New York 10027 (United States); Song, Junhua; Chan, Siu-Wai, E-mail: sc174@columbia.edu [Department of Applied Physics and Applied Mathematics, Materials Science and Engineering Program, Columbia University, New York, New York 10027 (United States); Walker, David [Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964 (United States); Clark, Simon M. [ARC Center of Excellence for Core to Crust Fluid Systems and Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2019, Australia and The Bragg Institute, Australian Nuclear Science and Technology Organisation, Kirrawee DC, New South Wales 2232 (Australia); Kalkan, Bora [Department of Physics Engineering, Hacettepe University, 06800 Beytepe, Ankara (Turkey)

    2015-04-20

    We report the crystallite-size-dependency of the compressibility of nanoceria under hydrostatic pressure for a wide variety of crystallite diameters and comment on the size-based trends indicating an extremum near 33 nm. Uniform nano-crystals of ceria were synthesized by basic precipitation from cerium (III) nitrate. Size-control was achieved by adjusting mixing time and, for larger particles, a subsequent annealing temperature. The nano-crystals were characterized by transmission electron microscopy and standard ambient x-ray diffraction (XRD). Compressibility, or its reciprocal, bulk modulus, was measured with high-pressure XRD at LBL-ALS, using helium, neon, or argon as the pressure-transmitting medium for all samples. As crystallite size decreased below 100 nm, the bulk modulus first increased, and then decreased, achieving a maximum near a crystallite diameter of 33 nm. We review earlier work and examine several possible explanations for the peaking of bulk modulus at an intermediate crystallite size.

  15. Experimental Studies of Simultaneous 351 nm and 527 nm Laser Beam Interactions in a Long Scalelength Plasma

    International Nuclear Information System (INIS)

    Moody, J D; Divol, L; Glenzer, S H; MacKinnon, A J; Froula, D H; Gregori, G; Kruer, W L; Suter, L J; Williams, E A; Bahr, R; Seka, W

    2003-01-01

    We describe experiments investigating the simultaneous backscattering from 351 nm (3w) and 527 nm (2w) interaction beams in a long scalelength laser-produced plasma for intensities (le) 1 x 10 15 W/cm 2 . Measurements show comparable scattering fractions for both color probe beams. Time resolved spectra of stimulated Raman and Brillouin scattering (SRS and SBS) indicate the effects of laser intensity and smoothing as well as plasma composition and parameters on the scattering levels

  16. In-Situ Characteristics of Particle Emissions from Biomass Combustion

    International Nuclear Information System (INIS)

    Pagels, Joakum; Wierzbicka, Aneta; Bohgard, Mats; Strand, Michael; Lillieblad, Lena; Sanati, Mehri; Swietlicki, Erik

    2005-01-01

    In this work we used a Scanning Mobility Particle Sizer and an Electrical Low-pressure Impactor to: a) Derive information of the particle morphology through air-borne analysis and b) Identify time and size variations of particle phase components from incomplete combustion and ash-components. The results presented here covers measurements in two moving grate boilers (12 MW operating on moist forest residue and 1.5 MW operating on wood pellets). We have previously shown that PM1 estimated from Electrical Low-Pressure Impactor (ELPI)-measurements consisted of a rather constant background with peaks correlating with CO and OGC peaks. In the 1.5 MW boiler EC contributed to 34% of PM1, while in the 12 MW boiler EC was below 0.5%. Figure 2 shows time variations in the 1.5 MW boiler as the current in three stages of the ELPI-impactor. Note that time-variations increase strongly with particle size. The fraction of the gravimetric mass detected as water-soluble ions (IC) decreased from ∼ 70% for dae= 78 and 133 nm to ∼ 25% for 322 and 510 nm particles and increased to around 50% for particles larger than 1 μm. In the 12 MW boiler time variations were as low as for 128 nm particles and IC recovery was high for all studied particle sizes. Based on these data we conclude that PM consisting of ash-components are formed with small time variations mainly in mobility-sizes below 250 nm, while Elemental Carbon is emitted at high concentrations during peaks on the time-scale 10-30 s, mainly in particle sizes larger than 150 nm. However, the detailed mixing status of these two particle types/materials is still not known

  17. Particle kickers

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    These devices are designed to provide a current pulse of 5000 Amps which will in turn generate a fast magnetic pulse that steers the incoming beam into the LHC. Today, the comprehensive upgrade of the LHC injection kicker system is entering its final stages. The upgraded system will ensure the LHC can be refilled without needing to wait for the kicker magnets to cool, thus enhancing the performance of the whole accelerator.   An upgraded kicker magnet in its vacuum tank, with an upgraded beam screen. The LHC is equipped with two kicker systems installed at the injection points (near points 2 and 8, see schematic diagram) where the particle beams coming from the SPS are injected into the accelerator’s orbit. Each system comprises four magnets and four pulse generators in which the field rises to 0.12 Tesla in less than 900 nanoseconds and for a duration of approximately 8 microseconds. Although the injection kickers only pulse 12 times to fill the LHC up with beam, the LHC beam circ...

  18. Ablation from artificial or laser-induced crater surfaces of silver by laser irradiation at 355 nm

    DEFF Research Database (Denmark)

    Toftmann, B.; Schou, Jørgen; Larsen, N.B.

    1999-01-01

    The angular distribution of laser ablated particles from silver irradiated at 355 nm has been studied. The angular distribution from craters prepared by more than 10(4) shots exhibits only minor changes compared with that from a nonirradiated target. The distribution from artificial cylindrical c...... craters of a depth comparable to the laser spot dimensions is about one order of magnitude smaller at large exit angles than that from a flat target.......The angular distribution of laser ablated particles from silver irradiated at 355 nm has been studied. The angular distribution from craters prepared by more than 10(4) shots exhibits only minor changes compared with that from a nonirradiated target. The distribution from artificial cylindrical...

  19. Modeling of particle agglomeration in nanofluids

    International Nuclear Information System (INIS)

    Krishna, K. Hari; Neti, S.; Oztekin, A.; Mohapatra, S.

    2015-01-01

    Agglomeration strongly influences the stability or shelf life of nanofluid. The present computational and experimental study investigates the rate of agglomeration quantitatively. Agglomeration in nanofluids is attributed to the net effect of various inter-particle interaction forces. For the nanofluid considered here, a net inter-particle force depends on the particle size, volume fraction, pH, and electrolyte concentration. A solution of the discretized and coupled population balance equations can yield particle sizes as a function of time. Nanofluid prepared here consists of alumina nanoparticles with the average particle size of 150 nm dispersed in de-ionized water. As the pH of the colloid was moved towards the isoelectric point of alumina nanofluids, the rate of increase of average particle size increased with time due to lower net positive charge on particles. The rate at which the average particle size is increased is predicted and measured for different electrolyte concentration and volume fraction. The higher rate of agglomeration is attributed to the decrease in the electrostatic double layer repulsion forces. The rate of agglomeration decreases due to increase in the size of nano-particle clusters thus approaching zero rate of agglomeration when all the clusters are nearly uniform in size. Predicted rates of agglomeration agree adequate enough with the measured values; validating the mathematical model and numerical approach is employed

  20. Chip development in 65 nm CMOS technology for the high luminosity upgrade of the ATLAS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Germic, Leonard; Hemperek, Tomasz; Kishishita, Testsuichi; Krueger, Hans; Rymaszewski, Piotr; Wermes, Norbert [University of Bonn, Bonn (Germany); Havranek, Miroslav [University of Bonn, Bonn (Germany); Institute of Physics of the Academy of Sciences, Prague (Czech Republic)

    2015-07-01

    The LHC High Luminosity upgrade will result in a significant change of environment in which particle detectors are going to operate, especially for devices very close to the interaction point like pixel detector electronics. Challenges coming from the higher hit rate will have to be solved by designing faster and more complex circuits, while at the same time keeping in mind very high radiation hardness requirements. Therefore matching the specification set by the high luminosity upgrade requires a large R and D effort. Our group is participating in such a joint development * namely the RD53 collaboration * which goal is to design a new pixel chip using an advanced 65 nm CMOS technology. During this presentation motivations and benefits of using this very deep-submicron technology will be shown together with a comparison with older technologies (130 nm, 250 nm). Most of the talk is allocated to presenting some of the circuits designed by our group, along with their performance measurement results.

  1. Absorption spectrum of DNA for wavelengths greater than 300 nm

    International Nuclear Information System (INIS)

    Sutherland, J.C.; Griffin, K.P.

    1981-01-01

    Although DNA absorption at wavelengths greater than 300 nm is much weaker than that at shorter wavelengths, this absorption seems to be responsible for much of the biological damage caused by solar radiation of wavelengths less than 320 nm. Accurate measurement of the absorption spectrum of DNA above 300 nm is complicated by turbidity characteristic of concentrated solutions of DNA. We have measured the absorption spectra of DNA from calf thymus, Clostridium perfringens, Escherichia coli, Micrococcus luteus, salmon testis, and human placenta using procedures which separate optical density due to true absorption from that due to turbidity. Above 300 nm, the relative absorption of DNA increases as a function of guanine-cytosine content, presumably because the absorption of guanine is much greater than the absorption of adenine at these wavelengths. This result suggests that the photophysical processes which follow absorption of a long-wavelength photon may, on the average, differ from those induced by shorter-wavelength photons. It may also explain the lower quantum yield for the killing of cells by wavelengths above 300 nm compared to that by shorter wavelengths

  2. 100-nm gate lithography for double-gate transistors

    Science.gov (United States)

    Krasnoperova, Azalia A.; Zhang, Ying; Babich, Inna V.; Treichler, John; Yoon, Jung H.; Guarini, Kathryn; Solomon, Paul M.

    2001-09-01

    The double gate field effect transistor (FET) is an exploratory device that promises certain performance advantages compared to traditional CMOS FETs. It can be scaled down further than the traditional devices because of the greater electrostatic control by the gates on the channel (about twice as short a channel length for the same gate oxide thickness), has steeper sub-threshold slope and about double the current for the same width. This paper presents lithographic results for double gate FET's developed at IBM's T. J. Watson Research Center. The device is built on bonded wafers with top and bottom gates self-aligned to each other. The channel is sandwiched between the top and bottom polysilicon gates and the gate length is defined using DUV lithography. An alternating phase shift mask was used to pattern gates with critical dimensions of 75 nm, 100 nm and 125 nm in photoresist. 50 nm gates in photoresist have also been patterned by 20% over-exposure of nominal 100 nm lines. No trim mask was needed because of a specific way the device was laid out. UV110 photoresist from Shipley on AR-3 antireflective layer were used. Process windows, developed and etched patterns are presented.

  3. Magnetic Nature of Light Transmission through a 5-nm Gap.

    Science.gov (United States)

    Yang, Hyosim; Kim, Dai-Sik; Kim, Richard H Joon-Yeon; Ahn, Jae Sung; Kang, Taehee; Jeong, Jeeyoon; Lee, Dukhyung

    2018-02-09

    Slot antennas have been exploited as important building blocks of optical magnetism because their radiations are invoked by the magnetic fields along the axes, as vectorial Babinet principle predicts. However, optical magnetism of a few-nanometer-width slit, for which fascinating applications are found due to the colossal field enhancement but Babinet principle fails due to the nonnegligible thickness, has not been investigated. In this paper, we demonstrated that the magnetic field plays a dominant role in light transmission through a 5-nm slit on a 150-nm-thick gold film. The 5-nm slit was fabricated by atomic layer lithography, and the transmission was investigated for various incident angles by experiment and simulation at 785-nm wavelength. We found that, due to the deep subwavelength gap width, the transmission has the same incident angle dependence as the tangential magnetic field on the metal surface and this magnetic nature of a nanogap holds up to ~100-nm width. Our analysis establishes conditions for nanogap optical magnetism and suggests new possibilities in realizing magnetic-field-driven optical nonlinearities.

  4. First tests of CHERWELL, a Monolithic Active Pixel Sensor: A CMOS Image Sensor (CIS) using 180 nm technology

    Energy Technology Data Exchange (ETDEWEB)

    Mylroie-Smith, James, E-mail: j.mylroie-smith@qmul.ac.uk [Queen Mary, University of London (United Kingdom); Kolya, Scott; Velthuis, Jaap [University of Bristol (United Kingdom); Bevan, Adrian; Inguglia, Gianluca [Queen Mary, University of London (United Kingdom); Headspith, Jon; Lazarus, Ian; Lemon, Roy [Daresbury Laboratory, STFC (United Kingdom); Crooks, Jamie; Turchetta, Renato; Wilson, Fergus [Rutherford Appleton Laboratory, STFC (United Kingdom)

    2013-12-11

    The Cherwell is a 4T CMOS sensor in 180 nm technology developed for the detection of charged particles. Here, the different test structures on the sensor will be described and first results from tests on the reference pixel variant are shown. The sensors were shown to have a noise of 12 e{sup −} and a signal to noise up to 150 in {sup 55}Fe.

  5. Diurnal and seasonal variations of concentration and size distribution of nano aerosols (10-1100 nm) enclosing radon decay products in the Postojna Cave, Slovenia

    International Nuclear Information System (INIS)

    Bezek, M.; Gregoric, A.; Kavasi, N.; Vaupotic, J.

    2012-01-01

    At the lowest point along the tourist route in the Postojna Cave, the activity concentration of radon ( 222 Rn) short-lived decay products and number concentration and size distribution of background aerosol particles in the size range of 10-1100 nm were measured. In the warm yearly season, aerosol concentration was low (52 cm -3 ) with 21 % particles smaller than 50 nm, while in the cold season, it was higher (1238 cm -3 ) with 8 % of -3 , and fractions of unattached radon decay products were 0.62 and 0.13, respectively. (authors)

  6. Prototyping the HPDP Chip on STM 65 NM Process

    Science.gov (United States)

    Papadas, C.; Dramitinos, G.; Syed, M.; Helfers, T.; Dedes, G.; Schoellkopf, J.-P.; Dugoujon, L.

    2011-08-01

    Currently Astrium GmbH is involved in the of the High Performance Data Processor (HPDP) development programme for telecommunication applications under a DLR contract. The HPDP project targets the implementation of the commercially available reconfigurable array processor IP (XPP from the company PACT XPP Technologies) in a radiation hardened technology.In the current complementary development phase funded under the Greek Industry Incentive scheme, it is planned to prototype the HPDP chip in commercial STM 65 nm technology. In addition it is also planned to utilise the preliminary radiation hardened components of this library wherever possible.This abstract gives an overview of the HPDP chip architecture, the basic details of the STM 65 nm process and the design flow foreseen for the prototyping. The paper will discuss the development and integration issues involved in using the STM 65 nm process (also including the available preliminary radiation hardened components) for designs targeted to be used in space applications.

  7. Large-scale lithography for sub-500nm features

    International Nuclear Information System (INIS)

    Pelzer, R L; Steininger, T; Belier, Benoit; Julie, Gwenaelle

    2006-01-01

    The interest in micro- and nanotechnologies has grown rapidly in the last years. The applications are versatile and different techniques found its way into several research domains as optics, electronics, magnetism, fluidics, etc. In all of these fields integration of more and more functions on steadily decreasing device dimensions lead to an increase in structural density and feature size. Expensive and slow processes utilizing projection steppers or e-beam direct writer equipment are used to fabricate nm features today. A high throughput and cost effective method adapted on a standard mask aligner will be demonstrated, making features of below 300nm available on wafer-level. We will demonstrate results of 4 different resists exposed on a DUV proximity aligner and plasma etched for optical and biological applications in the sub-300nm range

  8. Large-scale lithography for sub-500nm features

    Energy Technology Data Exchange (ETDEWEB)

    Pelzer, R L [Technology group, EV Group, DI Erich Thallner Str. 1, A-4780 Schaerding (Austria); Steininger, T [Technology group, EV Group, DI Erich Thallner Str. 1, A-4780 Schaerding (Austria); Belier, Benoit [CNRS, Institut d' Electronique Fondamentale, Universite Paris-Sud Bat 220, F- 91405 Orsay Cedex (France); Julie, Gwenaelle [CNRS, Institut d' Electronique Fondamentale, Universite Paris-Sud Bat 220, F- 91405 Orsay Cedex (France)

    2006-04-01

    The interest in micro- and nanotechnologies has grown rapidly in the last years. The applications are versatile and different techniques found its way into several research domains as optics, electronics, magnetism, fluidics, etc. In all of these fields integration of more and more functions on steadily decreasing device dimensions lead to an increase in structural density and feature size. Expensive and slow processes utilizing projection steppers or e-beam direct writer equipment are used to fabricate nm features today. A high throughput and cost effective method adapted on a standard mask aligner will be demonstrated, making features of below 300nm available on wafer-level. We will demonstrate results of 4 different resists exposed on a DUV proximity aligner and plasma etched for optical and biological applications in the sub-300nm range.

  9. CALIPSO lidar calibration at 532 nm: version 4 nighttime algorithm

    Directory of Open Access Journals (Sweden)

    J. Kar

    2018-03-01

    Full Text Available Data products from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP on board Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO were recently updated following the implementation of new (version 4 calibration algorithms for all of the Level 1 attenuated backscatter measurements. In this work we present the motivation for and the implementation of the version 4 nighttime 532 nm parallel channel calibration. The nighttime 532 nm calibration is the most fundamental calibration of CALIOP data, since all of CALIOP's other radiometric calibration procedures – i.e., the 532 nm daytime calibration and the 1064 nm calibrations during both nighttime and daytime – depend either directly or indirectly on the 532 nm nighttime calibration. The accuracy of the 532 nm nighttime calibration has been significantly improved by raising the molecular normalization altitude from 30–34 km to the upper possible signal acquisition range of 36–39 km to substantially reduce stratospheric aerosol contamination. Due to the greatly reduced molecular number density and consequently reduced signal-to-noise ratio (SNR at these higher altitudes, the signal is now averaged over a larger number of samples using data from multiple adjacent granules. Additionally, an enhanced strategy for filtering the radiation-induced noise from high-energy particles was adopted. Further, the meteorological model used in the earlier versions has been replaced by the improved Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2, model. An aerosol scattering ratio of 1.01 ± 0.01 is now explicitly used for the calibration altitude. These modifications lead to globally revised calibration coefficients which are, on average, 2–3 % lower than in previous data releases. Further, the new calibration procedure is shown to eliminate biases at high altitudes that were present in earlier versions and

  10. Particle Emissions from Biomass Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Szpila, Aneta; Bohgard, Mats [Lund Inst. of Technology (Sweden). Div. of Ergonomics and Aerosol Technology; Strand, Michael; Lillieblad, Lena; Sanati, Mehri [Vaexjoe Univ. (Sweden). Div. of Bioenergy Technology; Pagels, Joakim; Rissler, Jenny; Swietlicki, Erik; Gharibi, Arash [Lund Univ. (Sweden). Div. of Nuclear Physics

    2003-05-01

    particle number concentration increased slightly with increasing load, at the same time the fine mode particles became smaller. This was probably caused by different degree of particle coagulation as the residence time in the boiler was changed. The mean diameter during combustion of forest residue was around 100 nm compared to 70-80 nm for dry wood and pellets, while the total number was close to constant. This explains the differences in mass concentration found in the impactor measurements. The concentrations of CO and THC was highest for the dry wood fuel, the PAH concentration was highest for pellets combustion in boiler 4, however this boiler was poorly tuned at the time of measurement. The PAH concentration was 5 times higher during combustion of dry wood compared to forest residue. The concentration of CO, THC and PAH varied to a great extend. The high concentrations were measured in boilers running at a low load. The concentration of particle organic carbon was less than 15% of PMI for all fuels. However we used heated primary dilution, which inhibits the condensation of organic components into, the particle phase. A significant fraction of the emitted organic carbon may condense to the particle phase during dilution after the stack or after being oxidized in the atmosphere. We also measured elemental carbon in the particle phase. The contribution to PM1 was as high as 25-30% during pellets combustion at low load and 8% at low load during combustion of dry wood. In all other cases the EC-concentration was less than 3% of PMI. PIXE and lon-chromatography confirmed that alkali-salts were the dominant chemical species. PIXE analysis revealed that emitted amounts of heavy metals such as Zn, Cd and Pb are strongly dependent on the type of the fuel used. Forest residues gave high emissions of Zn, Cd and Pb, while pellets gave very high emissions of Cd and Zn. The fuel with the lowest emissions of heavy metals was dry wood. This again could be related to ash content in

  11. Extreme Ultraviolet Process Optimization for Contact Layer of 14 nm Node Logic and 16 nm Half Pitch Memory Devices

    Science.gov (United States)

    Tseng, Shih-En; Chen, Alek

    2012-06-01

    Extreme ultraviolet (EUV) lithography is considered the most promising single exposure technology at the 27 nm half-pitch node and beyond. The imaging performance of ASML TWINSCAN NXE:3100 has been demonstrated to be able to resolve 26 nm Flash gate layer and 16 nm static random access memory (SRAM) metal layer with a 0.25 numerical aperture (NA) and conventional illumination. Targeting for high volume manufacturing, ASML TWINSCAN NXE:3300B, featuring a 0.33 NA lens with off-axis illumination, will generate a higher contrast aerial image due to improved diffraction order collection efficiency and is expected to reduce target dose via mask biasing. This work performed a simulation to determine how EUV high NA imaging benefits the mask rule check trade-offs required to achieve viable lithography solutions in two device application scenarios: a 14 nm node 6T-SRAM contact layer and a 16 nm half-pitch NAND Flash staggered contact layer. In each application, the three-dimensional mask effects versus Kirchhoff mask were also investigated.

  12. REAL TIME MEASUREMENT OF ULTRAFINE AND NANO PARTICLES AND SIGNIFICANCE OF OPERATING GEARS

    Directory of Open Access Journals (Sweden)

    H. A. NAKHAWA

    2017-03-01

    Full Text Available This research paper focuses on characterization of ultrafine and nanoparticle emissions from diesel vehicle to investigate their physical characterization in terms of number and size as they are more vulnerable and responsible for toxicity, mutagenicity and carcinogenicity. An investigation has been carried out to identify the significance of different operating gears, clutch, declutch and gear change operations for their contributions to particle number(PN on urban and extra urban part of the driving cycle. A bi-modal particle size distribution pattern was observed for both urban and extra urban parts where almost all the particles are below 200 nm and particle number peaks appear at 7 to 8 nm and at 70 nm. Nano particles contribute approximately, 70% of total particle number over urban part. Experimental investigation shows that the most significant gear for their contribution to particle number are 3rd and 5th gears on urban and extra urban part of the driving cycle respectively.

  13. Fermilab | Science | Particle Physics

    Science.gov (United States)

    Photos and videos Latest news For the media Particle Physics Neutrinos Fermilab and the LHC Dark matter initiatives Research and development Key discoveries Benefits of particle physics Particle Accelerators society Particle Physics 101 Science of matter, energy, space and time How particle physics discovery

  14. Gold/silver core-shell 20 nm nanoparticles extracted from citrate solution examined by XPS

    Energy Technology Data Exchange (ETDEWEB)

    Engelhard, Mark H.; Smith, Jordan N.; Baer, Donald R.

    2016-06-01

    Silver nanoparticles of many types are widely used in consumer and medical products. The surface chemistry of particles and the coatings that form during synthesis or use in many types of media can significantly impact the behaviors of particles including dissolution, transformation and biological or environmental impact. Consequently it is useful to be able to extract information about the thickness of surface coatings and other attributes of nanoparticles produced in a variety of ways. It has been demonstrated that X-ray Photoelectron Spectroscopy (XPS) can be reliably used to determine the thickness of organic and other nanoparticles coatings and shells. However, care is required to produce reliable and consistent information. Here we report the XPS spectra from gold/silver core-shell nanoparticles of nominal size 20 nm removed from a citrate saturated solution after one and two washing cycles. The Simulation of Electron Spectra for Surface Analysis (SESSA) program had been used to model peak amplitudes to obtain information on citrate coatings that remain after washing and demonstrate the presence of the gold core. This data is provided so that others can compare use of SESSA or other modeling approaches to quantify the nature of coatings to those already published and to explore the impacts particle non-uniformities on XPS signals from core-shell nanoparticles.

  15. Cutting the Gordian Knot of electrodeposition via controlled cathodic corrosion enabling the production of supported metal nanoparticles below 5 nm

    OpenAIRE

    Vanrenterghem, B.; Bele, M.; Zepeda, F.R.; Sala, M.; Hodnik, N.; Breugelmans, Tom

    2018-01-01

    Abstract: In the past decades, there has been an ongoing search for tailor-made active metal nanoparticles for the use as electrocatalysts. An upcoming versatile and green method for the synthesis of nanoparticles is electrodeposition. However, the state-of-the-art electrodeposited metal particle sizes are in the range of 50200 nm. Production of high surface area metallic electrocatalysts with small particle sizes is a serious limitation of electrodeposition, i.e., the Gordian Knot. In this a...

  16. On-chip measurements of Brownian relaxation of magnetic beads with diameters from 10 nm to 250 nm

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Rizzi, Giovanni; Hansen, Mikkel Fougt

    2013-01-01

    We demonstrate the use of planar Hall effect magnetoresistive sensors for AC susceptibility measurements of magnetic beads with frequencies ranging from DC to 1 MHz. This wide frequency range allows for measuring Brownian relaxation of magnetic beads with diameters ranging from 10 nm to 250 nm....... Brownian relaxation is measured for six different magnetic bead types and their hydrodynamic diameters are determined. The hydrodynamic diameters are found to be within 40% of the nominal bead diameters. We discuss the applicability of the different bead types for volume-based biosensing with respect...... to sedimentation, magnetic trapping, and signal per bead. Among the investigated beads, we conclude that the beads with a nominal diameter of 80 nm are best suited for future on-chip volume-based biosensing experiments using planar Hall effect sensors....

  17. [Ultrafine particle number concentration and size distribution of vehicle exhaust ultrafine particles].

    Science.gov (United States)

    Lu, Ye-qiang; Chen, Qiu-fang; Sun, Zai; Cai, Zhi-liang; Yang, Wen-jun

    2014-09-01

    Ultrafine particle (UFP) number concentrations obtained from three different vehicles were measured using fast mobility particle sizer (FMPS) and automobile exhaust gas analyzer. UFP number concentration and size distribution were studied at different idle driving speeds. The results showed that at a low idle speed of 800 rmin-1 , the emission particle number concentration was the lowest and showed a increasing trend with the increase of idle speed. The majority of exhaust particles were in Nuclear mode and Aitken mode. The peak sizes were dominated by 10 nm and 50 nm. Particle number concentration showed a significantly sharp increase during the vehicle acceleration process, and was then kept stable when the speed was stable. In the range of 0. 4 m axial distance from the end of the exhaust pipe, the particle number concentration decayed rapidly after dilution, but it was not obvious in the range of 0. 4-1 m. The number concentration was larger than the background concentration. Concentration of exhaust emissions such as CO, HC and NO showed a reducing trend with the increase of idle speed,which was in contrast to the emission trend of particle number concentration.

  18. Number size distribution of fine and ultrafine fume particles from various welding processes.

    Science.gov (United States)

    Brand, Peter; Lenz, Klaus; Reisgen, Uwe; Kraus, Thomas

    2013-04-01

    Studies in the field of environmental epidemiology indicate that for the adverse effect of inhaled particles not only particle mass is crucial but also particle size is. Ultrafine particles with diameters below 100 nm are of special interest since these particles have high surface area to mass ratio and have properties which differ from those of larger particles. In this paper, particle size distributions of various welding and joining techniques were measured close to the welding process using a fast mobility particle sizer (FMPS). It turned out that welding processes with high mass emission rates (manual metal arc welding, metal active gas welding, metal inert gas welding, metal inert gas soldering, and laser welding) show mainly agglomerated particles with diameters above 100 nm and only few particles in the size range below 50 nm (10 to 15%). Welding processes with low mass emission rates (tungsten inert gas welding and resistance spot welding) emit predominantly ultrafine particles with diameters well below 100 nm. This finding can be explained by considerably faster agglomeration processes in welding processes with high mass emission rates. Although mass emission is low for tungsten inert gas welding and resistance spot welding, due to the low particle size of the fume, these processes cannot be labeled as toxicologically irrelevant and should be further investigated.

  19. Modeling of Particle Agglomeration in Nanofluids

    Science.gov (United States)

    Kanagala, Hari Krishna

    Nanofluids are colloidal dispersions of nano sized particles (life of these nanofluids. Current research addresses the agglomeration effect and how it can affect the shelf life of a nanofluid. The reasons for agglomeration in nanofluids are attributable to the interparticle interactions which are quantified by the various theories. By altering the governing properties like volume fraction, pH and electrolyte concentration different nanofluids with instant agglomeration, slow agglomeration and no agglomeration can be produced. A numerical model is created based on the discretized population balance equations which analyses the particle size distribution at different times. Agglomeration effects have been analyzed for alumina nanoparticles with average particle size of 150nm dispersed in de-ionized water. As the pH was moved towards the isoelectric point of alumina nanofluids, the particle size distribution became broader and moved to bigger sizes rapidly with time. Particle size distributions became broader and moved to bigger sizes more quickly with time with increase in the electrolyte concentration. The two effects together can be used to create different temporal trends in the particle size distributions. Faster agglomeration is attributed to the decrease in the electrostatic double layer repulsion forces which is due to decrease in the induced charge and the double layer thickness around the particle. Bigger particle clusters show lesser agglomeration due to reaching the equilibrium size. The procedures and processes described in this work can be used to generate more stable nanofluids.

  20. FDML swept source at 1060 nm using a tapered amplifier

    DEFF Research Database (Denmark)

    Marschall, Sebastian; Klein, Thomas; Wieser, Wolfgang

    2010-01-01

    We present a novel frequency-swept light source working at 1060nm that utilizes a tapered amplifier as gain medium. These devices feature significantly higher saturation power than conventional semiconductor optical amplifiers and can thus improve the limited output power of swept sources in this...... an axial resolution of 15 µm in air (~11µm in tissue) for OCT applications can be achieved....

  1. A novel double patterning approach for 30nm dense holes

    Science.gov (United States)

    Hsu, Dennis Shu-Hao; Wang, Walter; Hsieh, Wei-Hsien; Huang, Chun-Yen; Wu, Wen-Bin; Shih, Chiang-Lin; Shih, Steven

    2011-04-01

    Double Patterning Technology (DPT) was commonly accepted as the major workhorse beyond water immersion lithography for sub-38nm half-pitch line patterning before the EUV production. For dense hole patterning, classical DPT employs self-aligned spacer deposition and uses the intersection of horizontal and vertical lines to define the desired hole patterns. However, the increase in manufacturing cost and process complexity is tremendous. Several innovative approaches have been proposed and experimented to address the manufacturing and technical challenges. A novel process of double patterned pillars combined image reverse will be proposed for the realization of low cost dense holes in 30nm node DRAM. The nature of pillar formation lithography provides much better optical contrast compared to the counterpart hole patterning with similar CD requirements. By the utilization of a reliable freezing process, double patterned pillars can be readily implemented. A novel image reverse process at the last stage defines the hole patterns with high fidelity. In this paper, several freezing processes for the construction of the double patterned pillars were tested and compared, and 30nm double patterning pillars were demonstrated successfully. A variety of different image reverse processes will be investigated and discussed for their pros and cons. An economic approach with the optimized lithography performance will be proposed for the application of 30nm DRAM node.

  2. 650 nm Laser stimulated dating from Side Antique Theatre, Turkey

    International Nuclear Information System (INIS)

    Doğan, M.; Meriç, N.

    2014-01-01

    Samples were taken from the archeological excavation site, which was at the backs of the Side Antique Theatre. Samples were taken from under the base rock in this area. Polymineral fine grains were examined to determine the ages of the sediments. Samples gathered from the Side Antique Theatre were investigated through using the SAR method. Firstly, one part of the samples were evaluated by using conventional IRSL reading head model of (ELSEC-9010) which is infrared (880±80 nm) stimulation source with Schott BG39 filter. The IRSL age dating with feldspar minerals, gives a number of overestimated or underestimated age values as a result. A new reading head was proposed with the following configuration attachments for overestimation of equivalent dose rates. Measurements were done with this newly designed red laser stimulating reading head which works with Elsec 9010 OSL age dating system. SAR measurements were performed by (650±10 nm) red laser light source with two Schott BG3 filters. With usage of the new designed reading head; closer results were obtained in comparision with the Antique Theatre′s expected age range. Fading rates were taken into consideration and these corrections were also handled for true age results. - Highlights: • Polymineral fine grain feldspar minerals were used for dating. • Two different reading heads were used to determine equivalent doses. • IR stimulated (880 nm) and laser stimulated (650 nm) dating results were compared

  3. Isolation and genomic characterization of Escherichia coli O157:NM ...

    African Journals Online (AJOL)

    Human diseases caused by Escherichia coli O157:NM and E. coli O157:H7 strains have been reported throughout the world. In developed countries, serotype O157:H7 represents the major cause of human diseases; however, there have been increasing reports of non-O157 Shiga toxin (Stx)-producing E. coli strains ...

  4. 78 FR 72141 - New Mexico Disaster Number NM-00037

    Science.gov (United States)

    2013-12-02

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13787 and 13788] New Mexico Disaster Number NM... Mexico (FEMA-4148-DR), dated 09/30/2013. Incident: Severe Storms and Flooding Incident Period: 07/23/2013... INFORMATION: The notice of the President's major disaster declaration for Private Non-Profit organizations in...

  5. 76 FR 2431 - New Mexico Disaster #NM-00016

    Science.gov (United States)

    2011-01-13

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12320 and 12321] New Mexico Disaster NM-00016... Presidential declaration of a major disaster for Public Assistance Only for the State of New Mexico (FEMA-1936... INFORMATION: The notice of the President's major disaster declaration for Private Non-Profit organizations in...

  6. 78 FR 73581 - New Mexico Disaster Number NM-00035

    Science.gov (United States)

    2013-12-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13809 and 13810] New Mexico Disaster Number NM... Mexico (FEMA-4152-DR), dated 10/29/2013. Incident: Severe Storms, Flooding, and Mudslides. Incident... 20416. SUPPLEMENTARY INFORMATION: The notice of the President's major disaster declaration for Private...

  7. 77 FR 63409 - New Mexico Disaster Number NM-00029

    Science.gov (United States)

    2012-10-16

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13252 and 13253] New Mexico Disaster Number NM... Mexico (FEMA-4079-DR), dated 08/24/2012. Incident: Flooding. Incident Period: 06/22/2012 through 07/12... the President's major disaster declaration for Private Non-Profit organizations in the State of NEW...

  8. 78 FR 66982 - New Mexico Disaster #NM-00035

    Science.gov (United States)

    2013-11-07

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13809 and 13810] New Mexico Disaster NM-00035... declaration of a major disaster for Public Assistance Only for the State of New Mexico (FEMA- 4152-DR), dated... INFORMATION: Notice is hereby given that as a result of the President's major disaster declaration on 10/29...

  9. 76 FR 81553 - New Mexico Disaster Number NM-00024

    Science.gov (United States)

    2011-12-28

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12940 and 12941] New Mexico Disaster Number NM... Mexico (FEMA-4047-DR), dated 11/23/2011. Incident: Flooding. Incident Period: 08/19/2011 through 08/24... INFORMATION: The notice of the President's major disaster declaration for Private Non-Profit organizations in...

  10. EST Table: NM_001043366 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001043366 Sap-r 10/09/29 98 %/961 aa ref|NP_001036831.1| saposin-related [Bombyx... gnl|Amel|GB16561-PA 10/09/10 42 %/808 aa gi|91077504|ref|XP_966852.1| PREDICTED: similar to saposin isoform 1 [Tribolium castaneum] FS791050 ...

  11. 308-nm excimer laser for the treatment of alopecia areata.

    Science.gov (United States)

    Al-Mutairi, Nawaf

    2007-12-01

    Alopecia areata is loss of hair from localized or diffuse areas of hair-bearing area of the skin. Recently there are reports of efficacy of the 308-nm excimer radiation for this condition. To study the effect of the 308-nm excimer laser in the treatment of alopecia areata. Eighteen patients with 42 recalcitrant patches (including 1 adult with alopecia totalis) were enrolled in this study. The lesions were treated with the 308-nm excimer laser twice a week for a period of 12 weeks; one lesion on each patient was left as a control for comparison. There were 7 males and 11 females in this study. Regrowth of hair was observed in 17 (41.5%) patches. Thirteen of the 18 lesions in scalp showed a complete regrowth of hair. The extremity regions failed to show a response. Atopic diatheses had an unfavorable effect on the outcome in our patients. The 308-nm excimer laser is an effective therapeutic option for patchy alopecia areata of the scalp and for some cases with patchy alopecia areata of the beard area. It does not work for patchy alopecia areata of the extremities.

  12. Spectral narrowing of a 980 nm tapered diode laser bar

    Science.gov (United States)

    Vijayakumar, Deepak; Jensen, Ole Bjarlin; Lucas Leclin, Ga"lle; Petersen, Paul Michael; Thestrup, Birgitte

    2011-03-01

    High power diode laser bars are interesting in many applications such as solid state laser pumping, material processing, laser trapping, laser cooling and second harmonic generation. Often, the free running laser bars emit a broad spectrum of the order of several nanometres which limit their scope in wavelength specific applications and hence, it is vital to stabilize the emission spectrum of these devices. In our experiment, we describe the wavelength narrowing of a 12 element 980 nm tapered diode laser bar using a simple Littman configuration. The tapered laser bar which suffered from a big smile has been "smile corrected" using individual phase masks for each emitter. The external cavity consists of the laser bar, both fast and slow axis micro collimators, smile correcting phase mask, 6.5x beam expanding lens combination, a 1200 lines/mm reflecting grating with 85% efficiency in the first order, a slow axis focusing cylindrical lens of 40 mm focal length and an output coupler which is 10% reflective. In the free running mode, the laser emission spectrum was 5.5 nm wide at an operating current of 30A. The output power was measured to be in excess of 12W. Under the external cavity operation, the wavelength spread of the laser could be limited to 0.04 nm with an output power in excess of 8 W at an operating current of 30A. The spectrum was found to be tuneable in a range of 16 nm.

  13. Conjugated 12 nm long oligomers as molecular wires in nanoelectronics

    DEFF Research Database (Denmark)

    Søndergaard, Roar; Strobel, Sebastian; Bundgaard, Eva

    2009-01-01

    We demonstrate a generic synthetic approach to oligophenylenevinylene (OPV) derivative molecules with a molecular length of up to 12 nm and a relatively free choice of end group that can attach to different electrodes such as metallic gold or potentially transition metal oxide semiconductors. OPV...

  14. Magneto-optical trap for metastable helium at 389 nm

    NARCIS (Netherlands)

    Koelemeij, J.C.J.; Stas, R.J.W.; Hogervorst, W.; Vassen, W.

    2003-01-01

    We have constructed a magneto-optical trap (MOT) for metastable triplet helium atoms utilizing the 2 S-3(1)-->3 P-3(2) line at 389 nm as the trapping and cooling transition. The far-red-detuned MOT (detuning Delta=-41 MHz) typically contains few times 10(7) atoms at a relatively high (similar

  15. Clearance of iron oxide particles in rat liver: effect of hydrated particle size and coating material on liver metabolism.

    Science.gov (United States)

    Briley-Saebo, Karen C; Johansson, Lars O; Hustvedt, Svein Olaf; Haldorsen, Anita G; Bjørnerud, Atle; Fayad, Zahi A; Ahlstrom, Haakan K

    2006-07-01

    We sought to evaluate the effect of the particle size and coating material of various iron oxide preparations on the rate of rat liver clearance. The following iron oxide formulations were used in this study: dextran-coated ferumoxide (size = 97 nm) and ferumoxtran-10 (size = 21 nm), carboxydextran-coated SHU555A (size = 69 nm) and fractionated SHU555A (size = 12 nm), and oxidized-starch coated materials either unformulated NC100150 (size = 15 nm) or formulated NC100150 injection (size = 12 nm). All formulations were administered to 165 rats at 2 dose levels. Quantitative liver R2* values were obtained during a 63-day time period. The concentration of iron oxide particles in the liver was determined by relaxometry, and these values were used to calculate the particle half-lives in the liver. After the administration of a high dose of iron oxide, the half-life of iron oxide particles in rat liver was 8 days for dextran-coated materials, 10 days for carboxydextran materials, 14 days for unformulated oxidized-starch, and 29 days for formulated oxidized-starch. The results of the study indicate that materials with similar coating but different sizes exhibited similar rates of liver clearance. It was, therefore, concluded that the coating material significantly influences the rate of iron oxide clearance in rat liver.

  16. Porous metal oxide particles and their methods of synthesis

    Science.gov (United States)

    Chen, Fanglin; Liu, Qiang

    2013-03-12

    Methods are generally disclosed for synthesis of porous particles from a solution formed from a leaving agent, a surfactant, and a soluble metal salt in a solvent. The surfactant congregates to form a nanoparticle core such that the metal salt forms about the nanoparticle core to form a plurality of nanoparticles. The solution is heated such that the leaving agent forms gas bubbles in the solution, and the plurality of nanoparticles congregate about the gas bubbles to form a porous particle. The porous particles are also generally disclosed and can include a particle shell formed about a core to define an average diameter from about 0.5 .mu.m to about 50 .mu.m. The particle shell can be formed from a plurality of nanoparticles having an average diameter of from about 1 nm to about 50 nm and defined by a metal salt formed about a surfactant core.

  17. ILT optimization of EUV masks for sub-7nm lithography

    Science.gov (United States)

    Hooker, Kevin; Kuechler, Bernd; Kazarian, Aram; Xiao, Guangming; Lucas, Kevin

    2017-06-01

    The 5nm and 7nm technology nodes will continue recent scaling trends and will deliver significantly smaller minimum features, standard cell areas and SRAM cell areas vs. the 10nm node. There are tremendous economic pressures to shrink each subsequent technology, though in a cost-effective and performance enhancing manner. IC manufacturers are eagerly awaiting EUV so that they can more aggressively shrink their technology than they could by using complicated MPT. The current 0.33NA EUV tools and processes also have their patterning limitations. EUV scanner lenses, scanner sources, masks and resists are all relatively immature compared to the current lithography manufacturing baseline of 193i. For example, lens aberrations are currently several times larger (as a function of wavelength) in EUV scanners than for 193i scanners. Robustly patterning 16nm L/S fully random logic metal patterns and 40nm pitch random logic rectangular contacts with 0.33NA EUV are tough challenges that will benefit from advanced OPC/RET. For example, if an IC manufacturer can push single exposure device layer resolution 10% tighter using improved ILT to avoid using DPT, there will be a significant cost and process complexity benefit to doing so. ILT is well known to have considerable benefits in finding flexible 193i mask pattern solutions to improve process window, improve 2D CD control, improve resolution in low K1 lithography regime and help to delay the introduction of DPT. However, ILT has not previously been applied to EUV lithography. In this paper, we report on new developments which extend ILT method to EUV lithography and we characterize the benefits seen vs. traditional EUV OPC/RET methods.

  18. Treatment of oral lichen planus using 308-nm excimer laser.

    Science.gov (United States)

    Liu, Wei-Bing; Sun, Li-Wei; Yang, Hua; Wang, Yan-Fei

    2017-09-01

    Oral lichen planus (OLP) is a chronic inflammatory disease, has prolonged courses, repeated attacks and resistance to treatment. The traditional narrow spectrum UVB treatment has an established efficacy on skin lichen planus, and high safety. However, most of ultraviolet phototherapy devices have a huge volume, thereby cannot be used in the treatment of OLP. Lymphocytic infiltration is evident in the lesions of lichen planus, and the direct irradiation of 308-nm excimer laser can induce apoptosis of the T lymphocytes in skin lesions, thereby has a unique therapeutic effect on the diseases involving T lymphocytes. This study aims to investigate the efficacy of 308-nm excimer laser in the treatment of OLP. A total of six OLP patients were enrolled into this study, and further pathological diagnosis was conducted, then 308-nm excimer laser was used in the treatment. The efficacy of 308-nm excimer laser in the treatment of OLP was satisfactory. The clinical symptoms of five patients were significantly improved. In two patients, the erosion surface based on congestion and the surrounding white spots completely disappeared, and clinical recovery was achieved. Three patients achieved partial remission, that is, the erosion surface healed, congestion and white spot area shrunk by more than 1/2 of the primary skin lesions. In the remaining one patient, the erosion surface had not completely healed after treatment, and congestion and white spot area shrunk by less than 1/2 of the primary skin lesions. Only one patients had developed mild pain during the treatment, and this symptom alleviated by itself. The 308-nm excimer laser therapy can serve as a safe and effective treatment for OLP. © 2017 Wiley Periodicals, Inc.

  19. Particle theory and cosmology

    International Nuclear Information System (INIS)

    Gaisser, T.K.; Shafi, Q.; Barr, S.M.; Seckel, D.; Rusjan, E.; Fletcher, R.S.

    1991-01-01

    This report discusses research of professor at Bartol research institute in the following general areas: particle phenomenology and non-accelerator physics; particle physics and cosmology; theories with higher symmetry; and particle astrophysics and cosmology

  20. Field measurements of hygroscopic properties and state of mixing of nucleation mode particles

    Directory of Open Access Journals (Sweden)

    M. Väkevä

    2002-01-01

    Full Text Available An Ultrafine Tandem Differential Mobility Analyser (UF-TDMA has been used in several field campaigns over the last few years. The investigations were focused on the origin and properties of nucleation event aerosols, which are observed frequently in various environments. This paper gives a summary of the results of 10 nm and 20 nm particle hygroscopic properties from different measurement sites: an urban site, an urban background site and a forest site in Finland and a coastal site in western Ireland. The data can be classified in four hygroscopic growth classes: hydrofobic, less-hygroscopic, more-hygroscopic and sea-salt. Similar classification has been earlier presented for Aitken and accumulation mode particles. In urban air, the summertime 10 nm particles showed varying less-hygroscopic growth behaviour, while winter time 10 nm and 20 nm particles were externally mixed with two different hygroscopic growth modes. The forest measurements revealed diurnal behaviour of hygroscopic growth, with high growth factors at day time and lower during night. The urban background particles had growth behaviour similar to the urban and forest measurement sites depending on the origin of the observed particles. The coastal measurements were strongly affected by air mass history. Both 10 nm and 20 nm particles were hygroscopic in marine background air. The 10 nm particles produced during clean nucleation burst periods were hydrofobic. Diurnal variation and higher growth factors of 10 nm particles were observed in air affected by other source regions. External mixing was occasionally observed at all the sites, but incidents with more than two growth modes were extremely rare.

  1. Size control in the synthesis of 1-6 nm gold nanoparticles via solvent-controlled nucleation.

    Science.gov (United States)

    Song, Jieun; Kim, Dukhan; Lee, Dongil

    2011-11-15

    We report a facile synthetic route for size-controlled preparation of gold nanoparticles. Nearly monodisperse gold nanoparticles with core diameters of 1-6 nm were obtained by reducing AuP(Phenyl)(3)Cl with tert-butylamine borane in the presence of dodecanethiol in the solvent mixture of benzene and CHCl(3). Mechanism studies have shown that the size control is achieved by the solvent-controlled nucleation in which the nuclei concentration increases with increasing the fraction of CHCl(3), leading to smaller particles. It was also found that, following the solvent-controlled nucleation, particle growth occurs via ligand replacement of PPh(3) on the nuclei by Au(I)thiolate generated by the digestive etching of small particles. This synthetic strategy was successfully demonstrated with other alkanethiols of different chain length with which size-controlled, monodisperse gold nanoparticles were prepared in remarkable yield without requiring any postsynthesis treatments.

  2. TEM investigations of laser ablated particles

    International Nuclear Information System (INIS)

    Fliegel, D.; Dundas, S.; Kosler, J.; Klementova, M.

    2009-01-01

    Full text: Laser ablation inductively coupled plasma mass spectrometry suffers from fractionation effects hindering a non matrix matched calibration strategy. Different reasons for elemental fractionation that are related to the laser ablation, the transport and the vaporization in the plasma are discussed. One major question to be addressed linked to the vaporization yield in the ICP is in which of mineralogical phase the different ablated particle sizes enter the plasma. This contribution will investigate particles generated by a 213 nm laser from different samples such as minerals and alloys with respect to their chemical and phase compositions using high resolution TEM. (author)

  3. Carbonaceous Particles Production in a Sputtering Discharge

    International Nuclear Information System (INIS)

    Dominique, Claire; Sant, Marco; Arnas, Cecile

    2005-01-01

    Spherical dust particles have been produced in argon glow discharge by sputtering of a graphite cathode. Their size varies from 40 to 200 nm depending on the distance between the two electrodes and the largest ones have a cauliflower shape. Simulations giving the evolution of the energy distribution of sputtered carbon atoms suggest a mechanism of growth by carbon vapour condensation. The chemical composition and structure of particles have been investigated by infrared spectroscopy and appear to be a complex arrangement of the carbon atoms and hetero-atoms

  4. On spin-canting in maghemite particles

    DEFF Research Database (Denmark)

    Linderoth, Søren; Hendriksen, Peter Vang; Bødker, F.

    1994-01-01

    The degree of alignment of the magnetic moments of Fe3+ ions in ultrafine maghemite particles has been studied in samples with induced magnetic texture. The textured samples were prepared by freezing ferrofluids, containing 7.5 nm maghemite particles, in a magnetic field. Mössbauer spectroscopy...... studies of the textured samples in large magnetic fields demonstrate that the lack of full alignment is not an effect of large magnetic anisotropy, as suggested recently, but that the effect is rather due to canting of individual spins. Journal of Applied Physics is copyrighted by The American Institute...

  5. High-temperature LDV seed particle development

    Science.gov (United States)

    Frish, Michael B.; Pierce, Vicky G.

    1989-05-01

    The feasibility of developing a method for making monodisperse, unagglomerated spherical particles greater than 50 nm in diameter was demonstrated. Carbonaceous particles were made by pyrolyzing ethylene with a pulsed CO2 laser, thereby creating a non-equilibrium mixture of carbon, hydrogen, hydrocarbon vapors, and unpyrolyzed ethylene. Via a complex series of reactions, the carbon and hydrocarbon vapors quickly condensed into the spherical particles. By cooling and dispersing them in a supersonic expansion immediately after their creation, the hot newly-formed spheres were prevented from colliding and coalescing, thus preventing the problem of agglomeration which as plagued other investigators studying laser-simulated particle formation. The cold particles could be left suspended in the residual gases indefinitely without agglomerating. Their uniform sizes and unagglomerated nature were visualized by collecting the particles on filters that were subsequently examined using electron microscopy. It was found the mean particle size can be coarsely controlled by varying the initial ethylene pressure, and can be finely controlled by varying the fluence (energy/unit area) with which the laser irradiates the gas. The motivating application for this research was to manufacture particles that could be used as laser Doppler velocimetry (LDV) seeds in high-temperature high-speed flows. Though the particles made in this program will not evaporate until heated to about 3000 K, and thus could serve as LDV seeds in some applications, they are not ideal when the hot atmosphere is also oxidizing. In that situation, ceramic materials would be preferable. Research performed elsewhere has demonstrated that selected ceramic materials can be manufactured by laser pyrolysis of appropriate supply gases. It is anticipated that, when the same gases are used in conjunction with the rapid cooling technique, unagglomerated spherical ceramic particles can be made with little difficulty. Such

  6. Study of drain-extended NMOS under electrostatic discharge stress in 28 nm and 40 nm CMOS process

    Science.gov (United States)

    Wang, Weihuai; Jin, Hao; Dong, Shurong; Zhong, Lei; Han, Yan

    2016-02-01

    Researches on the electrostatic discharge (ESD) performance of drain-extended NMOS (DeNMOS) under the state-of-the-art 28 nm and 40 nm bulk CMOS process are performed in this paper. Three distinguishing phases of avalanche breakdown stage, depletion region push-out stage and parasitic NPN turn on stage of the gate-grounded DeNMOS (GG-DeNMOS) fabricated under 28 nm CMOS process measured with transmission line pulsing (TLP) test are analyzed through TCAD simulations and tape-out silicon verification detailedly. Damage mechanisms and failure spots of GG-DeNMOS under both CMOS processes are thermal breakdown of drain junction. Improvements based on the basic structure adjustments can increase the GG-DeNMOS robustness from original 2.87 mA/μm to the highest 5.41 mA/μm. Under 40 nm process, parameter adjustments based on the basic structure have no significant benefits on the robustness improvements. By inserting P+ segments in the N+ implantation of drain or an entire P+ strip between the N+ implantation of drain and polysilicon gate to form the typical DeMOS-SCR (silicon-controlled rectifier) structure, the ESD robustness can be enhanced from 1.83 mA/μm to 8.79 mA/μm and 29.78 mA/μm, respectively.

  7. Cryogenic Lifetime Studies of 130 nm and 65 nm CMOS Technologies for High-Energy Physics Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, James R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Deptuch, G. W. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Wu, Guoying [Southern Methodist Univ., Dallas, TX (United States); Gui, Ping [Southern Methodist Univ., Dallas, TX (United States)

    2015-06-04

    The Long Baseline Neutrino Facility intends to use unprecedented volumes of liquid argon to fill a time projection chamber in an underground facility. Research is under way to place the electronics inside the cryostat. For reasons of efficiency and economics, the lifetimes of these circuits must be well in excess of 20 years. The principle mechanism for lifetime degradation of MOSFET devices and circuits operating at cryogenic temperatures is hot carrier degradation. Choosing a process technology that is, as much as possible, immune to such degradation and developing design techniques to avoid exposure to such damage are the goals. This, then, requires careful investigation and a basic understanding of the mechanisms that underlie hot carrier degradation and the secondary effects they cause in circuits. In this work, commercially available 130 nm and 65 nm nMOS transistors operating at cryogenic temperatures are investigated. Our results show that both technologies achieve the lifetimes required by the experiment. Minimal design changes are necessary in the case of the 130 nm process and no changes whatsoever are necessary for the 65 nm process.

  8. Sonochemical synthesis of silica particles and their size control

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hwa-Min [Advanced Materials and Chemical Engineering, Catholic University of Daegu, Gyeongbuk 38430 (Korea, Republic of); Lee, Chang-Hyun [Electronic and Electrical Engineering, Catholic University of Daegu, Gyeongbuk 38430 (Korea, Republic of); Kim, Bonghwan, E-mail: bhkim@cu.ac.kr [Electronic and Electrical Engineering, Catholic University of Daegu, Gyeongbuk 38430 (Korea, Republic of)

    2016-09-01

    Graphical abstract: - Highlights: • Silica particles were easily prepared by an ultrasound-assisted sol–gel method. • The particle size was controlled by the ammonium hydroxide/water molar ratio. • The size-controlled diameter of silica particles ranged from 40 to 400 nm. • The particles were formed in a relatively short reaction time. - Abstract: Using an ultrasound-assisted sol–gel method, we successfully synthesized very uniformly shaped, monodisperse, and size-controlled spherical silica particles from a mixture of ethanol, water, and tetraethyl orthosilicate in the presence of ammonia as catalyst, at room temperature. The diameters of the silica particles were distributed in the range from 40 to 400 nm; their morphology was well characterized by scanning electron microscopy. The silica particle size could be adjusted by choosing suitable concentrations of ammonium hydroxide and water, which in turn determined the nucleation and growth rates of the particles during the reaction. This sonochemical-based silica synthesis offers an alternative way to produce spherical silica particles in a relatively short reaction time. Thus, we suggest that this simple, low-cost, and efficient method of preparing uniform silica particles of various sizes will have practical and wide-ranging industrial applicability.

  9. Synthesis of Nm-PHB (nanomelanin-polyhydroxy butyrate) nanocomposite film and its protective effect against biofilm-forming multi drug resistant Staphylococcus aureus.

    Science.gov (United States)

    Kiran, George Seghal; Jackson, Stephen A; Priyadharsini, Sethu; Dobson, Alan D W; Selvin, Joseph

    2017-08-22

    Melanin is a dark brown ubiquitous photosynthetic pigment which have many varied and ever expanding applications in fabrication of radio-protective materials, food packaging, cosmetics and in medicine. In this study, melanin production in a Pseudomonas sp. which was isolated from the marine sponge Tetyrina citirna was optimized employing one-factor at a time experiments and characterized for chemical nature and stability. Following sonication nucleated nanomelanin (Nm) particles were formed and evaluated for antibacterial and antioxidant properties. Nanocomposite film was fabricated using combinations (% w/v) of polyhydroxy butyrate-nanomelanin (PHB:Nm) blended with 1% glycerol. The Nm was found to be spherical in shape with a diameter of 100-140 nm and showed strong antimicrobial activity against both Gram positive and Gram negative bacteria. The Nm-PHB nanocomposite film was homogeneous, smooth, without any cracks, and flexible. XRD and DSC data indicated that the film was crystalline in nature, and was thermostable up to 281.87 °C. This study represents the first report on the synthesis of Nm and fabrication of Nm-PHB nanocomposite film which show strong protective effect against multidrug resistant Staphyloccoccus aureus. Thus this Nm-PHB nanocomposite film may find utility as packaging material for food products by protecting the food products from oxidation and bacterial contamination.

  10. CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

    Directory of Open Access Journals (Sweden)

    S. S. Hings

    2008-07-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (dm<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (dcore≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

  11. Advanced Characterization: 3D chemistry and structure at sub-nm resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kotula, Paul Gabriel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rye, Michael J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-10-01

    This work has started the process of extending nanometer-scale comprehensive microanalysis to the 3rd dimension by combining full x-ray spectral imaging with previously developed computed tomography techniques whereby we acquire a series of spectral images for a large number of projections of the same specimen in the transmission electron microscope and then analyze the composite computed tomographic spectral image data prior to application of existing tomographic reconstruction software. We have demonstrated a needle-shaped specimen geometry (shape/size and preparation method) by focused ion beam preparation and acquisition and analysis of a complete tomographic spectral image on a test material consisting of fine-grained Ni with sub-10 nm alumina particles.

  12. Development of scalable frequency and power Phase-Locked Loop in 130nm CMOS technology

    CERN Document Server

    Firlej, M; Idzik, M; Moron, J; Swientek, K

    2014-01-01

    The design and measurements results of a prototype very low power Phase-Locked Loop (PLL) ASIC for applications in readout systems of particle physics detectors are presented. The PLL was fabricated in 130 nm CMOS technology. It was designed and simulated for frequency range 10 MHz–3.5 GHz. Four division factors i.e. 6, 8, 10 and 16 were implemented in the PLL feedback loop. The main PLL block-voltage controlled oscillator (VCO) should work in 16 frequency ranges/modes, switched either manually or automatically. Preliminary measurements done in frequency range 20 MHz–1.6 GHz showed that the ASIC is functional and generates proper clock signal. The automatic VCO mode switching, one of the main design goals, was positively verified. Power consumption of around 0.6mW was measured at 1 GHz for a division factor equal to 10.

  13. Development of scalable frequency and power Phase-Locked Loop in 130 nm CMOS technology

    International Nuclear Information System (INIS)

    Firlej, M; Fiutowski, T; Idzik, M; Moroń, J; Świentek, K

    2014-01-01

    The design and measurements results of a prototype very low power Phase-Locked Loop (PLL) ASIC for applications in readout systems of particle physics detectors are presented. The PLL was fabricated in 130 nm CMOS technology. It was designed and simulated for frequency range 10 MHz–3.5 GHz. Four division factors i.e. 6, 8, 10 and 16 were implemented in the PLL feedback loop. The main PLL block-voltage controlled oscillator (VCO) should work in 16 frequency ranges/modes, switched either manually or automatically. Preliminary measurements done in frequency range 20 MHz–1.6 GHz showed that the ASIC is functional and generates proper clock signal. The automatic VCO mode switching, one of the main design goals, was positively verified. Power consumption of around 0.6 mW was measured at 1 GHz for a division factor equal to 10

  14. Structural distortions in 5-10 nm silver nanoparticles under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Koski, Kristie J.; Kamp, Noelle M.; Kunz, Martin; Knight, Jason K.; Alivisatos, A.P.; Smith, R.K.

    2008-10-13

    We present experimental evidence that silver nanoparticles in the size range of 5-10 nm undergo a reversible structural transformation under hydrostatic pressures up to 10 GPa. We have used x-ray diffraction with a synchrotron light source to investigate pressure-dependent and size-dependent trends in the crystal structure of silver nanoparticles in a hydrostatic medium compressed in a diamond-anvil cell. Results suggest a reversible linear pressure-dependent rhombohedral distortion which has not been previously observed in bulk silver. We propose a mechanism for this transition that considers the bond-length distribution in idealized multiply twinned icosahedral particles. To further support this hypothesis, we also show that similar measurements of single-crystal platinum nanoparticles reveal no such distortions.

  15. Characterization and corrosion behavior of F6NM stainless steel treated in high temperature water

    Science.gov (United States)

    Li, Zheng-yang; Cai, Zhen-bing; Yang, Wen-jin; Shen, Xiao-yao; Xue, Guo-hong; Zhu, Min-hao

    2018-03-01

    F6NM martensitic stainless steel was exposed to 350 °C water condition for 500, 1500, and 2500 h to simulate pressurized water reactor (PWR) condition. The characterization and corrosion behavior of the oxide film were investigated. Results indicate that the exposed steel surface formed a double-layer oxide film. The outer oxide film is Fe-rich and contains two type oxide particles. However, the inner oxide film is Cr-rich, and two oxide films, whose thicknesses increase with increasing exposure time. The oxide film reduces the corrosion behavior because the outer oxide film has many crack and pores. Finally, the mechanism and factors affecting the formation of the oxide film were investigated.

  16. Radiation hard pixel sensors using high-resistive wafers in a 150 nm CMOS processing line

    Science.gov (United States)

    Pohl, D.-L.; Hemperek, T.; Caicedo, I.; Gonella, L.; Hügging, F.; Janssen, J.; Krüger, H.; Macchiolo, A.; Owtscharenko, N.; Vigani, L.; Wermes, N.

    2017-06-01

    Pixel sensors using 8'' CMOS processing technology have been designed and characterized offering the benefits of industrial sensor fabrication, including large wafers, high throughput and yield, as well as low cost. The pixel sensors are produced using a 150 nm CMOS technology offered by LFoundry in Avezzano. The technology provides multiple metal and polysilicon layers, as well as metal-insulator-metal capacitors that can be employed for AC-coupling and redistribution layers. Several prototypes were fabricated and are characterized with minimum ionizing particles before and after irradiation to fluences up to 1.1 × 1015 neq cm-2. The CMOS-fabricated sensors perform equally well as standard pixel sensors in terms of noise and hit detection efficiency. AC-coupled sensors even reach 100% hit efficiency in a 3.2 GeV electron beam before irradiation.

  17. Electroless synthesis of 3 nm wide alloy nanowires inside Tobacco mosaic virus

    International Nuclear Information System (INIS)

    Balci, Sinan; Kern, Klaus; Bittner, Alexander M; Hahn, Kersten; Kopold, Peter; Kadri, Anan; Wege, Christina

    2012-01-01

    We show that 3 nm wide cobalt–iron alloy nanowires can be synthesized by simple wet chemical electroless deposition inside tubular Tobacco mosaic virus particles. The method is based on adsorption of Pd(II) ions, formation of a Pd catalyst, and autocatalytic deposition of the alloy from dissolved metal salts, reduced by a borane compound. Extensive energy-filtering TEM investigations at the nanoscale revealed that the synthesized wires are alloys of Co, Fe, and Ni. We confirmed by high-resolution TEM that our alloy nanowires are at least partially crystalline, which is compatible with typical Co-rich alloys. Ni traces bestow higher stability, presumably against corrosion, as also known from bulk CoFe. Alloy nanowires, as small as the ones presented here, might be used for a variety of applications including high density data storage, imaging, sensing, and even drug delivery. (paper)

  18. Online single particle analysis of ice particle residuals from mountain-top mixed-phase clouds using laboratory derived particle type assignment

    Science.gov (United States)

    Schmidt, Susan; Schneider, Johannes; Klimach, Thomas; Mertes, Stephan; Schenk, Ludwig Paul; Kupiszewski, Piotr; Curtius, Joachim; Borrmann, Stephan

    2017-01-01

    In situ single particle analysis of ice particle residuals (IPRs) and out-of-cloud aerosol particles was conducted by means of laser ablation mass spectrometry during the intensive INUIT-JFJ/CLACE campaign at the high alpine research station Jungfraujoch (3580 m a.s.l.) in January-February 2013. During the 4-week campaign more than 70 000 out-of-cloud aerosol particles and 595 IPRs were analyzed covering a particle size diameter range from 100 nm to 3 µm. The IPRs were sampled during 273 h while the station was covered by mixed-phase clouds at ambient temperatures between -27 and -6 °C. The identification of particle types is based on laboratory studies of different types of biological, mineral and anthropogenic aerosol particles. The outcome of these laboratory studies was characteristic marker peaks for each investigated particle type. These marker peaks were applied to the field data. In the sampled IPRs we identified a larger number fraction of primary aerosol particles, like soil dust (13 ± 5 %) and minerals (11 ± 5 %), in comparison to out-of-cloud aerosol particles (2.4 ± 0.4 and 0.4 ± 0.1 %, respectively). Additionally, anthropogenic aerosol particles, such as particles from industrial emissions and lead-containing particles, were found to be more abundant in the IPRs than in the out-of-cloud aerosol. In the out-of-cloud aerosol we identified a large fraction of aged particles (31 ± 5 %), including organic material and secondary inorganics, whereas this particle type was much less abundant (2.7 ± 1.3 %) in the IPRs. In a selected subset of the data where a direct comparison between out-of-cloud aerosol particles and IPRs in air masses with similar origin was possible, a pronounced enhancement of biological particles was found in the IPRs.

  19. Unipolar and bipolar diffusion charging of ultrafine particles

    International Nuclear Information System (INIS)

    Adachi, Motoaki; Okuyama, Kikuo; Kousaka, Yasuo.

    1985-01-01

    Unipolar and bipolar diffusion charging of monodisperse ultrafine particles of 4 - 100 nm in diameter has been studied experimentally and theoretically. The particles were charged by unipolar and bipolar ions generated by α-ray irradiation and the charge distribution of particles was directly observed in the electric field after the growth of them by condensation of di-butyl phthalate vapor. In both cases of unipolar and bipolar charging, the experimental results have been found in good agreement with the solution of basic equations where Fuchs' formula is used as the combination probability of an ion with a particle. (author)

  20. Chemical vapour deposition of freestanding sub-60 nm graphene gyroids

    Science.gov (United States)

    Cebo, Tomasz; Aria, Adrianus I.; Dolan, James A.; Weatherup, Robert S.; Nakanishi, Kenichi; Kidambi, Piran R.; Divitini, Giorgio; Ducati, Caterina; Steiner, Ullrich; Hofmann, Stephan

    2017-12-01

    The direct chemical vapour deposition of freestanding graphene gyroids with controlled sub-60 nm unit cell sizes is demonstrated. Three-dimensional (3D) nickel templates were fabricated through electrodeposition into a selectively voided triblock terpolymer. The high temperature instability of sub-micron unit cell structures was effectively addressed through the early introduction of the carbon precursor, which stabilizes the metallized gyroidal templates. The as-grown graphene gyroids are self-supporting and can be transferred onto a variety of substrates. Furthermore, they represent the smallest free standing periodic graphene 3D structures yet produced with a pore size of tens of nm, as analysed by electron microscopy and optical spectroscopy. We discuss generality of our methodology for the synthesis of other types of nanoscale, 3D graphene assemblies, and the transferability of this approach to other 2D materials.

  1. Single, composite, and ceramic Nd:YAG 946-nm lasers

    Science.gov (United States)

    Lan, Rui-Jun; Yang, Guang; Zheng-Ping, Wang

    2015-06-01

    Single, composite crystal and ceramic continuous wave (CW) 946-nm Nd:YAG lasers are demonstrated, respectively. The ceramic laser behaves better than the crystal laser. With 5-mm long ceramic, a CW output power of 1.46 W is generated with an optical conversion efficiency of 13.9%, while the slope efficiency is 17.9%. The optimal ceramic length for a 946-nm laser is also calculated. Project supported by the National Natural Science Foundation of China (Grant No. 61405171), the Natural Science Foundation of Shandong Province, China (Grant No. ZR2012FQ014), and the Science and Technology Program of the Shandong Higher Education Institutions of China (Grant No. J13LJ05).

  2. Blue laser diode (450 nm) systems for welding copper

    Science.gov (United States)

    Silva Sa, M.; Finuf, M.; Fritz, R.; Tucker, J.; Pelaprat, J.-M.; Zediker, M. S.

    2018-02-01

    This paper will discuss the development of high power blue laser systems for industrial applications. The key development enabling high power blue laser systems is the emergence of high power, high brightness laser diodes at 450 nm. These devices have a high individual brightness rivaling their IR counterparts and they have the potential to exceed their performance and price barriers. They also have a very high To resulting in a 0.04 nm/°C wavelength shift. They have a very stable lateral far-field profile which can be combined with other diodes to achieve a superior brightness. This paper will report on the characteristics of the blue laser diodes, their integration into a modular laser system suitable for scaling the output power to the 1 kW level and beyond. Test results will be presented for welding of copper with power levels ranging from 150 Watts to 600 Watts

  3. A new hybrid evolutionary algorithm based on new fuzzy adaptive PSO and NM algorithms for Distribution Feeder Reconfiguration

    International Nuclear Information System (INIS)

    Niknam, Taher; Azadfarsani, Ehsan; Jabbari, Masoud

    2012-01-01

    Highlights: ► Network reconfiguration is a very important way to save the electrical energy. ► This paper proposes a new algorithm to solve the DFR. ► The algorithm combines NFAPSO with NM. ► The proposed algorithm is tested on two distribution test feeders. - Abstract: Network reconfiguration for loss reduction in distribution system is a very important way to save the electrical energy. This paper proposes a new hybrid evolutionary algorithm to solve the Distribution Feeder Reconfiguration problem (DFR). The algorithm is based on combination of a New Fuzzy Adaptive Particle Swarm Optimization (NFAPSO) and Nelder–Mead simplex search method (NM) called NFAPSO–NM. In the proposed algorithm, a new fuzzy adaptive particle swarm optimization includes two parts. The first part is Fuzzy Adaptive Binary Particle Swarm Optimization (FABPSO) that determines the status of tie switches (open or close) and second part is Fuzzy Adaptive Discrete Particle Swarm Optimization (FADPSO) that determines the sectionalizing switch number. In other side, due to the results of binary PSO(BPSO) and discrete PSO(DPSO) algorithms highly depends on the values of their parameters such as the inertia weight and learning factors, a fuzzy system is employed to adaptively adjust the parameters during the search process. Moreover, the Nelder–Mead simplex search method is combined with the NFAPSO algorithm to improve its performance. Finally, the proposed algorithm is tested on two distribution test feeders. The results of simulation show that the proposed method is very powerful and guarantees to obtain the global optimization.

  4. Photodissociation of the OD radical at 226 and 243 nm

    International Nuclear Information System (INIS)

    Radenovic, Dragana C.; Roij, Andre J.A. van; Chestakov, Dmitri A.; Eppink, Andre T.J.B.; Meulen, J.J. ter; Parker, David H.; Loo, Mark P.J. van der; Groenenboom, Gerrit C.; Greenslade, Margaret E.; Lester, Marsha I.

    2003-01-01

    The photodissociation dynamics of state selected OD radicals has been examined at 243 and 226 nm using velocity map imaging to probe the angle-speed distributions of the D( 2 S) and O( 3 P 2 ) products. Both experiment and complementary first principle calculations demonstrate that photodissociation occurs by promotion of OD from high vibrational levels of the ground X 2 Π state to the repulsive 1 2 Σ - state

  5. Writable and erasable PPV medium by irradiation at 365 nm

    Energy Technology Data Exchange (ETDEWEB)

    Mochizuki, Hiroyuki [Photonics Research Institutes, National Institute of Advanced Industrial Science and Technology, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)], E-mail: h-mochizuki@aist.go.jp; Mizokuro, Toshiko; Tanigaki, Nobutaka; Hiraga, Takashi [Photonics Research Institutes, National Institute of Advanced Industrial Science and Technology, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2008-03-03

    Dopings of vaporized cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl) ethane (CMTE) into poly(methyl methacrylate) (PMMA), polystyrene, and polycarbonate were performed by a vacuum process, and the doping behaviors of CMTE were evaluated. Among the matrix polymers, PMMA was dispersed CMTE densely in its surface region. By using the CMTE-doped PMMA, we could fabricate a novel rewritable medium: a multi-layered film was prepared from over-coating of CMTE-doped PMMA onto poly(p-phenylene vinylene) (PPV) film, which set on a transparent substrate. Image storage could be performed upon irradiation at 365 nm at the side of CMTE/PMMA layer: color of the irradiated area changed a light yellow to a red due to photo-isomerization of CMTE. Next, upon irradiation at 365 nm at the side of the transparent substrate, PPV emitted a green fluorescence at around 530 nm, and the CMTE absorbed the emission from PPV causing image-erasure based on back-isomerization of CMTE.

  6. Advanced CMOS device technologies for 45 nm node and below

    Directory of Open Access Journals (Sweden)

    A. Veloso, T. Hoffmann, A. Lauwers, H. Yu, S. Severi, E. Augendre, S. Kubicek, P. Verheyen, N. Collaert, P. Absil, M. Jurczak and S. Biesemans

    2007-01-01

    Full Text Available We review and discuss the latest developments and technology options for 45 nm node and below, with scaled planar bulk MOSFETs and MuGFETs as emerging devices. One of the main metal gate (MG candidates for scaled CMOS technologies are fully silicided (FUSI gates. In this work, by means of a selective and controlled poly etch-back integration process, dual work-function Ni-based FUSI/HfSiON CMOS circuits with record ring oscillator performance (high-VT are reported (17 ps at VDD=1.1 V and 20 pA/μm Ioff, meeting the ITRS 45 nm node requirement for low-power (LP CMOS. Compatibility of FUSI and other MG with known stress boosters like stressed CESL (contact-etch-stop-layer with high intrinsic stress or embedded SiGe in the pMOS S/D regions is validated. To obtain MuGFET devices that are competitive, as compared to conventional planar bulk devices, and that meet the stringent drive and leakage current requirements for the 32 nm node and beyond, higher channel mobilities are required. Results obtained by several strain engineering methods are presented here.

  7. Water line positions in the 782–840 nm region

    International Nuclear Information System (INIS)

    Hu, S.-M.; Chen, B.; Tan, Y.; Wang, J.; Cheng, C.-F.; Liu, A.-W.

    2015-01-01

    A set of water transitions in the 782–840 nm region, including 38 H 2 16 O lines, 12 HD 16 O lines, and 30 D 2 16 O lines, were recorded with a cavity ring-down spectrometer calibrated using precise atomic lines. Absolute frequencies of the lines were determined with an accuracy of about 5 MHz. Systematic shifts were found in the line positions given in the HITRAN database and the upper energy levels given in recent MARVEL studies. - Highlights: • Cavity ring-down spectra of H 2 16 O, HD 16 O, and D 2 16 O lines in the 782–840 nm region were measured. • Absolute line positions of 80 water lines were determined with an accuracy of about 5 MHz. • The H 2 16 O positions given in HITRAN have a systematic shift of 0.001 cm −1 in the 796–840 nm region. • MARVEL D 2 16 O energies have a systematic deviation of about −0.008 cm −1

  8. Cultured Human Fibroblast Biostimulation Using a 940 nm Diode Laser

    Science.gov (United States)

    Illescas-Montes, Rebeca; Melguizo-Rodríguez, Lucía; Manzano-Moreno, Francisco Javier; García-Martínez, Olga; Ruiz, Concepción

    2017-01-01

    Background: Fibroblasts are the main cells involved in regeneration during wound healing. The objective was to determine the effect of 940 nm diode laser on cultured human fibroblasts using different irradiation regimens. Methods: The CCD-1064Sk human epithelial fibroblast cell line was treated with a 940 nm diode laser at different energy doses (power: 0.2–1 W and energy density: 1–7 J/cm2) using different transmission modes (continuous or pulsed). The effect on cell growth at 24 and 72 h post-treatment was examined by measuring the proliferative capacity, the impact on the cell cycle, and the effect on cell differentiation. Results: fibroblast proliferative capacity was increased at 24 and 72 h post-treatment as a function of the energy dose. The greatest increase was observed with a power of 0.2 or 0.5 W and energy density between 1 and 4 J/cm2; no difference was observed between continuous and pulsed modes. There were no significant differences in cell cycle between treated groups and controls. α-actin expression was increased by treatment, indicating enhanced cell differentiation. Conclusion: The 940 nm diode laser has biostimulating effects on fibroblasts, stimulating proliferative capacity and cell differentiation without altering the cell cycle. Further researches are necessary to explore its potential clinical usefulness in wound healing. PMID:28773152

  9. Photoacoustic imaging at 1064nm wavelength with exogenous contrast agents

    Science.gov (United States)

    Upputuri, Paul Kumar; Jiang, Yuyan; Pu, Kanyi; Pramanik, Manojit

    2018-02-01

    Photoacoustic (PA) imaging is a promising imaging modality for both preclinical research and clinical practices. Laser wavelengths in the first near infrared window (NIR-I, 650-950 nm) have been widely used for photoacoustic imaging. As compared with NIR-I window, scattering of photons by biological tissues is largely reduced in the second NIR (NIR-II) window, leading to enhanced imaging fidelity. However, the lack of biocompatible NIR-II absorbing exogenous agents prevented the use of this window for in vivo imaging. In recent years, few studies have been reported on photoacoustic imaging in NIR-II window using exogenous contrast agents. In this work, we discuss the recent work on PA imaging using 1064 nm wavelength, the fundamental of Nd:YAG laser, as an excitation wavelength. The PA imaging at 1064 nm is advantageous because of the low and homogeneous signal from tissue background, enabling high contrast in PA imaging when NIR-II absorbing contrast agents are employed.

  10. Ion transport in sub-5-nm graphene nanopores

    International Nuclear Information System (INIS)

    Suk, Myung E.; Aluru, N. R.

    2014-01-01

    Graphene nanopore is a promising device for single molecule sensing, including DNA bases, as its single atom thickness provides high spatial resolution. To attain high sensitivity, the size of the molecule should be comparable to the pore diameter. However, when the pore diameter approaches the size of the molecule, ion properties and dynamics may deviate from the bulk values and continuum analysis may not be accurate. In this paper, we investigate the static and dynamic properties of ions with and without an external voltage drop in sub-5-nm graphene nanopores using molecular dynamics simulations. Ion concentration in graphene nanopores sharply drops from the bulk concentration when the pore radius is smaller than 0.9 nm. Ion mobility in the pore is also smaller than bulk ion mobility due to the layered liquid structure in the pore-axial direction. Our results show that a continuum analysis can be appropriate when the pore radius is larger than 0.9 nm if pore conductivity is properly defined. Since many applications of graphene nanopores, such as DNA and protein sensing, involve ion transport, the results presented here will be useful not only in understanding the behavior of ion transport but also in designing bio-molecular sensors

  11. Advances in 193 nm excimer lasers for mass spectrometry applications

    Science.gov (United States)

    Delmdahl, Ralph; Esser, Hans-Gerd; Bonati, Guido

    2016-03-01

    Ongoing progress in mass analysis applications such as laser ablation inductively coupled mass spectrometry of solid samples and ultraviolet photoionization mediated sequencing of peptides and proteins is to a large extent driven by ultrashort wavelength excimer lasers at 193 nm. This paper will introduce the latest improvements achieved in the development of compact high repetition rate excimer lasers and elaborate on the impact on mass spectrometry instrumentation. Various performance and lifetime measurements obtained in a long-term endurance test over the course of 18 months will be shown and discussed in view of the laser source requirements of different mass spectrometry tasks. These sampling type applications are served by excimer lasers delivering pulsed 193 nm output of several mJ as well as fast repetition rates which are already approaching one Kilohertz. In order to open up the pathway from the laboratory to broader market industrial use, sufficient component lifetimes and long-term stable performance behavior have to be ensured. The obtained long-term results which will be presented are based on diverse 193 nm excimer laser tube improvements aiming at e.g. optimizing the gas flow dynamics and have extended the operational life the laser tube for the first time over several billion pulses even under high duty-cycle conditions.

  12. Photoelectron Emission Studies in CsBr at 257 nm

    International Nuclear Information System (INIS)

    Maldonado, Juan R.; Liu, Zhi; Sun, Yun; Pianetta, Piero A.; Pease, Fabian W.

    2006-01-01

    CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films

  13. Cultured Human Fibroblast Biostimulation Using a 940 nm Diode Laser

    Directory of Open Access Journals (Sweden)

    Rebeca Illescas-Montes

    2017-07-01

    Full Text Available Background: Fibroblasts are the main cells involved in regeneration during wound healing. The objective was to determine the effect of 940 nm diode laser on cultured human fibroblasts using different irradiation regimens. Methods: The CCD-1064Sk human epithelial fibroblast cell line was treated with a 940 nm diode laser at different energy doses (power: 0.2–1 W and energy density: 1–7 J/cm2 using different transmission modes (continuous or pulsed. The effect on cell growth at 24 and 72 h post-treatment was examined by measuring the proliferative capacity, the impact on the cell cycle, and the effect on cell differentiation. Results: fibroblast proliferative capacity was increased at 24 and 72 h post-treatment as a function of the energy dose. The greatest increase was observed with a power of 0.2 or 0.5 W and energy density between 1 and 4 J/cm2; no difference was observed between continuous and pulsed modes. There were no significant differences in cell cycle between treated groups and controls. α-actin expression was increased by treatment, indicating enhanced cell differentiation. Conclusion: The 940 nm diode laser has biostimulating effects on fibroblasts, stimulating proliferative capacity and cell differentiation without altering the cell cycle. Further researches are necessary to explore its potential clinical usefulness in wound healing.

  14. Advanced lithographic filtration and contamination control for 14nm node and beyond semiconductor processes

    Science.gov (United States)

    Varanasi, Rao; Mesawich, Michael; Connor, Patrick; Johnson, Lawrence

    2017-03-01

    Two versions of a specific 2nm rated filter containing filtration medium and all other components produced from high density polyethylene (HDPE), one subjected to standard cleaning, the other to specialized ultra-cleaning, were evaluated in terms of their cleanliness characteristics, and also defectivity of wafers processed with photoresist filtered through each. With respect to inherent cleanliness, the ultraclean version exhibited a 70% reduction in total metal extractables and 90% reduction in organics extractables compared to the standard clean version. In terms of particulate cleanliness, the ultraclean version achieved stability of effluent particles 30nm and larger in about half the time required by the standard clean version, also exhibiting effluent levels at stability almost 90% lower. In evaluating defectivity of blanket wafers processed with photoresist filtered through either version, initial defect density while using the ultraclean version was about half that observed when the standard clean version was in service, with defectivity also falling more rapidly during subsequent usage of the ultraclean version compared to the standard clean version. Similar behavior was observed for patterned wafers, where the enhanced defect reduction was primarily of bridging defects. The filter evaluation and actual process-oriented results demonstrate the extreme value in using filtration designed possessing the optimal intrinsic characteristics, but with further improvements possible through enhanced cleaning processes

  15. Ion projection lithography: November 2000 status and sub-70-nm prospects

    Science.gov (United States)

    Kaesmaier, Rainer; Wolter, Andreas; Loeschner, Hans; Schunck, Stefan

    2000-10-01

    Among all next generation lithography (NGL) options Ion Projection Lithography (IPL) offers the smallest (particle) wavelength of 5x10- 5nm (l00keV Helium ions). Thus, 4x reduction ion-optics has diffraction limits IOS) has been realized and assembled. In parallel to the PDT-IOS effort, at Leica Jena a test bench for a vertical vacuum 300mm-wafer stage has been realized. Operation of magnetic bearing supported stage movement has already been demonstrated. As ASML vacuum compatible optical wafer alignment system, with 3nm(3(sigma) ) precision demonstrated in air, has been integrated to this wafer test bench system recently. Parallel to the IPL tool development, Infineon Technologies Mask House and the Institute for Microelectronics Stuttgart are intensively working on the development of IPL stencil masks with success in producing 150mm and 200mm stencil masks as reported elsewhere. This paper is focused on information about the status of the PDT-IOS tool.

  16. Mass analysis of charged aerosol particles in NLC and PMSE during the ECOMA/MASS campaign

    Directory of Open Access Journals (Sweden)

    S. Robertson

    2009-03-01

    Full Text Available MASS (Mesospheric Aerosol Sampling Spectrometer is a multichannel mass spectrometer for charged aerosol particles, which was flown from the Andøya Rocket Range, Norway, through NLC and PMSE on 3 August 2007 and through PMSE on 6 August 2007. The eight-channel analyzers provided for the first time simultaneous measurements of the charge density residing on aerosol particles in four mass ranges, corresponding to ice particles with radii <0.5 nm (including ions, 0.5–1 nm, 1–2 nm, and >3 nm (approximately. Positive and negative particles were recorded on separate channels. Faraday rotation measurements provided electron density and a means of checking charge density measurements made by the spectrometer. Additional complementary measurements were made by rocket-borne dust impact detectors, electric field booms, a photometer and ground-based radar and lidar. The MASS data from the first flight showed negative charge number densities of 1500–3000 cm−3 for particles with radii >3 nm from 83–88 km approximately coincident with PMSE observed by the ALWIN radar and NLC observed by the ALOMAR lidar. For particles in the 1–2 nm range, number densities of positive and negative charge were similar in magnitude (~2000 cm−3 and for smaller particles, 0.5–1 nm in radius, positive charge was dominant. The occurrence of positive charge on the aerosol particles of the smallest size and predominately negative charge on the particles of largest size suggests that nucleation occurs on positive condensation nuclei and is followed by collection of negative charge during subsequent growth to larger size. Faraday rotation measurements show a bite-out in electron density that increases the time for positive aerosol particles to be neutralized and charged negatively. The larger particles (>3 nm are observed throughout the NLC region, 83–88 km, and the smaller particles are observed primarily at the high end of the range, 86–88 km

  17. Mass analysis of charged aerosol particles in NLC and PMSE during the ECOMA/MASS campaign

    Directory of Open Access Journals (Sweden)

    S. Robertson

    2009-03-01

    Full Text Available MASS (Mesospheric Aerosol Sampling Spectrometer is a multichannel mass spectrometer for charged aerosol particles, which was flown from the Andøya Rocket Range, Norway, through NLC and PMSE on 3 August 2007 and through PMSE on 6 August 2007. The eight-channel analyzers provided for the first time simultaneous measurements of the charge density residing on aerosol particles in four mass ranges, corresponding to ice particles with radii <0.5 nm (including ions, 0.5–1 nm, 1–2 nm, and >3 nm (approximately. Positive and negative particles were recorded on separate channels. Faraday rotation measurements provided electron density and a means of checking charge density measurements made by the spectrometer. Additional complementary measurements were made by rocket-borne dust impact detectors, electric field booms, a photometer and ground-based radar and lidar. The MASS data from the first flight showed negative charge number densities of 1500–3000 cm−3 for particles with radii >3 nm from 83–88 km approximately coincident with PMSE observed by the ALWIN radar and NLC observed by the ALOMAR lidar. For particles in the 1–2 nm range, number densities of positive and negative charge were similar in magnitude (~2000 cm−3 and for smaller particles, 0.5–1 nm in radius, positive charge was dominant. The occurrence of positive charge on the aerosol particles of the smallest size and predominately negative charge on the particles of largest size suggests that nucleation occurs on positive condensation nuclei and is followed by collection of negative charge during subsequent growth to larger size. Faraday rotation measurements show a bite-out in electron density that increases the time for positive aerosol particles to be neutralized and charged negatively. The larger particles (>3 nm are observed throughout the NLC region, 83–88 km, and the smaller particles are observed primarily at the high end of the range, 86–88 km. The second flight into

  18. The relations of particles

    International Nuclear Information System (INIS)

    Okun, L.B.

    1991-01-01

    This book presents papers on elementary particle physics, relations between various particles, and the connections between particle physics with other branches of physics. The papers include: Contemporary status and prospects of high-energy physics; Particle physics prospects; and High energy physics

  19. Particle adhesion and removal

    CERN Document Server

    Mittal, K L

    2015-01-01

    The book provides a comprehensive and easily accessible reference source covering all important aspects of particle adhesion and removal.  The core objective is to cover both fundamental and applied aspects of particle adhesion and removal with emphasis on recent developments.  Among the topics to be covered include: 1. Fundamentals of surface forces in particle adhesion and removal.2. Mechanisms of particle adhesion and removal.3. Experimental methods (e.g. AFM, SFA,SFM,IFM, etc.) to understand  particle-particle and particle-substrate interactions.4. Mechanics of adhesion of micro- and  n

  20. Nanoparticle growth by particle-phase chemistry

    Directory of Open Access Journals (Sweden)

    M. J. Apsokardu

    2018-02-01

    Full Text Available The ability of particle-phase chemistry to alter the molecular composition and enhance the growth rate of nanoparticles in the 2–100 nm diameter range is investigated through the use of a kinetic growth model. The molecular components included are sulfuric acid, ammonia, water, a non-volatile organic compound, and a semi-volatile organic compound. Molecular composition and growth rate are compared for particles that grow by partitioning alone vs. those that grow by a combination of partitioning and an accretion reaction in the particle phase between two organic molecules. Particle-phase chemistry causes a change in molecular composition that is particle diameter dependent, and when the reaction involves semi-volatile molecules, the particles grow faster than by partitioning alone. These effects are most pronounced for particles larger than about 20 nm in diameter. The modeling results provide a fundamental basis for understanding recent experimental measurements of the molecular composition of secondary organic aerosol showing that accretion reaction product formation increases linearly with increasing aerosol volume-to-surface-area. They also allow initial estimates of the reaction rate constants for these systems. For secondary aerosol produced by either OH oxidation of the cyclic dimethylsiloxane (D5 or ozonolysis of β-pinene, oligomerization rate constants on the order of 10−3 to 10−1 M−1 s−1 are needed to explain the experimental results. These values are consistent with previously measured rate constants for reactions of hydroperoxides and/or peroxyacids in the condensed phase.

  1. Review of particle properties. Particle Data Group

    International Nuclear Information System (INIS)

    1978-04-01

    This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Rev. Mod. Phys. 48 (1976) No. 2, Part II; and Supplement, Phys. Lett. 68B (1977) 1]. Data are evaluated, listed, averaged, and summarized in tables. Numerous tables, figures, and formulae of interest to particle physicists are also included. A data booklet is available

  2. A reflectivity profilometer for the optical characterisation of graded reflectivity mirrors in the 250 nm - 1100 nm spectral region

    International Nuclear Information System (INIS)

    Colucci, Alessandro; Nichelatti, Enrico

    1998-04-01

    It's developed the prototype of an instrument that can be used for the optical characterisation of graded reflectivity mirrors at any wavelength in the spectral region from 250 nm to 1100 nm. The instrument utilises a high-pressure Xe arc lamp as light source. Light is spectrally filtered by means of a grating monochromator. The sample is illuminated with an image of the monochromator exit slit. After reflection from the sample, this image is projected onto a 1024-elements charge-coupled device linear array driven by a digital frame board and interfaced with a personal computer. It's tested the instrument accuracy by comparing measurement results with the corresponding ones obtained by means of a laser scanning technique. Measurement Rms repeatability has been estimated to be approximately of 0.8% [it

  3. Combined fractional resurfacing (10600 nm/1540 nm): Tridimensional imaging evaluation of a new device for skin rejuvenation.

    Science.gov (United States)

    Mezzana, Paolo; Valeriani, Maurizio; Valeriani, Roberto

    2016-11-01

    In this study were described the results, by tridimensional imaging evaluation, of the new "Combined Fractional Resurfacing" technique with the first fractional laser that overtakes the limits of traditional ablative, nonablative fractional resurfacing by combining CO 2 ablative and GaAs nonablative lasers. These two wavelengths can work separately or in a mixed modality to give the best treatment choice to all the patients. In this study, it is demonstrated that the simultaneous combination of the CO 2 wavelength (10600 nm) and GaAs wavelength (1540 nm) reduced the downtime, reduced pain during the treatment, and produced better results on fine wrinkles reduction and almost the same results on pigmentation as seen with 3D analysis by Antera (Miravex).

  4. A reflectivity profilometer for the optical characterisation of grade reflectivity mirrors in the 250 nm - 1100 nm spectral region

    Energy Technology Data Exchange (ETDEWEB)

    Colucci, Alessandro; Nichelatti, Enrico [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione

    1998-04-01

    It`s developed the prototype of an instrument that can be used for the optical characterisation of graded reflectivity mirrors at any wavelength in the spectral region from 250 nm to 1100 nm. The instrument utilises a high-pressure Xe arc lamp as light source. Light is spectrally filtered by means of a grating monochromator. The sample is illuminated with an image of the monochromator exit slit. After reflection from the sample, this image is projected onto a 1024-elements charge-coupled device linear array driven by a digital frame board and interfaced with a personal computer. It`s tested the instrument accuracy by comparing measurement results with the corresponding ones obtained by means of a laser scanning technique. Measurement Rms repeatability has been estimated to be approximately of 0.8%. [Italiano] E` stato sviluppato il prototipo di uno strumento per la catatterizzazione ottica di specchi a riflettivita` variabile, operante a qualsiasi lunghezza d`onda nell`intervallo spettrale da 250 nm a 1100 nm. La sorgente dello strumento e` una lampada ad arco allo Xenon ad alta pressione. La luce e` filtrata spettralmente per mezzo di un monocromatore a reticolo. Il campione viene illuminato da un`immagine della fenditura d`uscita del monocromatore. Dopo essere stata riflessa dal campione, questa immagine viene proiettata su un array CCD lineare a 1024 elementi, connesso elettronicamente a una scheda digitale e interfacciato a un personal computer. L`accuratezza dello strumento e` stata verificata confrontando alcune misure con le corrispondenti misure ottenute mediante una tecnica a scansione laser. La ripetibilita` RMS delle misure e` stata stimata essere circa dello 0.8%.

  5. Detection of lead nanoparticles in game meat by single particle ICP-MS following use of lead-containing bullets

    DEFF Research Database (Denmark)

    Kollander, Barbro; Widemo, Fredrik; Ågren, Erik

    2017-01-01

    This study investigated whether game meat may contain nanoparticles of lead from ammunition. Lead nanoparticles in the range 40 to 750 nm were detected by ICP-MS in single particle mode in game shot with lead-containing bullets. The median diameter of the detected nanoparticles was around 60 nm....... The particle mass concentration ranged from 290 to 340 ng/g meat and the particle number concentrations from 27 to 50 million particles/g meat. The size limit of detection strongly depended on the level of dissolved lead and was in the range of 40 to 80 nm. In game meat sampled more than 10 cm away from...... the wound channel, no lead particles with a diameter larger than 40 nm were detected. In addition to dissolved lead in meat that originated from particulates, the presence of lead nano particles in game meat represents a hitherto unattended source of lead with a largely unknown toxicological impact...

  6. Mobility of Hematite Submicron Particles in Water Solutions of Sugar

    International Nuclear Information System (INIS)

    Fornal, P.; Stanek, J.

    2008-01-01

    The mobility of the 100 nm Fe 2 O 3 particles in dense water solutions of sugar (sucrose) was determined from the analysis of the resonance absorption line shape of the Moessbauer spectra recorded in the -5 o C to 40 o C temperature range for different sugar concentrations. The discrepancy between the experimental data and the prediction of the classical theory of Brownian movement are interpreted in the term of the short observation time and the interaction between the solid particles in fluids, which extends in water up to 300 nm. The sedimentation process in the studied colloids was observed. (authors)

  7. Size-resolved chemical composition, effective density, and optical properties of biomass burning particles

    Science.gov (United States)

    Zhai, Jinghao; Lu, Xiaohui; Li, Ling; Zhang, Qi; Zhang, Ci; Chen, Hong; Yang, Xin; Chen, Jianmin

    2017-06-01

    Biomass burning aerosol has an important impact on the global radiative budget. A better understanding of the correlations between the mixing states of biomass burning particles and their optical properties is the goal of a number of current studies. In this work, the effective density, chemical composition, and optical properties of rice straw burning particles in the size range of 50-400 nm were measured using a suite of online methods. We found that the major components of particles produced by burning rice straw included black carbon (BC), organic carbon (OC), and potassium salts, but the mixing states of particles were strongly size dependent. Particles of 50 nm had the smallest effective density (1.16 g cm-3) due to a relatively large proportion of aggregate BC. The average effective densities of 100-400 nm particles ranged from 1.35 to 1.51 g cm-3 with OC and inorganic salts as dominant components. Both density distribution and single-particle mass spectrometry showed more complex mixing states in larger particles. Upon heating, the separation of the effective density distribution modes confirmed the external mixing state of less-volatile BC or soot and potassium salts. The size-resolved optical properties of biomass burning particles were investigated at two wavelengths (λ = 450 and 530 nm). The single-scattering albedo (SSA) showed the lowest value for 50 nm particles (0.741 ± 0.007 and 0.889 ± 0.006) because of the larger proportion of BC content. Brown carbon played an important role for the SSA of 100-400 nm particles. The Ångström absorption exponent (AAE) values for all particles were above 1.6, indicating the significant presence of brown carbon in all sizes. Concurrent measurements in our work provide a basis for discussing the physicochemical properties of biomass burning aerosol and its effects on the global climate and atmospheric environment.

  8. Intra-cavity upconversion to 631 nm of images illuminated by an eye-safe ASE source at 1550 nm.

    Science.gov (United States)

    Torregrosa, A J; Maestre, H; Capmany, J

    2015-11-15

    We report an image wavelength upconversion system. The system mixes an incoming image at around 1550 nm (eye-safe region) illuminated by an amplified spontaneous emission (ASE) fiber source with a Gaussian beam at 1064 nm generated in a continuous-wave diode-pumped Nd(3+):GdVO(4) laser. Mixing takes place in a periodically poled lithium niobate (PPLN) crystal placed intra-cavity. The upconverted image obtained by sum-frequency mixing falls around the 631 nm red spectral region, well within the spectral response of standard silicon focal plane array bi-dimensional sensors, commonly used in charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) video cameras, and of most image intensifiers. The use of ASE illumination benefits from a noticeable increase in the field of view (FOV) that can be upconverted with regard to using coherent laser illumination. The upconverted power allows us to capture real-time video in a standard nonintensified CCD camera.

  9. 5.5nm wavelength-tunable high-power MOPA diode laser system at 971 nm

    Science.gov (United States)

    Tawfieq, Mahmoud; Müller, André; Fricke, Jörg; Della Casa, Pietro; Ressel, Peter; Ginolas, Arnim; Feise, David; Sumpf, Bernd; Tränkle, Günther

    2018-02-01

    In this work, a widely tunable hybrid master oscillator power amplifier (MOPA) diode laser with 6.2 W of output power at 971.8 nm will be presented. The MO is a DBR laser, with a micro heater embedded on top of the DBR grating for wavelength tunability. The emitted light of the MO is collimated and coupled into a tapered amplifier using micro cylindrical lenses, all constructed on a compact 25 mm × 25 mm conduction cooled laser package. The MOPA system emits light with a measured spectral width smaller than 17 pm, limited by the spectrometer, and with a beam propagation factor of M2 1/e2 = 1.3 in the slow axis. The emission is thus nearly diffraction limited with 79% of the total power within the central lobe (4.9 W diffraction limited). The electrically controlled micro-heater provides up to 5.5 nm of wavelength tunability, up to a wavelength of 977.3 nm, while maintaining an output power variation of only +/- 0.16 % for the entire tuning range.

  10. Novel 755-nm diode laser vs. conventional 755-nm scanned alexandrite laser: Side-by-side comparison pilot study for thorax and axillary hair removal.

    Science.gov (United States)

    Paasch, Uwe; Wagner, Justinus A; Paasch, Hartmut W

    2015-01-01

    Alexandrite (755 nm) and diode lasers (800-810 nm) are commonly used for hair removal. The alexandrite laser technology is somewhat cumbersome whereas new diode lasers are more robust. Recently, alexandrite-like 755 nm wavelength diodes became available. To compare the efficacy, tolerability, and subject satisfaction of a 755 nm diode laser operated in conventional (HR) and non-conventional in-motion (SHR) modes with a conventional scanned alexandrite 755 nm laser for chest and axillary hair removal. A prospective, single-center, proof of principle study was designed to evaluate the safety, efficacy and handling of a 755 nm diode laser system in comparison to a standard alexandrite 755 nm scanning hair removal laser. The new 755 nm diode is suitable to be used in SHR and HR mode and has been tested for its safety, efficacy and handling in a volunteer with success. Overall, both systems showed a high efficacy in hair reduction (88.8% 755 nm diode laser vs. 77.7% 755 nm alexandrite laser). Also, during the study period, no severe adverse effects were reported. The new 755 nm diode laser is as effective and safe as the traditional 755 nm alexandrite laser. Additionally, treatment with the 755 nm diode laser with HR and SHR modes was found to be less painful.

  11. Effect of tungsten metal particle sizes on the solubility of molten alloy melt: Experimental observation of Gibbs-Thomson effect in nanocomposites

    Science.gov (United States)

    Lee, M. H.; Das, J.; Sordelet, D. J.; Eckert, J.; Hurd, A. J.

    2012-09-01

    We investigated the effect of tungsten particle sizes on the thermal stability and reactivity of uniformly dispersed W particles in molten Hf-based alloy melt at elevated temperature (1673 K). The solubility of particles less than 100 nm in radius is significantly enhanced. In case of fine W particles with 20 nm diameter, their solubility increases remarkably around 700% compared to that of coarse micrometer-scale particles. The mechanisms and kinetics of this dynamic growth of particle are discussed as well as techniques developed to obtain frozen microstructure of particle-reinforced composites by rapid solidification.

  12. Inter-particle and interfacial interaction of magnetic nanoparticles

    International Nuclear Information System (INIS)

    Bae, Che Jin; Hwang, Yosun; Park, Jongnam; An, Kwangjin; Lee, Youjin; Lee, Jinwoo; Hyeon, Taeghwan; Park, J.-G.

    2007-01-01

    In order to understand inter-particle as well as interfacial interaction of magnetic nanoparticles, we have prepared several Fe 3 O 4 nanoparticles in the ranges from 3 to 50 nm. These nanoparticles are particularly well characterized in terms of size distribution with a standard deviation (σ) in size less than 0.4 nm. We investigated the inter-particle interaction by measuring the magnetic properties of the nanoparticles while controlling inter-particle distances by diluting the samples with solvents. According to this study, blocking temperatures dropped by 8-17 K with increasing the inter-particle distances from a few nm to 140 nm while the overall shape and qualitative behavior of the magnetization remain unchanged. It implies that most features observed in the magnetic properties of the nanoparticles are due to the intrinsic properties of the nanoparticles, not due to the inter-particle interaction. We then examined possible interfacial magnetic interaction in the core-shell structure of our Fe 3 O 4 nanoparticles

  13. Titanium Dioxide Particle Type and Concentration Influence the Inflammatory Response in Caco-2 Cells

    Science.gov (United States)

    Tada-Oikawa, Saeko; Ichihara, Gaku; Fukatsu, Hitomi; Shimanuki, Yuka; Tanaka, Natsuki; Watanabe, Eri; Suzuki, Yuka; Murakami, Masahiko; Izuoka, Kiyora; Chang, Jie; Wu, Wenting; Yamada, Yoshiji; Ichihara, Sahoko

    2016-01-01

    Titanium dioxide (TiO2) nanoparticles are widely used in cosmetics, sunscreens, biomedicine, and food products. When used as a food additive, TiO2 nanoparticles are used in significant amounts as white food-coloring agents. However, the effects of TiO2 nanoparticles on the gastrointestinal tract remain unclear. The present study was designed to determine the effects of five TiO2 particles of different crystal structures and sizes in human epithelial colorectal adenocarcinoma (Caco-2) cells and THP-1 monocyte-derived macrophages. Twenty-four-hour exposure to anatase (primary particle size: 50 and 100 nm) and rutile (50 nm) TiO2 particles reduced cellular viability in a dose-dependent manner in THP-1 macrophages, but in not Caco-2 cells. However, 72-h exposure of Caco-2 cells to anatase (50 nm) TiO2 particles reduced cellular viability in a dose-dependent manner. The highest dose (50 µg/mL) of anatase (100 nm), rutile (50 nm), and P25 TiO2 particles also reduced cellular viability in Caco-2 cells. The production of reactive oxygen species tended to increase in both types of cells, irrespective of the type of TiO2 particle. Exposure of THP-1 macrophages to 50 µg/mL of anatase (50 nm) TiO2 particles increased interleukin (IL)-1β expression level, and exposure of Caco-2 cells to 50 µg/mL of anatase (50 nm) TiO2 particles also increased IL-8 expression. The results indicated that anatase TiO2 nanoparticles induced inflammatory responses compared with other TiO2 particles. Further studies are required to determine the in vivo relevance of these findings to avoid the hazards of ingested particles. PMID:27092499

  14. Titanium Dioxide Particle Type and Concentration Influence the Inflammatory Response in Caco-2 Cells

    Directory of Open Access Journals (Sweden)

    Saeko Tada-Oikawa

    2016-04-01

    Full Text Available Titanium dioxide (TiO2 nanoparticles are widely used in cosmetics, sunscreens, biomedicine, and food products. When used as a food additive, TiO2 nanoparticles are used in significant amounts as white food-coloring agents. However, the effects of TiO2 nanoparticles on the gastrointestinal tract remain unclear. The present study was designed to determine the effects of five TiO2 particles of different crystal structures and sizes in human epithelial colorectal adenocarcinoma (Caco-2 cells and THP-1 monocyte-derived macrophages. Twenty-four-hour exposure to anatase (primary particle size: 50 and 100 nm and rutile (50 nm TiO2 particles reduced cellular viability in a dose-dependent manner in THP-1 macrophages, but in not Caco-2 cells. However, 72-h exposure of Caco-2 cells to anatase (50 nm TiO2 particles reduced cellular viability in a dose-dependent manner. The highest dose (50 µg/mL of anatase (100 nm, rutile (50 nm, and P25 TiO2 particles also reduced cellular viability in Caco-2 cells. The production of reactive oxygen species tended to increase in both types of cells, irrespective of the type of TiO2 particle. Exposure of THP-1 macrophages to 50 µg/mL of anatase (50 nm TiO2 particles increased interleukin (IL-1β expression level, and exposure of Caco-2 cells to 50 µg/mL of anatase (50 nm TiO2 particles also increased IL-8 expression. The results indicated that anatase TiO2 nanoparticles induced inflammatory responses compared with other TiO2 particles. Further studies are required to determine the in vivo relevance of these findings to avoid the hazards of ingested particles.

  15. Titanium Dioxide Particle Type and Concentration Influence the Inflammatory Response in Caco-2 Cells.

    Science.gov (United States)

    Tada-Oikawa, Saeko; Ichihara, Gaku; Fukatsu, Hitomi; Shimanuki, Yuka; Tanaka, Natsuki; Watanabe, Eri; Suzuki, Yuka; Murakami, Masahiko; Izuoka, Kiyora; Chang, Jie; Wu, Wenting; Yamada, Yoshiji; Ichihara, Sahoko

    2016-04-16

    Titanium dioxide (TiO₂) nanoparticles are widely used in cosmetics, sunscreens, biomedicine, and food products. When used as a food additive, TiO₂ nanoparticles are used in significant amounts as white food-coloring agents. However, the effects of TiO₂ nanoparticles on the gastrointestinal tract remain unclear. The present study was designed to determine the effects of five TiO₂ particles of different crystal structures and sizes in human epithelial colorectal adenocarcinoma (Caco-2) cells and THP-1 monocyte-derived macrophages. Twenty-four-hour exposure to anatase (primary particle size: 50 and 100 nm) and rutile (50 nm) TiO₂ particles reduced cellular viability in a dose-dependent manner in THP-1 macrophages, but in not Caco-2 cells. However, 72-h exposure of Caco-2 cells to anatase (50 nm) TiO₂ particles reduced cellular viability in a dose-dependent manner. The highest dose (50 µg/mL) of anatase (100 nm), rutile (50 nm), and P25 TiO₂ particles also reduced cellular viability in Caco-2 cells. The production of reactive oxygen species tended to increase in both types of cells, irrespective of the type of TiO₂ particle. Exposure of THP-1 macrophages to 50 µg/mL of anatase (50 nm) TiO₂ particles increased interleukin (IL)-1β expression level, and exposure of Caco-2 cells to 50 µg/mL of anatase (50 nm) TiO₂ particles also increased IL-8 expression. The results indicated that anatase TiO₂ nanoparticles induced inflammatory responses compared with other TiO₂ particles. Further studies are required to determine the in vivo relevance of these findings to avoid the hazards of ingested particles.

  16. Reduced nonlinearities in 100-nm high SOI waveguides

    Science.gov (United States)

    Lacava, C.; Marchetti, R.; Vitali, V.; Cristiani, I.; Giuliani, G.; Fournier, M.; Bernabe, S.; Minzioni, P.

    2016-03-01

    Here we show the results of an experimental analysis dedicated to investigate the impact of optical non linear effects, such as two-photon absorption (TPA), free-carrier absorption (FCA) and free-carrier dispersion (FCD), on the performance of integrated micro-resonator based filters for application in WDM telecommunication systems. The filters were fabricated using SOI (Silicon-on-Insulator) technology by CEA-Leti, in the frame of the FP7 Fabulous Project, which aims to develop low-cost and high-performance integrated optical devices to be used in new generation passive optical- networks (NG-PON2). Different designs were tested, including both ring-based structures and racetrack-based structures, with single-, double- or triple- resonator configuration, and using different waveguide cross-sections (from 500 x 200 nm to 825 x 100 nm). Measurements were carried out using an external cavity tunable laser source operating in the extended telecom bandwidth, using both continuous wave signals and 10 Gbit/s modulated signals. Results show that the use 100-nm high waveguide allows reducing the impact of non-linear losses, with respect to the standard waveguides, thus increasing by more than 3 dB the maximum amount of optical power that can be injected into the devices before causing significant non-linear effects. Measurements with OOK-modulated signals at 10 Gbit/s showed that TPA and FCA don't affect the back-to-back BER of the signal, even when long pseudo-random-bit-sequences (PRBS) are used, as the FCD-induced filter-detuning increases filter losses but "prevents" excessive signal degradation.

  17. All-dry resist processes for 193-nm lithography

    Science.gov (United States)

    Horn, Mark W.; Maxwell, Brian E.; Kunz, Roderick R.; Hibbs, Michael S.; Eriksen, Lynn M.; Palmateer, Susan C.; Forte, Anthony R.

    1995-06-01

    We report on two different all-dry resist schemes for 193-nm lithography, one negative tone and one positive tone. Our negative tone resist is an extension of our initial work on all-dry photoresists. This scheme employs a bilayer in which the imaging layer is formed by plasma enhanced chemical vapor deposition (PECVD) from tetramethylsilane (TMS) and deposited onto PECVD carbon-based planarizing layers. Figure 1 shows SEMs of dark field and light field octagons patterned in projection on Lincoln Laboratory's 0.5-NA 193-nm Micrascan system. These 0.225-micrometers and 0.200-micrometers line and space features were obtained at a dose of approximately 58 mJ/cm2. Dry development of the exposed resist was accomplished using Cl2 chemistry in a helicon high-ion-density etching tool. Pattern transfer was performed in the helicon tool with oxygen-based chemistries. Recently, we have also developed an all-dry positive-tone silylation photoresist. This photoresist is a PECVD carbon-based polymer which is crosslinked by 193-nm exposure, enabling selective silylation similar to that initially reported by Hartney et al., with spin-applied polymers. In those polymers, for example polyvinylphenol, the silylation site concentration is fixed by the hydroxyl groups on the polymer precursors, thus limiting the silicon uptake per unit volume. With PECVD polymers, the total concentration of silylation sites and their depth can be tailored by varying plasma species as a function of time during the deposition. This affords the possibility of greater silicon uptake per unit volume and better depth control of the silylation profile. Figure 2 shows a SEM of 0.5-micrometers features patterned in plasma deposited silylation resist.

  18. Emulsifier-free emulsion polymerization produces highly charged, monodisperse particles for near infrared photonic crystals.

    Science.gov (United States)

    Reese, Chad E; Asher, Sanford A

    2002-04-01

    We have developed emulsifier-free, emulsion polymerization recipes for the synthesis of highly charged, monodisperse latex particles of diameters between 500 and 1100 nm. These latexes consist of poly[styrene-(co-2-hydroxyethyl methacrylate)] spherical particles whose surfaces are functionalized with sulfate and carboxylic acid groups. These highly charged, monodisperse particles readily self-assemble into robust, three-dimensionally ordered crystalline colloidal array photonic crystals that Bragg diffract light in the near infrared spectral region. By altering the particle number density, the diffraction wavelength can be tuned from approximately 1000 to approximately 4000 nm.

  19. Polishing Sapphire Substrates by 355 nm Ultraviolet Laser

    Directory of Open Access Journals (Sweden)

    X. Wei

    2012-01-01

    Full Text Available This paper tries to investigate a novel polishing technology with high efficiency and nice surface quality for sapphire crystal that has high hardness, wear resistance, and chemical stability. A Q-switched 355 nm ultraviolet laser with nanosecond pulses was set up and used to polish sapphire substrate in different conditions in this paper. Surface roughness Ra of polished sapphire was measured with surface profiler, and the surface topography was observed with scanning electronic microscope. The effects of processing parameters as laser energy, pulse repetition rate, scanning speed, incident angle, scanning patterns, and initial surface conditions on surface roughness were analyzed.

  20. High bit rate germanium single photon detectors for 1310nm

    Science.gov (United States)

    Seamons, J. A.; Carroll, M. S.

    2008-04-01

    There is increasing interest in development of high speed, low noise and readily fieldable near infrared (NIR) single photon detectors. InGaAs/InP Avalanche photodiodes (APD) operated in Geiger mode (GM) are a leading choice for NIR due to their preeminence in optical networking. After-pulsing is, however, a primary challenge to operating InGaAs/InP single photon detectors at high frequencies1. After-pulsing is the effect of charge being released from traps that trigger false ("dark") counts. To overcome this problem, hold-off times between detection windows are used to allow the traps to discharge to suppress after-pulsing. The hold-off time represents, however, an upper limit on detection frequency that shows degradation beginning at frequencies of ~100 kHz in InGaAs/InP. Alternatively, germanium (Ge) single photon avalanche photodiodes (SPAD) have been reported to have more than an order of magnitude smaller charge trap densities than InGaAs/InP SPADs2, which allowed them to be successfully operated with passive quenching2 (i.e., no gated hold off times necessary), which is not possible with InGaAs/InP SPADs, indicating a much weaker dark count dependence on hold-off time consistent with fewer charge traps. Despite these encouraging results suggesting a possible higher operating frequency limit for Ge SPADs, little has been reported on Ge SPAD performance at high frequencies presumably because previous work with Ge SPADs has been discouraged by a strong demand to work at 1550 nm. NIR SPADs require cooling, which in the case of Ge SPADs dramatically reduces the quantum efficiency of the Ge at 1550 nm. Recently, however, advantages to working at 1310 nm have been suggested which combined with a need to increase quantum bit rates for quantum key distribution (QKD) motivates examination of Ge detectors performance at very high detection rates where InGaAs/InP does not perform as well. Presented in this paper are measurements of a commercially available Ge APD

  1. 5 nm structures produced by direct laser writing

    International Nuclear Information System (INIS)

    Pavel, E; Jinga, S; Andronescu, E; Vasile, B S; Rotiu, E; Ionescu, L; Mazilu, C

    2011-01-01

    Here we present a new approach to overcome the optical diffraction limit by using novel materials. In the paper, we report experimental results obtained by high-resolution transmission electron microscopy (HRTEM) and optical absorption spectroscopy, for a fluorescent photosensitive glass-ceramic containing rare-earth ions such as samarium (Sm). Using a home built dynamic tester, with a low power laser, we recorded nanostructures having 5 nm line widths. In the line structure, measurements reveal the presence of silver nanocrystals with few nanometre sizes. HRTEM shows that there is a random orientation of the nanocrystals. A writing mechanism with three steps is proposed.

  2. Comparison of a novel high-power blue diode laser (λ=442 nm) with Ho:YAG (λ=2100 nm), Tm fiber (λ=1940 nm), and KTP (λ=532 nm) lasers for soft tissue ablation

    Science.gov (United States)

    Vinnichenko, Victoriya; Kovalenko, Anastasiya; Arkhipova, Valeriya; Yaroslavsky, Ilya; Altshuler, Gregory; Gapontsev, Valentin

    2018-02-01

    Three lasers were directly compared, including the Ho:YAG laser (λ = 2100 nm), Tm fiber laser (λ = 1940 nm) operating in 3 different modes (CW, regular pulse, and super pulse), and blue diode laser (λ = 442 nm) for vaporization and coagulation efficiency for treating blood-rich soft tissues, ex vivo, in a porcine kidney model at quasi-contact cutting in water. In addition, experimental results were compared with published data on performance of KTP laser (λ = 532 nm) at similar experimental settings (Power = 60 W and cutting speed = 2 mm/s). Tm fiber laser in pulsed mode and blue laser produced highest vaporization rates of 3.7 and 3.4 mm3/s, respectively. Tm fiber laser (in both CW and pulsed modes) also produced the largest coagulation zone among the laser sources tested. A carbonization zone was observed for Tm fiber laser in CW and pulsed modes, as well as for the blue diode laser. Tm fiber laser in super-pulse mode and Ho:YAG laser both resulted in irregular coagulation zones without carbonization. Comparison with known data for KTP laser revealed that tissue effects of the blue laser are similar to that of the KTP laser. These results suggest that the combination of the two lasers (Tm fiber and blue diode) in one system may achieve high cutting efficiency and optimal coagulation for hemostasis during surgical treatment. Ex vivo testing of the combined system revealed feasibility of this approach. The combination of the CW Tm fiber laser (120W) and the blue diode laser (60W) emitting through a combination tip were compared with CW 120 W Tm fiber laser alone and 120 W Ho:YAG laser. Vaporization rates measured 34, 28, and 6 mm3/s, and coagulation zones measured 0.6, 1.3, and 1.7 mm, respectively. A carbonization zone was only observed with CW Tm fiber laser. The vaporization rate of combined CW Tm fiber laser / blue diode laser was comparable to published data for KTP laser for equivalent total power. Thus, high-power blue diode laser, Tm fiber laser, and

  3. Diode laser spectroscopy of oxygen electronic band at 760 nm

    International Nuclear Information System (INIS)

    Lucchesini, A.; De Rosa, M.; Gozzini, S.

    1998-01-01

    Collisional broadening and shift coefficients have been obtained by analyzing the line shapes of oxygen absorptions in the 760 nm electronic band. By using a diode laser spectrometer with commercially available etherostructure Al x Ga 1-x As diode lasers operating in 'free-running mode', line shape parameters have been collected at room temperature by varying the gas pressure. A systematic study has been carried on seven absorption lines by scanning the diode laser emission wavelength around the gas resonances. The weak absorption lines have been detected by using the wavelength modulation (WM) spectroscopy technique with second-harmonic detection

  4. Printed sub-100 nm polymer-derived ceramic structures.

    Science.gov (United States)

    Duong, Binh; Gangopadhyay, Palash; Brent, Josh; Seraphin, Supapan; Loutfy, Raouf O; Peyghambarian, Nasser; Thomas, Jayan

    2013-05-01

    We proposed an unconventional fabrication technique called spin-on nanoprinting (SNAP) to generate and transfer sub-100 nm preceramic polymer patterns onto flexible and rigid substrates. The dimensions of printed nanostructures are almost the same as those of the mold, since the ceramic precursor used is a liquid. The printed patterns can be used as a replica for printing second-generation structures using other polymeric materials or they can be further converted to desirable ceramic structures, which are very attractive for high-temperature and harsh environment applications. SNAP is an inexpensive parallel process and requires no special equipment for operation.

  5. A 205GHz Amplifier in 90nm CMOS Technology

    Science.gov (United States)

    2017-03-01

    10.5dB power gain, Psat of -1.6dBm, and P1dB ≈ -5.8dBm in a standard 90nm CMOS process. Moreover, the design employs internal (layout-based) /external...other advantages, such as low- cost , reliability, and mixed-mode analog/digital chips, intensifying its usage in the mm-wave band [5]. CMOS has several... disadvantages at the higher frequency range with the worst case scenario happening when the device operates near its fmax. This is chiefly due to

  6. Spectroscopy of Pluto, 380-930 Nm at Six Longitudes

    Science.gov (United States)

    Cruikshank, D. P.; Pinilla-Alonso, N.; Lorenzi, V.; Grundy, William; Licandro, J.; Binzel, R. P.

    2014-01-01

    We have obtained spectra of the Pluto-Charon pair (unresolved) in the wavelength range 380-930 nm with resolution approx..450 at six roughly equally spaced longitudes. The data were taken in May and June, 2014, with the 4.2-m Isaac Newton Telescope at Roque de Los Muchachos Observatory in the Canary Islands, using the ACAM (auxiliary-port camera) in spectrometer mode, and using two solar analog stars. The new spectra clearly show absorption bands of solid CH4 at 620, 728, and 850-910 nm, which were known from earlier work. The 620-nm CH4 band is intrinsically very weak, and its appearance indicates a long optical path-length through the ice. This is especially true if it arises from CH4 dissolved in N2 ice. Earlier work (Owen et al. Science 261, 745, 1993) on the near-infrared spectrum of Pluto (1-2.5 microns) has shown that the CH4 bands are shifted to shorter wavelengths because the CH4 occurs as a solute in beta-phase crystalline N2. The optical path-length through the N2 crystals must be on the order of several cm to produce the N2 band observed at 2.15 microns. The new spectra exhibit a pronounced red slope across the entire wavelength range; the slope is variable with longitude, and differs in a small but significant way from that measured at comparable longitudes by Grundy & Fink (Icarus 124, 329, 1996) in their 15-year study of Pluto's spectrum (500-1000 nm). The new spectra will provide an independent means for calibrating the color filter bands on the Multispectral Visible Imaging Camera (MVIC) (Reuter et al. Space Sci. Rev. 140, 129, 2008) on the New Horizons spacecraft, which will encounter the Pluto-Charon system in mid-2015. They will also form the basis of modeling the spectrum of Pluto at different longitudes to help establish the nature of the non-ice component(s) of Pluto's surface. It is presumed that the non-ice component is the source of the yellow-red coloration of Pluto, which is known to be variable across the surface.

  7. The nanosizing of fluorescent objects by 458 nm spatially modulated illumination microscopy using a simplified size evaluation algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, Andreas; Wagner, Christian; Cremer, Christoph [Kirchhoff-Institute for Physics of the University, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany)

    2004-07-07

    In fluorescent light microscopy, structured illumination approaches have emerged as a novel tool to analyse subwavelength sized objects in thick transparent specimens. In this report, new size measurements ('nanosizing') of small subwavelength sized fluorescent objects applying spatially modulated illumination (SMI) microscopy with an excitation wavelength of {lambda}{sub ex} 458 nm are presented. These measurements were made using fluorescent particles with a given diameter. From the SMI data achieved, the size (diameter) was determined using special calibration curves derived from analytical considerations assuming a Gaussian dye distribution within the object. The results showed that with SMI microscopy combined with suitable calibration, size measurements of objects considerably smaller than the epifluorescent optical resolution at {lambda}{sub ex} = 458 nm are feasible.

  8. Advances in Biomagnetic Interfacing Concepts Derived from Polymer-Magnetic Particle Complexes

    National Research Council Canada - National Science Library

    Riffle, Judy S

    2005-01-01

    Our research on the development and characterization of magnetic nanoparticle-polymer complexes for tile project period 6/1/03-12/31/04 has yielded approximately 10-nm diameter cobalt particles coated...

  9. Hygroscopicity and chemical composition of Antarctic sub-micrometre aerosol particles and observations of new particle formation

    Directory of Open Access Journals (Sweden)

    E. Asmi

    2010-05-01

    Full Text Available The Antarctic near-coastal sub-micrometre aerosol particle features in summer were characterised based on measured data on aerosol hygroscopicity, size distributions, volatility and chemical ion and organic carbon mass concentrations. Hysplit model was used to calculate the history of the air masses to predict the particle origin. Additional measurements of meteorological parameters were utilised. The hygroscopic properties of particles mostly resembled those of marine aerosols. The measurements took place at 130 km from the Southern Ocean, which was the most significant factor affecting the particle properties. This is explained by the lack of additional sources on the continent of Antarctica. The Southern Ocean was thus a likely source of the particles and nucleating and condensing vapours. The particles were very hygroscopic (HGF 1.75 at 90 nm and very volatile. Most of the sub-100 nm particle volume volatilised below 100 °C. Based on chemical data, particle hygroscopic and volatile properties were explained by a large fraction of non-neutralised sulphuric acid together with organic material. The hygroscopic growth factors assessed from chemical data were similar to measured. Hygroscopicity was higher in dry continental air masses compared with the moist marine air masses. This was explained by the aging of the marine organic species and lower methanesulphonic acid volume fraction together with the changes in the inorganic aerosol chemistry as the aerosol had travelled long time over the continental Antarctica. Special focus was directed in detailed examination of the observed new particle formation events. Indications of the preference of negative over positive ions in nucleation could be detected. However, in a detailed case study, the neutral particles dominated the particle formation process. Freshly nucleated particles had the smallest hygroscopic growth factors, which increased subsequent to particle aging.

  10. 240 nm UV LEDs for LISA test mass charge control

    Science.gov (United States)

    Olatunde, Taiwo; Shelley, Ryan; Chilton, Andrew; Serra, Paul; Ciani, Giacomo; Mueller, Guido; Conklin, John

    2015-05-01

    Test Masses inside the LISA Gravitational Reference Sensor must maintain almost pure geodesic motion for gravitational waves to be successfully detected. LISA requires residual test mass accelerations below 3 fm/s2/√Hz at all frequencies between 0.1 and 3 mHz. One of the well-known noise sources is associated with the charges on the test masses which couple to stray electrical potentials and external electromagnetic fields. LISA Pathfinder will use Hg-discharge lamps emitting mostly around 254 nm to discharge the test masses via photoemission in its 2015/16 flight. A future LISA mission launched around 2030 will likely replace the lamps with newer UV-LEDs. Presented here is a preliminary study of the effectiveness of charge control using latest generation UV-LEDs which produce light at 240 nm with energy above the work function of pure Au. Their lower mass, better power efficiency and small size make them an ideal replacement for Hg lamps.

  11. 240 nm UV LEDs for LISA test mass charge control

    International Nuclear Information System (INIS)

    Olatunde, Taiwo; Shelley, Ryan; Chilton, Andrew; Serra, Paul; Ciani, Giacomo; Mueller, Guido; Conklin, John

    2015-01-01

    Test Masses inside the LISA Gravitational Reference Sensor must maintain almost pure geodesic motion for gravitational waves to be successfully detected. LISA requires residual test mass accelerations below 3 fm/s 2 /√Hz at all frequencies between 0.1 and 3 mHz. One of the well-known noise sources is associated with the charges on the test masses which couple to stray electrical potentials and external electromagnetic fields. LISA Pathfinder will use Hg-discharge lamps emitting mostly around 254 nm to discharge the test masses via photoemission in its 2015/16 flight. A future LISA mission launched around 2030 will likely replace the lamps with newer UV-LEDs. Presented here is a preliminary study of the effectiveness of charge control using latest generation UV-LEDs which produce light at 240 nm with energy above the work function of pure Au. Their lower mass, better power efficiency and small size make them an ideal replacement for Hg lamps. (paper)

  12. Stress release during cyclic loading of 20 nm palladium films

    International Nuclear Information System (INIS)

    Lukáč, František; Vlček, Marián; Vlach, Martin; Wagner, Stefan; Uchida, Helmut; Pundt, Astrid; Bell, Anthony; Čížek, Jakub

    2015-01-01

    Highlights: • Repeated hydrogenation of 20 nm Pd films was investigated by in situ X-ray diffraction. • Hydride precipitates form coherent interfaces with matrix in nanocrystalline and epitaxial thin films. • Grain boundaries affect precipitation of the hydride phase in the nanocrystalline film. • Stress in epitaxial film is tensile due to different thermal expansion of Pd and sapphire. • After hydrogen absorption/desorption cycle the stress in both films becomes tensile. - Abstract: Gas phase loading of nanocrystalline and epitaxial 20 nm Pd films deposited on single crystalline sapphire substrates was studied in this work. The nanocrystalline film was deposited at room temperature and the epitaxial film deposited at 800 °C. The nanocrystalline film suffers from in-plane compressive stress imposed by atomic peening processes. The epitaxial film exhibits tensile stress caused by the different thermal expansion coefficients of Pd and sapphire substrate. Coherent phase transition into the hydride phase was observed both for the nanocrystalline and for the epitaxial film. For both films, the lattice parameters continuously increase during the phase transition to the hydride phase. Both films exhibit enhanced hydride formation pressure compared to bulk Pd. Misfit dislocations are formed at interface between Pd film and substrate during hydrogenation. This leads to irreversible change of stress state of the films subjected to sorption and desorption cycle with hydrogen

  13. Quality metric for accurate overlay control in <20nm nodes

    Science.gov (United States)

    Klein, Dana; Amit, Eran; Cohen, Guy; Amir, Nuriel; Har-Zvi, Michael; Huang, Chin-Chou Kevin; Karur-Shanmugam, Ramkumar; Pierson, Bill; Kato, Cindy; Kurita, Hiroyuki

    2013-04-01

    The semiconductor industry is moving toward 20nm nodes and below. As the Overlay (OVL) budget is getting tighter at these advanced nodes, the importance in the accuracy in each nanometer of OVL error is critical. When process owners select OVL targets and methods for their process, they must do it wisely; otherwise the reported OVL could be inaccurate, resulting in yield loss. The same problem can occur when the target sampling map is chosen incorrectly, consisting of asymmetric targets that will cause biased correctable terms and a corrupted wafer. Total measurement uncertainty (TMU) is the main parameter that process owners use when choosing an OVL target per layer. Going towards the 20nm nodes and below, TMU will not be enough for accurate OVL control. KLA-Tencor has introduced a quality score named `Qmerit' for its imaging based OVL (IBO) targets, which is obtained on the-fly for each OVL measurement point in X & Y. This Qmerit score will enable the process owners to select compatible targets which provide accurate OVL values for their process and thereby improve their yield. Together with K-T Analyzer's ability to detect the symmetric targets across the wafer and within the field, the Archer tools will continue to provide an independent, reliable measurement of OVL error into the next advanced nodes, enabling fabs to manufacture devices that meet their tight OVL error budgets.

  14. Biophysical analysis of HTLV-1 particles reveals novel insights into particle morphology and Gag stochiometry

    Directory of Open Access Journals (Sweden)

    Fogarty Keir H

    2010-09-01

    Full Text Available Abstract Background Human T-lymphotropic virus type 1 (HTLV-1 is an important human retrovirus that is a cause of adult T-cell leukemia/lymphoma. While an important human pathogen, the details regarding virus replication cycle, including the nature of HTLV-1 particles, remain largely unknown due to the difficulties in propagating the virus in tissue culture. In this study, we created a codon-optimized HTLV-1 Gag fused to an EYFP reporter as a model system to quantitatively analyze HTLV-1 particles released from producer cells. Results The codon-optimized Gag led to a dramatic and highly robust level of Gag expression as well as virus-like particle (VLP production. The robust level of particle production overcomes previous technical difficulties with authentic particles and allowed for detailed analysis of particle architecture using two novel methodologies. We quantitatively measured the diameter and morphology of HTLV-1 VLPs in their native, hydrated state using cryo-transmission electron microscopy (cryo-TEM. Furthermore, we were able to determine HTLV-1 Gag stoichiometry as well as particle size with the novel biophysical technique of fluorescence fluctuation spectroscopy (FFS. The average HTLV-1 particle diameter determined by cryo-TEM and FFS was 71 ± 20 nm and 75 ± 4 nm, respectively. These values are significantly smaller than previous estimates made of HTLV-1 particles by negative staining TEM. Furthermore, cryo-TEM reveals that the majority of HTLV-1 VLPs lacks an ordered structure of the Gag lattice, suggesting that the HTLV-1 Gag shell is very likely to be organized differently compared to that observed with HIV-1 Gag in immature particles. This conclusion is supported by our observation that the average copy number of HTLV-1 Gag per particle is estimated to be 510 based on FFS, which is significantly lower than that found for HIV-1 immature virions. Conclusions In summary, our studies represent the first quantitative biophysical

  15. Safety and Efficacy of a 1550nm/1927nm Dual Wavelength Laser for the Treatment of Photodamaged Skin.

    Science.gov (United States)

    Narurkar, Vic A; Alster, Tina S; Bernstein, Eric F; Lin, Tina J; Loncaric, Anya

    2018-01-01

    BACKGROUND: Fractional photothermolysis (FP) is a popular treatment option for photodamaged skin and addresses shortcomings of ablative skin resurfacing and nonablative dermal remodeling. Previous studies have demonstrated that FP using the 1550nm wavelength has led to improvement of ultrastructural changes and clinical effects associated with photodamaged skin in the deeper dermal structures, while treatment with the 1927nm wavelength has shown clinical effects in the superficial dermis. Both wavelengths produce precise microscopic treatment zones (MTZs) in the skin. The two wavelengths used in combination may optimize the delivery of fractional nonablative resurfacing intended for dermal and epidermal coagulation of photodamage skin. OBJECTIVES: To evaluate the safety and efficacy of a 1550/1927 Laser System (Fraxel Dual, Solta), using both 1550nm and 1927nm wavelengths in combination for treatment of facial and non-facial photodamage. METHODS: Prospective, multi-center, post-market study in subjects with clinically identifiable photodamage (N=35) (Fitzpatrick skin types I-IV). Both 1550nm and 1927nm wavelengths were used at each treatment visit. Investigator assessment of the affected area(s) occurred at one week, one month and 3 months after a series of up to four treatments. Severity of adverse events (AEs) were assessed using a 4-point scale (where 0=none and 3=marked). Assessments included erythema, edema, hyperkeratosis, hyper- and hypo-pigmentation, scarring, itchiness, dryness, and flaking. Severity of photoaging, fine and coarse wrinkling, mottled hyperpigmentation, sallowness, and tactile roughness at baseline was assessed using the same scale. Investigators and subjects assessed overall appearance of photodamage and pigmentation based on a 5-point quartile improvement scale at all follow-up visits (where 0=no improvement and 4=very significant improvement [76%-100%]). RESULTS: There was a positive treatment effect at all study visits, with moderate

  16. Gold nano-particles fixed on glass

    International Nuclear Information System (INIS)

    Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

    2012-01-01

    Highlights: ► We produced wear resistant gold–ruby coatings on amorphous substrates. ► Thin sputtered gold layers were covered by or embedded in silica coatings. ► Annealing above T g of the substrate glass led to the formation of gold nano particles. ► A 1 1 1-texture of the gold particles is observed via XRD and EBSD. ► EBSD-patterns can be acquired from crystals covered by a thin layer of glass. - Abstract: A simple process for producing wear resistant gold nano-particle coatings on transparent substrates is proposed. Soda-lime-silica glasses were sputtered with gold and subsequently coated with SiO 2 using a combustion chemical vapor deposition technique. Some samples were first coated with silica, sputtered with gold and then coated with a second layer of silica. The samples were annealed for 20 min at either 550 or 600 °C. This resulted in the formation of round, well separated gold nano-particles with sizes from 15 to 200 nm. The color of the coated glass was equivalent to that of gold–ruby glasses. Silica/gold/silica coatings annealed at 600 °C for 20 min were strongly adherent and scratch resistant. X-ray diffraction and electron backscatter diffraction (EBSD) were used to describe the crystal orientations of the embedded particles. The gold particles are preferably oriented with their (1 1 1) planes perpendicular to the surface.

  17. Sodium caseinate stabilized zein colloidal particles.

    Science.gov (United States)

    Patel, Ashok R; Bouwens, Elisabeth C M; Velikov, Krassimir P

    2010-12-08

    The present work deals with the preparation and stabilization of zein colloidal particles using sodium caseinate as electrosteric stabilizer. Colloidal particles with well-defined size range (120-150 nm) and negative surface potential (-29 to -47 mV) were obtained using a simple antisolvent precipitation method. Due to the presence of caseinate, the stabilized colloidal particles showed a shift of isoelectric point (IEP) from 6.0 to around pH 5.0 and thus prevent the aggregation of zein near its native IEP (pH 6.2). The particles also showed good stability to varying ionic strength (15 mM-1.5 M NaCl). Furthermore, stabilized particles retained the property of redispersibility after drying. In vitro protein hydrolysis study confirmed that the presence of caseinate did not alter the digestibility of zein. Such colloidal particles could potentially serve as all-natural delivery systems for bioactive molecules in food, pharmaceutical, and agricultural formulations.

  18. Synthesis of SiC nanoparticles by SHG 532 nm Nd:YAG laser ablation of silicon in ethanol

    Science.gov (United States)

    Khashan, Khawla S.; Ismail, Raid A.; Mahdi, Rana O.

    2018-06-01

    In this work, colloidal spherical nanoparticles NPs of silicon carbide SiC have been synthesized using second harmonic generation 532 nm Nd:YAG laser ablation of silicon target dipped in ethanol solution at various laser fluences (1.5-5) J/cm2. X-Ray diffraction XRD, scanning electron microscopy SEM, transmission electron microscope TEM, Fourier transformed infrared spectroscopy FT-IR, Raman spectroscopy, photoluminescence PL spectroscopy, and UV-Vis absorption were employed to examine the structural, chemical and optical properties of SiC NPs. XRD results showed that all synthesised SiC nanoparticles are crystalline in nature and have hexagonal structure with preferred orientation along (103) plane. Raman investigation showed three characteristic peaks 764,786 and 954 cm-1, which are indexing to transverse optic TO phonon mode and longitudinal optic LO phonon mode of 4H-SiC structure. The optical absorption data showed that the values of optical energy gap of SiC nanoparticles prepared at 1.5 J/cm2 was 3.6 eV and was 3.85 eV for SiC synthesised at 5 J/cm2. SEM investigations confirmed that the nanoparticles synthesised at 5 J/cm2 are agglomerated to form larger particles. TEM measurements showed that SiC particles prepared at 1.5 J/cm2 have spherical shape with average size of 25 nm, while the particles prepared at 5 J/cm2 have an average size of 55 nm.

  19. Modeling airflow and particle transport/deposition in pulmonary airways.

    Science.gov (United States)

    Kleinstreuer, Clement; Zhang, Zhe; Li, Zheng

    2008-11-30

    A review of research papers is presented, pertinent to computer modeling of airflow as well as nano- and micron-size particle deposition in pulmonary airway replicas. The key modeling steps are outlined, including construction of suitable airway geometries, mathematical description of the air-particle transport phenomena and computer simulation of micron and nanoparticle depositions. Specifically, diffusion-dominated nanomaterial deposits on airway surfaces much more uniformly than micron particles of the same material. This may imply different toxicity effects. Due to impaction and secondary flows, micron particles tend to accumulate around the carinal ridges and to form "hot spots", i.e., locally high concentrations which may lead to tumor developments. Inhaled particles in the size range of 20nm< or =dp< or =3microm may readily reach the deeper lung region. Concerning inhaled therapeutic particles, optimal parameters for mechanical drug-aerosol targeting of predetermined lung areas can be computed, given representative pulmonary airways.

  20. Variable solar control using thermotropic core/shell particles

    Energy Technology Data Exchange (ETDEWEB)

    Muehling, Olaf; Seeboth, Arno; Ruhmann, Ralf; Potechius, Elvira; Vetter, Renate [Fraunhofer Institute for Applied Polymer Research (IAP), Department of Chromogenic Polymers, Volmerstr. 7B, 12489 Berlin (Germany); Haeusler, Tobias [Brandenburg University of Technology (BTU Cottbus), Chair of Applied Physics/Thermophysics, Konrad-Zuse-Str. 1, 03046 Cottbus (Germany)

    2009-09-15

    Subject of our recent investigations is the utilization of a reversible thermotropic material for a self-regulating sun protection glazing that controls the solar energy input in order to avoid overheating. Based on the well-established UV curing technology for laminated glass a superior thermotropic material with tunable switching characteristics and of low material costs was developed. The polymer layer contains core/shell particles homogeneously dispersed in a UV-cured resin. The particle core in turn consists of an n-alkane mixture that is responsible for the temperature-induced clear/opaque switching. To obtain particles of well-defined size and with a narrow size distribution, the miniemulsion polymerization technique was used. The visible and solar optical properties (normal-normal, normal-hemispherical, and normal-diffuse transmittance) in the off (clear) and in the on state (opaque) were determined by UV/Vis/NIR spectroscopy. Samples containing particles of high median diameter (>800 nm) primarily scatter in the forward direction. However, with smaller particles (300-600 nm) a higher backscattering (reflection) efficiency was achieved. The largest difference in the normal-hemispherical transmittance could be found with a particle amount of 6% and a median scattering domain diameter of {proportional_to}380 nm. (author)

  1. Investigation of transient dynamics of capillary assisted particle assembly yield

    Energy Technology Data Exchange (ETDEWEB)

    Virganavičius, D. [Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, Kaunas LT-51423 (Lithuania); Laboratory of Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Juodėnas, M. [Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, Kaunas LT-51423 (Lithuania); Tamulevičius, T., E-mail: tomas.tamulevicius@ktu.lt [Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, Kaunas LT-51423 (Lithuania); Department of Physics, Kaunas University of Technology, Studentų St. 50, Kaunas LT-51368 (Lithuania); Schift, H. [Laboratory of Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Tamulevičius, S. [Institute of Materials Science, Kaunas University of Technology, K. Baršausko St. 59, Kaunas LT-51423 (Lithuania); Department of Physics, Kaunas University of Technology, Studentų St. 50, Kaunas LT-51368 (Lithuania)

    2017-06-01

    Highlights: • Regular particles arrays were assembled by capillary force assisted deposition. • Deposition yield dynamics was investigated at different thermal velocity regimes. • Yield transient behavior was approximated with logistic function. • Pattern density influence for switching behavior was assessed. - Abstract: In this paper, the transient behavior of the particle assembly yield dynamics when switching from low yield to high yield deposition at different velocity and thermal regimes is investigated. Capillary force assisted particle assembly (CAPA) using colloidal suspension of green fluorescent 270 nm diameter polystyrene beads was performed on patterned poly (dimethyl siloxane) substrates using a custom-built deposition setup. Two types of patterns with different trapping site densities were used to assess CAPA process dynamics and the influence of pattern density and geometry on the deposition yield transitions. Closely packed 300 nm diameter circular pits ordered in hexagonal arrangement with 300 nm pitch, and 2 × 2 mm{sup 2} square pits with 2 μm spacing were used. 2-D regular structures of the deposited particles were investigated by means of optical fluorescence and scanning electron microscopy. The fluorescence micrographs were analyzed using a custom algorithm enabling to identify particles and calculate efficiency of the deposition performed at different regimes. Relationship between the spatial distribution of particles in transition zone and ambient conditions was evaluated and quantified by approximation of the yield profile with a logistic function.

  2. Computer simulation of the spatial distribution of optical radiation arising from knocked-out excited particles

    International Nuclear Information System (INIS)

    Gokov, S.P.; Gritsyna, V.V.; Koval', A.G.; Kovtunenko, Yu.I.; Shevchenko, D.I.

    2004-01-01

    The new approach for the explanation of the spatial distribution of the optical radiation arising from knocked-out excited particles is given. Calculated and experimental data for Al (λ=396.1 nm) and Mg (λ=383.8 nm) knocked-out by Ar + (20 keV) beam from MgAl 2 O 4 surface are compared [ru

  3. Accelerators of atomic particles

    International Nuclear Information System (INIS)

    Sarancev, V.

    1975-01-01

    A brief survey is presented of accelerators and methods of accelerating elementary particles. The principle of collective accelerating of elementary particles is clarified and the problems are discussed of its realization. (B.S.)

  4. Elementary particles and cosmology

    International Nuclear Information System (INIS)

    Audouze, J.; Paty, M.

    2000-01-01

    The universe is the most efficient laboratory of particle physics and the understanding of cosmological processes implies the knowledge of how elementary particles interact. This article recalls the mutual influences between on the one hand: astrophysics and cosmology and on the other hand: nuclear physics and particle physics. The big-bang theory relies on nuclear physics to explain the successive stages of nucleo-synthesis and the study of solar neutrinos has led to discover new aspects of this particle: it is likely that neutrinos undergo oscillations from one neutrino type to another. In some universe events such as the bursting of a super-nova, particles are released with a kinetic energy that would be impossible to reach on earth with a particle accelerator. These events are become common points of interest between astrophysicists and particle physicists and have promoted a deeper cooperation between astrophysics and elementary particle physics. (A.C.)

  5. Particle Physics Education Sites

    Science.gov (United States)

    back to home page Particle Physics Education Sites quick reference Education and Information - National Laboratory Education Programs - Women and Minorities in Physics - Other Physics Sites - Physics Alliance - Accelerators at National Laboratories icon Particle Physics Education and Information sites: top

  6. Formation of microscopic particles during the degradation of different polymers.

    Science.gov (United States)

    Lambert, Scott; Wagner, Martin

    2016-10-01

    This study investigated the formation and size distribution of microscopic plastic particles during the degradation of different plastic materials. Particle number concentrations in the size range 30 nm-60 μm were measured by nanoparticle tracking analysis (NTA) and Coulter Counter techniques. Each of the plastics used exhibited a measureable increase in the release of particles into the surrounding solution, with polystyrene (PS) and polylactic acid (PLA) generating the highest particle concentrations. After 112 d, particle concentrations ranged from 2147 particles ml(-1) in the control (C) to 92,465 particles ml(-1) for PS in the 2-60 μm size class; 1.2 × 10(5) particles ml(-1) (C) to 11.6 × 10(6) for PLA in the 0.6-18 μm size class; and 0.2 × 10(8) particles ml(-1) (C) to 6.4 × 10(8) particles ml(-1) for PS in the 30-2000 nm size class (84 d). A classification of samples based on principal component analysis showed a separation between the different plastic types, with PLA clustering individually in each of the three size classes. In addition, particle size distribution models were used to examine more closely the size distribution data generated by NTA. Overall, the results indicate that at the beginning of plastic weathering processes chain scission at the polymer surface causes many very small particles to be released into the surrounding solution and those concentrations may vary between plastic types. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Deposition and characterization of ITO films produced by laser ablation at 355 nm

    DEFF Research Database (Denmark)

    Holmelund, E.; Thestrup Nielsen, Birgitte; Schou, Jørgen

    2002-01-01

    Indium tin oxide (ITO) films have been deposited by pulsed laser deposition (PLD) at 355 nm. Even though the absorption of laser light at the wavelength 355 nm is much smaller than that of the standard excimer lasers for PLD at 248 nm and 193 nm, high-quality films can be produced. At high fluence...

  8. Review of particle properties

    Energy Technology Data Exchange (ETDEWEB)

    Yost, G P; Barnett, R M; Hinchliffe, I; Lynch, G R; Rittenberg, A; Ross, R R; Suzuki, M; Trippe, T G; Wohl, C G; Armstrong, B

    1988-04-14

    This review of the properties of gauge bosons, leptons, mesons, and baryons is an updating of the Review of Particle Properties, Particle Data Group (Phys. Lett. 170B (1986)). Data are evaluated, listed, averaged, and summarized in tables. We continue the more orderly set of particle names implemented in the 1986 edition. Numerous tables, figures, and formulae of interest to particle physicists are also included. A data booklet is available.

  9. Beyond the God particle

    CERN Document Server

    Lederman, Leon M

    2013-01-01

    On July 4, 2012, the long-sought Higgs Boson--aka "the God Particle"--was discovered at the world's largest particle accelerator, the LHC, in Geneva, Switzerland. On March 14, 2013, physicists at CERN confirmed it. This elusive subatomic particle forms a field that permeates the entire universe, creating the masses of the elementary particles that are the basic building blocks of everything in the known world--from viruses to elephants, from atoms to quasars.

  10. Exhaust particles of modern gasoline vehicles: A laboratory and an on-road study

    Science.gov (United States)

    Karjalainen, Panu; Pirjola, Liisa; Heikkilä, Juha; Lähde, Tero; Tzamkiozis, Theodoros; Ntziachristos, Leonidas; Keskinen, Jorma; Rönkkö, Topi

    2014-11-01

    Vehicle technology development and upcoming particle emission limits have increased the need for detailed analyses of particle emissions of vehicles using gasoline direct injection (GDI) techniques. In this paper the particle emission characteristics of modern GDI passenger cars were studied in a laboratory and on the road, with the focus on exhaust particle number emissions, size distributions, volatility and morphology. Both during acceleration and steady conditions the number size distribution of nonvolatile exhaust particles consisted of two modes, one with mean particle size below 30 nm and the other with mean particle size approximately 70 nm. Results indicate that both of these particles modes consisted of soot but with different morphologies. Both in laboratory and on the road, significant emissions of exhaust particles were observed also during decelerations conducted by engine braking. These particles are most likely originating from lubricant oil ash components. The semivolatile nucleation particles were observed in the laboratory experiments at high engine load conditions. Thus, in general, the study indicates that a modern gasoline vehicle can emit four distinctive types of exhaust particles. The differences in particle characteristics and formation should be taken into account in the development of emission control strategies and technologies and, on the other hand, in the assessment of the impact of particle emissions on environment and human health.

  11. Contribution of ship traffic to aerosol particle concentrations downwind of a major shipping lane

    DEFF Research Database (Denmark)

    Kivekäs, N.; Massling, Andreas; Grythe, H.

    2014-01-01

    at a remote location. We studied the particle number concentration (12 to 490 nm in diameter), the mass concentration (12 to 150 nm in diameter) and number and volume size distribution of aerosol particles in ship plumes for a period of 4.5 months at Hovsore, a coastal site on the western coast of Jutland...... in Denmark. During episodes of western winds, the site is about 50 km downwind of a major shipping lane and the plumes are approximately 1 hour old when they arrive at the site. We have used a sliding percentile-based method for separating the plumes from the measured background values and to calculate...... the ship plume contribution to the total particle number and PM0.15 mass concentration (mass of particles below 150 nm in diameter, converted from volume assuming sphericity) at the site. The method is not limited to particle number or volume concentration, but can also be used for different chemical...

  12. Particle physics and cosmology

    International Nuclear Information System (INIS)

    Schramm, D.N.; Turner, M.S.

    1982-06-01

    work is described in these areas: cosmological baryon production; cosmological production of free quarks and other exotic particle species; the quark-hadron transition in the early universe; astrophysical and cosmological constraints on particle properties; massive neutrinos; phase transitions in the early universe; and astrophysical implications of an axion-like particle

  13. Particle-nuclear intersections

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    With the traditional distinctions between particle and nuclear physics becoming increasing blurred, the Fifth Conference on the Intersections of Particle and Nuclear Physics, held from May 31 to June 6 in St. Petersburg, Florida, brought together particle and nuclear physicists to discuss common research efforts and to define and plan a united approach

  14. Review of particle properties

    International Nuclear Information System (INIS)

    Trippe, T.G.; Barbaro-Galtieri, A.; Kelly, R.L.; Rittenberg, A.; Rosenfeld, A.H.; Yost, G.P.; Barash-Schmidt, N.; Bricman, C.; Hemingway, R.J.; Losty, M.J.; Roos, M.; Chaloupka, V.; Armstrong, B.

    1976-01-01

    This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Phys. Letters 50B, No.1 (1974), and Supplement, Rev. Mod. Phys. 47 (1975) 535]. Data are evaluated, listed, averaged, and summarized in tables. Numerous tables, figures, and formulae of interest to particle physicists are also included. A data booklet is available

  15. Atomic Particle Detection

    Energy Technology Data Exchange (ETDEWEB)

    Hellman, Hal

    1970-01-01

    This booklet tells how scientists observe the particles and electromagnetic radiation that emerges from an atomic nucleus. The equipment used falls into two general categories: counters which count each particle as it passes by, and track detectors, which make a photographic record of the particle's track.

  16. Pollution Prevention Opportunity Assessment for the SNL/NM cafeterias.

    Energy Technology Data Exchange (ETDEWEB)

    McCord, Samuel Adam

    2005-12-01

    This Pollution Prevention Opportunity Assessment (PPOA) was conducted for the two Sandia National Laboratories/New Mexico cafeteria facilities between May and August 2005. The primary purpose of this PPOA is to assess waste and resource reduction opportunities and issue Pollution Prevention (P2) recommendations for Sandia's food service facilities. This PPOA contains recommendations for energy, water and resource reduction, as well as material substitution based upon environmentally preferable purchasing. Division 3000 has requested the PPOA report as part of the Division's compliance effort to implement the Environmental Management System (EMS) per DOE Order 450.1. This report contains a summary of the information collected and analyses performed with recommended options for implementation. The SNL/NM P2 Group will work with Division 3000 and the respective cafeteria facilities to implement these options.

  17. Extreme ultraviolet resist materials for sub-7 nm patterning

    KAUST Repository

    Li, Li; Liu, Xuan; Pal, Shyam; Wang, Shulan; Ober, Christopher K.; Giannelis, Emmanuel P.

    2017-01-01

    Continuous ongoing development of dense integrated circuits requires significant advancements in nanoscale patterning technology. As a key process in semiconductor high volume manufacturing (HVM), high resolution lithography is crucial in keeping with Moore's law. Currently, lithography technology for the sub-7 nm node and beyond has been actively investigated approaching atomic level patterning. EUV technology is now considered to be a potential alternative to HVM for replacing in some cases ArF immersion technology combined with multi-patterning. Development of innovative resist materials will be required to improve advanced fabrication strategies. In this article, advancements in novel resist materials are reviewed to identify design criteria for establishment of a next generation resist platform. Development strategies and the challenges in next generation resist materials are summarized and discussed.

  18. EST Table: NM_001111334 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available NM_001111334 Br-c 10/09/29 81 %/420 aa ref|NP_001104804.1| broad-complex isoform Z1... [Bombyx mori] dbj|BAD23978.1| broad-complex Z1-isoform [Bombyx mori] dbj|BAD23983.1| broad-complex Z1-isofo...rm [Bombyx mori] dbj|BAD24045.1| Broad-Complex isoform Z1 [Bombyx mori] dbj|BAD24046.1| Broad-Complex isofor...m Z1 [Bombyx mori] dbj|BAD46732.1| broad-complex A-Z1 isoform [Bombyx mori] dbj|BAD46739.1| broad...-complex B-Z1 isoform [Bombyx mori] dbj|BAF43564.1| Broad-Complex isoform Z1 [Bombyx mori] 1

  19. Database of average-power damage thresholds at 1064 nm

    International Nuclear Information System (INIS)

    Rainer, F.; Hildum, E.A.; Milam, D.

    1987-01-01

    We have completed a database of average-power, laser-induced, damage thresholds at 1064 nm on a variety of materials. Measurements were made with a newly constructed laser to provide design input for moderate and high average-power laser projects. The measurements were conducted with 16-ns pulses at pulse-repetition frequencies ranging from 6 to 120 Hz. Samples were typically irradiated for time ranging from a fraction of a second up to 5 minutes (36,000 shots). We tested seven categories of samples which included antireflective coatings, high reflectors, polarizers, single and multiple layers of the same material, bare and overcoated metal surfaces, bare polished surfaces, and bulk materials. The measured damage threshold ranged from 2 for some metals to > 46 J/cm 2 for a bare polished glass substrate. 4 refs., 7 figs., 1 tab

  20. Photooxidation of polystyrene: irradiation at 254 and 365 nm

    International Nuclear Information System (INIS)

    Otocka, E.P.; Curran, S.; Porter, R.S.

    1983-01-01

    Studies have been made of the near surface photooxidation of atactic polystyrene films prepared in the absence of air. The samples were photooxidized on exposure to air at two frequencies, 254 and 365 nm, using a calibrated mercury irradiation source with filters. Most studies were made at 40 0 C and as a function of irradiation time with the reactions characterized by changes in molecular weight and composition. The former was evaluated by gel permeation chromatography and the latter by transmission Fourier transform infrared ir spectroscopy and by multiple-internal-reflectance ir spectra using different angles and different crystals to evaluate compositions as a function of film depth. Species identified in photooxidation include the generation of hydroperoxides and the appearance of carbonyl bands with the latter identified by the spectral shift associated with the exposure of the photooxidized polystyrene surface to ammonia. These results suggest that principal products of near-surface oxidation of polystyrene are carboxylic acids. 6 figures, 1 table

  1. Pixel front-end development in 65 nm CMOS technology

    International Nuclear Information System (INIS)

    Havránek, M; Hemperek, T; Kishishita, T; Krüger, H; Wermes, N

    2014-01-01

    Luminosity upgrade of the LHC (HL-LHC) imposes severe constraints on the detector tracking systems in terms of radiation hardness and capability to cope with higher hit rates. One possible way of keeping track with increasing luminosity is the usage of more advanced technologies. Ultra deep sub-micron CMOS technologies allow a design of complex and high speed electronics with high integration density. In addition, these technologies are inherently radiation hard. We present a prototype of analog pixel front-end integrated circuit designed in 65 nm CMOS technology with applications oriented towards the ATLAS Pixel Detector upgrade. The aspects of ultra deep sub-micron design and performance of the analog pixel front-end circuits will be discussed

  2. Extreme ultraviolet resist materials for sub-7 nm patterning.

    Science.gov (United States)

    Li, Li; Liu, Xuan; Pal, Shyam; Wang, Shulan; Ober, Christopher K; Giannelis, Emmanuel P

    2017-08-14

    Continuous ongoing development of dense integrated circuits requires significant advancements in nanoscale patterning technology. As a key process in semiconductor high volume manufacturing (HVM), high resolution lithography is crucial in keeping with Moore's law. Currently, lithography technology for the sub-7 nm node and beyond has been actively investigated approaching atomic level patterning. EUV technology is now considered to be a potential alternative to HVM for replacing in some cases ArF immersion technology combined with multi-patterning. Development of innovative resist materials will be required to improve advanced fabrication strategies. In this article, advancements in novel resist materials are reviewed to identify design criteria for establishment of a next generation resist platform. Development strategies and the challenges in next generation resist materials are summarized and discussed.

  3. Wide modulation bandwidth terahertz detection in 130 nm CMOS technology

    Science.gov (United States)

    Nahar, Shamsun; Shafee, Marwah; Blin, Stéphane; Pénarier, Annick; Nouvel, Philippe; Coquillat, Dominique; Safwa, Amr M. E.; Knap, Wojciech; Hella, Mona M.

    2016-11-01

    Design, manufacturing and measurements results for silicon plasma wave transistors based wireless communication wideband receivers operating at 300 GHz carrier frequency are presented. We show the possibility of Si-CMOS based integrated circuits, in which by: (i) specific physics based plasma wave transistor design allowing impedance matching to the antenna and the amplifier, (ii) engineering the shape of the patch antenna through a stacked resonator approach and (iii) applying bandwidth enhancement strategies to the design of integrated broadband amplifier, we achieve an integrated circuit of the 300 GHz carrier frequency receiver for wireless wideband operation up to/over 10 GHz. This is, to the best of our knowledge, the first demonstration of low cost 130 nm Si-CMOS technology, plasma wave transistors based fast/wideband integrated receiver operating at 300 GHz atmospheric window. These results pave the way towards future large scale (cost effective) silicon technology based terahertz wireless communication receivers.

  4. Extreme ultraviolet resist materials for sub-7 nm patterning

    KAUST Repository

    Li, Li

    2017-06-26

    Continuous ongoing development of dense integrated circuits requires significant advancements in nanoscale patterning technology. As a key process in semiconductor high volume manufacturing (HVM), high resolution lithography is crucial in keeping with Moore\\'s law. Currently, lithography technology for the sub-7 nm node and beyond has been actively investigated approaching atomic level patterning. EUV technology is now considered to be a potential alternative to HVM for replacing in some cases ArF immersion technology combined with multi-patterning. Development of innovative resist materials will be required to improve advanced fabrication strategies. In this article, advancements in novel resist materials are reviewed to identify design criteria for establishment of a next generation resist platform. Development strategies and the challenges in next generation resist materials are summarized and discussed.

  5. TMV Disk Scaffolds for Making sub-30 nm Silver Nanorings.

    Science.gov (United States)

    Bayram, Serene; Zahr, Omar; Del Re, Julia; Blum, Amy Szuchmacher

    2018-01-01

    Nanosized bioscaffolds can be utilized to tackle the challenge of size reduction of metallic rings owing to their miniature features as well as their well-known biomineralization capacity. The tobacco mosaic virus coat protein is used as a command surface to grow and assemble silver nanoparticles into sub-30 nm rings. The versatility of TMV allows the formation of both solid silver rings and rings consisting of discrete silver nanoparticles. The pH-dependent coulombic surface map along with the annular geometry of the protein aggregate allow the generation of rings with or without a central nanoparticle. Our silver rings are believed to be the smallest to date, and they can offer a test material for existing theories on metallic nanorings of this heretofore unreached size scale.

  6. Sub-10 nm patterning with DNA nanostructures: a short perspective

    Science.gov (United States)

    Du, Ke; Park, Myeongkee; Ding, Junjun; Hu, Huan; Zhang, Zheng

    2017-11-01

    DNA is the hereditary material that contains our unique genetic code. Since the first demonstration of two-dimensional (2D) nanopatterns by using designed DNA origami ˜10 years ago, DNA has evolved into a novel technique for 2D and 3D nanopatterning. It is now being used as a template for the creation of sub-10 nm structures via either ‘top-down’ or ‘bottom-up’ approaches for various applications spanning from nanoelectronics, plasmonic sensing, and nanophotonics. This perspective starts with an histroric overview and discusses the current state-of-the-art in DNA nanolithography. Emphasis is put on the challenges and prospects of DNA nanolithography as the next generation nanomanufacturing technique.

  7. Technology of focus detection for 193nm projection lithographic tool

    Science.gov (United States)

    Di, Chengliang; Yan, Wei; Hu, Song; Xu, Feng; Li, Jinglong

    2012-10-01

    With the shortening printing wavelength and increasing numerical aperture of lithographic tool, the depth of focus(DOF) sees a rapidly drop down trend, reach a scale of several hundred nanometers while the repeatable accuracy of focusing and leveling must be one-tenth of DOF, approximately several dozen nanometers. For this feature, this article first introduces several focusing technology, Obtained the advantages and disadvantages of various methods by comparing. Then get the accuracy of dual-grating focusing method through theoretical calculation. And the dual-grating focusing method based on photoelastic modulation is divided into coarse focusing and precise focusing method to analyze, establishing image processing model of coarse focusing and photoelastic modulation model of accurate focusing. Finally, focusing algorithm is simulated with MATLAB. In conclusion dual-grating focusing method shows high precision, high efficiency and non-contact measurement of the focal plane, meeting the demands of focusing in 193nm projection lithography.

  8. Spectral narrowing of a 980 nm tapered diode laser bar

    DEFF Research Database (Denmark)

    Vijayakumar, Deepak; Jensen, Ole Bjarlin; Lucas Leclin, Gaëlle

    2011-01-01

    High power diode laser bars are interesting in many applications such as solid state laser pumping, material processing, laser trapping, laser cooling and second harmonic generation. Often, the free running laser bars emit a broad spectrum of the order of several nanometres which limit their scope...... been "smile corrected" using individual phase masks for each emitter. The external cavity consists of the laser bar, both fast and slow axis micro collimators, smile correcting phase mask, 6.5x beam expanding lens combination, a 1200 lines/mm reflecting grating with 85% efficiency in the first order......, a slow axis focusing cylindrical lens of 40 mm focal length and an output coupler which is 10% reflective. In the free running mode, the laser emission spectrum was 5.5 nm wide at an operating current of 30A. The output power was measured to be in excess of 12W. Under the external cavity operation...

  9. Lasing at 300 nm and below: Optical challenges and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Garzella, D. [Universite de Paris-Sud, Orsay (France); Couprie, M.E. [Universite de Paris-Sud, Orsay (France)]|[CEA DSM DRECAM SPAM, Gif Sur Yvette (France); Billardon, M. [ESPCI, Paris (France)

    1995-12-31

    The FEL experiment in the visible and near UV on the Super ACO storage ring has given, since 1989, important informations on the SRFEL dynamics and, furthermore, a very good beam stability has been achieved. In addition, the operation at 350 nm with this good stability and a long beam lifetime allowed us to perform the first user experiment in biology and to start with a campaign for using the laser as photons source for experiments in other domains, coupling FEL light and the Synchrotron Radiation. For this, FEL starts to be very competitive with respect to the other conventional laser sources, provided that it could oscillate further in the UV, say at 300 nm and below. So, the real challenge is now given by the lasing at shorter wavelengths and, for this, by the optical technology existing nowadays. Since 1992 the efforts have been concentrating to look for every kind of solution allowing us to overcome the problem of having a very low gain. From an optical point of view, in the range of wavelengths explored, there is a lack of transparents dielectric materials for substrates and coatings. Substrates are required at the same time to be relatively not absorbing (a few tens 10{sup -6}), to have a very good surface quality (RMS roughness below 10 {Angstrom}) because of scattering losses dramatically increasing in this spectral range and, due to the thermal load of the undulator emission, to have adequate thermal characteristics. In order to fulfill all these requirements, a good characterisation and modelisation of the substrates is needed, especially to correlate thermal loading and mechanical deformations from one hand, and roughness and scattering losses from the other hand. Coatings must be not absorbing too and, above all, the most amorphous as possible (this could be obtained with IBS deposition technique), in order to insure a good reproduction of the substrate roughness at the interfaces and on the top layer and an higher resistance to the XUV photons load.

  10. Time-resolved photodissociation of oxygen at 162 nm

    International Nuclear Information System (INIS)

    Trushin, Sergei A; Schmid, Wolfram E; Fuss, Werner

    2011-01-01

    Oxygen was excited by 10 fs pulses in the Schumann-Runge continuum at 162 nm, which is by 0.57 eV above the dissociation limit. It was probed by high-intensity ionization at 810 nm with 10 14 W cm -2 , measuring the ion yields. The O 2 + signal decays in 4.3 fs, which is much shorter than the expected time for dissociation. It is ascribed to a rapid decay of the ionization probability. In a similar time, the ion in the second excited state (with excess energy taken over from the neutral) reaches the dissociation limit, whereas this time would be much longer from the two lower ion states. In fact, the O + signal rises to a (first) maximum at 6 fs. The preference for the higher ion state is rationalized by an intermediate resonance in the neutral molecule for which the polarization dependence also provides evidence. But the shape of the O + signal is very odd: it exhibits three maxima (at 6, 29 and 53 fs) of increasing intensity, before decaying rapidly (≤3.5 fs) to a pedestal. In contrast to the first maximum, the others appear at times when there is practically no interatomic force left in the excited state. We postulate a highly repulsive doubly excited state as a resonance for interpreting the second maximum, and for the third an ion-pair state lying further outside. Comparison is made with enhanced ionization, which has often been found at large interatomic distances on multiple ionization in strong laser fields. Consistent with this mechanism is the absence of similar observations at negative delay times, where five fundamental photons act as a pump and the fifth harmonic as a probe.

  11. Single-particle characterization of ice-nucleating particles and ice particles residuals sampled by three different techniques

    Science.gov (United States)

    Kandler, Konrad; Worringen, Annette; Benker, Nathalie; Dirsch, Thomas; Mertes, Stephan; Schenk, Ludwig; Kästner, Udo; Frank, Fabian; Nillius, Björn; Bundke, Ulrich; Rose, Diana; Curtius, Joachim; Kupiszewski, Piotr; Weingartner, Ernest; Vochezer, Paul; Schneider, Johannes; Schmidt, Susan; Weinbruch, Stephan; Ebert, Martin

    2015-04-01

    During January/February 2013, at the High Alpine Research Station Jungfraujoch a measurement campaign was carried out, which was centered on atmospheric ice-nucleating particles (INP) and ice particle residuals (IPR). Three different techniques for separation of INP and IPR from the non-ice-active particles are compared. The Ice Selective Inlet (ISI) and the Ice Counterflow Virtual Impactor (Ice-CVI) sample ice particles from mixed phase clouds and allow for the analysis of the residuals. The combination of the Fast Ice Nucleus Chamber (FINCH) and the Ice Nuclei Pumped Counterflow Virtual Impactor (IN-PCVI) provides ice-activating conditions to aerosol particles and extracts the activated INP for analysis. Collected particles were analyzed by scanning electron microscopy and energy-dispersive X-ray microanalysis to determine size, chemical composition and mixing state. All INP/IPR-separating techniques had considerable abundances (median 20 - 70 %) of instrumental contamination artifacts (ISI: Si-O spheres, probably calibration aerosol; Ice-CVI: Al-O particles; FINCH+IN-PCVI: steel particles). Also, potential sampling artifacts (e.g., pure soluble material) occurred with a median abundance of separated by all three techniques. Soot was a minor contributor. Lead was detected in less than 10 % of the particles, of which the majority were internal mixtures with other particle types. Sea-salt and sulfates were identified by all three methods as INP/IPR. Most samples showed a maximum of the INP/IPR size distribution at 400 nm geometric diameter. In a few cases, a second super-micron maximum was identified. Soot/carbonaceous material and metal oxides were present mainly in the submicron range. ISI and FINCH yielded silicates and Ca-rich particles mainly with diameters above 1 µm, while the Ice-CVI also separated many submicron IPR. As strictly parallel sampling could not be performed, a part of the discrepancies between the different techniques may result from

  12. Study of particle swarm optimization particle trajectories

    CSIR Research Space (South Africa)

    Van den Bergh, F

    2006-01-01

    Full Text Available . These theoretical studies concentrate mainly on simplified PSO systems. This paper overviews current theoretical studies, and extend these studies to investigate particle trajectories for general swarms to include the influence of the inertia term. The paper also...

  13. Light scattering by cosmic particles

    NARCIS (Netherlands)

    Hovenier, J.W.; Min, M.

    2008-01-01

    We define cosmic particles as particles outside the Earth. Two types of cosmic particles can be distinguished, namely liquid and solid particles. The solid particles are often called grains or cosmic dust particles. Cosmic particles occur in a great variety of astronomical objects and environments.

  14. Effects of silver nanoparticles (NM-300K) on Lumbricus rubellus earthworms and particle characterization in relevant test matrices including soil

    NARCIS (Netherlands)

    Ploeg, M.J.C. van der; Handy, R.D.; Waalewijn-Kool, P.L.; Berg, J.H.J. van den; Herrera Rivera, Z.E.; Bovenschen, J.; Molleman, B.; Baveco, J.M.; Tromp, P.; Peters, R.J.B.; Koopmans, G.F.; Rietjens, I.M.C.M.; Brink, N.W. van den

    2014-01-01

    The impact of silver nanoparticles (AgNP; at 0mg Ag/kg, 1.5mg Ag/kg, 15.4mg Ag/kg, and 154mg Ag/kg soil) and silver nitrate (AgNO3; 15.4mg Ag/kg soil) on earthworms, Lumbricus rubellus, was assessed. A 4-wk exposure to the highest AgNP treatment reduced growth and reproduction compared with the

  15. Slowing of charged particles by particle methods

    International Nuclear Information System (INIS)

    Mercier, B.

    1985-03-01

    We review some facts about particle methods for solving linear hyperbolic equations. We show how one gets an evaluation of integral quantities like: ∫ u(x,t) zeta(x,t) dxdt where u denotes the solution and zeta an arbitrary weight function. Then, we apply the method to the equation describing charged particle transport in a plasma with emphasis on the evaluation of energy deposition on ions and electrons [fr

  16. Performance evaluation of a fully depleted monolithic pixel detector chip in 150 nm CMOS technology

    Energy Technology Data Exchange (ETDEWEB)

    Obermann, Theresa

    2017-06-15

    The depleted monolithic active pixel sensor (DMAPS) is a new concept integrating full CMOS circuitry onto a (fully) depletable silicon substrate wafer. The realization of prototypes of the DMAPS concept relies on the availability of multiple well CMOS processes and highly resistive substrates. The CMOS foundry ESPROS Photonics offers both and was chosen for prototyping. Two prototypes, EPCB01 and EPCB02, developed in a 150 nm process on a highly resistive n-type wafer of 50 μm thickness, were characterized. The prototypes have 352 square pixels of 40 μm pitch and a small n-well charge collection node with very low capacitance of 5 fF (n{sup +}-implantation size: 5 μm x 5 μm) and about 150 transistors per pixel (CSA and discriminator plus a small digital part). The characterization of the prototypes demonstrates the proof of principle of the concept. Prior to irradiation the prototypes show a signal from a minimum ionizing particle ranging from 2400 e{sup -} to 3000 e{sup -} while the noise is 30 e{sup -} due to the low capacitance. After the irradiation of the prototypes with neutrons up to a fluence of 5 x 10{sup 14} neutrons/cm{sup 2} the performance suffers from the radiation damage leading to a signal of 1000 e{sup -} and a higher noise of 60 e{sup -} due to the increase of the leakage current. The detection efficiency of the prototypes reduces from 94 % to 26 % after the fluence of 5 x 10{sup 14} particles/cm{sup 2}. Due to the small fill factor the detection efficiency shows are strong dependence on the position within the pixel after irradiation. Thus the DMAPS concept with low fill factor can be used for precise vertex reconstruction in High Energy Physics experiments without severe performance loss up to moderate fluences (< 1 x 10{sup 14} particles/cm{sup 2}). The expected particle fluences inside of the volume of the upgrade of the ATLAS pixel detector exceed this limit. However, possible applications could be at future linear collider (ILC or CLIC

  17. Performance evaluation of a fully depleted monolithic pixel detector chip in 150 nm CMOS technology

    International Nuclear Information System (INIS)

    Obermann, Theresa

    2017-06-01

    The depleted monolithic active pixel sensor (DMAPS) is a new concept integrating full CMOS circuitry onto a (fully) depletable silicon substrate wafer. The realization of prototypes of the DMAPS concept relies on the availability of multiple well CMOS processes and highly resistive substrates. The CMOS foundry ESPROS Photonics offers both and was chosen for prototyping. Two prototypes, EPCB01 and EPCB02, developed in a 150 nm process on a highly resistive n-type wafer of 50 μm thickness, were characterized. The prototypes have 352 square pixels of 40 μm pitch and a small n-well charge collection node with very low capacitance of 5 fF (n + -implantation size: 5 μm x 5 μm) and about 150 transistors per pixel (CSA and discriminator plus a small digital part). The characterization of the prototypes demonstrates the proof of principle of the concept. Prior to irradiation the prototypes show a signal from a minimum ionizing particle ranging from 2400 e - to 3000 e - while the noise is 30 e - due to the low capacitance. After the irradiation of the prototypes with neutrons up to a fluence of 5 x 10 14 neutrons/cm 2 the performance suffers from the radiation damage leading to a signal of 1000 e - and a higher noise of 60 e - due to the increase of the leakage current. The detection efficiency of the prototypes reduces from 94 % to 26 % after the fluence of 5 x 10 14 particles/cm 2 . Due to the small fill factor the detection efficiency shows are strong dependence on the position within the pixel after irradiation. Thus the DMAPS concept with low fill factor can be used for precise vertex reconstruction in High Energy Physics experiments without severe performance loss up to moderate fluences (< 1 x 10 14 particles/cm 2 ). The expected particle fluences inside of the volume of the upgrade of the ATLAS pixel detector exceed this limit. However, possible applications could be at future linear collider (ILC or CLIC) experiments and B-factories where the low material budget

  18. Elementary particles. 2

    International Nuclear Information System (INIS)

    Ranft, G.; Ranft, J.

    1977-01-01

    In this part the subject is covered under the following headings, methods for producing high-energy particles; interaction of high-energy particles with matter; methods for the detection of high-energy particles; symmetry properties and conservation laws; quantum number and selection rules; theorem of scattering behaviour at asymptotically high energies; statistical methods in elementary particle physics; interaction of high-energy particles with nuclei; relations of high-energy physics to other branches of science and its response to engineering. Intended as information on high-energy physics for graduate students and research workers familiar with the fundamentals of classical and quantum physics

  19. Review of particle properties

    International Nuclear Information System (INIS)

    Montanet, L.; Gieselmann, K. Technical Associate; Barnett, R.M.; Groom, D.E.; Trippe, T.G.; Wohl, C.G.; Armstrong, B. Technical Associate; Wagman, G.S. Technical Associate; Murayama, H.; Stone, J.; Hernandez, J.J.; Porter, F.C.; Morrison, R.J.; Manohar, A.; Aguilar-Benitez, M.; Caso, C.; Lantero, P. Technical Associate; Crawford, R.L.; Roos, M.; Toernqvist, N.A.; Hayes, K.G.; Hoehler, G.

    1994-01-01

    This biennial review summarizes much of Particle Physics. Using data from previous editions, plus 2300 new measurements from 700 papers, we list evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, monopoles, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review

  20. Fractal-like dimension of nanometer Diesel soot particles

    Energy Technology Data Exchange (ETDEWEB)

    Skillas, G.; Baltensperger, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Siegmann, K. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-11-01

    Measurements with a low-pressure impactor and a differential mobility analyser were conducted for Diesel soot at various engine loads. By means of these measurements a fractal-like dimension of Diesel soot particles, with diameters ranging from 55 up to 260 nm, was established. (author) 2 figs., 7 refs.

  1. Fluidization of spherocylindrical particles

    Science.gov (United States)

    Mahajan, Vinay V.; Nijssen, Tim M. J.; Fitzgerald, Barry W.; Hofman, Jeroen; Kuipers, Hans; Padding, Johan T.

    2017-06-01

    Multiphase (gas-solid) flows are encountered in numerous industrial applications such as pharmaceutical, food, agricultural processing and energy generation. A coupled computational fluid dynamics (CFD) and discrete element method (DEM) approach is a popular way to study such flows at a particle scale. However, most of these studies deal with spherical particles while in reality, the particles are rarely spherical. The particle shape can have significant effect on hydrodynamics in a fluidized bed. Moreover, most studies in literature use inaccurate drag laws because accurate laws are not readily available. The drag force acting on a non-spherical particle can vary considerably with particle shape, orientation with the flow, Reynolds number and packing fraction. In this work, the CFD-DEM approach is extended to model a laboratory scale fluidized bed of spherocylinder (rod-like) particles. These rod-like particles can be classified as Geldart D particles and have an aspect ratio of 4. Experiments are performed to study the particle flow behavior in a quasi-2D fluidized bed. Numerically obtained results for pressure drop and bed height are compared with experiments. The capability of CFD-DEM approach to efficiently describe the global bed dynamics for fluidized bed of rod-like particles is demonstrated.

  2. Monosodium titanate particle characterization

    International Nuclear Information System (INIS)

    Chandler, G.T.; Hobbs, D.T.

    1993-01-01

    A characterization study was performed on monosodium titanate (MST) particles to determine the effect of high shear forces expected from the In-Tank Precipitation (ITP) process pumps on the particle size distribution. The particles were characterized using particle size analysis and scanning electron microscopy (SEM). No significant changes in particle size distributions were observed between as-received MST and after 2--4 hours of shearing. Both as-received and sheared MST particles contained a large percentage of porosity with pore sizes on the order of 500 to 2,000 Angstroms. Because of the large percentage of porosity, the overall surface area of the MST is dominated by the internal surfaces. The uranium and plutonium species present in the waste solution will have access to both interior and exterior surfaces. Therefore, uranium and plutonium loading should not be a strong function of MST particle size

  3. Radiative decay of surface plasmons on nonspherical silver particles

    International Nuclear Information System (INIS)

    Little, J.W.; Ferrell, T.L.; Callcott, T.A.; Arakawa, E.T.

    1982-01-01

    We have studied the radiation emitted by electron-bombarded silver particles. Electron micrographs have shown that the particles, obtained by heating thin (5 nm) silver films, were oblate (flattened) with minor axes aligned along the substrate normal. The characteristic wavelength obtained by bombarding these particles with 15-keV electrons was found to vary with angle of photon emission. We have modeled this wavelength shift as a result of the mixture of radiation from dipole and quadrupole surface-plasmon oscillations on oblate spheroids. Experimental observations of the energy, polarization, and angular distribution of the emitted radiation are in good agreement with theoretical calculations

  4. Quasi-three level Nd:YLF fundamental and Raman laser operating under 872-nm and 880-nm direct diode pumping

    Science.gov (United States)

    Wetter, Niklaus U.; Bereczki, Allan; Paes, João. Pedro Fonseca

    2018-02-01

    Nd:YLiF4 is the gain material of choice whenever outstanding beam quality or a birefringent gain material is necessary such as in certain applications for terahertz radiation or dual-frequency mode-locking. However, for high power CW applications the material is hampered by a low thermal fracture threshold. This problem can be mitigated by special 2D pump set-ups or by keeping the quantum defect to a minimum. Direct pumping into the upper laser level of Nd:YLiF4 is usually performed at 880 nm. For quasi-three level laser emission at 908 nm, direct pumping at this wavelength provides a high quantum defect of 0.97, which allows for very high CW pump powers. Although the direct pumping transition to the upper laser state at 872 nm has a slightly smaller quantum defect of 0.96, its pump absorption cross section along the c-axis is 50% higher than at 880 nm, leading to a higher absorption efficiency. In this work we explore, for the first time to our knowledge, 908 nm lasing under 872 nm diode pumping and compare the results with 880 nm pumping for quasicw and cw operation. By inserting a KGW crystal in the cavity, Raman lines at 990 nm and 972 nm were obtained for the first time from a directly pumped 908 nm Nd:YLF fundamental laser for both quasi-cw and cw conditions.

  5. Single-particle characterization of ice-nucleating particles and ice particle residuals sampled by three different techniques

    Science.gov (United States)

    Worringen, A.; Kandler, K.; Benker, N.; Dirsch, T.; Mertes, S.; Schenk, L.; Kästner, U.; Frank, F.; Nillius, B.; Bundke, U.; Rose, D.; Curtius, J.; Kupiszewski, P.; Weingartner, E.; Vochezer, P.; Schneider, J.; Schmidt, S.; Weinbruch, S.; Ebert, M.

    2015-04-01

    -400 nm in geometric diameter. In a few cases, a second supermicron maximum was identified. Soot/carbonaceous material and metal oxides were present mainly in the sub-micrometer range. Silicates and Ca-rich particles were mainly found with diameters above 1 μm (using ISI and FINCH), in contrast to the Ice-CVI which also sampled many submicron particles of both groups. Due to changing meteorological conditions, the INP/IPR composition was highly variable if different samples were compared. Thus, the observed discrepancies between the different separation techniques may partly result from the non-parallel sampling. The differences of the particle group relative number abundance as well as the mixing state of INP/IPR clearly demonstrate the need of further studies to better understand the influence of the separation techniques on the INP/IPR chemical composition. Also, it must be concluded that the abundance of contamination artifacts in the separated INP and IPR is generally large and should be corrected for, emphasizing the need for the accompanying chemical measurements. Thus, further work is needed to allow for routine operation of the three separation techniques investigated.

  6. Time history of diesel particle deposition in cylindrical dielectric barrier discharge reactors

    International Nuclear Information System (INIS)

    Talebizadeh, P.; Rahimzadeh, H.; Ahmadi, G.; Brown, R.; Inthavong, K.

    2016-01-01

    Non-thermal plasma (NTP) treatment reactors have recently been developed for elimination of diesel particulate matter for reducing both the mass and number concentration of particles. The role of the plasma itself is obscured by the phenomenon of particle deposition on the reactor surface. Therefore, in this study, the Lagrangian particle transport model is used to simulate the dispersion and deposition of nano-particles in the range of 5 to 500 nm in a NTP reactor in the absence of an electric field. A conventional cylindrical dielectric barrier discharge reactor is selected for the analysis. Brownian diffusion, gravity and Saffman lift forces were included in the simulations, and the deposition efficiencies of different sized diesel particles were studied. The results show that for the studied particle diameters, the effect of Saffman lift is negligible and gravity only affects the motion of particles with a diameter of 500 nm or larger. Time histories of particle transport and deposition were evaluated for one-time injection and a continuous (multiple-time) injection. The results show that the number of deposited particles for one-time injection is identical to the number of deposited particles for multiple-time injections when adjusted with the shift in time. Furthermore, the maximum number of escaped particles occurs at 0.045 s after the injection for all particle diameters. The presented results show that some particle reduction previously ascribed to plasma treatment has ignored contributions from the surface deposition.

  7. Time history of diesel particle deposition in cylindrical dielectric barrier discharge reactors

    Energy Technology Data Exchange (ETDEWEB)

    Talebizadeh, P.; Rahimzadeh, H., E-mail: rahimzad@aut.ac.ir [Amirkabir University of Technology, Department of Mechanical Engineering (Iran, Islamic Republic of); Ahmadi, G. [Clarkson University, Department of Mechanical and Aeronautical Engineering (United States); Brown, R. [Queensland University of Technology, Biofuel Engine Research Facility (Australia); Inthavong, K. [RMIT University, School of Aerospace, Mechanical and Manufacturing Engineering (Australia)

    2016-12-15

    Non-thermal plasma (NTP) treatment reactors have recently been developed for elimination of diesel particulate matter for reducing both the mass and number concentration of particles. The role of the plasma itself is obscured by the phenomenon of particle deposition on the reactor surface. Therefore, in this study, the Lagrangian particle transport model is used to simulate the dispersion and deposition of nano-particles in the range of 5 to 500 nm in a NTP reactor in the absence of an electric field. A conventional cylindrical dielectric barrier discharge reactor is selected for the analysis. Brownian diffusion, gravity and Saffman lift forces were included in the simulations, and the deposition efficiencies of different sized diesel particles were studied. The results show that for the studied particle diameters, the effect of Saffman lift is negligible and gravity only affects the motion of particles with a diameter of 500 nm or larger. Time histories of particle transport and deposition were evaluated for one-time injection and a continuous (multiple-time) injection. The results show that the number of deposited particles for one-time injection is identical to the number of deposited particles for multiple-time injections when adjusted with the shift in time. Furthermore, the maximum number of escaped particles occurs at 0.045 s after the injection for all particle diameters. The presented results show that some particle reduction previously ascribed to plasma treatment has ignored contributions from the surface deposition.

  8. Temperature and particle-size dependent viscosity data for water-based nanofluids - Hysteresis phenomenon

    International Nuclear Information System (INIS)

    Nguyen, C.T.; Desgranges, F.; Roy, G.; Galanis, N.; Mare, T.; Boucher, S.; Angue Mintsa, H.

    2007-01-01

    In the present paper, we have investigated experimentally the influence of both the temperature and the particle size on the dynamic viscosities of two particular water-based nanofluids, namely water-Al 2 O 3 and water-CuO mixtures. The measurement of nanofluid dynamic viscosities was accomplished using a 'piston-type' calibrated viscometer based on the Couette flow inside a cylindrical measurement chamber. Data were collected for temperatures ranging from ambient to 75 deg. C, for water-Al 2 O 3 mixtures with two different particle diameters, 36 nm and 47 nm, as well as for water-CuO nanofluid with 29 nm particle size. The results show that for particle volume fractions lower than 4%, viscosities corresponding to 36 nm and 47 nm particle-size alumina-water nanofluids are approximately identical. For higher particle fractions, viscosities of 47 nm particle-size are clearly higher than those of 36 nm size. Viscosities corresponding to water-oxide copper are the highest among the nanofluids tested. The temperature effect has been investigated thoroughly. A more complete viscosity data base is presented for the three nanofluids considered, with several experimental correlations proposed for low particle volume fractions. It has been found that the application of Einstein's formula and those derived from the linear fluid theory seems not to be appropriate for nanofluids. The hysteresis phenomenon on viscosity measurement, which is believed to be the first observed for nanofluids, has raised serious concerns regarding the use of nanofluids for heat transfer enhancement purposes

  9. A 3D particle Monte Carlo approach to studying nucleation

    Science.gov (United States)

    Köhn, Christoph; Enghoff, Martin Bødker; Svensmark, Henrik

    2018-06-01

    The nucleation of sulphuric acid molecules plays a key role in the formation of aerosols. We here present a three dimensional particle Monte Carlo model to study the growth of sulphuric acid clusters as well as its dependence on the ambient temperature and the initial particle density. We initiate a swarm of sulphuric acid-water clusters with a size of 0.329 nm with densities between 107 and 108 cm-3 at temperatures between 200 and 300 K and a relative humidity of 50%. After every time step, we update the position of particles as a function of size-dependent diffusion coefficients. If two particles encounter, we merge them and add their volumes and masses. Inversely, we check after every time step whether a polymer evaporates liberating a molecule. We present the spatial distribution as well as the size distribution calculated from individual clusters. We also calculate the nucleation rate of clusters with a radius of 0.85 nm as a function of time, initial particle density and temperature. The nucleation rates obtained from the presented model agree well with experimentally obtained values and those of a numerical model which serves as a benchmark of our code. In contrast to previous nucleation models, we here present for the first time a code capable of tracing individual particles and thus of capturing the physics related to the discrete nature of particles.

  10. TS-1 supported highly dispersed sub-5 nm gold nanoparticles toward direct propylene epoxidation using H2 and O2

    Science.gov (United States)

    Li, Naixu; Chen, Yong; Shen, Quanhao; Yang, Bin; Liu, Ming; Wei, Lingfei; Tian, Wei; Zhou, Jiancheng

    2018-05-01

    We report a simple and efficient method for the preparation of highly dispersed Au nanoparticles (< 5 nm) on TS-1 substrate. The synthesis relies on the use of NaBH4 as a reductant for rapid Au atom generation, as well as PVA as a capping agent confining the particle size and dispersion. The samples were characterized by N2 physisorption, inductively coupled plasma mass spectrometry, power X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, CO pulse chemisorption and thermogravimetric analysis. The size of Au particles can be controlled in the range of 3-5 nm. The supported catalyst shows both good activity and selectivity for propylene oxide (PO) generation from direct propylene epoxidation. An optimal performance with PO formation rate of 102.94 gPO h-1 kg-1cat and selectivity of 84.83% is achieved over 2.0 wt% Au/TS-1 catalyst, which is prepared by controlling PVA/Au3+ mass ratio of 1.5/1 and NaBH4/Au3+ mole ratio of 5/1. After 50 h test at 200 °C, no significant decrement of both catalytic activity and PO selectivity can be observed, indicating the excellent thermally stability of the catalyst. Furthermore, a possible reaction mechanism is described on basis of the previous researches and our experimental results.

  11. Comparison of the ablation ability of nucleus pulposus after 1,064 nm Nd:YAG laser and 980 nm diode laser radiation.

    Science.gov (United States)

    Yin, Jian; Han, Zhengfeng; Guo, Baofeng; Guo, Han; Zhang, Tongtong; Zeng, Yanjun; Ren, Longxi

    2015-07-01

    To compare the ablation ability of nucleus pulposus after 1,064 nm Nd:YAG laser and 980 nm diode laser radiation. Goat spine specimen (GSS) was radiated using Nd:YAG laser and 980 nm diode laser and then divided into five groups based on the final energy--200, 400, 600, 800 and 1,000 J groups. The ablation quality of nucleus pulposus after radiation was recorded. The ablation quality of GSS was greater at higher radiation energies in both lasers. When compared at the same energy level, the ablation quality of GSS was greater in 980 nm diode laser than in 1,064 nm Nd:YAG laser. Statistical significance was observed in 200 and 400 J groups (P diode laser showed better ablation ability than 1,064 nm Nd:YAG laser.

  12. Picosecond laser damage of fused silica at 355 nm

    International Nuclear Information System (INIS)

    Meng Xiangjie; Liu Hongjie; Wang Fang; Zhang Zhen; An Xinyou; Huang Jin; Jiang Xiaodong; Wu Weidong; Ren Weiyi

    2013-01-01

    This paper studies the initiated damage threshold, the damage morphology and the subsequent damage growth on fused silica's input-surface and exit-surface under picosecond laser irradiation at 355 nm. Defects induced fluorescence on surface of the optical component is observed. The results demonstrate a significant dependence of the initiated damage on pulse duration and surface defects, and that of the damage growth on self-focusing, sub-surface defects. The damage-threshold is 3.98 J/cm 2 of input surface and 2.91 J/cm 2 of exit surface. The damage morphologies are quite different between input surface and exit surface. Slow growth behavior appears for the diameter of exit-surface and linear growth one for the depth of exit-surface in the lateral side of damage site with the increase of shot number. Defects have changed obviously compared with nanosecond laser damage in the damage area. Several main reasons such as electric intensification and self-focusing for the observed initiated damage and damage growth behavior are discussed. (authors)

  13. Nantenna for Standard 1550 nm Optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Waleed Tariq Sethi

    2016-01-01

    Full Text Available Nanoscale transmission and reception technologies will play a vital role and be part of the next generation communication networks. This applies for all application fields including imaging, health, biosensing, civilian, and military communications. The detection of light frequency using nanooptical antennas may possibly become a good competitor to the semiconductor based photodetector because of the simplicity of integration, cost, and inherent capability to detect the phase and amplitude instead of power only. In this paper, authors propose simulated design of a hexagonal dielectric loaded nantenna (HDLN and explore its potential benefits at the standard optical C-band (1550 nm. The proposed nantenna consists of “Ag-SiO2-Ag” structure, consisting of “Si” hexagonal dielectric with equal lengths fed by “Ag” nanostrip transmission line. The simulated nantenna achieves an impedance bandwidth of 3.7% (190.9 THz–198.1 THz and a directivity of 8.6 dBi, at a center frequency of 193.5 THz, covering most of the ITU-T standard optical transmission window (C-band. The hexagonal dielectric nantenna produces HE20δ modes and the wave propagation is found to be end-fire. The efficiency of the nantenna is proven via numerical expressions, thus making the proposed design viable for nanonetwork communications.

  14. Electrical control of antiferromagnetic metal up to 15 nm

    Science.gov (United States)

    Zhang, PengXiang; Yin, GuFan; Wang, YuYan; Cui, Bin; Pan, Feng; Song, Cheng

    2016-08-01

    Manipulation of antiferromagnetic (AFM) spins by electrical means is on great demand to develop the AFM spintronics with low power consumption. Here we report a reversible electrical control of antiferromagnetic moments of FeMn up to 15 nm, using an ionic liquid to exert a substantial electric-field effect. The manipulation is demonstrated by the modulation of exchange spring in [Co/Pt]/FeMn system, where AFM moments in FeMn pin the magnetization rotation of Co/Pt. By carrier injection or extraction, the magnetic anisotropy of the top layer in FeMn is modulated to influence the whole exchange spring and then passes its influence to the [Co/Pt]/FeMn interface, through a distance up to the length of exchange spring that fully screens electric field. Comparing FeMn to IrMn, despite the opposite dependence of exchange bias on gate voltages, the same correlation between carrier density and exchange spring stiffness is demonstrated. Besides the fundamental significance of modulating the spin structures in metallic AFM via all-electrical fashion, the present finding would advance the development of low-power-consumption AFM spintronics.

  15. Synchrotron Radiation Lithography for Manufacturing Integrated Circuits Beyond 100 nm.

    Science.gov (United States)

    Kinoshita, H; Watanabe, T; Niibe, M

    1998-05-01

    Extreme ultraviolet lithography is a powerful tool for printing features of 0.1 micro m and below; in Japan and the USA there is a growing tendency to view it as the wave of the future. With Schwarzschild optics, replication of a 0.05 micro m pattern has been demonstrated in a 25 micro m square area. With a two-aspherical-mirror system, a 0.15 micro m pattern has been replicated in a ring slit area of 20 mm x 0.4 mm; a combination of this system with illumination optics and synchronized mask and wafer stages has enabled the replication of a 0.15 micro m pattern in an area of 10 mm x 12.5 mm. Furthermore, in the USA, the Sandia National Laboratory has succeeded in fabricating a fully operational NMOS transistor with a gate length of 0.1 micro m. The most challenging problem is the fabrication of mirrors with the required figure error of 0.28 nm. However, owing to advances in measurement technology, mirrors can now be made to a precision that almost satisfies this requirement. Therefore, it is time to move into a rapid development phase in order to obtain a system ready for practical use by the year 2004. In this paper the status of individual technologies is discussed in light of this situation, and future requirements for developing a practical system are considered.

  16. High-speed stimulated Brillouin scattering spectroscopy at 780 nm

    Directory of Open Access Journals (Sweden)

    Itay Remer

    2016-09-01

    Full Text Available We demonstrate a high-speed stimulated Brillouin scattering (SBS spectroscopy system that is able to acquire stimulated Brillouin gain point-spectra in water samples and Intralipid tissue phantoms over 2 GHz within 10 ms and 100 ms, respectively, showing a 10-100 fold increase in acquisition rates over current frequency-domain SBS spectrometers. This improvement was accomplished by integrating an ultra-narrowband hot rubidium-85 vapor notch filter in a simplified frequency-domain SBS spectrometer comprising nearly counter-propagating continuous-wave pump-probe light at 780 nm and conventional single-modulation lock-in detection. The optical notch filter significantly suppressed stray pump light, enabling detection of stimulated Brillouin gain spectra with substantially improved acquisition times at adequate signal-to-noise ratios (∼25 dB in water samples and ∼15 dB in tissue phantoms. These results represent an important step towards the use of SBS spectroscopy for high-speed measurements of Brillouin gain resonances in scattering and non-scattering samples.

  17. Observations of thunderstorm-related 630 nm airglow depletions

    Science.gov (United States)

    Kendall, E. A.; Bhatt, A.

    2015-12-01

    The Midlatitude All-sky imaging Network for Geophysical Observations (MANGO) is an NSF-funded network of 630 nm all-sky imagers in the continental United States. MANGO will be used to observe the generation, propagation, and dissipation of medium and large-scale wave activity in the subauroral, mid and low-latitude thermosphere. This network is actively being deployed and will ultimately consist of nine all-sky imagers. These imagers form a network providing continuous coverage over the western United States, including California, Oregon, Washington, Utah, Arizona and Texas extending south into Mexico. This network sees high levels of both medium and large scale wave activity. Apart from the widely reported northeast to southwest propagating wave fronts resulting from the so called Perkins mechanism, this network observes wave fronts propagating to the west, north and northeast. At least three of these anomalous events have been associated with thunderstorm activity. Imager data has been correlated with both GPS data and data from the AIRS (Atmospheric Infrared Sounder) instrument on board NASA's Earth Observing System Aqua satellite. We will present a comprehensive analysis of these events and discuss the potential thunderstorm source mechanism.

  18. MECHANISMS OF ACTION OF INHALED FIBERS, PARTICLES AND NANOPARTICLES IN LUNG AND CARDIOVASCULAR DISEASES

    Science.gov (United States)

    ABSTRACT: A symposium on the mechanisms of action of inhaled airborne particulate matter (PM),pathogenic particles and fibers such as silica and asbestos, and nanomaterials, defined as synthetic particles or fibers less than 100 nm in diameter, was held on October 27 and 28,...

  19. A method for detecting the presence of organic fraction in nucleation mode sized particles

    Directory of Open Access Journals (Sweden)

    P. Vaattovaara

    2005-01-01

    Full Text Available New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm and the lower end of Aitken mode particles (d≤50 nm is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer method to shed light on the presence of an organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10 nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various oxidized organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.

  20. Size effect of added LaB6 particles on optical properties of LaB6/Polymer composites

    International Nuclear Information System (INIS)

    Yuan Yifei; Zhang Lin; Hu Lijie; Wang Wei; Min Guanghui

    2011-01-01

    Modified LaB 6 particles with sizes ranging from 50 nm to 400 nm were added into polymethyl methacrylate (PMMA) matrix in order to investigate the effect of added LaB 6 particles on optical properties of LaB 6 /PMMA composites. Method of in-situ polymerization was applied to prepare PMMA from raw material—methyl methacrylate (MMA), a process during which LaB 6 particles were dispersed in MMA. Ultraviolet–visible–near infrared (UV–vis–NIR) absorption spectrum was used to study optical properties of the as-prepared materials. The difference in particle size could apparently affect the composites' absorption of visible light around wavelength of 600 nm. Added LaB 6 particles with size of about 70 nm resulted in the best optical properties among these groups of composites. - Graphical abstract: 70 nm LaB 6 particles resulted in the best performance on absorption of VIS and NIR, which could not be apparently achieved by LaB 6 particles beyond nano-scale. Highlights: ► LaB 6 /PMMA composites were prepared using the method of in-situ polymerization. ► LaB 6 particles added in MMA prolonged the time needed for its pre-polymerization. ► Nanosized LaB 6 particles could obviously absorb much NIR but little VIS.

  1. Lecture II. Charmed particle spectroscopy

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The discussion of charmed particle spectroscopy covers the particle properties and interrelations from a charmed quark composition point of view including SU(4)-symmetry generalities, mesons, baryons, charmed particle masses, and decays of charmed particles. 6 references

  2. Magnetic-luminescent spherical particles synthesized by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Michel, Norma L; Hirata, Gustavo A; Flores, Dora L

    2015-01-01

    The combination of magnetic and luminescent properties in a single particle system, opens-up a wide range of potential applications in biotechnology and biomedicine. In this work, we performed the synthesis of magnetic-luminescent Gd 2 O 3 :Eu 3+ @Fe 2 O 3 particles by ultrasonic spray pyrolysis performed in a tubular furnace. In order to achieve the composite formation, commercial superparamagnetic Fe 3 O 4 nanoparticles were coated with a luminescent Eu 3+ -doped Gd 2 O 3 shell in a low-cost one-step process. The spray pyrolysis method yields deagglomerated spherical shape magneto/luminescent particles. The photoluminescence spectra under UV excitation (λ Exc = 265 nm) of the magnetic Gd 2 O 3 :Eu 3+ @Fe 2 O 3 compound showed the characteristic red emission of Eu 3+ (λ Em = 612 nm). This magneto/luminescent system will find applications in biomedicine and biotechnology. (paper)

  3. Physical characterization of diesel exhaust nucleation mode particles

    Energy Technology Data Exchange (ETDEWEB)

    Lahde, T.

    2013-11-01

    An increasing concern of the adverse health effects of aerosol particles is forcing the combustion engine industry to develop engines with lower particle emissions. The industry has put most of their efforts into soot control and has achieved a significant reduction in diesel exhaust particle mass. Nevertheless, it is not clear that the large particles, dominating the mass, cause the harmfulness of the exhaust particles in the biological interaction. Nowadays, the harmful potential of diesel exhaust particles often connects with the particle surface area, and the view has turned to particle number below 100 nm size range. Unfortunately, the achieved low exhaust particle mass does not necessarily imply a low particle number. This text focuses on the physical characteristics of diesel exhaust nucleation model particles. The volatility characteristics and the electrical charge state of the particles are studied first. Second, the relation between the nonvolatile nucleation mode emissions and the soot, the nitrogen oxide (NO{sub x}) emissions and the engine parameters are covered. The nucleation mode particles had distinctively different physical characteristics with different after-treatment systems. The nucleation mode was volatile and electrically neutral with a diesel particle filter after-treatment system. Without an after-treatment system or with an after-treatment system with low particle removal efficiency, the nucleation mode was partly nonvolatile and included an electrical charge. The difference suggests different formation routes for the nucleation particles with different after-treatment systems. The existence of the nonvolatile nucleation mode particles also affected the soot mode charge state. The soot charge state was positively biased when the nonvolatile nucleation mode was detected but slightly negatively biased when the nonvolatile nucleation mode was absent. The nonvolatile nucleation mode was always negatively biased. This electrical charge

  4. Diode-pumped continuous-wave eye-safe Nd:YAG laser at 1415 nm.

    Science.gov (United States)

    Lee, Hee Chul; Byeon, Sung Ug; Lukashev, Alexei

    2012-04-01

    We describe the output performance of the 1415 nm emission in Nd:YAG in a plane-concave cavity under traditional pumping into the 4F5/2 level (808 nm) and direct in-band pumping into the 4F3/2 level (885 nm). An end-pumped Nd:YAG laser yielded maximum cw output power of 6.3 W and 4.2 W at 885 nm and 808 nm laser diode (LD) pumping, respectively. To the best of our knowledge, this is the highest output power of a LD-pumped 1415 nm laser.

  5. Broadband light generation at ~1300 nm through spectrally recoiled solitons and dispersive waves

    DEFF Research Database (Denmark)

    Falk, Peter Andreas; Frosz, Michael Henoch; Bang, Ole

    2008-01-01

    We experimentally study the generation of broadband light at ~1300 nm from an 810 nm Ti:sapphire femtosecond pump laser. We use two photonic crystal fibers with a second infrared zero-dispersion wavelength (λZ2) and compare the efficiency of two schemes: in one fiber λZ2=1400 nm and the light...... at 1300 nm is composed of spectrally recoiled solitons; in the other fiber λZ2=1200 nm and the light at 1300 nm is composed of dispersive waves....

  6. Evolution of particle composition in CLOUD nucleation experiments

    Directory of Open Access Journals (Sweden)

    H. Keskinen

    2013-06-01

    Full Text Available Sulphuric acid, ammonia, amines, and oxidised organics play a crucial role in nanoparticle formation in the atmosphere. In this study, we investigate the composition of nucleated nanoparticles formed from these compounds in the CLOUD (Cosmics Leaving Outdoor Droplets chamber experiments at CERN (Centre européen pour la recherche nucléaire. The investigation was carried out via analysis of the particle hygroscopicity, ethanol affinity, oxidation state, and ion composition. Hygroscopicity was studied by a hygroscopic tandem differential mobility analyser and a cloud condensation nuclei counter, ethanol affinity by an organic differential mobility analyser and particle oxidation level by a high-resolution time-of-flight aerosol mass spectrometer. The ion composition was studied by an atmospheric pressure interface time-of-flight mass spectrometer. The volume fraction of the organics in the particles during their growth from sizes of a few nanometers to tens of nanometers was derived from measured hygroscopicity assuming the Zdanovskii–Stokes–Robinson relationship, and compared to values gained from the spectrometers. The ZSR-relationship was also applied to obtain the measured ethanol affinities during the particle growth, which were used to derive the volume fractions of sulphuric acid and the other inorganics (e.g. ammonium salts. In the presence of sulphuric acid and ammonia, particles with a mobility diameter of 150 nm were chemically neutralised to ammonium sulphate. In the presence of oxidation products of pinanediol, the organic volume fraction of freshly nucleated particles increased from 0.4 to ~0.9, with an increase in diameter from 2 to 63 nm. Conversely, the sulphuric acid volume fraction decreased from 0.6 to 0.1 when the particle diameter increased from 2 to 50 nm. The results provide information on the composition of nucleated aerosol particles during their growth in the presence of various combinations of sulphuric acid

  7. Particle size dependence of biogenic secondary organic aerosol molecular composition

    Science.gov (United States)

    Tu, Peijun; Johnston, Murray V.

    2017-06-01

    Formation of secondary organic aerosol (SOA) is initiated by the oxidation of volatile organic compounds (VOCs) in the gas phase whose products subsequently partition to the particle phase. Non-volatile molecules have a negligible evaporation rate and grow particles at their condensation rate. Semi-volatile molecules have a significant evaporation rate and grow particles at a much slower rate than their condensation rate. Particle phase chemistry may enhance particle growth if it transforms partitioned semi-volatile molecules into non-volatile products. In principle, changes in molecular composition as a function of particle size allow non-volatile molecules that have condensed from the gas phase (a surface-limited process) to be distinguished from those produced by particle phase reaction (a volume-limited process). In this work, SOA was produced by β-pinene ozonolysis in a flow tube reactor. Aerosol exiting the reactor was size-selected with a differential mobility analyzer, and individual particle sizes between 35 and 110 nm in diameter were characterized by on- and offline mass spectrometry. Both the average oxygen-to-carbon (O / C) ratio and carbon oxidation state (OSc) were found to decrease with increasing particle size, while the relative signal intensity of oligomers increased with increasing particle size. These results are consistent with oligomer formation primarily in the particle phase (accretion reactions, which become more favored as the volume-to-surface-area ratio of the particle increases). Analysis of a series of polydisperse SOA samples showed similar dependencies: as the mass loading increased (and average volume-to-surface-area ratio increased), the average O / C ratio and OSc decreased, while the relative intensity of oligomer ions increased. The results illustrate the potential impact that particle phase chemistry can have on biogenic SOA formation and the particle size range where this chemistry becomes important.

  8. Particle size dependence of biogenic secondary organic aerosol molecular composition

    Directory of Open Access Journals (Sweden)

    P. Tu

    2017-06-01

    Full Text Available Formation of secondary organic aerosol (SOA is initiated by the oxidation of volatile organic compounds (VOCs in the gas phase whose products subsequently partition to the particle phase. Non-volatile molecules have a negligible evaporation rate and grow particles at their condensation rate. Semi-volatile molecules have a significant evaporation rate and grow particles at a much slower rate than their condensation rate. Particle phase chemistry may enhance particle growth if it transforms partitioned semi-volatile molecules into non-volatile products. In principle, changes in molecular composition as a function of particle size allow non-volatile molecules that have condensed from the gas phase (a surface-limited process to be distinguished from those produced by particle phase reaction (a volume-limited process. In this work, SOA was produced by β-pinene ozonolysis in a flow tube reactor. Aerosol exiting the reactor was size-selected with a differential mobility analyzer, and individual particle sizes between 35 and 110 nm in diameter were characterized by on- and offline mass spectrometry. Both the average oxygen-to-carbon (O ∕ C ratio and carbon oxidation state (OSc were found to decrease with increasing particle size, while the relative signal intensity of oligomers increased with increasing particle size. These results are consistent with oligomer formation primarily in the particle phase (accretion reactions, which become more favored as the volume-to-surface-area ratio of the particle increases. Analysis of a series of polydisperse SOA samples showed similar dependencies: as the mass loading increased (and average volume-to-surface-area ratio increased, the average O ∕ C ratio and OSc decreased, while the relative intensity of oligomer ions increased. The results illustrate the potential impact that particle phase chemistry can have on biogenic SOA formation and the particle size range where this chemistry becomes

  9. Effect of indirect non-thermal plasma on particle size distribution and composition of diesel engine particles

    Science.gov (United States)

    Linbo, GU; Yixi, CAI; Yunxi, SHI; Jing, WANG; Xiaoyu, PU; Jing, TIAN; Runlin, FAN

    2017-11-01

    To explore the effect of the gas source flow rate on the actual diesel exhaust particulate matter (PM), a test bench for diesel engine exhaust purification was constructed, using indirect non-thermal plasma technology. The effects of different gas source flow rates on the quantity concentration, composition, and apparent activation energy of PM were investigated, using an engine exhaust particle sizer and a thermo-gravimetric analyzer. The results show that when the gas source flow rate was large, not only the maximum peak quantity concentrations of particles had a large drop, but also the peak quantity concentrations shifted to smaller particle sizes from 100 nm to 80 nm. When the gas source flow rate was 10 L min-1, the total quantity concentration greatly decreased where the removal rate of particles was 79.2%, and the variation of the different mode particle proportion was obvious. Non-thermal plasma (NTP) improved the oxidation ability of volatile matter as well as that of solid carbon. However, the NTP gas source rate had little effects on oxidation activity of volatile matter, while it strongly influenced the oxidation activity of solid carbon. Considering the quantity concentration and oxidation activity of particles, a gas source flow rate of 10 L min-1 was more appropriate for the purification of particles.

  10. Synthesis of Brushite Particles in Reverse Microemulsions of the Biosurfactant Surfactin

    Directory of Open Access Journals (Sweden)

    Young-Fo Chang

    2011-06-01

    Full Text Available In this study the “green chemistry” use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion technique with surfactin was used to produce nanocrystalline brushite particles. Structural diversity (analyzed by SEM and TEM resulted from different water to surfactin ratios (W/S; 250, 500, 1000 and 40,000. The particle sizes were found to be in the 16–200 nm range. Morphological variety was observed in the as-synthesized microemulsions, which consisted of nanospheres (~16 nm in diameter and needle-like (8–14 nm in diameter and 80–100 nm in length noncalcinated particles. However, the calcinated products included nanospheres (50–200 nm in diameter, oval (~300 nm in diameter and nanorod (200–400 nm in length particles. FTIR and XRD analysis confirmed the formation of brushite nanoparticles in the as-synthesized products, while calcium pyrophosphate was produced after calcination. These results indicate that the reverse microemulsion technique using surfactin is a green process suitable for the synthesis of nanoparticles.

  11. Synthesis of brushite particles in reverse microemulsions of the biosurfactant surfactin.

    Science.gov (United States)

    Maity, Jyoti Prakash; Lin, Tz-Jiun; Cheng, Henry Pai-Heng; Chen, Chien-Yen; Reddy, A Satyanarayana; Atla, Shashi B; Chang, Young-Fo; Chen, Hau-Ren; Chen, Chien-Cheng

    2011-01-01

    In this study the "green chemistry" use of the biosurfactant surfactin for the synthesis of calcium phosphate using the reverse microemulsion technique was demonstrated. Calcium phosphates are bioactive materials that are a major constituent of human teeth and bone tissue. A reverse microemulsion technique with surfactin was used to produce nanocrystalline brushite particles. Structural diversity (analyzed by SEM and TEM) resulted from different water to surfactin ratios (W/S; 250, 500, 1000 and 40,000). The particle sizes were found to be in the 16-200 nm range. Morphological variety was observed in the as-synthesized microemulsions, which consisted of nanospheres (~16 nm in diameter) and needle-like (8-14 nm in diameter and 80-100 nm in length) noncalcinated particles. However, the calcinated products included nanospheres (50-200 nm in diameter), oval (~300 nm in diameter) and nanorod (200-400 nm in length) particles. FTIR and XRD analysis confirmed the formation of brushite nanoparticles in the as-synthesized products, while calcium pyrophosphate was produced after calcination. These results indicate that the reverse microemulsion technique using surfactin is a green process suitable for the synthesis of nanoparticles.

  12. Viscous properties of ferrofluids containing both micrometer-size magnetic particles and fine needle-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Ido, Yasushi, E-mail: ido.yasushi@nitech.ac.jp [Department of Electric and Mechanical Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya (Japan); Nishida, Hitoshi [Department of Electrical and Control Systems Engineering, National Institute of Technology, Toyama College, 13 Hongo-cho, Toyama (Japan); Iwamoto, Yuhiro [Department of Electric and Mechanical Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya (Japan); Yokoyama, Hiroki [KYB Corporation, 2-4-1 Hamamatsu-cho, Minato-ku, Tokyo (Japan)

    2017-06-01

    Ferrofluids containing both micrometer-size spherical magnetic particles and nanometer-size needle-like nonmagnetic hematite particles were newly produced. Average length of long axis of the needle-like nonmagnetic particles was 194 nm and the aspect ratio was 8.3. Shear stress and viscosity were measured using the rheometer with the additional equipment for viscosity measurements in the presence of magnetic field. When the total volume fraction of particles in the fluid is constant (0.30), there is the specific mixing ratio of the particles to increase viscosity of the fluid drastically in the absence of magnetic field due to the percolation phenomenon. The fluid of the specific mixing ratio shows solid-like behavior even in the absence of magnetic field. Mixing the needle-like nonmagnetic particles causes strong yield stress and strong viscous force in the presence of magnetic field. - Highlights: • Viscous properties of new magnetic functional fluids were studied experimentally. • The new fluids contain spherical magnetic particles and needle-like particles. • Percolation occurs in the fluid of specific mixing ratio of particles without field. • The fluid of the specific mixing ratio behaves like solid without field. • Mixing needle-like particles causes strong yield stress of the fluid in the field.

  13. Two transistor cluster DICE Cells with the minimum area for a hardened 28-nm CMOS and 65-nm SRAM layout design

    International Nuclear Information System (INIS)

    Stenin, V.Ya.; Stepanov, P.V.

    2015-01-01

    A hardened DICE cell layout design is based on the two spaced transistor clusters of the DICE cell each consisting of four transistors. The larger the distance between these two CMOS transistor clusters, the more robust the hardened DICE SRAM to Single Event Upsets. Some versions of the 28-nm and 65-nm DICE CMOS SRAM block composition have been suggested with minimum cluster distances of 2.27-2.32 mkm. The area of hardened 28-nm DICE CMOS cells is larger than the area of 28-nm 6T CMOS cells by a factor of 2.1 [ru

  14. Methods for forming particles

    Science.gov (United States)

    Fox, Robert V.; Zhang, Fengyan; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin

    2016-06-21

    Single source precursors or pre-copolymers of single source precursors are subjected to microwave radiation to form particles of a I-III-VI.sub.2 material. Such particles may be formed in a wurtzite phase and may be converted to a chalcopyrite phase by, for example, exposure to heat. The particles in the wurtzite phase may have a substantially hexagonal shape that enables stacking into ordered layers. The particles in the wurtzite phase may be mixed with particles in the chalcopyrite phase (i.e., chalcopyrite nanoparticles) that may fill voids within the ordered layers of the particles in the wurtzite phase thus produce films with good coverage. In some embodiments, the methods are used to form layers of semiconductor materials comprising a I-III-VI.sub.2 material. Devices such as, for example, thin-film solar cells may be fabricated using such methods.

  15. LHCb unveils new particles

    CERN Multimedia

    Stefania Pandolfi

    2016-01-01

    The LHCb collaboration announces the observation of four “exotic” particles from its analysis of the LHC data.   The LHCb experimental cavern. On 28 June, the LHCb collaboration reported the observation of three new "exotic" particles and confirmation of the existence of a fourth one in data from the LHC. These particles each appear to be formed by four quarks (the fundamental constituents of the matter inside all the atoms of the universe): two quarks and two antiquarks (that is, a tetraquark). Due to their non-standard quark content, the newly observed particles have been included in the broad category of so-called exotic particles, although their exact theoretical interpretation is still under study.            The quark model, proposed by Murray Gell-Mann and George Zweig in 1964, is considered to be the most valid scheme for the classification of hadrons (all the composite particles) that has been fou...

  16. Particle Swarm Optimization

    Science.gov (United States)

    Venter, Gerhard; Sobieszczanski-Sobieski Jaroslaw

    2002-01-01

    The purpose of this paper is to show how the search algorithm known as particle swarm optimization performs. Here, particle swarm optimization is applied to structural design problems, but the method has a much wider range of possible applications. The paper's new contributions are improvements to the particle swarm optimization algorithm and conclusions and recommendations as to the utility of the algorithm, Results of numerical experiments for both continuous and discrete applications are presented in the paper. The results indicate that the particle swarm optimization algorithm does locate the constrained minimum design in continuous applications with very good precision, albeit at a much higher computational cost than that of a typical gradient based optimizer. However, the true potential of particle swarm optimization is primarily in applications with discrete and/or discontinuous functions and variables. Additionally, particle swarm optimization has the potential of efficient computation with very large numbers of concurrently operating processors.

  17. Direct on-strip analysis of size- and time-resolved aerosol impactor samples using laser induced fluorescence spectra excited at 263 and 351 nm

    International Nuclear Information System (INIS)

    Wang, Chuji; Pan, Yong-Le; James, Deryck; Wetmore, Alan E.; Redding, Brandon

    2014-01-01

    Highlights: • A dual wavelength UV-LIF spectra-rotating drum impactor (RDI) technique was developed. • The technique was demonstrated by direct on-strip analysis of size- and time-resolved LIF spectra of atmospheric aerosol particles. • More than 2000 LIF spectra of atmospheric aerosol particles collected over three weeks in Djibouti were obtained and assigned to various fluorescence clusters. • The LIF spectra showed size- and time-sensitivity behavior with a time resolution of 3.6 h. - Abstract: We report a novel atmospheric aerosol characterization technique, in which dual wavelength UV laser induced fluorescence (LIF) spectrometry marries an eight-stage rotating drum impactor (RDI), namely UV-LIF-RDI, to achieve size- and time-resolved analysis of aerosol particles on-strip. The UV-LIF-RDI technique measured LIF spectra via direct laser beam illumination onto the particles that were impacted on a RDI strip with a spatial resolution of 1.2 mm, equivalent to an averaged time resolution in the aerosol sampling of 3.6 h. Excited by a 263 nm or 351 nm laser, more than 2000 LIF spectra within a 3-week aerosol collection time period were obtained from the eight individual RDI strips that collected particles in eight different sizes ranging from 0.09 to 10 μm in Djibouti. Based on the known fluorescence database from atmospheric aerosols in the US, the LIF spectra obtained from the Djibouti aerosol samples were found to be dominated by fluorescence clusters 2, 5, and 8 (peaked at 330, 370, and 475 nm) when excited at 263 nm and by fluorescence clusters 1, 2, 5, and 6 (peaked at 390 and 460 nm) when excited at 351 nm. Size- and time-dependent variations of the fluorescence spectra revealed some size and time evolution behavior of organic and biological aerosols from the atmosphere in Djibouti. Moreover, this analytical technique could locate the possible sources and chemical compositions contributing to these fluorescence clusters. Advantages, limitations, and

  18. Direct on-strip analysis of size- and time-resolved aerosol impactor samples using laser induced fluorescence spectra excited at 263 and 351 nm

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chuji [U.S. Army Research Laboratory, Adelphi, MD 20783 (United States); Mississippi State University, Starkville, MS, 39759 (United States); Pan, Yong-Le, E-mail: yongle.pan.civ@mail.mil [U.S. Army Research Laboratory, Adelphi, MD 20783 (United States); James, Deryck; Wetmore, Alan E. [U.S. Army Research Laboratory, Adelphi, MD 20783 (United States); Redding, Brandon [Yale University, New Haven, CT 06510 (United States)

    2014-04-01

    Highlights: • A dual wavelength UV-LIF spectra-rotating drum impactor (RDI) technique was developed. • The technique was demonstrated by direct on-strip analysis of size- and time-resolved LIF spectra of atmospheric aerosol particles. • More than 2000 LIF spectra of atmospheric aerosol particles collected over three weeks in Djibouti were obtained and assigned to various fluorescence clusters. • The LIF spectra showed size- and time-sensitivity behavior with a time resolution of 3.6 h. - Abstract: We report a novel atmospheric aerosol characterization technique, in which dual wavelength UV laser induced fluorescence (LIF) spectrometry marries an eight-stage rotating drum impactor (RDI), namely UV-LIF-RDI, to achieve size- and time-resolved analysis of aerosol particles on-strip. The UV-LIF-RDI technique measured LIF spectra via direct laser beam illumination onto the particles that were impacted on a RDI strip with a spatial resolution of 1.2 mm, equivalent to an averaged time resolution in the aerosol sampling of 3.6 h. Excited by a 263 nm or 351 nm laser, more than 2000 LIF spectra within a 3-week aerosol collection time period were obtained from the eight individual RDI strips that collected particles in eight different sizes ranging from 0.09 to 10 μm in Djibouti. Based on the known fluorescence database from atmospheric aerosols in the US, the LIF spectra obtained from the Djibouti aerosol samples were found to be dominated by fluorescence clusters 2, 5, and 8 (peaked at 330, 370, and 475 nm) when excited at 263 nm and by fluorescence clusters 1, 2, 5, and 6 (peaked at 390 and 460 nm) when excited at 351 nm. Size- and time-dependent variations of the fluorescence spectra revealed some size and time evolution behavior of organic and biological aerosols from the atmosphere in Djibouti. Moreover, this analytical technique could locate the possible sources and chemical compositions contributing to these fluorescence clusters. Advantages, limitations, and

  19. Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia

    Directory of Open Access Journals (Sweden)

    J. Rissler

    2006-01-01

    Full Text Available Aerosol particle number size distributions and hygroscopic properties were measured at a pasture site in the southwestern Amazon region (Rondonia. The measurements were performed 11 September-14 November 2002 as part of LBA-SMOCC (Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate, and cover the later part of the dry season (with heavy biomass burning, a transition period, and the onset of the wet period. Particle number size distributions were measured with a DMPS (Differential Mobility Particle Sizer, 3-850nm and an APS (Aerodynamic Particle Sizer, extending the distributions up to 3.3 µm in diameter. An H-TDMA (Hygroscopic Tandem Differential Mobility Analyzer measured the hygroscopic diameter growth factors (Gf at 90% relative humidity (RH, for particles with dry diameters (dp between 20-440 nm, and at several occasions RH scans (30-90% RH were performed for 165nm particles. These data provide the most extensive characterization of Amazonian biomass burning aerosol, with respect to particle number size distributions and hygroscopic properties, presented until now. The evolution of the convective boundary layer over the course of the day causes a distinct diel variation in the aerosol physical properties, which was used to get information about the properties of the aerosol at higher altitudes. The number size distributions averaged over the three defined time periods showed three modes; a nucleation mode with geometrical median diameters (GMD of ~12 nm, an Aitken mode (GMD=61-92 nm and an accumulation mode (GMD=128-190 nm. The two larger modes were shifted towards larger GMD with increasing influence from biomass burning. The hygroscopic growth at 90% RH revealed a somewhat external mixture with two groups of particles; here denoted nearly hydrophobic (Gf~1.09 for 100 nm particles and moderately hygroscopic (Gf~1.26. While the hygroscopic growth factors were surprisingly similar over the

  20. Laser induced changes of As.sub.50./sub.Se.sub.50./sub. nanolayers studied by synchrotron radiation photoelectron spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Kondrat, O.; Popovich, N.; Holomb, R.; Mitsa, V.; Lyamayev, V.; Tsud, N.; Cháb, Vladimír; Matolín, V.; Prince, K. C.

    2012-01-01

    Roč. 520, č. 24 (2012), s. 7224-7229 ISSN 0040-6090 R&D Projects: GA MŠk(CZ) LC06058 Institutional support: RVO:68378271 Keywords : chalcogenide glass * photostructural changes * photoelectron spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.604, year: 2012

  1. Music of elementary particles

    International Nuclear Information System (INIS)

    Sternheimer, J.

    1983-01-01

    This Note offers a new point of view on particle masses. It is shown that they are distributed following a musical scale, the chromatic tempered scale -for stable particles- subdivided into microintervals including unstable particles. A theoretical explanation, based on causality, allows one also to calculate their global distribution along the mass scale, in agreement with experiment, and indicating the existence of ''musical'' laws in the vibratory organisation of matter [fr

  2. Low energy particle composition

    International Nuclear Information System (INIS)

    Gloeckler, G.

    1975-01-01

    More than 50 papers presented at this Conference dealt with the composition of low energy particles. The topics can be divided roughly into two broad categories. The first is the study of the energy spectra and composition of the steady or 'quiet-time' particle flux, whose origin is at this time unknown. The second category includes the study of particles and photons which are associated with solar flares or active regions on the sun. (orig.) [de

  3. Music of elementary particles

    Energy Technology Data Exchange (ETDEWEB)

    Sternheimer, J.

    1983-12-12

    This note offers a new point of view on particle masses. It is shown that they are distributed following a musical scale, the chromatic tempered scale -for stable particles- subdivided into microintervals including unstable particles. A theoretical explanation, based on causality, allows one also to calculate their global distribution along the mass scale, in agreement with experiment, and indicating the existence of ''musical'' laws in the vibratory organisation of matter.

  4. Review of particle properties

    International Nuclear Information System (INIS)

    Bricman, C.; Dionisi, C.; Hemingway, R.J.; Mazzucato, M.; Montanet, L.; Barash-Schmidt, N.; Crawford, R.C.; Roos, M.; Barbaro-Galtieri, A.; Horne, C.P.; Kelly, R.L.; Losty, M.J.; Rittenberg, A.; Trippe, T.G.; Yost, G.P.; Armstrong, B.

    1978-01-01

    This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Rev. Mod. Phys. 48 (1976) No. 2, Part II; and Supplement, Phys. Lett. 68B (1977) 1]. Data are evaluated, listed, averaged, and summarized in tables. Numerous tables, figures, and formulae of interest to particle physicists are also included. A data booklet is available. (Auth.)

  5. Condensed elementary particle matter

    International Nuclear Information System (INIS)

    Kajantie, K.

    1996-01-01

    Quark matter is a special case of condensed elementary particle matter, matter governed by the laws of particle physics. The talk discusses how far one can get in the study of particle matter by reducing the problem to computations based on the action. As an example the computation of the phase diagram of electroweak matter is presented. It is quite possible that ultimately an antireductionist attitude will prevail: experiments will reveal unpredicted phenomena not obviously reducible to the study of the action. (orig.)

  6. Mobility and height detection of particle labels in an optical evanescent wave biosensor with single-label resolution

    Energy Technology Data Exchange (ETDEWEB)

    Van Ommering, Kim; Koets, Marjo; Schleipen, Jean J H B; Prins, Menno W J [Philips Research Laboratories, 5656 AE Eindhoven (Netherlands); Somers, Philip A; Van IJzendoorn, Leo J, E-mail: menno.prins@philips.co [Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands)

    2010-04-21

    Particle labels are used in biosensors to detect the presence and concentration of analyte molecules. In this paper we demonstrate an optical technique to measure the mobility and height of bound particle labels on a biosensor surface with single-label resolution. The technique is based on the detection of the particle-induced light scattering in an optical evanescent field. We show that the thermal particle motion in the optical evanescent field leads to intensity fluctuations that can accurately be detected. The technique is demonstrated using 290 bp (99 nm) DNA as an analyte and using polystyrene particles and magnetic particles with diameters between 500 and 1000 nm as labels. The particle intensity histograms show that quantitative height measurements are obtained for particles with uniform optical properties, and the intensity versus position plots reflect the analyte-antibody orientation and the analyte flexibility. The novel optical detection technique will lead to biosensors with very high sensitivity and specificity.

  7. Noble metal (NM) behavior during simulated HLLW vitrification in induction melter with cold crucible

    International Nuclear Information System (INIS)

    Demin, A.V.; Matyunin, Y.I.; Fedorova, M.I.

    1995-01-01

    The investigation of noble metal (Ru, Rh, Pd) properties in, glass melts are connected with their specific behaviors during HLLW vitrification. Ruthenium, rhodium and palladium volatilities and heterogeneous platinoid phases forming on melts are investigated in reasonable details conformably to Joule's heating ceramic melters. The vitrification conditions in melters with induction heating of melts are differ from the vitrification ones in ceramic melters on some numbers of parameters (the availability of significant temperature gradients and convection flows in melts, short time of molten mass updating in melter and probability of definite interaction between high-frequency field and melt inhomogeneities). The results of simulated HLLW solidification modelling of the vitrification process in induction melter with cold crucible to produce phosphate and boron-silicate materials are presented. The properties of received glasses and behavior of platinoids are shown to have analogies and distinctions in comparison with compounds, synthesized in ceramic melter. The structures of dispersed particles of NM heterogeneous phases forming in glass melts prepared in induction melter with cold crucible are identified. The results of investigations show, that the marked distinctions between two processes can influence (in definite degree) as on property of synthesized materials, as on behavior of platinoid during vitrifications

  8. Development of Radiation-hard Bandgap Reference and Temperature Sensor in CMOS 130 nm Technology

    CERN Document Server

    Kuczynska, Marika; Bugiel, Szymon; Firlej, Miroslaw; Fiutowski, Tomasz; Idzik, Marek; Michelis, Stefano; Moron, Jakub; Przyborowski, Dominik; Swientek, Krzysztof

    2015-01-01

    A stable reference voltage (or current) source is a standard component of today's microelectronics systems. In particle physics experiments such reference is needed in spite of harsh ionizing radiation conditions, i.e. doses exceeding 100 Mrads and fluences above 1e15 n/cm2. After such radiation load a bandgap reference using standard p-n junction of bipolar transistor does not work properly. Instead of using standard p-n junctions, two enclosed layout transistor (ELTMOS) structures are used to create radiation-hard diodes: the ELT bulk diode and the diode obtained using the ELTMOS as dynamic threshold transistor (DTMOS). In this paper we have described several sub-1V references based on ELTMOS bulk diode and DTMOS based diode, using CMOS 130 nm process. Voltage references the structures with additional PTAT (Proportional To Absolute Temperature) output for temperature measurements were also designed. We present and compare post-layout simulations of the developed bandgap references and temperature sensors, w...

  9. A 130 nm ASIC prototype for the NA62 Gigatracker readout

    CERN Document Server

    Dellacasa, G; Wheadon, R; Mazza, G; Rivetti, A; Marchetto, F; Garbolino, S

    2011-01-01

    One of the most challenging detectors of the NA62 experiment is the silicon tracker, called Gigatracker. It consists of three hybrid silicon pixel stations, each one covering an area of 27 mm x 60 mm. While the maximum pixel size is fairly large, 300 mu m x 300 mu m the system has to sustain a very high particle rate, 1.5 MHz/mm(2), which corresponds to 800 MHz for each station. To obtain an efficient tracking with such a high rate the required track timing resolution is 150 ps (rms). Therefore the front-end ASIC should provide for each pixel a 200 Ps time measurement capability, thus leading to the requirement of time walk compensation and very compact TDCs. Moreover, Single Event Upset protection has to be implemented in order to protect the digital circuitry. An ASIC prototype has been realized in CMOS 130 nm technology, containing three pixel columns. The chip performs the time walk compensation by a Constant Fraction Discriminator circuit, while the time measurement is performed by a Time to Amplitude Co...

  10. A 130 nm ASIC prototype for the NA62 Gigatracker readout

    Energy Technology Data Exchange (ETDEWEB)

    Dellacasa, G., E-mail: gdellaca@to.infn.it [I.N.F.N. sez. Torino, via Giuria 1, 10125 Torino (Italy); Garbolino, S. [Universita degli Studi di Torino, Dip. Fisica Sperimentale, via Giuria 1, 10125 Torino (Italy); Marchetto, F. [I.N.F.N. sez. Torino, via Giuria 1, 10125 Torino (Italy); Martoiu, S. [I.N.F.N. sez. Torino, via Giuria 1, 10125 Torino (Italy); CERN CH-1211, Geneve 23 (Switzerland); Mazza, G.; Rivetti, A.; Wheadon, R. [I.N.F.N. sez. Torino, via Giuria 1, 10125 Torino (Italy)

    2011-09-11

    One of the most challenging detectors of the NA62 experiment is the silicon tracker, called Gigatracker. It consists of three hybrid silicon pixel stations, each one covering an area of 27 mmx60 mm. While the maximum pixel size is fairly large, 300{mu}mx300{mu}m the system has to sustain a very high particle rate, 1.5 MHz/mm{sup 2}, which corresponds to 800 MHz for each station. To obtain an efficient tracking with such a high rate the required track timing resolution is 150 ps (rms). Therefore the front-end ASIC should provide for each pixel a 200 ps time measurement capability, thus leading to the requirement of time walk compensation and very compact TDCs. Moreover, Single Event Upset protection has to be implemented in order to protect the digital circuitry. An ASIC prototype has been realized in CMOS 130 nm technology, containing three pixel columns. The chip performs the time walk compensation by a Constant Fraction Discriminator circuit, while the time measurement is performed by a Time to Amplitude Converter based TDC, both of them implemented on each pixel cell. The End of Column circuit containing only digital logic is responsible for the data readout from the pixel cell. The whole chip works with a system clock of 160 MHz and the digital logic is SEU protected by the use of Hamming codes. The detailed architecture of the ASIC prototype and test results are presented.

  11. A 65 nm CMOS analog processor with zero dead time for future pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gaioni, L., E-mail: luigi.gaioni@unibg.it [Università di Bergamo, I-24044 Dalmine (Italy); INFN, Sezione di Pavia, I-27100 Pavia (Italy); Braga, D.; Christian, D.C.; Deptuch, G.; Fahim, F. [Fermi National Accelerator Laboratory, Batavia IL (United States); Nodari, B. [Università di Bergamo, I-24044 Dalmine (Italy); INFN, Sezione di Pavia, I-27100 Pavia (Italy); Centre National de Recherche Scientifique, APC/IN2P3, Paris (France); Ratti, L. [Università di Pavia, I-27100 Pavia (Italy); INFN, Sezione di Pavia, I-27100 Pavia (Italy); Re, V. [Università di Bergamo, I-24044 Dalmine (Italy); INFN, Sezione di Pavia, I-27100 Pavia (Italy); Zimmerman, T. [Fermi National Accelerator Laboratory, Batavia IL (United States)

    2017-02-11

    Next generation pixel chips at the High-Luminosity (HL) LHC will be exposed to extremely high levels of radiation and particle rates. In the so-called Phase II upgrade, ATLAS and CMS will need a completely new tracker detector, complying with the very demanding operating conditions and the delivered luminosity (up to 5×10{sup 34} cm{sup −2} s{sup −1} in the next decade). This work is concerned with the design of a synchronous analog processor with zero dead time developed in a 65 nm CMOS technology, conceived for pixel detectors at the HL-LHC experiment upgrades. It includes a low noise, fast charge sensitive amplifier featuring a detector leakage compensation circuit, and a compact, single ended comparator that guarantees very good performance in terms of channel-to-channel dispersion of threshold without needing any pixel-level trimming. A flash ADC is exploited for digital conversion immediately after the charge amplifier. A thorough discussion on the design of the charge amplifier and the comparator is provided along with an exhaustive set of simulation results.

  12. Leaping shampoo glides on a 500-nm-thick lubricating air layer

    Science.gov (United States)

    Li, Erqiang; Lee, Sanghyun; Marston, Jeremy; Bonito, Andrea; Thoroddsen, Sigurdur

    2013-11-01

    When a stream of shampoo is fed onto a pool in one's hand, a jet can leap sideways or rebound from the liquid surface in an intriguing phenomenon known as the Kaye effect. Earlier studies have debated whether non-Newtonian effects are the underlying cause of this phenomenon, making the jet glide on top of a shear-thinning liquid layer, or whether an entrained air layer is responsible. Herein we show unambiguously that the jet slides on a lubricating air layer [Lee et al., Phys. Rev. E 87, 061001 (2013)]. We identify this layer by looking through the pool liquid and observing its rupture into fine micro-bubbles. The resulting micro-bubble sizes suggest that the thickness of this air layer is around 500 nm. This thickness estimate is also supported by the tangential deceleration of the jet during the rebounding, with the shear stress within the thin air layer sufficient for the observed deceleration. Particle tracking within the jet shows uniform velocity, with no pronounced shear, which would be required for shear-thinning effects. The role of the surfactant may primarily be to stabilize the air film.

  13. Particle correlations at ALICE

    Energy Technology Data Exchange (ETDEWEB)

    Erazmus, B.; Lednicky, R.; Lyuboshitz, V.; Martin, L.; Mikhailov, K.; Pluta, J.; Sinyukov, Yu.; Stavinsky, A.; Werner, K

    1998-12-31

    The ability of the ALICE detector for determination of the space-time characteristics of particle production in heavy-ion collisions at LHC from measurements of the correlation functions of identical and non-identical particles at small relative velocities is discussed. The possibility to use the correlations of non-identical particles for a direct determination of the delays in emission of various particle species at time scales as small as 10{sup -23} s is demonstrated. The influence of the multi-boson effects on pion multiplicities, single-pion spectra and two-pion correlation functions is discussed. (author) 63 refs.

  14. Particle Correlations at LEP

    CERN Document Server

    Kress, Thomas

    2002-01-01

    Particle correlations are extensively studied to obtain information about the dynamics of hadron production. From 1989 to 2000 the four LEP collaborations recorded more than 16 million hadronic Z0 decays and several thousand W+W- events. In Z0 decays, two-particle correlations were analysed in detail to study Bose-Einstein and Fermi-Dirac correlations for various particle species. In fully-hadronic W+W- decays, particle correlations were used to study whether the two W bosons decay independently. A review of selected results is presented.

  15. Particle Image Velocimetry

    DEFF Research Database (Denmark)

    Zhang, Chen; Vasilevskis, Sandijs; Kozlowski, Bartosz

    Particle image velocimetry (PIV) is a non-intrusive, whole filed optical method providing instantaneous velocity information in fluids. The flow is seeded with tracer particles. The particles are illuminated in the target area with a light sheet at least twice within a short time interval....... The camera images the target area and captures each light pulse in separate image frames. The displacement of the particle between the light pulses can be used to determine the velocity vectors. This guideline introduces the principle of the PIV system and the system configuration. The measurement procedure...

  16. Review of particle properties

    International Nuclear Information System (INIS)

    Hikasa, K.; Hagiwara, K.; Kawabata, S.; Barnett, R.M.; Groom, D.E.; Trippe, T.G.; Wohl, C.G.; Yost, G.P.; Armstrong, B. Technical Associate; Wagman, G.S. Technical Associate; Stone, J.; Porter, F.C.; Morrison, R.J.; Cutkosky, R.E.; Montanet, L.; Gieselmann, K. Technical Associate; Aguilar-Benitez, M.; Caso, C.; Crawford, R.L.; Roos, M.; Toernqvist, N.A.; Hayes, K.G.; Hoehler, G.; Manley, D.M.

    1992-01-01

    In this Review, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, the top quark, heavy neutrinos, monopoles, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. A booklet is available containing the Summary Tables and abbreviated versions of some other sections of this full Review

  17. Elementary particle theory

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1984-12-01

    The present state of the art in elementary particle theory is reviewed. Topics include quantum electrodynamics, weak interactions, electroweak unification, quantum chromodynamics, and grand unified theories. 113 references

  18. Particle physics experiments 1983

    International Nuclear Information System (INIS)

    Stuart, G.W.

    1983-01-01

    The report describes work carried out in 1983 on experiments approved by the Particle Physics Experiments Selection Panel. The contents consist of unedited contributions from each experiment. (author)

  19. Particle Physics & Astrophysics (PPA)

    Data.gov (United States)

    Federal Laboratory Consortium — Scientists at SLAC's Particle Physics and Astrophysics develop and utilize unique instruments from underground to outer space to explore the ultimate laws of nature...

  20. Improved identification of primary biological aerosol particles using single-particle mass spectrometry

    Directory of Open Access Journals (Sweden)

    M. A. Zawadowicz

    2017-06-01

    Full Text Available Measurements of primary biological aerosol particles (PBAP, especially at altitudes relevant to cloud formation, are scarce. Single-particle mass spectrometry (SPMS has been used to probe aerosol chemical composition from ground and aircraft for over 20 years. Here we develop a method for identifying bioaerosols (PBAP and particles containing fragments of PBAP as part of an internal mixture using SPMS. We show that identification of bioaerosol using SPMS is complicated because phosphorus-bearing mineral dust and phosphorus-rich combustion by-products such as fly ash produce mass spectra with peaks similar to those typically used as markers for bioaerosol. We have developed a methodology to differentiate and identify bioaerosol using machine learning statistical techniques applied to mass spectra of known particle types. This improved method provides far fewer false positives compared to approaches reported in the literature. The new method was then applied to two sets of ambient data collected at Storm Peak Laboratory and a forested site in Central Valley, California to show that 0.04–2 % of particles in the 200–3000 nm aerodynamic diameter range were identified as bioaerosol. In addition, 36–56 % of particles identified as biological also contained spectral features consistent with mineral dust, suggesting internal dust–biological mixtures.

  1. Microbes make average 2 nanometer diameter crystalline UO2 particles.

    Science.gov (United States)

    Suzuki, Y.; Kelly, S. D.; Kemner, K. M.; Banfield, J. F.

    2001-12-01

    It is well known that phylogenetically diverse groups of microorganisms are capable of catalyzing the reduction of highly soluble U(VI) to highly insoluble U(IV), which rapidly precipitates as uraninite (UO2). Because biological uraninite is highly insoluble, microbial uranyl reduction is being intensively studied as the basis for a cost-effective in-situ bioremediation strategy. Previous studies have described UO2 biomineralization products as amorphous or poorly crystalline. The objective of this study is to characterize the nanocrystalline uraninite in detail in order to determine the particle size, crystallinity, and size-related structural characteristics, and to examine the implications of these for reoxidation and transport. In this study, we obtained U-contaminated sediment and water from an inactive U mine and incubated them anaerobically with nutrients to stimulate reductive precipitation of UO2 by indigenous anaerobic bacteria, mainly Gram-positive spore-forming Desulfosporosinus and Clostridium spp. as revealed by RNA-based phylogenetic analysis. Desulfosporosinus sp. was isolated from the sediment and UO2 was precipitated by this isolate from a simple solution that contains only U and electron donors. We characterized UO2 formed in both of the experiments by high resolution-TEM (HRTEM) and X-ray absorption fine structure analysis (XAFS). The results from HRTEM showed that both the pure and the mixed cultures of microorganisms precipitated around 1.5 - 3 nm crystalline UO2 particles. Some particles as small as around 1 nm could be imaged. Rare particles around 10 nm in diameter were also present. Particles adhere to cells and form colloidal aggregates with low fractal dimension. In some cases, coarsening by oriented attachment on \\{111\\} is evident. Our preliminary results from XAFS for the incubated U-contaminated sample also indicated an average diameter of UO2 of 2 nm. In nanoparticles, the U-U distance obtained by XAFS was 0.373 nm, 0.012 nm

  2. Nucleation of Magnetization Reversal in Individual Nanosized Particles and Wires

    Science.gov (United States)

    Wernsdorfer, W.

    1997-03-01

    Low temperatures magnetization measurements of individual ferromagnetic particles and wires are presented. The detector was a Nb micro-bridge-DC-SQUID, elaborated using electron-beam lithography. We studied particles fabricated by electron beam lithography. They had an elliptic contour with axes between 50 and 1000 nm and a thickness between 5 and 50 nm and were made of Ni, Co, Fe (W. Wernsdorfer et al., J. Magn. Magn. Mat., 145, 33 (1995) and 151, 38 (1995), and Phys. Rev. B, 53, 3341 (1996).). Furthermore, we studied Ni and Co wires (cylinders) with diameters ranging from 40 nm to 100 nm and lengths up to 5000 nm (W. Wernsdorfer et al., Phys. Rev. Lett., 77, 1873 (1996)). They were produced by the technique of electrodeposition in nanoporous polycarbonate membranes (J. Meier, B. Doudin and J.-Ph. Ansermet, J. Appl. Phys, 79, 6010 (1996).). We studied nanoparticles and filled carbon nanotubes synthesized by arc-discharge, with dimensions between 10 and 500 nm. These particles are single crystalline and the surface roughness is about two atomic layers (C. Guerret-Pi=E9court, Y. Le Bouar, A. Loiseau and H. Pascard, Nature, 372, 761 (1994).). Finally, we studied single crystalline particles elaborated by colloidal self assemblies (M. P. Pileni et al., submitted.). The angular dependence of the magnetization reversal could be explained approximately by simple classical micromagnetic concepts: uniform rotation and curling. However, our measurement evidenced nucleation and propagation of domain walls except for the smallest particles of about 20 nm. The switching field distributions as a function of temperature and field sweeping rate and the probabilities of switching showed that the magnetization reversal was thermally activated. These measurements allowed us to estimate the "activation volume" which triggered the magnetization reversal. Our measurements showed for the first time that the magnetization reversal of a ferromagnetic nanoparticle of good quality can be

  3. Novel EUV photoresist for sub-7nm node (Conference Presentation)

    Science.gov (United States)

    Furukawa, Tsuyoshi; Naruoka, Takehiko; Nakagawa, Hisashi; Miyata, Hiromu; Shiratani, Motohiro; Hori, Masafumi; Dei, Satoshi; Ayothi, Ramakrishnan; Hishiro, Yoshi; Nagai, Tomoki

    2017-04-01

    Extreme ultraviolet (EUV) lithography has been recognized as a promising candidate for the manufacturing of semiconductor devices as LS and CH pattern for 7nm node and beyond. EUV lithography is ready for high volume manufacturing stage. For the high volume manufacturing of semiconductor devices, significant improvement of sensitivity and line edge roughness (LWR) and Local CD Uniformity (LCDU) is required for EUV resist. It is well-known that the key challenge for EUV resist is the simultaneous requirement of ultrahigh resolution (R), low line edge roughness (L) and high sensitivity (S). Especially high sensitivity and good roughness is important for EUV lithography high volume manufacturing. We are trying to improve sensitivity and LWR/LCDU from many directions. From material side, we found that both sensitivity and LWR/LCDU are simultaneously improved by controlling acid diffusion length and efficiency of acid generation using novel resin and PAG. And optimizing EUV integration is one of the good solution to improve sensitivity and LWR/LCDU. We are challenging to develop new multi-layer materials to improve sensitivity and LWR/LCDU. Our new multi-layer materials are designed for best performance in EUV lithography system. From process side, we found that sensitivity was substantially improved maintaining LWR applying novel type of chemical amplified resist (CAR) and process. EUV lithography evaluation results obtained for new CAR EUV interference lithography. And also metal containing resist is one possibility to break through sensitivity and LWR trade off. In this paper, we will report the recent progress of sensitivity and LWR/LCDU improvement of JSR novel EUV resist and process.

  4. Simulation of 50-nm Gate Graphene Nanoribbon Transistors

    Directory of Open Access Journals (Sweden)

    Cedric Nanmeni Bondja

    2016-01-01

    Full Text Available An approach to simulate the steady-state and small-signal behavior of GNR MOSFETs (graphene nanoribbon metal-semiconductor-oxide field-effect transistor is presented. GNR material parameters and a method to account for the density of states of one-dimensional systems like GNRs are implemented in a commercial device simulator. This modified tool is used to calculate the current-voltage characteristics as well the cutoff frequency fT and the maximum frequency of oscillation fmax of GNR MOSFETs. Exemplarily, we consider 50-nm gate GNR MOSFETs with N = 7 armchair GNR channels and examine two transistor configurations. The first configuration is a simplified MOSFET structure with a single GNR channel as usually studied by other groups. Furthermore, and for the first time in the literature, we study in detail a transistor structure with multiple parallel GNR channels and interribbon gates. It is shown that the calculated fT of GNR MOSFETs is significantly lower than that of GFETs (FET with gapless large-area graphene channel with comparable gate length due to the mobility degradation in GNRs. On the other hand, GNR MOSFETs show much higher fmax compared to experimental GFETs due the semiconducting nature of the GNR channels and the resulting better saturation of the drain current. Finally, it is shown that the gate control in FETs with multiple parallel GNR channels is improved while the cutoff frequency is degraded compared to single-channel GNR MOSFETs due to parasitic capacitances of the interribbon gates.

  5. Elemental fractionation in 785 nm picosecond and femtosecond laser ablation inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shaheen, M.E., E-mail: mshaheen73@science.tanta.edu.eg [Department of Physics, Faculty of Sciences, Tanta University, Tanta (Egypt); Gagnon, J.E.; Fryer, B.J. [Great Lakes Institute for Environmental Research (GLIER), University of Windsor, Windsor, Ontario N9B 3P4 (Canada); Department of Earth and Environmental Sciences, University of Windsor, Windsor, Ontario N9B 3P4 (Canada)

    2015-05-01

    Elemental fractionation and ICP-MS signal response were investigated for two different pulse width laser beams originating from the same laser system. Femtosecond and picosecond laser beams at pulse widths of 130 fs and 110 ps, respectively, and wavelength of 785 nm were used to ablate NIST 610 synthetic glass and SRM 1107 Naval Brass B at the same spot for 800 to 1000 laser pulses at different repetition rates (5 to 50 Hz). Elemental fractionation was found to depend on repetition rate and showed a trend with femtosecond laser ablation that is opposite to that observed in picosecond laser ablation for most measured isotopes. ICP-MS signal intensity was higher in femtosecond than picosecond LA-ICP-MS in both NIST 610 and naval brass when ablation was conducted under the same fluence and repetition rate. The differences in signal intensity were partly related to differences in particle size distribution between particles generated by femtosecond and picosecond laser pulses and the consequent differences in transport and ionization efficiencies. The main reason for the higher signal intensity resulting from femtosecond laser pulses was related to the larger crater sizes compared to those created during picosecond laser ablation. Elemental ratios measured using {sup 66}Zn/{sup 63}Cu, {sup 208}Pb/{sup 238}U, {sup 232}Th/{sup 238}U, {sup 66}Zn/{sup 232}Th and {sup 66}Zn/{sup 208}Pb were found to change with the number of laser pulses with data points being more scattered in picosecond than femtosecond laser pulses. Reproducibility of replicate measurements of signal intensities, fractionation and elemental ratios was better for fs-LA-ICP-MS (RSD ~ 3 to 6%) than ps-LA-ICP-MS (RSD ~ 7 to 11%). - Highlights: • Fractionation and ICP-MS signal response were investigated for two different pulse widths using NIST 610 and Naval Brass. • Dependence of fractionation indices on repetition rate and pulse width. • Higher ablation rate was observed in picosecond compared to

  6. Elemental fractionation in 785 nm picosecond and femtosecond laser ablation inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Shaheen, M.E.; Gagnon, J.E.; Fryer, B.J.

    2015-01-01

    Elemental fractionation and ICP-MS signal response were investigated for two different pulse width laser beams originating from the same laser system. Femtosecond and picosecond laser beams at pulse widths of 130 fs and 110 ps, respectively, and wavelength of 785 nm were used to ablate NIST 610 synthetic glass and SRM 1107 Naval Brass B at the same spot for 800 to 1000 laser pulses at different repetition rates (5 to 50 Hz). Elemental fractionation was found to depend on repetition rate and showed a trend with femtosecond laser ablation that is opposite to that observed in picosecond laser ablation for most measured isotopes. ICP-MS signal intensity was higher in femtosecond than picosecond LA-ICP-MS in both NIST 610 and naval brass when ablation was conducted under the same fluence and repetition rate. The differences in signal intensity were partly related to differences in particle size distribution between particles generated by femtosecond and picosecond laser pulses and the consequent differences in transport and ionization efficiencies. The main reason for the higher signal intensity resulting from femtosecond laser pulses was related to the larger crater sizes compared to those created during picosecond laser ablation. Elemental ratios measured using 66 Zn/ 63 Cu, 208 Pb/ 238 U, 232 Th/ 238 U, 66 Zn/ 232 Th and 66 Zn/ 208 Pb were found to change with the number of laser pulses with data points being more scattered in picosecond than femtosecond laser pulses. Reproducibility of replicate measurements of signal intensities, fractionation and elemental ratios was better for fs-LA-ICP-MS (RSD ~ 3 to 6%) than ps-LA-ICP-MS (RSD ~ 7 to 11%). - Highlights: • Fractionation and ICP-MS signal response were investigated for two different pulse widths using NIST 610 and Naval Brass. • Dependence of fractionation indices on repetition rate and pulse width. • Higher ablation rate was observed in picosecond compared to femtosecond laser ablation of NIST 610 and Brass

  7. Toxicogenomic analysis of the particle dose- and size-response relationship of silica particles-induced toxicity in mice

    International Nuclear Information System (INIS)

    Lu Xiaoyan; Jin Tingting; Jin Yachao; Wu Leihong; Hu Bin; Tian Yu; Fan Xiaohui

    2013-01-01

    This study investigated the relationship between particle size and toxicity of silica particles (SP) with diameters of 30, 70, and 300 nm, which is essential to the safe design and application of SP. Data obtained from histopathological examinations suggested that SP of these sizes can all induce acute inflammation in the liver. In vivo imaging showed that intravenously administrated SP are mainly present in the liver, spleen and intestinal tract. Interestingly, in gene expression analysis, the cellular response pathways activated in the liver are predominantly conserved independently of particle dose when the same size SP are administered or are conserved independently of particle size, surface area and particle number when nano- or submicro-sized SP are administered at their toxic doses. Meanwhile, integrated analysis of transcriptomics, previous metabonomics and conventional toxicological results support the view that SP can result in inflammatory and oxidative stress, generate mitochondrial dysfunction, and eventually cause hepatocyte necrosis by neutrophil-mediated liver injury. (paper)

  8. Airborne measurements of nucleation mode particles I: coastal nucleation and growth rates

    Directory of Open Access Journals (Sweden)

    C. D. O'Dowd

    2007-01-01

    Full Text Available A light aircraft was equipped with a bank of Condensation Particle Counters (CPCs (50% cut from 3–5.4–9.6 nm and a nano-Scanning Mobility Particle Sizer (nSMPS and deployed along the west coast of Ireland, in the vicinity of Mace Head. The objective of the exercise was to provide high resolution micro-physical measurements of the coastal nucleation mode in order to map the spatial extent of new particle production regions and to evaluate the evolution, and associated growth rates of the coastal nucleation-mode aerosol plume. Results indicate that coastal new particle production is occurring over most areas along the land-sea interface with peak concentrations at the coastal plume-head in excess of 106 cm−3. Pseudo-Lagrangian studies of the coastal plume evolution illustrated significant growth of new particles to sizes in excess of 8 nm approximately 10 km downwind of the source region. Close to the plume head (<1 km growth rates can be as high as 123–171 nm h−1, decreasing gradually to 53–72 nm h−1 at 3 km. Further along the plume, at distances up to 10 km, the growth rates are calculated to be 17–32 nm h−1. Growth rates of this magnitude suggest that after a couple of hours, coastal nucleation mode particles can reach significant sizes where they can contribution to the regional aerosol loading.

  9. Aerosol number size distribution and new particle formation at a rural/coastal site in Pearl River Delta (PRD) of China

    Science.gov (United States)

    Liu, Shang; Hu, Min; Wu, Zhijun; Wehner, Birgit; Wiedensohler, Alfred; Cheng, Yafang

    Continuous measurements of aerosol number size distribution in the range of 3 nm-10 μm were performed in Pearl River Delta (PRD), China. These measurements were made during the period of 3 October to 5 November in 2004 at rural/coastal site, Xinken (22°37'N, 113°35'E, 6 m above sea level), in the south suburb of Guangzhou City (22°37'N, 113°35'E, 6 m above sea level), using a Twin Differential Mobility Particle Sizer (TDMPS) combined with an Aerodynamic Particle Sizer (APS). The aerosol particles at Xinken were divided into four groups according to the observation results: nucleation mode particles (3-30 nm), Aitken mode particles (30-130 nm), accumulation mode particles (130-1000 nm) and coarse mode particles (1-10 μm). Concentrations of nucleation mode, Aitken mode and accumulation mode particles were observed in the same order of magnitude (about 10,000 cm -3), among which the concentration of Aitken mode particle was the highest. The Aitken mode particles usually had two peaks: the morning peak may be caused by the land-sea circulation, which is proven to be important for transporting aged aerosols back to the sampling site, while the noon peak was ascribed to the condensational growth of new particles. New particle formation events were found on 7 days of 27 days, the new particle growth rates ranged from 2.2 to 19.8 nm h -1 and the formation rates ranged from 0.5 to 5.2 cm -3 s -1, both of them were in the range of typical observed formation rates (0.01-10 cm -3 s -1) and typical particle growth rates (1-20 nm h -1). The sustained growth of the new particles for several hours under steady northeast wind indicated that the new particle formation events may occur in a large homogeneous air mass.

  10. Design and Fabrication of 850 and 980 nm Vertical Cavity Surface Emitting Laser

    National Research Council Canada - National Science Library

    Das, N

    2004-01-01

    .... VCSELs on GaAs substrates were grown by the molecular beam epitaxy technique. In this report we present detailed procedures to design and fabricate 850-nm top-emitting and 980-nm bottom-emitting VCSELs...

  11. Particle Swarm Optimisation with Spatial Particle Extension

    DEFF Research Database (Denmark)

    Krink, Thiemo; Vesterstrøm, Jakob Svaneborg; Riget, Jacques

    2002-01-01

    In this paper, we introduce spatial extension to particles in the PSO model in order to overcome premature convergence in iterative optimisation. The standard PSO and the new model (SEPSO) are compared w.r.t. performance on well-studied benchmark problems. We show that the SEPSO indeed managed...

  12. Violation of Particle Anti-particle Symmetry

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    Symmetry is a fundamental concept which can be found in the whole range of human activities e. g. from arts to science. The beauty of a statues is often related to its symmetric form. In physics, all the laws are related to some sort of symmetry. Equally important is a small breakdown ofsymmetry. Even for the case of a statue, its beauty might be enhanced by introducing small distortions. In this course, we investigate the role symmetry in the world of elementary particles. Some symmetries found there are very similar to those which can be seen in our daily life, while others are more exotic and related to the quantum nature of the elementary particles. Our particular focus ismade on symmetry and its violation between the matter and anti-matter, known as CP violation. It is experimentally well established that particleand anti-particle behave a tiny bit differently in the world of elementary particles. We discuss how this would be explained and how we can extendour knowledge. Evolution of our universe is stro...

  13. Characteristics of Fine Particles in an Urban Atmosphere—Relationships with Meteorological Parameters and Trace Gases

    Science.gov (United States)

    Zhang, Tianhao; Zhu, Zhongmin; Gong, Wei; Xiang, Hao; Fang, Ruimin

    2016-01-01

    Atmospheric fine particles (diameter industrial emissions. To reveal the characteristics of fine particles in an industrial city of a developing country, two-year measurements of particle number size distribution (15.1 nm–661 nm), meteorological parameters, and trace gases were made in the city of Wuhan located in central China from June 2012 to May 2014. The annual average particle number concentrations in the nucleation mode (15.1 nm–30 nm), Aitken mode (30 nm–100 nm), and accumulation mode (100 nm–661 nm) reached 4923 cm−3, 12193 cm−3 and 4801 cm−3, respectively. Based on Pearson coefficients between particle number concentrations and meteorological parameters, precipitation and temperature both had significantly negative relationships with particle number concentrations, whereas atmospheric pressure was positively correlated with the particle number concentrations. The diurnal variation of number concentration in nucleation mode particles correlated closely with photochemical processes in all four seasons. At the same time, distinct growth of particles from nucleation mode to Aitken mode was only found in spring, summer, and autumn. The two peaks of Aitken mode and accumulation mode particles in morning and evening corresponded obviously to traffic exhaust emissions peaks. A phenomenon of “repeated, short-lived” nucleation events have been created to explain the durability of high particle concentrations, which was instigated by exogenous pollutants, during winter in a case analysis of Wuhan. Measurements of hourly trace gases and segmental meteorological factors were applied as proxies for complex chemical reactions and dense industrial activities. The results of this study offer reasonable estimations of particle impacts and provide references for emissions control strategies in industrial cities of developing countries. PMID:27517948

  14. Effect of Particle Size and Operating Conditions on Pt3Co PEMFC Cathode Catalyst Durability

    Directory of Open Access Journals (Sweden)

    Mallika Gummalla

    2015-05-01

    Full Text Available The initial performance and decay trends of polymer electrolyte membrane fuel cells (PEMFC cathodes with Pt3Co catalysts of three mean particle sizes (4.9 nm, 8.1 nm, and 14.8 nm with identical Pt loadings are compared. Even though the cathode based on 4.9 nm catalyst exhibited the highest initial electrochemical surface area (ECA and mass activity, the cathode based on 8.1 nm catalyst showed better initial performance at high currents. Owing to the low mass activity of the large particles, the initial performance of the 14.8 nm Pt3Co-based electrode was the lowest. The performance decay rate of the electrodes with the smallest Pt3Co particle size was the highest and that of the largest Pt3Co particle size was lowest. Interestingly, with increasing number of decay cycles (0.6 to 1.0 V, 50 mV/s, the relative improvement in performance of the cathode based on 8.1 nm Pt3Co over the 4.9 nm Pt3Co increased, owing to better stability of the 8.1 nm catalyst. The electron microprobe analysis (EMPA of the decayed membrane-electrode assembly (MEA showed that the amount of Co in the membrane was lower for the larger particles, and the platinum loss into the membrane also decreased with increasing particle size. This suggests that the higher initial performance at high currents with 8.1 nm Pt3Co could be due to lower contamination of the ionomer in the electrode. Furthermore, lower loss of Co from the catalyst with increased particle size could be one of the factors contributing to the stability of ECA and mass activity of electrodes with larger cathode catalyst particles. To delineate the impact of particle size and alloy effects, these results are compared with prior work from our research group on size effects of pure platinum catalysts. The impact of PEMFC operating conditions, including upper potential, relative humidity, and temperature on the alloy catalyst decay trends, along with the EMPA analysis of the decayed MEAs, are reported.

  15. Luminescence studies of CdS spherical particles via hydrothermal synthesis

    Science.gov (United States)

    Xu, Guo Qin; Liu, Bing; Xu, Shi Jie; Chew, Chwee Har; Chua, Soo Jin; Gana, Leong Ming

    2000-06-01

    The spherical particles of CdS consisting of nanoparticles (∼100 nm) were synthesized by a hydrothermal process. The particle formation and growth depend on the rate of sulfide-ion generation and diffusion-controlled aggregation of nanoparticles. As demonstrated in the profiles of powder X-ray diffraction, the crystalline phases are governed by the reaction temperature. Photoluminescence studies on CdS particles show two emission bands at the room temperature. The red emission at 680 nm is due to sulfur vacancies, and a new infrared red (IR) emission at 760 nm is attributed to self-activated centers. A red shift of IR band with the decrease of temperature was explained with a configurational coordinate model. The different saturation limits for the red and IR bands are discussed in terms of the formation of donor-acceptor pairs and exciton in CdS particles.

  16. Investigation of a Pulsed 1550 nm Fiber Laser System (Briefing Charts)

    Science.gov (United States)

    2016-02-14

    Pump dump and splice Pump dump and splice MFA 976 nm 15 W TFB TFB Pump dump and splice Waveform shaping Delay Power meter...filter 976 nm 7.6 W TFB WDM Pump dump and splice Pump dump and splice MFA 976 nm 15 W TFB TFB Pump dump and splice Waveform shaping...Multimode fiber to OSA or photodiode EOM EOM ASE filter ASE filter 976 nm 7.6 W TFB

  17. Combination of Q-switched and quasi long-pulsed 1064-nm Nd:YAG laser, non-ablative 1450-nm diode laser, and ablative 10 600-nm carbon dioxide fractional laser for enlarged pores.

    Science.gov (United States)

    Cho, Sung Bin; Noh, Seongmin; Lee, Sang Ju; Kang, Jin Moon; Kim, Young Koo; Lee, Ju Hee

    2010-07-01

    Currently, there is no gold standard for the treatment of enlarged facial pores. In this report, we describe a patient with enlarged nasal pores which were treated with a combination of a non-ablative 1450-nm diode laser, a Q-switched and quasi long-pulsed 1064-nm Nd:YAG laser, and an ablative 10 600-nm carbon dioxide fractional laser system. Four months after the final treatment, the condition of the patient's pores had markedly improved, and the patient was satisfied with the results.

  18. A comparative study with a 755 nm picosecond Alexandrite laser with a diffractive lens array and a 532 nm/1064 nm Nd:YAG with a holographic optic.

    Science.gov (United States)

    Tanghetti Md, Emil; Jennings, John

    2018-01-01

    This study was performed to better understand the cutaneous effects of using a fractional picosecond laser at 755 nm with a diffractive lens array and a picosecond Nd:YAG laser at 532 mn and 1064 nm with a holographic optic. We characterized the injuries created by these devices on skin clinically and histologically over 24 hours. With this information we modeled the effects of these devices on a cutaneous target. Eight patients, representing Fitzpatrick skin types I-VI, were treated on their backs with a picosecond Alexandrite laser with a diffractive lens array, as well as a picosecond Nd:YAG laser at 532 nm and 1064 nm with a holographic optic. Photographs were taken 15 minutes and 24 hours after treatments. Punch biopsies were obtained at 24 hours and examined histologically. Treatment with the picosecond Nd:YAG laser at both 532 nm and 1064 nm with the holographic optic revealed erythema and small scatted areas of petechial hemorrhage areas immediately and in many cases at 24 hours after treatment. The 755 nm picosecond Alexandrite laser with diffractive lens array produced erythema immediately after treatment, which largely dissipated 24 hours later. Histologies revealed intra-epidermal vacuoles with all three wavelengths. Fractional picosecond Nd:YAG laser at 532 nm and 1064 nm with the holographic optic showed focal areas of dermal and intra-epidermal hemorrhage with areas of vascular damage in some patients. This study demonstrates that both fractional picosecond devices produce vacuoles in the skin, which are most likely due to areas of laser induced optical breakdown (LIOB). In the patients (skin type II-IV) we observed scatter areas of hemorrhage in the skin, due to vascular damage with the 532 nm and 1064 nm, but not with 755 nm wavelengths. Lasers Surg. Med. 50:37-44, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Treatment of inflammatory facial acne vulgaris with combination 595-nm pulsed-dye laser with dynamic-cooling-device and 1,450-nm diode laser.

    Science.gov (United States)

    Glaich, Adrienne S; Friedman, Paul M; Jih, Ming H; Goldberg, Leonard H

    2006-03-01

    The 585-nm pulsed-dye laser and the 1,450-nm diode laser have been found effective for the treatment of mild-to-moderate inflammatory facial acne. This study was designed to evaluate the efficacy and safety of the combined treatment with the 595-nm pulsed-dye laser and the 1,450-nm diode laser for inflammatory facial acne. Fifteen patients with inflammatory facial acne were treated with a combination of the 595-nm pulsed-dye laser and the 1,450-nm diode laser. Patients' subjective response to treatment was evaluated regarding improvement in acne, acne scarring, oiliness, and redness of the skin. All patients had reductions in acne lesion counts. Mean lesion counts decreased 52% (P < 0.01), 63% (P < 0.01), and 84% (P < 0.01) after one, two, and three treatments, respectively. Patients described moderate-to-marked improvement in acne, acne scarring, and post-inflammatory erythema. Adverse effects were limited to mild, transient erythema. The combination of the 595-nm pulsed-dye laser and the 1,450-nm diode laser is safe and effective for the treatment of inflammatory facial acne, acne scarring, and post-inflammatory erythema. 2005 Wiley-Liss, Inc.

  20. Artificial neural network based particle size prediction of polymeric nanoparticles.

    Science.gov (United States)

    Youshia, John; Ali, Mohamed Ehab; Lamprecht, Alf

    2017-10-01

    Particle size of nanoparticles and the respective polydispersity are key factors influencing their biopharmaceutical behavior in a large variety of therapeutic applications. Predicting these attributes would skip many preliminary studies usually required to optimize formulations. The aim was to build a mathematical model capable of predicting the particle size of polymeric nanoparticles produced by a pharmaceutical polymer of choice. Polymer properties controlling the particle size were identified as molecular weight, hydrophobicity and surface activity, and were quantified by measuring polymer viscosity, contact angle and interfacial tension, respectively. A model was built using artificial neural network including these properties as input with particle size and polydispersity index as output. The established model successfully predicted particle size of nanoparticles covering a range of 70-400nm prepared from other polymers. The percentage bias for particle prediction was 2%, 4% and 6%, for the training, validation and testing data, respectively. Polymer surface activity was found to have the highest impact on the particle size followed by viscosity and finally hydrophobicity. Results of this study successfully highlighted polymer properties affecting particle size and confirmed the usefulness of artificial neural networks in predicting the particle size and polydispersity of polymeric nanoparticles. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Increase of the photosensitivity of undoped poly(methylmethacrylate) under UV radiation at 325 nm

    DEFF Research Database (Denmark)

    Sáez-Rodríguez, D.; Nielsen, Kristian; Bang, Ole

    2014-01-01

    in undoped PMMA mPOFs with a hexagonal structure of three rings in the inner cladding. Two sets of FBGs were inscribed at two different resonant wavelengths (827 nm and 1562 nm) at different strains using an UV He-Cd laser at 325 nm focused by a lens and scanned over the fibre. We observed an increase...

  2. Particle size determination

    International Nuclear Information System (INIS)

    Burr, K.J.

    1979-01-01

    A specification is given for an apparatus to provide a completely automatic testing cycle to determine the proportion of particles of less than a predetermined size in one of a number of fluid suspensions. Monitoring of the particle concentration during part of the process can be carried out by an x-ray source and detector. (U.K.)

  3. Elementary particle theory

    CERN Document Server

    Stefanovich, Eugene

    2018-01-01

    This book introduces notation, terminology, and basic ideas of relativistic quantum theories. The discussion proceeds systematically from the principle of relativity and postulates of quantum logics to the construction of Poincaré invariant few-particle models of interaction and scattering. It is the first of three volumes formulating a consistent relativistic quantum theory of interacting charged particles.

  4. History of Particle Physics

    Science.gov (United States)

    back to history page Back Particle Physics Timeline For over two thousand years people have thought the Standard Model. We invite you to explore this history of particle physics with a focus on the : Quantum Theory 1964 - Present: The Modern View (the Standard Model) back to history page Back Sections of

  5. Light particles in turbulence

    NARCIS (Netherlands)

    Nagendra Prakash, Vivek

    2013-01-01

    This thesis deals with the broad topic of particles in turbulence, which has applications in a diverse number of fields. A vast majority of fluid flows found in nature and in the industry are turbulent and contain dispersed elements. In this thesis, I have focused on light particles (air bubbles in

  6. Particle physics instrumentation

    International Nuclear Information System (INIS)

    Riegler, W.

    2011-01-01

    This report summarizes a series of three lectures aimed at giving an overview of basic particle detection principles, the interaction of particles with matter, the application of these principles in modern detector systems, as well techniques to read out detector signals in high-rate experiments. (author)

  7. Particles, contacts, bulk behavior

    NARCIS (Netherlands)

    Luding, Stefan; Tomas, J.

    2014-01-01

    Granular matter consists of discrete “particles”. These can be separate sand-grains, agglomerates (made of many primary particles), or solid materials like rock, composites, or metal-alloys—all with particulate inhomogeneous, possibly anisotropic micro-structure. Particles can be as small as

  8. Particle Astrophysics of Neutrinos

    Indian Academy of Sciences (India)

    Amol Dighe

    Energy spectra of neutrino sources. ASPERA. Page 4. Some unique features of neutrinos. The second most abundant particles in the universe. Cosmic microwave background photons: 400 / cm3. Cosmic background neutrinos: 330 / cm3. The lightest massive particles. A million times lighter than the electron. No direct mass ...

  9. Astro-particle-physics

    International Nuclear Information System (INIS)

    Salam, A.

    1985-09-01

    Opening remarks at the Fourth Marcel Grossman Meeting, 17-21 June 1985, in Rome, Italy, are reported. The meeting was concerned with the symbiosis of cosmology and particle physics. Numerous connections between work in particle physics and cosmology, in both experimental and theoretical areas, are pointed out

  10. When is a particle

    International Nuclear Information System (INIS)

    Drell, S.D.

    1978-01-01

    The concept of elementary constituents or ultimate building blocks of nature in recent years is reviewed. The quark hypothesis, neutrinos, color, hard collisions, psi and other recent resonances, flavor, quantum chromodynamics, the tau particle, and particle structure are among the ideas considered. 22 references

  11. Concepts of particle physics

    International Nuclear Information System (INIS)

    Gottfried, K.; Weisskopf, V.F.

    1984-01-01

    This volume elucidates basic and well-established concepts of particle physics for the autodidact who is curious about recent developments in fundamental physics. Elementary quantum mechanics is a background must. Contents, abridged: The evolution of the particle concept before the advent of quantum mechanics. Nonrelativistic quantum mechanics and atomic physics. Relativistic quantum theory. Nuclear phenomena. Subnuclear phenomena. Index

  12. RESEARCH IN PARTICLE PHYSICS

    Energy Technology Data Exchange (ETDEWEB)

    Kearns, Edward [Boston Universiy

    2013-07-12

    This is the final report for the Department of Energy Grant to Principal Investigators in Experimental and Theoretical Particle Physics at Boston University. The research performed was in the Energy Frontier at the LHC, the Intensity Frontier at Super-Kamiokande and T2K, the Cosmic Frontier and detector R&D in dark matter detector development, and in particle theory.

  13. Optics of charged particles

    International Nuclear Information System (INIS)

    Wollnik, H.

    1987-01-01

    Suitable for both the specialist and non-specialist, this book develops all statements from first principles. Key chapters of the book focus upon how to design particle-optical systems, the systematics of image abberations, the effects of fringing fields, systematics of beams, and solutions for particle-optical systems. An undergraduate background in physics and mathematics is required for this work

  14. Introduction to particle physics

    International Nuclear Information System (INIS)

    Zitoun, R.

    2000-01-01

    This book proposes an introduction to particle physics that requires only a high-school level mathematical knowledge. Elementary particles (leptons, quarks, bosons) are presented according to a modern view taking into account of their symmetries and interactions. The author shows how physicists have elaborated the standard model and what are its implications in cosmology. (J.S.)

  15. Microchip Coulter particle counter

    DEFF Research Database (Denmark)

    Larsen, Ulrik Darling; Blankenstein, Gert; Branebjerg, J.

    1997-01-01

    This paper presents a micro device employing the Coulter principle for counting and sizing of living cells and particles in liquid suspension. The microchip Coulter particle counter (μCPC) has been employed in a planar silicon structure covered with glass, which enables detailed observation during...

  16. Interactive Terascale Particle Visualization

    Science.gov (United States)

    Ellsworth, David; Green, Bryan; Moran, Patrick

    2004-01-01

    This paper describes the methods used to produce an interactive visualization of a 2 TB computational fluid dynamics (CFD) data set using particle tracing (streaklines). We use the method introduced by Bruckschen et al. [2001] that pre-computes a large number of particles, stores them on disk using a space-filling curve ordering that minimizes seeks, and then retrieves and displays the particles according to the user's command. We describe how the particle computation can be performed using a PC cluster, how the algorithm can be adapted to work with a multi-block curvilinear mesh, and how the out-of-core visualization can be scaled to 296 billion particles while still achieving interactive performance on PG hardware. Compared to the earlier work, our data set size and total number of particles are an order of magnitude larger. We also describe a new compression technique that allows the lossless compression of the particles by 41% and speeds the particle retrieval by about 30%.

  17. Teaching particle physics

    CERN Document Server

    Hanley, P

    2000-01-01

    Particle physics attracts many students who hear of news from CERN or elsewhere in the media. This article examines which current A-level syllabuses include which bits of particle physics and surveys the many different types of resource available to teachers and students. (0 refs).

  18. Particles, imaging and nuclei

    International Nuclear Information System (INIS)

    Harris, J.

    1986-01-01

    The book on particles, imaging and nuclei is one of the Background Readers for the Revised Nuffield Advanced Physics course. The contents contain five educational articles, which extend concepts covered in the course and examine recent developments in physics. Four of the articles on:- particles and the forces of nature, radioisotopes, lasers probe the atomic nucleus, and nuclear history, are indexed separately. (UK)

  19. 16.7 W 885 nm diode-side-pumped actively Q -switched Nd:YAG/YVO4 intracavity Raman laser at 1176 nm

    International Nuclear Information System (INIS)

    Jiang, Pengbo; Zhang, Guizhong; Liu, Jian; Ding, Xin; Sheng, Quan; Sun, Bing; Shi, Rui; Wu, Liang; Yao, Jianquan; Yu, Xuanyi; Wang, Rui

    2017-01-01

    We proposed and experimentally demonstrated the generation of high-power 1176 nm Stokes wave by frequency shifting of a 885 nm diode-side-pumped Nd:YAG laser using a YVO 4 crystal in a Z -shaped cavity configuration. Employing the 885 nm diode-side-pumped scheme and the Z -shaped cavity, for the first time to our knowledge, we realized the thermal management effectively, achieving excellent 1176 nm Stokes wave consequently. With an incident pump power of ∼190.0 W, a maximum average output power of 16.7 W was obtained at the pulse repetition frequency of 10 kHz. The pulse duration and spectrum linewidth of the Stokes wave at the maximum output power were 20.3 ns and ∼0.08 nm, respectively. (paper)

  20. Enhancement of 800 nm upconversion emission in a thulium doped tellurite microstructured fiber pumped by a 1560 nm femtosecond fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Zhixu; Zheng, Kezhi [State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Yangtze Optical Fiber and Cable Joint Stock Limited Company, Wuhan 430073 (China); State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Yao, Chuanfei; Wang, Shunbin; Qin, Guanshi, E-mail: qings@jlu.edu.cn; Qin, Weiping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Xiong, Liangming; Luo, Jie; Lv, Dajuan [State Key Laboratory of Optical Fiber and Cable Manufacture Technology, Yangtze Optical Fiber and Cable Joint Stock Limited Company, Wuhan 430073 (China); Ohishi, Yasutake [Research Center for Advanced Photon Technology, Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya 468–8511 (Japan)

    2016-04-28

    We report enhanced upconversion (UC) fluorescence in Tm{sup 3+} doped tellurite microstructured fibers (TDTMFs) fabricated by using a rod-in-tube method. Under the pumping of a 1560 nm femtosecond fiber laser, ultrabroadband supercontinuum light expanding from ∼1050 to ∼2700 nm was generated in a 4 cm long TDTMF. Simultaneously, intense 800 nm UC emission from the {sup 3}H{sub 4} → {sup 3}H{sub 6} transition of Tm{sup 3+} was observed in the same TDTMF. Compared to that pumped by a 1560 nm continuous wave fiber laser, the UC emission intensity was enhanced by ∼4.1 times. The enhancement was due to the spectral broadening in the TDTMF under the pumping of the 1560 nm femtosecond fiber laser.